Tool and method for measuring spacing of parallel spiral grooves
By using a measuring fixture consisting of an outside micrometer, steel balls, and bushings, the problems of low efficiency and low accuracy in parallel spiral groove spacing measurement were solved, achieving high-precision spacing measurement suitable for irregularly shaped end face workpieces.
Patent Information
- Application Number
- CN202511813116.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-04
- Publication Date
- 2026-03-03
AI Technical Summary
In the existing technology, the method for measuring the spacing of parallel spiral grooves is inefficient and not very accurate, especially for workpieces with irregular end faces, making it difficult to achieve convenient and accurate measurement.
The measuring fixture includes an outside micrometer, steel balls, and a bushing. The steel balls are inserted into the spiral groove and secured in the inner flange. The bushing clamps the steel balls with the fixed or movable end of the micrometer, ensuring close contact with the bottom of the spiral groove. The spacing is calculated by combining the reading of the outside micrometer.
It enables convenient measurement of the spacing between parallel spiral grooves, improves measurement accuracy, avoids the influence of steel ball falling off or moving, and ensures the accuracy and reliability of the measurement.
Smart Images
Figure CN121594730A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of workpiece inspection technology, specifically relating to a measuring fixture and method for the spacing of parallel spiral grooves. Background Technology
[0002] Spiral grooves are grooves formed by cutting along a helical direction on the surface of a cylindrical workpiece. They are commonly found in shaft parts and are used for mechanical transmission or sealing. The machining of spiral grooves typically requires a milling machine, and the movement of the milling cutter and the workpiece must conform to the helical pattern.
[0003] In related technologies, after the outer surface of a workpiece is machined with multiple spiral grooves, it needs to undergo factory inspection, which mainly includes the groove depth and the distance between two parallel spiral grooves. In particular, the distance between two parallel spiral grooves is directly related to the subsequent mechanical installation and transmission efficiency of the workpiece.
[0004] However, the existing method for measuring the distance between two parallel spiral grooves mainly involves measuring the distance on the end face of the workpiece using a ruler. However, it is often difficult to align the ruler precisely with the bottom of the two parallel spiral grooves. Furthermore, some workpieces have irregularly shaped end faces, making it impossible to use a ruler directly. This results in low measurement efficiency and the inability to guarantee measurement accuracy. Summary of the Invention
[0005] In view of the above-mentioned defects or improvement needs of the prior art, the present invention provides a measuring fixture and method for measuring the spacing of parallel spiral grooves, the purpose of which is to conveniently measure the spacing between two parallel spiral grooves on the workpiece under test with high measurement accuracy.
[0006] To achieve the above objectives, in a first aspect, the present invention provides a measuring fixture for the spacing of parallel spiral grooves, the measuring fixture comprising an outside micrometer, two steel balls and two bushings; The diameter of each steel ball is smaller than the inner diameter of the corresponding bushing, and each steel ball is used to be inserted into the corresponding spiral groove of the workpiece to be tested. Each bushing has an inner flange on one end of its inner peripheral wall. The inner diameter of the inner flange is smaller than the diameter of the steel ball. The inner flange is used to hold the corresponding steel ball. The other end of each bushing is detachably fitted onto the fixed end or the movable end of the outer micrometer, so that the end face of the fixed end or the movable end abuts against the corresponding steel ball.
[0007] Optionally, one end of each bushing has an annular notch on its outer periphery, the annular notch being used to avoid obstructing the workpiece to be tested.
[0008] Optionally, in the axial direction of the bushing, the thickness of the annular notch is equal to the thickness of the inner flange.
[0009] Optionally, the inner peripheral wall of the inner flange is tapered, and the diameter of the inner flange decreases sequentially from the other end of the bushing to one end of the bushing.
[0010] Optionally, one of the bushings is on the movable end, and the other bushing is sleeved on the fixed end, and in the axial direction of the bushings, the length of one bushing is greater than the length of the other bushing.
[0011] Optionally, the inner peripheral wall of the other end of each bushing has a rounded corner.
[0012] Optionally, the outer peripheral wall of each bushing has anti-slip threads.
