阅读说明：本技术 挖土机 (Excavator ) 是由 三崎阳二 白谷龙二 于 2020-03-19 设计创作，主要内容包括：本发明的实施方式所涉及的挖土机(100)具有：左主泵(14L)；斗杆缸(8)；回转液压马达(2A)；换向阀(173),与回转液压马达(2A)对应；换向阀(176L),与斗杆缸(8)对应；左中间旁通管路(40L),连接左主泵(14L)与换向阀(173)；控制阀(177),设置在连接左中间旁通管路(40L)与换向阀(176L)的左并联管路(42L)上；及控制器(30),根据与作业内容相关的信息来控制控制阀(177)的开口面积。(A shovel (100) according to an embodiment of the present invention includes: a left main pump (14L); a bucket rod cylinder (8); a rotary hydraulic motor (2A); a selector valve (173) corresponding to the rotary hydraulic motor (2A); a direction change valve (176L) corresponding to the arm cylinder (8); a left intermediate bypass line (40L) connecting the left main pump (14L) and the selector valve (173); a control valve (177) disposed on a left parallel line (42L) connecting the left intermediate bypass line (40L) and the diverter valve (176L); and a controller (30) for controlling the opening area of the control valve (177) according to information related to the operation content.)

1. An excavator, having:

a lower traveling body;

an upper revolving body which is rotatably mounted on the lower traveling body;

a1 st hydraulic pump provided on the upper slewing body;

an attachment mounted on the upper slewing body;

1 st actuator;

a2 nd actuator;

the 1 st reversing valve corresponds to the 1 st actuator;

a2 nd direction changing valve corresponding to the 2 nd actuator;

the 1 st pipeline is used for connecting the 1 st hydraulic pump and the 1 st reversing valve;

the 2 nd pipeline is connected with the 1 st pipeline and the 2 nd reversing valve;

the control valve is arranged on the 2 nd pipeline; and

and a control device for controlling the opening area of the control valve according to information related to the work content.

2. The shovel of claim 1,

the 1 st actuator is a slewing hydraulic motor provided in the upper slewing body.

3. The shovel of claim 1,

the 2 nd actuator is an actuator that actuates the attachment.

4. The shovel of claim 1,

the 2 nd pipeline connects the 1 st pipeline located at the upstream side of the 1 st direction changing valve with the 2 nd direction changing valve.

5. The shovel of claim 1,

the control device determines the work content based on the discharge pressure of the 1 st hydraulic pump.

6. The shovel of claim 1,

in the case of performing a combined operation including a swing operation and an operation of the attachment, and in the case where a load is equal to or greater than a predetermined threshold value, the control device sets the opening area of the control valve to a1 st set value that is smaller than a predetermined reference value.

7. The shovel of claim 6,

in the case of performing a combined operation including a swing operation and an operation of the attachment, and in the case where a load is less than a predetermined threshold value, the control device sets the opening area of the control valve to a2 nd set value that is less than the reference value and greater than the 1 st set value.

8. The shovel of claim 6,

the reference value is an opening area of the control valve when the swing operation is not performed.

9. The shovel of claim 1,

the 2 nd actuator is an arm cylinder.

10. The shovel of claim 1 having:

a pilot pump; and

an electromagnetic valve is arranged on the base plate,

the solenoid valve is disposed on a pipe line connecting the control valve and the pilot pump.

11. The shovel of claim 1 having:

a2 nd hydraulic pump different from the 1 st hydraulic pump;

a3 rd direction changing valve corresponding to the 2 nd actuator and different from the 2 nd direction changing valve; and

a conduit connecting the 2 nd actuator with the 3 rd directional valve,

the pipe line includes a confluence point at which the hydraulic fluid discharged from the 1 st hydraulic pump and the hydraulic fluid discharged from the 2 nd hydraulic pump merge together,

the control valve is disposed upstream of the confluence point.

12. The shovel of claim 1,

the control device determines the content of the work based on at least one of a posture detection device that detects the posture of the attachment, an image captured by a camera, and a value output by a cylinder pressure sensor.

Technical Field

The present invention relates to an excavator.

Background

Conventionally, there is known a shovel that increases a flow rate of hydraulic oil flowing into a swing hydraulic motor by reducing the flow rate of hydraulic oil flowing into an arm cylinder when performing excavation based on a combined operation including a swing operation and an arm closing operation (see patent document 1).

This excavation is typically performed by closing an arm while pressing a side surface of the bucket against an excavation target (hereinafter, also referred to as "swing-press excavation").

The excavator can prevent the pressing force of the rotary hydraulic motor from being insufficient by preferentially supplying the hydraulic oil to the rotary hydraulic motor. Therefore, the operator of the excavator can smoothly perform excavation as described above.

Prior art documents

Patent document

Patent document 1: japanese laid-open patent publication No. 9-279637

Disclosure of Invention

Technical problem to be solved by the invention

However, in the above-described excavator, even when a combined operation including a turning operation and an arm closing operation is performed when the side surface of the bucket is not in contact with the excavation target, there is a possibility that the flow rate of the hydraulic oil flowing into the arm cylinder is reduced and the operation of the arm is unstable.

Therefore, it is preferable to stabilize the operation of the shovel at the time of performing the combined operation including the turning operation.

Means for solving the technical problem

An excavator according to an embodiment of the present invention includes: a lower traveling body; an upper revolving body which is rotatably mounted on the lower traveling body; a1 st hydraulic pump provided on the upper slewing body; an attachment mounted on the upper slewing body; 1 st actuator; a2 nd actuator; the 1 st reversing valve corresponds to the 1 st actuator; a2 nd direction changing valve corresponding to the 2 nd actuator; the 1 st pipeline is used for connecting the 1 st hydraulic pump and the 1 st reversing valve; the 2 nd pipeline is connected with the 1 st pipeline and the 2 nd reversing valve; the control valve is arranged on the 2 nd pipeline; and a control device for controlling the opening area of the control valve according to information related to the operation content.

Effects of the invention

With the above configuration, the operation of the shovel can be stabilized when performing a combined operation including a turning operation.

Drawings

Fig. 1 is a side view of a shovel according to an embodiment of the present invention.

Fig. 2 is a top view of the excavator of fig. 1.

Fig. 3 is a diagram showing a configuration example of a hydraulic system mounted on the shovel of fig. 1.

Fig. 4 is a diagram showing a relationship between the right-turn pilot pressure and the opening area of the control valve.

Fig. 5 is a flowchart of an example of the adjustment processing.

Fig. 6 is a diagram showing another configuration example of a hydraulic system mounted on the shovel of fig. 1.

Fig. 7 is a diagram showing a configuration example of an electric operation system.

Fig. 8 is a diagram showing a relationship between the right swing operation signal and the opening area of the control valve.

Fig. 9 is a diagram showing still another configuration example of a hydraulic system mounted on the shovel of fig. 1.

Fig. 10 is a diagram showing another configuration example of the shovel according to the embodiment of the present invention.

Detailed Description

First, a shovel 100 as an excavator according to an embodiment of the present invention will be described with reference to fig. 1 and 2. Fig. 1 is a side view of the shovel 100, and fig. 2 is a plan view of the shovel 100.

In the present embodiment, the lower traveling body 1 of the shovel 100 includes a crawler belt 1C. The crawler belt 1C is driven by a traveling hydraulic motor 2M as a traveling actuator mounted on the lower traveling body 1. Specifically, crawler belt 1C includes left crawler belt 1CL and right crawler belt 1 CR. The left crawler belt 1CL is driven by a left traveling hydraulic motor 2ML, and the right crawler belt 1CR is driven by a right traveling hydraulic motor 2 MR.

An upper turning body 3 is rotatably mounted on the lower traveling body 1 via a turning mechanism 2. The turning mechanism 2 is driven by a turning hydraulic motor 2A as a turning actuator mounted on the upper turning body 3.

A boom 4 is attached to the upper slewing body 3. An arm 5 is attached to a front end of the boom 4, and a bucket 6 as a terminal attachment is attached to a front end of the arm 5. The boom 4, the arm 5, and the bucket 6 constitute an excavation attachment AT as an example of an attachment. Boom 4 is driven by boom cylinder 7, arm 5 is driven by arm cylinder 8, and bucket 6 is driven by bucket cylinder 9. The boom cylinder 7, the arm cylinder 8, and the bucket cylinder 9 constitute an attachment actuator.

The boom 4 is supported to be vertically rotatable with respect to the upper slewing body 3. Further, a boom angle sensor S1 is attached to the boom 4. The boom angle sensor S1 can detect a boom angle θ 1 which is a turning angle of the boom 4. The boom angle θ 1 is, for example, a rising angle from a state in which the boom 4 is lowered to the lowest position. Therefore, the boom angle θ 1 becomes maximum when the boom 4 is lifted to the highest position.

The arm 5 is supported rotatably with respect to the boom 4. Further, the arm 5 is attached with an arm angle sensor S2. The arm angle sensor S2 can detect an arm angle θ 2 that is a rotation angle of the arm 5. The arm angle θ 2 is, for example, an opening angle from a state where the arm 5 is closed to the maximum. Therefore, the arm angle θ 2 is maximized when the arm 5 is maximally opened.

The bucket 6 is supported rotatably with respect to the arm 5. Further, a bucket angle sensor S3 is attached to the bucket 6. The bucket angle sensor S3 can detect a bucket angle θ 3 as a rotation angle of the bucket 6. The bucket angle θ 3 is, for example, an opening angle from a state where the bucket 6 is maximally closed. Therefore, the bucket angle θ 3 is maximized when the bucket 6 is maximally opened.

In the embodiment of fig. 1, the boom angle sensor S1, the arm angle sensor S2, and the bucket angle sensor S3 are each configured by a combination of an acceleration sensor and a gyro sensor. However, the acceleration sensor may be constituted only by the acceleration sensor. The boom angle sensor S1 may be a stroke sensor attached to the boom cylinder 7, or may be a rotary encoder, a potentiometer, an inertial measurement unit, or the like. The same applies to the stick angle sensor S2 and the bucket angle sensor S3.

