Hydraulic system of a breaking hammer of a construction machine and construction machine

Abstract

The application belongs to the technical field of engineering machinery, and discloses a breaking hammer hydraulic system of engineering machinery and engineering machinery. The breaking hammer hydraulic system of engineering machinery comprises a pump group, a main valve and a reversing valve. The oil inlet of the pump group is communicated with a hydraulic oil tank. The oil outlet of the pump group is connected with the oil inlets of the breaking hammer and the main valve in parallel. The first oil port of the reversing valve is communicated with the first oil inlet and outlet of the main valve. The second oil port of the reversing valve is communicated with the second oil inlet and outlet of the main valve. The oil return port of the reversing valve is communicated with the hydraulic oil tank. The third oil port of the reversing valve is communicated with the rodless cavity of the boom cylinder. The fourth oil port of the reversing valve is communicated with the rod cavity of the boom cylinder. When the reversing valve is in the second working position, the first oil port and the third oil port of the reversing valve are communicated, and the second oil port and the fourth oil port are communicated. When the reversing valve is switched to the first working position, the third oil port and the fourth oil port of the reversing valve are both communicated with the oil return port. The application makes the engineering machinery have two working modes and improves the comfort.

Description

Technical Field

[0001] This invention relates to the field of engineering machinery technology, and in particular to a hydraulic system for a hydraulic breaker and the engineering machinery itself. Background Technology

[0002] Currently, excavator hydraulic breakers are mainly used in mining operations. To prevent dry-firing during breaker operation, the operator first needs to adjust the excavator's posture, then place the breaker's chisel vertically on the rock. Before striking, the operator controls the boom to press the chisel into the breaker, with the front track about 50mm off the ground, and then begins striking. During the breaker's striking process, as the chisel descends, the boom's descent posture must be constantly adjusted to ensure the chisel remains firmly pressed against the rock. This requires a high level of skill from the operator; failure to press firmly against the rock will result in dry-firing. Secondly, during breaker operation, the boom cylinder's hydraulic port is in a sealed state. The two ends of the boom cylinder are connected to the excavator's linkage mechanism, creating a "rigid connection" between the breaker and the excavator body. During breaker operation, the impact force of the rock is transmitted through the breaker, boom, and arm to the excavator's upper and lower frames, cab, and engine, severely impacting the excavator's lifespan and operator comfort. Summary of the Invention

[0003] One object of the present invention is to provide a hydraulic system for a hydraulic breaker of construction machinery, which can improve the service life of construction machinery and improve the comfort of operators.

[0004] To achieve this objective, the present invention adopts the following technical solution:

[0005] The hydraulic system of a hydraulic breaker for construction machinery includes:

[0006] The pump unit has an oil inlet connected to a hydraulic oil tank and an oil outlet connected to a hydraulic breaker.

[0007] The main valve has its inlet connected to the outlet of the pump unit.

[0008] The reversing valve has a first oil port connected to the first inlet / outlet of the main valve, a second oil port connected to the second inlet / outlet of the main valve, a return oil port connected to the hydraulic oil tank, a third oil port connected to the rodless chamber of the boom cylinder, and a fourth oil port connected to the rod chamber of the boom cylinder.

[0009] The directional valve has a first working position and a second working position. When the directional valve is in the first working position, the third oil port and the fourth oil port of the directional valve are both connected to the return oil port of the directional valve. When the directional valve is in the second working position, the first oil port and the third oil port of the directional valve are connected, and the second oil port and the fourth oil port of the directional valve are connected.

[0010] As an optional solution, it also includes a first control valve and a second control valve. The oil inlet of the first control valve is connected to the pump set, the oil return port of the first control valve is connected to the hydraulic oil tank, and the oil outlet of the first control valve is connected to the first control terminal of the directional valve. The oil inlet of the second control valve is connected to the pump set, the oil return port of the second control valve is connected to the hydraulic oil tank, and the oil outlet of the second control valve is connected to the second control terminal of the directional valve.

[0011] As an optional solution, a first check valve is also included. The first check valve is disposed in the oil line between the third oil port of the directional valve and the rodless chamber of the boom cylinder. The first check valve is configured to conduct unidirectionally from the third oil port of the directional valve to the rodless chamber of the boom cylinder. The oil outlet of the first control valve and the oil outlet of the second control valve are both connected to the control oil port of the first check valve. When the first control valve or the second control valve is energized, the first check valve can open.

