A zero calibration tool and spool zeroing method for spool valve type parts

Abstract

The application provides a zero calibration tool for a sliding valve type part and a spool zero setting method, and belongs to the technical field of spool zero setting. The tool comprises a reference calibration module and a detection clamping module which are detachably connected. The reference calibration module is provided with a containing cavity, a zero standard part, an elastic support part and a limiting plugging part. The zero standard part is provided with a centering cone surface. The detection clamping module comprises a clamping block, a positioning rod and a length detection part. The clamping block is cooperatively installed on the reference calibration module and is provided with a mounting hole. The positioning rod is installed in the mounting hole and is hinged to the clamping block. The lower end of the positioning rod is provided with an outer cone surface. The length detection part is fixedly installed on the clamping block, and a measuring head is in abutment with the side wall of the positioning rod. The zero calibration tool for the sliding valve type part provided by the application simplifies the operation process of zero point calibration, does not need to rely on a process sample to repeatedly test and adjust, can shorten the time consumption of a pre-calibration process, and improves the operation efficiency.

Description

Technical Field

[0001] This application belongs to the field of valve core zeroing technology, and more specifically, it relates to a zero-position calibration fixture and valve core zeroing method for slide valve parts. Background Technology

[0002] Precision spool valves are core functional components in hydraulic servo control systems. The zero position of the valve core relative to the valve sleeve directly determines the flow characteristics, control accuracy, and response performance of the spool valve. Therefore, zero-position calibration is an indispensable key process in the assembly and debugging of spool valves. The accuracy and stability of zero-position calibration are the core prerequisites for ensuring consistent product performance.

[0003] Currently, the industry commonly uses a process sample comparison method to calibrate the zero position of slide valves. The specific implementation is as follows: a process sample with the same structure as a qualified product is prepared in advance as a standard reference. The process sample is installed inside a test block, and then a detection component with a positioning rod is assembled with the test block, so that the positioning rod is inserted into the corresponding positioning structure of the process sample. Through repeated testing and fine-tuning of the sample's state, after confirming that the process sample is at the standard zero position, the length gauge reading on the detection component is set to zero. This length gauge's zero position is used as the judgment benchmark for subsequent batch product zero position testing. To prevent the length gauge from losing its calibration zero point due to power failure, the length gauge must always be fixed in the same installation position and continuously powered during subsequent product testing.

[0004] However, this zero-point calibration operation is cumbersome and inefficient. Each time a standard zero point is established, repeated testing and adjustments to the process sample are required. The pre-calibration process is lengthy, tedious, and time-consuming, making it difficult to meet the high-efficiency production and debugging needs of large-volume slide valve products. Furthermore, the zero point is entirely dependent on the power supply and fixed installation position of the length gauge. In the event of an unexpected power outage or equipment relocation, the calibrated zero point will be lost, requiring the process sample to be disassembled and reassembled, and the calibration process to be completely repeated, frequently interrupting production and increasing downtime and maintenance costs. Moreover, with repeated use, the spring force of the process sample will decrease, resulting in inherent errors in the sample itself. Therefore, when calibrating the zero point using the process sample, the zero point will not be an absolute zero. Summary of the Invention

[0005] The purpose of this application is to provide a zero-point calibration fixture and valve core zeroing method for slide valve parts, so as to solve the technical problems of cumbersome zero-point calibration operation and low operation efficiency in the prior art.

[0006] To achieve the above objectives, the technical solution adopted in this application is: to provide a zero-position calibration fixture for slide valve parts, including a detachably connected reference calibration module and a detection clamping module; The reference calibration module is provided with a receiving cavity and a zero-position standard component, an elastic support component, and a limiting and sealing component arranged sequentially from top to bottom; the zero-position standard component is provided with a centering cone surface; The detection clamping module includes a clamping block, a positioning rod, and a length detection component. The clamping block is fitted onto the reference calibration module and has a mounting hole corresponding to the receiving cavity. The positioning rod is installed in the mounting hole and hinged to the clamping block to swing left and right. The lower end of the positioning rod has an outer conical surface adapted to the centering conical surface. The length detection component is fixedly installed on the clamping block, and the probe abuts against the side wall of the positioning rod to collect the swing displacement of the positioning rod. Wherein, the outer conical surface at the lower end of the positioning rod abuts against the centering conical surface of the zero-position standard component, and the elastic support pushes the zero-position standard component under the action of the limiting and sealing component, so that the positioning rod automatically maintains a vertical centering state to complete the zero-point calibration.

[0007] In one possible implementation, the reference calibration module has an installation groove at its upper end, and the receiving cavity is formed on the bottom surface of the installation groove; the clamping block is fitted and installed in the installation groove.

[0008] In one possible implementation, the bottom surface of the mounting groove is provided with a plurality of connecting holes arranged around the receiving cavity, and the clamping block is provided with a plurality of communicating holes, and the communicating holes correspond one-to-one with the connecting holes; the clamping block and the reference calibration module are fixedly connected by fasteners passing through the communicating holes and the connecting holes.

[0009] In one possible implementation, a positioning pin is provided on the bottom surface of the mounting groove, and a pin hole adapted to the positioning pin is opened on the lower end surface of the clamping block.

[0010] In one possible implementation, the clamping block is provided with an upwardly extending mounting plate, and the mounting plate has horizontally arranged fixing holes. The length detection element passes through the fixing holes, and the probe extends toward the positioning rod.