[0013] Secondly, the present invention provides a method for measuring the spacing of parallel helical grooves, the method being based on a measuring fixture for measuring the spacing of parallel helical grooves as described in the first aspect, the method comprising: S1. Insert each of the steel balls into the bushing from the other end of the corresponding bushing and lock them into the corresponding inner flange; S2. Place the two bushings onto the fixed end or the movable end of the outside micrometer, until each steel ball abuts against the end face of the fixed end or the movable end. S3. Place the workpiece to be tested on the workbench and screw the movable end so that the two steel balls are respectively inserted into the two parallel spiral grooves on the workpiece to be tested, until each steel ball is stuck at the bottom of the corresponding spiral groove. S4. Take a reading from the outside micrometer to obtain dimensional data, and calculate the distance between the two parallel spiral grooves using the dimensional data and the diameter of the steel ball.
[0014] Optionally, prior to step S2, the measurement method further includes: The outer peripheral wall of the fixed end, the outer peripheral wall of the movable end, and the inner peripheral walls of the two bushings are all coated with grease.
[0015] Optionally, after step S4, the measurement method further includes: Repeat steps S1-S4 to obtain the distance between two parallel spiral grooves at different positions along the axial direction of the workpiece under test, and calculate the average value.
[0016] The aforementioned improved technical features can be combined with each other as long as they do not conflict with each other.
[0017] In summary, the beneficial effects of the above-described technical solutions conceived by this invention compared with the prior art include: For the measuring fixture for the spacing of parallel spiral grooves provided in this embodiment of the invention, when measuring the spacing between two parallel spiral grooves of the workpiece to be measured, firstly, each steel ball is placed into the corresponding bushing from the other end and secured in the corresponding inner flange. The inner flange limits the steel ball, ensuring that the steel ball is clamped and fixed when it comes into contact with the fixed or movable end, thereby preventing the steel ball from falling off or moving. Then, the two bushings are respectively fitted onto the fixed or movable end of the outside micrometer until each steel ball abuts against the end face of the fixed or movable end, thus preventing gaps from forming between the steel ball and the fixed or movable end and affecting subsequent measurements.
[0018] Next, place the workpiece to be measured on the worktable and screw on the movable end to insert the two steel balls into the two parallel spiral grooves on the workpiece, until each steel ball is quickly locked at the bottom of the corresponding spiral groove. At this point, one side of the steel ball is in close contact with the bottom of the spiral groove, and the other side of the steel ball is in contact with the end face of the fixed end or the movable end. Thus, the workpiece and the two steel balls are precisely clamped between the movable and fixed ends. Finally, take a reading with an outside micrometer to obtain accurate dimensional data. Calculate the distance between the two parallel spiral grooves using the dimensional data and the diameter of the steel balls. The distance between the bottoms of the two parallel spiral grooves is the difference between the dimensional data and the diameter of the two steel balls, resulting in a high measurement accuracy.
[0019] In other words, the present invention provides a measuring fixture for the spacing of parallel spiral grooves, which can conveniently measure the spacing between two parallel spiral grooves on the workpiece under test with high measurement accuracy. Attached Figure Description
[0020] Figure 1 This is a schematic diagram of the structure of a measuring fixture for the spacing of parallel spiral grooves provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the use of a measuring fixture for the spacing of parallel spiral grooves provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the bushing structure according to an embodiment of the present invention; Figure 4 This is a cross-sectional schematic diagram of the bushing according to an embodiment of the present invention; Figure 5 This is a partial cross-sectional view of the measuring fixture in use according to an embodiment of the present invention; Figure 6 This is a flowchart of a method for measuring the spacing of parallel spiral grooves provided in an embodiment of the present invention.
[0021] In all the accompanying drawings, the same reference numerals denote the same technical features, specifically: 1. Outside micrometer; 11. Fixed end; 12. Moving end; 13. Handle; 2. Steel ball; 3. Bushing; 31. Inner flange; 32. Annular notch; 100. Workpiece to be measured; 101. Spiral groove. Detailed Implementation
[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.
[0023] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention 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 invention.
[0024] 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 at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0025] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.
[0026] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.
