阅读说明：本技术 清污机的液压抓斗及液压控制系统 (Hydraulic grab bucket of trash remover and hydraulic control system ) 是由 陈佛生 赵沃洲 彭昭辉 吴永刚 于 2020-06-09 设计创作，主要内容包括：本发明公开一种清污机的液压抓斗及液压控制系统,定耙和两个以上分别与定耙铰接的动耙,每个动耙上都设有驱动该动耙开合的液压油缸。液压控制系统,还包括M型电磁换向阀、电接点压力表、单向阀和油泵,以及溢流阀和油箱。本发明的清污机的液压抓斗的设置了两个以上动耙,动耙与动耙之间无刚性连接,而且每个动耙的开合由单独的液压油缸控制,每个动耙闭合的幅度可以根据其实际抓取的垃圾的尺寸来调整,从而避免抓斗各个部分受力不均匀,以至于液压抓斗整体被破坏的情况。(The invention discloses a hydraulic grab bucket of a trash remover and a hydraulic control system. The hydraulic control system also comprises an M-shaped electromagnetic directional valve, an electric contact pressure gauge, a one-way valve, an oil pump, an overflow valve and an oil tank. The hydraulic grab bucket of the trash remover is provided with more than two movable rakes, the movable rakes are not rigidly connected with each other, the opening and closing of each movable rake is controlled by a single hydraulic oil cylinder, and the closing amplitude of each movable rake can be adjusted according to the size of garbage actually grabbed by each movable rake, so that the condition that all parts of the grab bucket are stressed unevenly and the whole hydraulic grab bucket is damaged is avoided.)

1. Hydraulic grab bucket of trash cleaning machine, its characterized in that includes: the device comprises a fixed rake and N movable rakes which are respectively hinged with the fixed rake, wherein each movable rake is provided with a hydraulic oil cylinder for driving the movable rake to open and close, and N is more than or equal to 2.

2. The hydraulic grab bucket of the trash remover as claimed in claim 1, wherein the piston rod end of the hydraulic cylinder is connected with the movable rake through a connecting shaft, and the large cylinder end is connected with the fixed rake through a connecting shaft.

3. The hydraulic control system of the hydraulic grab bucket of the trash remover is characterized by comprising the hydraulic oil cylinder of claim 1 or 2, an M-shaped electromagnetic directional valve, an electric contact pressure gauge, a pressure switch, a one-way valve, an oil pump, an overflow valve and an oil tank;

two ends of the hydraulic oil cylinder are respectively communicated with the port A and the port B of the M-shaped electromagnetic directional valve through fluids;

the P port of the M-shaped electromagnetic directional valve is in fluid communication with the outlet of the one-way valve;

an inlet of the one-way valve is in fluid communication with an outlet of the oil pump;

an inlet of the oil pump is in fluid communication with an oil tank;

the T port of the M-shaped electromagnetic directional valve is communicated with an oil tank;

the inlet of the overflow valve is in fluid communication with the outlet of the one-way valve, and the outlet of the overflow valve is in fluid communication with the oil tank;

the electric contact pressure gauge and the pressure switch are used for detecting and controlling the system pressure, and are arranged to control the valve core of the M-shaped electromagnetic directional valve to return to a middle position and feed a pressure signal back to the overflow valve when the system pressure exceeds a set value;

the overflow valve is used for receiving the pressure signal and releasing pressure.

4. The hydraulic control system of claim 3, wherein a rod end of the hydraulic ram is in fluid communication with port B of the M-type solenoid directional valve and a large cylinder end of the hydraulic ram is in fluid communication with port A of the M-type solenoid directional valve;

when a piston rod of the hydraulic oil cylinder is retracted into the large cylinder, the grab bucket is opened; when a piston rod of the hydraulic oil cylinder extends out of the large cylinder, the grab bucket is closed.

