Retainer for rolling contact fatigue testing machine
By designing a rotatably installed cage for rolling contact fatigue testing machines, the problem of difficulty in replacement in traditional ball embedded cages is solved, and the ball is replaced easily and the testing cost is reduced.
Patent Information
- Application Number
- CN202420061532.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-10
- Publication Date
- 2025-01-10
- Estimated Expiration
- 2034-01-10
AI Technical Summary
The balls in traditional cages are embedded on the cage body, making it difficult to replace the balls and increasing the cost of testing.
A cage for a rolling contact fatigue testing machine is designed, which includes an annular cage body and a plurality of balls. The balls are rotatably installed on the cage body through the mounting holes. The mounting holes are composed of a cylindrical and a ball table-like cavity, allowing Easy to remove and replace the ball.
It realizes convenient replacement of balls, reduces test costs, and avoids the need to replace the entire cage.
Smart Images
Figure CN222334283U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of retaining frames, in particular to a retaining frame for a rolling contact fatigue testing machine. Background Art
[0002] Rolling contact fatigue is the most common failure mode in bearings. Especially under complex working conditions such as high speed and heavy load, rolling contact fatigue can cause premature failure of bearings, seriously affecting the reliability and service life of actual parts during use. Therefore, it is necessary to conduct rolling contact fatigue testing on the bearing material.
[0003] The necessary accessories required for the rolling contact fatigue test of bearings include cages, shaft rings and annular specimens. The cage includes a cage body and multiple balls. The cage body is annular, and multiple mounting holes that penetrate the cage body are evenly opened on the upper surface of the cage body. The cavity formed in the mounting hole is cylindrical, and the diameter of the ball is slightly smaller than the diameter of the mounting hole. The ball is placed in the mounting hole of the cage body, and then the cage body is squeezed to make the ball embedded in the mounting hole. The annular specimen is in the shape of an annular plate, and the lower surface of the shaft ring is provided with an annular groove.
[0004] When conducting a contact fatigue test, the ring specimen needs to be loaded at the bottom of the test chamber, and then the cage is placed on the ring specimen. Then, the lubricating oil is poured into the test chamber until the cage is just immersed, and then the shaft ring is placed on the cage, and the ball is located in the annular groove of the shaft ring. Then apply a suitable load to the shaft ring, start the test equipment, and set a suitable speed. The contact fatigue tester will drive the shaft ring to rotate, and the rotation of the shaft ring will drive the ball in the annular groove to rotate on the ring specimen. After a certain number of cycles of cyclic contact stress, small pieces may peel off in some areas of the working surface of the ring specimen, the ball, or the shaft ring, forming pits or pits. The cause is the noise, wear, vibration, and temperature rise generated during the rotation process. As the shaft ring keeps rotating, the peeling continues to deepen, and the vibration generated will continue to increase. When the vibration value reaches a certain threshold set in advance, the test stops. After the test is stopped, open the specimen chamber and observe the surface of the ring specimen, ball or shaft ring. If the failure originates from the surface of the ring specimen, the test is over. If the failure originates from the surface of a ball or the annular groove of the shaft ring, the failed retainer or shaft ring must be replaced and the test is continued until the surface of the ring specimen fails. At this time, the test is over.
[0005] Since the balls in the above cage are embedded in the cage body, there is hard contact between the balls and the cage body. When the failure originates from the balls, since the balls are difficult to remove and replace, the entire cage needs to be replaced, resulting in an increase in the test cost. Utility Model Content
[0006] (I) The problem to be solved by the utility model is that the balls in the conventional cage are embedded in the cage body, and there is hard contact between the balls and the cage body. When the failure originates from the balls, since the balls are difficult to remove and replace, the entire cage needs to be replaced, resulting in an increase in the test cost.
