Cross cylindrical roller bearing ring raceway angle measuring method
By using the steel ball needle of the dial gauge to measure the raceway diameter of the cross cylindrical roller bearings, and combined with iterative solution of geometric relationships, the problem of raceway angle measurement accuracy and inefficiency in the prior art is solved, and efficient and precise raceway angle detection is achieved.
Patent Information
- Application Number
- CN202411682753.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-22
- Publication Date
- 2025-04-04
AI Technical Summary
The prior art is difficult to accurately measure the raceway angle of crossed cylindrical roller bearings, resulting in limited measurement accuracy and inefficiency, which cannot meet the needs of mass production.
The steel ball needle using a dial gauge measures the diameter of the raceway inside the bearing and combines iterative solution to obtain the raceway angle and deflection angle.
It improves the accuracy and efficiency of raceway angle measurement, and can quickly and accurately detect the raceway angle of small cross cylindrical roller bearings to meet the needs of mass production.
Smart Images
Figure CN119756129A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of bearing detection, and in particular to a method for measuring a raceway angle of a crossed cylindrical roller bearing ring. Background Art
[0002] There are two mutually perpendicular raceways inside the crossed cylindrical roller bearings. The cylindrical rollers are arranged perpendicularly and crosswise at 90 degrees in the two raceways, so they can bear axial loads, radial loads and overturning moments. This type of bearing has a compact structure and is easy to install. It also has the characteristics of high rigidity, high load capacity and high precision. It is widely used in industrial robot joints or rotating parts, machining center rotary tables, precision instrument turntables, etc.
[0003] The two mutually perpendicular raceways of the crossed cylindrical roller bearing are arranged on the inner ring and outer ring of the bearing respectively. Theoretically, they are designed to be mutually perpendicular at 90°. The mutually perpendicular raceway angle of 90° is the optimal value, which can reduce the friction torque, improve the bearing's load capacity and limit speed, etc. However, due to the existence of processing errors in the actual processing process, the mutually perpendicular raceway angle will inevitably deviate from 90°. Whether it is a positive deviation or a negative deviation from 90°, it will affect the various performances of the crossed cylindrical roller bearing. Therefore, it is necessary to design a tolerance for the raceway angle to reduce the impact on the bearing performance. At present, there are few methods for accurately measuring the raceway angle of crossed cylindrical roller bearings. The commonly used method is to collect coordinate points along the two raceways through a profiler, and then fit the contour curve through software, analyze and calculate the raceway angle. This method is affected by the raceway length and the accuracy of coordinate point collection, and the measurement accuracy of the raceway angle is affected to a certain extent. In addition, this method has low measurement efficiency and cannot meet the requirements of mass production. Aiming at the structural characteristics of mutually perpendicular raceways of crossed cylindrical roller bearings, the present invention designs auxiliary measurement tooling and proposes a method for measuring the raceway angle of small crossed roller bearings. While ensuring detection accuracy, the method improves detection efficiency and meets the needs of efficient and precise detection of bearings in mass production. Summary of the invention
[0004] The purpose of the present invention is to provide a method for measuring the raceway angle of a crossed cylindrical roller bearing ring, so as to achieve the purpose of quickly and accurately measuring the raceway angle of small crossed cylindrical roller bearings in mass production, improve production efficiency and reduce production costs.
[0005] The technical solution adopted by the present invention is: a method for measuring the angle of a raceway of a cross cylindrical roller bearing ring, using a micrometer with a steel ball as the needle to measure the diameter of the inner ring raceway of the bearing, comprising the following steps:
[0006] Adjust the two steel balls with a diameter of dwx of the micrometer to be tangent to the two raceway side walls of the inner ring of the bearing respectively, and obtain the reading dwx2 of the micrometer;
[0007] Move the inner ring of the bearing axially relative to the micrometer by a distance A, adjust the two steel balls with a diameter of dwx of the micrometer to be tangent to only one side of the raceway side wall, and obtain the reading of the micrometer dwx2p;
[0008] Replace the micrometer or the steel ball of the micrometer, adjust the two steel balls with a diameter of dwz to be tangent to the two raceway side walls of the inner ring of the bearing, and obtain the reading dwz2 of the micrometer; where dwx≠dwz;
[0009] Substitute the above readings into the following two equations for iterative solution to obtain the raceway angle α and raceway skew angle β of the crossed cylindrical roller bearing:
[0010] (dwz2-dwx2+dwz-dwx)×sin(α / 2)=(dwz-dwx)×cos(β)
[0011] dwx2p=dwx2+2×A / tan (α / 2+β)
[0012] Where: α is a positive angle value, β is a positive angle, a negative angle or 0°.
