Measuring tool for measuring the center distance of a slider arc raceway and a measuring method thereof

Abstract

The present application relates to a measuring tool for measuring the center distance of a slider arc raceway and a measuring method thereof, a main frame, the main frame comprising a measuring arm and a fixed spherical fulcrum unit, a movable spherical fulcrum; a measuring mechanism and a pre-tightening mechanism are arranged on the measuring arm, the fixed spherical fulcrum unit comprises a first fixed spherical fulcrum and a second fixed spherical fulcrum, and the two fixed spherical fulcrums are respectively provided with two fixed balls; the measuring mechanism comprises a measuring needle and a dial gauge; the pre-tightening mechanism comprises two independent pre-tightening springs; the measuring method comprises steps of standard sample calibration, tool installation and positioning, workpiece measurement and data determination; the tool is designed by using the three-point centering geometric constraint and double-spring elastic pre-tightening composite principle, the automatic positioning of the center point of the raceway generatrix is realized through structure optimization, manual calculation or adjustment is not needed, the center distance deviation is directly read, and the measuring accuracy and efficiency of the center distance of the large slider arc raceway are greatly improved, and the problem of inaccurate positioning of the conventional tool is solved from the root.

Description

Technical Field

[0001] This invention relates to a measuring tool and method for measuring the center distance of the arc raceway of a slider, used for detecting the center distance between the inner and outer raceways of a slider, and belongs to the field of equipment testing technology. Background Technology

[0002] The slider is a crucial component of extra-large arc-shaped guide rail pairs. Its raceway matches the steel ball and the guide rail raceway to form clearance. This clearance range is very small, making the dimensional accuracy of the slider raceway extremely important. For accurate measurements, the center point of the raceway must be found in each measurement. Traditional fine-tipped dial indicators can only roughly locate the center of the arc, not provide precise measurements.

[0003] In the manufacturing and inspection of large slider arc raceways, the characteristics of the slider raceway are: it consists of four large arcs with a radius of R4500~R8000, and the generatrix of the raceway is a small semi-circular arc with a radius of R13.2mm~R19.8mm. After the raceway is ground, the center distance between the inner and outer raceways needs to be accurately measured. However, conventional measuring tools are limited by their structure and cannot accurately locate the center point of the arc generatrix, resulting in low reliability and large errors in the measured values. This makes it difficult to meet the quality control requirements of high-precision assembly and seriously affects the product qualification rate and production efficiency. Summary of the Invention

[0004] To address the problem that traditional measuring tools cannot accurately locate the center point of the arc generatrix, resulting in low reliability of measurement data, this invention aims to design a measuring tool and its measurement method for measuring the center distance of the arc raceway of a slider, thereby achieving high-precision, high-efficiency, and high-reliability measurement of the center distance of the arc raceway of a large slider.

[0005] To achieve the above objectives, the technical solution adopted by this invention is as follows: a measuring tool for measuring the center distance of a slider arc raceway, comprising: a main frame, the main frame including a measuring arm and fixed spherical fulcrum units and movable spherical fulcrums distributed at both ends of the measuring arm; a measuring mechanism and a pre-tightening mechanism are provided on the measuring arm, the fixed spherical fulcrum unit including a first fixed spherical fulcrum, a second fixed spherical fulcrum and a support block perpendicular to the measuring arm, the two fixed spherical fulcrums each having two fixed balls, the two fixed balls being placed in the support block; the measuring mechanism includes a measuring needle and a dial indicator; the dial indicator is installed in the middle of the measuring arm, and a measuring needle is provided at one end of the measuring arm located in the direction of the fixed spherical fulcrum unit, the dial indicator being linked to the measuring needle through a linkage, the tip of the measuring needle extending to the outer end of the measuring arm; the pre-tightening mechanism includes two independent pre-tightening springs, the two pre-tightening springs being respectively sleeved on the outside of the measuring arm and disposed inside the measuring arm; the movable spherical fulcrum is installed at the end of the measuring arm and is slidably disposed with the measuring arm; Based on the above scheme, the measuring needle at one end of the measuring arm in the direction of the fixed spherical fulcrum unit forms the measuring point of the gauge, and the measuring point is located in the symmetrical mid-plane of the two fixed spherical fulcrums. Furthermore, the movable spherical fulcrum includes a mounting base and a movable ball, with a V-shaped groove provided in the mounting base; Based on the structure of the measuring tool described above, the measuring tool is fitted between the inner raceway and the outer raceway of the workpiece. The movable ball of the movable spherical fulcrum at one end of the measuring arm is placed in the V-shaped groove of the mounting base and fits against the inner raceway of the workpiece. The two fixed spherical fulcrums at the other end of the measuring arm are fitted with the measuring point and pressed against the outer raceway of the workpiece. Furthermore, the radii of the first fixed spherical fulcrum and the second fixed spherical fulcrum are matched with the raceway generatrix; Furthermore, the raceway generatrix is ​​a small semi-circular arc with a diameter of R13.2mm to R19.8mm.

