An oil circuit control valve group and a load-sensitive oil cylinder oil circuit control system

Abstract

The utility model discloses an oil way control valve group and load sensitive type oil cylinder oil way control system belong to oil cylinder control technical field, including reversing valve and pressure compensator, and pressure compensator includes shuttle valve and control valve core, and the P mouth of control valve core is used for connecting inlet P, and the P1 mouth of control valve core connects the P mouth of reversing valve, and the A mouth of reversing valve is used for connecting oil cylinder interface A1, and the B mouth of reversing valve is used for connecting oil cylinder interface B1, and the T mouth of reversing valve connects the back oil port T, and the A mouth of shuttle valve is connected between the A mouth of reversing valve and oil cylinder interface A1, and the B mouth of shuttle valve is connected between the B mouth of reversing valve and oil cylinder interface B1, and the C mouth of shuttle valve is connected with the x mouth of control valve core, and the y mouth of control valve core connects the P mouth of reversing valve. Can according to the load condition of oil cylinder, the output pressure of system is adjusted independently, makes the output power maintain in certain range, guarantees the overall system pressure stability, and the versatility is better, has guaranteed the control precision of system.

Description

Technical Field

[0001] This utility model relates to the field of hydraulic cylinder control technology, and in particular to a hydraulic circuit control valve group and a load-sensitive hydraulic cylinder hydraulic circuit control system. Background Technology

[0002] With the upgrading of industrial equipment, the demand for high-precision and high-efficiency equipment is increasing, especially for hydraulic systems, where the design requirements (control accuracy and response efficiency) are also rising. Currently, in the field of hydraulic cylinder control, traditional throttling speed control and servo valve control are still widely used. However, these traditional control methods have limited control strategies, poor adaptability, weak anti-interference capabilities, and difficulty in guaranteeing accuracy. Traditional system parameters are mostly statically set, resulting in fixed control characteristics. During equipment operation, once the operating conditions change, such as load changes, external mechanical shocks and vibrations, or internal pressure fluctuations, the fixed-parameter system cannot make adaptive adjustments, leading to decreased control accuracy and limited versatility. Utility Model Content

[0003] The purpose of this invention is to solve the above-mentioned technical problems and provide an oil circuit control valve group and a load-sensitive oil cylinder oil circuit control system. The pressure compensator can control the pressure entering the P port of the reversing valve according to the pressure change at the load end, and adjust the flow output of the oil supply circuit. The flow adjustment is inversely proportional to the pressure change, thereby adjusting the output pressure and keeping the overall output power within a certain range. This ensures the pressure stability of the oil circuit control system. This invention realizes that the control circuit can autonomously adjust the oil circuit control system according to the load of the oil cylinder, which has better versatility and better control effect, especially for systems with frequent load changes, thus ensuring the control accuracy of the oil circuit control system.

[0004] To achieve the above objectives, this utility model provides the following solution: This utility model discloses an oil circuit control valve assembly, including a directional valve and a pressure compensator. The pressure compensator includes a shuttle valve and a control valve core. The P port of the control valve core is used to connect to the oil inlet P. The P1 port of the control valve core is connected to the P port of the directional valve. The A port of the directional valve is used to connect to the cylinder interface A1. The B port of the directional valve is used to connect to the cylinder interface B1. The T port of the directional valve is connected to the return port T. The A port of the shuttle valve is connected between the A port of the directional valve and the cylinder interface A1. The B port of the shuttle valve is connected between the B port of the directional valve and the cylinder interface B1. The C port of the shuttle valve is connected to the x port of the control valve core. The y port of the control valve core is connected to the P port of the directional valve.

[0005] Preferably, a first on / off valve is connected between port A of the directional valve and port A1 of the cylinder, and port A of the shuttle valve is connected between port A of the directional valve and the first on / off valve; a second on / off valve is connected between port B of the directional valve and port B1 of the cylinder, and port B of the shuttle valve is connected between port B of the directional valve and the second on / off valve.

[0006] Preferably, the first on / off valve is a first hydraulically controlled check valve, and the second on / off valve is a second hydraulically controlled check valve.

[0007] Preferably, it further includes a ball valve, wherein the x port of the first hydraulic check valve and the x port of the second hydraulic check valve are both connected to the A port of the ball valve, the T port of the control valve core, the y port of the first hydraulic check valve and the y port of the second hydraulic check valve are all connected to the control oil port Y1, and the P port of the ball valve is connected to the oil inlet port P.

[0008] Preferably, the ball valve is an electromagnetic ball valve.

[0009] Preferably, the directional valve is a proportional directional valve, with its x port connected to the oil inlet P and its y port connected to the control oil port Y1.

[0010] Preferably, the reversing valve is a three-position four-way reversing valve.