[0012] As an optional solution, a shuttle valve is also included, wherein the oil outlet of the first control valve is connected to the first oil inlet of the shuttle valve, the oil outlet of the second control valve is connected to the second oil inlet of the shuttle valve, and the oil outlet of the shuttle valve is connected to the control oil port of the first check valve.

[0013] As an optional solution, a confluence valve is also included. The pump set includes a first main pump and a second main pump. The oil outlet of the first main pump is simultaneously connected to the first oil inlet of the confluence valve and the oil inlet of the main valve. The oil outlet of the second main pump is simultaneously connected to the second oil inlet of the confluence valve and the oil inlet of the main valve. The first oil outlet and the second oil outlet of the confluence valve are both connected to the hydraulic breaker.

[0014] As an optional embodiment, the main valve includes a first boom lifting valve, a second boom lifting valve, and a first boom lowering valve. The oil outlet of the first main pump is connected to the oil inlet of the first boom lifting valve and the oil inlet of the first boom lowering valve. The oil outlet of the second main pump is connected to the oil inlet of the second boom lifting valve. The oil outlets of the first boom lifting valve and the second boom lifting valve are both connected to the first oil port of the directional valve. The oil outlet of the first boom lowering valve is connected to the second oil port of the directional valve.

[0015] As an alternative, a connecting oil pipe is provided between the first boom lifting valve and the second boom lifting valve. The connecting oil pipe is equipped with a second check valve, which allows hydraulic oil to flow unidirectionally from the second boom lifting valve to the first boom lifting valve.

[0016] As an optional solution, a first solenoid valve is also included, the oil inlet of which is connected to the oil outlet of the pump unit, and the oil outlet of the first solenoid valve is simultaneously connected to the oil inlets of the first control valve and the second control valve.

[0017] As an optional solution, it also includes a mode selection module, an electric control pedal, and an electric control handle. The mode selection module allows selection between a comfort hammering mode and a standard hammering mode for the construction machinery. When the comfort hammering mode is selected, the electric control pedal controls the hammer to strike while simultaneously energizing the first control valve. When the standard hammering mode is selected, the electric control handle energizes the second control valve, and the electric control pedal only controls the hammer to perform the hammering operation.

[0018] Another objective of this invention is to provide an engineering machinery that improves the service life of the machinery and the driving comfort of the operators.

[0019] To achieve this objective, the present invention adopts the following technical solution:

[0020] The construction machinery adopts the hydraulic system of the hydraulic breaker described in any of the above-mentioned schemes. The construction machinery includes a lower frame, an upper frame, a boom, a boom cylinder, a stick, and a hydraulic breaker. The upper frame is mounted on the lower frame. The boom is hinged to the upper frame via a first pin. The boom cylinder is hinged between the boom and the upper frame. The stick is hinged to the boom. The hydraulic breaker is hinged to the stick.

[0021] The beneficial effects of this invention are:

[0022] This invention provides a hydraulic system for a hydraulic breaker in engineering machinery, comprising a pump unit, a main valve, and a directional valve. The pump unit's inlet is connected to a hydraulic oil tank, and its outlet is connected in parallel with both the hydraulic breaker's and the main valve's inlets. The directional valve's first port is connected to the main valve's first inlet / outlet port, its second port is connected to the main valve's second inlet / outlet port, its return port is connected to the hydraulic oil tank, its third port is connected to the rodless chamber of the boom cylinder, and its fourth port is connected to the rod chamber of the boom cylinder. The directional valve has two working positions: a first working position and a second working position. In the first and second working positions, when the directional valve is in the second working position, the first and third oil ports of the directional valve are connected, and the second and fourth oil ports of the directional valve are connected. At this time, the boom cylinder can lift or lower the boom. When the directional valve is switched to the first working position, the third and fourth oil ports of the directional valve are connected to the return oil port of the directional valve, so that the rodless chamber and the rod chamber of the boom cylinder are connected to the hydraulic oil tank. At this time, when the breaker hammers, the output rod of the boom cylinder can extend and retract freely with the boom, without having to press down the boom to perform the hammering operation. In the hydraulic system of this construction machinery, the directional valve operates the hammer when the hydraulic breaker is in the first working position. The output rod of the boom cylinder is in a free state, and the boom can rotate around the first pivot. The impact vibration of the hammer cannot be transmitted to the excavator's upper frame, protecting the components connected to the upper frame, reducing the failure rate, and improving the comfort of the cab. Moreover, there is no need to continuously press down the boom for hammering; the hammer can break rocks by pressing down under the overall weight of the boom and other components, reducing the labor intensity of the operator. In addition, when the directional valve is switched to the second working position, the boom cylinder can be raised and lowered, making it convenient to use.

