阅读说明：本技术 快换装置控制阀组、液压系统和挖掘机 (Quick change device control valve group, hydraulic system and excavator ) 是由 李文举 梅广红 宫永辉 杨正维 张磊 于 2021-10-12 设计创作，主要内容包括：本发明公开了一种快换装置控制阀组、液压系统和挖掘机,快换装置控制阀组包括阀体、主换向阀、第一压力传感器和可调式减压阀,主换向阀的一侧设有与阀组进油口相连的换向阀进油口以及与阀组回油口相连的换向阀回油口,另一侧设有与无杆腔连接油口相连的第一换向工作油口和与所述有杆腔连接油口相连的第二换向工作油口；第一压力传感器用于检测无杆腔连接油口的工作油压；可调式减压阀设在阀组进油口与换向阀进油口之间的进油口连接油路中且减压阀出油口的压力能够调节。其中,快换装置的液压油缸的压力可以根据属具的不同实现手动或自动匹配,快换装置的液压油缸的压力能够随着负载增加而实现补压功能,同时具备减压和溢流双功能。(The invention discloses a quick-change device control valve group, a hydraulic system and an excavator, wherein the quick-change device control valve group comprises a valve body, a main reversing valve, a first pressure sensor and an adjustable pressure reducing valve, one side of the main reversing valve is provided with a reversing valve oil inlet connected with a valve group oil inlet and a reversing valve oil return port connected with a valve group oil return port, and the other side of the main reversing valve is provided with a first reversing working oil port connected with a rodless cavity connecting oil port and a second reversing working oil port connected with a rod cavity connecting oil port; the first pressure sensor is used for detecting the working oil pressure of the rodless cavity connecting oil port; the adjustable pressure reducing valve is arranged in an oil inlet connecting oil way between the valve bank oil inlet and the reversing valve oil inlet, and the pressure of the pressure reducing valve oil outlet can be adjusted. The pressure of the hydraulic oil cylinder of the quick-change device can be matched manually or automatically according to different accessories, the pressure of the hydraulic oil cylinder of the quick-change device can realize a pressure supplementing function along with the increase of the load, and the hydraulic oil cylinder of the quick-change device has the double functions of pressure reduction and overflow.)

1. A quick-change device valve group, characterized in that the quick-change device valve group (1) comprises:

the valve body (1-1) is provided with a valve group oil inlet (P), a valve group oil return port (T) and a rod cavity connecting oil port (B) and a rodless cavity connecting oil port (A) which are respectively externally connected to a rod cavity and a rodless cavity of a hydraulic oil cylinder (6) of the quick change device;

a main reversing valve (1-3), wherein one side of the main reversing valve (1-3) is provided with a reversing valve oil inlet (P1) connected with the valve group oil inlet (P) and a reversing valve oil return port (T1) connected with the valve group oil return port (T), and the other side is provided with a first reversing working oil port (A1) connected with the rodless cavity connecting oil port (A) and a second reversing working oil port (B1) connected with the rod cavity connecting oil port (B);

the first pressure sensor (1-5) is used for detecting the working oil pressure of the rodless cavity connecting oil port (A); and

the adjustable pressure reducing valve is arranged in an oil inlet connecting oil path between the valve bank oil inlet (P) and the reversing valve oil inlet (P1), and the pressure of an oil outlet of the pressure reducing valve can be adjusted.

2. A quick-change device valve group according to claim 1, characterized in that the quick-change device valve group (1) further comprises a controller (5), the controller (5) being electrically connected to the first pressure sensor (1-5) and to the pressure reducing valve and being configured to:

and recording a plurality of corresponding maximum working oil pressure detection values of the hydraulic oil cylinder (6) during different clamping working periods by utilizing the first pressure sensor (1-5) when the quick-change device is matched with different accessories (7).