[0027] Example: Figure 1 This is a schematic diagram of a measuring fixture for the spacing of parallel spiral grooves provided in an embodiment of the present invention. Figure 2 This is a schematic diagram of the use of a measuring fixture for the spacing of parallel spiral grooves provided in an embodiment of the present invention, combined with... Figure 1 and Figure 2 As shown, the measuring fixture includes an outside micrometer 1, two steel balls 2, and two bushings 3.
[0028] The diameter of each steel ball 2 is smaller than the inner diameter of the corresponding bushing 3, and each steel ball 2 is used to be inserted into the corresponding spiral groove 101 of the workpiece to be tested 100 (that is, the radius of the steel ball 2 is smaller than the radius of the spiral groove 101).
[0029] Figure 3 This is a schematic diagram of the bushing structure according to an embodiment of the present invention. Figure 4 This is a cross-sectional schematic diagram of the bushing according to an embodiment of the present invention. Figure 5 This is a partial sectional view of the measuring fixture in use according to an embodiment of the present invention, combined with... Figures 3-5 As shown, one end of each bushing 3 has an inner flange 31 on its inner peripheral wall. The inner diameter of the inner flange 31 is smaller than the diameter of the steel ball 2. The inner flange 31 is used to hold the corresponding steel ball 2. The other end of each bushing 3 is detachably fitted onto the fixed end 11 or the movable end 12 of the outer diameter micrometer 1, so that the end face of the fixed end 11 or the movable end 12 abuts against the corresponding steel ball 2.
[0030] For the measuring fixture for the spacing of parallel spiral grooves provided in this embodiment of the invention, when measuring the spacing between the two parallel spiral grooves 101 of the workpiece 100 to be measured, firstly, each steel ball 2 is placed into the corresponding bushing 3 from the other end of the bushing 3 and secured in the corresponding inner flange 31. The inner flange 31 serves to limit the steel ball 2, ensuring that the steel ball 2 is clamped and fixed when it comes into contact with the fixed end 11 or the movable end 12, thereby preventing the steel ball 2 from falling off or moving. Then, the two bushings 3 are respectively fitted onto the fixed end 11 or the movable end 12 of the outside micrometer 1 until each steel ball 2 abuts against the end face of the fixed end 11 or the movable end 12, which can prevent the steel ball 2 from forming a gap with the fixed end 11 or the movable end 12 and affecting the subsequent measurement.
[0031] Next, the workpiece 100 to be measured is placed on the worktable, and the movable end 12 is screwed on to insert the two steel balls 2 into the two parallel spiral grooves 101 on the workpiece 100, until each steel ball 2 is quickly clamped at the bottom of the corresponding spiral groove 101. At this time, one side of the steel ball 2 is in close contact with the bottom of the spiral groove 101, and the other side of the steel ball 2 is in contact with the end face of the fixed end 11 or the movable end 12. That is, the workpiece 100 and the two steel balls 2 are precisely clamped between the movable end 12 and the fixed end 11. Finally, the outer micrometer 1 is read to obtain accurate dimensional data. The distance between the two parallel spiral grooves 101 is calculated by subtracting the diameter of the two steel balls 2 from the dimensional data. This is the distance between the bottoms of the two parallel spiral grooves 101, which is the distance between the two parallel spiral grooves 101, resulting in high measurement accuracy.
[0032] In other words, the present invention provides a measuring fixture for the spacing of parallel spiral grooves, which can conveniently measure the spacing between two parallel spiral grooves 101 on the workpiece 100 to be measured, with high measurement accuracy.
[0033] It is easy to understand that the fixed end 11 and the movable end 12 of the outside micrometer 1, together with the bushing 3, can be arranged on both sides of the workpiece 100 to be measured, and each steel ball 2 can be closely attached to the bottom of the corresponding spiral groove 101 at any position, so that the measurement of any position on the spiral groove 101 can be realized without being affected by the end face of the workpiece 100 to be measured.
[0034] Furthermore, the axial length of the bushing 3 corresponding to the fixed end 11 is less than the length L from the end face of the fixed end 11 to the handle 13 of the outside micrometer 1 plus the radius of the steel ball 2, to prevent the bushing 3 from being too long and thus preventing the steel ball 2 from simultaneously contacting the workpiece 100 to be measured and the fixed end 11. Similarly, the axial length of the bushing 3 corresponding to the movable end 12 is less than the length from the end face of the movable end 12 to the handle 13 of the outside micrometer 1 plus the radius of the steel ball 2, to prevent the bushing 3 from being too long and thus preventing the steel ball 2 from simultaneously contacting the workpiece 100 to be measured and the movable end 12. Moreover, the measuring range of the outside micrometer 1 is greater than the distance between the two parallel spiral grooves 101 plus twice the diameter of the steel ball 2.
