A star-shaped sealing ring inner diameter detection device

Abstract

This invention relates to a star-shaped sealing ring inner diameter detection device, comprising a base with a mounting surface at one end, and positioning elements spaced apart on the mounting surface; two expansion components symmetrically arranged on the base, each expansion component including an expansion plate and an elastic element, the two expansion plates having a semi-circular outer contour on their opposite sides, and a bearing portion extending circumferentially on the semi-circular outer contour; the expansion plates and positioning elements being arranged one-to-one; the elastic element being connected to the expansion plate and the corresponding positioning element; a driving unit for moving the two expansion plates away from each other; and a detection unit including a spring, a strain gauge, and a detection circuit. Grooves are formed on the semi-circular outer contour of the expansion plates, the two ends of the spring are elastically engaged with the two side walls of the groove, the strain gauge is connected to the spring, and the detection circuit is electrically connected to the strain gauge. The star-shaped sealing ring inner diameter detection device provided in this application can precisely measure the inner diameter of the star-shaped sealing ring.

Description

Technical Field

[0001] This invention relates to the field of measuring the inner diameter of irregularly shaped parts, and specifically to a device for detecting the inner diameter of a star-shaped sealing ring. Background Technology

[0002] Star-shaped seals are widely used in rotary or reciprocating dynamic seals in hydraulic and pneumatic structures. Compared to O-rings, the main characteristic of star-shaped seals is their lower torque and better sealing effect at the same compression. They play a crucial role in the dynamic seals of orientation and pitch components in optoelectronic products. Currently, the rotational torque requirements of orientation and pitch components in optoelectronic products are becoming increasingly smaller. To meet these torque requirements, the compression of star-shaped seals is generally required to be no more than 0.1 mm. This reduction in compression leads to stricter dimensional requirements for the star-shaped seals. Because star-shaped seals are generally made of nitrile rubber, a relatively soft and elastic material, the inner diameter accuracy after injection molding is very low, often with tolerances on the millimeter level.

[0003] In a known orientation assembly, the inner diameter of the star-shaped seal is 164.49 ± 1.02 mm, requiring a single-sided compression of 0.08 mm. The inner diameter tolerance is 2.04 mm, equivalent to 25.5 times the compression. After determining the structural dimensions of the sealing position, the seal size required to meet the compression requirement is quite stringent.

[0004] Because the star-shaped sealing ring is made of soft material, it cannot be measured using calipers or other standard measuring equipment. In existing technology, during assembly, the sealing rings are individually installed into the orientation assembly to test the torque, thus determining their suitability. This testing process requires a significant amount of trial assembly time, greatly reducing assembly efficiency. When a batch of sealing rings fails to meet requirements, the orientation assembly is machined again, adding extra processing and transport time, further limiting the assembly efficiency of the orientation components. Currently, there is no suitable mechanical measurement method. While visual inspection instruments exist on the market, the soft material of the star-shaped sealing ring makes it difficult to arrange it into a circle on a flat surface. The inspection instrument measures continuous segments of concave and convex arcs, resulting in significant roundness errors. Furthermore, the instrument uses light projection for inspection, and since the star-shaped ring has a certain height, the light is not perpendicular, introducing measurement errors. Therefore, the demand for a device that can accurately measure the inner diameter of the star-shaped sealing ring is increasing. Summary of the Invention

[0005] Based on the above description, the present invention provides a star-shaped sealing ring inner diameter detection device to solve the technical problems of difficulty and large error in the detection of star-shaped sealing ring inner diameter in the prior art.

[0006] The technical solution of the present invention to solve the above-mentioned technical problems is as follows:

[0007] A star-shaped sealing ring inner diameter detection device, comprising:

[0008] A base, one end of which has a mounting surface, and positioning elements are spaced apart on the mounting surface;

[0009] Two expansion components are symmetrically arranged on the base. Each expansion component includes an expansion plate and an elastic element. The two expansion plates are arranged opposite each other and have a semi-circular outer contour on one side. A bearing portion is formed on the semi-circular outer contour extending circumferentially. The expansion plate and the positioning element are arranged in a one-to-one correspondence. The elastic element is connected to the expansion plate and the corresponding positioning element so that the two expansion plates are close to each other.

[0010] A drive unit, the drive unit being used to move the two expansion plates away from each other;

[0011] The detection unit includes a spring, a strain gauge, and a detection circuit. A groove is formed on the semi-circular outer contour of the expansion plate. The two ends of the spring are elastically engaged with the two side walls of the groove. The strain gauge is connected to the spring. The detection circuit is electrically connected to the strain gauge and can convert the elastic deformation of the strain gauge into a change in electrical physical parameters.

