Hydraulic system capable of achieving high-speed pressure relief

Abstract

The invention belongs to the technical field of engineering machinery, and relates to a hydraulic system capable of realizing high-speed pressure relief, which comprises a hydraulic station unit, an execution unit and a valve group, the valve group comprises a releasing module, a pressurizing module and a pressure regulating module; the execution unit comprises a hydraulic cylinder; the release module comprises a pilot-operated release valve and at least three large-flow high-speed switch valves which are connected in parallel, and is used for quickly releasing high-pressure oil of the hydraulic cylinder; the pressurization module comprises a pilot-operated type pressurization valve and at least three large-flow high-speed switch valves connected in parallel and is used for rapidly injecting high-pressure oil into the hydraulic cylinder. The pressure regulating module achieves the constant pressure regulating function on the hydraulic system and achieves the on-off function of a hydraulic cylinder and an oil tank. Through the combination of the unique pilot-operated type one-way valve design and the reverse pressurizing technology, ultra-fast pressure relief response within 1ms is achieved, and meanwhile the stability and reliability of system work are guaranteed. The system is particularly suitable for special occasions where a hydraulic system needs to generate a step excitation signal, such as a gyroscope test turntable and the like.

Description

Technical Field

[0001] The present invention belongs to the technical field of construction machinery and relates to a hydraulic system capable of achieving high-speed pressure relief. Background Art

[0002] With the rapid development of precision instruments and high-end equipment manufacturing technologies, higher requirements are put forward for the response speed of hydraulic systems. Especially in fields such as gyroscope testing, aerospace, and precision machining, it is required that the hydraulic system can complete the pressure relief action within an extremely short time to meet the needs of rapid braking of the equipment.

[0003] Due to the compressibility of hydraulic oil, pipeline cavity effect, and the limitation of valve response speed in traditional hydraulic braking systems, their pressure relief response time is usually in the order of dozens of milliseconds, making it difficult to meet the high-speed pressure relief requirement within 1 ms. In the prior art, although high-speed switching valves have a fast response speed, they are limited by electromagnetic force and flow capacity and are difficult to achieve rapid response under large-flow conditions; while ordinary check valves have a large flow capacity but a slow response speed. In addition, during the pressure relief process of traditional hydraulic systems, the return movement of the hydraulic cylinder piston rod is only driven by external load force, and the pressure relief speed is limited, further affecting the overall response performance of the system. Summary of the Invention

[0004] In view of the above technical deficiencies, the present invention provides a hydraulic system capable of achieving high-speed pressure relief, which can complete the pressure relief action within 1 ms, overcomes the problems such as slow pressure relief speed in the prior art, and is particularly suitable for special scenarios requiring ultra-fast pressure relief at the millisecond level.

[0005] The technical solution adopted by the present invention to solve the above problems is as follows: A hydraulic system capable of achieving high-speed pressure relief, characterized in that:

[0006] It includes a hydraulic station unit, an execution unit, and a valve group;

[0007] The valve group includes a release module, a pressure boosting module, and a pressure regulating module;

[0008] The hydraulic station unit provides a pressure oil source for the system;

[0009] The execution unit includes a hydraulic cylinder;

[0010] The release module includes a pilot-operated release valve and at least three parallel large-flow high-speed switching valves for quickly releasing the high-pressure oil in the hydraulic cylinder;

[0011] The pressure boosting module includes a pilot-operated pressure boosting valve and at least three parallel large-flow high-speed switching valves for quickly injecting high-pressure oil into the hydraulic cylinder;

[0012] The pressure regulating module realizes the constant pressure regulation function for the hydraulic system and the on-off function between the hydraulic cylinder and the fuel tank.