[0013] As a preferred solution, when measuring the diameter of the bearing inner ring raceway, select the radial line of the bearing inner ring perpendicular to the center connection line of the two steel balls as the direction to move the bearing inner ring multiple times, record the reading of the micrometer after each movement, and take the maximum value as the effective reading.
[0014] As a preferred solution, when measuring the diameter of the bearing inner ring raceway, the bearing inner ring is rotated multiple times along its circumference, and the reading of the micrometer is recorded after each rotation, and the average value is taken as the effective reading.
[0015] As a preferred solution, when obtaining the readings dwx2 and dwz2, adjust the position of the inner ring of the bearing along the axial direction until there is no shaking between the inner ring of the bearing and the two steel balls in the axial direction, and then obtain the reading of the micrometer.
[0016] As a preferred solution, before obtaining the reading of the micrometer, a force is applied to one end face of the inner ring of the bearing in a direction perpendicular to the connecting line of the centers of the two steel balls to keep the inner ring of the bearing stable.
[0017] As a preferred solution, a limiter is used to apply a force to keep the inner ring of the bearing stable, and the limiter has three contact pins that contact the end surface of the inner ring of the bearing.
[0018] As a preferred solution, the limiting member includes a fixed seat, a sliding seat slidably disposed on the fixed seat, a contact pin on the sliding seat, and a length measuring instrument disposed on the fixed seat and capable of detecting the position of the sliding seat.
[0019] As a preferred solution, the micrometer uses a steel ball with high sphericity as a needle, and the diameters of the two steel balls on the same micrometer are the same.
[0020] Compared with the prior art, the present invention has the following beneficial effects:
[0021] The present invention uses the steel ball needle of the micrometer to measure the diameter to convert the size of the raceway angle and the size of the raceway deflection angle. The overall test method is simple, and the measurement efficiency and accuracy are improved. The method is used to judge the raceway accuracy and can guide actual processing and production, which is conducive to processing a more accurate raceway angle close to 90° perpendicular to each other, thereby reducing the friction torque, improving the bearing capacity and limit speed of the bearing, etc. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0023] Figure 1 This is a schematic diagram of measuring the raceway diameter using an instrument with a steel ball as the tip;
[0024] Figure 2 It is a schematic diagram of the contact between the steel ball and the two raceways when the raceway angle is α;
[0025] Figure 3 It is a schematic diagram of the contact between the steel ball and the two raceways when the raceway angle is α and the raceway center deflection angle is β;
[0026] Figure 4 It is a schematic diagram of the use of the limiter;
[0027] Figure 5 This is a schematic diagram of the contact between the steel ball and the raceway after the inner ring of the bearing is raised to a height of A;
[0028] Figure 6 This is an enlarged schematic diagram of a partial cross-section of the bearing inner ring. DETAILED DESCRIPTION
[0029] The present invention is described in detail below by way of exemplary embodiments. However, it should be understood that, without further description, elements, structures and features in one embodiment may also be beneficially combined in other embodiments.
[0030] It should be noted that: unless otherwise defined, the technical terms or scientific terms used in this document shall have the usual meanings understood by people with ordinary skills in the field to which the invention belongs. The words "one", "an" or "the" and the like used in the patent application specification and claims of the present invention do not express quantity restrictions, but indicate the existence of at least one; the words "first", "second" and "third" used in this document shall not be regarded as restrictions on the order of components, but are only used to distinguish different components; words such as "include" or "comprise" and the like indicate that the elements or objects appearing before "include" or "comprise" include the elements or objects listed after "include" or "comprise" and their equivalents, but do not exclude other elements or objects with the same function.