[0023] The present invention provides an engineering machinery that, by adopting the hydraulic system of the hydraulic breaker of the engineering machinery, can reduce the failure rate of the engineering machinery, improve the comfort of the cab, and reduce the labor intensity of the operators. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of the engineering machinery provided in the embodiment of the present invention;

[0025] Figure 2 This is a hydraulic schematic diagram of the hydraulic system of the hydraulic breaker for engineering machinery provided in the embodiments of the present invention;

[0026] Figure 3 yes Figure 2 Enlarged view of the structure at point A in the middle;

[0027] Figure 4 yes Figure 2 Enlarged view of the structure at point B.

[0028] In the picture:

[0029] 1. Pump set; 11. First main pump; 12. Second main pump; 13. Pilot pump; 2. Main valve; 21. First boom lifting valve; 211. Connecting oil pipe; 2111. Second check valve; 22. Second boom lifting valve; 23. First boom lowering valve; 3. Directional valve; 4. First control valve; 5. Second control valve; 6. First check valve; 7. Shuttle valve; 8. Merging valve; 81. Merging oil pipe; 9. First switching valve; 10. Second switching valve; 20. First solenoid valve; 30. Second solenoid valve; 40. Third solenoid valve;

[0030] 100. Hydraulic oil tank; 200. Hydraulic breaker; 201. Chisel rod; 300. Boom cylinder; 400. Controller; 500. Electric control pedal; 600. Electric control handle; 700. Lower frame; 800. Upper frame; 900. Boom; 901. First pin; 1000. Stick; 2000. Connecting rod; 3000. First stick cylinder; 4000. Second stick cylinder. Detailed Implementation

[0031] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar components or components having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0032] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection or a detachable connection; a mechanical connection or an electrical connection; a direct connection or an indirect connection through an intermediate medium; or the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0033] In the description of this invention, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0034] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0035] like Figure 1 As shown, the engineering machinery provided in this embodiment of the invention includes a lower frame 700, an upper frame 800, a boom 900, a boom cylinder 300, a stick 1000, a first stick cylinder 3000, a second stick cylinder 4000, a connecting rod 2000, and a breaker hammer 200. The upper frame 800 is rotatably mounted on the lower frame 700. The boom 900 is hinged to the upper frame 800 via a first pin 901. The boom cylinder 300 is hinged to the upper frame 800. Between boom 900 and boom 900, stick 1000 is hinged to the end of boom 900 away from upper frame 800 via a second pin. First stick cylinder 3000 is hinged between boom 900 and stick 1000. Hydraulic breaker 200 is hinged to the end of stick 1000 away from boom 900. One end of connecting rod 2000 is hinged to breaker 200. Second stick cylinder 4000 is hinged to the other end of stick 1000 and connecting rod 2000.

[0036] like Figures 2-4 As shown in the figure, this embodiment of the invention also provides a hydraulic system for a hydraulic breaker of engineering machinery, including a pump set 1, a main valve 2, and a directional valve 3. The inlet of the pump set 1 is connected to the hydraulic oil tank 100, and the outlet of the pump set 1 is connected in parallel with both the hydraulic breaker 200 and the inlet of the main valve 2. The first port of the directional valve 3 is connected to the first inlet and outlet ports of the main valve 2, the second port of the directional valve 3 is connected to the second inlet and outlet ports of the main valve 2, the return port of the directional valve 3 is connected to the hydraulic oil tank 100, the third port of the directional valve 3 is connected to the rodless chamber of the boom cylinder 300, and the fourth port of the directional valve 3 is connected to the rod-side chamber of the boom cylinder 300. The directional valve 3 has two working positions, namely the first... In the first and second working positions, when the directional valve 3 is in the second working position, the first oil port and the third oil port of the directional valve 3 are connected, and the second oil port and the fourth oil port of the directional valve 3 are connected. At this time, the boom cylinder 300 can lift or lower the boom 900. When the directional valve 3 is switched to the first working position, the third oil port and the fourth oil port of the directional valve 3 are both connected to the return oil port of the directional valve 3, so that the rodless chamber and the rod chamber of the boom cylinder 300 are both connected to the hydraulic oil tank 100. At this time, when the breaker 200 is hammering, the output rod of the boom cylinder 300 can freely extend and retract with the boom 900, without having to press down the boom 900 to perform the hammering operation.