[0011] In one possible implementation, an internal thread section is provided on the lower inner wall of the receiving cavity, and an external thread section is provided on the outer wall of the limiting and sealing member to cooperate with the internal thread section. The limiting and sealing member is screwed to apply force to the elastic support member and the zero-position standard member.

[0012] In one possible implementation, the positioning rod is provided with a rotating hole located in the mounting hole, the clamping block is provided with an assembly hole arranged coaxially with the rotating hole and a connecting shaft passing through the assembly hole and the rotating hole, the connecting shaft is rotatably connected to the positioning rod, and the axial direction of the connecting shaft is perpendicular to the length direction of the length detection component; the positioning rod is provided with a contact plane corresponding to the length detection component.

[0013] One possible implementation also includes: The test support block has a mounting cavity for accommodating the valve core and sleeve assembly to be tested, and the test support block has a mounting surface for mounting the clamping block body, and the mounting surface has a through hole communicating with the mounting cavity.

[0014] The beneficial effects of the zero-position calibration fixture for slide valve parts provided in this application are as follows: Compared with the prior art, the zero-position calibration fixture for slide valve parts in this application adopts a separate design of a detachable reference calibration module and a detection clamping module, and achieves automatic centering of the positioning rod through mechanical conical surface cooperation, thereby establishing a stable standard zero position.

[0015] The reference calibration module is equipped with a receiving cavity, in which a zero-position standard component, an elastic support component, and a limiting and sealing component are arranged sequentially from top to bottom. The zero-position standard component has a centering conical surface machined on it, and the limiting and sealing component can axially limit the elastic support component and the zero-position standard component. The detection clamping module consists of a clamping block, a positioning rod, and a length detection component. The clamping block has a mounting hole corresponding to the receiving cavity. The positioning rod is installed in the mounting hole and is hinged to the clamping block, allowing it to swing slightly in the left and right directions. The lower end of the positioning rod has an outer conical surface that matches the centering conical surface. The length detection component is fixedly installed on the clamping block, and its probe abuts against the side wall of the positioning rod, which can collect the displacement generated by the swing of the positioning rod in real time.

[0016] In practical applications, the tooling assembly and zero-point calibration are completed first. The zero-position standard part, elastic support part, and limit sealing part are then sequentially installed into the receiving cavity of the reference calibration module. The clamping block with the assembled positioning rod and length detection part is then installed onto the reference calibration module. The limit sealing part is adjusted so that it acts on the elastic support part, and the elastic support part pushes the zero-position standard part upward, so that the centering cone surface and the outer cone surface at the lower end of the positioning rod are tightly fitted. Under the action of the cone surface, the positioning rod automatically maintains a vertical centering state. At this time, the reading of the length detection part is set to zero, and the calibration of the standard zero position is completed.

[0017] After calibration, the clamping block and length measuring piece can be removed from the reference calibration module and transferred to the test support block containing the valve core and valve sleeve assembly to be adjusted. The lower end of the positioning rod is inserted into the groove of the valve core. The offset reading of the length measuring piece is observed. Based on the offset direction of the reading, the thickness of the adjusting shims on the adjusting parts at both ends of the valve core is changed to compensate for the offset until the reading of the length measuring piece returns to zero. This indicates that the valve core is at the geometric center of the valve sleeve, and the zero-position adjustment is completed.

[0018] This approach simplifies the zero-point calibration process by utilizing a modular design and a self-centering conical mechanical reference structure. It eliminates the need for repeated testing and adjustments using process samples, reducing the time required for pre-calibration and adapting to the production and debugging needs of batch slide valve products. It also avoids errors caused by spring force attenuation due to prolonged use of process samples. The standard zero point is established through the mechanical fit of the tooling, no longer entirely dependent on the continuous power supply and fixed installation position of the length gauge. This reduces the impact of unexpected power outages and equipment relocation on zero-point stability, minimizes recalibration work due to zero-point loss, helps stabilize production cycles, and reduces maintenance costs and time losses during production.

[0019] Another objective of this application is to provide a valve core zeroing method, employing any of the above-mentioned zero-position calibration fixtures for slide valve-type parts, including: S1: The zero-position standard component, the elastic support component, and the limiting and sealing component are installed on the reference calibration module; the positioning rod and the length detection component are installed on the clamping block; and the clamping block is assembled on the reference calibration module. S2: Manipulate the movement of the limiting and sealing component to compress the elastic support component. The elastic support component pushes the zero-position standard component upward, so that the centering cone surface and the outer cone surface of the positioning rod are fitted together and installed to ensure that the positioning rod automatically maintains a vertical state. Set the reading of the length detection component to zero and complete the standard zero-position calibration. S3: Install the valve core and valve sleeve assembly to be tested on the test support block. The adjusting parts at both ends of the valve core and valve sleeve assembly to be tested are installed at both ends of the test support block, and the slots on the valve core correspond to the through holes. S4: Disassemble the clamping block and fix it on the mounting surface of the test bearing block. The lower end of the positioning rod passes through the through hole and enters the slot of the valve core. S5: Observe the offset reading of the length detection component, and compensate for the offset by changing the thickness of the adjusting shims on the two adjusting components according to the offset direction of the reading, until the length detection component reading returns to zero, the valve core is at the geometric center of the valve sleeve, and the zero-position adjustment of the valve core and valve sleeve assembly to be adjusted is completed.

[0020] In one possible implementation, the method further includes: S6: re-inspecting the valve core, manipulating the adjusting component to make bidirectional linear movement with the same amplitude, and observing the offset reading of the length detection component; if the offset readings are inconsistent, then readjusting the thickness of the adjusting shim.