[0006] The radius of the movable spherical fulcrum described above is the same as that of the fixed spherical fulcrum; Furthermore, the movable spherical fulcrum and the two fixed spherical fulcrums form a three-point positioning system.

[0007] Furthermore, a V-shaped groove is provided in the support block perpendicular to the measuring arm to accommodate two fixed balls, and the two fixed balls are respectively placed in the V-shaped groove of the support block; Furthermore, the measuring point is collinear with the center of the movable spherical fulcrum.

[0008] Furthermore, the elastic coefficients of the two pre-tensioning springs in the pre-tensioning mechanism are matched, and the compression amount can be finely adjusted; the pre-tensioning spring sleeved on the outside of the measuring arm is the outer spring, and the pre-tensioning spring set inside the measuring arm is the inner spring.

[0009] The design principle of the measuring tool structure based on this application is a combination of the three-point centering principle and the double-spring elastic preload principle. The three-point centering principle is to form a three-point support structure by using two fixed spherical fulcrums and one movable spherical fulcrum. All three points are in contact with the raceway generatrix. The measuring point is designed in the symmetrical middle plane of the two fixed spherical fulcrums and is collinear with the center of the movable spherical fulcrum. Due to geometric constraints, it automatically falls on the arc center point of the raceway generatrix, thus ensuring positioning accuracy from a structural perspective. The dual-spring elastic preload principle involves two independent preload springs in the preload mechanism of the main frame. These springs drive the extension and retraction of the movable spherical fulcrum and the measuring point, ensuring a tight fit between the three spherical fulcrums and the raceway generatrix, and precise contact between the measuring point and the center point. This completely eliminates measurement gaps and avoids errors caused by incomplete contact. Based on this principle, through direct linkage between the measuring point and the dial indicator in the measuring mechanism, after calibration with the standard sample, the center distance difference between the measured workpiece and the standard sample can be directly displayed by the dial indicator pointer deflection, eliminating the need for complex data conversion and simplifying the measurement process. Finally, the dial indicator data is used for judgment. The judgment standard is to compare the deviation value displayed by the dial indicator with the tolerance range specified in the design drawings. If the reading is within the tolerance range, the raceway is judged to be qualified; otherwise, it is judged to be unqualified.