[0011] A load-sensitive hydraulic cylinder circuit control system is also disclosed, including an oil inlet P, an oil return port T, a hydraulic cylinder interface A1, a hydraulic cylinder interface B1, and the aforementioned hydraulic circuit control valve group.

[0012] Preferably, it also includes a control port Y1.

[0013] Preferably, the system further includes a hydraulic cylinder, wherein the rodless chamber of the hydraulic cylinder is connected to the cylinder interface A1, and the rod chamber of the hydraulic cylinder is connected to the cylinder interface B1.

[0014] The present invention achieves the following technical advantages over the prior art: In this invention, the pressure compensator includes a shuttle valve and a control valve core. The shuttle valve senses the oil pressure on the supply and return sides through ports A and B, respectively. The high-pressure side of the control shuttle valve opens, and the oil enters the control valve core through port C as control oil. The control valve core controls the pressure flowing out of port P1 based on the pressure difference between the pressure at port P of the control valve core and port C of the shuttle valve. When the pressure on the supply side increases, the control valve core increases the pressure flowing out of port P1 to reduce the hydraulic oil flow rate at port P1, thereby restoring the pressure at the load end to its pre-pressurization state. When the pressure on the supply side decreases, the control valve core decreases the pressure flowing out of port P1 to increase the hydraulic oil flow rate at port P1, thereby restoring the pressure at the load end to its pre-pressure reduction state. This maintains the overall oil circuit control system pressure stability, ensuring working accuracy. The system can autonomously adjust itself according to the cylinder load, offering better versatility and particularly effective control for systems with frequent load changes, thus guaranteeing the control accuracy of the oil circuit control system. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained by analyzing these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the structure of the load-sensitive hydraulic cylinder oil circuit control system (including the oil circuit control valve group) in an embodiment of this utility model.

[0017] Explanation of reference numerals in the attached diagram: 1. Directional control valve; 2. Shuttle valve; 3. Control valve core; 4. First hydraulically controlled check valve; 5. Second hydraulically controlled check valve; 6. Solenoid ball valve. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments analyzed and obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0019] The purpose of this invention is to provide an oil circuit control valve group and a load-sensitive oil cylinder oil circuit control system to solve the problems existing in the prior art. The pressure compensator can control the pressure entering the P port of the reversing valve according to the pressure change at the load end (oil cylinder interface A1 or oil cylinder interface B1), and adjust the flow rate. The flow rate is inversely proportional to the pressure change, thereby adjusting the output pressure and ensuring the pressure stability of the overall oil circuit control system.

[0020] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0021] Example 1 like Figure 1 As shown, this embodiment provides an oil circuit control valve assembly, including a directional valve 1 and a pressure compensator. The pressure compensator includes a shuttle valve 2 and a control valve core 3. The P port of the control valve core 3 is connected to the oil inlet port P, and the P1 port of the control valve core 3 is connected to the P port of the directional valve 1. The A port of the directional valve 1 is connected to the cylinder interface A1 (the cylinder interface A1 is usually connected to the rodless chamber of the cylinder), the B port of the directional valve 1 is connected to the cylinder interface B1 (the cylinder interface B1 is usually connected to the rod chamber of the cylinder), and the T port of the directional valve 1 is connected to the return port T. The A port of the shuttle valve 2 is connected between the A port of the directional valve 1 and the cylinder interface A1, the B port of the shuttle valve 2 is connected between the B port of the directional valve 1 and the cylinder interface B1, and the C port of the shuttle valve 2 is connected to the x port of the control valve core 3. The y port of the control valve core 3 is connected to the P port of the directional valve 1.

[0022] The shuttle valve 2 senses the oil pressure on both sides through ports A and B respectively, and controls the oil on the high-pressure side to open. The oil enters the x port of the control valve core 3 through port C as control oil. The control valve core 3 controls the pressure flowing out of port P1 of the control valve core 3 according to the pressure difference between the pressure at port P of the control valve core 3 and the pressure at port C of the shuttle valve 2. When the pressure at the load end is high, the control valve core 3 will increase the pressure flowing out of port P1 of the control valve core 3 to reduce the hydraulic oil flow rate at port P1, thereby restoring the pressure at the load end to the level before the pressurization, thus maintaining the pressure stability of the overall oil circuit control system and ensuring working accuracy.