[0021] The valve core zeroing method provided in this application first performs a tooling pre-assembly step. The operator first assembles the zero-position standard part, elastic support part and limit sealing part into the corresponding structure of the reference calibration module in sequence to complete the pre-assembly of the reference side components. At the same time, the positioning rod is hinged and installed in the mounting hole of the clamping block, and the length detection part is fixed on the corresponding mounting position of the clamping block to complete the pre-assembly of the detection clamping module.

[0022] Next, the pre-assembled clamping block is aligned and assembled onto the reference calibration module, so that the two modules form a stable mating connection. Then, the standard zero-position calibration is performed. The operator manipulates the limiting and sealing component to move axially to compress the elastic support component, so that the elastic support component generates an upward pushing force and acts on the zero-position standard component, pushing the zero-position standard component to rise axially along the receiving cavity until the centering cone surface at the upper end of the zero-position standard component is tightly fitted with the outer cone surface at the lower end of the positioning rod. Under the guiding action of the cone surface mating, the positioning rod automatically adjusts its posture and maintains a vertical state. After confirming that the posture of the positioning rod is stable, the reading of the length measuring component is set to zero, thus completing the standard zero-position calibration process.

[0023] After calibration, the workpiece is pre-assembled. The operator inserts the valve core and sleeve assembly to be tested into the mounting cavity of the test support block. The adjusting parts at both ends of the valve core and sleeve assembly are installed at the two ends of the test support block. At the same time, the position of the valve core is adjusted so that the groove in the middle of the valve core is aligned with the through hole on the mounting surface of the test support block, ensuring that the positioning rod can be smoothly inserted later. Then, the detection module is transferred. The operator removes the clamping block, along with the positioning rod and length detection piece, from the benchmark calibration module. The clamping block is then aligned and fixed on the mounting surface of the test support block. During the installation, the lower end of the positioning rod is ensured to accurately pass through the through hole and enter the groove in the middle of the valve core, so that the axial displacement of the valve core can drive the positioning rod to swing synchronously through the groove.

[0024] Finally, the zero-position adjustment process is performed. The operator observes the offset reading displayed on the length measuring device, determines the offset direction of the valve core relative to the valve sleeve based on the offset direction of the reading, and compensates for the offset by changing the thickness of the adjusting shims on the adjusting parts at both ends. The change in shim thickness pushes the valve core to move axially, gradually correcting the offset of the valve core. The shim configuration is repeatedly fine-tuned until the reading of the length measuring device returns to zero, which means that the valve core is at the geometric center of the valve sleeve. The zero-position adjustment of the valve core and valve sleeve assembly is then completed.

[0025] This approach, relying on the modular structure of the tooling and the mechanical centering reference, eliminates the need for repeated testing and adjustments using process samples. It simplifies the zero-point calibration process, shortens the time required for pre-calibration, and adapts to the production and debugging needs of batch slide valve products. It also avoids errors caused by the attenuation of spring force due to prolonged use of process samples. The standard zero position is established through a conical surface fit mechanical structure, and the zero-point state is retained based on the overall assembly state of the detection clamping module. It no longer relies entirely on the continuous power supply and fixed installation position of the length detection component, which reduces the impact of unexpected power outages and equipment relocation on zero-point stability. It also reduces re-calibration work caused by zero-point loss, helps to stabilize the production cycle, and reduces maintenance costs and time losses during the production process. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the zero-position calibration fixture for slide valve parts provided in an embodiment of this application; Figure 2 A cross-sectional view of a zero-position calibration fixture for slide valve-type parts provided in an embodiment of this application; Figure 3 This is a schematic diagram of the structure of the reference calibration module provided in the embodiments of this application; Figure 4 This is a schematic diagram of the structure of the zero-position standard component provided in the embodiments of this application; Figure 5 This is a schematic diagram of the structure of the clamping block provided in the embodiments of this application; Figure 6 This is a schematic diagram of the positioning rod provided in an embodiment of this application; Figure 7 A schematic diagram showing the connection between the test support block and the valve core and sleeve assembly to be tested, provided in an embodiment of this application; Figure 8 A schematic diagram showing the connection of the detection clamping module, the test support block, and the valve core and sleeve assembly to be debugged provided in the embodiments of this application; Figure 9 for Figure 8 A partial schematic diagram.

[0028] The following are the labeling elements in the figure: 10. Reference calibration module; 11. Receiving cavity; 12. Zero-position standard component; 13. Elastic support component; 14. Limiting and sealing component; 15. Centering cone surface; 16. Mounting groove; 17. Connecting hole; 20. Detection clamping module; 21. Clamping block; 211. Assembly hole; 22. Positioning rod; 221. Connecting shaft; 222. Contact plane; 223. Rotation hole; 23. Length detection component; 24. Mounting hole; 25. Outer cone surface; 26. Connecting hole; 27. Fastener; 28. Mounting plate; 29. ​​Fixing hole; 30. Test bearing block; 31. Mounting cavity; 32. Mounting surface; 33. Through hole; 40. Valve core and sleeve assembly to be debugged; 41. Valve core; 411. Slot; 42. Valve sleeve; 43. Adjusting component; 44. Spring seat; 45. Adjusting shim; 46. Center; 47. Spring. Detailed Implementation

[0029] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0030] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0031] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application 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 this application.

