CN218760657U - Hydraulic control system and working machine - Google Patents

Abstract

The utility model relates to a hydraulic system technical field provides a hydraulic control system and operation machinery. The hydraulic control system comprises a movable arm oil cylinder, an energy accumulator, an explosion-proof device, a main oil source, an oil tank, an explosion-proof control valve, a damping control valve group and a control oil source. And a rodless cavity of the movable arm oil cylinder is connected with the main oil source or the oil tank through the explosion-proof device. And the energy accumulator is connected with the rodless cavity of the movable arm oil cylinder through the damping control valve group. The control oil source is connected with the explosion-proof device through the explosion-proof control valve. The explosion-proof control valve is used for adjusting the working state of the explosion-proof device. And the damping control valve group is used for controlling the communication state of a rodless cavity of the movable arm oil cylinder and the energy accumulator. Through the structure, the explosion-proof state of the explosion-proof device and the damping state of the movable arm oil cylinder can be flexibly adjusted by adjusting the working states of the explosion-proof control valve and the damping control valve group so as to adapt to different operation working conditions.

Description

Hydraulic control system and working machine

Technical Field

The utility model relates to a hydraulic system technical field especially relates to a guide's control system, hydraulic control system and operation machinery.

Background

The loader is an earthwork construction machine widely used for construction of highways, railways, buildings, hydropower, ports, mines and the like. It is mainly used for shoveling and transporting bulk materials such as soil, sand and stone, lime, coal and the like, and can also carry out light shoveling operation on ores, hard soil and the like. During boom lifting, it is generally necessary to activate a boom explosion prevention function in order to improve safety of the work. In the material transportation process, in order to improve the transportation stability and comfort of the whole vehicle, the boom damping function is usually required to be started. At present, a movable arm hydraulic control system capable of flexibly switching various movable arm damping functions of a movable arm explosion-proof function under different working conditions needs to be provided.

SUMMERY OF THE UTILITY MODEL

The utility model provides a hydraulic control system and operation machinery for a hydraulic control system that can switch each movable arm shock-absorbing function of movable arm explosion-proof function in a flexible way under different work condition is provided.

According to the utility model discloses an aspect provides a hydraulic control system, including movable arm hydro-cylinder, energy storage ware, explosion-proof equipment, main oil source, oil tank, explosion-proof control valve, shock attenuation control valves and control oil source.

And a rodless cavity of the movable arm oil cylinder is connected with the main oil source or the oil tank through the explosion-proof device. And the energy accumulator is connected with the rodless cavity of the movable arm oil cylinder through the damping control valve group. The control oil source is connected with the explosion-proof device through the explosion-proof control valve. The explosion-proof control valve is used for adjusting the working state of the explosion-proof device. And the damping control valve group is used for controlling the communication state of a rodless cavity of the movable arm oil cylinder and the energy accumulator.

According to the utility model provides a pair of hydraulic control system, hydraulic control system includes movable arm state diverter valve. The explosion-proof device comprises a locking one-way valve and an explosion-proof reversing valve.

And a rodless cavity of the movable arm oil cylinder is connected with the movable arm state switching valve through the locking one-way valve. And a rod cavity of the movable arm oil cylinder is connected with the movable arm state switching valve. The boom state switching valve is connected to the main oil source and the oil tank. The boom state switching valve is used for adjusting the working state of the boom cylinder.

And a working oil port of the explosion-proof reversing valve is connected with the locking one-way valve. The explosion-proof control valve is connected with a control oil port of the explosion-proof reversing valve and is used for controlling the explosion-proof reversing valve to adjust the working state of the locking one-way valve.

According to the utility model provides a pair of hydraulic control system, the control oil source includes explosion-proof guide's control oil circuit. The explosion-proof reversing valve comprises an explosion-proof position and an explosion-proof relief position. And the control oil port of the anti-explosion reversing valve comprises a first control oil port and a second control oil port. And a working oil port of the explosion-proof control valve is connected with the explosion-proof pilot control oil way, the oil tank and the second control oil port. The first control oil port is connected with the oil tank. The explosion-proof control valve comprises a communication position and a stop position.

And in the state of the communication position, the explosion-proof pilot control oil way is communicated with the second control oil port, the explosion-proof reversing valve is switched to the explosion-proof release position, and the locking one-way valve is in a reverse flow state.

And in the state of the cut-off position, the explosion-proof pilot control oil way is cut off from the second control oil port, the explosion-proof reversing valve is switched to the explosion-proof position, and the locking one-way valve is in a reverse cut-off state.

According to the utility model provides a pair of hydraulic control system, the shock attenuation switch valve group includes shock attenuation pilot control valve and shock attenuation switching module. The control oil source also comprises a pilot pressure oil path and a pressure relief oil path. The pilot pressure oil path and the pressure relief oil path are connected with an oil port on one side of the damping pilot control valve, and an oil port on the other side of the damping pilot control valve is connected with a control oil port of the damping switching assembly. And the energy accumulator is connected with a rodless cavity of the movable arm oil cylinder through a working oil port of the damping switching assembly. The damping pilot control valve is used for controlling the working state of the damping switching assembly so as to adjust the communication state of the accumulator and the rodless cavity of the boom cylinder.

According to the utility model provides a pair of hydraulic control system, the shock attenuation pilot control valve is two tee bend solenoid directional valves. The damping pilot control valve comprises a damping position and a damping release position. And three working oil ports of the damping pilot control valve are respectively connected with the pressure relief oil path, the pilot pressure oil path and the control oil port of the damping switching assembly.