[0007] (II) Technical solution
[0008] A cage for a rolling contact fatigue testing machine comprises a cage body and a plurality of balls, wherein the cage body is in a ring shape;
[0009] A plurality of mounting holes penetrating the retainer body are provided on the retainer body along the axial direction thereof, a ball is placed in each mounting hole, and the mounting holes are evenly arranged around the axis of the retainer body;
[0010] The ball is rotatably mounted in the mounting hole so that the ball can be taken out from the mounting hole.
[0011] According to an embodiment of the utility model, the mounting hole comprises a cavity 1 and a cavity 2 which are connected, and the cavity 1 is lower than the cavity 2;
[0012] The first cavity is a cylindrical cavity, the second cavity is a spherical cavity, and the diameter of the first cavity is greater than the maximum diameter of the second cavity.
[0013] According to an embodiment of the present invention, an arc-shaped transition is formed at the connection between the cavity 1 and the cavity 2.
[0014] According to an embodiment of the present invention, the diameter of the cavity 1 is greater than the diameter of the ball.
[0015] According to an embodiment of the present invention, the height of the retainer body is smaller than the diameter of the ball.
[0016] According to an embodiment of the present invention, the axes of the plurality of mounting holes all pass through the same concentric circle of the retaining frame body.
[0017] According to an embodiment of the utility model, the number of the mounting holes is 6-12, and the number of the balls is 6-12.
[0018] Beneficial effects of the utility model:
[0019] The utility model provides a retaining frame for a rolling contact fatigue testing machine, comprising a retaining frame body and a plurality of balls, wherein the retaining frame body is in a circular ring shape; a plurality of mounting holes penetrating the retaining frame body are opened on the retaining frame body along its axial direction, a ball is placed in each mounting hole, and the mounting holes are evenly arranged around the axis of the retaining frame body; the balls are rotatably mounted in the mounting holes so that the balls can be taken out of the mounting holes.
[0020] When conducting the touch fatigue test, first load the ring sample piece at the bottom of the test chamber, then take out multiple balls and place them symmetrically and evenly on the ring sample piece, then the cage body buckles multiple balls on the ring sample piece, and the balls enter the mounting holes on the cage body. Then pour lubricating oil into the test chamber until the cage body and the balls are just immersed, and then place a shaft ring with an annular groove on the top of the cage, the shaft ring is placed on the balls, and the balls enter the annular groove of the shaft ring. Before the test, apply a suitable load to the shaft ring, start the test equipment, set a suitable speed, and the contact fatigue testing machine will drive the shaft ring to rotate. The rotation of the shaft ring will drive the ball in the annular groove to rotate on the annular specimen. After a certain number of cycles of cyclic contact stress, small pieces may peel off in some areas of the working surface of the annular specimen, the ball, or the shaft ring, forming pits or pits. The cause is the noise, wear, vibration, and temperature rise generated during the rotation process. As the shaft ring continues to rotate, the peeling continues to deepen, and the vibration generated will continue to increase. When the vibration value reaches a certain threshold set in advance, the test stops. After the test stops, open the sample chamber and observe the surface of the ring sample, ball or shaft ring. If the failure originates from the surface of the ring sample, the test is over; if the failure originates from the surface of a certain ball, the retainer body can be directly removed, and then the failed ball is replaced, and then the retainer body is snapped onto the ball; if the failure originates from the shaft ring, replace the failed shaft ring; finally, continue the test until the surface of the ring sample fails, and the test is over.
[0021] Since the ball is no longer embedded in the mounting hole in the cage body, the ball is only locked by the mounting hole. Therefore, when the ball fails and needs to be replaced, the cage body can be removed and the failed ball can be removed from the specimen, and then a new ball can be replaced, and finally the cage body can be re-covered on the ball. In this way, when the ball fails, there is no need to replace the cage, only the failed ball can be replaced, thus saving the test cost. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0023] Figure 1 A top view of a retainer provided in an embodiment of the utility model;
[0024] Figure 2 The embodiment of the utility model provides Figure 1 Sectional view of AA in the middle;
[0025] Figure 3 A structural diagram of a cage provided by an embodiment of the utility model after removing the balls;
[0026] Figure 4 This is a cross-sectional view of the retaining frame provided by an embodiment of the utility model after the balls are removed.
