Pump control valve testing device and testing method thereof

Abstract

The invention relates to the technical field of valve test devices, and discloses a pump control valve test device and a test method thereof.The pump control valve test device comprises a test block, a cylinder sleeve, a displacement detection device and a pressure detection device, a test channel penetrating through the two ends of the test block, a test oil inlet and a flow guide channel are formed in the test block, and the test oil inlet and the flow guide channel are communicated with the test channel; a valve oil inlet of the tested valve is communicated with the testing oil inlet, a valve element in the tested valve moves, and the valve oil inlet is selectively communicated with a first working oil port between a variable piston and a valve sleeve of the tested valve through a flow guide channel; the cylinder sleeve is installed on the test block and communicated with the test channel, a load piston is movably arranged in the valve sleeve in the axial direction of the valve sleeve, the variable piston abuts against the load piston, and an elastic piece is arranged between the load piston and the end, not connected with the test block, of the cylinder sleeve. A test head of the displacement detection device is connected with the load piston; the pressure detection device is used for detecting the pressure of the valve oil inlet. According to the testing device, the pump control valve can be separated from the pump to be tested independently.

Description

Technical Field

[0001] This invention relates to the field of valve testing equipment technology, and in particular to a pump control valve testing device and its testing method. Background Technology

[0002] Conventional hydraulic valve testing typically involves measuring pressure and flow curves, which directly reflect the performance of the valve under test. However, this testing method is not suitable for performance testing of hydraulic pump variable power control valves (hereinafter referred to as pump-controlled valves). The industry practice is to assemble the valve and pump, and then test the relationship between the pump's input power and output pressure to evaluate the valve's performance. Because hydraulic valve manufacturers lack the necessary testing facilities for hydraulic pumps, pump-controlled valve manufacturers do not conduct factory testing. They can only determine the valve's quality after the pump manufacturer completes the pump assembly and performs assembly testing. This significantly reduces the production pass rate of the pumps. Summary of the Invention

[0003] The purpose of this invention is to provide a pump control valve testing device and its testing method, enabling the pump control valve to be tested independently of the pump.

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

[0005] This invention provides a pump control valve testing device, comprising:

[0006] The test block has a test channel running through both ends and a test inlet and a flow guide channel connected to the test channel. The valve under test is installed in the test channel. The valve inlet of the valve under test is connected to the test inlet. The valve core inside the valve under test moves. The valve inlet is selectively connected to the first working port between the variable piston and the valve sleeve of the valve under test through the flow guide channel.

[0007] A cylinder liner is installed on the test block and connected to the test channel. A load piston is movably arranged inside the valve sleeve along its axial direction. The variable piston abuts against the load piston. An elastic element is provided between the load piston and the end of the cylinder liner that is not connected to the test block.

[0008] A displacement detection device is installed on the cylinder liner, and the test head of the displacement detection device is connected to the load piston;

[0009] A pressure detection device is installed on the test block to detect the pressure at the valve inlet.

[0010] The test block of this pump-controlled valve testing device is equipped with a test channel and a test inlet and a guide channel connected to the test channel. The valve under test is installed in the test channel, and the valve inlet of the valve under test is connected to the test inlet. The valve core inside the valve under test moves, and the valve inlet is selectively connected to the first working port between the variable piston and the valve sleeve of the valve under test through the guide channel. The valve sleeve is installed on the test block and connected to the test channel. A load piston is movably installed in the valve sleeve along its axial direction. The variable piston and the load piston abut against each other. The extension and movement of the variable piston will drive the load piston to move synchronously. An elastic element is installed between the load piston and the end of the cylinder sleeve that is not connected to the test block. The elastic element simulates the load force generated by driving the swashplate to swing under real working conditions. The test block is also equipped with a displacement detection device and a pressure detection device. The test head of the displacement detection device is connected to the load piston, and the displacement of the variable piston and the load piston is detected by the displacement detection device. The pressure detection device detects the pressure at the valve inlet of the valve under test.

