Method for measuring radius of generatrix of outer diameter of asymmetric spherical roller

Abstract

The invention discloses a method for measuring the radius of an outer diameter generatrix of an asymmetric spherical roller. The method comprises the following steps: selecting two cylindrical rollers of which the diameters are equal to those of a measured spherical roller; the two cylindrical rollers are arranged in the V-shaped groove; a to-be-measured spherical roller is placed in the V-shaped groove, one end face of the to-be-measured spherical roller is in sufficient and firm contact with any end face of one cylindrical roller, any end face of the other cylindrical roller is in sufficient and firm contact with the other end face of the to-be-measured spherical roller, and the axis of the spherical roller is limited through the axis of the cylindrical rollers. The axis of the measured spherical roller is parallel to the moving direction of the contourgraph probe; a contourgraph is used for measuring the spherical generatrix contour of the maximum diameter position, the contour passes through the maximum diameter position and is parallel to the axis of the measured spherical roller, and the radius of the contour is the radius of the outer diameter generatrix of the measured spherical roller. The problem of poor measurement reproducibility when a contourgraph is used for measuring the radius of the generatrix of the asymmetric spherical roller is solved.

Description

Technical Field

[0001] The invention relates to a measuring method, in particular to a method for measuring the outer diameter generatrix radius of an asymmetric spherical roller, belonging to the technical field of geometric measurement. Background Art

[0002] The outer diameter generatrix of the asymmetric spherical roller is an arc with a certain radius, and the center of the arc is not located on the geometric mid-plane of the roller height, but is offset from the mid-plane by a certain distance, see Figure 1 As shown. The radius of the roller outer diameter generatrix directly affects the contact state between the roller and the outer ring and inner ring, and directly affects the bearing rotation accuracy and bearing life. Therefore, it is particularly important to accurately measure the radius value of the roller outer diameter generatrix. For the measurement of the roller outer diameter generatrix radius, a special template can be used to qualitatively determine whether the curvature radius is qualified by the light gap method. However, this method relies on the experience of the measurement personnel. Different measurement personnel will have completely different judgment results for the same workpiece, and this method is affected by human factors. At present, with the continuous development of the manufacturing technology of the profiler, the continuous improvement of the measurement accuracy and software algorithm, using a profiler to measure the convexity of the outer diameter generatrix is ​​a relatively common method.

[0003] However, when using the profiler for measurement, it was found that the reproducibility of the roller radius measurement results was poor, and the differences in the measurement results each time were large. In particular, the reproducibility of the radius of the outer diameter generatrix of the asymmetric spherical roller is even worse. After repeated tests, it was found that due to the particularity of the spherical roller structure, when the spherical roller is placed in a V-groove, it is in point contact with the V-groove, not line contact. In the V-groove, the axis of the roller will be deflected to a certain extent, and it is not parallel to the direction of movement of the profiler probe, resulting in the measured outer diameter generatrix not coinciding with the theoretical outer diameter generatrix, and there is a certain deflection angle. At this time, the measured outer diameter generatrix is ​​not the outer diameter generatrix at the maximum diameter position and parallel to the roller axis. Figure 2 As shown. Since the degree of non-parallelism or deflection between the roller axis and the moving direction of the measuring needle is different each time the roller is clamped, the outer diameter generatrix arc measured each time is different. Therefore, the outer diameter generatrix radius analyzed and evaluated each time will be different, resulting in poor reproducibility of the measured outer diameter generatrix radius.

[0004] Therefore, it is necessary to develop a new method to improve the measurement accuracy of the outer diameter generatrix radius. Summary of the invention

[0005] The present invention overcomes the shortcomings of the prior art and provides a method for measuring the outer diameter generatrix radius of an asymmetric spherical roller, so as to solve the problem of poor measurement reproducibility and low accuracy when using a profilometer to measure the outer diameter generatrix radius of an asymmetric spherical roller.

[0006] A method for measuring the outer diameter generatrix radius of an asymmetric spherical roller comprises:

[0007] S1. Select two cylindrical rollers with the same diameter as the spherical roller to be measured;

[0008] S2. Place two cylindrical rollers in the V-groove and reserve the end faces for later use;

[0009] S3, positioning one of the cylindrical rollers, placing the spherical roller to be measured in the V-groove, making one end face of the spherical roller to be measured fully and firmly contact with any end face of one of the cylindrical rollers, and any end face of the other cylindrical roller fully and firmly contact with the other end face of the spherical roller to be measured, then positioning the other cylindrical roller, limiting the axis of the spherical roller by the axis of the cylindrical roller, and ensuring that the axis of the spherical roller to be measured is parallel to the direction of movement of the profilometer stylus;

[0010] S4. Use a profilometer to measure the spherical generatrix profile at the maximum diameter position. This profile passes through the maximum diameter position and is parallel to the axis of the spherical roller being measured. The radius of the arc profile is the radius of the outer diameter generatrix of the spherical roller being measured.