And in the state of the damping position, the pilot pressure oil way is communicated with the control oil port of the damping switching assembly, so that the rodless cavity of the movable arm oil cylinder is communicated with the energy accumulator.

And in the state of the shock absorption release position, the pressure relief oil circuit is communicated with a control oil port of the shock absorption switching assembly, so that a rodless cavity of the movable arm oil cylinder is cut off from the energy accumulator.

According to the utility model provides a pair of hydraulic control system, explosion-proof control valve includes solenoid electric valve. The hydraulic control system further comprises a control device and a vehicle speed detection device. The control device is electrically connected with the vehicle speed detection device, the electromagnetic control valve and the damping pilot control valve. The control device is used for controlling the working states of the electromagnetic control valve and the damping pilot control valve based on the detection result of the vehicle speed detection device.

According to the utility model provides a pair of hydraulic control system, the shock attenuation switching module is including switching control valve, first intercommunication valve and second intercommunication valve.

Wherein the switching control valve includes a damping communication position and a damping cutoff position. The pilot pressure oil path is connected with a control oil port of the switching control valve through a working oil port of the damping pilot control valve, so that the switching control valve is switched between the damping communication position and the damping stop position.

The first communication valve is connected with the energy accumulator, the rodless cavity of the movable arm oil cylinder and the switching control valve. The first communication valve includes a first communication position and a first stop position. The second communicating valve is connected with the oil tank, a rod cavity of the movable arm oil cylinder and the switching control valve. The second communication valve includes a second communication position and a second shut-off position. And the switching control valve is used for controlling the working positions of the first communicating valve and the second communicating valve.

And under the state of the damping communication position, the first communication valve is switched to the first communication position, the second communication valve is switched to the second communication position, a rodless cavity of the movable arm oil cylinder is communicated with the energy accumulator through the first communication valve, and a rod cavity of the movable arm oil cylinder is communicated with the oil tank through the second communication valve.

In the state of the damping cut-off position, the first communicating valve is switched to the first cut-off position, the second communicating valve is switched to the second cut-off position, a rodless cavity of the movable arm oil cylinder is cut off from the energy accumulator, and a rod cavity of the movable arm oil cylinder is cut off from the oil tank.

According to the utility model provides a pair of hydraulic control system, hydraulic control system still includes the pressure balance control valve. The pressure balance control valve is arranged between the energy accumulator and a rodless cavity of the movable arm oil cylinder. The pressure balance control valve is used for balancing pressure between a rodless cavity of the movable arm oil cylinder and the energy accumulator.

According to the utility model provides a pair of hydraulic control system, the pressure balance control valve is tribit tee bend liquid accuse switching-over valve. The three-position three-way hydraulic control reversing valve comprises an oil supplementing level, an oil draining level and a leakage supplementing stopping level. The three-position three-way hydraulic control reversing valve comprises a third control oil port and a fourth control oil port.

And three working oil ports of the three-position three-way hydraulic control reversing valve are respectively connected with the energy accumulator, the pilot pressure oil way and the oil tank. The third control oil port is connected with the energy accumulator. And the fourth control oil port is connected with a rodless cavity of the movable arm oil cylinder.

And under the condition that the pressure of the third control oil port is equal to the pressure of the fourth control oil port, the three-position three-way hydraulic control reversing valve is switched to the make-and-drain cut-off position, and the energy accumulator, the pilot pressure oil way and the oil tank are all cut off.

And under the condition that the pressure of the third control oil port is smaller than the pressure of the fourth control oil port, the three-position three-way hydraulic control reversing valve is switched to the oil supplementing level, and the pilot pressure oil way is communicated with the energy accumulator.

And under the condition that the pressure of the third control oil port is greater than the pressure of the fourth control oil port, the three-position three-way hydraulic control reversing valve is switched to the oil discharge level, and the energy accumulator is communicated with the oil tank.

According to a second aspect of the present invention, there is provided a work machine comprising a hydraulic control system as described above.

The utility model provides an among the hydraulic control system, the rodless chamber of swing arm hydro-cylinder is connected with main oil source or oil tank through explosion-proof equipment, and the pole chamber of swing arm hydro-cylinder is connected with oil tank or main oil source. In the lifting process of the movable arm, oil output by the main oil source flows into a rodless cavity of the movable arm oil cylinder through the explosion-proof device. Oil in a rod cavity of the movable arm oil cylinder flows back to the oil tank. At this time, the piston rod of the boom cylinder extends out, and the boom is lifted. And the explosion-proof device is in an explosion-proof state. That is, the oil outputted from the main oil source can be inputted into the rodless chamber of the boom cylinder through the explosion prevention device, and the explosion prevention device can lock the oil in the rodless chamber of the boom cylinder. When a rubber tube of a rodless cavity of the movable arm oil cylinder breaks, the anti-explosion device locks oil in the rodless cavity of the movable arm oil cylinder to prevent the movable arm from suddenly dropping or falling, and the anti-explosion function of the movable arm is achieved.

The control oil source is connected with the control oil port of the explosion-proof device through the explosion-proof control valve. Through the operating condition of control explosion-proof control valve, can adjust the connected state between the control hydraulic fluid port of control oil source and explosion-proof device, and then adjust explosion-proof device's operating condition. For example, the explosion-proof control valve includes a communication state and a shut-off state. When the explosion-proof control valve is in a communicated state, the control oil source inputs pressure oil to the control oil port of the explosion-proof device through the explosion-proof control valve so that the explosion-proof device is in an explosion-proof state. When the explosion-proof control valve is in a cut-off state, the control oil source and the control oil port of the explosion-proof device are cut off, so that the explosion-proof device is kept in an explosion-proof state. The damping control valve group is arranged between a rodless cavity of the movable arm oil cylinder and the energy accumulator. And the damping control valve group is used for adjusting the communication state of a rodless cavity of the movable arm oil cylinder and the energy accumulator.