[0037] In the first working position, the reversing valve 3 of the hydraulic system of the hydraulic breaker of this construction machinery performs the hammering operation of the hydraulic breaker 200. The output rod of the boom cylinder 300 is in a free state, and the boom 900 can rotate around the first pin 901. According to engineering mechanics analysis, the chisel 201 of the hydraulic breaker 200 is subjected to the upward impact force of the stone, which generates a rotational torque on the first pin 901. The weight of the hydraulic breaker 200 and the stick 1000 and boom 900 connected to it can counteract the rotational torque on the first pin 901. The impact vibration from the hammer cannot be transmitted to the excavator's upper frame 800, protecting the components connected to the upper frame 800, reducing the failure rate, and improving the comfort of the cab. Furthermore, there's no need to constantly press down on the boom 900 for hammering; the breaker 200 can break rocks by pressing down under the overall weight of the boom 900 and the breaker 200, reducing the operator's workload. Additionally, when the reversing valve 3 is switched to the second working position, the boom cylinder 300 can be raised and lowered, making it convenient to use. In this embodiment, the raising and lowering of the boom cylinder 300 can be achieved via the electric control handle 600.

[0038] Pump unit 1 includes a first main pump 11, a second main pump 12, and a pilot pump 13.

[0039] The hydraulic system of the hydraulic breaker in the construction machinery also includes a first control valve 4 and a second control valve 5. The inlet of the first control valve 4 is connected to the outlet of the pilot pump 13, the return port of the first control valve 4 is connected to the hydraulic oil tank 100, and the outlet of the first control valve 4 is connected to the first control terminal of the directional valve 3. When the first control valve 4 is energized and the second control valve 5 is de-energized, the inlet and outlet of the first control valve 4 are connected, allowing the pilot pump 13 to pump hydraulic oil through the first control valve 4 into the first control terminal of the directional valve 3, thus placing the directional valve 3 in its first operating position. When the first control valve 4 is de-energized, the hydraulic oil at the first control terminal flows back to the hydraulic oil tank 100 through the return port of the first control valve 4. The inlet of the second control valve 5 is connected to the outlet of the pilot valve, the return port of the second control valve 5 is connected to the hydraulic oil tank 100, and the outlet of the second control valve 5 is connected to the second control end of the directional valve 3. When the second control valve 5 is energized and the first control valve 4 is de-energized, the inlet of the second control valve 5 and the outlet of the second control valve 5 are connected, and the pilot pump 13 can pump hydraulic oil through the second control valve 5 into the second control end of the directional valve 3 so that the directional valve 3 is in the second working position. When the second control valve 5 is de-energized, the hydraulic oil at the second control end flows back to the hydraulic oil tank 100 through the return port of the second control valve 5.

[0040] The hydraulic system of the hydraulic breaker of this construction machinery also includes a mode selection module, a controller 400, an electric control pedal 500, and an electric control handle 600. The mode selection module, the electric control pedal 500, and the electric control handle 600 are all connected to the controller 400. The construction machinery has a comfortable hammering mode and a standard hammering mode. The mode selection module can be used to select the mode of the construction machinery. When the comfort hammering mode is selected, the electric control pedal 500 controls the breaker hammer 200 to strike while simultaneously energizing the first control valve 4. That is, when the operator presses the electric control pedal 500, the first control valve 4 is simultaneously energized, and the reversing valve 3 switches to the first working position. When the electric control pedal 500 is released, the first control valve 4 is de-energized, and the reversing valve 3 switches to the neutral position. At this time, it does not affect the electric control handle 600's control of the second control valve 5 to raise or lower the boom 900. When the standard hammering mode is selected, the electric control handle 600 can energize the second control valve 5. When it is necessary to raise or lower the boom 900, the electric control handle 600 is moved, and the second control valve 5 is energized. At this time, the electric control pedal 500 can control the breaker hammer 200 to strike, but it cannot energize the first control valve 4.