5. The hydraulic control system of claim 3, wherein a rod end of the hydraulic ram is in fluid communication with port A of the M-type solenoid directional valve and a large cylinder end of the hydraulic ram is in fluid communication with port B of the M-type solenoid directional valve;

when a piston rod of the hydraulic oil cylinder extends out of the large cylinder, the grab bucket is closed; when the piston rod of the hydraulic oil cylinder retracts to the large cylinder, the grab bucket is opened.

6. The hydraulic control system of any one of claims 3-5, further comprising an oil suction filter in fluid communication with an inlet of the oil pump and an oil tank, respectively.

7. The hydraulic control system according to any one of claims 3 to 5, further comprising a return oil filter, one end of the return oil filter being in fluid communication with the T port and the overflow valve of the M-shaped electromagnetic directional valve, and the other end of the return oil filter being in fluid communication with a tank.

Technical Field

The invention relates to the field of hydraulic engineering trash removal, in particular to a hydraulic grab bucket of a trash remover and a hydraulic control system.

Background

In the water conservancy and hydropower engineering, various pollutants carried by high-speed water flow are blocked by the trash racks, the types, the shapes and the sizes of the pollutants are different, and after the pollutants are blocked by the trash racks, the accumulation is irregular, and the pollutants at the bottom of the water cannot be seen. The dirt blocked by the trash rack needs to be cleaned by using a trash cleaning machine.

The existing hydraulic grab bucket is generally composed of a set of fixed harrow and a set of movable harrow, two or more sets of hydraulic oil cylinders are arranged on the movable harrow to control the opening and closing of the grab bucket, most of the oil cylinders are arranged on two sides of the movable harrow, and the stress of the middle section of the grab bucket is usually small. The oil cylinder control system for controlling opening and closing adopts a hydraulic synchronization method, when the size and the shape of dirt grabbed by two sides of the grab bucket are different greatly, the condition that the dirt is locally clamped by the grab bucket and other parts are clamped empty can occur, or all parts of the grab bucket are stressed unevenly, so that the whole hydraulic grab bucket is usually damaged.

Disclosure of Invention

The invention aims to provide a hydraulic grab bucket of a trash remover and a hydraulic control system, which can solve one or more of the problems in the prior art.

According to one aspect of the invention, the hydraulic grab bucket of the trash remover comprises a fixed rake and more than two movable rakes which are respectively hinged with the fixed rake, wherein each movable rake is provided with a hydraulic oil cylinder for driving the movable rake to open and close.

The hydraulic grab bucket of the trash remover is provided with the two or more movable rakes, the movable rakes are not rigidly connected with each other, the opening and closing of each movable rake is controlled by the single hydraulic oil cylinder, and the closing amplitude of each movable rake can be adjusted according to the size of garbage actually grabbed by each movable rake, so that the condition that all parts of the grab bucket are unevenly stressed to damage the whole hydraulic grab bucket is avoided. When the grab bucket is closed to grab dirt, when one movable rake is propped by the dirt with larger volume, the movable rake can not be closed any more, but can press the dirt, and the movable rake which is not propped by the dirt can be closed any more. Under the working condition, the hydraulic oil of the hydraulic loop controls the M-shaped electromagnetic directional valve to change positions (to the middle position) and the overflow valve to directly flow the subsequent hydraulic oil back to the oil tank through the electric contact pressure gauge, and the pressure in the hydraulic system behind the M-shaped electromagnetic directional valve does not continuously rise any more, so that the condition that the whole hydraulic grab is damaged is avoided.

In some embodiments, the piston rod end of the hydraulic oil cylinder of the hydraulic grab bucket of the trash remover is connected with the movable rake through a connecting shaft, and the large cylinder end of the hydraulic oil cylinder is connected with the fixed rake through the connecting shaft.