[0012] Compared with the prior art, the technical solution of this application has the following beneficial technical effects:

[0013] The star-shaped seal inner diameter measuring device provided in this application can precisely measure the inner diameter of star-shaped seals, ensuring that during assembly, a star-shaped seal with an appropriate inner diameter can be selected based on the dimensions of the structural components and the amount of compression at the sealing location. This avoids the need for blindly testing seals and measuring torque, saving manual assembly time. Furthermore, different batches of products do not require repeated testing of previously tested seals; the size of the star-shaped seal can be directly determined according to product needs, improving assembly efficiency. This device can measure star-shaped seals with different inner diameters by changing the expansion plate or setting different strain stresses, offering a wide measurement range applicable to most products.

[0014] Based on the above technical solution, the present invention can be further improved as follows.

[0015] Furthermore, the drive unit includes a propulsion shaft and a pressure block. The pressure block is composed of two mutually symmetrical semi-rings. The middle parts of the two semi-rings can cooperate to form a conical hole. The side of the semi-rings away from the conical hole can push the expansion plate to move in a direction away from each other. The propulsion shaft has a conical head that cooperates with the conical hole.

[0016] Furthermore, the expansion plate has an abutment portion at the center of the side opposite to the semi-circular outer contour, and the driving unit also includes a transmission block, the two sides of which abut against the semi-ring and the abutment portion, respectively.

[0017] Furthermore, a cover plate is connected to the base, the cover plate is located on the side of the expansion assembly away from the mounting surface, a threaded hole is formed on the cover plate, and a fine thread is formed on the push shaft to mate with the threaded hole.

[0018] Furthermore, the end of the propulsion shaft away from the conical head has an external hexagonal structure.

[0019] Furthermore, a limiting hole is formed on the expansion plate, and the expansion plate is movably sleeved on the positioning member through the limiting hole. The elastic member is a compression spring and its two ends are connected to the side wall of the limiting hole and the positioning member.

[0020] Furthermore, the detection circuit includes a power supply, a full-bridge circuit module, and a voltmeter. The strain gauge is electrically connected to the full-bridge circuit module, and the full-bridge circuit module is electrically connected to both the power supply and the voltmeter.

[0021] Furthermore, the power source is a DC power source. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of a star-shaped sealing ring inner diameter detection device provided in an embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram of the assembly of the base, two expansion components, and the drive unit;

[0024] Figure 3 This is a disassembly diagram of the base and two expansion components;

[0025] Figure 4 for Figure 2 A cross-sectional schematic diagram;

[0026] Figure 5 This is a schematic diagram of the propulsion shaft. Detailed Implementation

[0027] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0029] It is understood that spatial relation terms such as "below," "under," "below," "below," "above," "above," etc., can be used here to describe the relationship between one element or feature shown in the figure and other elements or features. It should be understood that, in addition to the orientation shown in the figure, spatial relation terms also include different orientations of the device in use and operation. For example, if the device in the figure is flipped, the element or feature described as "below" or "below" of the other element or feature will be oriented "above" the other element or feature. Therefore, the exemplary terms "below" and "below" can include both upper and lower orientations. Furthermore, the device may also include other orientations (e.g., rotated 90° or other orientations), and the spatial descriptive terms used herein will be interpreted accordingly.

[0030] It should be noted that when one element is considered to be "connected" to another element, it can be directly connected to the other element or connected to the other element through an intermediary element. In the following embodiments, "connection" should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have the transmission of electrical signals or data between them.

[0031] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising,” “including,” or “having,” etc., specify the presence of the stated feature, whole, step, operation, component, part, or combination thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof.

[0032] As shown in the figure, this application

[0033] like Figure 1 As shown in the figure, this application provides a star-shaped sealing ring inner diameter detection device, which includes a base 10, two expansion components 20, a drive unit 30 and a detection unit.

[0034] The base 10 serves as a support, and its upper end has a mounting surface. Positioning elements 11 are spaced apart on the mounting surface. In this embodiment, the base 10 has a symmetrical structure on both sides, and the positioning elements 11 are positioned on both sides of the mounting surface relative to its symmetrical reference surface.

[0035] Combination Figures 2 to 4As shown, two expansion components 20 are symmetrically arranged on the mounting surface. Each expansion component 20 includes an expansion plate 21 and an elastic element 22. The expansion plate 21 has a semi-circular plate structure. The two expansion plates 21 are arranged opposite each other and have a semi-circular outer contour on the side that is away from each other. That is, the two expansion plates 21 are two halves of a circular structure that are divided equally. When they are completely close together, they can be combined into a circular plate shape.