For example, when the boom explosion-proof function needs to be started, the working state of the explosion-proof control valve is adjusted, so that the control oil port of the control oil source and the control oil port of the explosion-proof device are cut off, and the explosion-proof device is in an explosion-proof state.

When the shock absorption function of the movable arm needs to be started, the working states of the explosion-proof control valve and the shock absorption control valve group are adjusted, so that the control oil source is communicated with the control oil port of the explosion-proof device, the explosion-proof device is in the explosion-proof state, and the rodless cavity of the movable arm oil cylinder is communicated with the energy accumulator.

Through the structural arrangement, the control oil source is connected with the explosion-proof device through the explosion-proof control valve. The energy accumulator is connected with a rod cavity of the movable arm oil cylinder through the damping control valve group, and the explosion-proof state of the explosion-proof device and the damping state of the movable arm oil cylinder can be flexibly adjusted by adjusting the working states of the explosion-proof control valve and the damping control valve group so as to adapt to different working conditions.

Further, the present invention provides a working machine including the hydraulic control system as described above, which also has various advantages as described above.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a system schematic diagram of a hydraulic control system provided by the present invention;

FIG. 2 is an enlarged view of a portion of FIG. 1 at A;

reference numerals:

100. a boom cylinder; 200. an accumulator; 300. an explosion-proof device; 301. a locking one-way valve; 302. an explosion-proof reversing valve; 303. an explosion-proof position; 304. an explosion-proof release position; 305. a first control oil port; 306. a second control oil port; 401. a source of main oil; 402. an oil tank; 403. a pilot pressure oil path; 404. an explosion-proof pilot control oil way; 405. a pressure relief oil path; 500. a damping control valve group; 510. a damping pilot control valve; 511. a damping position; 512. a shock absorption release position; 520. switching the control valve; 521. a shock absorption communication position; 522. a shock absorbing stop position; 530. a first communication valve; 531. a first communication position; 532. a first stop position; 540. a second communicating valve; 541. a second communication position; 542. a second cut-off position; 600. a boom state switching valve; 700. an explosion-proof control valve; 800. a pressure balance control valve; 801. oil level is supplemented; 802. draining the oil level; 803. a leak-filling cut-off position; 804. a third control oil port; 805. and a fourth control oil port.

Detailed Description

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings and examples. The following examples are provided to illustrate the invention but are not intended to limit the scope of the invention.

In the description of the embodiments of the present invention, it should be noted that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on orientations or positional relationships shown in the drawings, and are only for convenience of description of the embodiments and for simplicity of description, but do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the embodiments of the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the embodiments of the present invention, it should be noted that, unless explicitly stated or limited otherwise, the terms "connected" and "connected" should be interpreted broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; may be directly connected or indirectly connected through an intermediate. The specific meaning of the above terms in the embodiments of the present invention can be understood in specific cases by those skilled in the art.

In embodiments of the invention, unless expressly stated or limited otherwise, the first feature may be directly on or directly under the second feature or indirectly via intermediate members. Also, a first feature "on," "above," and "over" a second feature may mean that the first feature is directly above or obliquely above the second feature, or that only 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 an embodiment 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, without mutual contradiction, those skilled in the art can combine and combine different embodiments or examples and features of different embodiments or examples described in this specification to make the objects, technical solutions, and advantages of the embodiments of the present invention clearer, and the technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

The following describes a hydraulic control system and a working machine according to an embodiment of the present invention with reference to fig. 1 and 2. It should be understood that the following description is only exemplary of the present invention, and is not intended to limit the present invention in any way.

An embodiment of the first aspect of the present invention provides a hydraulic control system, as shown in fig. 1 and fig. 2, the hydraulic control system includes a movable arm cylinder 100, an energy accumulator 200, an explosion-proof device 300, a main oil source 401, an oil tank 402, an explosion-proof control valve 700, a damping control valve set 500, and a control oil source.

The rodless chamber of the boom cylinder 100 is connected to a main oil source 401 or an oil tank 402 through an explosion-proof device 300. The accumulator 200 is connected to the rodless chamber of the boom cylinder 100 through the damping control valve group 500. The control oil source is connected to the explosion-proof device 300 through the explosion-proof control valve 700. The explosion-proof control valve 700 is used to adjust the operating state of the explosion-proof apparatus 300. The damping control valve group 500 is used to control a communication state of the rodless chamber of the boom cylinder 100 with the accumulator 200.

The utility model provides an among the hydraulic control system, the rodless chamber of movable arm hydro-cylinder 100 is connected with main oil source 401 or oil tank 402 through explosion-proof equipment 300, and movable arm hydro-cylinder 100's pole chamber is connected with oil tank 402 or main oil source 401. During the boom-up process, the oil outputted from the main oil source 401 flows into the rodless chamber of the boom cylinder 100 through the explosion-proof device 300. The oil in the rod chamber of the boom cylinder 100 flows back into the oil tank 402. At this time, the piston rod of the boom cylinder 100 extends, and the boom is lifted. And the explosion-proof apparatus 300 is in an explosion-proof state. That is, the oil outputted from the main oil source 401 can be inputted into the rodless chamber of the boom cylinder 100 through the explosion proof device 300, and the explosion proof device 300 can lock the oil in the rodless chamber of the boom cylinder 100. When the rubber hose of the rodless cavity of the boom cylinder 100 is broken, the explosion-proof device 300 locks the oil in the rodless cavity of the boom cylinder 100 to prevent the boom from suddenly dropping or falling, thereby implementing the boom explosion-proof function.

