Hydraulic valve with contact-type valve core position detection
Patent Information
- Application Number
- CN202522302963.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-30
- Publication Date
- 2026-09-01
- Estimated Expiration
- 2035-10-30
AI Technical Summary
[0005]本实用新型提供了一种接触式阀芯位置检测的液压阀，解决了现有技术中存在的阀芯具体位移量难以精准确定，导致液压控制阀精度不佳的问题
[0023]1、本实用新型通过设置在工作油口的压力传感器和设置在阀芯第二端的位移传感器，能够精准确定阀门此时的当前开度，有助于控制器将目标开度(或可理解为目标流量)和当前开度(或可理解为当前流量)进行比较，并动态调整控制指令，确保阀芯始终处于正确的位置，提高液压阀的控制精度。
Smart Images
Figure CN224706046U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of hydraulic valves, and in particular to a hydraulic valve for contact-type valve core position detection. Background Technology
[0002] In hydraulic transmission and control systems, hydraulic control valves, as core precision components controlling the operation of various mechanisms within the entire hydraulic system, directly impact the reliability, control accuracy, and lifespan of the entire system. The displacement of the valve spool within the valve body is a critical parameter, directly affecting the on / off state of the valve ports, the flow rate, and its direction, thus influencing the precise control of the actuator's movements. Therefore, accurate, reliable, and efficient detection of valve spool displacement is crucial for the performance verification, quality control, and fault diagnosis of valve products, and is essential for the precise control and reliable operation of the entire hydraulic system.
[0003] Currently, in hydraulic transmission and control systems, hydraulic, electrical, or mechanical joysticks are generally used to drive the valve core movement. In applications requiring high precision, stepper motors or servo motors are often used to control the valve core movement, relying on the motor's input parameters to calculate the valve core position. Stepper motors determine the number of motor revolutions by the number of input pulses, and then the valve core displacement is determined by multiplying the lead screw by the number of motor revolutions. However, in practical applications, due to load changes or motor matching issues, stepper motors may "miss steps," making the calculation of valve core displacement based on the number of pulses inaccurate. This approach has a certain degree of uncertainty. When using a servo motor to drive the valve core, the encoder on the servo motor shaft measures the servo motor's drive angle in real time, and a PID closed-loop control algorithm is used to determine the specific valve core displacement. This approach often requires optimization and tuning based on the specific load inertia and rigidity. Improper parameter settings can lead to slow system response, jitter, or positioning overshoot, affecting dynamic accuracy.
[0004] It is evident that existing technologies suffer from the problem of difficulty in accurately determining the specific displacement of the valve core, resulting in poor accuracy of hydraulic control valves. Utility Model Content
[0005] This invention provides a hydraulic valve for contact-type valve core position detection, which solves the problem in the prior art that the specific displacement of the valve core is difficult to determine accurately, resulting in poor accuracy of the hydraulic control valve.
[0006] This utility model provides a hydraulic valve for contact-type valve core position detection, including a valve core, a valve body, a pressure sensor, a displacement sensor, a valve core drive unit, and a controller.
[0007] The valve body has a valve core hole that runs through it along its axial direction, and the valve core is located in the valve core hole; the side wall of the valve body has an oil inlet, an oil return port and a working oil port that run through it along its radial direction; the oil inlet is connected to the oil source, the working oil port is connected to the inlet of the external load, and the oil return port is connected to the return oil tank.
[0008] The valve core drive unit is connected to the first end of the valve core and is used to drive the valve core to move between the first position and the second position along the axial direction of the valve body in order to control the opening degree of the oil inlet, oil return and working oil ports.
[0009] Pressure sensors are located at the working oil port and the oil inlet to detect the pressure difference between the working oil port and the oil inlet.
[0010] The displacement sensor includes a contact head and a telescopic contact rod. The telescopic contact rod is connected to the first end of the contact head, and the second end of the contact head abuts against the second end of the valve core to follow the movement of the valve core.
[0011] The displacement sensor, pressure sensor, and valve core drive unit are all electrically connected to the controller.