[0013] Further, the hydraulic station unit includes: a motor and a plunger pump driven by the motor, which provides a pressure source for the entire hydraulic system; the plunger pump is respectively connected to the release module, the boosting module and the pressure regulating module through a main pipeline;

[0014] A first branch and a second branch are connected to the main pipeline. An accumulator is provided on the first branch, and an accumulator is provided on the second branch. The accumulator is used to reduce the hydraulic shock caused by the sudden start of the plunger pump and increase the service life of the pump; the accumulator plays a role in maintaining pressure and stabilizing pressure and reducing pressure pulsation; the accumulators all need to be precharged with nitrogen.

[0015] Further, a check valve is provided on the main pipeline of the hydraulic station unit. The check valve is located between the plunger pump and the first branch. The check valve and the accumulator jointly realize the pressure maintaining function, which can avoid the continuous operation of the motor and the plunger pump; a manual switch valve is connected after the accumulator on the first branch. After the hydraulic system works, the accumulators will store high-pressure oil for a long time. Before disassembling and repairing the hydraulic system, the accumulators need to be depressurized through the manual switch.

[0016] Further, a high-pressure filter is also provided on the main pipeline of the hydraulic station unit, which is used to filter impurities in the hydraulic oil flowing into the valve group; a third branch is connected to the main pipeline, and an adjustable overflow valve is provided on the third branch, which is used to set the working pressure of the system; an electromagnetic switch valve is provided after the accumulator on the second branch, which is responsible for realizing the function of unloading and returning oil of the plunger pump when the hydraulic cylinder does not work.

[0017] Further, in the pressure relief module and the boosting module: the number of high-speed switch valves connected to the pilot chambers of the pilot-operated release valve and the pilot-operated boosting valve is 3 each, and the total pilot flow rate is 120 L / min, realizing the rapid release of the pilot chamber pressure; the diameter of the lifting valve of the pilot-operated release valve and the pilot-operated boosting valve is 14 mm, the diameter of the valve hole is 12 mm, the half angle of the lifting valve is 45°, and the valve core moves under the action of the liquid pressure, meeting the requirements of large flow rate and fast response of the system; a throttle valve is provided on the pilot chamber oil circuit, and the diameter of the throttle hole is 1 mm, which generates a large flow resistance in the oil circuit during the pressure relief moment to limit the flow rate, and plays a unloading role during the rest of the working time.

[0018] Further, the pressure regulating module includes solenoid switch valves, and the solenoid switch valves realize the constant pressure regulation function of the hydraulic system; the solenoid switch valve realizes the on-off function between the hydraulic cylinder and the fuel tank.

[0019] Further, the boosting module also includes an accumulator, the function of which is to provide a large amount of high-pressure hydraulic oil in a short time during the reverse pressurization process of the hydraulic system, and it needs to be precharged with nitrogen.

[0020] Further, an accumulator is also included in the release module. Its function is relatively special. Its main function is to accommodate the released hydraulic oil and does not require filling with high-pressure gas.

[0021] Further, the system also includes: a pressure sensor responsible for real-time monitoring of the pressure in the rodless cavity of the hydraulic cylinder; a pressure sensor responsible for real-time monitoring of the pressure of the hydraulic oil flowing out of the hydraulic station; a temperature sensor for monitoring the temperature of the hydraulic oil.

[0022] Further, the above-mentioned pilot-operated pressure relief valve is of a pilot-controlled cone valve structure, the pilot-operated pressure booster valve is of a pilot-controlled cone valve structure, and the hydraulic cylinder is connected to the valve group by a rigid pipe.

[0023] Advantages of the present invention:

[0024] 1. The pressure relief response time is fast, and the load force can be unloaded from 130 kN to zero within 1 ms, meeting the ultra-fast pressure relief requirements of high-speed equipment;

[0025] 2. Adopting a pilot-controlled cone valve structure, it has a large flow capacity and can handle a flow rate of up to 600 L / min instantaneously;

[0026] 3. The innovative reverse pressure charging technology not only speeds up the pressure relief speed but also avoids the impact and rebound of the piston rod during the return stroke;

[0027] 4. By precisely controlling the triggering timing of the pressure booster module and the pressure relief module, the pressure fluctuation during the pressure relief process is optimized;