The upper slewing body 3 is provided with a cab 10 as a cab, and is mounted with a power source such as an engine 11. The upper slewing body 3 is provided with a space recognition device 70, a direction detection device 71, a positioning device 73, a body inclination sensor S4, a slewing angular velocity sensor S5, and the like. The cabin 10 is provided therein with an operation device 26, a controller 30, an information input device 72, a display device D1, a voice output device D2, and the like. In the present description, for convenience, the side of the upper revolving structure 3 to which the excavation attachment AT is attached is referred to as the front side, and the side to which the counterweight is attached is referred to as the rear side.

The space recognition device 70 is configured to be able to recognize objects existing in a three-dimensional space around the shovel 100. The space recognition device 70 is configured to calculate a distance from the space recognition device 70 or the shovel 100 to the recognized object. The space recognition device 70 is, for example, an ultrasonic sensor, a millimeter wave radar, a monocular camera, a stereo camera, a LIDAR, a range image sensor, an infrared sensor, or the like. In the example shown in fig. 1 and 2, the space recognition device 70 includes a front sensor 70F attached to the front end of the upper surface of the cab 10, a rear sensor 70B attached to the rear end of the upper surface of the upper revolving structure 3, a left sensor 70L attached to the left end of the upper surface of the upper revolving structure 3, and a right sensor 70R attached to the right end of the upper surface of the upper revolving structure 3. An upper sensor for recognizing an object existing in a space above the upper slewing body 3 may be attached to the shovel 100.

The direction detection device 71 is configured to detect information relating to the relative relationship between the direction of the upper revolving unit 3 and the direction of the lower traveling unit 1. Direction detecting device 71 may be constituted by a combination of a geomagnetic sensor attached to lower traveling structure 1 and a geomagnetic sensor attached to upper revolving structure 3, for example. Alternatively, the direction detection device 71 may be constituted by a combination of a GNSS receiver mounted on the lower traveling structure 1 and a GNSS receiver mounted on the upper revolving structure 3. The orientation detection device 71 may be a rotary encoder, a rotary position sensor, or the like. In the configuration in which the upper slewing body 3 is rotationally driven by the slewing motor generator, the direction detector 71 may be constituted by a resolver. The orientation detection device 71 may be attached to, for example, a center joint portion provided in association with the turning mechanism 2 that realizes relative rotation between the lower traveling body 1 and the upper turning body 3.

The orientation detection device 71 may be constituted by a camera attached to the upper revolving unit 3. At this time, the orientation detection device 71 performs known image processing on an image (input image) captured by a camera attached to the upper revolving structure 3 to detect an image of the lower traveling structure 1 included in the input image. Then, the orientation detection device 71 detects the image of the lower traveling body 1 by using a known image recognition technique, and determines the longitudinal direction of the lower traveling body 1. Then, an angle formed between the front-rear axis direction of the upper revolving structure 3 and the longitudinal direction of the lower traveling structure 1 is derived. The front-rear axis direction of the upper revolving structure 3 is derived from the mounting position of the camera. Since the crawler belt 1C protrudes from the upper revolving structure 3, the orientation detection device 71 can determine the longitudinal direction of the lower traveling structure 1 by detecting an image of the crawler belt 1C. At this time, the orientation detection device 71 may be integrated with the controller 30.

The information input device 72 is configured to allow an operator of the excavator to input information to the controller 30. In the present embodiment, the information input device 72 is a switch panel provided in the vicinity of the display unit of the display device D1. However, the information input device 72 may be a touch panel disposed on the display portion of the display device D1, or may be a voice input device such as a microphone disposed in the cabin 10. The information input device 72 may be a communication device. At this time, the operator can input information to the controller 30 via a communication terminal such as a smartphone.

The positioning device 73 is configured to measure a current position. In the present embodiment, positioning device 73 is a GNSS receiver that detects the position of upper revolving unit 3 and outputs the detected value to controller 30. The positioning device 73 may also be a GNSS compass. At this time, positioning device 73 can detect the position and orientation of upper revolving unit 3.

The body inclination sensor S4 is configured to detect the inclination of the upper slewing body 3 with respect to a predetermined plane. In the present embodiment, the body inclination sensor S4 is an acceleration sensor that detects the inclination of the upper slewing body 3 about the front-rear axis and the inclination about the left-right axis with respect to the horizontal plane. The front-rear axis and the left-right axis of the upper revolving structure 3 are orthogonal to each other and pass through a shovel center point, which is one point on the revolving shaft of the shovel 100, for example.

The turning angular velocity sensor S5 is configured to detect the turning angular velocity of the upper revolving structure 3. In the present embodiment, the rotation angular velocity sensor S5 is a gyro sensor. The rotational angular velocity sensor S5 may be a resolver, a rotary encoder, or the like. The revolution angular velocity sensor S5 may also detect a revolution speed. The slew velocity may be calculated from the slew angular velocity.

Hereinafter, at least one of the boom angle sensor S1, the arm angle sensor S2, the bucket angle sensor S3, the body inclination sensor S4, and the turning angular velocity sensor S5 is also referred to as a posture detection device. The posture of the excavation attachment AT is detected from the outputs of the boom angle sensor S1, the arm angle sensor S2, and the bucket angle sensor S3, for example.

The display device D1 is a device that displays information. In the present embodiment, the display device D1 is a liquid crystal display provided in the cabin 10. However, the display device D1 may be a display of a communication terminal such as a smartphone.

The voice output device D2 is a device that outputs voice. The voice output device D2 includes at least one of a device for outputting voice to an operator in the cab 10 and a device for outputting voice to a worker outside the cab 10. The voice output device D2 may be a speaker attached to the communication terminal.

The operation device 26 is a device used by an operator to operate the actuator. The operating device 26 is provided in the cab 10 in such a manner as to be accessible to an operator sitting in the driver's seat.

The controller 30 is a control device for controlling the shovel 100. In the present embodiment, the controller 30 is constituted by a computer including a CPU, a RAM, an NVRAM, a ROM, and the like. The controller 30 reads a program corresponding to the functional elements such as the information acquisition unit 30a and the control unit 30b from the ROM, loads the program into the RAM, and causes the CPU to execute processing corresponding to each functional element. In this manner, each functional element is realized by software. However, at least one of the functional elements may be implemented by hardware or firmware. The functional elements are separated for convenience of explanation, and are a part of the controller 30, and it is not necessary to physically separate the functional elements.

Next, a configuration example of a hydraulic system mounted on the shovel 100 will be described with reference to fig. 3. Fig. 3 is a diagram showing a configuration example of a hydraulic system mounted on the shovel 100. The mechanical power transmission system, the working oil line, the pilot line, and the electrical control system are shown in fig. 3 by double lines, solid lines, broken lines, and dotted lines, respectively.

The hydraulic system of the shovel 100 mainly includes an engine 11, a regulator 13, a main pump 14, a pilot pump 15, a control valve unit 17, an operation device 26, a discharge pressure sensor 28, an operation pressure sensor 29, a controller 30, a solenoid valve 50, and the like.

In fig. 3, the hydraulic system is configured to be able to circulate hydraulic oil from the main pump 14 driven by the engine 11 to the hydraulic oil tank via the intermediate bypass line 40 or the parallel line 42.

The engine 11 is a drive source of the shovel 100. In the present embodiment, the engine 11 is, for example, a diesel engine that operates to maintain a predetermined number of revolutions. An output shaft of the engine 11 is coupled to respective input shafts of the main pump 14 and the pilot pump 15.

The main pump 14 is configured to be able to supply hydraulic oil to the control valve unit 17 via a hydraulic oil line. In the present embodiment, the main pump 14 is a swash plate type variable displacement hydraulic pump.

The regulator 13 is configured to be able to control the discharge rate of the main pump 14. In the present embodiment, the regulator 13 controls the discharge rate of the main pump 14 by adjusting the swash plate tilt angle of the main pump 14 in accordance with a control command from the controller 30.

The pilot pump 15 is configured to be able to supply hydraulic oil to a hydraulic control apparatus including an operation device 26 via a pilot line. In the present embodiment, the pilot pump 15 is a fixed displacement hydraulic pump. However, the pilot pump 15 may be omitted. In this case, the function of the pilot pump 15 can be realized by the main pump 14. That is, in addition to the function of supplying the hydraulic oil to the control valve unit 17, the main pump 14 may also have a function of supplying the hydraulic oil to the operation device 26 and the like after reducing the pressure of the hydraulic oil by an orifice and the like.

The control valve unit 17 is a hydraulic control device that controls a hydraulic system in the shovel 100. In the present embodiment, the control valve unit 17 includes the selector valves 171 to 176 and the control valve 177. The direction valve 175 includes a direction valve 175L and a direction valve 175R, and the direction valve 176 includes a direction valve 176L and a direction valve 176R. The control valve unit 17 is configured to be able to selectively supply the hydraulic oil discharged from the main pump 14 to one or more hydraulic actuators via the selector valves 171 to 176. The selector valves 171 to 176 control, for example, the flow rate of hydraulic oil flowing from the main pump 14 to the hydraulic actuators and the flow rate of hydraulic oil flowing from the hydraulic actuators to the hydraulic oil tank. The hydraulic actuators include a boom cylinder 7, an arm cylinder 8, a bucket cylinder 9, a left traveling hydraulic motor 2ML, a right traveling hydraulic motor 2MR, and a swing hydraulic motor 2A.