[0012] Optionally, the valve body and valve core are spool valve type three-position four-way structure.
[0013] Optionally, the working port and the return port are arranged opposite each other along the radial direction of the valve body, and the inlet port is located between the working port and the return port along the circumferential direction of the valve body.
[0014] Optionally, the working oil port includes a first oil port and a second oil port that are spaced apart along the axial direction of the valve body, with an intermediate position between the first position and the second position;
[0015] When the valve core moves to the middle position, the oil inlet is connected to the oil return port;
[0016] When the valve core moves to the first position, the oil inlet is connected to the first oil port and the oil return port is connected to the second oil port;
[0017] When the valve core moves to the second position, the oil inlet is connected to the second oil port, and the oil return port is connected to the first oil port.
[0018] Optionally, the hydraulic valve for contact-type valve core position detection also includes a first end cover and a second end cover. The first end cover is located at the end of the valve body away from the displacement sensor, and the second end cover is located at the other end of the valve body. At least a portion of the displacement sensor is located inside the second end cover.
[0019] Optionally, the outer wall hardness of the valve core is HRC > 40.
[0020] Optionally, the surface roughness Ra of the second end of the valve core is less than 1.6.
[0021] Optionally, the perpendicularity of the end face of the second end of the valve core to the valve core axis is less than 0.1.
[0022] Compared with the prior art, the beneficial effects of this utility model are as follows:
[0023] 1. This utility model, through a pressure sensor installed at the working oil port and a displacement sensor installed at the second end of the valve core, can accurately determine the current opening degree of the valve. This helps the controller compare the target opening degree (or can be understood as the target flow rate) with the current opening degree (or can be understood as the current flow rate) and dynamically adjust the control command to ensure that the valve core is always in the correct position, thereby improving the control accuracy of the hydraulic valve.
[0024] 2. Because the valve core position is accurate and controllable, it can achieve precise flow distribution. In actual use, it can accurately control the speed and torque of the valve core drive unit, avoiding the large amount of throttling loss and heat loss caused by adjusting the speed through throttling or overflow in traditional technology. This can extend the life of hydraulic oil and seals and reduce the load on the cooling system.
[0025] 3. This utility model can achieve accurate detection of valve core position, thereby enabling fault diagnosis and predictive maintenance of hydraulic systems. For example, if the valve core position is inaccurate or stuck, the system can immediately alarm to indicate valve core jamming, thus avoiding more serious failures.
[0026] 4. This utility model can predict the wear of hydraulic valves by monitoring the change trend of valve core response time in real time, thereby realizing predictive maintenance of hydraulic valves. Attached Figure Description
[0027] Figure 1 This is a cross-sectional view of the hydraulic valve for contact valve core position detection according to an embodiment of the present invention.
[0028] Figure 2 This is a schematic diagram of the electrical control connection of the hydraulic valve for contact valve core position detection according to an embodiment of this utility model.
[0029] Explanation of reference numerals in the attached figures:
[0030] 1. Hydraulic valve with contact-type valve core position detection;
[0031] 11. Valve core; 111. First end; 112. Second end; 113. Shoulder; 114. Countersinking groove;
[0032] 12. Valve body; 120. Valve core bore; 121. Oil inlet; 122. Oil return port; 123. Working oil port; 124. First oil port; 125. Second oil port;
[0033] 13. Displacement sensor; 131. Contact head; 132. Telescopic contact rod; 133. Mounting nut; 134. Signal processing box; 135. Terminal block;
[0034] 141. First end cap; 142. Second end cap;
[0035] 15. Pressure sensor; 16. Valve core drive unit; 17. Controller. Detailed Implementation
[0036] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. This embodiment is based on the technical solution of the present invention and provides detailed implementation methods and specific operating procedures; however, the scope of protection of the present invention is not limited to the following embodiments.
[0037] It should be noted that in this specification, similar reference numerals and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0038] In the description of this embodiment, it should be noted that the terms "upper", "lower", "inner", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship that the utility model product is usually placed in during use. They are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the utility model.