[0028] 5. The modular design is convenient for maintenance and fault diagnosis, and the system has high reliability. Description of the Drawings

[0029] Figure 1 It is the schematic diagram of the hydraulic system provided by the embodiment of the present invention;

[0030] In the figure: 1 - plunger pump, 2 - adjustable overflow valve, 3, 6, 16, 17 - accumulators, 4, 23 - detection elements (detection element 4 includes a pressure sensor and a temperature sensor, detection element 23 includes a pressure sensor), 5, 20, 21, 22 - electromagnetic solenoid valves, 7 - check valve, 8 - manual switch valve, 9 - high-pressure filter, 10, 11, 12, 13, 14, 15 - large-flow high-speed switch valves, 18, 19 - throttle valves, 24 - hydraulic cylinder, 25 - pilot-operated release valve, 26 - pilot-operated pressure booster valve. Detailed Embodiments

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention.

[0032] Refer to the attached Figure 1 , the present invention proposes a hydraulic system capable of achieving high-speed pressure relief, including a hydraulic station unit, an execution unit, and a valve group; the valve group includes a release module, a boosting module, and a pressure regulating module; the hydraulic station unit provides a pressure oil source for the system; the execution unit includes a hydraulic cylinder 24 and a load mechanism that interacts with its piston rod. This system is applicable to both single-acting hydraulic cylinders and double-acting hydraulic cylinders. The following description takes the double-acting hydraulic cylinder as an example.

[0033] The release module includes a pilot-operated release valve 25 and at least three parallel large-flow high-speed switching valves, which are used to quickly release the high-pressure oil in the rodless cavity of the hydraulic cylinder 24; the boosting module includes a pilot-operated boosting valve 26 and at least three parallel large-flow high-speed switching valves, which are used to quickly inject high-pressure oil into the rod cavity of the hydraulic cylinder 24; the pressure regulating module realizes the constant pressure regulation function of the hydraulic system and the on-off function between the hydraulic cylinder 24 and the fuel tank.

[0034] Specifically, refer to the attached Figure 1 , the hydraulic station unit includes a motor and a piston pump 1 driven by it, which provides a pressure source for the hydraulic system; the piston pump 1 is respectively connected to the release module, the boosting module, and the pressure regulating module through a main pipeline; a first branch and a second branch are connected to the main pipeline. An accumulator 3 is provided on the first branch, and an accumulator 6 is provided on the second branch. The accumulator 6 is used to reduce the hydraulic shock caused by the sudden start of the piston pump 1 and increase the service life of the pump; the accumulator 3 plays a role in maintaining pressure and stabilizing pressure and reducing pressure pulsation; both accumulators 3 and 6 need to be precharged with nitrogen.

[0035] Specifically, refer to the attached Figure 1 , a check valve 7 is provided on the main pipeline of the hydraulic station unit. The check valve 7 is located between the piston pump 1 and the first branch. The check valve 7 and the accumulator 3 jointly realize the pressure maintaining function and can avoid the continuous operation of the motor and the piston pump 1; a manual switch valve 8 is connected after the accumulator 3 on the first branch. After the hydraulic system works, high-pressure oil will be stored in the accumulators 3 and 17 for a long time. Before disassembling and repairing the hydraulic system, the accumulators 3 and 17 need to be depressurized through the manual switch.

[0036] Specifically, refer to the attached Figure 1 , a high-pressure filter 9 is also provided on the main pipeline of the hydraulic station unit to filter out impurities in the hydraulic oil flowing into the valve group; a third branch is connected to the main pipeline, and an adjustable relief valve 2 is provided on the third branch to set the system working pressure; an electromagnetic switch valve 5 is provided on the second branch after the accumulator 6 to be responsible for realizing the function of unloading and returning oil of the plunger pump 1 when the hydraulic cylinder 24 is not working.