According to another aspect of the invention, a hydraulic control system of a hydraulic grab bucket of a trash remover is provided, which comprises the hydraulic oil cylinder and is characterized by further comprising an M-shaped electromagnetic directional valve, an electric contact pressure gauge, a pressure switch, a one-way valve, an oil pump, an overflow valve and an oil tank;

two ends of the hydraulic oil cylinder are respectively communicated with the port A and the port B of the M-shaped electromagnetic directional valve through fluid;

the P port of the M-shaped electromagnetic directional valve is in fluid communication with the outlet of the one-way valve;

an inlet of the check valve is in fluid communication with an outlet of the oil pump;

an inlet of the oil pump is in fluid communication with the oil tank;

the T port of the M-shaped electromagnetic directional valve is communicated with the oil tank;

two ends of the overflow valve are respectively in fluid communication with a P port and a T port of the M-shaped electromagnetic directional valve;

the electric contact pressure gauge and the pressure switch are used for detecting and controlling the system pressure, and are arranged to control the valve core of the M-shaped electromagnetic directional valve to return to a middle position and feed a pressure signal back to the overflow valve when the system pressure exceeds a set value;

the overflow valve is used for receiving the pressure signal and releasing pressure.

In some embodiments, a piston rod end of a hydraulic oil cylinder of a hydraulic control system of a grab bucket of the trash remover is in fluid communication with a port B of an M-shaped electromagnetic directional valve, and a large cylinder end of the hydraulic oil cylinder is in fluid communication with a port A of the M-shaped electromagnetic directional valve; when a piston rod of the hydraulic oil cylinder is retracted into the large cylinder, the grab bucket is opened; when a piston rod of the hydraulic oil cylinder extends out of the big cylinder, the grab bucket is closed.

In some embodiments, a piston rod end of a hydraulic oil cylinder of a hydraulic control system of a grab bucket of the trash remover is in fluid communication with an A port of an M-shaped electromagnetic directional valve, and a large cylinder end of the hydraulic oil cylinder is in fluid communication with a B port of the M-shaped electromagnetic directional valve; when a piston rod of the hydraulic oil cylinder extends out of the large cylinder, the grab bucket is opened; when the piston rod of the hydraulic oil cylinder retracts to the big cylinder, the grab bucket is closed.

In some embodiments, the hydraulic control system of the grab bucket of the trash remover of the present invention further comprises an oil suction filter in fluid communication with the inlet of the oil pump and the oil tank, respectively.

In some embodiments, the hydraulic control system of the grab bucket of the trash remover further comprises an oil return filter, one end of the oil return filter is in fluid communication with the T port of the M-shaped electromagnetic directional valve and the overflow valve, and the other end of the oil return filter is in fluid communication with the oil tank.

Drawings

Fig. 1 is a schematic structural diagram of a hydraulic grab bucket of a trash remover according to an embodiment of the invention.

Fig. 2 is a structural schematic diagram of an open state of a movable rake of a hydraulic grab bucket of the trash remover according to an embodiment of the present invention.

Fig. 3 is a schematic structural diagram of a state that a rake of a hydraulic grab bucket of the trash remover grabs the dirt according to an embodiment of the present invention.

Fig. 4 is a schematic structural diagram of a hydraulic control system of the trash remover according to an embodiment of the present invention.

Fig. 5 is a schematic structural diagram of the hydraulic control system shown in fig. 4 when the rake of the trash remover is opened.

Fig. 6 is a schematic structural diagram of the hydraulic control system shown in fig. 4 when the rake of the trash remover is closed.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.

Finally, it should also be noted that, in this document, relational terms such as first and second, counterclockwise and clockwise are only used to distinguish one entity or operation from another entity or operation without necessarily requiring or implying any actual such relationship or order between such entities or operations. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The present invention will be described in further detail with reference to the accompanying drawings.

Fig. 1 schematically shows the structure of a hydraulic grab of a sewage cleaning machine according to an embodiment of the present invention.

Referring to fig. 1, the hydraulic grab bucket of the trash remover includes a fixed rake 10 and three movable rakes (a first movable rake 21, a second movable rake 22 and a third movable rake 23). The first movable harrow 21, the second movable harrow 22 and the third movable harrow 23 are L-shaped and are respectively articulated on the fixed harrow 10 in sequence, and the free ends of the first movable harrow 21, the second movable harrow 22 and the third movable harrow 23 are downward. The first movable rake 21, the second movable rake 22 and the third movable rake 23 are respectively provided with a hydraulic oil cylinder (a first hydraulic oil cylinder 31, a second hydraulic oil cylinder 32 and a third hydraulic oil cylinder 33) for driving the first movable rake, the second movable rake and the third movable rake to open and close.