3. The group of quick-change device control valves according to claim 2, characterized in that the controller (5) is further configured to:

aiming at the type of the accessory (7) matched with the quick-change device, acquiring the maximum working oil pressure detection value correspondingly matched with the accessory (7);

and controlling and adjusting the pressure of an oil outlet of the adjustable pressure reducing valve according to the acquired maximum working oil pressure detection value.

4. The quick-change device control valve group according to claim 3, wherein the pressure of the pressure reducing valve oil outlet is not less than 1.5 times of the corresponding maximum working oil pressure detection value.

5. The quick-change device control valve group according to any one of claims 2 to 4, characterized in that the quick-change device control valve group (1) further comprises an adjustable overflow valve, and the adjustable overflow valve and the pressure reducing valve are arranged in series in the oil inlet connection oil path.

6. The quick-change device control valve group according to claim 5, characterized in that said adjustable pressure reducing valve is a proportional pressure reducing valve and is integrated with said adjustable overflow valve as a proportional pressure reducing overflow valve (1-4).

7. Quick-change device valve group according to claim 5, characterized in that the quick-change device valve group (1) further comprises a second pressure sensor (1-6) for detecting the oil inlet pressure of the valve group oil inlet (P).

8. The group of quick-change device control valves according to claim 7, characterized in that the controller (5) is further configured to:

and adjusting the overflow pressure of the adjustable overflow valve according to the oil inlet pressure detection value of the second pressure sensor (1-6).

9. The quick-change device control valve group according to any one of claims 2 to 4, characterized in that the main reversing valve (1-3) is a two-position four-way solenoid valve and is electrically connected with the controller (5).

10. A quick-change device valve group according to claim 1, characterized in that the quick-change device valve group (1) further comprises:

and a pilot operated check valve (1-2) which is disposed in an internal connection oil path between the rodless chamber connection oil port (A) and the first reversing hydraulic oil port (A1) and is set to allow pressure oil to flow from the first reversing hydraulic oil port (A1) to the rodless chamber connection oil port (A) and to be cut off in a reverse direction, and a pilot oil path of the pilot operated check valve (1-2) is connected to the rodless chamber connection oil port (B) or the second reversing hydraulic oil port (B1).

11. Hydraulic system of a quick-change device, characterized in that it comprises a quick-change device control valve group (1) according to any of claims 1-10.

12. The hydraulic system of a quick-change device according to claim 11, characterized in that the hydraulic system of the quick-change device comprises a quick-change device and the quick-change device control valve group (1), a rod cavity of the hydraulic oil cylinder (6) of the quick-change device is connected to the rod cavity connection oil port (B) of the valve body (1-1), and a rodless cavity of the hydraulic oil cylinder (6) is connected to the rodless cavity connection oil port (a) of the valve body (1-1).

13. Excavator comprising an accessory hydraulic system, characterized in that it further comprises a hydraulic system arranged in parallel with the accessory hydraulic system and comprising a quick-change device according to claim 11 or 12.

Technical Field

The invention relates to the technical field of hydraulic control of engineering machinery, in particular to an excavator, a hydraulic system of the excavator and a quick-change device control valve group.

Background

The excavator has various operation modes, such as excavation, crushing, hydraulic shears, grab buckets and the like, and the operation modes all use different working device accessories (namely attachments) and are frequently replaced according to different working conditions. Wherein, if adopt artifical dismouting mode, then not only increased intensity of labour, wasted time and energy moreover, work efficiency is extremely low. Therefore, many construction machines such as excavators are equipped with an attachment quick-change device to quickly change attachment of a work implement.

Taking an excavator as an example, a hydraulic system of a common quick-change device can only meet a part of quick-change users with low-pressure requirements, but the oil cylinder pressure requirements of the quick-change device are different under different working conditions and different accessories, and the delivery pressure requirements of the quick-change devices are also different. Therefore, the hydraulic system of the existing quick-change device is simple, and has the defects of inconvenience in pressure value adjustment, low pressure, no pressure compensation function and the like.

Disclosure of Invention

The invention mainly aims to provide a quick-change device control valve group, a hydraulic system and an excavator.