[0035] For example, the workpiece 100 to be tested has four spiral grooves 101, which are parallel and spaced apart in pairs.
[0036] See also Figures 3-5 Each bushing 3 has an annular notch 32 on the outer periphery of one end, which is used to avoid the workpiece 100 to be tested.
[0037] It is easy to understand that the annular notch 32 on the side of the bushing 3 facing the workpiece 100 can reduce the outer diameter and avoid interference between the bushing 3 and the workpiece 100 during the measurement process due to the excessive outer diameter on the side of the bushing 3 facing the workpiece 100.
[0038] Furthermore, in the axial direction of the bushing 3, the thickness of the annular notch 32 is equal to the thickness of the inner flange 31, which facilitates machining.
[0039] In one implementation of the present invention, the inner peripheral wall of the inner flange 31 is tapered, and the diameter of the inner flange 31 decreases sequentially from one end of the bushing 3 to the other end. The tapered structure of the inner flange 31 facilitates the securing of the steel ball 2, increases the contact area, and prevents the sides of the inner flange 31 from scratching the steel ball 2.
[0040] In this embodiment, one bushing 3 is on the movable end 12, and the other bushing 3 is sleeved on the fixed end 11. In the axial direction of the bushing 3, the length of one bushing 3 is greater than the length of the other bushing 3.
[0041] It is easy to understand that, in the axial direction, the length of the movable end 12 is greater than the length of the fixed end 11. Therefore, the length of the bushing 3 corresponding to the movable end 12 is greater than the length of the bushing 3 corresponding to the fixed end 11. This can increase the contact area between the bushing 3 corresponding to the movable end 12 and the movable end 12, increase the reliability of the bushing 3 being fitted on the movable end 12, and reduce the risk of falling off.
[0042] In addition, the inner circumferential wall of the other end of each bushing 3 has a rounded corner, which facilitates the quick fitting of the bushing 3 to the fixed end 11 or the movable end 12.
[0043] For example, the outer peripheral wall of each bushing 3 has anti-slip threads, thereby increasing friction and making it easier for technicians to hold and fit it onto the fixed end 11 or the movable end 12.
[0044] Figure 6 This is a flowchart of a method for measuring the spacing of parallel helical grooves provided in an embodiment of the present invention, as shown below. Figure 6 As shown, the measurement method is based on the aforementioned measuring fixture for the spacing of parallel spiral grooves, and the measurement method includes...
[0045] S1. Insert each steel ball 2 into the bushing 3 from the other end of the corresponding bushing 3 and lock it in the corresponding inner flange 31.
[0046] S2. Place the two bushings 3 onto the fixed end 11 or the movable end 12 of the outside micrometer 1, until each steel ball 2 abuts against the end face of the fixed end 11 or the movable end 12.
[0047] S3. Place the workpiece 100 to be tested on the workbench and screw the movable end 12 so that the two steel balls 2 are respectively inserted into the two parallel spiral grooves 101 on the workpiece 100 to be tested, until each steel ball 2 is stuck at the bottom of the corresponding spiral groove 101.
[0048] S4. Take a reading from the outer micrometer 1 to obtain the dimensional data. Calculate the distance between the two parallel spiral grooves 101 using the dimensional data and the diameter of the steel ball 2.
[0049] This invention provides a method for measuring the spacing between parallel spiral grooves, which can conveniently measure the spacing between two parallel spiral grooves 101 on the workpiece 100 to be measured, with high measurement accuracy.
[0050] In this embodiment, before step S2, the measurement method further includes: Grease is applied to the outer peripheral wall of the fixed end 11, the outer peripheral wall of the movable end 12, and the inner peripheral walls of the two bushings 3.
[0051] In the above real-time mode, the grease can increase the fitting strength of the bushing 3 on the fixed end 11 or the movable end 12, and prevent the bushing 3 from falling off the fixed end 11 or the movable end 12.