The hydraulic grab bucket of the trash remover is provided with at least one movable rake, the opening and closing of each movable rake is controlled by a single hydraulic oil cylinder, and the opening and closing amplitude of each movable rake can be adjusted according to the volume of garbage actually grabbed by each movable rake, so that the condition that all parts of the grab bucket are unevenly stressed to damage the whole hydraulic grab bucket is avoided.

In this embodiment, the piston rod end of the first hydraulic cylinder 31 is connected to the first movable rake 21 through a connecting shaft, and the large cylinder end is connected to the fixed rake 10 through a connecting shaft. The piston rod end of the second hydraulic cylinder 32 is connected with the second movable rake 22 through a connecting shaft, and the large cylinder end is connected with the fixed rake 10 through a connecting shaft. The piston rod end of the third hydraulic oil cylinder 33 is connected with the third movable harrow 23 through a connecting shaft, and the big cylinder end is connected with the fixed harrow 10 through a connecting shaft.

In other embodiments, the piston rod end of the first hydraulic cylinder 31 may be connected to the fixed rake 10 through a connecting shaft, and the cylinder end may be connected to the first movable rake 21 through a connecting shaft. The piston rod end of the second hydraulic cylinder 32 is connected with the fixed rake 10 through a connecting shaft, and the big cylinder end is connected with the second movable rake 22 through a connecting shaft. The piston rod end of the third hydraulic oil cylinder 33 is connected with the fixed rake 10 through a connecting shaft, and the big cylinder end is connected with the third movable rake 23 through a connecting shaft.

In this embodiment, the hydraulic grab bucket of trash cleaning machine has set up three width 0.8 meters and has moved the harrow, and every moves the harrow and does not have rigid connection between the harrow, and the opening and shutting of every moves the harrow and is controlled by solitary hydraulic cylinder moreover, and the closed range of every moves the harrow can be adjusted according to the size of the rubbish that it actually snatched to avoid each partial atress of grab bucket inhomogeneous, so that the whole destroyed condition of hydraulic grab bucket. In other embodiments, the number and width of each rake can be set as desired.

The hydraulic grab also comprises a support, and the support comprises a cross rod 51, a first vertical rod 521 and a second vertical rod 522. One end of the cross rod 51 is connected with the first vertical rod 521, and the other end is connected with the second vertical rod 522; one end of the fixed rake 10 is connected with the first vertical rod 521, and the other end is connected with the second vertical rod 522.

The upper ends of the first vertical bar 521 and the second vertical bar 522 are provided with a first roller 531, and the lower ends are provided with a second roller 532. The first roller 531 includes a first circular truncated cone 5311 and a second circular truncated cone 5312 which rotate coaxially, and the radius of the first circular truncated cone 5311 is greater than that of the second circular truncated cone 5312.

An inclined first supporting rod 541 is arranged at the joint of the first vertical rod 531 and the cross rod 51, and an inclined second supporting rod 542 is arranged at the joint of the second vertical rod 532 and the cross rod 51.

The cross rod 51 is fixedly arranged above the fixed rake 10, the piston rod end of the first hydraulic oil cylinder 31 is connected with the first movable rake 21 through a connecting shaft, and the large cylinder end is connected with the cross rod 51 through a connecting shaft. The piston rod end of the second hydraulic cylinder 32 is connected with the second movable rake 22 through a connecting shaft, and the large cylinder end is connected with the cross rod 51 through a connecting shaft. The piston rod end of the third hydraulic oil cylinder 33 is connected with the third movable harrow 23 through a connecting shaft, and the big cylinder end is connected with the cross rod 51 through a connecting shaft.

The hydraulic pumping station 40 for powering the hydraulic cylinders is arranged on the cross bar 51 of the stand.

Fig. 2 schematically shows a structure of an opened state of a hydraulic grab of a trash remover according to an embodiment of the present invention.