[0011] Compared with the prior art, the present invention has the following beneficial effects:

[0012] This application uses two cylindrical rollers as measuring accessories. When the cylindrical roller is placed in a V-groove, it is in line contact with both sides of the V-groove, ensuring that the axis of the roller is parallel to the direction of movement of the measuring needle. From the geometric structure of the cylindrical roller, it can be seen that the axis of the cylindrical roller is perpendicular to the end faces on both sides. The end faces of the cylindrical roller are used as auxiliary positioning surfaces to contact the end faces of the spherical roller being measured. From the geometric relationship, it can be seen that as long as the end faces are firmly combined, the axis of the spherical roller can be guaranteed to be parallel to the direction of the profilometer measurement. The axis of the spherical roller is limited by the axis of the cylindrical roller, effectively avoiding the occurrence of spherical roller deviation.

[0013] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments: BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a schematic diagram of an existing asymmetric spherical roller;

[0015] Figure 2 It is a schematic diagram of the theoretical outer diameter generatrix and the measured outer diameter generatrix in the traditional measurement technology;

[0016] Figure 3 It is a schematic diagram of the perpendicular relationship between the end face of the cylindrical roller and the axis;

[0017] Figure 4 Schematic diagram of a cylindrical roller fixing a spherical roller in this method;

[0018] Figure 5 Schematic diagram of the measurement setup incorporated into the method. DETAILED DESCRIPTION

[0019] The embodiments of the technical solution of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that, unless otherwise specified, the technical terms or scientific terms used in this application should have the common meanings understood by technicians in the field to which this application belongs.

[0020] From the working principle of the profiler measurement, it can be known that in order to accurately measure the outer diameter generatrix radius of the spherical roller, it is necessary to ensure that the outer diameter generatrix axis of the roller is parallel to the moving direction of the profiler probe. In this way, the arc measured by the profiler passes through the maximum diameter position in the Y-axis direction and is parallel to the moving direction of the profiler probe.

[0021] When measuring with a profilometer, the roller being measured is usually placed in a V-groove. Since the outer diameter generatrix of the roller being measured is a spherical structure, when it is placed in the V-groove, the spherical roller is in point contact with both sides of the V-groove, causing the axis of the roller being measured to deviate from the moving direction of the profilometer probe. Each time it is placed, the degree of deflection is relatively random, resulting in large differences in each measurement result.

[0022] In view of this, through experiments and in combination with the structural characteristics of spherical rollers, a method for measuring the outer diameter generatrix radius of an asymmetric spherical roller using a cylindrical roller as a measuring accessory was developed, and the method comprises:

[0023] S1. Select two cylindrical rollers with the same diameter as the spherical roller to be measured;

[0024] S2. Place two cylindrical rollers in the V-groove and reserve the end faces for later use;

[0025] S3, positioning one of the cylindrical rollers, placing the spherical roller to be measured in the V-groove, making one end face of the spherical roller to be measured fully and firmly contact with any end face of one of the cylindrical rollers, and any end face of the other cylindrical roller fully and firmly contact with the other end face of the spherical roller to be measured, then positioning the other cylindrical roller, limiting the axis of the spherical roller by the axis of the cylindrical roller, and ensuring that the axis of the spherical roller to be measured is parallel to the direction of movement of the profilometer stylus;

[0026] S4. Use a profilometer to measure the spherical generatrix profile at the maximum diameter position. The profile passes through the maximum diameter position and is parallel to the axis of the spherical roller being measured. The radius of the arc profile is the radius of the outer diameter generatrix of the spherical roller being measured.

[0027] Embodiment 1,

[0028] Select two cylindrical rollers with diameters approximately equal to the spherical roller being measured;

[0029] Fix one of the cylindrical rollers in the V-groove and use hot melt adhesive to firmly bond the cylindrical roller in the V-groove;

[0030] The spherical roller to be measured is placed in the V-groove, and its end face is in full and firm contact with the end face of the cylindrical roller 1, and the contact is surface-to-surface. The axis of the spherical roller to be measured is indirectly guaranteed to be parallel to the direction of movement of the profilometer probe through the axis of the cylindrical roller 1. Then another cylindrical roller 2 is also placed in the V-groove, in full contact with the other end face of the spherical roller, and the cylindrical roller is firmly fixed with plasticine. The cylindrical roller 2 is only used to fix the spherical roller to be measured to prevent it from moving during measurement. The profilometer is used to measure the spherical generatrix profile at the maximum diameter position, which passes through the maximum diameter position and is parallel to the axis of the spherical roller. The radius R of the profile is the radius of the outer diameter generatrix of the spherical roller to be measured.