[0031] In order to more clearly describe the method for measuring the raceway angle of the crossed cylindrical roller bearing ring, Figure 1-6 Describe this embodiment:
[0032] It is known that the actual angle of the inner ring or outer ring raceway of the crossed cylindrical roller bearing is about 90°, that is, the angle between the two raceway side walls 401 of the raceway 4 is 90°, and the steel ball 2 is placed between the angles of the raceway 4. According to the definition of the tangent of a circle, the line connecting the contact point of the steel ball 2 with the raceway and the center of the steel ball is 90° perpendicular to the raceway. In this way, the two points at which the steel ball contacts the raceway of the crossed cylindrical roller bearing and the line connecting the bottom of the raceway groove and the center of the steel ball form a parallelogram, in which two 90° angles are diagonal to each other.
[0033] By using a micrometer 1 (where the needle is a steel ball of diameter D), a reading size can be measured. This reading size can be considered as a related size of the bearing raceway size, which is related to the size Dw of the steel ball, the raceway groove bottom diameter di, and the raceway angle α.
[0034] Use two micrometers 1 for measurement (the needles are steel balls with different diameters), then two readings can be read out. The relationship between the raceway angle α and the skew angle β can be deduced by conversion of the two dimensions. After raising the end face of the bearing, use one of the micrometers to read the measured value of the instrument under this condition. The reading has a geometric relationship with the single-sided raceway angle and the raising dimension. Substitute the relationship between the raceway angle α and the skew angle β into the formula to obtain the raceway angle α and the skew angle β.
[0035] The method for measuring the raceway angle of a crossed cylindrical roller bearing ring uses a micrometer with a steel ball as the needle to measure the diameter of the bearing inner ring raceway, and then converts the size of the raceway angle and the size of the raceway deflection angle. The micrometer uses a high-sphericity steel ball as the needle and needs to have high precision. During the measurement process, the steel ball does not deform or tilt, and the diameters of the two steel balls on the same micrometer are the same.
[0036] The design process is as follows:
[0037] When the gauge needle is a steel ball, the reading of the gauge is related to the raceway groove bottom diameter di, the gauge needle steel ball size, the raceway angle and the raceway deflection angle. When calculating, first assume that the raceway angle is α and the raceway has no deflection, and then combine Figure 2 The geometric relationship between , we can get equation 1 and equation 2;
[0038]
[0039] Where dwx1 is the reading measured by the micrometer using a steel ball with a diameter of dwx when the raceway is not tilted;
[0040] dwz1 is the reading measured by the micrometer using a steel ball with a diameter of dwz when the raceway is not tilted;
[0041] Combination Figure 3 , when the raceway angle is α and the raceway deflection angle is β, it can be considered that the ideal raceway with a raceway angle of α and no raceway deflection is rotated toward the end face by an angle of β with the groove bottom as the rotation center. From this geometric relationship, equation 3 can be obtained. Substituting equation 1 into equation 3, equation 4 can be obtained. Similarly, equation 5 can be obtained.