Referring to fig. 2, when the cleaning operation is required, the piston rods of the first hydraulic cylinder 31, the second hydraulic cylinder 32 and the third hydraulic cylinder 33 are retracted into the large cylinder to lift the first movable rake 21, the second movable rake 22 and the third movable rake 23 upwards, the hydraulic grab of the cleaning machine is opened, and the rake teeth of the first movable rake 21, the second movable rake 22, the third movable rake 23 and the fixed rake 10 are all vertically downward. At this time, the winch can be used to put down the water surface for decontamination.

Fig. 3 schematically shows a configuration of a state in which a rake of a hydraulic grab of a trash remover grabs dirt according to an embodiment of the present invention.

When the hydraulic grab bucket grabs dirt, the extending lengths of the piston rods of the first hydraulic oil cylinder 31, the second hydraulic oil cylinder 32 and the third hydraulic oil cylinder 33 can be adjusted according to the volume difference of the dirt clamped between the corresponding first movable rake 21, the corresponding second movable rake 22, the corresponding third movable rake 23 and the corresponding fixed rake 10. Referring to fig. 3, the volume of the filth gripped between the second movable rake 22 and the fixed rake 10 is greater than the volume of the filth gripped between the first movable rake 21 and the fixed rake 10 and is also greater than the volume of the filth gripped between the third movable rake 23 and the fixed rake 10.

Fig. 4 schematically shows the structure of a hydraulic control system of a grab bucket of a trash remover according to one embodiment of the present invention.

Referring to fig. 4, the hydraulic control system of the grab bucket of the trash remover comprises three hydraulic cylinders (a first hydraulic cylinder 31, a second hydraulic cylinder 32 and a third hydraulic cylinder 33), an M-shaped electromagnetic directional valve 901, an electric contact pressure gauge 801, a pressure switch 701 and an oil pump 401, as well as an overflow valve 601, a one-way valve 501, an oil suction filter 101, an oil return filter 201 and an oil tank.

The M-shaped electromagnetic directional valve comprises a left functional position, a middle functional position and a right functional position, and the valve core can enable the loop hydraulic oil to form different on-off modes at different positions.

The first hydraulic oil cylinder 31, the second hydraulic oil cylinder 32 and the third hydraulic oil cylinder 33 respectively drive the first movable harrow 21, the second movable harrow 22 and the third movable harrow 23 to open and close.

The first hydraulic ram 31, the second hydraulic ram 32 and the third hydraulic ram 33 are connected in parallel. Two ends of the first hydraulic oil cylinder 31, the second hydraulic oil cylinder 32 and the third hydraulic oil cylinder 33 are respectively communicated with a port A and a port B of the M-shaped electromagnetic directional valve 901 in a fluid mode.

In the present embodiment, the piston rod ends of the first hydraulic cylinder 31, the second hydraulic cylinder 32 and the third hydraulic cylinder 33 are in fluid communication with the port B of the M-type electromagnetic directional valve 901, and the large cylinder end of the hydraulic cylinder 30 is in fluid communication with the port a of the M-type electromagnetic directional valve 901. When the piston rods of the first hydraulic oil cylinder 31, the second hydraulic oil cylinder 32 and the third hydraulic oil cylinder 33 are retracted into the large cylinders, the movable harrow corresponding to each hydraulic oil cylinder is opened; when the piston rods of the first hydraulic oil cylinder 31, the second hydraulic oil cylinder 32 and the third hydraulic oil cylinder 33 extend out of the large cylinders, the movable harrow corresponding to each hydraulic oil cylinder is closed.

In other embodiments, the piston rod ends of the first hydraulic cylinder 31, the second hydraulic cylinder 32 and the third hydraulic cylinder 33 may be in fluid communication with the port a of the M-type electromagnetic directional valve 901, and the large cylinder end of the hydraulic cylinder 30 may be in fluid communication with the port B of the M-type electromagnetic directional valve 901. When the piston rods of the first hydraulic oil cylinder 31, the second hydraulic oil cylinder 32 and the third hydraulic oil cylinder 33 are retracted into the large cylinders, the movable harrow corresponding to each hydraulic oil cylinder is closed; when the piston rods of the first hydraulic oil cylinder 31, the second hydraulic oil cylinder 32 and the third hydraulic oil cylinder 33 extend out of the large cylinder, the movable harrow corresponding to each hydraulic oil cylinder is opened.