[0011] The displacement of a variable displacement pump is directly proportional to the swashplate angle, which is controlled by the displacement of the variable piston. Therefore, it is only necessary to collect the variable piston displacement signal and the valve inlet pressure signal of the valve under test, plot the curves based on the displacement and pressure signals, and judge the working performance of the pump control valve based on the plotted curves. This testing device can simulate the working conditions of a variable displacement pump swashplate and the variable power characteristics of an oil pump, realizing the function of testing the pump control valve independently of the pump.

[0012] As a preferred embodiment of the above-mentioned pump control valve testing device, the test block is provided with a test overflow port that is connected to the test channel, and when the variable piston extends to the limit position, the valve overflow port of the valve under test is connected to the test overflow port.

[0013] When the variable piston extends to its limit position, the valve overflow port of the valve under test is connected to the test overflow port, thereby releasing the pressure and providing safety protection.

[0014] As a preferred embodiment of the above-mentioned pump control valve testing device, the flow guiding channel includes a first connecting channel and two longitudinal channels. The two longitudinal channels are arranged at intervals along the length direction of the test channel, and both longitudinal channels are connected to the test channel. The first connecting channel connects the two longitudinal channels. One of the longitudinal channels is connected to the first working oil port of the valve, and the other longitudinal channel can be connected to a second working oil port located on one side of the first working oil port. The valve core in the valve under test moves, and the first working oil port and the second working oil port are selectively connected.

[0015] The valve core inside the test valve moves, and the first working oil port and the second working oil port are selectively connected, thereby achieving selective connection between the valve inlet and the first working oil port. The above-mentioned guide channel structure is simple and easy to manufacture.

[0016] As a preferred embodiment of the above-mentioned pump control valve testing device, a first plug is installed at the end of the longitudinal channel that is not connected to the testing channel; a second plug is installed at the end of the connecting channel that is not connected to the longitudinal channel.

[0017] The first plug is used to seal the process port of the longitudinal channel to prevent oil leakage; the second plug is used to seal the process port of the connecting channel to prevent oil leakage.

[0018] As a preferred embodiment of the above-mentioned pump control valve testing device, the test block is provided with a detection channel connected to the test channel. The detection channel includes an installation channel and a second connecting channel. The installation channel is arranged parallel to the valve inlet. The second connecting channel connects the installation channel and the test inlet. The pressure detection device extends into the installation channel.

[0019] The aforementioned detection channel is connected to the valve inlet via a second connecting channel, allowing the pressure signal from the valve inlet of the tested valve to be directly acquired via a pressure detection device.

[0020] As a preferred embodiment of the above-mentioned pump control valve testing device, the cylinder liner is provided with a cavity, the cavity including a first cavity and a second cavity that are connected. The inner diameter of the first cavity is larger than the inner diameter of the second cavity. The position where the first cavity and the second cavity are connected forms a stepped surface. The load piston includes a main body, which is movably disposed in the first cavity and can abut against the stepped surface.

[0021] The cylinder liner has a cavity including a first cavity and a second cavity. The inner diameter of the first cavity is larger than that of the second cavity. The main body of the load piston is movably disposed in the first cavity. The steps of the first and second cavities act as a limit to the main body. This structure is simple and easy to manufacture.

[0022] As a preferred embodiment of the above-mentioned pump control valve testing device, the load piston further includes a connecting rod, one end of which is connected to the main body, and the other end of which extends into the second cavity and is connected to the test head of the displacement detection device. The elastic element is sleeved on the connecting rod and abuts against the main body.

[0023] The load piston also includes a connecting rod, which facilitates connection to the test head of the displacement detection device; moreover, the elastic element is sleeved on the connecting rod and abuts against the main body to ensure the positioning and installation of the elastic element.

[0024] As a preferred embodiment of the above-mentioned pump control valve testing device, the load piston is detachably connected to the test block.