[0032] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0033] Please see Figures 1 to 9 The zero-position calibration fixture for slide valve parts provided in this application will now be described. A zero-position calibration fixture for slide valve parts includes a detachably connected reference calibration module 10 and a detection clamping module 20. The reference calibration module 10 is provided with a receiving cavity 11 and a zero-position standard component 12, an elastic support component 13 and a limiting and sealing component 14 arranged sequentially from top to bottom; the zero-position standard component 12 is provided with a centering cone surface 15; The detection clamping module 20 includes a clamping block 21, a positioning rod 22, and a length detection component 23. The clamping block 21 is fitted onto the reference calibration module 10 and has a mounting hole 24 corresponding to the receiving cavity 11. The positioning rod 22 is installed in the mounting hole 24 and is hinged to the clamping block 21, allowing it to swing left and right. The lower end of the positioning rod 22 has an outer conical surface 25 that matches the centering conical surface 15. The length detection component 23 is fixedly installed on the clamping block 21, and the probe abuts against the side wall of the positioning rod 22 to collect the swing displacement of the positioning rod 22. The outer conical surface 25 at the lower end of the positioning rod 22 abuts against the centering conical surface 15 of the zero-position standard part 12. The elastic support part 13 pushes the zero-position standard part 12 under the action of the limiting and sealing part 14, so that the positioning rod 22 automatically maintains a vertical centering state to complete the zero-point calibration.

[0034] The zero-position calibration fixture for slide valve parts provided in this application adopts a split design of a detachable reference calibration module 10 and a detection clamping module 20, and achieves automatic centering of the positioning rod 22 through mechanical conical surface cooperation, thereby establishing a stable standard zero position.

[0035] The reference calibration module 10 is equipped with a receiving cavity 11. Inside the receiving cavity 11, a zero-position standard component 12, an elastic support component 13, and a limiting and sealing component 14 are arranged sequentially from top to bottom. The zero-position standard component 12 is machined with a centering conical surface 15. The limiting and sealing component 14 can axially limit the elastic support component 13 and the zero-position standard component 12. The detection clamping module 20 is composed of a clamping block 21, a positioning rod 22, and a length detection component 23. The clamping block 21 is provided with a mounting hole 24 corresponding to the receiving cavity 11. The positioning rod 22 is installed in the mounting hole 24 and is hinged to the clamping block 21, allowing it to swing slightly in the left and right directions. The lower end of the positioning rod 22 is machined with an outer conical surface 25 that matches the centering conical surface 15. The length detection component 23 is fixedly installed on the clamping block 21, and its probe abuts against the side wall of the positioning rod 22, allowing it to collect the displacement generated by the swing of the positioning rod 22 in real time.

[0036] In practical applications, the tooling assembly and zero-point calibration are completed first. The zero-position standard part 12, the elastic support part 13, and the limiting and sealing part 14 are sequentially installed into the receiving cavity 11 of the reference calibration module 10. Then, the clamping block 21 with the positioning rod 22 and the length detection part 23 assembled is installed on the reference calibration module 10. The limiting and sealing part 14 is adjusted so that it acts on the elastic support part 13. The elastic support part 13 pushes the zero-position standard part 12 upward so that the centering cone surface 15 and the outer cone surface 25 at the lower end of the positioning rod 22 are tightly fitted. Under the action of the cone surface, the positioning rod 22 automatically maintains a vertical centering state. At this time, the reading of the length detection part 23 is set to zero, and the calibration of the standard zero position is completed.

[0037] After calibration, the clamping block 21 and the length measuring piece 23 can be removed from the reference calibration module 10 and transferred to the test support block 30 containing the valve core and valve sleeve assembly 40 to be adjusted for installation. The lower end of the positioning rod 22 is inserted into the slot 411 of the valve core 41. The offset reading of the length measuring piece 23 is observed. Based on the offset direction of the reading, the thickness of the adjusting shims 45 on the adjusting parts 43 at both ends of the valve core 41 is changed to compensate for the offset until the reading of the length measuring piece 23 returns to zero, which means that the valve core 41 is at the geometric center of the valve sleeve 42, and the zero-position adjustment is completed.

[0038] This approach simplifies the zero-point calibration process by utilizing a modular design and a self-centering conical mechanical reference structure. It eliminates the need for repeated testing and adjustments using process samples, reducing the time required for pre-calibration and adapting to the production and debugging needs of batch slide valve products. It also avoids errors caused by spring force attenuation due to prolonged use of process samples. The standard zero point is established using the mechanical fit of the tooling, no longer entirely dependent on the continuous power supply and fixed installation position of the length gauge. This reduces the impact of unexpected power outages and equipment relocation on zero-point stability, minimizes repetitive calibration work due to zero-point loss, helps stabilize production cycles, and reduces maintenance costs and time losses during production.

[0039] Please see Figures 1 to 3As a specific embodiment of the zero-point calibration fixture for slide valve parts provided in this application, a recessed mounting groove 16 is machined at the upper end of the reference calibration module 10. The receiving cavity 11 is directly opened at the center of the bottom of the mounting groove 16. The outer dimensions of the clamping block 21 are adapted to the inner dimensions of the mounting groove 16. When assembled, the clamping block 21 can be embedded into the mounting groove 16 as a whole, forming a fitting relationship. When assembling the fixture for zero-point calibration, the zero-point standard part 12, the elastic support part 13, and the limiting and sealing part 14 are first installed into the receiving cavity 11 in sequence. Then, the pre-assembled clamping block 21 is aligned with the opening direction of the mounting groove 16 and smoothly placed in. The inner sidewall of the mounting groove 16 forms a circumferential limit on the clamping block 21. No additional fine alignment is required to keep the mounting hole 24 of the clamping block 21 coaxial with the receiving cavity 11 of the reference calibration module 10.