[0039] The terms “first”, “second”, etc., are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.
[0040] In the description of this embodiment, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set up," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this embodiment based on the specific circumstances.
[0041] To make the objectives, technical solutions, and advantages of this utility model clearer, the embodiments of this utility model will be described in further detail below with reference to the accompanying drawings.
[0042] This utility model provides a hydraulic valve 1 for contact-type valve core position detection. Please refer to [link / reference]. Figure 1 and Figure 2 It includes a valve core 11, a valve body 12, a pressure sensor 15, a displacement sensor 13, a valve core drive unit 16, and a controller 17. For example... Figure 2As shown, displacement sensor 13, pressure sensor 15 and valve core drive unit 16 are all electrically connected to controller 17.
[0043] Please see Figure 1 The valve body 12 has a valve core hole 120 extending axially therethrough, and the valve core 11 is disposed within the valve core hole 120. The side wall of the valve body 12 has an oil inlet 121, an oil return port 122, and a working oil port 123 extending radially therethrough. The oil inlet 121 is connected to an oil source, the working oil port 123 is connected to the inlet of an external load, and the oil return port 122 is connected to a return oil tank. The external load can be, for example, an actuator, such as a hydraulic cylinder or a motor.
[0044] Valve core drive unit ( Figure 1 (Not shown) is connected to the first end 111 of the valve core 11 and is used to drive the valve core 11 to move between the first position and the second position along the axial direction of the valve body 12, so as to control the opening degree of the oil inlet 121, the oil return port 122 and the working oil port 123.
[0045] Pressure sensor 15 ( Figure 1 (Not shown) Located at the working oil port 123, it is used to detect the current pressure at the working oil port. The displacement sensor 13 includes a contact head 131 and a telescopic contact rod 132. The telescopic contact rod 132 is connected to the first end of the contact head 131, and the second end of the contact head 131 abuts against the second end 112 of the valve core 11 to follow the movement of the valve core 11. The valve core drive unit can be hydraulically controlled, electrically controlled, or mechanically controlled; this utility model does not limit this.
[0046] This invention uses a pressure sensor located at the working oil port and a displacement sensor 13 located at the second end of the valve core 11 to accurately determine the current opening degree of the valve. This helps the controller 17 to compare the target opening degree (or target flow rate) with the current opening degree (or current flow rate) and dynamically adjust the control command to ensure that the valve core 11 is always in the correct position, thereby improving the control accuracy of the hydraulic valve.
[0047] Because the valve core 11 is accurately and controllably positioned, it can achieve precise flow distribution. In practical use, it can precisely control the speed and torque of the valve core drive unit 16, avoiding the large throttling losses and heat losses caused by adjusting speed through throttling or overflow in traditional technologies. This extends the life of hydraulic oil and seals and reduces the load on the cooling system. This invention can also perform fault diagnosis and predictive maintenance of the hydraulic system through precise detection of the valve core position. For example, if the valve core position is inaccurate or stuck, the system can immediately alarm to indicate valve core jamming, thus preventing more serious failures.
[0048] Furthermore, this invention can predict the wear condition of hydraulic valves by monitoring the change trend of valve core response time in real time, thereby achieving predictive maintenance of hydraulic valves.
[0049] In one embodiment, the valve body 12 and valve core 11 are a spool valve type three-position four-way structure. This can be understood as follows: the valve body 12 and valve core 11 adopt a spool valve structure, with the valve core 11 sliding axially within the valve body 12. The oil circuit is opened and closed through the cooperation of the shoulder 113 and the countersunk groove 114 on the valve core 11. The three-position designation means that the valve core 11 has three stable operating positions.
[0050] In one specific embodiment, the working port 123 includes a first port 124 and a second port 125 that are spaced apart along the axial direction of the valve body 12, with an intermediate position between the aforementioned first position and the second position;
[0051] When the valve core moves to the middle position, the oil inlet 121 is connected to the oil return port 122.