[0023] Taking cylinder interface A1 as the load end and cylinder interface B1 as the return end as an example: When directional valve 1 is switched to the parallel position, ports P and A, and ports B and T of directional valve 1 are connected. Hydraulic oil flows from inlet P through ports P and A of directional valve 1 into cylinder port A1. Return oil flows through cylinder port B1, ports B and T of directional valve 1 into return port T. At this time, the supply pressure is greater than the return pressure, and the pressure on port A of shuttle valve 2 is greater than the pressure on port B. The valve core of shuttle valve 2 is biased to the right. Part of the hydraulic oil in the supply circuit will leak through port C of shuttle valve 2 into port x of control valve core 3. Oil flows out through port y of control valve core 3, the opening of port P1 decreases, the pressure at port P1 increases, and the output flow rate at port P1 decreases (the work done by the hydraulic system = pressure and flow rate; a decrease in flow rate corresponds to an increase in pressure and a corresponding decrease in flow rate) until the valve core of shuttle valve 2 reaches equilibrium. At this time, the position of shuttle valve 2 is set to the initial working position.

[0024] When the load on cylinder port A1 increases, the pressure on port A of shuttle valve 2 increases, causing the valve core of shuttle valve 2 to continue to move to the right. The flow rate of oil discharged from port C of shuttle valve 2 increases, which in turn causes the opening of port P1 to continue to decrease. The pressure at port P1 increases, the flow rate output from port P1 decreases, and the output pressure decreases. This, in turn, reduces the pressure at cylinder port A1 until the valve core of shuttle valve 2 returns to its initial working position, achieving balance. This ensures that the system output power is within a certain range, maintains the overall system pressure stability, and prevents system overload.

[0025] In one embodiment, a first on-off valve (such as a first pilot-operated check valve 4, or other on-off valves) is connected between port A of directional valve 1 and cylinder port A1. Port A of shuttle valve 2 is connected between port A of directional valve 1 and the first on-off valve (such as the first pilot-operated check valve 4). A second on-off valve (such as a second pilot-operated check valve 5, or other on-off valves) is connected between port B of directional valve 1 and cylinder port B1. Port B of shuttle valve 2 is connected between port B of directional valve 1 and the second on-off valve (second pilot-operated check valve 5). By controlling the opening and closing of the first on-off valve (such as the first pilot-operated check valve 4) and the second on-off valve (second pilot-operated check valve 5), the hydraulic cylinder can be locked at a certain position.

[0026] Taking cylinder interface A1 as the load end and cylinder interface B1 as the return end as an example: When the first and second opening / closing valves are in the open state, the oil flows into the cylinder interface A1 only from the oil inlet P, and the oil flows into the return port T from the cylinder interface B1 to complete the return oil.

[0027] When the hydraulic cylinder needs to be locked at a certain position, the first and second opening and closing valves are closed, so no hydraulic oil flows into the rodless chamber of the hydraulic cylinder and no hydraulic oil flows out of the rod chamber, so the piston rod cannot move, thus achieving the locking purpose.

[0028] In one embodiment, the first on / off valve is a first hydraulically controlled check valve 4. The second on / off valve is a second hydraulically controlled check valve 5.

[0029] When the first hydraulic check valve 4 and the second hydraulic check valve 5 are open, they are in a pass state, allowing hydraulic fluid to pass through. When the first hydraulic check valve 4 and the second hydraulic check valve 5 are closed, they are in a one-way state, allowing hydraulic fluid to flow from the inlet P into the cylinder interface A1, and then into the rodless chamber of the hydraulic cylinder. However, the hydraulic oil in the rod chamber of the hydraulic cylinder will not flow from the cylinder interface B1 into the return port T. The pressure in the rodless and rod chambers of the hydraulic cylinder is balanced. Therefore, although the first hydraulic check valve 4 is in a one-way state, hydraulic fluid cannot enter the rodless chamber of the hydraulic cylinder, and the piston rod will not continue to move, achieving the locking purpose.

[0030] In one embodiment, a ball valve 6 is also included. The x-ports of the first hydraulic check valve 4 and the second hydraulic check valve 5 are both connected to the A-port of the ball valve 6. The T-port of the control valve core 3, the y-port of the first hydraulic check valve 4, and the y-port of the second hydraulic check valve 5 are all connected to the control oil port Y1. The P-port of the ball valve 6 is connected to the oil inlet P. The opening and closing states of the first hydraulic check valve 4 and the second hydraulic check valve 5 can be controlled by the ball valve 6.

[0031] The specific process is as follows: When the T port and A port of ball valve 6 are open, the control oil port Y1 supplies oil to the x port and y port of the first hydraulic control check valve 4 and the x port and y port of the second hydraulic control check valve 5. The valve core inside the first hydraulic control check valve 4 and the valve core inside the second hydraulic control check valve 5 remain stationary. The first hydraulic control check valve 4 and the second hydraulic control check valve 5 are closed and are both in a one-way state.