[0036] The semi-circular outer contour has a circumferentially extending support portion 211 for placing a star-shaped sealing ring.

[0037] The expansion plate 21 and the positioning member 11 are respectively arranged in a one-to-one correspondence. The elastic member 22 is connected to the expansion plate 21 and the corresponding positioning member 11 so that the two expansion plates 21 are close to each other. Specifically, a limiting hole 21a is formed on the expansion plate 21. The expansion plate 21 is movably sleeved on the positioning member 11 through the limiting hole 21a. The elastic member 22 is a compression spring and its two ends are connected to the side wall of the limiting hole 21a and the positioning member 11.

[0038] The drive unit 30 is used to move the two expansion plates 21 away from each other.

[0039] Combination Figure 5 As shown, the drive unit 30 includes a propulsion shaft 31 and a pressure block 32. The pressure block 32 is composed of two mutually symmetrical semi-rings 321. The middle parts of the two semi-rings 321 can cooperate to form a conical hole. That is, the middle part of each semi-ring 321 is a groove with a sidewall that is half of the conical hole. When the two semi-rings 321 are connected, the two grooves can form a complete conical hole. The side of the semi-ring 321 away from the conical hole can push the expansion plate 21 to move away from each other. The propulsion shaft 31 has a conical head 311 that cooperates with the conical hole. When the conical head 311 is fitted into the conical hole formed by the two semi-rings 321, the propulsion shaft is continued to be pushed axially, and the two semi-rings 321 can move away from each other, thereby pushing the outer expansion plate 21 to move away from each other.

[0040] The expansion plate 21 has an abutment portion 212 in the middle of the side opposite to the semi-circular outer contour. The driving unit 30 also includes a transmission block 33. The two sides of the transmission block 33 abut against the semi-ring 321 and the abutment portion 212 respectively. The transmission block 33 applies the thrust applied by the semi-ring 321 to the abutment portion 212, thereby pushing the semi-circular outer contours of the two expansion plates to expand outward in a stable manner.

[0041] In this embodiment, a cover plate 12 is connected to the base 10. The cover plate 12 is located on the side of the expansion assembly 20 away from the mounting surface. A threaded hole 12a is formed on the cover plate 12. A fine thread 312 that mates with the threaded hole 12a is formed on the push shaft 31. By rotating the push shaft 31, the fine thread 312 can be rotated to engage with the threaded hole 12a, thereby causing the push shaft 31 to move axially.

[0042] To facilitate the turning of the push shaft 31 with a wrench, the end of the push shaft 31 away from the tapered head 311 is formed with an external hexagonal structure.

[0043] The detection unit includes a spring sheet 41, a strain gauge 42, and a detection circuit 43. A groove 21b is formed on the semi-circular outer contour of the expansion plate 21. The two ends of the spring sheet 41 are elastically engaged with the two side walls of the groove 21b. The strain gauge 42 is connected to the spring sheet 41. The detection circuit 43 is electrically connected to the strain gauge 42 and can convert the elastic deformation of the strain gauge 42 into a change in electrical physical parameters.

[0044] In this preferred embodiment, the detection circuit 43 includes a power supply 431, a full-bridge circuit module 432, and a voltmeter 433. The strain gauge 42 is electrically connected to the full-bridge circuit module 432, and the full-bridge circuit module 432 is electrically connected to the power supply 431 and the voltmeter 433 respectively. More preferably, the power supply is a DC power supply.

[0045] When strain gauge 42 deforms, the voltage across its terminals in the circuit will change accordingly. Even a very small deformation will cause a change in voltage. Therefore, the detection principle of this application is as follows: the star-shaped sealing ring is opened by the expansion plate 21. When the voltage value of voltmeter 433 in the detection circuit 43 changes, the spring 41 is squeezed by the inside of the star-shaped sealing ring and just begins to deform. At this time, the star-shaped sealing ring is just in the critical state of being fully opened and elastically stretched. Its inner circumference is its circumference in its natural state. The inner diameter of the star-shaped sealing ring can be calculated based on this circumference.

[0046] The mathematical model expression for the reaction is as follows: the radius of the semi-circular outer contour corresponding to the expansion plate 21 is defined as r, the inner diameter of the star-shaped sealing ring is defined as R, and the distance between the two expansion plates 21 is defined as D under the above critical state.

[0047] According to geometric principles, we have:

[0048] Given r, we only need to measure the size of D to calculate R.