[0042]
[0043] dwx2 is the reading measured by the micrometer using a steel ball with a diameter of dwx when the raceway is tilted;
[0044] dwz2 is the reading measured by the micrometer using a steel ball with a diameter of dwz when the raceway is tilted;
[0045] Combining equations 4 and 5, we can get the numerical relationship between the raceway angle and the raceway deflection angle;
[0046] (dwz2-dwx2+dwz-dwx)×sin(α / 2)=(dwz-dwx)×cos(β) (6)
[0047] Use bearing parts Figure 4 The limiter shown moves along the axis direction A (in the figure, the dotted line tip and the fulcrum indicate the position before the movement, and the solid line tip and the fulcrum indicate the position after the movement), as shown in FIG. Figure 5 , the steel ball tip and the fulcrum move radially to the corresponding position in the direction of the raceway angle α / 2-β or α / 2+β, and the specific value is A / tan(α / 2-β) or A / tan(α / 2+β). At this time, the result measured by the instrument is dwx2p. The relationship between the measurement result and the axial movement distance of the steel ball and the raceway angle is shown in Formula 7;
[0048] dwx2p=dwx2+2×A / tan(α / 2+β) (7)
[0049] Wherein: α is a positive angle value; β is a positive angle, a negative angle or 0°. When β is a positive angle, it means that the direction of the raceway deflection is the same as the direction of the axial movement of the bearing inner ring. When β is a negative angle, it means that the direction of the raceway deflection is opposite to the direction of the axial movement of the bearing inner ring.
[0050] The specific measurement includes the following steps:
[0051] Step 1: Read Figure 3 As shown in the left figure, adjust the two steel balls 5 with a diameter of dwx of the micrometer 1 to be tangent to the two raceway side walls of the inner ring of the bearing (each steel ball 5 is in contact with the raceway side walls on both sides, and the contact position or tangent point between the two forms a steel ball fulcrum 6), and obtain the reading dwx2 of the micrometer 1;
[0052] Step 2: Read Figure 4 or Figure 5 , move the inner ring of the bearing axially relative to the micrometer 1 by a distance A, and adjust the two steel balls 5 with a diameter of dwx of the micrometer 1 to be tangent to only one side of the raceway side wall (at Figure 4 or Figure 5 In the orientation shown, the inner ring of the bearing moves to the right, and the steel ball 5 only contacts the left side wall of the raceway, and does not contact the right side wall of the raceway. The contact position or tangent point of the two forms a steel ball fulcrum 9), and the reading of the micrometer dwx2p is obtained;
[0053] Step 3: Read Figure 3 As shown in the right figure, replace the micrometer 1 or the steel ball of the micrometer 1, adjust the two steel balls 7 with a diameter of dwz to be tangent to the two raceway side walls of the inner ring of the bearing (each steel ball 7 contacts the raceway side walls on both sides, and the contact position or tangent point between the two forms a steel ball fulcrum 8), and obtain the reading dwz2 of the micrometer 1; where dwx≠dwz;
[0054] Substituting the above readings into equations (6) and (7) for iterative solution, a unique solution can be obtained, that is, the raceway angle α and raceway skew angle β of the crossed cylindrical roller bearing can be obtained.
[0055] In the above measurement method, the measurement error can be reduced by:
[0056] (1) When measuring the diameter of the raceway 4 of the inner ring 3 of the bearing, select the radial line of the inner ring 3 of the bearing perpendicular to the center connecting line of the two steel balls 2 as the direction to move the inner ring 3 of the bearing multiple times, record the reading of the micrometer 1 after each movement, and take the maximum value as the effective reading;
[0057] (2) When measuring the diameter of the raceway 4 of the inner ring 3 of the bearing, rotate the inner ring 3 of the bearing several times along its circumference, record the reading of the micrometer 1 after each rotation, and take the average value as the effective reading;
[0058] (3) When obtaining the readings dwx2 and dwz2, adjust the position of the bearing inner ring 3 along the axial direction until there is no shaking between the bearing inner ring 3 and the two steel balls 2 in the axial direction, and then obtain the reading of the micrometer 1.
[0059] During the measurement, the stability of the inner ring 3 of the bearing to be measured needs to be maintained:
[0060] See also Figure 4 Before obtaining the reading of the micrometer 1, a force is applied to one end face of the bearing inner ring 3 in a direction perpendicular to the center connecting line of the two steel balls 2 by using a limiter to keep the bearing inner ring 3 stable;
[0061] Specifically, the limit member includes a fixed seat 10, a sliding seat 11 slidably arranged on the fixed seat 10, a feeler pin 12 on the sliding seat 11, and a length measuring instrument 13 arranged on the fixed seat 10 and capable of detecting the position of the sliding seat 11. There are at least three feelers 12 distributed at equal angles for direct contact with the end face of the bearing inner ring 3. The length measuring instrument 13 adopts a high-precision measuring instrument, and its measuring end can move with the sliding seat 11, so as to obtain an accurate A value.