The operation device 26 is a device used by an operator to operate the actuator. The operation device 26 includes, for example, an operation lever and an operation pedal. The actuator includes at least one of a hydraulic actuator and an electric actuator. In the present embodiment, the operation device 26 is configured to be able to supply the hydraulic oil discharged from the pilot pump 15 to the pilot port of the corresponding selector valve in the control valve unit 17 via the pilot line. The pressure (pilot pressure) of the hydraulic oil supplied to each pilot port is a pressure corresponding to the operation direction and the operation amount of the operation device 26 corresponding to each hydraulic actuator. However, the operating device 26 may also be of the electromagnetic pilot type instead of the hydraulic pilot type as described above. Alternatively, the directional valve in the control valve unit 17 may be an electromagnetic solenoid type spool valve. Specifically, instead of the hydraulic operation system including the hydraulic pilot circuit, an electric operation system including an electric operation lever including an electric pilot circuit may be employed. At this time, the lever operation amount of the electric operation lever is input to the controller 30 as an electric signal. Further, an electromagnetic valve is disposed between the pilot pump 15 and the pilot port of each control valve. The solenoid valve is configured to operate in response to an electric signal from the controller 30. According to this configuration, when a manual operation using an electric operation lever is performed, the controller 30 controls the solenoid valve based on an electric signal corresponding to the lever operation amount to increase or decrease the pilot pressure, thereby moving each control valve in the control valve unit 17. In addition, each control valve may be constituted by an electromagnetic spool valve. At this time, the solenoid spool operates in response to an electric signal from the controller 30 corresponding to the lever operation amount of the electric operation lever.

The discharge pressure sensor 28 may be configured to detect the discharge pressure of the main pump 14. In the present embodiment, the discharge pressure sensor 28 outputs the detected value to the controller 30.

The operation pressure sensor 29 can be configured to detect the content of an operation performed by the operator on the operation device 26. In the present embodiment, the operation pressure sensor 29 detects the operation direction and the operation amount of the operation device 26 corresponding to each actuator as a pressure (operation pressure), and outputs the detected values to the controller 30. The operation content of the operation device 26 may be detected by a sensor other than the operation pressure sensor.

Main pump 14 includes a left main pump 14L and a right main pump 14R. The left main pump 14L circulates hydraulic oil to the hydraulic oil tank through the left intermediate bypass line 40L or the left parallel line 42L, and the right main pump 14R circulates hydraulic oil to the hydraulic oil tank through the right intermediate bypass line 40R or the right parallel line 42R.

The left intermediate bypass line 40L is a working oil line passing through the direction change valves 171, 173, 175L, and 176L arranged in the control valve unit 17. The right intermediate bypass line 40R is a working oil line passing through the direction change valves 172, 174, 175R, and 176R arranged in the control valve unit 17.

The selector valve 171 is a spool valve that switches the flow of the hydraulic oil in order to supply the hydraulic oil discharged from the left main pump 14L to the left travel hydraulic motor 2ML and discharge the hydraulic oil discharged from the left travel hydraulic motor 2ML to a hydraulic oil tank.

The selector valve 172 is a spool valve that switches the flow of the hydraulic oil in order to supply the hydraulic oil discharged from the right main pump 14R to the right travel hydraulic motor 2MR and discharge the hydraulic oil discharged from the right travel hydraulic motor 2MR to a hydraulic oil tank.

The selector valve 173 is a spool valve that switches the flow of the hydraulic oil in order to supply the hydraulic oil discharged from the left main pump 14L to the hydraulic swing motor 2A and discharge the hydraulic oil discharged from the hydraulic swing motor 2A to the hydraulic oil tank.

The selector valve 174 is a spool valve for switching the flow of the hydraulic oil in order to supply the hydraulic oil discharged from the right main pump 14R to the bucket cylinder 9 and discharge the hydraulic oil in the bucket cylinder 9 to the hydraulic oil tank.

The selector valve 175L is a spool valve for switching the flow of the hydraulic oil in order to supply the hydraulic oil discharged from the left main pump 14L to the boom cylinder 7. The selector valve 175R is a spool valve that switches the flow of the hydraulic oil in order to supply the hydraulic oil discharged from the right main pump 14R to the boom cylinder 7 and discharge the hydraulic oil in the boom cylinder 7 to the hydraulic oil tank.

The selector valve 176L is a spool valve that switches the flow of hydraulic oil in order to supply hydraulic oil discharged from the left main pump 14L to the arm cylinder 8 and discharge the hydraulic oil in the arm cylinder 8 to a hydraulic oil tank.

The selector valve 176R is a spool valve that switches the flow of hydraulic oil in order to supply hydraulic oil discharged from the right main pump 14R to the arm cylinder 8 and discharge the hydraulic oil in the arm cylinder 8 to a hydraulic oil tank.

The left parallel line 42L is a working oil line in parallel with the left intermediate bypass line 40L. The left parallel line 42L is configured to be able to supply the hydraulic oil to the direction changing valve located further downstream when the flow of the hydraulic oil through the left intermediate bypass line 40L is restricted or blocked by any one of the direction changing valves 171, 173, and 175L. The right parallel line 42R is a working oil line in parallel with the right intermediate bypass line 40R. The right parallel line 42R is configured to be able to supply the hydraulic oil to the direction valve further downstream when the flow of the hydraulic oil through the right intermediate bypass line 40R is restricted or blocked by any one of the direction valves 172, 174, and 175R.

The control valve 177 is configured to have a variable opening area. In the present embodiment, the control valve 177 is a spool valve disposed in the left parallel conduit 42L, and is configured to be able to adjust the flow passage area of the left parallel conduit 42L. Specifically, the control valve 177 is disposed downstream of the branch point BP1 in the left parallel line 42L. This is because the flow rate of the hydraulic oil flowing into the arm cylinder 8 through the selector valve 176L is regulated by the control valve 177. The branch point BP1 is a point at which the line CD1 connecting the left parallel line 42L and the selector valve 175L branches off from the left parallel line 42L. The control valve 177 may also be disposed upstream of the branch point BP1 and downstream of the branch point BP2 in the left parallel line 42L. At this time, the control valve 177 can adjust the flow rate of the hydraulic oil flowing into the boom cylinder 7 through the selector valve 175L. The branch point BP2 is a point at which the line CD2 connecting the left parallel line 42L and the selector valve 173 branches off from the left parallel line 42L.

The control valve 177 is disposed upstream of the junction point JP1 in the conduit CD3 connecting the selector valve 176R and the bottom oil chamber of the arm cylinder 8. This is to avoid the flow of the hydraulic oil that flows from the right main pump 14R into the bottom oil chamber of the arm cylinder 8 through the selector valve 176R from being restricted by the control valve 177. The confluence point JP1 is a point at which the hydraulic oil that flows from the right main pump 14R into the bottom oil chamber of the arm cylinder 8 through the selector valve 176R and the hydraulic oil that flows from the left main pump 14L into the bottom oil chamber of the arm cylinder 8 through the selector valve 176L merge.

The solenoid valve 50 is configured to be able to operate the control valve 177. In the present embodiment, the solenoid valve 50 is a proportional solenoid valve that operates in response to a control command (e.g., a current command) from the controller 30, and is disposed in a conduit CD4 that is a pilot conduit connecting the control valve 177 and the pilot pump 15. The solenoid valve 50 is configured to be capable of adjusting the control pressure acting on the pilot port of the control valve 177 at a plurality of levels by the hydraulic oil discharged from the pilot pump 15. The solenoid valve 50 may be configured to be able to steplessly adjust a control pressure acting on a pilot port of the control valve 177.

In the present embodiment, the control valve 177 is an electromagnetic pilot type spool valve configured such that the larger the control pressure generated by the electromagnetic valve 50, the smaller the opening area. However, the control valve 177 may be a hydraulic pilot spool valve or an electromagnetic solenoid spool valve. In the case of an electromagnetic solenoid type spool valve, the electromagnetic valve 50 is omitted.

The regulator 13 includes a left regulator 13L and a right regulator 13R. The left regulator 13L controls the discharge rate of the left main pump 14L by adjusting the swash plate tilt angle of the left main pump 14L in accordance with the discharge pressure of the left main pump 14L. Specifically, the left regulator 13L reduces the discharge amount by adjusting the swash plate tilt angle of the left main pump 14L in accordance with, for example, an increase in the discharge pressure of the left main pump 14L. The same applies to the right regulator 13R. This is to prevent the absorbed power (e.g., absorption horsepower) of the main pump 14, which is expressed by the product of the discharge pressure and the discharge amount, from exceeding the output power (e.g., output horsepower) of the engine 11.

Operation device 26 includes a left operation lever 26L, a right operation lever 26R, and a travel lever 26D. The travel bar 26D includes a left travel bar 26DL and a right travel bar 26 DR.

The left operation lever 26L is used for the swing operation and the operation of the arm 5. When the control is performed in the forward/backward direction, the left control lever 26L causes a control pressure corresponding to the lever operation amount to act on the pilot port of the selector valve 176 by the hydraulic oil discharged from the pilot pump 15. When the control valve is operated in the left-right direction, the control pressure corresponding to the lever operation amount is applied to the pilot port of the selector valve 173 by the hydraulic oil discharged from the pilot pump 15.

Specifically, when the left operation lever 26L is operated in the arm closing direction, the hydraulic oil is introduced into the right pilot port of the direction switching valve 176L, and the hydraulic oil is introduced into the left pilot port of the direction switching valve 176R. When the left operation lever 26L is operated in the arm opening direction, the hydraulic oil is introduced into the left pilot port of the direction switching valve 176L, and the hydraulic oil is introduced into the right pilot port of the direction switching valve 176R. The left control lever 26L introduces hydraulic oil to the left pilot port of the selector valve 173 when operated in the leftward rotation direction, and introduces hydraulic oil to the right pilot port of the selector valve 173 when operated in the rightward rotation direction.