[0040] The interlocking mounting slot 16 structure allows for rapid initial positioning of the two main modules during assembly, reducing the difficulty of alignment operations and minimizing positional deviations during assembly. Simultaneously, the sidewalls of the mounting slot 16 provide lateral constraints on the clamping block 21, limiting its horizontal movement during calibration and debugging, improving the overall assembly stability of the tooling, and ensuring the accuracy of zero-point calibration and displacement detection.

[0041] Please see Figures 1 to 3 , Figure 5 As a specific embodiment of the zero-position calibration fixture for slide valve parts provided in this application, the bottom surface of the mounting groove 16 is provided with a plurality of connecting holes 17 arranged around the receiving cavity 11, and the clamping block 21 is provided with a plurality of communicating holes 26, and the communicating holes 26 correspond one-to-one with the connecting holes 17; the clamping block 21 and the reference calibration module 10 are fixedly connected by fasteners 27 passing through the communicating holes 26 and the connecting holes 17.

[0042] Multiple connecting holes 17 are evenly arranged around the central receiving cavity 11 on the bottom surface of the mounting groove 16, corresponding to the connecting holes 26 on the clamping block 21 in terms of position and number. During assembly, after the clamping block 21 is embedded into the mounting groove 16 and initially positioned, the fasteners 27 are passed through the connecting holes 26 in sequence and screwed into the corresponding connecting holes 17 to achieve a tight connection between the reference calibration module 10 and the clamping block 21. During operation, the fasteners 27 can be tightened in a diagonal order to ensure that the clamping block 21 is subjected to uniform force and that the mating surfaces are in close contact.

[0043] The use of multiple fasteners 27 enhances the connection between the two modules, preventing loosening or misalignment during calibration or transfer and ensuring the stability of the zero-point calibration state. Simultaneously, the evenly distributed connection holes 17 around the receiving cavity 11 ensure that the connection force is evenly distributed around the centering structure, reducing tilting of the clamping block 21 due to uneven force distribution and further guaranteeing the accuracy of the vertical centering of the positioning rod 22.

[0044] Preferably, the connecting hole 17 is a screw hole, and the fastener 27 is a bolt.

[0045] As a specific embodiment of the zero-position calibration fixture for slide valve parts provided in this application, a protruding locating pin is provided on the bottom surface of the mounting groove 16, and a pin hole adapted to the size and position of the locating pin is machined on the lower end surface of the clamping block 21. During assembly, the pin hole of the clamping block 21 is first aligned with the locating pin, and then the clamping block 21 is lowered vertically so that the locating pin is embedded in the pin hole, thus completing the precise alignment of the two modules. Then, the fastener 27 is tightened. The number of locating pins can be set to two or more according to the fixture size, forming a positioning system that constrains displacement and rotation in the constrained plane.

[0046] The fit between the locating pin and the pin hole is a precision centering and positioning structure, which can effectively improve the alignment accuracy of the reference calibration module 10 and the detection clamping module 20, avoid positional deviations caused by the fit clearance of the mounting groove 16, ensure the coaxiality of the receiving cavity 11 and the mounting hole 24, and thus ensure the centering accuracy of the conical fit of the locating rod 22. At the same time, this structure can achieve pre-positioning before the fastener 27 is tightened, reducing the alignment difficulty of the assembly operation and shortening the time spent on tooling assembly.

[0047] Please see Figure 1 , Figure 2 and Figure 5 As a specific embodiment of the zero-position calibration fixture for slide valve parts provided in this application, an upwardly extending mounting plate 28 is provided on the side of the clamping block 21. The mounting plate 28 has horizontally arranged fixing holes 29 machined on it, and the axis of the fixing holes 29 is parallel to the swing plane of the positioning rod 22. When assembling the length detection component 23, the main body of the length detection component 23 is inserted into the fixing hole 29, and the extension length of the probe is adjusted so that the end of the probe is in contact with the side wall of the positioning rod 22. After confirming that the position is appropriate, the length detection component 23 can be locked to complete the assembly of the detection unit.

[0048] Mounting plate 28 provides a stable mounting carrier for length detection component 23, avoiding interference with the swing space of positioning rod 22 caused by opening holes in the main body of clamping block 21. Horizontally arranged fixing holes 29 ensure that length detection component 23 is installed horizontally, keeping the detection direction of the probe consistent with the swing displacement direction of positioning rod 22, reducing component errors in the detection direction, and improving the accuracy of displacement acquisition. Simultaneously, this structure facilitates the disassembly, assembly, and position adjustment of length detection component 23, adapting to detection devices of different specifications.

[0049] Preferably, the mounting plate 28 has a clamp structure, and the fixing hole 29 is provided on the clamp structure, so that the length measuring piece 23 can be stably installed on the mounting plate 28.

[0050] Please see Figure 1 , Figure 2 and Figure 5 As a specific embodiment of the zero-position calibration fixture for slide valve parts provided in this application, an internal thread section is provided on the lower inner wall of the receiving cavity 11, and an external thread section is provided on the outer wall of the limiting seal 14 to cooperate with the internal thread section. The limiting seal 14 is screwed on to apply force to the elastic support 13 and the zero-position standard 12. During assembly, the zero-position standard 12 and the elastic support 13 are first inserted into the upper end of the receiving cavity 11 in sequence, and then the limiting seal 14 is screwed in from the lower end of the receiving cavity 11. By screwing on the limiting seal 14, its axial position in the receiving cavity 11 is adjusted, thereby changing the compression of the elastic support 13 and applying different sizes of upward pushing force to the zero-position standard 12 to ensure that the centering cone surface 15 and the outer cone surface 25 of the positioning rod 22 are tightly fitted.