[0049] The specific usage process of this application is as follows:

[0050] Place the base 10 horizontally on a water platform, ensuring the upper surface of the bearing portion 211 is horizontal. Place the star-shaped sealing ring on the bearing portion 211 of the two expansion plates 21 of the measuring device, ensuring the end face of the star-shaped sealing ring is flat to eliminate measurement errors caused by the inclination of the star-shaped sealing ring's cross-section. Adjust the output voltage of the DC power supply 431 to 5V, and turn the push shaft 31. The connecting thread between the push shaft 31 and the cover plate 12 generates axial displacement, causing the push shaft 31 to move downwards. The push shaft 31 drives the semi-ring 321 to generate radial displacement through the inclined surface of the tapered hole, causing the two expansion plates 21 to compress the spring 22, move outwards, and press against the star-shaped sealing ring. When the star-shaped sealing ring is compressed and subjected to a small force, the detection circuit 43, through the full-bridge circuit module 432, reflects the deformation as a change in the reading of the voltmeter 433. At this time, it indicates that the spring 41 and strain gauge 42 have been compressed and deformed, and the turning of the push shaft 31 is stopped. Measure the distance D between the two expansion plates 21, calculate the circumference of the inner circle of the star-shaped ring (2πr + 2D), and calculate the inner diameter.

[0051] As described above, the star-shaped sealing ring inner diameter detection device provided in this application can precisely measure the inner diameter of the star-shaped sealing ring. This ensures that during assembly, a star-shaped sealing ring with a suitable inner diameter can be selected based on the dimensions of the structural components and the amount of compression at the sealing location. This avoids the need for blindly testing sealing rings and measuring torque, saving manual assembly time. Furthermore, different batches of products do not require repeated testing of previously tested sealing rings; the size of the star-shaped sealing ring can be directly determined according to product needs, improving assembly efficiency. This device can measure star-shaped sealing rings with different inner diameters by changing the expansion plate or setting different strain stresses, offering a wide measurement range applicable to most products.

[0052] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A device for detecting the inner diameter of a star-shaped sealing ring, characterized in that, include: A base, one end of which has a mounting surface, and positioning elements are spaced apart on the mounting surface; Two expansion components are symmetrically arranged on the base. Each expansion component includes an expansion plate and an elastic element. The two expansion plates are arranged opposite each other and have a semi-circular outer contour on one side. A bearing portion is formed on the semi-circular outer contour extending circumferentially. The expansion plate and the positioning element are arranged in a one-to-one correspondence. The elastic element is connected to the expansion plate and the corresponding positioning element so that the two expansion plates are close to each other. A drive unit, the drive unit being used to move the two expansion plates away from each other; The detection unit includes a spring, a strain gauge, and a detection circuit. A groove is formed on the semi-circular outer contour of the expansion plate. The two ends of the spring are elastically engaged with the two side walls of the groove. The strain gauge is connected to the spring. The detection circuit is electrically connected to the strain gauge and can convert the elastic deformation of the strain gauge into a change in electrical physical parameters. The expansion plate has a limiting hole, and the expansion plate is movably sleeved on the positioning member through the limiting hole. The elastic member is a compression spring and its two ends are connected to the side wall of the limiting hole and the positioning member.

2. The star-shaped sealing ring inner diameter detection device according to claim 1, characterized in that, The drive unit includes a propulsion shaft and a pressure block. The pressure block consists of two mutually symmetrical semi-rings. The middle parts of the two semi-rings can cooperate to form a conical hole. The side of the semi-rings away from the conical hole can push the expansion plate to move away from each other. The propulsion shaft has a conical head that cooperates with the conical hole.

3. The star-shaped sealing ring inner diameter detection device according to claim 2, characterized in that, The expansion plate has an abutment portion in the middle of the side opposite to the semi-circular outer contour, and the driving unit also includes a transmission block, the two sides of which abut against the semi-ring and the abutment portion, respectively.

4. The star-shaped sealing ring inner diameter detection device according to claim 2, characterized in that, A cover plate is connected to the base, the cover plate is located on the side of the expansion assembly away from the mounting surface, a threaded hole is formed on the cover plate, and a fine thread is formed on the push shaft that mates with the threaded hole.

5. The star-shaped sealing ring inner diameter detection device according to claim 4, characterized in that, The end of the propulsion shaft away from the conical head has an external hexagonal structure.

6. The star-shaped sealing ring inner diameter detection device according to claim 1, characterized in that, The detection circuit includes a power supply, a full-bridge circuit module, and a voltmeter. The strain gauge is electrically connected to the full-bridge circuit module, and the full-bridge circuit module is electrically connected to both the power supply and the voltmeter.

7. The star-shaped sealing ring inner diameter detection device according to claim 6, characterized in that, The power source is a DC power source.

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