[0037] Refer to the attached Figure 1 , in the pressure relief module and the pressure boosting module: the number of high-speed switch valves connected to the pilot chambers of the pilot-operated relief valve 25 and the pilot-operated pressure boosting valve 26 is 3 each, and the total pilot flow rate is 120 L / min to realize the rapid release of the pilot chamber pressure; the lift valve diameters of the pilot-operated relief valve 25 and the pilot-operated pressure boosting valve 26 are 14 mm, the valve hole diameter is 12 mm, the lift valve half angle is 45°, and the valve core acts under the action of liquid pressure to meet the requirements of large flow rate and fast response of this system; throttle valves 18 and 19 are provided on the pilot chamber oil circuit, and the throttle hole diameter is 1 mm, which generates a large flow resistance in the oil circuit during the instant of pressure relief to limit the flow rate, and plays a role of unloading during the remaining working time.

[0038] Refer to the attached Figure 1 , the pressure regulating module includes electromagnetic switch valves 20, 21, and 22. The electromagnetic switch valves 20 and 21 realize the constant pressure regulating function of the hydraulic system; the electromagnetic switch valve 22 realizes the on-off function between the hydraulic cylinder 24 and the fuel tank.

[0039] Specifically, refer to the attached Figure 1 , the pressure boosting module also includes an accumulator 17, and its function is to provide a large amount of high-pressure hydraulic oil in a short time during the reverse pressure charging process of the hydraulic system, and nitrogen needs to be pre-charged.

[0040] Specifically, refer to the attached Figure 1 , the release module also includes an accumulator 16, and its function is relatively special. Its main function is to accommodate the released hydraulic oil and does not need to be filled with high-pressure gas.

[0041] Specifically, refer to the attached Figure 1 , the system also includes: a pressure sensor 23, which is responsible for real-time monitoring of the pressure in the rodless chamber of the hydraulic cylinder; a pressure sensor 4, which is responsible for real-time monitoring of the pressure of the hydraulic oil flowing out of the hydraulic station; a temperature sensor 4, which monitors the temperature of the hydraulic oil.

[0042] Specifically, refer to the attached Figure 1 , the above-mentioned pilot-operated relief valve 25 is of a pilot-controlled cone valve structure, the pilot-operated pressure boosting valve 26 is of a pilot-controlled cone valve structure, the hydraulic cylinder 24 is connected to the valve group by a rigid pipe, and the valve group is connected to the hydraulic station unit by a high-pressure rubber hose.

[0043] All components in the hydraulic schematic diagram except the hydraulic station and the hydraulic cylinder are integrated on a valve block, that is, the release module, the boosting module, and the pressure regulating module are connected together through the internal oil circuit of the valve block.

[0044] Specifically, refer to the appendix Figure 1 , the pilot chamber of the pilot-operated release valve of the release module has four branches. The first, second, and third branches are used to connect three large-flow high-speed switching valves 10, 11, and 12 in parallel to quickly release the pressure in the pilot chamber. The oil circuits at the rear ends of the three large-flow high-speed switching valves converge and are connected to the accumulator 16 and the fuel tank; a throttle valve 18 is provided on the fourth branch of the pilot chamber to achieve the function of throttling during large flow and connecting during small flow. The rear end of the throttle valve 16 is connected to the main pipeline.

[0045] Specifically, refer to the appendix Figure 1 , the oil inlet of the pilot-operated release valve of the release module is connected to the rodless cavity of the hydraulic cylinder, and the oil outlet is connected to the fuel tank.

[0046] Specifically, refer to the appendix Figure 1 , the pilot chamber of the pilot-operated boosting valve of the boosting module has four branches. The first, second, and third branches are used to connect three large-flow high-speed switching valves 13, 14, and 15 in parallel to quickly release the pressure in the pilot chamber. The oil circuits at the rear ends of the three large-flow high-speed switching valves converge and are connected to the fuel tank; a throttle valve 19 is provided on the fourth branch of the pilot chamber to achieve the function of throttling during large flow and connecting during small flow. An accumulator 17 is provided at the rear end of the throttle valve 16 and is connected to the main pipeline. The accumulator 17 is used to provide sufficient instantaneous flow during the reverse charging process.