[0010] The method for measuring the center distance of the slider arc raceway based on the above-mentioned gauge structure and principle includes the following steps: (1) Standard sample calibration The raceway center distance of the standard sample was determined using a coordinate measuring machine to establish the measurement benchmark. Place the measuring instrument stably on the corresponding raceway of the standard sample, and gently press the measuring instrument so that the two fixed spherical fulcrums and the movable spherical fulcrum are in close contact with the raceway generatrix, and achieve stable positioning by relying on the spring preload. Observe the state of the dial indicator pointer. After the pointer is completely stable, rotate the dial indicator so that the pointer points precisely to the "0" mark to complete the reference calibration. (2) Installation and positioning of measuring tools After calibration, the measuring point (measuring needle) of the measuring instrument is attached to the arc surface of the outer raceway of the workpiece with two fixed spherical fulcrums to ensure stable contact. Slowly push one end of the movable spherical fulcrum of the measuring tool so that the movable spherical fulcrum fits against the arc surface of the inner raceway of the workpiece, and achieve stable positioning through the spring preload; (3) Workpiece measurement After the above-calibrated measuring instrument is placed stably on the raceway of the workpiece being measured, ensure that the three spherical support points are in close contact with the raceway generatrix. Keep the measuring tool stable. After the dial indicator pointer stabilizes, directly read the dial reading. This value is the deviation between the workpiece raceway center distance and the standard sample. (4) Data Judgment If the percentage reading is within the tolerance range specified in the design drawings, the raceway is deemed qualified; if the percentage reading exceeds the tolerance range specified in the design drawings, the raceway is deemed unqualified.

[0011] The beneficial effects of this invention are: This measuring tool adopts a three-point centering geometric constraint and a double-spring elastic preload composite design. Through structural optimization, it achieves automatic positioning of the center point of the raceway generatrix, eliminating the need for manual calculation or adjustment. It directly reads the center distance deviation, significantly improving the measurement accuracy and efficiency of the center distance of the large slider arc raceway, and fundamentally solving the problem of inaccurate positioning of conventional measuring tools. Attached Figure Description

[0012] Figure 1 This is a structural diagram of the measuring tool of the present invention.

[0013] Figure 2 for Figure 1 Enlarged view of point A.

[0014] Figure 3 This is a side view of the measuring tool of the present invention.

[0015] Figure 4 This is a diagram showing the measuring instrument of the present invention located at the measuring position at the front end of the raceway.

[0016] Figure 5 This is a diagram showing the measuring instrument of the present invention located at the measuring position at the middle of the raceway.

[0017] Figure 6 This is a diagram showing the measuring instrument of the present invention located at the measuring position at the rear end of the raceway.

[0018] In the figure, 1. Measuring arm, 2. Movable spherical fulcrum, 3. First fixed spherical fulcrum, 4. Second fixed spherical fulcrum, 5. Support block, 6. Dial indicator, 7. Measuring point, 8. Mounting base, 9. Inner raceway of slider, 10. Outer raceway of slider, 11. Outer spring, 12. Inner spring. Detailed Implementation

[0019] To make the structure and function of the present invention clearer, the technical solutions in the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0020] like Figure 1-6The measuring instrument for measuring the center distance of the arc raceway of the slider, as shown, includes: a main frame, which includes a measuring arm 1 and fixed spherical fulcrum units and movable spherical fulcrums 2 distributed at both ends of the measuring arm 1; the measuring arm 1 is provided with a measuring mechanism and a pre-tightening mechanism; the fixed spherical fulcrum unit includes a first fixed spherical fulcrum 3, a second fixed spherical fulcrum 4, and a support block 5 perpendicular to the measuring arm 1, with two fixed spherical fulcrums each having two fixed balls, which are placed in the support block 5; the measuring mechanism includes a measuring needle and a dial indicator 6; the dial indicator 6 is installed in the middle of the measuring arm 1, and a measuring needle is provided at one end of the measuring arm 1 in the direction of the fixed spherical fulcrum unit, the dial indicator 6 is linked to the measuring needle through a linkage, and the tip of the measuring needle extends to the outer end of the measuring arm 1; the pre-tightening mechanism includes two independent pre-tightening springs, one sleeved on the outside of the measuring arm 1 and the other disposed inside the measuring arm 1; the movable spherical fulcrum 2 is installed at the end of the measuring arm 1 and is slidably disposed with the measuring arm 1; Based on the above scheme, the measuring needle at one end of the measuring arm 1 in the direction of the fixed spherical fulcrum unit forms the measuring point 7 of the measuring instrument, and the measuring point 7 is located in the symmetrical mid-plane of the two fixed spherical fulcrums. Furthermore, the movable spherical fulcrum 2 includes a mounting base 8 and a movable ball, with a V-shaped groove provided in the mounting base 8; Based on the structure of the measuring tool described above, the measuring tool is fitted between the inner raceway 9 (inner raceway of the workpiece) and the outer raceway 10 (outer raceway of the workpiece) of the slider. The movable ball of the movable spherical fulcrum 2 at one end of the measuring arm 1 is placed in the V-shaped groove of the mounting base 8 and fits against the inner raceway 9 of the slider. The two fixed spherical fulcrums at the other end of the measuring arm 1 are fitted with the measuring point 7 and pressed against the outer raceway 10 of the slider. Furthermore, the radii of the first fixed spherical fulcrum 3 and the second fixed spherical fulcrum 4 are matched with the raceway generatrix. The fixed sphere is made of high carbon chromium bearing steel. The purpose of setting the two fixed spherical fulcrums is to provide stable two-point support, accurately fit the arc surface of the raceway generatrix, and serve as the overall positioning reference. Furthermore, the raceway generatrix is ​​a small semi-circular arc with a diameter of R13.2mm to R19.8mm.