[0031] This method uses two cylindrical rollers as measuring accessories, and the axis of the spherical roller is limited by the axis of the cylindrical roller. Since the cylindrical roller is placed in the V-groove, it is in line contact with both sides of the V-groove, which ensures that the axis of the roller is parallel to the moving direction of the probe. From the geometric structure of the cylindrical roller, it can be seen that the axis of the cylindrical roller is perpendicular to the end faces on both sides, as shown in Figure 2. Figure 4 As shown. The end face of the cylindrical roller is used as an auxiliary positioning surface to contact the end face of the spherical roller to be measured. From the geometric relationship, it can be seen that as long as the end faces are firmly combined, the axis of the spherical roller can be guaranteed to be parallel to the direction measured by the profiler, effectively avoiding the deviation of the spherical roller.

[0032] Example 2, reference Figure 3 , Figure 4 and Figure 5 ,

[0033] Select a certain type of spherical roller, the curvature of the outer diameter generatrix is ​​45.1±0.05mm. Repeat the clamping, and use the above-mentioned method to measure the outer diameter generatrix radius of the asymmetric spherical roller, and measure it 10 times.

[0034] The measurement results are shown in the table below:

[0035]

[0036] From the 10 measurement results, it can be seen that the minimum radius measurement result is 45.1348mm, the maximum radius measurement result is 45.1532mm, and the difference between the maximum and minimum values ​​is 0.0184mm, which accounts for about one fifth of the tolerance zone and meets the accuracy requirement. The method for measuring the outer diameter generatrix radius of the spherical roller proposed in this embodiment is feasible.

[0037] The present invention has been disclosed as above with preferred implementation cases, but it is not used to limit the present invention. Any technician familiar with the profession can make slight changes or modifications to equivalent implementation cases with equivalent changes by using the above-disclosed structures and technical contents without departing from the scope of the technical solution of the present invention, which still fall within the scope of the technical solution of the present invention.

Claims

1. A method for measuring the outer diameter generatrix radius of an asymmetric spherical roller, characterized in that: The method comprises: S1. Select two cylindrical rollers with the same diameter as the spherical roller to be measured; S2. Place two cylindrical rollers in the V-groove and reserve the end faces for later use; S3, positioning one of the cylindrical rollers, placing the spherical roller to be measured in the V-groove, making one end face of the spherical roller to be measured fully and firmly contact with any end face of one of the cylindrical rollers, and any end face of the other cylindrical roller fully and firmly contact with the other end face of the spherical roller to be measured, then positioning the other cylindrical roller, limiting the axis of the spherical roller by the axis of the cylindrical roller, and ensuring that the axis of the spherical roller to be measured is parallel to the direction of movement of the profilometer stylus; S4. Use a profilometer to measure the spherical generatrix profile at the maximum diameter position. The profile passes through the maximum diameter position and is parallel to the axis of the spherical roller being measured. The radius of the profile is the radius of the outer diameter generatrix of the spherical roller being measured.

2. A method for measuring the outer diameter generatrix radius of an asymmetric spherical roller according to claim 1, characterized in that: In step S3, one of the cylindrical rollers is bonded to the V-groove with hot melt adhesive to achieve positioning.

3. The method for measuring the outer diameter generatrix radius of an asymmetric spherical roller according to claim 1, characterized in that: In step S3, another cylindrical roller is positioned in the V-shaped groove using plasticine.

4. The method for measuring the outer diameter generatrix radius of an asymmetric spherical roller according to claim 1, characterized in that: In step S3, the two end faces of the spherical roller to be measured are in surface contact with the end faces of the two cylindrical rollers respectively.

5. The method for measuring the outer diameter generatrix radius of an asymmetric spherical roller according to claim 1, characterized in that: The outer diameter generatrix curvature of the measured spherical roller is 45.1±0.05 mm, the minimum radius measurement value is 45.1348 mm, the maximum radius measurement value is 45.1532 mm, and the difference between the maximum and minimum values ​​is 0.0184 mm.

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