The control oil source is connected with the control oil port of the explosion-proof device 300 through the explosion-proof control valve 700. By controlling the working state of the explosion-proof control valve 700, the communication state between the control oil source and the control oil port of the explosion-proof device 300 can be adjusted, and the working state of the explosion-proof device 300 can be adjusted. For example, the explosion proof control valve 700 includes a communication state and a blocking state. When the explosion-proof control valve 700 is in the connected state, the control oil source inputs pressure oil to the control oil port of the explosion-proof device 300 through the explosion-proof control valve 700, so that the explosion-proof device 300 is released from the explosion-proof state. When the explosion-proof control valve 700 is in a cut-off state, the control oil source is cut off from the control oil port of the explosion-proof device 300, so that the explosion-proof device 300 is kept in an explosion-proof state. The damping control valve group 500 is disposed between the rodless chamber of the boom cylinder 100 and the accumulator 200. The damping control valve group 500 is used to adjust a communication state of the rodless chamber of the boom cylinder 100 with the accumulator 200.

For example, when it is necessary to activate the boom explosion-proof function, the explosion-proof apparatus 300 is in an explosion-proof state by adjusting the operation state of the explosion-proof control valve 700 such that the control oil port of the explosion-proof apparatus 300 is blocked from the control oil source.

When the boom damping function needs to be started, the control oil source is communicated with the control oil port of the explosion-proof device 300 by adjusting the working states of the explosion-proof control valve 700 and the damping control valve group, the explosion-proof device 300 releases the explosion-proof state, and the rodless cavity of the boom cylinder 100 is communicated with the accumulator 200.

With this structural arrangement, the control oil source is connected to the explosion-proof apparatus 300 through the explosion-proof control valve 700. The accumulator 200 is connected to the rod chamber of the boom cylinder 100 through the damping control valve group 500, and the explosion-proof state of the explosion-proof device 300 and the damping state of the boom cylinder 100 can be flexibly adjusted by adjusting the working states of the explosion-proof control valve 700 and the damping control valve group 500 to adapt to different working conditions.

In an embodiment of the present invention, the hydraulic control system includes a boom state switching valve 600, and the explosion-proof device 300 includes a locking check valve 301 and an explosion-proof directional valve 302.

The rodless chamber of the boom cylinder 100 is connected to the boom state switching valve 600 via the lockup check valve 301. The rod chamber of the boom cylinder 100 is connected to the boom state switching valve 600. The boom state switching valve 600 is connected to the main oil source 401 and the tank 402. The boom state switching valve 600 is used to adjust the operation state of the boom cylinder 100.

The working oil port of the explosion-proof reversing valve 302 is connected with the locking one-way valve 301. The explosion-proof control valve 700 is connected with a control oil port of the explosion-proof reversing valve 302 and is used for controlling the explosion-proof reversing valve 302 to adjust the working state of the locking one-way valve 301.

In one embodiment of the present invention, the control oil source comprises an explosion-proof pilot control oil path 404. The explosion-proof reversing valve 302 includes an explosion-proof position 303 and an explosion-proof relief position 304. The control ports of the explosion-proof reversing valve 302 include a first control port 305 and a second control port 306. The working ports of the explosion-proof control valve 700 are connected to the explosion-proof pilot control oil passage 404, the oil tank 402, and the second control oil port 306. The first control port 305 is connected to the oil tank 402. The explosion-proof control valve 700 includes a communication position and a shut-off position.

In the state of the communication position, the explosion-proof pilot control oil way 404 is communicated with the second control oil port 306, the explosion-proof reversing valve 302 is switched to the explosion-proof release position 304, and the locking one-way valve 301 is in a reverse direction flowable state;

in the cut-off position, the explosion-proof pilot control oil passage 404 and the second control oil port 306 are cut off, the explosion-proof selector valve 302 is switched to the explosion-proof position 303, and the lock-up check valve 301 is in the reverse cut-off state.

As shown in fig. 1, in this embodiment, the hydraulic system includes two boom cylinders 100. An explosion-proof device 300 is provided to each rodless chamber of the boom cylinders 100. The rodless chambers of both boom cylinders 100 may be connected to the accumulator 200 through the damping control valve block 500. The rod chambers of the two boom cylinders 100 communicate with each other and are connected to a tank 402 or a main oil source 401. Wherein the main oil source 401 comprises a hydraulic pump.

Taking the explosion-proof device 300 on the left side in fig. 1 and 2 as an example, the explosion-proof device 300 includes a lock check valve 301 and an explosion-proof reversing valve 302. In this embodiment, the explosion-proof reversing valve 302 is a three-position, four-way, pilot operated reversing valve. The lock check valve 301 includes a valve body and a valve spool. The valve core is slidably mounted in the valve body. The valve core and the valve body jointly form three cavities, and the three cavities are respectively a first cavity positioned between one end part of the valve core and the valve body, a second cavity positioned between the other end part of the valve core and the valve body, and a third cavity positioned in the middle of the valve core. The third cavity is an annular cavity, a spring is arranged in the second cavity, and the second cavity is communicated with the third cavity through a damping hole.