[0032] When the P port and A port of ball valve 6 are connected, the oil inlet P supplies oil to the x port of the first hydraulic check valve 4 and the x port of the second hydraulic check valve 5, and the control oil port Y1 does not supply oil. The y port of the first hydraulic check valve 4 and the y port of the second hydraulic check valve 5 discharge oil to the control oil port Y1. The valve core inside the first hydraulic check valve 4 and the valve core inside the second hydraulic check valve 5 are opened. The first hydraulic check valve 4 and the second hydraulic check valve 5 are open and are both in the pass state.

[0033] In one embodiment, ball valve 6 is an electromagnetic ball valve, which offers a faster response time. When de-energized, ports T and A of ball valve 6 are connected. When energized, ports P and A of ball valve 6 are connected.

[0034] In one embodiment, the directional valve 1 is a proportional directional valve, with its x-port connected to the oil inlet P and its y-port connected to the control oil port Y1. The coordination between the control oil port Y1 and the oil inlet P enables the proportional directional valve to switch directions and regulate the flow rate.

[0035] In one embodiment, the reversing valve 1 is a three-position four-way reversing valve.

[0036] Example 2 like Figure 1 As shown, this embodiment provides a load-sensitive hydraulic cylinder oil circuit control system, including an oil inlet P, an oil return port T, a hydraulic cylinder interface A1, a hydraulic cylinder interface B1, and the oil circuit control valve group in Embodiment 1.

[0037] In one embodiment, a control port Y1 is also included.

[0038] In one embodiment, the system further includes a hydraulic cylinder, with the rodless chamber of the hydraulic cylinder connected to cylinder interface A1 and the rod chamber of the hydraulic cylinder connected to cylinder interface B1. Alternatively, the rodless chamber of the hydraulic cylinder can be connected to cylinder interface B1, and the rod chamber of the hydraulic cylinder can be connected to cylinder interface A1.

[0039] This utility model uses specific examples to illustrate its principles and implementation methods. The above description of the embodiments is only for the purpose of helping to understand the method and core idea of ​​this utility model. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the idea of ​​this utility model. In summary, the content of this specification should not be construed as a limitation of this utility model.

Claims

1. A hydraulic control valve assembly, characterized in that, The device includes a directional control valve and a pressure compensator. The pressure compensator includes a shuttle valve and a control valve core. The P port of the control valve core is connected to the oil inlet port P. The P1 port of the control valve core is connected to the P port of the directional control valve. The A port of the directional control valve is connected to the cylinder interface A1. The B port of the directional control valve is connected to the cylinder interface B1. The T port of the directional control valve is connected to the return port T. The A port of the shuttle valve is connected between the A port of the directional control valve and the cylinder interface A1. The B port of the shuttle valve is connected between the B port of the directional control valve and the cylinder interface B1. The C port of the shuttle valve is connected to the x port of the control valve core. The y port of the control valve core is connected to the P port of the directional control valve.

2. The oil circuit control valve assembly according to claim 1, characterized in that, A first on / off valve is connected between port A of the directional valve and port A1 of the cylinder, and port A of the shuttle valve is connected between port A of the directional valve and the first on / off valve; a second on / off valve is connected between port B of the directional valve and port B1 of the cylinder, and port B of the shuttle valve is connected between port B of the directional valve and the second on / off valve.

3. The oil circuit control valve assembly according to claim 2, characterized in that, The first opening and closing valve is a first hydraulically controlled check valve, and the second opening and closing valve is a second hydraulically controlled check valve.

4. The oil circuit control valve assembly according to claim 3, characterized in that, It also includes a ball valve, wherein the x port of the first hydraulic check valve and the x port of the second hydraulic check valve are both connected to the A port of the ball valve, the T port of the control valve core, the y port of the first hydraulic check valve and the y port of the second hydraulic check valve are all connected to the control oil port Y1, and the P port of the ball valve is connected to the oil inlet port P.

5. The oil circuit control valve assembly according to claim 4, characterized in that, The ball valve is an electromagnetic ball valve.

6. The oil circuit control valve assembly according to claim 1, characterized in that, The directional valve is a proportional directional valve, with its x port connected to the oil inlet P and its y port connected to the control oil port Y1.

7. The oil circuit control valve assembly according to claim 1 or 6, characterized in that, The reversing valve is a three-position four-way reversing valve.

8. A load-sensitive hydraulic cylinder circuit control system, characterized in that, It includes an oil inlet P, an oil return port T, a cylinder interface A1, a cylinder interface B1, and an oil circuit control valve assembly as described in any one of claims 1-7.

9. The load-sensitive hydraulic cylinder circuit control system according to claim 8, characterized in that, It also includes the control port Y1.

10. The load-sensitive hydraulic cylinder circuit control system according to claim 8, characterized in that, It also includes a hydraulic cylinder, wherein the rodless chamber of the hydraulic cylinder is connected to the cylinder interface A1, and the rod chamber of the hydraulic cylinder is connected to the cylinder interface B1.

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