[0041] The hydraulic system of the hydraulic breaker in the construction machinery also includes a first check valve 6. The first check valve 6 is located in the oil line between the third oil port of the directional valve 3 and the rodless chamber of the boom cylinder 300. The oil outlet of the first control valve 4 and the oil outlet of the second control valve 5 are both connected to the control oil port of the first check valve 6. This allows the hydraulic oil to open the first check valve 6 through the control oil port of the first control valve 4 when either the first control valve 4 or the second control valve 5 is energized, so that the hydraulic oil can flow between the rodless chamber of the boom cylinder 300 and the third oil port of the directional valve 3. This structure enables the first check valve 6 to be opened regardless of whether the directional valve 3 is in the first or second working position. When both the first control valve 4 and the second control valve 5 are de-energized, the first check valve 6 can prevent the hydraulic oil from flowing from the rodless chamber of the boom cylinder 300 to the third oil port of the directional valve 3, so as to prevent leakage from the directional valve 3 and cause the boom 900 to sink.

[0042] Furthermore, the hydraulic system of the hydraulic breaker in the construction machinery also includes a shuttle valve 7. The outlet of the first control valve 4 is connected to the first inlet of the shuttle valve 7, the outlet of the second control valve 5 is connected to the second inlet of the shuttle valve 7, and the outlet of the shuttle valve 7 is connected to the control port of the first check valve 6. This structure controls the opening of the shuttle valve 7 by outputting hydraulic oil through the first control valve 4 and the second control valve 5, thereby realizing the opening of the first check valve 6. The shuttle valve 7 can maintain a constant pressure of output hydraulic oil.

[0043] Continue to refer to Figure 2 and Figure 4The hydraulic system of the hydraulic breaker in the construction machinery also includes a confluence valve 8. The outlet of the first main pump 11 is simultaneously connected to the first inlet of the confluence valve 8 and the inlet of the main valve 2. The outlet of the second main pump 12 is simultaneously connected to the second inlet of the confluence valve 8 and the inlet of the main valve 2. Both the first and second outlets of the confluence valve 8 are connected to the hydraulic breaker 200. This structure allows either the first main pump 11 or the second main pump 12 to control the operation of the hydraulic breaker 200, or both the first main pump 11 and the second main pump 12 to control the operation of the hydraulic breaker 200 simultaneously. When one of the first main pump 11 or the second main pump 12 controls the hydraulic breaker 200, the other can also control the boom cylinder 300 to move, improving the action response speed.

[0044] The first oil outlet and the second oil outlet of the confluence valve 8 are combined through the confluence oil pipe 81 and connected to the breaker hammer 200.

[0045] Specifically, the main valve 2 includes a first boom lifting valve 21, a second boom lifting valve 22, and a first boom lowering valve 23. The boom cylinder 300 includes a first boom cylinder and a second boom cylinder. The outlet of the first main pump 11 is simultaneously connected to the first inlet of the confluence valve 8 and the inlet of the first boom lifting valve 21. The outlet of the second main pump 12 is simultaneously connected to the second inlet of the confluence valve 8 and the inlet of the second boom lifting valve 22. The outlet of the second boom lifting valve 22 is simultaneously connected to the inlet of the first boom lifting valve 21 via a connecting oil pipe 211. The outlet of the boom lifting valve 22 is connected to the first port of the directional control valve 3. When the first boom cylinder and the second boom cylinder are lifted, the first main pump 11 and the second main pump 12 respectively pump hydraulic oil through the first boom lifting valve 21 and the second boom lifting valve 22. The hydraulic oil flowing through the second boom lifting valve 22 then merges with the hydraulic oil flowing into the first boom lifting valve 21 and flows into the first port of the directional control valve 3, and then reaches the rodless chamber of the first boom cylinder and the second boom cylinder (it can be understood that the directional control valve 3 is in the second working position at this time); the outlet of the first boom lowering valve 23 is connected to the first port of the directional control valve 3. The hydraulic oil in the rod chambers of the first and second boom cylinders is connected to the second port of the directional valve 3. During the lifting process, the hydraulic oil flows through the fourth port of the directional valve 3 and the second port of the directional valve 3, through the outlet of the first boom lowering valve 23, and then back to the hydraulic oil tank 100. When the first boom lifting valve 21 and the second boom lifting valve 22 are lowering, the second boom cylinder does not need to participate in the lowering action due to gravity. Only when the first boom lowering valve 23 is energized, the first main pump 11 pumps hydraulic oil through the first boom lowering valve. The oil outlet of valve 23 enters the rod chamber of the first boom cylinder and the second boom cylinder (the rod chambers of the first boom cylinder and the second boom cylinder, as well as the rodless chambers of the first boom cylinder and the second boom cylinder, are interconnected. Therefore, when the first main pump 11 is working, hydraulic oil can flow into the rod chambers of both the first boom cylinder and the second boom cylinder. At this time, the directional valve 3 is still in the second working position). The hydraulic oil in the rodless chambers of the first boom cylinder and the second boom cylinder returns through the oil outlet of the first boom lifting valve 21 and then through the hydraulic oil tank 100, realizing the boom 900 lowering action. A second check valve 2111 is provided on the connecting oil pipe 211. The second check valve 2111 allows the hydraulic oil to flow unidirectionally from the second boom lifting valve 22 to the first boom lifting valve 21.