[0062] The parts not described in detail in the above embodiments are prior art.
[0063] It should be noted that although the present invention is described by the above embodiments, the present invention may also have other various embodiments. Without departing from the spirit and scope of the present invention, it is obvious that those skilled in the art may make various corresponding changes and deformations to the present invention, but these changes and deformations should all fall within the scope of protection of the appended claims of the present invention and their equivalents.
Claims
1. A method for measuring the raceway angle of a crossed cylindrical roller bearing ring, characterized in that: Use a micrometer with a steel ball as the needle to measure the diameter of the inner ring raceway of the bearing. The following steps are involved: Adjust the two steel balls of the dial gauge with a diameter of dwx to be tangent to the two groove side walls of the inner ring of the bearing respectively, and obtain the reading dwx2 of the dial gauge; Move the inner ring of the bearing axially relative to the micrometer by a distance A, adjust the two steel balls of the micrometer with a diameter of dwx to be tangent to only one side of the groove side wall, and obtain the reading of the micrometer dwx2p; Replace the micrometer or the steel ball of the micrometer, adjust the two steel balls with a diameter of dwz to be tangent to the two groove side walls of the inner ring of the bearing respectively, and obtain the reading value dwz2 of the micrometer; where dwx≠dwz; Substitute the above readings into the following two equations for iterative solution to obtain the raceway angle α and raceway skew angle β of the crossed cylindrical roller bearing: (dwz2-dwx2+dwz-dwx)×sinn((dwz-dwX)×cos dwx2p=dwx2+2×A / tan(α / 2+β) Where: α is a positive angle value, β is a positive angle, a negative angle or 0°.
2. The method for measuring the raceway angle of a crossed cylindrical roller bearing ring according to claim 1, characterized in that: When measuring the diameter of the bearing inner ring raceway, select the bearing inner ring radial line perpendicular to the center connection line of the two steel balls as the direction to move the bearing inner ring multiple times, record the reading of the micrometer after each movement, and take the maximum value as the effective reading.
3. The method for measuring the raceway angle of a crossed cylindrical roller bearing ring according to claim 1, characterized in that: When measuring the diameter of the bearing inner ring raceway, rotate the bearing inner ring several times along its circumference, record the reading of the micrometer after each rotation, and take the average value as the effective reading.
4. The method for measuring the raceway angle of a crossed cylindrical roller bearing ring according to claim 1, characterized in that: When obtaining the readings dwx2 and dwz2, adjust the position of the inner ring of the bearing along the axial direction until there is no shaking between the inner ring of the bearing and the two steel balls in the axial direction, and then obtain the reading of the micrometer.
5. The method for measuring the raceway angle of a crossed cylindrical roller bearing ring according to claim 1, characterized in that: Before obtaining the reading of the micrometer, apply a force to keep the inner ring of the bearing stable on one end face of the inner ring of the bearing in a direction perpendicular to the connecting line of the centers of the two steel balls.
6. A method for measuring the raceway angle of a crossed cylindrical roller bearing ring according to claim 5, characterized in that: A limiter is used to apply a force to keep the inner ring of the bearing stable. The limiter is provided with three contact pins that contact the end surface of the inner ring of the bearing.
7. A method for measuring the raceway angle of a crossed cylindrical roller bearing ring according to claim 6, characterized in that: The position-limiting member comprises a fixed seat, a sliding seat slidably arranged on the fixed seat, a contact pin on the sliding seat, and a length measuring instrument arranged on the fixed seat and capable of detecting the position of the sliding seat.
8. The method for measuring the raceway angle of a crossed cylindrical roller bearing ring according to claim 1, characterized in that: The micrometer uses a high-sphericity steel ball as the needle, and the diameters of the two steel balls on the same micrometer are the same.