[0047] Specifically, refer to the appendix Figure 1 , the oil inlet of the pilot-operated boosting valve of the boosting module is connected to the rod chamber of the hydraulic cylinder, and the oil outlet is connected to the accumulator 17.

[0048] Specifically, refer to the appendix Figure 1 , the electromagnetic switching valve 21 of the pressure regulating module is arranged between the main pipeline and the rodless cavity of the hydraulic cylinder to realize the on-off function between the high-pressure oil of the hydraulic station and the rodless cavity of the hydraulic cylinder; the electromagnetic switching valve 20 is arranged between the rodless cavity of the hydraulic cylinder and the fuel tank. A detection element 23 is arranged between the electromagnetic switching valve 20 and the rodless cavity of the hydraulic cylinder to realize the pressure adjustment function. When the detection element 23 detects that the pressure in the rodless cavity is too high, it opens the electromagnetic switching valve 20 to release the pressure; the electromagnetic switching valve 22 is arranged between the rod chamber of the hydraulic cylinder and the fuel tank to release the hydraulic oil in the rod chamber when the piston rod outputs force outward.

[0049] The control signal timing of the release module and the boosting module needs to be determined according to the actual structure of the execution unit and the optimal state is obtained through debugging.

[0050] The specific working process of the hydraulic system proposed by the present invention is as follows:

[0051] Motor startup process: When the motor starts, first open the electromagnetic switch valve 5, and all other valves are in the closed state. After the motor speed stabilizes, close the electromagnetic switch valve 5. The high-pressure oil closes the release main valve and the boosting main valve through the throttle valves 18 and 19, and completes the charging work of the accumulators 3 and 17. The left and right rod chambers of the hydraulic cylinder 24 communicate with the oil tank through the electromagnetic switch valve 22.

[0052] Pressurization and pressure holding process: When pressurization is required, open the electromagnetic switch valve 21. At this time, the high-pressure oil enters the rodless chamber of the hydraulic cylinder 24, and the piston rod outputs a force. When the pressure sensor 23 monitors that the pressure in the rodless chamber reaches the required pressure, close the electromagnetic switch valve 21; when the pressure in the rodless chamber is too high, open the electromagnetic switch valve 20 to reduce the pressure.

[0053] Pressure relief process: When pressure relief is required, the ordinary electromagnetic switch valves 20 and 22 should act in advance to ensure that when the large-flow high-speed switch valves of the boosting module and the release module are opened, the ordinary electromagnetic switch valves 20 and 22 are completely closed. Open the six large-flow high-speed switch valves of the boosting module and the release module, and the boosting main valve and the release main valve are opened respectively. The high-pressure oil enters the left and right rod chambers of the hydraulic cylinder 24 through the boosting main valve to push the two piston rods to move back. The high-pressure oil in the rodless chamber is quickly released through the release main valve and flows into the accumulator 16, so that the force of the hydraulic cylinder 24 is quickly unloaded.

[0054] The above are only the embodiments of the present invention, and do not limit the protection scope of the present invention. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied to other related system fields, shall be equally included in the protection scope of the present invention.

Claims

1. A hydraulic system capable of achieving high-speed pressure relief, characterized in that: It includes hydraulic station unit, execution unit and valve group; The valve group includes a release module, a boost module and a pressure regulating module; The hydraulic station unit provides a pressure oil source for the system; The execution unit comprises a hydraulic cylinder (24); The release module comprises a pilot release valve (25) and at least three parallel high-flow high-speed switch valves, which are used to quickly release the high-pressure oil of the hydraulic cylinder (24); The boosting module comprises a pilot boosting valve (26) and at least three parallel high-flow high-speed switch valves, which are used to quickly inject high-pressure oil into the hydraulic cylinder (24); The pressure regulating module realizes a constant pressure regulating function for the hydraulic system, and realizes an on-off function between the hydraulic cylinder (24) and the oil tank.