[0052] In addition, after step S4, this measurement method further includes: Repeat steps S1-S4 to obtain the distance between the two parallel spiral grooves 101 at different positions along the axial direction of the workpiece 100 to be tested, and calculate the average value.
[0053] In the above embodiment, by measuring the distance between the two parallel spiral grooves 101 multiple times at different positions and calculating the average value, the measurement accuracy can be further increased, the reliability can be improved, and the error caused by reading or operation can be effectively reduced.
[0054] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A measuring fixture for the spacing of parallel helical grooves, characterized in that, The measuring fixture includes an outside micrometer (1), two steel balls (2) and two bushings (3); The diameter of each of the steel balls (2) is smaller than the inner diameter of the corresponding bushing (3), and each of the steel balls (2) is used to be inserted into the corresponding spiral groove (101) of the workpiece to be tested (100); Each bushing (3) has an inner flange (31) on one end of its inner peripheral wall. The inner diameter of the inner flange (31) is smaller than the diameter of the steel ball (2). The inner flange (31) is used to hold the corresponding steel ball (2). The other end of each bushing (3) is detachably fitted onto the fixed end (11) or movable end (12) of the outside micrometer (1) so that the end face of the fixed end (11) or the movable end (12) abuts against the corresponding steel ball (2).
2. The measuring fixture for the spacing of parallel spiral grooves according to claim 1, characterized in that, Each bushing (3) has an annular notch (32) on the outer periphery of one end, which is used to avoid the workpiece (100) to be tested.
3. The measuring fixture for the spacing of parallel spiral grooves according to claim 2, characterized in that, In the axial direction of the bushing (3), the thickness of the annular notch (32) is equal to the thickness of the inner flange (31).
4. The measuring fixture for the spacing of parallel spiral grooves according to claim 1, characterized in that, The inner peripheral wall of the inner flange (31) is tapered, and the diameter of the inner flange (31) decreases sequentially from the other end of the bushing (3) to one end of the bushing (3).
5. The measuring fixture for the spacing of parallel spiral grooves according to claim 1, characterized in that, One of the bushings (3) is on the movable end (12), and the other bushing (3) is fitted on the fixed end (11). In the axial direction of the bushings (3), the length of one bushing (3) is greater than the length of the other bushing (3).
6. A measuring fixture for the spacing of parallel spiral grooves according to any one of claims 1-5, characterized in that, The inner circumferential wall of the other end of each bushing (3) has a rounded corner.
7. A measuring fixture for the spacing of parallel spiral grooves according to any one of claims 1-5, characterized in that, Each bushing (3) has an anti-slip thread on its outer peripheral wall.
8. A method for measuring the spacing of parallel helical grooves, characterized in that, The measurement method is based on a measuring fixture for parallel spiral groove spacing as described in any one of claims 1-7, and the measurement method includes: S1. Insert each of the steel balls (2) into the bushing (3) from the other end of the corresponding bushing (3) and lock them into the corresponding inner flange (31); S2. Place the two bushings (3) onto the fixed end (11) or movable end (12) of the outside micrometer (1) respectively, until each of the steel balls (2) abuts against the end face of the fixed end (11) or the movable end (12); S3. Place the workpiece to be tested (100) on the workbench and screw the movable end (12) so that the two steel balls (2) are respectively inserted into the two parallel spiral grooves (101) on the workpiece to be tested (100) until each steel ball (2) is stuck at the bottom of the corresponding spiral groove (101). S4. Take a reading on the outside micrometer (1) to obtain the size data, and calculate the distance between the two parallel spiral grooves (101) using the size data and the diameter of the steel ball (2).
9. A method for measuring the spacing of parallel helical grooves according to claim 8, characterized in that, Prior to step S2, the measurement method further includes: The outer peripheral wall of the fixed end (11), the outer peripheral wall of the movable end (12), and the inner peripheral walls of the two bushings (3) are all coated with grease.
10. A method for measuring the spacing of parallel helical grooves according to claim 8, characterized in that, After step S4, the measurement method further includes: Repeat steps S1-S4 to obtain the distance between the two parallel spiral grooves (101) at different positions along the axial direction of the workpiece (100) to be tested, and calculate the average value.