[0027] Icons: 1. Cage body; 2. Ball; 101. Mounting hole; 102. Cavity 1; 103. Cavity 2. DETAILED DESCRIPTION
[0028] The technical solution of the utility model will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.
[0029] like Figure 1-Figure 4 As shown, an embodiment of the utility model provides a cage for a rolling contact fatigue testing machine, comprising a cage body 1 and a plurality of balls 2, wherein the cage body 1 is in a circular ring shape;
[0030] A plurality of mounting holes 101 penetrating the retainer body 1 are provided on the retainer body 1 along its axial direction. A ball 2 is placed in each mounting hole 101 , and the mounting holes 101 are evenly arranged around the axis of the retainer body 1 ; the ball 2 is rotatably installed in the mounting hole 101 so that the ball 2 can be taken out of the mounting hole 101 .
[0031] In this embodiment, when performing the contact fatigue test, the annular specimen is first loaded at the bottom of the test chamber, and then a plurality of balls 2 are taken out and placed symmetrically and evenly on the annular specimen, and then the retainer body 1 buckles the plurality of balls 2 on the annular specimen, and the balls 2 enter the mounting holes 101 on the retainer body 1. Then, lubricating oil is poured into the test chamber until the retainer body 1 and the balls 2 are just immersed, and then a shaft ring with an annular groove is placed above the retainer, the shaft ring is placed on the balls 2, and the balls 2 enter the annular groove of the shaft ring. Before the test, apply a suitable load to the shaft ring, start the test equipment, set a suitable speed, and the contact fatigue testing machine will drive the shaft ring to rotate. The rotation of the shaft ring will drive the ball 2 in the annular groove to rotate on the annular specimen. After a certain number of cycles of cyclic contact stress, small pieces may peel off in local areas of the working surface of the annular specimen, the ball 2, or the shaft ring, forming pits or pits. The cause is the noise, wear, vibration, temperature rise and other factors generated during the rotation process. As the shaft ring continues to rotate, the peeling continues to deepen, and the vibration generated will continue to increase. When the vibration value reaches a certain threshold set in advance, the test stops.
[0032] After the test is stopped, open the sample chamber and observe the surface of the ring sample, ball 2 or shaft ring. If the failure originates from the surface of the ring sample, the test is over; if the failure originates from the surface of a certain ball, the retainer body 1 can be directly removed, and then the failed ball 2 can be replaced, and then the retainer body 1 can be snapped onto the ball 2; if the failure originates from the shaft ring, replace the failed shaft ring; finally, continue the test until the surface of the ring sample fails, and the test is over.
[0033] In this embodiment, since the ball 2 is no longer embedded in the mounting hole 101 in the cage body 1, the ball 2 is only locked by the mounting hole 101. Therefore, when the ball 2 fails and needs to be replaced, the cage body 1 can be removed and the failed ball 2 can be removed from the test piece, and then a new ball 2 can be replaced, and finally the cage body 1 can be re-covered on the ball 2. In this way, when the ball 2 fails, there is no need to replace the cage, and only the failed ball 2 needs to be replaced, thereby saving the test cost.
[0034] As a preferred embodiment, Figure 4 As shown, the mounting hole 101 includes a connected cavity 102 and a cavity 2 103, and the cavity 2 103 and the cavity 1 102 are sequentially arranged from the upper surface to the lower surface of the retainer body 1. The cavity 102 is a cylindrical cavity, and the cavity 2 103 is a spherical cavity. The diameter of the cavity 102 is greater than the maximum diameter of the cavity 2 103, that is, the diameter of the cavity 102 is greater than the diameter of the lower surface of the spherical cavity.