[0025] The load piston and the test block are detachably connected, which facilitates the connection and separation of the two, and thus facilitates maintenance and replacement.

[0026] The present invention also provides a testing method for a pump control valve testing device, wherein the above-mentioned pump control valve testing device is used for testing, and the testing method for the pump control valve testing device includes the following steps:

[0027] The valve under test is installed in the test channel of the pump control valve test device;

[0028] During the pressurization and depressurization processes, the pump control valve testing device detects the displacement of the load piston and the variable piston through the displacement detection device, and detects the pressure at the valve inlet of the valve under test through the pressure detection device. Based on the displacement and the pressure, a curve is plotted, and the working performance of the valve under test is determined based on the curve.

[0029] The testing method of this pump-controlled valve testing device involves installing the valve under test in the test channel of the device. During the pressurization and depressurization processes, the device detects the displacement of the load piston and the variable piston using a displacement detection device, and detects the pressure at the valve inlet using a pressure detection device. Based on the displacement and pressure, a curve is plotted, and the working performance of the valve under test is determined according to the curve. This testing method simulates the working condition of a variable pump swashplate and the variable power characteristics of an oil pump, enabling the pump-controlled valve to be tested independently of the pump.

[0030] As a preferred embodiment of the testing method for the aforementioned pump-controlled valve testing device, during the pressurization and depressurization processes, the pump-controlled valve testing device detects the displacement of the load piston and the variable piston using the displacement detection device, and detects the pressure at the valve inlet of the tested valve using the pressure detection device. A curve is plotted based on the displacement and the pressure, and the working performance of the tested valve is determined based on the curve, including the following steps:

[0031] Outbound curve acquisition: During the process of the pressure at the valve inlet increasing from zero to the rated pressure, the displacement of the load piston and the variable piston is detected by the displacement detection device, and the pressure at the valve inlet is detected by the pressure detection device. The outbound curve is plotted based on the displacement and pressure during the pressure increase process.

[0032] Return curve acquisition: During the process of the pressure at the valve inlet dropping from the rated pressure to zero, the displacement of the load piston and the variable piston is detected by the displacement detection device, and the pressure at the valve inlet is detected by the pressure detection device. The return curve is plotted based on the displacement and pressure during the pressure reduction process.

[0033] The performance of the valve under test is determined based on the smoothness of the outgoing and returning curves and the maximum hysteresis between the two curves.

[0034] The working performance of the valve under test is judged by the smoothness of the outgoing and returning curves and the maximum hysteresis between the two curves. This test method simulates the working condition of the swashplate of the variable pump and the test process is relatively simple.

[0035] The beneficial effects of this invention are:

[0036] The pump-controlled valve testing device proposed in this invention includes a test block with a test channel, a test inlet, and a guide channel connected to the test channel. The valve under test is installed in the test channel, and its valve inlet is connected to the test inlet. The valve core inside the valve under test moves, and the valve inlet is selectively connected to the first working port between the variable piston and the valve sleeve of the valve under test through the guide channel. The valve sleeve is installed on the test block and connected to the test channel. A load piston is movably installed axially inside the valve sleeve, and the variable piston and the load piston abut against each other. The extension and movement of the variable piston will drive the load piston to move synchronously. An elastic element is provided between the load piston and the end of the cylinder sleeve that is not connected to the test block. The elastic element simulates the load force generated by driving the swashplate to swing under real working conditions. The test block is also equipped with a displacement detection device and a pressure detection device. The test head of the displacement detection device is connected to the load piston, and the displacement of the variable piston and the load piston is detected by the displacement detection device. The pressure detection device detects the pressure at the valve inlet of the valve under test.