[0051] The threaded adjustment method allows for precise control of the preload of the elastic support 13, ensuring that the tightness of the conical surface fit remains within a reasonable range. Simultaneously, the threaded connection possesses reliable self-locking performance; after calibration, the limiting and sealing component 14 will not loosen or shift on its own, stably maintaining the pushing state and ensuring the long-term stability of the mechanical reference.

[0052] Please see Figures 1 to 6 As a specific embodiment of the zero-position calibration fixture for slide valve parts provided in this application, a transversely penetrating rotating hole 223 is machined on the upper part of the positioning rod 22. Correspondingly, assembly holes 211 coaxial with the rotating hole 223 are opened on the two side walls of the clamping block 21. The connecting shaft 221 passes through the assembly hole 211 and the rotating hole 223, so that the positioning rod 22 is rotatably connected to the clamping block 21 with the connecting shaft 221 as the pivot, and can swing left and right along a plane perpendicular to the axis of the connecting shaft 221. The axial direction of the connecting shaft 221 is perpendicular to the length direction of the length detection component 23. A flat contact surface 222 is machined on the side of the positioning rod 22 facing the length detection component 23, and the probe of the length detection component 23 abuts against the contact surface 222.

[0053] The fit between the connecting shaft 221 and the rotating hole 223 ensures the smoothness and rotational accuracy of the positioning rod 22's swing, reduces jamming and radial movement during the swing process, and improves the accuracy of displacement transmission. Setting the axis of the connecting shaft 221 perpendicular to the length direction of the length sensing element 23 ensures that the swing direction of the positioning rod 22 precisely corresponds to the detection direction of the probe, avoiding swing components perpendicular to the detection direction. The contact plane 222 increases the contact area of ​​the probe, reducing wear and detection errors caused by point contact, and ensuring the stability and repeatability of displacement acquisition.

[0054] Please see Figure 1 , Figure 2 and Figure 7 As a specific embodiment of the zero-point calibration fixture for spool valve parts provided in this application, an independent test support block 30 is provided. The test support block 30 has an axially penetrating mounting cavity 31 inside to accommodate and fix the valve core 41 and valve sleeve 42 assembly to be debugged. The upper end surface of the test support block 30 is a flat mounting surface 32, and a through hole 33 communicating with the internal mounting cavity 31 is provided on the mounting surface 32. The position of the through hole 33 corresponds to the slot 411 in the middle of the valve core 41. After the zero-point calibration is completed, the clamping block 21 is removed from the reference calibration module 10, aligned with the position of the through hole 33 on the mounting surface 32, and fixedly installed on the test support block 30. The lower end of the positioning rod 22 can then pass through the through hole 33 and extend into the slot 411 of the valve core 41 to carry out subsequent zeroing operations.

[0055] The independently designed test support block 30 can serve as a dedicated clamping carrier for the workpiece, forming a complete zeroing tooling system with the reference calibration module 10 and the detection clamping module 20. This ensures the consistency of the workpiece clamping state and improves the efficiency of batch debugging. The through hole 33 provides clearance and guidance for the positioning rod 22, allowing it to accurately extend into the valve core 41 slot 411, ensuring the accuracy of displacement transmission. Simultaneously, this structure enables the detection clamping module 20 to be quickly transferred between the reference calibration module 10 and the test support block 30, achieving the effect of one-time calibration and multiple reuses, simplifying the pre-process of product debugging.

[0056] Please see Figures 1 to 9 This application also provides a valve core zeroing method, which employs any of the above-mentioned zero-position calibration fixtures for slide valve parts, including: S1: Install the zero-position standard part 12, elastic support part 13 and limit sealing part 14 on the reference calibration module 10, install the positioning rod 22 and length detection part 23 on the clamping block 21, and assemble the clamping block 21 on the reference calibration module 10. S2: Move the limit sealing component 14 to compress the elastic support component 13. The elastic support component 13 pushes the zero standard component 12 upward, so that the centering cone surface 15 and the outer cone surface 25 of the positioning rod 22 fit together, ensuring that the positioning rod 22 automatically maintains a vertical state, and sets the reading of the length detection component 23 to zero, thus completing the standard zero position calibration. S3: Install the valve core and sleeve assembly 40 to be tested on the test support block 30. The adjusting parts 43 at both ends of the valve core and sleeve assembly 40 to be tested are installed at both ends of the test support block 30, and the slot 411 on the valve core 41 corresponds to the through hole 33. S4: Disassemble the clamping block 21 and fix it on the mounting surface 32 of the test bearing block 30. The lower end of the positioning rod 22 passes through the through hole 33 and enters the slot 411 of the valve core 41. S5: Observe the offset reading of the length detection piece 23, and according to the offset direction of the reading, compensate for the offset by changing the thickness of the adjusting shim 45 on the two adjusting parts 43 until the reading of the length detection piece 23 returns to zero, the valve core 41 is at the geometric center of the valve sleeve 42, and the zero-position adjustment of the valve core and valve sleeve assembly 40 is completed.