[0021] The radius of the movable spherical fulcrum 2 is the same as that of the fixed spherical fulcrum. The movable spherical fulcrum 2 is driven by the pre-tension spring inside the measuring arm 1 in the pre-tensioning mechanism and can extend and retract along the guide rail. Furthermore, the movable spherical fulcrum 2 and the two fixed spherical fulcrums form a three-point positioning system, realizing automatic centering of the raceway busbar.

[0022] Furthermore, a V-shaped groove for accommodating two fixed balls is provided in the support block 5 perpendicular to the measuring arm 1, and the two fixed balls are respectively placed in the V-shaped groove of the support block 5; Furthermore, the center of measuring point 7 is collinear with the center of the movable spherical fulcrum 2. Its function is to automatically locate the center point of the arc of the raceway generatrix and convert the change in center distance into a displacement signal, which is then transmitted to the dial indicator 6 in the measuring mechanism.

[0023] In this scheme, the dial indicator 6 is linked to the measuring needle to realize the linkage between the dial indicator 6 and the measuring point 7. The purpose is to magnify and display the small displacement of the measuring point 7 and directly read the center distance deviation value.

[0024] Furthermore, the elastic coefficients of the two pre-tensioning springs in the pre-tensioning mechanism are matched, and the compression amount can be finely adjusted; the pre-tensioning spring sleeved on the outside of the measuring arm 1 is the outer spring 11, which is used to push the measuring point 7 and the fixed spherical fulcrum, and the pre-tensioning spring set inside the measuring arm 1 is the inner spring 12, which is used to push the movable spherical fulcrum 2 so that it fits tightly against the inner raceway 9 of the slider; the setting of the two pre-tensioning springs ensures that all contact parts fit tightly, eliminates gaps, and ensures measurement stability.

[0025] The method for measuring the center distance of the slider arc raceway based on the above-mentioned gauge structure and principle includes the following steps: (1) Standard sample calibration The raceway center distance of the standard sample was determined using a coordinate measuring machine to establish the measurement benchmark. Place the measuring instrument stably on the corresponding raceway of the standard sample, and gently press the measuring instrument so that the two fixed spherical fulcrums and the movable spherical fulcrum are in close contact with the raceway generatrix, and achieve stable positioning by relying on the spring preload. Observe the state of the dial indicator pointer. After the pointer is completely stable, rotate the dial indicator so that the pointer points precisely to the "0" mark to complete the reference calibration. (2) Installation and positioning of measuring tools After calibration, the measuring point 7 (measuring needle) of the measuring instrument is attached to the arc surface of the outer raceway 10 of the slider with the two fixed spherical fulcrums to ensure stable contact; Slowly push one end of the movable spherical fulcrum 2 of the measuring tool so that the movable spherical fulcrum 2 fits against the arc surface of the inner raceway 9 of the slider, and achieve stable positioning through the spring preload; (3) Workpiece measurement After the above-calibrated measuring instrument is placed stably on the raceway of the workpiece being measured, ensure that the three spherical support points are in close contact with the raceway generatrix. Keep the measuring tool stable. After the pointer of dial indicator 6 stabilizes, directly read the dial reading. This value is the deviation between the center distance of the workpiece raceway and the standard sample. In this embodiment, to improve accuracy, measurements are repeatedly taken at three key locations: the front end, middle end, and rear end of the raceway, and the measurement values ​​are recorded each time. The average value of multiple measurements for the same raceway is calculated as the final center distance deviation value for that raceway. The specific measurement data details are as follows: Taking a raceway radius of R19.8 as an example (unit: mm), the raceway center distance is 237.878 + 0.10 (unit: mm).