2. A hydraulic system capable of achieving high-speed pressure relief according to claim 1, characterized in that: The hydraulic station unit comprises a motor and a plunger pump (1) driven by the motor, which provides a pressure source for the hydraulic system; the plunger pump (1) is respectively connected to the release module, the boost module and the pressure regulating module through a main pipeline; The main line is connected to a first branch line and a second branch line, the first branch line is provided with an accumulator (3), the second branch line is provided with an accumulator (6), and both the accumulator (6) and the accumulator (3) need to be pre-charged with nitrogen.

3. A hydraulic system capable of achieving high-speed pressure relief according to claim 2, characterized in that: A one-way valve (7) is provided on the main line of the hydraulic station unit. The one-way valve (7) is located between the plunger pump (1) and the first branch line. The one-way valve (7) and the accumulator (3) jointly realize a pressure-maintaining function. A manual switch valve (8) is connected to the first branch line after the accumulator (3).

4. A hydraulic system capable of achieving high-speed pressure relief according to claim 3, characterized in that: The main line of the hydraulic station unit is also provided with a high-pressure filter (9) for filtering out impurities in the hydraulic oil flowing into the valve group; the main line is connected to a third branch line, and an adjustable relief valve (2) is provided on the third branch line for setting the system working pressure; the second branch line is provided with an electromagnetic switch valve (5) after the accumulator (6), which is responsible for realizing the function of unloading and returning oil to the plunger pump (1) when the hydraulic cylinder (24) is not working.

5. A hydraulic system capable of achieving high-speed pressure relief according to any one of claims 1 to 4, characterized in that: In the pressure relief module and the boosting module: the number of high-speed switch valves connected to the pilot chambers of the pilot release valve (25) and the pilot boosting valve (26) are both 3, and the total pilot flow is 120L / min, so as to achieve rapid release of the pilot chamber pressure; the diameter of the lifting valve of the pilot release valve (25) and the pilot boosting valve (26) is 14mm, the diameter of the valve hole is 12mm, and the half angle of the lifting valve is 45°; a throttle valve (18, 19) is arranged on the pilot chamber oil circuit, and the diameter of the throttle hole is 1mm.

6. A hydraulic system capable of achieving high-speed pressure relief according to claim 5, characterized in that: The pressure regulating module comprises electromagnetic switch valves (20, 21, 22), wherein the electromagnetic switch valves (20, 21) realize the constant pressure regulating function of the hydraulic system; and the electromagnetic switch valve (22) realizes the on-off function of the hydraulic cylinder (24) and the oil tank.

7. A hydraulic system capable of achieving high-speed pressure relief according to claim 6, characterized in that: The boosting module also includes an accumulator (17), which has the function of providing a large amount of high-pressure hydraulic oil in a short time during the reverse charging process of the hydraulic system, and needs to be pre-charged with nitrogen.

8. A hydraulic system capable of achieving high-speed pressure relief according to claim 7, characterized in that: The release module also includes an accumulator (16) whose function is to contain the released hydraulic oil without the need to be filled with high-pressure gas.

9. A hydraulic system capable of achieving high-speed pressure relief according to claim 8, characterized in that: The system further comprises: a pressure sensor (23) for real-time monitoring of the pressure of the hydraulic cylinder; a pressure sensor (4) for real-time monitoring of the pressure of the hydraulic oil flowing out of the hydraulic station; and a temperature sensor (4) for monitoring the temperature of the hydraulic oil.

10. A hydraulic system capable of achieving high-speed pressure relief according to claim 9, characterized in that: The pilot-operated release valve (25) is a pilot-controlled cone valve structure, the pilot-operated booster valve (26) is a pilot-controlled cone valve structure, and the hydraulic cylinder (24) is connected to the valve group by a hard pipe.

Images