The P port of the M-type electromagnetic directional valve 901 is in fluid communication with the outlet of the check valve 501, and the inlet of the oil pump 401 is in fluid communication with the oil tank.

The T port of the M-type electromagnetic directional valve 901 is communicated with the oil tank.

The pressure switch 701 is used in cooperation with the electric contact pressure gauge 801, and is used for detecting and controlling the system pressure, and when the system pressure exceeds a set value, the valve element of the M-shaped electromagnetic directional valve 901 is controlled to return to a middle position, and a pressure signal is fed back to the overflow valve 601.

The inlet of the overflow valve 601 is in fluid communication with the outlet of the oil pump 401 via a check valve 501, and the outlet of the overflow valve 601 is in tank fluid communication via a return oil filter 201. The overflow valve 601 receives a pressure signal of the electric contact pressure gauge 801, and hydraulic oil from the oil pump 401 directly flows back to the oil tank through the overflow valve 601 and the return oil filter 201, so that the pressure of the system is relieved.

The inlet of the check valve 501 is in fluid communication with the outlet of the oil pump 401, and the outlet is in fluid communication with the P port of the M-type electromagnetic directional valve 901.

The two ends of the oil suction filter 101 are respectively in fluid communication with the inlet of the oil pump 401 and the oil tank.

One end of the return oil filter 201 is in fluid communication with the T port of the M-shaped electromagnetic directional valve 901 and the overflow valve 601, and the other end is in fluid communication with the oil tank.

Fig. 5 schematically shows the structure of the hydraulic control system shown in fig. 4 when the rake of the trash remover is opened.

Referring to fig. 5, when the rake needs to be opened, the right 2DT of the M-shaped electromagnetic valve directional valve 901 is powered on, and a left station of the M-shaped electromagnetic valve directional valve 901 forms a passage. The motor 301 for driving the oil pump 401 is started, hydraulic oil in the oil tank passes through the oil absorption filter 101, is pressurized by the oil pump 401, passes through the one-way valve 501, enters through the port P of the M-type electromagnetic valve reversing valve 901, flows out through the port B, enters through the hydraulic oil pipe into the piston rod ends of the first hydraulic oil cylinder 31, the second hydraulic oil cylinder 32 and the third hydraulic oil cylinder 33, and pushes the piston rods to retract into the large cylinders. The hydraulic oil at the large cylinder end of the hydraulic cylinder enters through an A port and flows out through a T port of an M-shaped electromagnetic valve reversing valve 901 through a hydraulic pipeline and then returns to the hydraulic oil tank through an oil return filter 21.

The trash remover has two conditions to rake, one is before grabbing the trash and the other is after grabbing the trash and putting down the trash. The rake opening speed is different because the resistance of pipelines where different rakes are located and the viscous force of dirt are different. The grab bucket is of a structure of one cylinder and one movable harrow, and the movable harrow are not rigidly connected, so that each movable harrow is not required to be opened synchronously.

Fig. 6 schematically shows the structure of the hydraulic control system shown in fig. 4 when the rake of the trash remover is closed.

Referring to fig. 6, the opening and closing of the first movable rake 21, the second movable rake 22 and the third movable rake 23 are controlled by hydraulic cylinders which are independent of each other, and each hydraulic cylinder is not provided with a synchronizing element. The pressure of each hydraulic oil cylinder is controlled by the pressure of the whole system, namely, the pressure is adjusted and controlled by an electric contact pressure gauge 801 and an overflow valve 601.