In order to achieve the above object, the present invention provides a quick-change device control valve set, including:

the valve body is provided with a valve group oil inlet, a valve group oil return port and a rod cavity connecting oil port and a rodless cavity connecting oil port which are respectively externally connected to a rod cavity and a rodless cavity of a hydraulic oil cylinder of the quick change device;

a reversing valve oil inlet connected with the valve group oil inlet and a reversing valve oil return port connected with the valve group oil return port are arranged on one side of the main reversing valve, and a first reversing working oil port connected with the rodless cavity connecting oil port and a second reversing working oil port connected with the rod cavity connecting oil port are arranged on the other side of the main reversing valve;

the first pressure sensor is used for detecting the working oil pressure of the rodless cavity connecting oil port; and

and the adjustable pressure reducing valve is arranged in an oil inlet connecting oil path between the valve group oil inlet and the reversing valve oil inlet, and the pressure of an oil outlet of the pressure reducing valve can be adjusted.

In some embodiments, the quick-change device control valve block further comprises a controller electrically connected to the first pressure sensor and the pressure relief valve and configured to:

and recording a plurality of corresponding maximum working oil pressure detection values of the hydraulic oil cylinder during different clamping working periods when the quick-change device is matched and clamped with different accessories by using the first pressure sensor.

In some embodiments, the controller is further configured to:

aiming at the type of the accessory matched with the quick-change device, acquiring the maximum working oil pressure detection value correspondingly matched with the accessory;

and controlling and adjusting the pressure of an oil outlet of the adjustable pressure reducing valve according to the acquired maximum working oil pressure detection value.

In some embodiments, the pressure of the oil outlet of the pressure reducing valve is not less than 1.5 times of the corresponding maximum working oil pressure detection value.

In some embodiments, the quick-change device control valve group further comprises an adjustable overflow valve, and the adjustable overflow valve and the pressure reducing valve are arranged in series in the oil inlet connecting oil path.

In some embodiments, the adjustable pressure relief valve is a proportional pressure relief valve and is integrated with the adjustable relief valve into a proportional pressure relief valve.

In some embodiments, the quick-change device control valve block further comprises a second pressure sensor for detecting an oil inlet pressure of the valve block oil inlet.

In some embodiments, the controller is further configured to:

and adjusting the overflow pressure of the adjustable overflow valve according to the oil inlet oil pressure detection value of the second pressure sensor.

In some embodiments, the main reversing valve is a two-position, four-way solenoid valve and is electrically connected to the controller.

In some embodiments, the quick-change device control valve block further comprises:

and the pilot oil way of the hydraulic control one-way valve is connected to the rod cavity connecting oil port or the second reversing working oil port.

In addition, the invention also provides a hydraulic system of the quick-change device, and the hydraulic system of the quick-change device comprises the quick-change device control valve group.

In some embodiments, the hydraulic system of the quick-change device comprises a quick-change device and the quick-change device control valve group, the rod cavity of the hydraulic oil cylinder of the quick-change device is connected to the rod cavity connection oil port of the valve body, and the rodless cavity of the hydraulic oil cylinder is connected to the rodless cavity connection oil port of the valve body.

In addition, the invention also provides an excavator which comprises an accessory hydraulic system and the hydraulic system of the quick-change device, wherein the hydraulic system of the quick-change device is arranged in parallel with the accessory hydraulic system.

The quick-change device control valve group can be adjusted and matched with different pressure requirements of a hydraulic oil cylinder of a quick-change device through the adjustable pressure reducing valve, so that the quick-change device control valve group can be suitable for different quick-change devices, and the same quick-change device can meet the installation requirements of accessories with different pressure requirements in combination with the detection of the first pressure sensor.