[0037] The displacement of a variable displacement pump is directly proportional to the swashplate angle, which is controlled by the displacement of the variable piston. Therefore, it is only necessary to collect the displacement signal of the variable piston and the pressure signal at the valve inlet of the test valve. A curve is plotted based on the displacement and pressure signals, and the performance of the pump-controlled valve is determined based on the plotted curve. This testing device can simulate the working conditions of a variable displacement pump swashplate and the variable power characteristics of an oil pump, enabling the pump-controlled valve to be tested independently of the pump.

[0038] The testing method of the pump-controlled valve testing device proposed in this invention involves installing the valve under test in the test channel of the pump-controlled valve testing device. During the pressurization and depressurization process, the pump-controlled valve testing device detects the displacement of the load piston and the variable piston through a displacement detection device, and detects the pressure at the valve inlet of the valve under test through a pressure detection device. Based on the displacement and pressure, a curve is plotted, and the working performance of the valve under test is judged based on the curve. This testing method simulates the working condition of the variable pump swashplate and the variable power characteristics of the oil pump, realizing the function of testing the pump-controlled valve independently of the pump. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the structure of the valve under test provided by the present invention;

[0040] Figure 2 This is a schematic diagram of the structure of the test valve installed in the pump control valve testing device provided by the present invention;

[0041] Figure 3 This is a schematic diagram of the pump control valve testing device provided by the present invention;

[0042] Figure 4 yes Figure 3 A sectional view along line AA.

[0043] Figure 5 This is a cross-sectional view of the test block provided by the present invention;

[0044] Figure 6 This is a schematic diagram of the initial state of the pump control valve testing device provided by the present invention;

[0045] Figure 7 This is a schematic diagram of the working state of the pump control valve testing device provided by the present invention;

[0046] Figure 8 This is a schematic diagram of the pump control valve testing device under pressure relief conditions provided by the present invention.

[0047] In the picture:

[0048] 1. Test block; 11. Test channel; 12. Test oil inlet; 13. Guide channel; 131. First connecting channel; 132. Longitudinal channel; 133. First plug; 134. Second plug; 14. Test overflow port; 15. Detection channel; 151. Installation channel; 152. Second connecting channel;

[0049] 2. Cylinder liner; 21. First chamber; 22. Second chamber;

[0050] 3. Load piston; 31. Main body; 32. Connecting rod;

[0051] 4. Elastic components;

[0052] 5. Displacement detection device; 51. Test head;

[0053] 6. Pressure detection device;

[0054] 100. Test valve; 1001. Valve inlet; 1002. First working port; 1003. Second working port; 1005. Valve overflow port; 1006. Valve drain port; 102. Valve core; 103. Variable piston; 104. Valve sleeve; 106. Valve seat; 107. Displacement feedback rod; 108. Pressure regulating spring. Detailed Implementation

[0055] 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.

[0056] 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.

[0057] 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.

[0058] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0059] This embodiment provides a pump-controlled valve testing device for testing the operating performance of pump-controlled valves, such as... Figure 1As shown, the pump control valve includes a valve seat 106, a valve sleeve 104, and a valve core 102. The valve sleeve 104 is connected to and communicates with the valve seat 106. The valve core 102 is movably disposed inside the valve sleeve 104. A displacement feedback rod 107 is movably disposed inside the valve core 102. One end of the displacement feedback rod 107 extends out of the valve core 102 and the valve sleeve 104 and is connected to the variable piston 103. A limiting structure is provided at the other end of the displacement feedback rod 107. A pressure regulating spring 108 is provided between the variable piston 103 and the limiting mechanism and between the valve core 102 and the limiting structure. The valve sleeve 104 is provided with a valve inlet 1001. A first working port 1002 and a second working port 1003 are respectively provided on both sides of the valve inlet 1001. The first working port 1002 is located between the variable piston 103 and the valve sleeve 104. The second working port 1003 is located on the side of the valve inlet 1001 facing the valve seat 106. When oil enters the valve inlet 1001, the valve core 102 moves towards the valve seat 106, and the first working port 1002 and the second working port 1003 connect. The variable piston 103 is provided with a valve overflow port 1005 and a valve drain port 1006. The valve drain port 1006 is located at the end of the variable piston 103 furthest from the valve sleeve 104.