[0052] When the valve core moves to the first position, the oil inlet 121 is connected to the first oil port 124, and the oil return port 122 is connected to the second oil port 125.
[0053] When the valve core 11 moves to the second position, the oil inlet 121 is connected to the second oil port 125, and the oil return port 122 is connected to the first oil port 124.
[0054] In one embodiment, the above-mentioned intermediate position can be understood as the normal position, at which time the valve core 11 is centered. The first position can be, for example, the valve core 11 moving to the left to the left position, and the second position can be, for example, the valve core 11 moving to the right to the right position.
[0055] In other alternative embodiments, the valve core 11 can also be connected to each oil port in different positions in different ways as described above. As long as the valve core 11 can control the connection relationship of different oil ports through three stable working positions, it does not deviate from the scope of the present utility model embodiment.
[0056] In a further embodiment, along the radial direction of the valve body 12, the working oil port 123 and the return oil port 122 are arranged opposite to each other, and along the circumferential direction of the valve body 12, the oil inlet 121 is located between the working oil port 123 and the return oil port 122.
[0057] Furthermore, in one embodiment, the hydraulic valve 1 with contact-type valve core position detection further includes a first end cap 141 and a second end cap 142. The first end cap 141 is located at the end of the valve body 12 away from the displacement sensor 13, and the second end cap 142 is located at the other end of the valve body 12. At least a portion of the displacement sensor 13 is located within the second end cap 142. In one embodiment, the displacement sensor 13 is mounted to the second end cap 142 by a sealing mounting nut 133.
[0058] In one exemplary embodiment, the displacement sensor 13 further includes a signal processing box 134 and a terminal block 135. The displacement sensor 13 is electrically connected to the controller 17 via the signal processing box 134 and the terminal block 135. During hydraulic valve assembly, the telescopic contact rod is compressed and fixed to the middle position to measure the displacement of the valve core 11 left and right. After installation, it is fixed with a tightening nut, and the program adjusts the current valve core position to zero. In one embodiment, the displacement sensor 13 is an absolute scale pulse system with a measurement accuracy of 1µm, a resolution of 0.1µm, a sampling period of 1ms, an IP67 housing protection rating, and a contact pressure resistance of 30bar.
[0059] In one embodiment, the outer surface of the valve core 11 needs to be hardened to a hardness of HRC > 40. In another embodiment, the roughness Ra of the end face of the second end 112 of the valve core 11 (or the end face in contact with the sensor) is < 1.6. In another embodiment, the perpendicularity of the end face of the second end 112 of the valve core 11 to the axis of the valve core 11 is less than 0.1.
[0060] Those skilled in the art will understand that the oil inlet 121 can be referred to as the P port, the oil return port 122 can be referred to as the T port, and the working oil port 123 can be referred to as the A / B port. In one example of operation, the P port is connected to the hydraulic pump outlet oil source. The control terminal (handle) issues a command to both ends of the valve core 11. Under the action of the control pressure oil or the mechanical operating lever, the valve core will move to the left or right. At this time, the pressure oil at the P port flows to the actuator through the A / B port, and the return oil flows back to the hydraulic oil tank through the T port. At the same time, when the valve core 11 moves to the left or right, it will push the contact head 131 of the displacement sensor 13, which will drive the telescopic contact rod 132 to move. Because the displacement sensor 13 displays zero when the valve core 11 is in the middle position, when the valve core 11 moves to the left, the telescopic contact rod 132 extends, and the displacement information is displayed as positive. When the valve core 11 moves to the right, the telescopic contact rod 132 retracts, and the displacement information is displayed as negative. Since the displacement sensor 13 has a sampling period of 1ms and a resolution of 0.1um, even the smallest displacement of the valve core 11 can be detected, further improving the accuracy of the valve core 11 displacement detection capability.