And a first working oil port and a second working oil port of the three-position four-way hydraulic control reversing valve are both connected with the first cavity. And a third working oil port and a fourth working oil port of the three-position four-way hydraulic control reversing valve are respectively connected with the second cavity and the third cavity. The first control oil port 305 of the three-position four-way hydraulic control reversing valve is connected with the oil tank 402, the second control oil port 306 is connected with one side oil port of the explosion-proof control valve 700, and the other side oil port of the explosion-proof control valve 700 is connected with the oil tank 402 or the explosion-proof pilot control oil path 404. The three-position four-way pilot operated directional control valve includes an explosion-proof position 303 and an explosion-proof relief position 304. The explosion-proof release bit 304 may further include a first explosion-proof release bit 304 and a second explosion-proof release bit 304. In this embodiment, the left bit is the explosion-proof bit 303, the middle bit is the first explosion-proof release bit 304, and the right bit is the second explosion-proof release bit 304. In the state of the explosion-proof position 303, a third working oil port and a fourth working oil port of the three-position four-way hydraulic control reversing valve are communicated with each other, and the first working oil port and the second working oil port are cut off. In the state of the first explosion-proof release position 304, a fourth working oil port of the three-position four-way hydraulic control reversing valve is communicated with the first working oil port, the second working oil port and the third working oil port are stopped, and a throttling damper is arranged between the fourth working oil port and the first working oil port. In the state of the second explosion-proof release position 304, a fourth working oil port of the three-position four-way hydraulic control reversing valve is communicated with the first working oil port, and the second working oil port is communicated with the third working oil port. In addition, a safety valve may be disposed in the explosion-proof reversing valve 302. A throttle damper and a check valve may also be provided in parallel at the second control port 306.

The boom state switching valve 600 includes a lift position, a cut-off position, and a drop position. One side of the boom state switching valve 600 is connected to the main oil source 401 and the tank 402, and the other side of the boom state switching valve 600 is connected to the rod chamber and the rod-less chamber of the boom cylinder 100. In the lifting position, oil output by the hydraulic pump enters the rodless chamber of the boom cylinder 100, and the oil in the rod chamber of the boom cylinder 100 flows back to the oil tank 402. In the lowered state, oil of the hydraulic pump enters the rod chamber of the boom cylinder 100, and the oil in the rodless chamber of the boom cylinder 100 flows back to the oil tank 402. In the stop position, the oil tank 402 and the hydraulic pump are stopped in both the rodless chamber and the rod chamber of the boom cylinder 100.

During operation, when a boom is required to be lifted, the boom state switching valve 600 is switched to a lifting position, hydraulic oil output from the main oil source 401 enters the lockup check valve 301 through the boom state switching valve 600, and pushes a spool of the lockup check valve 301 to move, so that the hydraulic oil enters a rodless cavity of the boom cylinder 100 through the lockup check valve 301. The oil in the rod chamber of the boom cylinder 100 flows back into the oil tank 402 through the boom state switching valve 600. The piston rod of the boom cylinder 100 extends, and the boom is lifted. At this time, the lockup check valve 301 is in a one-way blocked state, and the oil in the rodless chamber of the boom cylinder 100 is locked and cannot flow out. Therefore, when the rodless chamber oil pipe of the boom cylinder 100 bursts, the boom cylinder 100 does not drop suddenly.

When it is required to lower the boom, the explosion-proof control valve 700 is switched to a communication state so that the pressure oil in the explosion-proof pilot control oil passage 404 is input into the second control oil port 306 through the explosion-proof control valve 700. Under the action of the pressure oil, the explosion-proof reversing valve 302 is switched to an explosion-proof release position 304. At the same time, the boom state switching valve 600 is switched to the lowering position. At this time, the oil in the rodless chamber of the boom cylinder 100 may reversely flow back into the oil tank 402 through the latching check valve 301. Hydraulic oil output from the main oil source 401 is input into a rod chamber of the boom cylinder 100 through the boom state switching valve 600. The piston rod of the boom cylinder 100 contracts and the boom descends.

In the material transportation process, it is generally necessary to switch the boom state switching valve 600 to the stop position, remove the explosion-proof function, and start the boom damping function. Specifically, when it is necessary to start the boom damping function, both the explosion-proof control valve 700 and the damping control valve group 500 are adjusted to a communication state, so that the oil of the explosion-proof pilot control oil passage 404 drives the explosion-proof reversing valve 302 to switch to the explosion-proof release position 304, and the accumulator 200 communicates with the rod chamber of the boom cylinder 100 to start the boom damping function.

In an embodiment of the present invention, the damping control valve group 500 includes a damping pilot control valve 510 and a damping switching assembly. The control oil source further includes a pilot pressure oil passage 403 and a relief oil passage 405. The pilot pressure oil path 403 and the pressure relief oil path 405 are connected to one side oil port of the damping pilot control valve 510, and the other side oil port of the damping pilot control valve 510 is connected to a control oil port of the damping switching assembly. The accumulator 200 is connected to the rodless chamber of the boom cylinder 100 through a working oil port of the shock absorbing switching assembly. The damping pilot control valve 510 serves to control an operation state of the damping switching assembly to adjust a communication state of the accumulator 200 with the rodless chamber of the boom cylinder 100.

In another embodiment of the present invention, the damping pilot control valve 510 is a two-position three-way electromagnetic directional valve. The damping pilot control valve 510 includes a damping bit 511 and a damping release bit 512. Three working oil ports of the damping pilot control valve 510 are respectively connected with the pressure relief oil path 405, the pilot pressure oil path 403 and the control oil ports of the damping switching assembly.

In the state of the damping position 511, the pilot pressure oil path 403 is communicated with the control oil port of the damping switching assembly, so that the rodless cavity of the boom cylinder 100 is communicated with the accumulator 200;

in the state of the damping release position 512, the pressure relief oil path 405 is communicated with the control oil port of the damping switching assembly to stop the rodless cavity of the boom cylinder 100 from the accumulator 200.