[0060] like Figures 2-5 As shown, the pump-controlled valve testing device includes a test block 1, a cylinder liner 2, a load piston 3, a displacement detection device 5, and a pressure detection device 6. The test block 1 has a test channel 11 extending through both ends, a test inlet 12 connected to the test channel 11, and a flow guide channel 13. The valve under test 100 is installed within the test channel 11 (see...). Figure 6 The valve inlet 1001 of the test valve 100 is connected to the test inlet 12. The valve core 102 inside the test valve 100 moves, and the valve inlet 1001 is selectively connected to the first working port 1002 between the variable piston 103 and the valve sleeve 104 of the test valve 100 through the guide channel 13. The cylinder sleeve 2 is installed on the test block 1 and connected to the test channel 11. The load piston 3 is movably arranged in the valve sleeve 104 along its axial direction. The variable piston 103 abuts against the load piston 3. An elastic element 4 is provided between the load piston 3 and the end of the cylinder sleeve 2 that is not connected to the test block 1. The displacement detection device 5 is set at the end of the cylinder sleeve 2 that is not connected to the test block 1. The test head 51 of the displacement detection device 5 is connected to the load piston 3. The pressure detection device 6 is installed on the test block 1 and is used to detect the pressure of the valve inlet 1001.

[0061] The pump-controlled valve testing device has an elastic element 4 between the load piston 3 and the end of the cylinder liner 2 that is not connected to the test block 1. The elastic element 4 simulates the load force generated by driving the swashplate to swing under real working conditions. The test head 51 of the displacement detection device 5 is connected to the load piston 3, and the displacement detection device 5 detects the displacement of the variable piston 103 and the load piston 3. The pressure detection device 6 detects the pressure at the valve inlet 1001. Since the displacement of the variable pump is directly proportional to the swashplate angle, and the swashplate angle is controlled by the displacement of the variable piston 103, it is only necessary to collect the displacement signal of the variable piston 103 of the valve under test 100 and the pressure signal of the valve inlet 1001. A curve is plotted based on the displacement and pressure signals, and the working performance of the pump-controlled valve is judged based on the plotted curve. This testing device can simulate the working conditions of the variable pump swashplate and the variable power characteristics of the oil pump, realizing the function of testing the pump-controlled valve independently of the pump.

[0062] like Figure 5 As shown, test block 1 is provided with a test overflow port 14 that is connected to test channel 11. When the variable piston 103 extends to its limit position, the valve overflow port 1005 of the valve under test 100 is connected to the test overflow port 14. When the valve overflow port 1005 of the valve under test 100 is connected to the test overflow port 14, the pressure is released, which plays a role in safety protection.

[0063] Optionally, the flow channel 13 includes a first connecting channel 131 and two longitudinal channels 132. The two longitudinal channels 132 are arranged at intervals along the length of the test channel 11, and both longitudinal channels 132 are connected to the test channel 11. The first connecting channel 131 connects the two longitudinal channels 132, one of which is connected to the first working port 1002, and the other is connected to the second working port 1003. When the valve core 102 in the test valve 100 moves, the first working port 1002 and the second working port 1003 are selectively connected. The valve inlet 1001 is selectively connected to the first working port 1002 between the variable piston 103 and the valve sleeve 104 of the test valve 100 through the aforementioned flow channel 13. The aforementioned flow channel 13 has a simple structure and is easy to manufacture.

[0064] In this embodiment, a first plug 133 is installed at the end of the longitudinal channel 132 that is not connected to the test channel 11. The first plug 133 is used to block the process port of the longitudinal channel 132 to prevent oil leakage. A second plug 134 is installed at the end of the connecting channel that is not connected to the longitudinal channel 132. The second plug 134 is used to block the process port of the connecting channel to prevent oil leakage.