[0046] The hydraulic system of the hydraulic breaker of the construction machinery also includes a first switching valve 9 and a second switching valve 10. The oil inlet of the first switching valve 9 is connected to the oil return port of the first boom lifting valve 21, and the oil outlet of the first switching valve 9 is connected to the hydraulic oil tank 100. The oil inlet of the second switching valve 10 is connected to the oil return port of the second boom lifting valve 22, and the oil outlet of the second switching valve 10 is connected to the hydraulic oil tank 100. For example, when the first main pump 11 is used to control the operation of the hydraulic breaker 200, the first switching valve 9 is closed to prevent hydraulic oil from being depressurized through the return oil of the first switching valve 9, while the second switching valve 10 is in the open state.

[0047] The hydraulic system of the hydraulic breaker in construction machinery also includes a solenoid valve assembly, which comprises a first solenoid valve 20, a second solenoid valve 30, and a third solenoid valve 40. The inlet of the first solenoid valve 20 is connected to the outlet of the pilot pump 13, and the outlet of the first solenoid valve 20 is connected in parallel with the inlets of the first control valve 4 and the second control valve 5. The first solenoid valve 20 is a safety protection valve; the boom 900 can only be raised or lowered by moving the electric control handle 600 when the first solenoid valve 20 is energized. The inlets of the second solenoid valve 30 and the third solenoid valve 40 are both connected to the outlet of the pilot pump 13. The outlet of the second solenoid valve 30 is connected to the control terminal of the first switching valve 9 to control the on / off state of the first switching valve 9, and the outlet of the third solenoid valve 40 is connected to the control terminal of the second switching valve 10 to control the on / off state of the second switching valve 10.

[0048] This embodiment provides an engineering machinery system that uses a hydraulic breaker. The engineering machinery can operate in either a comfort hammering mode or a standard hammering mode, providing operators with two modes for convenience. When the engineering machinery is used in the comfort hammering mode, the failure rate of the engineering machinery can be reduced, the comfort of the cab can be improved, and the labor intensity of the operator can be reduced. The engineering machinery also has a standard hammering mode, providing operators with more options.

[0049] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A hydraulic system for a hydraulic breaker in construction machinery, characterized in that, include: Pump set (1), the oil inlet of the pump set (1) is connected to the hydraulic oil tank (100), and the oil outlet of the pump set (1) is connected to the breaker hammer (200); The main valve (2) has an oil inlet that is connected to the oil outlet of the pump unit (1); The reversing valve (3) has a first oil port connected to the first inlet and outlet oil ports of the main valve (2), a second oil port connected to the second inlet and outlet oil ports of the main valve (2), a return oil port connected to the hydraulic oil tank (100), a third oil port connected to the rodless chamber of the boom cylinder (300), and a fourth oil port connected to the rod chamber of the boom cylinder (300). The reversing valve (3) has a first working position and a second working position. When the reversing valve (3) is in the first working position, the third oil port and the fourth oil port of the reversing valve (3) are both connected to the return oil port of the reversing valve (3). When the reversing valve (3) is in the second working position, the first oil port and the third oil port of the reversing valve (3) are connected, and the second oil port and the fourth oil port of the reversing valve (3) are connected. The hydraulic system of the hydraulic breaker of the construction machinery also includes a first control valve (4) and a second control valve (5). The oil inlet of the first control valve (4) is connected to the pump group (1), the oil return port of the first control valve (4) is connected to the hydraulic oil tank (100), and the oil outlet of the first control valve (4) is connected to the first control end of the reversing valve (3). The oil inlet of the second control valve (5) is connected to the pump group (1), the oil return port of the second control valve (5) is connected to the hydraulic oil tank (100), and the oil outlet of the second control valve (5) is connected to the second control end of the reversing valve (3).