Additional features and advantages of embodiments of the invention will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the embodiments of the invention without limiting the embodiments of the invention. In the drawings:

fig. 1 is a schematic structural diagram of a quick-change device control valve group according to an embodiment of the invention;

fig. 2 is a hydraulic schematic diagram of a hydraulic system of a quick-change device of an excavator according to an embodiment of the invention;

fig. 3 is a schematic structural diagram of a control valve group of a quick-change device according to another embodiment of the invention; and

fig. 4 is a control schematic of the hydraulic system of the quick-change device shown in fig. 2.

The reference numbers illustrate:

1 quick change device control valve group 2 hydraulic oil tank

3 hydraulic pump 4 main valve

5 controller 6 hydraulic oil cylinder

7 accessory

1-1 valve body 1-2 hydraulic control one-way valve

1-3 main reversing valve 1-4 proportion pressure reducing overflow valve

1-5 first pressure sensor 1-6 second pressure sensor

1-7 conventional pressure-reducing overflow valve

P valves oil inlet T valves oil return opening

Rod-free cavity connecting oil port A and rod cavity connecting oil port B

P1 switching-over valve oil inlet T1 switching-over valve oil return opening

A1 first reversing working oil port B1 second reversing working oil port

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.

The quick-change device control valve group and the excavator according to the present invention will be described with reference to the accompanying drawings.

Aiming at various defects of a hydraulic system of a quick-change device in the prior art, the invention discloses a novel control valve group of the quick-change device. In one embodiment shown in fig. 1 and 2, the quick-change device control valve group 1 includes:

the valve body 1-1 is provided with a valve bank oil inlet P, a valve bank oil return port T, a rod cavity connecting oil port B and a rodless cavity connecting oil port A, wherein the rod cavity connecting oil port B and the rodless cavity connecting oil port A are respectively externally connected to a rod cavity and a rodless cavity of a hydraulic oil cylinder 6 of the quick change device;

the hydraulic control system comprises a main reversing valve 1-3, wherein one side of the main reversing valve 1-3 is provided with a reversing valve oil inlet P1 connected with a valve bank oil inlet P and a reversing valve oil return port T1 connected with a valve bank oil return port T, and the other side is provided with a first reversing working oil port A1 connected with a rodless cavity connecting oil port A and a second reversing working oil port B1 connected with a rod cavity connecting oil port B;

the first pressure sensor 1-5 is used for detecting the working oil pressure of the rodless cavity connecting oil port A; and

the adjustable pressure reducing valve is arranged in an oil inlet connecting oil path between the valve bank oil inlet P and the reversing valve oil inlet P1, and the pressure of an oil outlet of the pressure reducing valve can be adjusted.

Referring to fig. 2, the main directional control valves 1-3 are used for switching and controlling the extension or retraction of a piston rod of a hydraulic oil cylinder 6 of the quick-change device, namely, the quick-change device forms a clamping locking state or an unlocking state for an accessory 7. The working oil pressure of a rodless cavity connecting oil port A, namely the oil pressure of a rod cavity oil way of a hydraulic oil cylinder 6 of the quick-change device shown in figure 2, namely the pressure of the hydraulic oil cylinder 6 of the quick-change device in a state of clamping and locking an accessory 7 can be detected in real time through the additionally arranged first pressure sensor 1-5; the oil outlet pressure of the adjustable pressure reducing valve can be correspondingly adjusted to match the corresponding load pressure through the oil cylinder pressure (namely, the load pressure) fed back by the first pressure sensor 1-5. When the load pressure is increased, the pressure supplementing function can be realized through the adjustable pressure reducing valve.

In different embodiments shown in fig. 1 and fig. 3, the adjustable pressure reducing valve is a constant-value output pressure reducing valve with adjustable outlet pressure, and each of the proportional pressure reducing overflow valves 1 to 4 and the conventional pressure reducing overflow valves 1 to 7 includes an adjustable pressure reducing valve and a pressure reducing function thereof, and the pressure at the oil outlet of the pressure reducing valve, for example, the pressure at the port a of the conventional pressure reducing overflow valves 1 to 7, can be adjusted.