[0026] (4) Data Judgment If the reading of dial indicator 6 is within the tolerance range specified in the design drawings, the raceway is deemed to be qualified; if the reading of dial indicator 6 exceeds the tolerance range specified in the design drawings, the raceway is deemed to be unqualified.

[0027] In this implementation, the final deviation value (the average value of the raceway obtained from parts 1, 2, and 3) is compared with the tolerance range specified in the design drawings. If the measurement result is within the tolerance range (0 to +0.1), the raceway is deemed qualified.

[0028] In this solution, the fixed spherical fulcrum, movable spherical fulcrum, preload spring, and dial indicator are all standardized components that can be quickly disassembled and replaced after wear. The maintenance process is simple and the long-term use cost is low. This measuring tool is easy to operate and has a low barrier to entry, thereby reducing labor costs and making it suitable for mass production.

[0029] The advantages of the measuring tools in this solution compared to conventional measuring tools are as follows: Raceway busbar center point positioning method: This gauge automatically positions itself using three-point centering without manual intervention; conventional gauges require manual estimation or indirect calculation, resulting in ambiguous positioning. Therefore, this gauge provides precise positioning and eliminates human error.

[0030] Measurement data reliability: The measurement data of this measuring tool has high reliability, while the measurement data of conventional measuring tools has low reliability, large deviation in repeated measurements, and no unified benchmark. Therefore, the data of this measuring tool is traceable and meets the requirements of quality control.

[0031] Compatible raceway specifications (generatrix radius): The ball support radius of this gauge is R13.2mm~R19.8mm, and it is compatible with 4 inner and outer raceways, which can cover the measurement needs of arc raceways with R13.2mm~R19.8mm. Conventional gauges require the replacement of gauges of different specifications and have poor compatibility. Therefore, this gauge has strong versatility and does not require frequent gauge replacement.

[0032] Maintenance cost: This measuring tool adopts a modular design, and the core components (ball pivot, spring, dial indicator) are all standardized parts. The parts can be quickly replaced after wear, resulting in low maintenance cost; while conventional measuring tools have high maintenance cost and the parts wear out quickly.

[0033] It should be noted that the parts of this invention not described in detail are prior art.

[0034] The above examples are merely preferred embodiments of the present invention. Obviously, the present invention is not limited to the above embodiments, and many variations are possible. All variations that can be directly derived or conceived by those skilled in the art from the disclosure of the present invention should be considered within the scope of protection of the present invention.

Claims

1. A measuring tool for measuring the center distance of the arc raceway of a slider, characterized in that, include: The main frame includes a measuring arm and fixed spherical fulcrum units and movable spherical fulcrums distributed at both ends of the measuring arm. The measuring arm is equipped with a measuring mechanism and a pre-tensioning mechanism. The fixed spherical fulcrum unit includes a first fixed spherical fulcrum, a second fixed spherical fulcrum, and a support block perpendicular to the measuring arm. Each of the two fixed spherical fulcrums has two fixed balls, which are housed within the support block. The measuring mechanism includes a measuring needle and a dial indicator. The dial indicator is installed in the middle of the measuring arm, and a measuring needle is located at one end of the measuring arm in the direction of the fixed spherical fulcrum unit. The dial indicator is linked to the measuring needle via a linkage, and the tip of the measuring needle extends to the outer end of the measuring arm. The pre-tensioning mechanism includes two independent pre-tensioning springs, one sleeved on the outside of the measuring arm and the other located inside the measuring arm. The movable spherical fulcrum is installed at the end of the measuring arm and slides along with it.