[0065] Optionally, the test block 1 is provided with a detection channel 15 connected to the test channel 11. The detection channel 15 includes an installation channel 151 and a second connecting channel 152. The installation channel 151 is arranged parallel to the valve inlet 1001, and the second connecting channel 152 connects the installation channel 151 and the test inlet 12. The pressure detection device 6 extends into the installation channel 151. The installation channel 151 of the detection channel 15 is connected to the valve inlet 1001 through the second connecting channel 152, and the pressure signal of the valve inlet 1001 can be directly collected by the pressure detection device 6.

[0066] Optionally, such as Figure 4 As shown, the cylinder liner 2 is provided with a cavity, which includes a first cavity 21 and a second cavity 22 that are connected. The inner diameter of the first cavity 21 is larger than the inner diameter of the second cavity 22. The position where the first cavity 21 and the second cavity 22 are connected forms a stepped surface. The load piston 3 includes a main body 31, which is movably disposed in the first cavity 21 and can abut against the stepped surface, thereby limiting the main body 31. This structure is simple and easy to manufacture.

[0067] Optionally, the load piston 3 further includes a connecting rod 32, one end of which is connected to the main body 31, and the other end of which extends into the second cavity 22 and is connected to the test head 51 of the displacement detection device 5. An elastic element 4 is sleeved on the connecting rod 32 and abuts against the main body 31. The connecting rod 32 facilitates connection to the test head 51 of the displacement detection device 5; moreover, the elastic element 4, sleeved on the connecting rod 32 and abutting against the main body 31, ensures the proper positioning and installation of the elastic element 4.

[0068] Optionally, the load piston 3 and the test block 1 are detachably connected, facilitating their connection and separation, and thus enabling maintenance and replacement. In this embodiment, the load piston 3 is connected to the test block 1 by screws, making disassembly and assembly relatively simple. In other embodiments, the connection method between the load piston 3 and the test block 1 is not limited to screw connection; other connection methods are also possible and are not limited here, as long as a detachable connection between the two can be achieved.

[0069] like Figure 6 When the valve under test 100 is in its initial state, and the pressure at the valve inlet 1001 exceeds the set value of the pressure regulating spring 108, the oil pushes the valve core 102 to the right, connecting the first working port 1002 and the second working port 1003. The oil flows from the second working port 1003 through the guide channel 13 in the test block 1 into the first working port 1002 (see...). Figure 7The pressure oil from the first working port 1002 acts on the right side of the variable piston 103, thereby pushing the variable piston 103 to extend. The variable piston 103 then pushes the load piston 3 to the left. The load piston 3 overcomes the elastic force of the elastic element 4, which is used to simulate the load force generated by driving the swashplate to swing in real working conditions. The displacement of the variable piston 103 and the pressure of the valve inlet 1001 are converted into electrical signals by the sensor and sent to the data acquisition system.

[0070] As the pressure at the valve inlet 1001 continues to rise, the variable piston 103 continues to extend until the valve overflow port 1005 connects with the test overflow port 14 (see...). Figure 8 The pressure oil on the right side of the variable piston 103 is released, and the variable piston 103 stops moving.

[0071] When the pressure on the right side of the variable piston 103 decreases, the variable piston 103 retracts, the load piston 3 of the test device moves to the right, the displacement detection device 5 collects displacement signals in real time, and the pressure detection device 6 detects pressure signals in real time.

[0072] This embodiment also provides a testing method for a pump control valve testing device. The testing method using the aforementioned pump control valve testing device includes the following steps:

[0073] The test valve 100 is installed in the test channel 11 of the pump control valve test device;

[0074] During the pressurization and depressurization process, the pump control valve testing device detects the displacement of the load piston 3 and the variable piston 103 through the displacement detection device 5, and detects the pressure of the valve inlet 1001 of the valve under test 100 through the pressure detection device 6. Based on the displacement and pressure, a curve is plotted, and the working performance of the valve under test 100 is judged based on the curve.