It can be seen that, through the quick-change device control valve group of the present invention, the pressure of the hydraulic cylinder 6 of the quick-change device can be manually or automatically matched according to the difference of the accessories 7, taking the embodiment of fig. 3 as an example, after different accessories 7 are replaced, a conventional pressure-reducing overflow valve 1-7 suitable for the accessories 7 can be selected, and the oil pressure of the port a thereof matches with the required pressure of the hydraulic cylinder 6 of the quick-change device, for example, the oil pressure of the port a is 1.5 times of the pressure of the hydraulic cylinder 6 of the quick-change device, and so on. In other words, different conventional pressure reducing and overflowing valves 1-7 can be selected for different accessories 7. Of course, the proportional pressure reducing relief valves 1-4 shown in fig. 1 can be adopted, and when the type of the accessory is known through the controller, the pressure of the pressure outlet of the pressure reducing valve of the proportional pressure reducing relief valves 1-4 can be adjusted and taught in a targeted manner.

Taking an excavator as an example, after the quick-change device control valve group 1 is applied to a hydraulic system of the excavator, the hydraulic pump 3 pumps oil from the hydraulic oil tank 2, one part of system pressure oil pumped out by the hydraulic pump 3 flows to the accessory hydraulic system through the main valve 4, and the other part of the system pressure oil flows to the quick-change device hydraulic system, namely flows to the hydraulic oil cylinder 6 of the quick-change device through the quick-change device control valve group 1. In a hydraulic system of the quick-change device, system pressure oil sequentially flows through a valve bank oil inlet P, a proportional pressure-reducing overflow valve 1-4 and a reversing valve oil inlet P1 of a main reversing valve 1-3.

When the hydraulic oil passes through the left position of the two-position four-way main reversing valve 1-3, the oil inlet P1 of the reversing valve is communicated with the first reversing working oil port A1, system pressure oil is provided to the hydraulic oil cylinder 6 of the quick-change device through the rodless cavity connecting oil port A of the quick-change device control valve group 1, and the piston rod is pushed out, so that the quick-change device is in a clamping and locking state. At the moment, low-pressure oil with a rod cavity of the hydraulic oil cylinder 6 sequentially passes through the rod cavity connecting oil port B, the second reversing working oil port B1, the reversing valve oil return port T1 and the valve group oil return port T and returns to the hydraulic oil tank 2.

When the main reversing valve 1-3 is switched to the right position, the oil inlet P1 of the reversing valve is communicated with the second reversing working oil port B1, and oil is supplied towards the rod cavity of the hydraulic oil cylinder 6 through the rod cavity connecting oil port B of the quick-change device control valve group 1, so that the piston rod retracts, and the quick-change device is in an unlocking state. At the moment, rodless cavity low-pressure oil of the hydraulic oil cylinder 6 sequentially passes through the rodless cavity connecting oil port A, the first reversing working oil port A1, the reversing valve oil return port T1 and the valve group oil return port T and returns to the hydraulic oil tank 2.

The hydraulic control one-way valve 1-2 is used for preventing oil liquid in a rodless cavity of the hydraulic oil cylinder 6 from flowing back so as to lock the oil cylinder, maintain pressure in the rodless cavity and keep the extending position of the piston rod and the clamping and locking state of the quick-change device. Specifically, the pilot check valve 1-2 is disposed in an internal connection oil path between the rodless chamber connection oil port a and the first reversing hydraulic oil port a1 and is set to allow pressure oil to flow from the first reversing hydraulic oil port a1 to the rodless chamber connection oil port a and to be cut off in the reverse direction, and a pilot oil path of the pilot check valve 1-2 is connected to the rod chamber connection oil port B or the second reversing hydraulic oil port B1.