2. The hydraulic system for a hydraulic breaker of engineering machinery according to claim 1, characterized in that, It also includes a first check valve (6), which is located on the oil line between the third oil port of the directional valve (3) and the rodless chamber of the boom cylinder (300). The first check valve (6) is configured to conduct unidirectionally from the third oil port of the directional valve (3) to the rodless chamber of the boom cylinder (300). The oil outlet of the first control valve (4) and the oil outlet of the second control valve (5) are both connected to the control oil port of the first check valve (6). When the first control valve (4) or the second control valve (5) is energized, the first check valve (6) can be opened.

3. The hydraulic system for a hydraulic breaker of engineering machinery according to claim 2, characterized in that, It also includes a shuttle valve (7), the oil outlet of the first control valve (4) is connected to the first oil inlet of the shuttle valve (7), the oil outlet of the second control valve (5) is connected to the second oil inlet of the shuttle valve (7), and the oil outlet of the shuttle valve (7) is connected to the control oil port of the first check valve (6).

4. The hydraulic system for a hydraulic breaker of engineering machinery according to any one of claims 1-3, characterized in that, It also includes a confluence valve (8). The pump set (1) includes a first main pump (11) and a second main pump (12). The oil outlet of the first main pump (11) is simultaneously connected to the first oil inlet of the confluence valve (8) and the oil inlet of the main valve (2). The oil outlet of the second main pump (12) is simultaneously connected to the second oil inlet of the confluence valve (8) and the oil inlet of the main valve (2). The first oil outlet of the confluence valve (8) and the second oil outlet of the confluence valve (8) are both connected to the hydraulic breaker (200).

5. The hydraulic system for a hydraulic breaker of engineering machinery according to claim 4, characterized in that, The main valve (2) includes a first boom lifting valve (21), a second boom lifting valve (22), and a first boom lowering valve (23). The oil outlet of the first main pump (11) is connected to the oil inlet of the first boom lifting valve (21) and the oil inlet of the first boom lowering valve (23). The oil outlet of the second main pump (12) is connected to the oil inlet of the second boom lifting valve (22). The oil outlets of the first boom lifting valve (21) and the second boom lifting valve (22) are both connected to the first oil port of the directional valve (3). The oil outlet of the first boom lowering valve (23) is connected to the second oil port of the directional valve (3).

6. The hydraulic system for a hydraulic breaker of engineering machinery according to claim 5, characterized in that, A connecting oil pipe (211) is provided between the first boom lifting valve (21) and the second boom lifting valve (22). The connecting oil pipe (211) is provided with a second check valve (2111). The second check valve (2111) enables hydraulic oil to flow unidirectionally from the second boom lifting valve (22) to the first boom lifting valve (21).

7. The hydraulic system for a hydraulic breaker of engineering machinery according to any one of claims 1-3, characterized in that, It also includes a first solenoid valve (20), the oil inlet of the first solenoid valve (20) is connected to the oil outlet of the pump group (1), and the oil outlet of the first solenoid valve (20) is simultaneously connected to the oil inlets of the first control valve (4) and the second control valve (5).

8. The hydraulic system for a hydraulic breaker of engineering machinery according to any one of claims 1-3, characterized in that, It also includes a mode selection module, an electric control pedal (500), and an electric control handle (600). The mode selection module allows the construction machinery to select between a comfortable hammering mode and a standard hammering mode. When the comfortable hammering mode is selected, the electric control pedal (500) controls the first control valve (4) to be energized while controlling the breaker (200) to hammer. When the standard hammering mode is selected, the electric control handle (600) can control the second control valve (5) to be energized. The electric control pedal (500) only controls the breaker (200) to perform hammering operations.

9. Construction machinery, characterized in that, The hydraulic system of the hydraulic breaker of the construction machinery according to any one of claims 1-8, the construction machinery includes a lower frame (700), an upper frame (800), a boom (900), a boom cylinder (300), a stick (1000) and a hydraulic breaker (200), the upper frame (800) is disposed on the lower frame (700), the boom (900) is hinged to the upper frame (800) through a first pin (901), the boom cylinder (300) is hinged between the boom (900) and the upper frame (800), the stick (1000) is hinged to the boom (900), and the hydraulic breaker (200) is hinged to the stick (1000).

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