Further, in an embodiment of the present invention, the shock absorbing switching assembly includes a switching control valve 520, a first communicating valve 530 and a second communicating valve 540.

Among them, the switching control valve 520 includes a damping communication position 521 and a damping cutoff position 522. The pilot pressure oil passage 403 is connected to a control oil port of the switching control valve 520 through a working oil port of the damping pilot control valve 510 so that the switching control valve 520 is switched between a damping communication position 521 and a damping cutoff position 522.

The first communication valve 530 is connected to the accumulator 200, the rodless chamber of the boom cylinder 100, and the switching control valve 520. First communication valve 530 includes a first communication position 531 and a first off position 532. The second communication valve 540 is connected to the tank 402, the rod chamber of the boom cylinder 100, and the switching control valve 520. The second communication valve 540 includes a second communication position 541 and a second shut-off position 542. The switching control valve 520 controls the operation positions of the first communicating valve 530 and the second communicating valve 540.

In the state of the shock absorption communication position 521, the first communication valve 530 is switched to the first communication position 531, the second communication valve 540 is switched to the second communication position 541, the rod-less chamber of the boom cylinder 100 is communicated with the accumulator 200 through the first communication valve 530, and the rod-having chamber of the boom cylinder 100 is communicated with the oil tank 402 through the second communication valve 540;

in the state of the shock absorbing stop position 522, the first communication valve 530 is switched to the first stop position 532, the second communication valve 540 is switched to the second stop position 542, the rodless chamber of the boom cylinder 100 is stopped from the accumulator 200, and the rod chamber of the boom cylinder 100 is stopped from the tank 402.

As described with reference to fig. 1, the damping control valve group 500 includes a damping pilot control valve 510 and a damping switching assembly. The damping switching assembly includes a switching control valve 520, a first communication valve 530, and a second communication valve 540. For example, the damping pilot control valve 510 is a two-position three-way solenoid control valve. The switching control valve 520 is a two-position three-way pilot operated directional control valve. The first communicating valve 530 and the second communicating valve 540 are both two-position two-way hydraulic control directional valves.

The state shown in fig. 1 is a state in which the damping pilot control valve 510 is not energized, that is, the damping pilot control valve 510 is in the damping release position 512. At this time, the relief oil passage 405 communicates with one control port of the switching control valve 520. At this time, the switching control valve 520 is at the damping cutoff position 522. In this state, the accumulator 200 is communicated with the one-side control port of the first communication valve 530 and the one-side control port of the second communication valve 540 via the switching control valve 520, so that the first communication valve 530 is switched to the first shut-off position 532 and the second communication valve 540 is switched to the second shut-off position 542. At this time, the rodless chamber of boom cylinder 100 is blocked from accumulator 200, and the rod chamber of boom cylinder 100 is blocked from tank 402.

When the damping pilot control valve 510 is energized, i.e. the damping pilot control valve 510 is in the damping position 511. At this time, the pilot pressure oil passage 403 communicates with one control port of the switching control valve 520. At this time, the switching control valve 520 is switched to the damping communication position 521. In this state, the oil at the one-side control port of the first communication valve 530 and the oil at the one-side control port of the second communication valve 540 are discharged into the oil tank 402 through the switching control valve 520, so that the first communication valve 530 is switched to the first communication position 531 and the second communication valve 540 is at the second communication position 541. At this time, the rodless chamber of the boom cylinder 100 communicates with the accumulator 200, and the rod chamber of the boom cylinder 100 communicates with the tank 402.

In an embodiment of the present invention, the hydraulic control system further comprises a pressure balance control valve 800. The pressure balance control valve 800 is disposed between the accumulator 200 and the rodless chamber of the boom cylinder 100. The pressure balance control valve 800 serves to balance the pressure between the rodless chamber of the boom cylinder 100 and the accumulator 200.

Specifically, in one embodiment of the present invention, the pressure balance control valve 800 is a three-position three-way pilot operated directional control valve. The three-position three-way hydraulic control reversing valve comprises an oil supplementing level 801, an oil draining level 802 and an oil supplementing and draining stop level 803. The three-position three-way hydraulic control reversing valve comprises a third control oil port 804 and a fourth control oil port 805.

Three working oil ports of the three-position three-way hydraulic control reversing valve are respectively connected with the energy accumulator 200, the pilot pressure oil path 403 and the oil tank 402. The third control port 804 is connected to the accumulator 200. The fourth control port 805 is connected to a rodless chamber of the boom cylinder 100.

When the pressure of the third control oil port 804 is equal to the pressure of the fourth control oil port 805, the three-position three-way hydraulic control directional control valve is switched to the filling and draining stop position 803, and the energy accumulator 200, the pilot pressure oil path 403 and the oil tank 402 are all stopped;

under the condition that the pressure of the third control oil port 804 is smaller than that of the fourth control oil port 805, the three-position three-way hydraulic control reversing valve is switched to an oil supplementing position 801, and the pilot pressure oil way 403 is communicated with the energy accumulator 200;

under the condition that the pressure of the third control oil port 804 is greater than the pressure of the fourth control oil port 805, the three-position three-way hydraulic control reversing valve is switched to the oil drainage position 802, and the energy accumulator 200 is communicated with the oil tank 402.