When the hydraulic pump 3 stops pumping oil and the main reversing valve 1-3 is in a left position, rodless cavity pressure oil of the hydraulic oil cylinder 6 cannot reversely pass through the hydraulic control one-way valve 1-2, and low pressure oil of a rod cavity of the hydraulic oil cylinder 6 serving as pilot oil cannot unlock the hydraulic control one-way valve 1-2, so that the one-way valve is reversely conducted. Therefore, the pressure maintaining can be realized, and the quick-change device is always in a clamping and locking state.

Compared with the prior hydraulic system of the quick-change device, the prior hydraulic system of the quick-change device does not have the first pressure sensor 1-5 and the adjustable pressure reducing valve, so that the pressure value of the quick-change device cannot be adjusted, or the adjustment is not convenient enough, or when the oil pressure is low, the pressure supplementing function cannot be realized along with the increase of the load, and the safety risk exists. The invention can realize automatic matching of the pressure of the hydraulic oil cylinder 6 of the quick-change device through the adjustable pressure reducing valve, and realize the pressure supplementing function when the pressure of the oil cylinder increases along with the load.

As an example, with reference to fig. 2, 4, the quick-change device control valve group 1 may comprise a controller 5, the controller 5 being electrically connected to the first pressure sensor 1-5 and the pressure reducing valve and configured to: and recording a plurality of corresponding maximum working oil pressure detection values of the hydraulic oil cylinder 6 during different clamping working periods by utilizing the first pressure sensors 1-5 when the quick-change device is matched and clamped with different accessories 7.

In other words, the controller 5 may have a storage module for recording and storing the respective maximum working oil pressure detection values corresponding to the various types of accessories 7. Specifically, when the main valve 4 in fig. 2 controls the first accessory to normally operate, the main directional control valve 1-3 is switched to the left position, the quick-change device is clamped and locked, and during the operation of the first accessory, the oil pressure of the rodless cavity connecting oil port a, namely the first maximum operating oil pressure detection value corresponding to the first accessory, is continuously monitored through the first pressure sensor 1-5, namely the maximum oil pressure required by the quick-change device in the clamping and locking state is detected for the first accessory. By replacing the first attachment with the second attachment and controlling the operation of the second attachment by the main valve 4, a second maximum hydraulic pressure detection value corresponding to the second attachment can be obtained in the same manner. By analogy, the controller can obtain the maximum working oil pressure value required by the clamping and locking state of the quick-change device when accessories of different types and specifications are corresponding through the first pressure sensor 1-5. Therefore, under different working conditions, according to the type of an accessory controlled by the main valve 4, the pressure of the oil outlet of the pressure reducing valve of the adjustable pressure reducing valve can be correspondingly adjusted manually, or the pressure of the oil outlet of the pressure reducing valve is automatically adjusted by controlling the proportional pressure reducing overflow valves 1-4, or the conventional pressure reducing overflow valves 1-7 matched with the pressure of the oil outlet of the pressure reducing valve are selected.

In the embodiments shown in fig. 2, 4, the controller 5 is further configured to:

aiming at the type of an accessory 7 matched with the quick-change device, acquiring a maximum working oil pressure detection value correspondingly matched with the accessory 7;

and controlling and adjusting the pressure of an oil outlet of a pressure reducing valve of the adjustable pressure reducing valve according to the acquired maximum working oil pressure detection value.

It can be seen that, after the storage module of the controller 5 stores the respective maximum working oil pressure detection values corresponding to the various types of accessories 7, the controller 5 may collect the types of the accessories 7 to be operated, and then perform type matching through the data processing module of the controller 5, so as to automatically obtain the maximum working oil pressure detection value corresponding to the accessories 7. Further, the matched maximum working oil pressure detection value information is fed back to provide reference for pressure adjustment of the oil outlet of the pressure reducing valve of the adjustable pressure reducing valve, and the control signal is sent to the proportional pressure reducing overflow valves 1-4 through a signal sending module of the controller 5, so that the pressure of the oil outlet of the pressure reducing valve of the adjustable pressure reducing valve is correspondingly controlled and adjusted.