[0075] The testing method of this pump-controlled valve testing device involves installing the test valve 100 in the test channel 11 of the device during testing. During the pressurization and depressurization processes, the device detects the displacement of the load piston 3 and the variable piston 103 through the displacement detection device 5, and detects the pressure at the valve inlet 1001 of the test valve 100 through the pressure detection device 6. Based on the displacement and pressure, a curve is plotted, and the working performance of the test valve 100 is determined according to the curve. This testing method simulates the working condition of the variable pump swashplate and the variable power characteristics of the oil pump, realizing the function of testing the pump-controlled valve independently of the pump.

[0076] Furthermore, during the pressurization and depressurization processes, the pump control valve testing device detects the displacement of the load piston 3 and the variable piston 103 through the displacement detection device 5, and detects the pressure at the valve inlet 1001 of the tested valve 100 through the pressure detection device 6. Based on the displacement and pressure, a curve is plotted, and the working performance of the tested valve 100 is determined according to the curve, including the following steps:

[0077] Outbound curve acquisition: During the process of increasing the pressure of valve inlet 1001 from zero to rated pressure, the displacement of load piston 3 and variable piston 103 is detected by displacement detection device 5, and the pressure of valve inlet 1001 is detected by pressure detection device 6. The outbound curve is plotted based on the displacement and pressure during the pressure increase process.

[0078] Return curve acquisition: During the process of the pressure at the valve inlet 1001 dropping from the rated pressure to zero, the displacement of the load piston 3 and the variable piston 103 is detected by the displacement detection device 5, and the pressure at the valve inlet 1001 of the tested valve 100 is detected by the pressure detection device 6. The return curve is plotted based on the displacement and pressure during the pressure reduction process.

[0079] The performance of the tested valve 100 is determined by the smoothness of the outgoing and returning curves and the maximum hysteresis between the two curves.

[0080] The working performance of the tested valve 100 is judged based on the smoothness of the outgoing and returning curves and the maximum hysteresis between the two curves. This test method simulates the working condition of the swashplate of the variable pump, and the testing process is relatively simple.

[0081] It should be noted that both the outbound and return curves have pressure on the horizontal axis and displacement on the vertical axis.

[0082] 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 pump control valve testing device, characterized in that, include: Test block (1), the test block (1) is provided with a test channel (11) that runs through both ends of it and a test oil inlet (12) and a guide channel (13) connected to the test channel (11). The test valve (100) is installed in the test channel (11). The valve oil inlet (1001) of the test valve (100) is connected to the test oil inlet (12). The valve core (102) in the test valve (100) moves. The valve oil inlet (1001) is selectively connected to the first working oil port (1002) between the variable piston (103) and the valve sleeve (104) of the test valve (100) through the guide channel (13). Cylinder liner (2), the cylinder liner (2) is installed on the test block (1) and connected to the test channel (11), a load piston (3) is movably arranged in the valve sleeve (104) along its axial direction, the variable piston (103) abuts against the load piston (3), and an elastic element (4) is provided between the load piston (3) and the end of the cylinder liner (2) that is not connected to the test block (1). A displacement detection device (5) is installed on the cylinder liner (2), and the test head (51) of the displacement detection device (5) is connected to the load piston (3); A pressure detection device (6) is installed on the test block (1) to detect the pressure at the valve inlet (1001).

2. The pump control valve testing device according to claim 1, characterized in that, The test block (1) is provided with a test overflow port (14) that is connected to the test channel (11). When the variable piston (103) extends to the limit position, the valve overflow port (1005) of the test valve (100) is connected to the test overflow port (14).