[0035] Look again Figure 2As shown, when the retainer body 1 is buckled on the ball 2, the top of the ball 2 protrudes from the upper surface of the retainer body 1, the bottom of the ball 2 is lower than the lower surface of the retainer body 1, the outer surface of the ball 2 fits against the inner wall of the cavity 2 103, and the outer surface of the ball 2 does not contact the inner wall of the cavity 1 102.
[0036] In this way, the ball 2 can rotate relative to the mounting hole 101 , that is, the ball 2 is not embedded in the mounting hole 101 . When the ball 2 fails, the retainer body 1 can be removed at any time and replaced with a new ball 2 .
[0037] As a preferred embodiment, Figure 4 As shown, an arc transition 104 is formed at the connection between the inner top wall of cavity one 102 and the inner wall of cavity two 103 to prevent the connection between the inner top wall of cavity one 102 and the inner wall of cavity two 103 from scratching the ball 2.
[0038] Optional, such as Figure 3 As shown, there are six mounting holes 101 on the retainer body 1, and the six mounting holes 101 are evenly arranged around the axis of the retainer body 1, and the distance between every two adjacent mounting holes 101 is the same. Figure 1 As shown, six balls 2 are also provided, and the six balls 2 are respectively installed in six installation holes 101 .
[0039] It should be noted that there is no specific limitation on the number of mounting holes 101 and balls 2 , and they can be set to 8, 10 or 12, for example.
[0040] Optionally, the outer diameter of the holder body 1 is 52±0.1 mm, and the inner diameter is 25.5±0.1 mm. The diameter of the cavity 102 is 9.8±0.05 mm, the minimum diameter of the cavity 2 103 (i.e., the upper plane circle of the spherical table-shaped cavity) is 8.8±0.05 mm, the maximum diameter of the cavity 2 103 (i.e., the lower plane circle of the spherical table-shaped cavity) is 9.2±0.05 mm, and the height of the cavity 2 103 is 1.8 mm±0.05 mm.
[0041] Optionally, the retainer body 1 is made of pure copper.
[0042] In the description of the present invention, it should be noted that the terms "upper" and "lower" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.
[0043] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the insides of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, in the description of the present invention, unless otherwise specified, "plurality" means two or more.
[0044] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.
Claims
1. A cage for a rolling contact fatigue testing machine, characterized in that: It comprises a retainer body (1) and a plurality of balls (2), wherein the retainer body (1) is in a circular ring shape; A plurality of mounting holes (101) penetrating the retainer body (1) are provided on the retainer body (1) along the axial direction thereof, one of the balls (2) being placed in each of the mounting holes (101), and the mounting holes (101) are evenly arranged around the axial line of the retainer body (1); The ball (2) is rotatably mounted in the mounting hole (101) so that the ball (2) can be taken out from the mounting hole (101).
2. A cage for a rolling contact fatigue testing machine according to claim 1, characterized in that: The mounting hole (101) comprises a cavity one (102) and a cavity two (103) which are connected to each other, and the cavity one (102) is lower than the cavity two (103); The cavity one (102) is a cylindrical cavity, the cavity two (103) is a spherical cavity, and the diameter of the cavity one (102) is greater than the maximum diameter of the cavity two (103).
3. A cage for a rolling contact fatigue testing machine according to claim 2, characterized in that: The connection between the cavity one (102) and the cavity two (103) forms an arc-shaped transition (104).
4. A cage for a rolling contact fatigue testing machine according to claim 2, characterized in that: The diameter of the cavity 1 (102) is greater than the diameter of the ball (2).
5. The cage for a rolling contact fatigue testing machine according to claim 1, characterized in that: The height of the retainer body (1) is smaller than the diameter of the ball (2).
6. The cage for a rolling contact fatigue testing machine according to claim 1, characterized in that: The axes of the plurality of mounting holes (101) all pass through the same concentric circle of the retaining frame body (1).
7. The cage for a rolling contact fatigue testing machine according to claim 1, characterized in that: The number of the mounting holes (101) is 6 to 12, and the number of the rolling balls (2) is 6 to 12.