[0061] In one embodiment, the displacement of the valve core 11 is detected by a displacement sensor, and the current flow rate of the hydraulic valve is calculated. By comparing the current flow rate with the target flow rate (or the flow rate at the target opening), the position of the valve core 11 can be further adjusted. Each displacement information of the valve core corresponds to a flow area of the valve body. Specifically, the current flow rate of the hydraulic valve is determined according to the following formula:
[0062]
[0063] Where Q represents the current flow rate of the hydraulic valve;
[0064] C is the flow coefficient;
[0065] ρ is the density of the hydraulic oil;
[0066] ΔP represents the pressure difference between the relative pressure between the first oil port and the inlet and the relative pressure between the second oil port and the inlet;
[0067] A represents the flow area of the valve body corresponding to the current displacement information.
[0068] As can be seen, by using the pressure sensors installed at the A / B ports of the valve body and combining them with the displacement information of the valve core, the flow rate at a specific valve opening can be easily calculated according to the valve core flow rate formula. This allows the current position of the valve core to be determined. The controller can then compare the "target position" with the "current position" and dynamically adjust the control commands to ensure that the valve core is always in the correct position.
[0069] The preferred embodiments of this utility model have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of this utility model without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of this utility model through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.
Claims
1. A hydraulic valve for contact-type valve core position detection, characterized in that, It includes the valve core, valve body, pressure sensor, displacement sensor, valve core drive unit, and controller; The valve body is provided with a valve core hole that extends through it along its axial direction, and the valve core is disposed in the valve core hole; the side wall of the valve body is provided with an oil inlet, an oil return port and a working oil port that extend through it along its radial direction; the oil inlet is connected to an oil source, the working oil port is connected to the inlet of an external load, and the oil return port is connected to an oil return tank. The valve core drive unit is connected to the first end of the valve core and is used to drive the valve core to move between a first position and a second position along the axial direction of the valve body, so as to control the opening degree of the oil inlet, the oil return port and the working oil port. The pressure sensor is located at the working oil port and the oil inlet, and is used to detect the pressure difference between the working oil port and the oil inlet; The displacement sensor includes a contact head and a telescopic contact rod. The telescopic contact rod is connected to a first end of the contact head, and a second end of the contact head abuts against a second end of the valve core to follow the movement of the valve core. The displacement sensor, the pressure sensor, and the valve core drive unit are all electrically connected to the controller.
2. The hydraulic valve for contact-type valve core position detection according to claim 1, characterized in that, The valve body and valve core are spool valve type three-position four-way structure.
3. The hydraulic valve for contact-type valve core position detection according to claim 2, characterized in that, Along the radial direction of the valve body, the working oil port and the return oil port are arranged opposite to each other, and along the circumferential direction of the valve body, the oil inlet is located between the working oil port and the return oil port.
4. The hydraulic valve for contact-type valve core position detection according to claim 2, characterized in that, The working oil port includes a first oil port and a second oil port that are spaced apart along the axial direction of the valve body, with an intermediate position between the first position and the second position; When the valve core moves to the intermediate position, the oil inlet is connected to the oil return port; When the valve core moves to the first position, the oil inlet is connected to the first oil port, and the oil return port is connected to the second oil port; When the valve core moves to the second position, the oil inlet is connected to the second oil port, and the oil return port is connected to the first oil port.
5. The hydraulic valve for contact-type valve core position detection according to claim 1, characterized in that, It also includes a first end cap and a second end cap, the first end cap being disposed at one end of the valve body away from the displacement sensor, and the second end cap being disposed at the other end of the valve body, with at least a portion of the displacement sensor located inside the second end cap.
6. The hydraulic valve for contact-type valve core position detection according to any one of claims 1 to 5, characterized in that, The outer wall hardness of the valve core is HRC > 40.
7. The hydraulic valve for contact-type valve core position detection according to any one of claims 1 to 5, characterized in that, The surface roughness Ra of the second end of the valve core is less than 1.
6.
8. The hydraulic valve for contact-type valve core position detection according to any one of claims 1 to 5, characterized in that, The perpendicularity between the end face of the second end of the valve core and the axis of the valve core is less than 0.1.