The right control lever 26R is used for the operation of the boom 4 and the operation of the bucket 6. When the right control lever 26R is operated in the front-rear direction, the control pressure corresponding to the lever operation amount is applied to the pilot port of the selector valve 175 by the hydraulic oil discharged from the pilot pump 15. When the control valve is operated in the left-right direction, the control pressure corresponding to the lever operation amount is applied to the pilot port of the selector valve 174 by the hydraulic oil discharged from the pilot pump 15.

Specifically, when the right control lever 26R is operated in the boom lowering direction, the hydraulic oil is introduced into the left pilot port of the selector valve 175R. When the right control lever 26R is operated in the boom raising direction, the hydraulic oil is introduced into the right pilot port of the selector valve 175L and the hydraulic oil is introduced into the left pilot port of the selector valve 175R. The right control lever 26R introduces hydraulic oil to the right pilot port of the direction valve 174 when operated in the bucket closing direction, and introduces hydraulic oil to the left pilot port of the direction valve 174 when operated in the bucket opening direction.

The traveling bar 26D is used for the operation of the crawler belt 1C. Specifically, the left travel lever 26DL is used for the operation of the left crawler belt 1 CL. The left travel lever 26DL may be configured to be linked with a left travel pedal. When the left travel lever 26DL is operated in the front-rear direction, the control pressure corresponding to the lever operation amount is applied to the pilot port of the selector valve 171 by the hydraulic oil discharged from the pilot pump 15. The right walking bar 26DR is used for the operation of the right crawler belt 1 CR. The right travel lever 26DR may be configured to be linked with a right travel pedal. When the right travel lever 26DR is operated in the forward/rearward direction, the control pressure corresponding to the lever operation amount is applied to the pilot port of the selector valve 172 by the hydraulic oil discharged from the pilot pump 15.

The discharge pressure sensor 28 includes a discharge pressure sensor 28L and a discharge pressure sensor 28R. The discharge pressure sensor 28L detects the discharge pressure of the left main pump 14L, and outputs the detected value to the controller 30. The same applies to the discharge pressure sensor 28R.

The operation pressure sensors 29 include operation pressure sensors 29LA, 29LB, 29RA, 29RB, 29DL, and 29 DR. The operation pressure sensor 29LA detects the content of the operation of the left operation lever 26L by the operator in the front-rear direction in a pressure form, and outputs the detected value to the controller 30. The operation contents include, for example, a lever operation direction and a lever operation amount (lever operation angle).

Similarly, the operation pressure sensor 29LB detects the content of the operation performed by the operator on the left operation lever 26L in the left-right direction in a pressure manner, and outputs the detected value to the controller 30. The operation pressure sensor 29RA detects the content of the operation of the right operation lever 26R in the front-rear direction by the operator in a pressure form, and outputs the detected value to the controller 30. The operation pressure sensor 29RB detects the content of the operation of the right operation lever 26R in the left-right direction by the operator in a pressure form, and outputs the detected value to the controller 30. The operation pressure sensor 29DL detects the content of the operation of the left travel lever 26DL by the operator in the front-rear direction in a pressure form, and outputs the detected value to the controller 30. The operation pressure sensor 29DR detects the content of the operation of the right travel lever 26DR in the front-rear direction by the operator in a pressure form, and outputs the detected value to the controller 30.

The controller 30 receives the output of the operating pressure sensor 29 and outputs a control command to the regulator 13 as needed to vary the discharge rate of the main pump 14. The controller 30 receives the output of the control pressure sensor 19 provided upstream of the throttle 18, and outputs a control command to the regulator 13 as necessary to change the discharge rate of the main pump 14. The throttle 18 includes a left throttle 18L and a right throttle 18R, and the control pressure sensor 19 includes a left control pressure sensor 19L and a right control pressure sensor 19R.

In the left intermediate bypass line 40L, a left choke 18L is disposed between the switching valve 176L located at the most downstream side and the hydraulic oil tank. Therefore, the flow of the hydraulic oil discharged from the left main pump 14L is restricted by the left throttle 18L. And, the left orifice 18L generates a control pressure for controlling the left regulator 13L. The left control pressure sensor 19L is a sensor for detecting the control pressure, and outputs the detected value to the controller 30. The controller 30 controls the discharge rate of the left main pump 14L by adjusting the swash plate tilt angle of the left main pump 14L in accordance with the control pressure. The controller 30 decreases the discharge rate of the left main pump 14L as the control pressure increases, and the controller 30 increases the discharge rate of the left main pump 14L as the control pressure decreases. The discharge rate of the right main pump 14R is controlled in the same manner.

Specifically, as shown in fig. 3, in the hydraulic system, when the hydraulic actuators in the shovel 100 are not operated in the standby state, the hydraulic oil discharged from the left main pump 14L passes through the left intermediate bypass line 40L and reaches the left throttle 18L. The flow of the hydraulic oil discharged from the left main pump 14L increases the control pressure generated upstream of the left throttle 18L. As a result, the controller 30 reduces the discharge rate of the left main pump 14L to the allowable minimum discharge rate, and suppresses the pressure loss (pumping loss) when the hydraulic oil discharged from the left main pump 14L passes through the left intermediate bypass line 40L. On the other hand, when any one of the hydraulic actuators is operated, the hydraulic oil discharged from the left main pump 14L flows into the operation target hydraulic actuator through the selector valve corresponding to the operation target hydraulic actuator. The flow of the hydraulic oil discharged from the left main pump 14L decreases or disappears the amount of hydraulic oil reaching the left throttle 18L, and the control pressure generated upstream of the left throttle 18L is reduced. As a result, the controller 30 increases the discharge rate of the left main pump 14L, circulates a sufficient amount of hydraulic oil in the hydraulic actuator to be operated, and ensures the driving of the hydraulic actuator to be operated. The controller 30 also controls the discharge rate of the right main pump 14R in the same manner.

According to the above configuration, the hydraulic system of fig. 3 can suppress unnecessary energy consumption in the main pump 14 in the standby state. Unnecessary energy consumption includes pumping loss of the working oil discharged from main pump 14 in intermediate bypass line 40. When the hydraulic actuator is operated, the hydraulic system of fig. 3 can reliably supply a sufficient amount of hydraulic oil required for the hydraulic actuator to be operated from the main pump 14.

Next, the information acquisition unit 30a and the control unit 30b, which are functional elements included in the controller 30, will be described. The information acquiring unit 30a is configured to acquire information related to the shovel 100. In the present embodiment, the information acquiring unit 30a is configured to acquire information related to the work content of the shovel 100 from at least one of the boom angle sensor S1, the arm angle sensor S2, the bucket angle sensor S3, the body inclination sensor S4, the turning angular velocity sensor S5, the cylinder pressure sensor, the turning pressure sensor, the travel pressure sensor, the boom cylinder stroke sensor, the arm cylinder stroke sensor, the bucket cylinder stroke sensor, the discharge pressure sensor 28, the operation pressure sensor 29, the space recognition device 70, the orientation detection device 71, the information input device 72, the positioning device 73, and the communication device. The cylinder pressure sensor includes, for example, at least one of a boom lever pressure sensor, a boom cylinder bottom pressure sensor, an arm lever pressure sensor, an arm cylinder bottom pressure sensor, a bucket lever pressure sensor, and a bucket cylinder bottom pressure sensor.

The information related to the work content of the shovel 100 includes, for example, information related to a work performed by the shovel 100. The work performed by the excavator 100 includes, for example, turning press excavation, aerial boom closing turning, aerial boom opening turning, aerial boom raising turning, aerial boom lowering turning, aerial bucket closing turning, aerial bucket opening turning, and the like. The aerial boom closing swing is an operation of closing the boom 5 in the aerial and swinging the upper swing body 3. The same applies to the aerial boom opening swing, the aerial boom raising swing, the aerial boom lowering swing, the aerial bucket closing swing, the aerial bucket opening swing, and the like.

The information acquiring unit 30a acquires, for example, at least one of a boom angle, an arm angle, a bucket angle, a body tilt angle, a swing angular velocity, an arm pressure, a boom cylinder bottom pressure, an arm rod pressure, an arm cylinder bottom pressure, an arm rod pressure, a bucket cylinder bottom pressure, a swing pressure, a traveling pressure, a boom stroke amount, an arm stroke amount, a bucket stroke amount, a discharge pressure of the main pump 14, an operation pressure of the operation device 26, information on a three-dimensional space object existing around the excavator 100, information on a relative relationship between the orientation of the upper revolving unit 3 and the orientation of the lower traveling unit 1, information input to the controller 30, and information on the current position as information on the work content of the excavator 100.

The control unit 30b is configured to be able to control the operation of the shovel 100 based on information related to the work content of the shovel 100. In the present embodiment, the control unit 30b is configured to be able to adjust the opening area of the control valve 177 to a value suitable for the rotary-push excavation when the rotary-push excavation is performed. Further, the control unit 30b is configured to be able to adjust the opening area of the control valve 177 to a value suitable for the closing and rotation of the aerial boom when the aerial boom is closed and rotated.

Here, details of the control by the control unit 30b when a combined operation including the arm closing operation and the right swing operation is performed will be described with reference to fig. 4 and 5. Fig. 4 shows the relationship between the right rotary pilot pressure Pi acting on the right pilot port of the selector valve 173 and the opening area Sa of the control valve 177. Fig. 5 is a flowchart of an example of a process (hereinafter, referred to as "adjustment process") in which the controller 30 adjusts the opening area Sa of the control valve 177. The controller 30 repeatedly executes the adjustment processing at a predetermined control cycle.

First, the controller 30 determines whether or not the arm closing operation is performed (step ST 1). In the present embodiment, the control unit 30b of the controller 30 determines whether or not the arm closing operation is performed based on the output of the operation pressure sensor 29LA as the information acquisition unit 30 a. When the electric lever is used, the controller 30 determines whether or not the arm closing operation is performed based on the electric signal output from the left lever 26L.