3. The pump control valve testing device according to claim 1, characterized in that, The flow channel (13) includes a first connecting channel (131) and two longitudinal channels (132). The two longitudinal channels (132) are arranged at intervals along the length direction of the test channel (11), and both longitudinal channels (132) are connected to the test channel (11). The first connecting channel (131) connects the two longitudinal channels (132). One of the longitudinal channels (132) is connected to the first working port (1002), and the other longitudinal channel (132) can be connected to the second working port (1003) located on one side of the first working port (1002). The valve core (102) in the test valve (100) moves, and the first working port (1002) and the second working port (1003) are selectively connected.

4. The pump control valve testing device according to claim 3, characterized in that, A first plug (133) is installed at the end of the longitudinal channel (132) that is not connected to the test channel (11); a second plug (134) is installed at the end of the connecting channel that is not connected to the longitudinal channel (132).

5. The pump control valve testing device according to claim 1, characterized in that, The test block (1) is provided with a detection channel (15) connected to the test channel (11). The detection channel (15) includes an installation channel (151) and a second connecting channel (152). The installation channel (151) is arranged parallel to the valve inlet (1001). The second connecting channel (152) connects the installation channel (151) and the test inlet (12). The pressure detection device (6) extends into the installation channel (151).

6. The pump control valve testing device according to any one of claims 1-5, characterized in that, The cylinder liner (2) is provided with a cavity, which includes a first cavity (21) and a second cavity (22) that are connected. The inner diameter of the first cavity (21) is larger than the inner diameter of the second cavity (22). The position where the first cavity (21) and the second cavity (22) are connected forms a stepped surface. The load piston (3) includes a body (31), which is movably disposed in the first cavity (21) and can abut against the stepped surface.

7. The pump control valve testing device according to claim 6, characterized in that, The load piston (3) also includes a connecting rod (32), one end of which is connected to the main body (31), and the other end of which extends into the second cavity (22) and is connected to the test head (51) of the displacement detection device (5). The elastic element (4) is sleeved on the connecting rod (32) and abuts against the main body (31).

8. The pump control valve testing device according to any one of claims 1-5, characterized in that, The load piston (3) is detachably connected to the test block (1).

9. A test method for a pump control valve testing device, characterized in that, The pump control valve testing device according to any one of claims 1-8 is used for testing, and the testing method of the pump control valve testing device includes the following steps: The test valve (100) is installed in the test channel (11) of the pump control valve test device; During the pressurization and depressurization process, the pump control valve testing device detects the displacement of the load piston (3) and the variable piston (103) through the displacement detection device (5), and detects the pressure of the valve inlet (1001) of the test valve (100) through the pressure detection device (6). Based on the displacement and the pressure, a curve is plotted, and the working performance of the test valve (100) is judged based on the curve.

10. The test method of the pump control valve test device according to claim 9, characterized in that, During the pressurization and depressurization process, the pump control valve testing device detects the displacement of the load piston (3) and the variable piston (103) through the displacement detection device (5), and detects the pressure at the valve inlet (1001) of the test valve (100) through the pressure detection device (6). A curve is plotted based on the displacement and the pressure. The working performance of the test valve (100) is determined based on the curve, including the following steps: Outbound curve acquisition: During the process of the pressure of the valve inlet (1001) increasing from zero to the rated pressure, the displacement of the load piston (3) and the variable piston (103) is detected by the displacement detection device (5), and the pressure of the valve inlet (1001) is detected by the pressure detection device (6). The outbound curve is plotted based on the displacement and pressure during the pressure increase process. Return curve acquisition: During the process of the pressure of the valve inlet (1001) dropping from the rated pressure to zero, the displacement of the load piston (3) and the variable piston (103) is detected by the displacement detection device (5), and the pressure of the valve inlet (1001) is detected by the pressure detection device (6). The return curve is plotted based on the displacement and pressure during the pressure reduction process. The performance of the tested valve (100) is determined based on the smoothness of the outgoing curve and the return curve, as well as the maximum hysteresis between the two curves.

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