With this configuration, when the pressure of the rodless chamber of the boom cylinder 100 is lower than the pressure of the accumulator 200, the accumulator 200 is depressurized to the tank 402 through the pressure balance valve until the pressure of the accumulator 200 is equal to the pressure of the rodless chamber of the boom cylinder 100. When the rodless chamber pressure of the boom cylinder 100 is higher than the pressure of the accumulator 200, the oil in the pilot pressure oil line 403 can be supplemented into the accumulator 200 until the pressure of the accumulator 200 is equal to the rodless chamber pressure of the boom cylinder 100. Therefore, the starting stability and safety of the boom damping function can be improved.

In one embodiment of the present invention, the explosion-proof control valve 700 includes a solenoid control valve. The hydraulic control system further comprises a control device and a vehicle speed detection device. The control device is electrically connected with the vehicle speed detection device, the electromagnetic control valve and the damping pilot control valve 510. The control means is for controlling the operating states of the electromagnetic control valve and the damping pilot control valve 510 based on the detection result of the vehicle speed detection means.

For example, a boom damping start threshold speed value is preset in the control device. The vehicle speed detection device can detect an actual traveling speed of the work machine.

When the actual running speed is greater than or equal to the boom damping starting critical speed, the control device controls the electromagnetic control valve to be electrified so as to switch the electromagnetic control valve to a pressure communication state, namely, the explosion-proof pilot control oil path 404 is communicated with the second control oil port 306 of the explosion-proof reversing valve 302 through the electromagnetic control valve, the explosion-proof reversing valve 302 is switched to the explosion-proof release position 304, and the explosion-proof function is released. Meanwhile, the control device controls the damping pilot control valve 510 to be energized to be switched to the damping position 511, and thus the accumulator 200 is communicated with the rodless chamber of the boom cylinder 100, and the boom damping function is started.

When the actual running speed is lower than the boom damping starting critical speed, the control device controls the electromagnetic control valve not to be electrified so as to switch the electromagnetic control valve to a communication position of the oil tank 402, namely, the oil tank 402 is communicated with the second control oil port 306 of the explosion-proof reversing valve 302 through the electromagnetic control valve, the explosion-proof reversing valve 302 is kept at an explosion-proof position 303, and the explosion-proof function is started. Meanwhile, the control device controls the damping pilot control valve 510 not to be energized to be switched to the damping release position 512, and thus the accumulator 200 is stopped from the rodless chamber of the boom cylinder 100 and the boom damping function is released.

It should be noted that the above embodiment is only an exemplary embodiment of the present invention, and does not limit the present invention in any way. That is, the control device may also adjust the operating states of the solenoid control valve and the damping pilot control valve 510 according to other signals, so as to switch the boom damping function and the explosion-proof function according to different operating conditions. For example, in another embodiment of the present invention, a boom lift height detection device may be provided in the boom cylinder 100. The movable arm lifting height detection device is electrically connected with the control device. The control means can control the operation positions of the electromagnetic control valve and the damping pilot control valve 510 based on the detection result of the boom lift height detecting means.

It should be noted that, in the embodiment of the present invention, the control device may be a conventional hardware control device such as a single chip microcomputer or a PLC. In other words, the control means of the present invention can be implemented by only a hardware device or a hardware circuit without being implemented by a software program.

An embodiment of the second aspect of the present invention provides a working machine, including a hydraulic control system as described above.

For example, the work machine includes a loader. When the boom needs to be lifted when the loader performs a loading operation, the explosion-proof function of the explosion-proof device 300 is activated. When the boom is required to be lowered, the explosion-proof function of the explosion-proof device 300 is released. When the materials need to be transferred, the explosion-proof function of the explosion-proof device 300 is released, and the shock-absorbing function of the boom is started.

It should be understood that the above-described embodiment is only an exemplary embodiment of the present invention, and should not constitute any limitation to the present invention. That is, the above-described work machine includes, but is not limited to, a loader. For example, in another embodiment of the present invention, the work machine may further include an excavator or the like.

Further, the present invention provides a working machine including the hydraulic control system as described above, and therefore, having the advantages as described above.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention in its corresponding aspects.

Claims (10)

1. A hydraulic control system is characterized by comprising a movable arm oil cylinder, an energy accumulator, an explosion-proof device, a main oil source, an oil tank, an explosion-proof control valve, a damping control valve group and a control oil source,

the system comprises a main oil source, an oil tank, an energy accumulator, a damping control valve group, an explosion-proof control valve, a main oil source and an energy storage device, wherein a rodless cavity of the movable arm oil cylinder is connected with the main oil source or the oil tank through the explosion-proof device, the energy storage device is connected with the rodless cavity of the movable arm oil cylinder through the damping control valve group, the control oil source is connected with the explosion-proof device through the explosion-proof control valve, the explosion-proof control valve is used for adjusting the working state of the explosion-proof device, and the damping control valve group is used for controlling the communication state of the rodless cavity of the movable arm oil cylinder and the energy storage device.

2. The hydraulic control system according to claim 1, characterized in that the hydraulic control system includes a boom-state switching valve, the explosion-proof device includes a lockup check valve and an explosion-proof change-over valve,

a rodless cavity of the boom cylinder is connected with the boom state switching valve through the locking one-way valve, a rod cavity of the boom cylinder is connected with the boom state switching valve, the boom state switching valve is connected with the main oil source and the oil tank, the boom state switching valve is used for adjusting the working state of the boom cylinder,

and a working oil port of the explosion-proof reversing valve is connected with the locking one-way valve, and the explosion-proof control valve is connected with a control oil port of the explosion-proof reversing valve and is used for controlling the explosion-proof reversing valve to adjust the working state of the locking one-way valve.