When determining that the arm closing operation has been performed (yes at step ST1), the controller 30 determines whether or not the swing operation has been performed (step ST 2). In the present embodiment, the control unit 30b of the controller 30 determines whether or not the swing operation is performed based on the output of the operation pressure sensor 29LB serving as the information acquisition unit 30 a. When the electric operation lever is used, the controller 30 determines whether or not the swing operation is performed based on the electric signal output from the left operation lever 26L.

When it is determined that the swing operation has been performed (yes at step ST2), the controller 30 determines whether or not the discharge pressure Pp of the left main pump 14L is equal to or higher than a predetermined threshold value TH (step ST 3). In the present embodiment, when it is determined that the swing operation is performed, that is, when it is determined that the combined operation of the arm closing operation and the swing operation is performed, the control unit 30b of the controller 30 executes step ST 3. Specifically, the control unit 30b determines whether or not the discharge pressure Pp of the left main pump 14L is equal to or greater than the threshold value TH based on the output of the discharge pressure sensor 28L as the information acquisition unit 30 a. The threshold TH is stored in advance in the NVRAM.

In the present embodiment, the controller 30 performs the determination of step ST2 after performing the determination of step ST1, but the order of step ST1 and step ST2 is different. That is, the controller 30 may perform the determination at step ST1 after performing the determination at step ST2, or may perform the determination at step ST1 and the determination at step ST2 at the same time. The determination at step ST1 may be omitted.

When it is determined that the discharge pressure Pp of the left main pump 14L is equal to or higher than the predetermined threshold value TH (yes in step ST3), the controller 30 adopts the 1 ST mode PT1 as the change mode of the opening area Sa of the control valve 177 (step ST 4). In the present embodiment, the control unit 30b of the controller 30 determines that the turning/pressing excavation is performed when determining that the discharge pressure Pp of the left main pump 14L is equal to or greater than the predetermined threshold value TH. Then, the control unit 30b outputs a control command to the solenoid valve 50, for example, to reduce the opening area of the control valve 177 to a value suitable for the swing-push excavation (a value determined by the 1 st mode PT 1).

The pattern of change in the opening area Sa of the control valve 177 is a pattern showing the correspondence relationship between the rightward turning pilot pressure Pi and the opening area Sa of the control valve 177. In the present embodiment, the 1 st mode PT1 is the mode shown by the solid line in fig. 4, and is stored in the NVRAM by reference. In the 1 st mode PT1, the opening area Sa becomes the reference value Sa3 when the right rotary pilot pressure Pi is smaller than the value Pi1, decreases to the 1 st set value Sa1 as the right rotary pilot pressure Pi increases when the right rotary pilot pressure Pi is greater than or equal to the value Pi1 and smaller than the value Pi3, and becomes the 1 st set value Sa1 when the right rotary pilot pressure Pi is greater than or equal to the value Pi 3. The reference value Sa3 corresponds to the opening area of the control valve 177 when the swing operation is not performed.

The control unit 30b of the controller 30 determines the current right swing pilot pressure Pic from the output of the operation pressure sensor 29LB, and derives the opening area Sac1 corresponding to the current right swing pilot pressure Pic with reference to the 1 st mode PT 1. Then, the controller 30b outputs a control command corresponding to the derived opening area Sac1 to the solenoid valve 50, and adjusts the opening area of the control valve 177 to the opening area Sac 1. Control commands corresponding to the respective values of the opening area Sa are typically stored in advance in the NVRAM or the like.

When determining that the discharge pressure Pp of the left main pump 14L is smaller than the predetermined threshold value TH (no in step ST3), the controller 30 adopts the 2 nd mode PT2 as the change mode of the opening area Sa of the control valve 177 (step ST 5). In the present embodiment, the control unit 30b of the controller 30 determines that the boom closing rotation is performed when determining that the discharge pressure Pp of the left main pump 14L is smaller than the predetermined threshold value TH. Then, the controller 30b outputs a control command to the solenoid valve 50, for example, to reduce the opening area of the control valve 177 to a value suitable for the aerial boom closing rotation (value determined in the 2 nd mode PT 2). The value for the aerial stick closure swing is typically greater than the value for the swing press dig.

In the present embodiment, the 2 nd mode PT2 is the mode shown by the one-dot chain line in fig. 4, and is stored in the NVRAM by reference. In the 2 nd mode PT2, the opening area Sa becomes the reference value Sa3 when the right rotary pilot pressure Pi is smaller than the value Pi2, decreases to the 2 nd set value Sa2 as the right rotary pilot pressure Pi increases when the right rotary pilot pressure Pi is greater than or equal to the value Pi2 and smaller than the value Pi3, and becomes the 2 nd set value Sa2 when the right rotary pilot pressure Pi is greater than or equal to the value Pi 3. The control unit 30b of the controller 30 determines the current right swing pilot pressure Pic from the output of the operation pressure sensor 29LB, and derives the opening area Sac2 corresponding to the current right swing pilot pressure Pic with reference to the 2 nd mode PT 2. Then, the controller 30b outputs a control command corresponding to the derived opening area Sac2 to the solenoid valve 50, and adjusts the opening area of the control valve 177 to the opening area Sac 2.

When it is determined that the arm closing operation is not performed (no at step ST1) or when it is determined that the swing operation is not performed (no at step ST2), that is, when it is determined that the combined operation of the arm closing operation and the swing operation is not performed, the controller 30 adopts the reference mode PT3 as the change mode of the opening area Sa of the control valve 177 (step ST 6). In the present embodiment, when determining that the arm closing is performed alone, the control unit 30b of the controller 30 outputs a control command to the solenoid valve 50 to set the opening area of the control valve 177 to a value suitable for the arm closing (a value determined in the reference mode PT 3).

In the present embodiment, the reference mode PT3 is the mode shown by the broken line in fig. 4, and is stored in the NVRAM with reference. In the reference mode PT3, the opening area Sa becomes the reference value Sa3 regardless of the magnitude of the right-turn pilot pressure Pi. The controller 30b of the controller 30 outputs a control command corresponding to the reference value Sa3 to the solenoid valve 50, and adjusts the opening area of the control valve 177 to the reference value Sa 3.

In this way, the controller 30 can control the opening area Sa of the control valve 177 based on the information on the work content, so that the excavator 100 can perform an operation suitable for the work content. Specifically, when it is determined that the rolling excavation is performed, the controller 30 can adjust the opening area Sa of the control valve 177 to a value suitable for the rolling excavation. When it is determined that the boom closing swing is performed, the controller 30 can adjust the opening area Sa of the control valve 177 to a value suitable for the boom closing swing.

As described above, the shovel 100 according to the embodiment of the present invention includes: a lower traveling body 1; an upper revolving structure 3 which is rotatably mounted on the lower traveling structure 1; a left main pump 14L as a1 st hydraulic pump provided in the upper slewing body 3; an excavation attachment AT as an attachment mounted on the upper slewing body 3; a swing hydraulic motor 2A as a1 st actuator; an arm cylinder 8 as a2 nd actuator; a direction change valve 173 as a1 st direction change valve corresponding to the turning hydraulic motor 2A; a direction change valve 176L as a2 nd direction change valve corresponding to the arm cylinder 8; a left intermediate bypass line 40L as a1 st line connecting the left main pump 14L and the selector valve 173; a left parallel line 42L as a2 nd line connecting the left intermediate bypass line 40L and the selector valve 176L; a control valve 177 provided on the left parallel line 42L; and a controller 30 as a control device for controlling the opening area Sa of the control valve 177 based on information on the operation contents.

With this configuration, the shovel 100 can stabilize the operation of the shovel during a combined operation including a turning operation. For example, the shovel 100 can stabilize the operation of the shovel 100 when performing swing-down excavation or aerial boom closing swing by a combined operation including a boom closing operation and a swing operation. This is because the controller 30 can control the opening area Sa of the control valve 177 to a value suitable for the swing-push excavation when the swing-push excavation is performed. Further, the controller 30 can control the opening area Sa of the control valve 177 to a value suitable for the aerial boom closing and turning when the aerial boom closing and turning is performed.

In other words, this is because the controller 30 can prevent the opening area Sa of the control valve 177 from being adjusted to a value suitable for the swing-press excavation when the aerial boom closing swing is performed. When the opening area Sa of the control valve 177 is adjusted to a value suitable for the swing-push excavation at the time of the aerial boom closing swing, the flow rate of the hydraulic oil to the bottom oil chamber of the boom cylinder 8 may be insufficient. This is because, although the volume of the bottom oil chamber of the arm cylinder 8 tends to increase when the arm 5 drops in the closing direction due to its own weight, the flow rate of the hydraulic oil to the bottom oil chamber of the arm cylinder 8 is restricted by the control valve 177. With the above configuration, the shovel 100 can prevent such a shortage from occurring.

The 2 nd actuator is an actuator for operating an attachment, and may be a boom cylinder 7. At this time, the 2 nd direction valve may be the direction valve 175L.

The left parallel line 42L as the 2 nd line is configured to connect a portion of the left intermediate bypass line 40L as the 1 st line located upstream of the direction changing valve 173 as the 1 st direction changing valve and the direction changing valve 176L as the 2 nd direction changing valve. That is, the left parallel line 42L as the 2 nd line is configured such that the hydraulic oil discharged from the left main pump 14L can bypass the selector valve 173 as the 1 st selector valve without passing through it.

The controller 30 is preferably configured to determine the operation content based on the discharge pressure Pp of the left main pump 14L. For example, when a combined operation including an arm closing operation and a turning operation is performed, the controller 30 determines that turning push excavation is performed when the discharge pressure Pp is a predetermined threshold value TH, and determines that airborne arm closing turning is performed when the discharge pressure Pp is smaller than the predetermined threshold value TH. With this configuration, the controller 30 can easily determine the work content of the excavator. However, the controller 30 may determine the work content based on at least one of an image captured by a camera as the front sensor 70F, and a value output by a cylinder pressure sensor, and a posture detection device that detects the posture of the attachment.