[0057] The valve core zeroing method provided in this application first performs a tooling pre-assembly step. The operator first assembles the zero-position standard part 12, the elastic support part 13 and the limit sealing part 14 into the corresponding structure of the reference calibration module 10 in sequence to complete the pre-assembly of the reference side components. At the same time, the positioning rod 22 is hinged and installed in the mounting hole 24 of the clamping block 21, and the length detection part 23 is fixed in the corresponding mounting position of the clamping block 21 to complete the pre-assembly of the detection clamping module 20.

[0058] Next, the pre-assembled clamping block 21 is aligned and assembled onto the reference calibration module 10, so that the two modules form a stable mating connection. Then, the standard zero position calibration is performed. The operator manipulates the limiting sealing part 14 to move axially to compress the elastic support part 13, so that the elastic support part 13 generates an upward pushing force and acts on the zero position standard part 12, pushing the zero position standard part 12 to rise axially along the receiving cavity 11 until the centering cone surface 15 at the upper end of the zero position standard part 12 is tightly fitted with the outer cone surface 25 at the lower end of the positioning rod 22. Under the guiding action of the cone surface mating, the positioning rod 22 automatically adjusts its posture and maintains a vertical state. After confirming that the posture of the positioning rod 22 is stable, the reading of the length detection part 23 is set to zero, thus completing the standard zero position calibration process.

[0059] After calibration, the workpiece is pre-assembled. The operator inserts the valve core and sleeve assembly 40 to be tested into the mounting cavity 31 of the test support block 30. The adjusting parts 43 at both ends of the valve core 41 and sleeve 42 assembly are installed at the two ends of the test support block 30. At the same time, the position of the valve core 41 is adjusted so that the slot 411 in the middle of the valve core 41 is aligned with the through hole 33 on the mounting surface 32 of the test support block 30, ensuring that the positioning rod 22 can be smoothly inserted. Then, the detection module is transferred. The operator removes the clamping block 21 together with the positioning rod 22 and the length detection part 23 from the reference calibration module 10. Then, the clamping block 21 is aligned and fixedly installed on the mounting surface 32 of the test support block 30. During the installation, the lower end of the positioning rod 22 is ensured to accurately pass through the through hole 33 and enter the slot 411 in the middle of the valve core 41, so that the axial displacement of the valve core 41 can drive the positioning rod 22 to swing synchronously through the slot 411.

[0060] Finally, the zero-position adjustment process is performed. The operator observes the offset reading displayed by the length detection component 23, and judges the offset position of the valve core 41 relative to the valve sleeve 42 based on the offset direction of the reading. The offset is compensated by changing the thickness of the adjusting shims 45 on the adjusting components 43 at both ends. The change in shim thickness pushes the valve core 41 to move axially, gradually correcting the offset of the valve core 41. The shim configuration is repeatedly fine-tuned until the reading of the length detection component 23 returns to zero, which means that the valve core 41 is at the geometric center position of the valve sleeve 42. The zero-position adjustment of the valve core and valve sleeve assembly 40 is then completed.

[0061] This approach, relying on the modular structure of the tooling and the mechanical centering reference, eliminates the need for repeated testing and adjustments using process samples. It simplifies the zero-point calibration process, shortens the time required for pre-calibration, and adapts to the production and debugging needs of batch slide valve products. It also avoids errors caused by the attenuation of spring force due to prolonged use of process samples. The standard zero position is established through a conical surface fit mechanical structure, and the zero-point state is retained based on the overall assembly state of the detection clamping module 20. It no longer relies entirely on the continuous power supply and fixed installation position of the length detection component 23. This reduces the impact of unexpected power outages and equipment relocation on zero-point stability, minimizes repetitive calibration work caused by zero-point loss, helps stabilize the production cycle, and reduces maintenance costs and time losses during the production process.

[0062] Please see Figure 8 and Figure 9As a specific implementation of the valve core zeroing method provided in this application, it is executed after the initial adjustment and zeroing is completed in S5, and is used to verify the symmetrical accuracy of the zero position. During operation, the operator first confirms that the valve core 41 is in the initial zero position after adjustment and that the length detection element 23 reading is stable at zero. Then, the operator manipulates the adjusting component 43 on one side of the valve core 41 to push the valve core 41 axially to move it to one side by a preset fixed stroke. After the valve core 41 stabilizes, the operator reads and records the unilateral offset reading corresponding to the length detection element 23. The operator then manipulates the adjusting component 43 to return the valve core 41 to the zero position. After confirming that the reading is zero, the operator manipulates the adjusting component 43 on the other side to push the valve core 41 to move in the opposite direction with the same stroke. After stabilization, the operator reads and records the offset reading on the other side. After completing the bidirectional test, the operator compares the two recorded offset readings. If there is a difference between the two values, it means that the current zero position is not at the true geometric center of the valve core 41. The operator needs to readjust the configuration of the adjusting shims 45 at both ends and perform the zeroing operation again until the offset reading of the length detection element 23 is consistent under the same bidirectional amplitude movement.

[0063] Adding this re-inspection process allows for symmetrical verification of the zeroing results after static zeroing, overcoming the limitations of determining the zero position solely based on a single-sided static reading. It can identify false zero position issues caused by factors such as machining deviations in the valve core 41 slot 411, the fit clearance of the positioning rod 22, and part form and position tolerances. This ensures that the final zero position corresponds to the true geometric center of the valve core 41 and the valve sleeve 42, guaranteeing symmetrical and consistent displacement and flow characteristics of the spool valve during bidirectional operation, and improving the control accuracy and performance consistency of the product.