It should be noted that, in consideration of valve port pressure loss, pipeline pressure loss and the like, the oil pressure of the oil outlet of the pressure reducing valve of the adjustable pressure reducing valve should be greater than the oil pressure of the rodless cavity connecting port a. In the specific setting, the former is usually a constant multiple of the latter, and for example, in the present embodiment, the pressure of the pressure reducing valve outlet is set to be not less than 1.5 times the corresponding maximum hydraulic oil pressure detection value.

In addition, in the hydraulic system of the conventional quick-change device, once the oil pressure of an oil path is too high, no overflow function exists, and safety risk exists. Therefore, the quick-change device control valve group 1 of the present embodiment may further include an adjustable overflow valve, where the adjustable overflow valve and the adjustable pressure reducing valve are serially connected in the oil inlet connection oil path, that is, serially connected in the connection oil path between the valve group oil inlet P and the reversing valve oil inlet P1 in the quick-change device control valve group 1.

In different embodiments shown in fig. 1 and 3, pressure reducing overflow valves are used, and have double functions of pressure reduction and overflow, that is, the proportional pressure reducing overflow valves 1 to 4 and the conventional pressure reducing overflow valves 1 to 7 are respectively integrated with adjustable overflow valves and adjustable pressure reducing valves. The proportional pressure reducing overflow valve 1-4 can adjust the pressure and the overflow pressure of the oil outlet of the pressure reducing valve according to an electric control signal. In the conventional pressure-reducing overflow valve 1-7 shown in fig. 3, the pressure from the port b to the port a has a pressure-reducing function, the pressure at the oil outlet of the pressure-reducing valve is the pressure at the port a, the pressure from the port b to the port c has an overflow function, and excess oil returns to the oil tank hydraulic pressure 2 through the port c and the valve bank oil return port T.

On the basis that the quick-change device control valve group 1 has an overflow function, the quick-change device control valve group 1 can further comprise a second pressure sensor 1-6 for detecting the oil inlet pressure of an oil inlet P of the valve group. The second pressure sensor 1-6 can conduct the oil inlet pressure of the valve group oil inlet P to the controller 5 in real time to monitor whether the overflow pressure is exceeded. In the embodiments of fig. 2, 4, the controller 5 is further configured to: and adjusting the overflow pressure of the adjustable overflow valve according to the oil inlet oil pressure detection value of the second pressure sensor 1-6. Therefore, the overflow pressure value of the proportional pressure reducing overflow valves 1-4 can be correspondingly adjusted through the detection of the second pressure sensors 1-6, and the opening degree of the pump oil valve port of the hydraulic pump 3 serving as a variable pump can also be adjusted in a feedback mode.

In the embodiment of fig. 1 and 3, the main directional control valve 1-3 is a two-position four-way solenoid valve and is electrically connected to the controller 5. The controller 5 can control the lifting of the hydraulic oil cylinder 6 of the quick-change device and internal valve elements such as the proportional pressure reducing overflow valves 1-4 and the like.

On the basis, the invention also discloses a hydraulic system of the quick-change device, which comprises the quick-change device control valve group 1. As shown in fig. 2, in a specific embodiment, the hydraulic system of the quick-change device comprises the quick-change device and a quick-change device control valve group 1, a rod cavity of a hydraulic oil cylinder 6 of the quick-change device is connected to a rod cavity connecting oil port B of the valve body 1-1, and a rodless cavity of the hydraulic oil cylinder 6 is connected to a rodless cavity connecting oil port a of the valve body 1-1.

Similarly, the invention also protects an excavator, which comprises an accessory hydraulic system and a hydraulic system of the quick-change device, wherein the hydraulic system is arranged in parallel with the accessory hydraulic system.

In summary, the quick-change device control valve group 1 of the present invention can be matched with different quick-change devices, or the same quick-change device can meet the installation requirements of accessories 7 with different pressure requirements, and meet the diversity function requirements of the excavator.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; may be mechanically coupled, may be electrically coupled or may be in communication with each other; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.