The controller 30 may set the opening area Sa of the control valve 177 to the 1 st set value Sa1 smaller than a predetermined reference value Sa3 when a combined operation including a swing operation and an attachment operation is performed and when a load on the swing actuator or the attachment actuator is equal to or greater than a predetermined threshold value. In addition, the load associated with the swing actuator or the accessory actuator may be detected or calculated as a load relative to the main pump 14, or may be detected or calculated as a load relative to the engine 11. For example, when the controller 30 performs a combined operation including a swing operation and an arm closing operation, and when it determines that the discharge pressure of the left main pump 14L is equal to or greater than the predetermined threshold value TH and that the swing-pressing excavation is performed, the opening area Sa at which the right swing pilot pressure Pi is the value Pid may be set to the 1 st set value Sa1, as shown in fig. 4.

With this configuration, the controller 30 can increase the flow rate and pressure of the hydraulic oil to the swing hydraulic motor 2A by restricting the flow of the hydraulic oil to the bottom oil chamber of the arm cylinder 8 by setting the opening area Sa of the control valve 177 to the 1 st set value Sa 1. Therefore, the controller 30 can prevent most of the hydraulic oil discharged from the left main pump 14L from flowing into the bottom oil chamber of the arm cylinder 8 during the turning-pressing excavation, and the flow rate of the hydraulic oil to the turning hydraulic motor 2A from excessively decreasing. As a result, the operator of the excavator 100 can smoothly perform the turning-pushing excavation.

The controller 30 may set the opening area Sa of the control valve 177 to the 2 nd set value Sa2 smaller than the reference value Sa3 and larger than the 1 st set value Sa1 when a combined operation including a swing operation and an operation of an attachment is performed and a load on the swing actuator or the attachment actuator is smaller than a predetermined threshold value. For example, when the controller 30 determines that the boom closing swing is performed when the combined operation including the swing operation and the arm closing operation is performed and the discharge pressure of the left main pump 14L is less than the predetermined threshold value TH, the opening area Sa when the right swing pilot pressure Pi is the value Pid may be set to the 2 nd set value Sa2 as shown in fig. 4.

With this configuration, controller 30 can prevent the flow of hydraulic oil to the bottom oil chamber of arm cylinder 8 from being excessively restricted when the aerial arm is closed and rotated. Therefore, the controller 30 can prevent the flow rate of the hydraulic oil to the bottom oil chamber of the arm cylinder 8 from being excessively reduced when the aerial arm is closed and rotated. As a result, the operator of the excavator 100 can smoothly perform the aerial boom closing and turning.

The reference value Sa3 is preferably the opening area of the control valve 177 when the swing operation is not performed. Therefore, the 2 nd set value Sa2 is larger than the opening area when performing the swing/push excavation, but smaller than the opening area when not performing the swing operation, that is, when closing the aerial boom by performing the boom closing operation alone.

Therefore, the controller 30 is in a state in which the flow of hydraulic oil to the bottom oil chamber of the arm cylinder 8 is restricted as compared with the case of closing the aerial boom, but is in a state in which the restriction is relaxed as compared with the case of performing the swing-push excavation, and can perform the aerial boom closing swing. As a result, the controller 30 can cause an appropriate amount of hydraulic oil to flow into the swing hydraulic motor 2A and the arm cylinder 8 at appropriate pressures when the aerial boom is closed and swiveled, and can improve the operability when the aerial boom is closed and swiveled.

The attachment actuator may be a boom cylinder 7 or a bucket cylinder 9. At this time, the swing-push excavation may be excavation that is achieved by a combined operation including a swing operation and a boom raising operation or a boom lowering operation, and by moving the boom 4 while pressing the side surface of the bucket 6 against the excavation target. The controller 30 may be configured to be able to discriminate between the swing-pushing excavation and the boom raising swing or the boom lowering swing. Alternatively, the swing-press excavation may be excavation that is performed by a combined operation including a swing operation and a bucket closing operation or a bucket opening operation, and by moving the bucket 6 while pressing the side surface of the bucket 6 against an excavation target. The controller 30 may be configured to be able to discriminate between the swing-push excavation and the air bucket closing swing or the air bucket opening swing. Alternatively, the swing-press excavation may be excavation that is performed by a combined operation including a swing operation and an arm opening operation, and that is performed by opening the arm 5 while pressing the side surface of the bucket 6 against the excavation target. The controller 30 may be configured to be able to discriminate between the swing-push excavation and the opening and swing of the arm.

The shovel 100 preferably has a pilot pump 15 and a solenoid valve 50. The solenoid valve 50 is disposed on a conduit CD4 connecting the control valve 177 and the pilot pump 15. With this simple configuration, the shovel 100 can stabilize the operation of the shovel 100 when performing a combined operation including a turning operation.

The shovel 100 preferably includes a right main pump 14R as a2 nd hydraulic pump different from the left main pump 14L, a direction change valve 176R as a3 rd direction change valve different from the direction change valve 176L corresponding to the arm cylinder 8, and a pipe line CD3 connecting the arm cylinder 8 and the direction change valve 176R. The conduit CD3 includes a merging point JP1 at which the hydraulic oil discharged from the left main pump 14L and the hydraulic oil discharged from the right main pump 14R merge together. The control valve 177 is disposed upstream of the confluence point JP 1.

With this configuration, the shovel 100 can appropriately supply the hydraulic oil discharged from the left main pump 14L to the slewing hydraulic motor 2A without unnecessarily restricting the flow of the hydraulic oil discharged from the right main pump 14R.

The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above embodiments. The above-described embodiment can be applied to various modifications, replacements, and the like without departing from the scope of the present invention. Further, the features described separately can be combined as long as technically contradictory results are not generated.

For example, the controller 30 may limit the magnitude of the fluctuation of the control command to the solenoid valve 50. This is to prevent the opening area Sa of the control valve 177 from suddenly changing and causing unstable operation of the shovel 100 when the mode of change of the opening area Sa is switched among the 1 st mode PT1, the 2 nd mode PT2, and the reference mode PT 3.

The hydraulic system mounted on the shovel 100 may be configured as shown in fig. 6. Fig. 6 shows another configuration example of the hydraulic system mounted on the shovel 100. Fig. 6 shows the mechanical power transmission system, the hydraulic oil line, the pilot line, and the electric control system by double lines, solid lines, broken lines, and dotted lines, respectively, as in fig. 3.

The hydraulic system shown in fig. 6 differs from the hydraulic system shown in fig. 3 mainly in that it includes the proportional valve 31, the line 43, and the bleed valve 178, but is otherwise the same as the hydraulic system shown in fig. 3. Therefore, the description of the same parts will be omitted below, and the detailed description of different parts will be given.

The hydraulic system shown in fig. 6 includes a line 43 instead of the intermediate bypass line 40 and the parallel line 42 in the hydraulic system shown in fig. 3.

The line 43 includes a left line 43L and a right line 43R. The left line 43L is a hydraulic oil line that connects the directional control valves 171, 173, 175L, and 176L disposed in the control valve unit 17 in parallel between the left main pump 14L and the hydraulic oil tank, respectively. The right line 43R is a hydraulic oil line that connects the directional control valves 172, 174, 175R, and 176R arranged in the control valve unit 17 in parallel between the right main pump 14R and the hydraulic oil tank, respectively.

The bleed-off valve 178 controls the flow rate (hereinafter referred to as "bleed-off flow rate") of the hydraulic oil flowing to the hydraulic oil tank without passing through the hydraulic actuator, among the hydraulic oil discharged from the main pump 14. The bleed valve 178 may also be arranged inside the control valve unit 17.

Specifically, the bleed valve 178 is a spool valve that controls a bleed flow rate of the hydraulic oil discharged from the main pump 14. In the example shown in fig. 6, the bleed valves 178 include a left bleed valve 178L and a right bleed valve 178R. The left relief valve 178L is a spool valve that controls a relief flow rate of the hydraulic oil discharged from the left main pump 14L. The right relief valve 178R is a spool valve that controls a relief flow rate of the hydraulic oil discharged from the right main pump 14R.

The bleed valve 178 is configured to be movable between, for example, the 1 st valve position with a minimum opening area (opening degree 0%) and the 2 nd valve position with a maximum opening area (opening degree 100%). In the example shown in fig. 6, the bleed valve 178 is configured to be steplessly movable between the 1 st valve position and the 2 nd valve position.

The proportional valve 31 is configured to operate in accordance with a control command output from the controller 30. In the example shown in fig. 6, the proportional valve 31 is a solenoid valve that adjusts the secondary pressure introduced from the pilot pump 15 to the pilot port of the bleed valve 178 in accordance with a current command output by the controller 30. For example, the proportional valve 31 operates such that the secondary pressure introduced into the pilot port of the bleed valve 178 increases as the supplied current increases.

The controller 30 is configured to be able to change the opening area of the bleed valve 178 by outputting a current command to the proportional valve 31 as necessary.

Specifically, the proportional valve 31 is configured to be able to adjust the secondary pressure introduced from the pilot pump 15 to the pilot port of the bleed valve 178 in accordance with a current command output by the controller 30. In the example shown in fig. 6, the proportional valve 31 includes a left proportional valve 31L and a right proportional valve 31R. The left proportional valve 31L is capable of regulating the secondary pressure so that the left bleed valve 178L can stop at any position between the 1 st and 2 nd valve positions. The right proportional valve 31R is capable of regulating the secondary pressure so that the right bleed valve 178R can stop at any position between the 1 st and 2 nd valve positions.