[0064] Meanwhile, this re-inspection process requires no additional testing fixtures and can be completed using the existing zeroing fixtures and adjusting component 43, making the operation simple and easy to execute. Specifically, the adjusting component 43 uses a screw plug and is equipped with a spring seat 44 and a spring 47, while the valve core 41 is equipped with a tip 46 that acts on the spring seat 44. The screw plug serves a fastening function; after tightening, it ensures that the end face of the screw plug is tightly pressed against the valve sleeve, thus acting as a limit. The spring force of the spring 47 is increased by replacing the adjusting shims 45 with shims of different thicknesses.

[0065] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A zero-position calibration fixture for slide valve-type parts, characterized in that, Includes a detachable reference calibration module and a test clamping module; The reference calibration module is provided with a receiving cavity and a zero-position standard component, an elastic support component, and a limiting and sealing component arranged sequentially from top to bottom; the zero-position standard component is provided with a centering cone surface; The detection clamping module includes a clamping block, a positioning rod, and a length detection component. The clamping block is fitted onto the reference calibration module and has a mounting hole corresponding to the receiving cavity. The positioning rod is installed in the mounting hole and hinged to the clamping block to swing left and right. The lower end of the positioning rod has an outer conical surface adapted to the centering conical surface. The length detection component is fixedly installed on the clamping block, and the probe abuts against the side wall of the positioning rod to collect the swing displacement of the positioning rod. Wherein, the outer conical surface at the lower end of the positioning rod abuts against the centering conical surface of the zero-position standard component, and the elastic support pushes the zero-position standard component under the action of the limiting and sealing component, so that the positioning rod automatically maintains a vertical centering state to complete the zero-point calibration.

2. The zero-position calibration fixture for slide valve-type parts as described in claim 1, characterized in that, The reference calibration module has an installation groove at its upper end, and the receiving cavity is located on the bottom surface of the installation groove; the clamping block is fitted and installed in the installation groove.

3. The zero-position calibration fixture for slide valve parts as described in claim 2, characterized in that, The bottom surface of the mounting groove is also provided with a plurality of connecting holes arranged around the receiving cavity, and the clamping block is provided with a plurality of communicating holes, and the communicating holes correspond one-to-one with the connecting holes; the clamping block and the reference calibration module are fixedly connected by fasteners passing through the communicating holes and the connecting holes.

4. The zero-position calibration fixture for slide valve-type parts as described in claim 3, characterized in that, The bottom surface of the mounting groove is also provided with a positioning pin, and the lower end surface of the clamping block is provided with a pin hole that matches the positioning pin.

5. The zero-position calibration fixture for slide valve-type parts as described in claim 1, characterized in that, The clamping block is provided with an upwardly extending mounting plate, and the mounting plate has horizontally arranged fixing holes. The length detection component passes through the fixing holes, and the probe extends toward the positioning rod.

6. The zero-position calibration fixture for slide valve parts as described in claim 1, characterized in that, An internal thread section is provided on the lower inner wall of the receiving cavity, and an external thread section is provided on the outer wall of the limiting and sealing member to cooperate with the internal thread section. Tightening the limiting and sealing member applies force to the elastic support member and the zero-position standard member.

7. The zero-position calibration fixture for slide valve parts as described in claim 1, characterized in that, The positioning rod is provided with a rotating hole located in the mounting hole. The clamping block is provided with an assembly hole arranged coaxially with the rotating hole and a connecting shaft passing through the assembly hole and the rotating hole. The connecting shaft is rotatably connected to the positioning rod, and the axial direction of the connecting shaft is perpendicular to the length direction of the length detection component. The positioning rod is provided with a contact plane corresponding to the length detection component.

8. The zero-position calibration fixture for slide valve parts as described in claim 1, characterized in that, Also includes: The test support block has a through-mounted cavity for accommodating the valve core and sleeve assembly to be tested; The test support block has a mounting surface for mounting the clamping block, and a through hole communicating with the mounting cavity is provided on the mounting surface.

9. A method for zeroing a valve core, characterized in that, The zero-position calibration fixture for slide valve-type parts as described in claim 8 is used; comprising: S1: The zero-position standard component, the elastic support component, and the limiting and sealing component are installed on the reference calibration module; the positioning rod and the length detection component are installed on the clamping block; and the clamping block is assembled on the reference calibration module. S2: Manipulate the movement of the limiting and sealing component to compress the elastic support component. The elastic support component pushes the zero-position standard component upward, so that the centering cone surface and the outer cone surface of the positioning rod are fitted together and installed to ensure that the positioning rod automatically maintains a vertical state. Set the reading of the length detection component to zero and complete the standard zero-position calibration. S3: Install the valve core and valve sleeve assembly to be tested on the test support block. The adjusting parts at both ends of the valve core and valve sleeve assembly to be tested are installed at both ends of the test support block, and the slots on the valve core correspond to the through holes. S4: Disassemble the clamping block and fix it on the mounting surface of the test bearing block. The lower end of the positioning rod passes through the through hole and enters the slot of the valve core. S5: Observe the offset reading of the length detection component, and compensate for the offset by changing the thickness of the adjusting shims on the two adjusting components according to the offset direction of the reading, until the length detection component reading returns to zero, the valve core is at the geometric center of the valve sleeve, and the zero-position adjustment of the valve core and valve sleeve assembly to be adjusted is completed.

10. The valve core zeroing method as described in claim 9, characterized in that, Also includes: S6: Re-inspect the valve core, manipulate the adjusting component to move linearly in both directions with the same amplitude, and observe the offset reading of the length detection component; if the offset readings are inconsistent, readjust the thickness of the adjusting shim.

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