When the grab bucket executes a finger closing command, the left 1DT of the M-shaped electromagnetic valve reversing valve 901 is electrified, and a right station of the M-shaped electromagnetic valve reversing valve 901 forms a passage. The hydraulic oil in the oil tank passes through the oil absorption filter 101, is pressurized by the oil pump 401, then passes through the one-way valve 501, enters through the port P of the M-shaped electromagnetic valve reversing valve 901, flows out through the port A, enters through the hydraulic oil pipe into the large cylinder ends of the first hydraulic oil cylinder 31, the second hydraulic oil cylinder 32 and the third hydraulic oil cylinder 33, and pushes the piston rod to extend outwards from the large cylinder. The hydraulic oil at the piston rod ends of the first hydraulic cylinder 31, the second hydraulic cylinder 32 and the third hydraulic cylinder 33 enters through a port B and flows out through a port T of the M-shaped electromagnetic valve reversing valve 901 through hydraulic pipelines and then returns to a hydraulic oil tank through the return oil filter 21.

In the rake closing (dirt grabbing) process, the flow control elements are not arranged in the pipeline system, and the rake closing process of each hydraulic oil cylinder is not synchronous, so the extension lengths of the hydraulic oil cylinders are different, the extension length of each hydraulic oil cylinder completely depends on the volume of the grabbed dirt, when the dirt grabbed is large, the oil cylinder extends out to be short, and otherwise, the oil cylinder is long. The control mode can adapt to the working condition of uneven dirt size distribution. If one movable rake is propped by the dirt with larger volume, the movable rake can not be closed any more, but can press the dirt, and the movable rake which is not propped by the dirt is closed continuously. Under the working condition, the hydraulic oil in the hydraulic circuit controls the M-type electromagnetic directional valve to change positions (to the middle position) through the electric contact pressure gauge 801 and the overflow valve 601 to directly flow the subsequent hydraulic oil back to the oil tank, and the pressure in the hydraulic system behind the M-type electromagnetic directional valve does not continuously rise any more, as shown in fig. 4.

When the raking and unloading are carried out, the grab bucket executes a finger opening command, 2DT on the right side of the electromagnetic valve reversing valve 901 is electrified, and a passage is formed on the left station (the left side in the figure) of the M-shaped electromagnetic reversing valve. After being pressurized by the oil suction filter 101 and the oil pump 401, the hydraulic oil directly enters the piston rod ends of the first hydraulic oil cylinder 31, the second hydraulic oil cylinder 32 and the third hydraulic oil cylinder 33 through the one-way valve 501, the M-shaped electromagnetic directional valve and the hydraulic oil pipe to push the piston rods to retract into the large cylinders; the hydraulic oil at the large cylinder end of the oil cylinder returns to the hydraulic oil tank through a hydraulic pipeline, the M-shaped electromagnetic directional valve and the return oil filter 201. Because the resistance of the pipeline where the first movable harrow 21, the second movable harrow 22 and the third movable harrow 23 are located and the viscous force of dirt are different, the harrow opening speed is different, and because the movable harrow in the invention is in a structure of 'one cylinder and one movable harrow', all the movable harrow are not rigidly connected, and the harrow opening action of each movable harrow is not required to be synchronous.

The hydraulic grab bucket of the trash remover is provided with more than two movable rakes, the movable rakes are not rigidly connected with each other, the opening and closing of each movable rake is controlled by a single hydraulic oil cylinder, and the closing amplitude of each movable rake can be adjusted according to the size of garbage actually grabbed by each movable rake, so that the condition that all parts of the grab bucket are stressed unevenly and the whole hydraulic grab bucket is damaged is avoided.

The hydraulic grab bucket adopts a segmented structure of one oil cylinder and one movable rake and a non-synchronous control method, and solves the problems that the existing hydraulic grab bucket is high in manufacturing precision requirement, poor in dirt adapting capability, complex in control system, poor in synchronous effect and dirt cleaning effect and easy to damage the whole hydraulic grab bucket.

The above are only some embodiments of the present invention, and do not limit the concept of the present invention. It will be apparent to those skilled in the art that various changes and modifications can be made without departing from the inventive concept thereof, and these changes and modifications can be made without departing from the spirit and scope of the invention.