Next, negative control employed in the hydraulic system shown in fig. 6 will be described. In the conduit 43, an orifice 18 is disposed between a drain valve 178, which is a slide valve located at the most downstream side, and the hydraulic oil tank. The flow of the working oil to the working oil tank through the bleed valve 178 is restricted by the choke 18. The throttle 18 generates a control pressure for controlling the regulator 13, that is, a control pressure for controlling the discharge rate of the main pump 14. The control pressure sensor 19 is a sensor for detecting a control pressure, and outputs a detected value to the controller 30.

In the example shown in fig. 6, the choke 18 is a fixed choke having a constant opening area, and includes a left choke 18L disposed between the left drain valve 178L and the hydraulic oil tank in the left pipe line 43L, and a right choke 18R disposed between the right drain valve 178R and the hydraulic oil tank in the right pipe line 43R. The control pressure sensor 19 includes: a left control pressure sensor 19L that detects a control pressure generated by the left orifice 18L to control the left regulator 13L; and a right control pressure sensor 19R that detects a control pressure generated by the right orifice 18R for controlling the right regulator 13R.

The controller 30 controls the discharge amount (displacement) of the main pump 14 by adjusting the swash plate tilt angle of the main pump 14 in accordance with the control pressure. The relationship between the control pressure and the discharge rate of the main pump 14 is referred to as "negative control characteristic". The control of the discharge amount based on the negative control characteristic may be realized by using a reference table stored in a ROM or the like, or may be realized by executing a predetermined calculation in real time. In the example shown in fig. 6, the controller 30 refers to a reference table indicating predetermined negative control characteristics, and decreases the discharge rate of the main pump 14 as the control pressure increases, and increases the discharge rate of the main pump 14 as the control pressure decreases.

Specifically, as shown in fig. 6, when neither the operating device 26 is operated nor the hydraulic actuator is operated, that is, when the hydraulic system is in a standby state, the hydraulic oil discharged from the left main pump 14L reaches the left throttle 18L through the left relief valve 178L. When the flow rate of the hydraulic oil reaching the left orifice 18L is equal to or greater than the predetermined flow rate, the control pressure generated upstream of the left orifice 18L reaches the predetermined pressure. When the control pressure reaches the predetermined pressure, the controller 30 reduces the discharge rate of the left main pump 14L to a predetermined allowable minimum discharge rate, and suppresses a pressure loss (pumping loss) when the discharged hydraulic oil passes through the left pipe passage 43L. This predetermined allowable minimum discharge amount in the standby state is referred to as a "standby flow amount". Controller 30 also controls the discharge rate of right main pump 14R in the same manner.

On the other hand, when any one of the hydraulic actuators is operated, the hydraulic oil discharged from the left main pump 14L flows into the operation target hydraulic actuator through the selector valve corresponding to the operation target hydraulic actuator. The controller 30 outputs a control command to the left proportional valve 31L to reduce the opening area of the left bleed valve 178L in accordance with the movement amount of the directional valve corresponding to the hydraulic actuator to be operated. The shift amount of the direction valve corresponds to a control pressure applied to a pilot port of the direction valve. When the plurality of direction switching valves are simultaneously moved, the controller 30 decreases the opening area of the left bleed valve 178L in accordance with the total movement amount of the plurality of direction switching valves. The controller 30 is typically configured to decrease the opening area of the left bleed valve 178L as the total movement amount of the switching valves increases. At this time, the flow rate of the hydraulic oil reaching the left orifice 18L through the left relief valve 178L decreases, and the control pressure generated upstream of the left orifice 18L decreases. As a result, the controller 30 increases the discharge rate of the left main pump 14L, supplies sufficient hydraulic oil to the operation target hydraulic actuator, and ensures the driving of the operation target hydraulic actuator. Controller 30 also controls the discharge rate of right main pump 14R in the same manner. The flow rate of the working oil flowing into the hydraulic actuator is referred to as "actuator flow rate". The flow rate of the hydraulic oil discharged from the left main pump 14L corresponds to the sum of the actuator flow rate associated with the left line 43L and the bleed-off flow rate associated with the left line 43L. The same applies to the flow rate of the hydraulic oil discharged from right main pump 14R.

According to the above configuration, when the hydraulic actuator is operated, the hydraulic system shown in fig. 6 can reliably supply a sufficient amount of hydraulic oil required from the main pump 14 to the hydraulic actuator to be operated. Also, the hydraulic system shown in fig. 6 can suppress unnecessary consumption of hydraulic energy in the standby state. This is because the bleed-off flow can be reduced to the standby flow. The same applies to the hydraulic system shown in fig. 3.

In the example shown in fig. 6, the control valve 177 is disposed in a line CD5 connecting the left line 43L and the direction valve 176L.

In this configuration, when the aerial boom is closed and rotated or rotated and pushed to dig, the controller 30 outputs a control command to the left proportional valve 31L to reduce the opening area of the left bleed valve 178L. At this time, the opening area of the left relief valve 178L is set to a size corresponding to the amount of movement of the direction switching valve 173 corresponding to the swing hydraulic motor 2A and the amount of movement of the direction switching valve 176 corresponding to the arm cylinder 8. When it is determined that the rolling excavation is performed, the controller 30 outputs a control command to the solenoid valve 50 to change the opening area of the control valve 177 to a value suitable for the rolling excavation. Therefore, when it is determined that the swing-push excavation is performed, the controller 30 can reduce the flow rate of the hydraulic oil flowing into the selector valve 176L as compared with the case where it is determined that the boom closing rotation is performed. On the contrary, when determining that the boom closing rotation is performed, the controller 30 outputs a control command to the solenoid valve 50 to change the opening area of the control valve 177 to a value suitable for the boom closing rotation. Therefore, when it is determined that the boom closing and turning is performed, the controller 30 can increase the flow rate of the hydraulic oil flowing into the selector valve 176L as compared with the case of determining that the turning and pressing excavation is performed.

With this configuration, the hydraulic system shown in fig. 6 can achieve the same effects as those of the hydraulic system shown in fig. 3. Specifically, the hydraulic system shown in fig. 6 can stabilize the operation of the shovel 100 when performing the swing-push excavation or the closing and turning of the arm.

Further, an electric operation system may be mounted on the shovel 100 instead of the hydraulic operation system. Fig. 7 shows a configuration example of the motor-driven operation system. Specifically, the electric operation system of fig. 7 is an example of a swing operation system, and is mainly composed of a pilot pressure operated control valve unit 17, a left operation lever 26L as an electric operation lever, a controller 30, a left swing operation solenoid valve 65, and a right swing operation solenoid valve 66. The electric operation system of fig. 7 can be similarly applied to a boom operation system, an arm operation system, a bucket operation system, a travel operation system, and the like.

As shown in fig. 3, the pilot pressure operation type control valve unit 17 includes a direction change valve 171 associated with the left traveling hydraulic motor 2ML, a direction change valve 172 associated with the right traveling hydraulic motor 2MR, a direction change valve 173 associated with the swing hydraulic motor 2A, a direction change valve 174 associated with the bucket cylinder 9, a direction change valve 175 associated with the boom cylinder 7, a direction change valve 176 associated with the arm cylinder 8, and the like. The solenoid valve 65 is configured to be able to adjust the flow path area of a pipe line connecting the pilot pump 15 and the left pilot port of the selector valve 173. The solenoid valve 66 is configured to be able to adjust the flow path area of a conduit connecting the pilot pump 15 and the right pilot port of the selector valve 173.

When the manual operation is performed, the controller 30 generates a left-turning operation signal (electric signal) or a right-turning operation signal (electric signal) from the operation signal (electric signal) output from the operation signal generating unit of the left operation lever 26L. The operation signal output from the operation signal generating unit of the left operation lever 26L is an electric signal that changes in accordance with the operation direction and the operation amount of the left operation lever 26L.

Specifically, when the left operation lever 26L is operated in the left swiveling direction, the controller 30 outputs a left swiveling operation signal (electric signal) corresponding to the lever operation amount to the solenoid valve 65. The solenoid valve 65 adjusts the flow path area in response to the left swing operation signal (electric signal), and controls the pilot pressure acting on the left pilot port of the selector valve 173 as the left swing operation signal (pressure signal). Similarly, when the left operating lever 26L is operated in the rightward turning direction, the controller 30 outputs a right turning operation signal (electric signal) corresponding to the lever operation amount to the solenoid valve 66. The solenoid valve 66 adjusts the flow path area in accordance with the right swing operation signal (electric signal), and controls the pilot pressure acting on the right pilot port of the selector valve 173 as the right swing operation signal (pressure signal).

In the case of executing the autonomous control function, the controller 30 generates a left swing operation signal (electric signal) or a right swing operation signal (electric signal) from the autonomous control signal (electric signal), for example, instead of the operation signal (electric signal) output from the operation signal generating section of the left operation lever 26L. The autonomous control function is a function for autonomously operating the shovel 100, and includes, for example, a function for autonomously operating a hydraulic actuator regardless of the content of the operation device 26 by the operator. The autonomous control signal may be an electric signal generated by the controller 30, or may be an electric signal generated by an external control device or the like other than the controller 30.

Here, the details of the control by the control unit 30b when the composite operation including the arm closing operation and the right swing operation is performed using the electric operation system will be described with reference to fig. 8. Fig. 8 is a diagram showing a relationship between the right swing operation signal (electric signal) Si output to the solenoid valve 66 and the opening area Sa of the control valve 177, and corresponds to fig. 4.

When the control unit 30b determines that the turning/pushing excavation is performed, the 1 st mode PT1 is adopted as the mode of changing the opening area Sa of the control valve 177, as in the case of the hydraulic operation system. Then, the control unit 30b outputs a control command to the solenoid valve 50 to reduce the opening area of the control valve 177 to a value suitable for the swing-push excavation (a value determined by the 1 st mode PT1 of fig. 8).