2. The measuring tool for measuring the center distance of the arc raceway of a slider according to claim 1, characterized in that: The measuring needle at one end of the measuring arm in the direction of the fixed spherical fulcrum unit forms the measuring point of the gauge, and the measuring point is located in the symmetrical mid-plane of the two fixed spherical fulcrums.

3. The measuring tool for measuring the center distance of the arc raceway of a slider according to claim 1, characterized in that: The movable spherical fulcrum includes a mounting base and a movable ball, with a V-shaped groove provided in the mounting base.

4. The measuring tool for measuring the center distance of the arc raceway of a slider according to claim 3, characterized in that: The measuring tool is fitted between the inner raceway and the outer raceway of the workpiece. The movable ball of the movable spherical fulcrum at one end of the measuring arm is placed in the V-shaped groove of the mounting base and fits against the inner raceway of the workpiece. The two fixed spherical fulcrums at the other end of the measuring arm are fitted with the measuring point and pressed against the outer raceway of the workpiece.

5. The measuring tool for measuring the center distance of the arc raceway of a slider according to claim 1, characterized in that: The radii of the first fixed spherical fulcrum and the second fixed spherical fulcrum are matched with the raceway generatrix; the raceway generatrix is ​​a small semicircle arc with a radius of R13.2 to R19.

8.

6. The measuring tool for measuring the center distance of the arc raceway of a slider according to claim 5, characterized in that: The radius of the movable spherical fulcrum is the same as that of the fixed spherical fulcrum.

7. The measuring tool for measuring the center distance of the arc raceway of a slider according to claim 1, characterized in that: The movable spherical fulcrum and the two fixed spherical fulcrums form a three-point positioning system.

8. The measuring tool for measuring the center distance of the arc raceway of a slider according to claim 2, characterized in that: The measuring point is collinear with the center of the movable spherical fulcrum.

9. The measuring tool for measuring the center distance of the arc raceway of a slider according to claim 1, characterized in that: The elastic coefficients of the two preload springs in the preload mechanism are matched; the preload spring sleeved outside the measuring arm is the outer spring, and the preload spring set inside the measuring arm is the inner spring.

10. A method for measuring the center distance of the slider arc raceway using the measuring instrument described in any one of claims 1-9, characterized in that, Includes the following steps: (1) Standard sample calibration; The raceway center distance of the standard sample was determined using a coordinate measuring machine to establish the measurement benchmark. Place the measuring instrument stably on the corresponding raceway of the standard sample, and gently press the measuring instrument so that the two fixed spherical fulcrums and the movable spherical fulcrum are in close contact with the raceway generatrix, and achieve stable positioning by relying on the spring preload. Observe the state of the dial indicator pointer. After the pointer is completely stable, rotate the dial indicator so that the pointer points precisely to the "0" mark to complete the reference calibration. (2) Installation and positioning of measuring tools; After calibration, the measuring needle of the measuring instrument is placed against the arc surface of the outer raceway of the workpiece with two fixed spherical fulcrums to ensure stable contact. Slowly push one end of the movable spherical fulcrum of the measuring tool so that the movable spherical fulcrum fits against the arc surface of the inner raceway of the workpiece, and achieve stable positioning through the spring preload; (3) Workpiece measurement; After the above-calibrated measuring instrument is placed stably on the raceway of the workpiece being measured, ensure that the three spherical support points are in close contact with the raceway generatrix. Keep the measuring tool stable. After the dial indicator pointer stabilizes, directly read the dial reading. This value is the deviation between the workpiece raceway center distance and the standard sample. (4) Data judgment; If the percentage reading is within the tolerance range specified in the design drawings, the raceway is deemed qualified; if the percentage reading exceeds the tolerance range specified in the design drawings, the raceway is deemed unqualified.

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