3. The hydraulic control system according to claim 2, wherein the control oil source includes an explosion-proof pilot control oil path, the explosion-proof directional control valve includes an explosion-proof position and an explosion-proof release position, a control oil port of the explosion-proof directional control valve includes a first control oil port and a second control oil port, a working oil port of the explosion-proof control valve is connected with the explosion-proof pilot control oil path, the oil tank and the second control oil port, the first control oil port is connected with the oil tank, the explosion-proof control valve includes a communication position and a stop position,

in the state of the communication position, the explosion-proof pilot control oil way is communicated with the second control oil port, the explosion-proof reversing valve is switched to the explosion-proof release position, and the locking one-way valve is in a reverse flowable state; and in the state of the cut-off position, the explosion-proof pilot control oil way is cut off from the second control oil port, the explosion-proof reversing valve is switched to the explosion-proof position, and the locking one-way valve is in a reverse cut-off state.

4. The hydraulic control system according to claim 3, wherein the damping control valve group includes a damping pilot control valve and a damping switching assembly, the control oil source further includes a pilot pressure oil path and a pressure relief oil path, the pilot pressure oil path and the pressure relief oil path are connected to an oil port on one side of the damping pilot control valve, an oil port on the other side of the damping pilot control valve is connected to a control oil port of the damping switching assembly, the energy accumulator is connected to the rodless cavity of the boom cylinder through an operating oil port of the damping switching assembly, and the damping pilot control valve is configured to control an operating state of the damping switching assembly, so as to adjust a communication state of the energy accumulator with the rodless cavity of the boom cylinder.

5. The hydraulic control system according to claim 4, wherein the damping pilot control valve is a two-position three-way electromagnetic directional valve, the damping pilot control valve comprises a damping position and a damping release position, three working oil ports of the damping pilot control valve are respectively connected with the pressure relief oil path, the pilot pressure oil path and a control oil port of the damping switching assembly,

in the state of the damping position, the pilot pressure oil way is communicated with a control oil port of the damping switching assembly, so that a rodless cavity of the movable arm oil cylinder is communicated with the energy accumulator;

and in the state of the shock absorption release position, the pressure relief oil circuit is communicated with the control oil port of the shock absorption switching assembly, so that the rodless cavity of the movable arm oil cylinder is stopped from the energy accumulator.

6. The hydraulic control system according to claim 5, wherein the explosion-proof control valve includes an electromagnetic control valve, the hydraulic control system further includes a control device and a vehicle speed detection device, the control device is electrically connected to the vehicle speed detection device, the electromagnetic control valve, and the damping pilot control valve, and the control device is configured to control operating states of the electromagnetic control valve and the damping pilot control valve based on a detection result of the vehicle speed detection device.

7. The hydraulic control system of claim 5, wherein the damping switch assembly includes a switch control valve, a first communication valve and a second communication valve,

wherein the switching control valve comprises a damping communication position and a damping cut-off position, the pilot pressure oil path is connected with a control oil port of the switching control valve through a working oil port of the damping pilot control valve so as to switch the switching control valve between the damping communication position and the damping cut-off position,

the first communicating valve is connected with the energy accumulator, the rodless cavity of the movable arm oil cylinder and the switching control valve, the first communicating valve comprises a first communicating position and a first stopping position, the second communicating valve is connected with the oil tank, the rod cavity of the movable arm oil cylinder and the switching control valve, the second communicating valve comprises a second communicating position and a second stopping position, and the switching control valve is used for controlling the working positions of the first communicating valve and the second communicating valve,

in the state of the damping communication position, the first communication valve is switched to the first communication position, the second communication valve is switched to the second communication position, a rodless cavity of the movable arm oil cylinder is communicated with the energy accumulator through the first communication valve, and a rod cavity of the movable arm oil cylinder is communicated with the oil tank through the second communication valve; in the state of the damping cut-off position, the first communicating valve is switched to the first cut-off position, the second communicating valve is switched to the second cut-off position, the rodless cavity of the movable arm oil cylinder is cut off from the energy accumulator, and the rod cavity of the movable arm oil cylinder is cut off from the oil tank.

8. The hydraulic control system of claim 7, further comprising a pressure balance control valve disposed between the accumulator and the rodless chamber of the boom cylinder, the pressure balance control valve to balance pressure between the rodless chamber of the boom cylinder and the accumulator.

9. The hydraulic control system of claim 8, wherein the pressure balancing control valve is a three-position three-way hydraulic control directional control valve, the three-position three-way hydraulic control directional control valve comprises an oil supplementing level, an oil draining level and a leakage supplementing stopping level, the three-position three-way hydraulic control directional control valve comprises a third control oil port and a fourth control oil port,

wherein three working oil ports of the three-position three-way hydraulic control directional control valve are respectively connected with the energy accumulator, the pilot pressure oil path and the oil tank, the third control oil port is connected with the energy accumulator, the fourth control oil port is connected with a rodless cavity of the movable arm oil cylinder,

when the pressure of the third control oil port is equal to the pressure of the fourth control oil port, the three-position three-way hydraulic control reversing valve is switched to the make-and-drain cut-off position, and the energy accumulator, the pilot pressure oil path and the oil tank are cut off; when the pressure of the third control oil port is smaller than the pressure of the fourth control oil port, the three-position three-way hydraulic control reversing valve is switched to the oil supplementing level, and the pilot pressure oil path is communicated with the energy accumulator; and under the condition that the pressure of the third control oil port is greater than the pressure of the fourth control oil port, the three-position three-way hydraulic control reversing valve is switched to the oil discharge level, and the energy accumulator is communicated with the oil tank.

10. A work machine characterized by comprising a hydraulic control system according to any one of claims 1-9.

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