The pattern of change in the opening area Sa of the control valve 177 is a pattern showing the correspondence relationship between the right swing operation signal (electric signal) Si and the opening area Sa of the control valve 177. The 1 st mode PT1 is the mode shown by the solid line in fig. 8, and is stored in the NVRAM by reference. In the 1 st mode PT1, the opening area Sa becomes the reference value Sa3 when the right swing operation signal (electric signal) Si is smaller than the value Si1, decreases to the 1 st setting value Sa1 as the right swing operation signal (electric signal) Si increases when the right swing operation signal (electric signal) Si is equal to or larger than the value Si1 and smaller than the value Si3, and becomes the 1 st setting value Sa1 when the right swing operation signal (electric signal) Si is equal to or larger than the value Si 3. The reference value Sa3 corresponds to the opening area of the control valve 177 when the swing operation is not performed.

The controller 30b determines the current right swing operation signal (electric signal) Sic from the output of the left operation lever 26L, and derives the opening area Sac1 corresponding to the current right swing operation signal (electric signal) Sic with reference to the 1 st mode PT 1. Then, the controller 30b outputs a control command corresponding to the derived opening area Sac1 to the solenoid valve 50, and adjusts the opening area of the control valve 177 to the opening area Sac 1. Control commands corresponding to the respective values of the opening area Sa are typically stored in advance in the NVRAM or the like.

When determining that the boom closing and turning is performed, the controller 30b adopts a2 nd mode PT2 of fig. 8 as a mode of changing the opening area Sa of the control valve 177. Then, the controller 30b outputs a control command to the solenoid valve 50 to reduce the opening area of the control valve 177 to a value suitable for the aerial boom closing rotation (value determined in the 2 nd mode PT 2). The value for the aerial stick closure swing is typically greater than the value for the swing press dig.

The 2 nd mode PT2 is the mode shown by the one-dot chain line of fig. 8, and is stored in the NVRAM by reference. In the 2 nd mode PT2, the opening area Sa becomes the reference value Sa3 when the right swing operation signal (electric signal) Si is smaller than the value Si2, decreases to the 2 nd setting value Sa2 as the right swing operation signal (electric signal) Si increases when the right swing operation signal (electric signal) Si is equal to or larger than the value Si2 and smaller than the value Si3, and becomes the 2 nd setting value Sa2 when the right swing operation signal (electric signal) Si is equal to or larger than the value Si 3.

The controller 30b determines the current right swing operation signal (electric signal) Sic from the output of the left operation lever 26L, and derives the opening area Sac2 corresponding to the current right swing operation signal (electric signal) Sic with reference to the 2 nd mode PT 2. Then, the controller 30b outputs a control command corresponding to the derived opening area Sac2 to the solenoid valve 50, and adjusts the opening area of the control valve 177 to the opening area Sac 2.

When determining that the arm closing is performed alone, the controller 30b outputs a control command to the solenoid valve 50 to set the opening area of the control valve 177 to a value suitable for the arm closing (a value determined by the reference pattern PT3 in fig. 8).

The reference mode PT3 is a mode shown by a broken line in fig. 8, and is stored in the NVRAM by reference. In the reference mode PT3, the opening area Sa becomes the reference value Sa3 regardless of the magnitude of the right swing operation signal (electric signal) Si. The controller 30b outputs a control command corresponding to the reference value Sa3 to the solenoid valve 50, and adjusts the opening area of the control valve 177 to the reference value Sa 3.

In this way, even when the electric operation system is used, the controller 30 can control the opening area Sa of the control valve 177 based on the information on the work content, so that the excavator 100 can perform the operation suitable for the work content, as in the case of using the hydraulic operation system. Specifically, when it is determined that the rolling excavation is performed, the controller 30 can adjust the opening area Sa of the control valve 177 to a value suitable for the rolling excavation. When it is determined that the boom closing swing is performed, the controller 30 can adjust the opening area Sa of the control valve 177 to a value suitable for the boom closing swing.

The hydraulic system mounted on the shovel 100 may be configured as shown in fig. 9. Fig. 9 shows another configuration example of the hydraulic system mounted on the shovel 100. Fig. 9 shows the mechanical power transmission system, the hydraulic oil line, the pilot line, and the electric control system by double lines, solid lines, broken lines, and dotted lines, respectively, as in fig. 3.

The hydraulic system shown in fig. 9 is different from the hydraulic system shown in fig. 3 mainly in that an electric operating system is mounted instead of the hydraulic operating system, but is otherwise the same as the hydraulic system shown in fig. 3. Therefore, the description of the same parts will be omitted below, and the detailed description of different parts will be given.

In the hydraulic system shown in fig. 9, the direction change valves 171 to 176 are each constituted by an electromagnetic spool valve. The direction change valves 171 to 176 are configured to operate in accordance with a control command from the controller 30. Therefore, in the hydraulic system shown in fig. 9, the solenoid valve 50, the control valve 177, and the line CD4 in the hydraulic system shown in fig. 3 are omitted. This is because the controller 30 can operate the direction switching valve 176L regardless of the operation direction and the operation amount of the left operation lever 26L.

Specifically, the controller 30 can determine the work content associated with the closing of the arm of the shovel 100 based on the operation signal output from the operation signal generating unit of the left control lever 26L. The determination of the work content accompanying the arm closing includes, for example, determination of whether or not the swing-push excavation is performed, whether or not the aerial arm closing swing is performed, whether or not the arm closing is performed alone, and the like. Then, the controller 30 can adjust the flow rate of the hydraulic oil flowing into the direction switching valve 176L by operating the direction switching valve 176L based on the determination result regardless of the operation amount of the left operation lever 26L, as in the case of operating the control valve 177. In the example shown in fig. 9, the controller 30 is configured such that the adjustment amount of the selector valve 176L is the same as the adjustment amount of the control valve 177 in the hydraulic system shown in fig. 3.

With this configuration, the hydraulic system shown in fig. 9 can achieve the same effects as those of the hydraulic system shown in fig. 3.

Next, another configuration example of the shovel 100 according to the embodiment of the present invention will be described with reference to fig. 10. In the example shown in fig. 10, the shovel 100 includes: a1 st hydraulic pump PM1 provided on the upper slewing body; the 1 st actuator ACT 1; the 2 nd actuator ACT 2; a1 st direction change valve DV1 corresponding to the 1 st actuator ACT 1; a2 nd direction change valve DV2 corresponding to the 2 nd actuator ACT 2; a1 st line HP1 connecting the 1 st hydraulic pump PM1 with the 1 st reversing valve DV 1; a line 2 HP2 connecting line 1 HP1 with a direction 2 valve DV 2; a control valve VL disposed in line 2 HP 2; and a control device CTR for controlling the opening area of the control valve VL on the basis of information relating to the operation content.

The 1 st hydraulic pump PM1 is, for example, the left main pump 14L or the right main pump 14R. The 1 st actuator ACT1 is, for example, one of the turning hydraulic motor 2A, the traveling hydraulic motor 2M, the boom cylinder 7, the arm cylinder 8, and the bucket cylinder 9, and the 2 nd actuator ACT2 is the other of the turning hydraulic motor 2A, the traveling hydraulic motor 2M, the boom cylinder 7, the arm cylinder 8, and the bucket cylinder 9.

With this configuration, the shovel 100 can stabilize the operation during the combined operation. This is because, for example, when the shovel 100 performs a combined operation including the operation of the 1 st actuator ACT1 and the operation of the 2 nd actuator ACT2, the flow rate of the working oil flowing into the 1 st actuator ACT1 can be adjusted by adjusting the flow rate of the working oil flowing into the 2 nd actuator ACT 2. Specifically, for example, when the 1 st actuator ACT1 is the turning hydraulic motor 2A and the 2 nd actuator ACT2 is the arm cylinder 8, the excavator 100 can stabilize the operation of the excavator 100 when performing a combined operation including turning operations such as turning-push excavation and aerial arm closing turning. This is because the flow rate of the hydraulic oil flowing into the swing hydraulic motor 2A can be adjusted by adjusting the flow rate of the hydraulic oil flowing into the arm cylinder 8.

The present application claims priority based on japanese patent application No. 2019-.

Description of the symbols

1-lower traveling body, 1C-track, 1 CL-left track, 1 CR-right track, 2-swing mechanism, 2A-swing hydraulic motor, 2M-travel hydraulic motor, 2 ML-left travel hydraulic motor, 2 MR-right travel hydraulic motor, 3-upper swing body, 4-boom, 5-arm, 6-bucket, 7-arm cylinder, 8-arm cylinder, 9-bucket cylinder, 10-cockpit, 11-engine, 13-regulator, 14-main pump, 15-pilot pump, 17-control valve unit, 18-restrictor, 19-control pressure sensor, 26-operating device, 26D-travel lever, 26 DL-left travel lever, 26 DR-right travel lever, 26L-left operation lever, 26R-right operation lever, 28-discharge pressure sensor, 29DL, 29DR, 29LA, 29LB, 29RA, 29 RB-operation pressure sensor, 30-controller, 30 a-information acquisition part, 30B-control part, 31-proportional valve, 40-middle bypass pipeline, 42-parallel pipeline, 43-pipeline, 50-electromagnetic valve, 65, 66-electromagnetic valve, 70-space recognition device, 70F-front sensor, 70B-rear sensor, 70L-left side sensor, 70R-right side sensor, 100-excavator, 71-orientation detection device, 72-information input device, 73-positioning device, 171-176-reversing valve, 177-control valve, 178-relief valve, ACT 1-actuator 1, ACT 2-actuator 2, AT-digging attachment, BP1, BP 2-bifurcation point, CD 1-CD 5-line, CTR-control device, D1-display device, D2-voice output device, DV 1-direction 1-change valve, DV 2-direction 2-change valve, HP 1-line 1, HP 2-line 2, JP 1-confluence point, PM 1-hydraulic pump 1, S1-boom angle sensor, S2-arm angle sensor, S3-bucket angle sensor, S4-body inclination sensor, S5-rotation angle speed sensor, VL-control valve.