Bearing retainer, rolling ball bearing and motor

[0035] Example 1

[0036] In this embodiment, a bearing cage is provided, such as Figure 1-Figure 5 As shown, the cage 10 has a support portion 11 along its axial side, and the support portion 11 is covered with a sealing body 12 , and the sealing body 12 is used for sealing the inner ring 21 and the inner ring 21 of the bearing 20 . In the gap between the outer rings 22 , the sealing body 12 is provided with a shaft seal installation hole 121 , and the shaft seal installation hole 121 is coaxially disposed with the cage 10 .

[0037] Optionally, the sealing body may be rubber.

[0038] Preferably, an annular spring 50 is embedded in the sealing body 12 , and the annular spring 50 is coaxially arranged with the shaft seal installation hole 121 and is located at the position of the shaft seal installation hole 121 to ensure that the shaft seal installation hole 121 is connected to the shaft seal installation hole 121 . Sealed shaft surfaces fit together.

[0039]Specifically, the sealing body 12 has an annular inner ring sealing portion 122 , an annular outer ring sealing portion 123 and an annular end face sealing portion 124 . The inner ring sealing portion 122 and the outer ring sealing portion 123 are in the The end face sealing portion 124 extends from one side and is located on both sides in the radial direction of the cage 10 , the inner ring sealing portion 122 is used for sealingly embedding the inner ring 21 , and the outer ring sealing portion 123 is used for It is tightly embedded on the outer ring 22 . Preferably, the inner ring sealing portion 122 is used for sealingly embedded in the outer circular surface of the inner ring 21 , and is provided close to the end face of the inner ring 21 , and the outer ring sealing portion 123 is used for sealingly embedding the outer ring 22 The inner circular surface of the outer ring is set close to the end face of the outer ring. The inner ring sealing part 122, the outer ring sealing part 123 and the annular end surface sealing part 124 form a closed annular retaining ring, which can block the external dust and oil from inside the bearing. When this embodiment is applied to the bearing of the motor, external dust and oil can be blocked from entering the inner space of the motor, and the sealing body faces the outside of the bearing of the motor. At the same time, the shaft seal installation hole 121 cooperates with the motor shaft, which can prevent the oil, dust, etc. on the equipment connected to the motor from entering the motor. At the same time, the length of the motor is shortened, which is beneficial to improve the heat dissipation effect of the motor. Preferably, the outer ring sealing portion 123 and/or the inner ring sealing portion 122 is a labyrinth seal structure, so that it can provide axial clearance and seal during assembly to prevent grease leakage.

[0040] Further, the end face sealing portion 124 is disposed protruding from the end face of one side of the bearing, and can be in contact with the front end cover of the motor base to form a radial seal.

[0041] In order to further improve the sealing performance of the sealing body 12, in one implementation of this embodiment, image 3 As shown, the radially extending section 111 extends to one side of the axially extending section 112, and the support portion 11 is annular and has a radially extending section 111 and an axially extending section 112, the axially extending section 112 is formed in On the cage 10, the radially extending section 111 is connected to the axially extending section 112, image 3 The shaft seal installation hole 121 is located in the bearing inner ring 21 , and the diameter of the shaft seal installation hole 121 is smaller than the inner diameter of the bearing inner ring 21 . like Figure 5 As shown, it is another structure of the support portion 11, the radially extending section 111 extends to both sides of the axially extending section 112, Figure 5 The shaft seal mounting hole 121 is located at the outer side of the bearing inner ring 21 in the axial direction. The sealing body 21 is covered on the radially extending section 111 and the axially extending section 112 , which not only makes the sealing body 21 more firmly fixed on the support part 11 , but also provides support for the sealing of the sealing body 21 . , it can also keep the rolling elements of the bearing from moving at a predetermined position. image 3 The structure in which the radially extending section 111 extends to one side of the axially extending section 112, the shaft seal mounting hole 121 is located in the bearing inner ring 21, the structure is more compact, the space of the motor is saved, and the length of the motor can be made more compact. Small, which is conducive to the heat dissipation of the motor.

[0042] Further, the retainer 10 is provided with a plurality of compression springs 30 along the circumferential direction. The axes of the cage are arranged in parallel. After the bearing is installed, due to the existence of the preload, the compression spring 30 will be compressed to generate a preload on the cage, and the axial clearance of the bearing can be adjusted by changing the preload. Specifically, the retainer 10 is provided with a plurality of guide posts 13 extending along its axial direction, and each of the compression springs 30 is sleeved on each of the guide posts 13 . The length of the guide post 13 should be greater than half the length of the compression spring 30 . Preferably, one end of the compression spring 30 abuts on the sealing body 12 through a gasket 40, and the gasket 40 is sleeved on the guide post 13, so that the acting force can be more uniform. Optionally, according to the axial load that the bearing can bear, the pressure range of the compression spring is 10N

[0043] Further, the sealing body 12 is provided with a first bulge a and a second bulge b that respectively surround the retainer 10 on the same side of the inner ring sealing portion 122 ; the first bulge a is It is used to sealingly fit on the outer surface of the inner ring 21 and cover the insertion position of the inner ring sealing portion 122 ; the second protrusion b is used to sealingly fit on the outer ring 22 The inner circular surface covers the insertion position of the outer ring sealing portion 123 . The first protrusion a and the second protrusion b are located on both sides of the holder 10 . Optionally, the inner ring sealing portion 122 is formed by extending from the side of the first protrusion a toward the inner ring 21 . The outer ring sealing portion 123 is formed to extend from the side of the second protrusion b toward the outer ring 22 .

[0044] like figure 1 As shown, it is a structure in which the motor adopts an oil seal to seal at the shaft extension in the prior art, and the front end of the motor supports the sealing structure, which specifically includes a machine base 1, a wave spring retaining ring 4, an oil seal 5, a rolling ball bearing 3 and a motor shaft 2, The motor shaft 2 is rotatably mounted on the machine base 1 through the rolling ball bearing 3 , the motor shaft 2 is provided with a shaft shoulder, the shaft shoulder rests on the end face of the rolling ball bearing 3 , and the wave spring retaining ring 4 is arranged on the end face of the rolling ball bearing 3 , the distance from the shaft shoulder to the rolling ball bearing 3 is L 1 , the thickness of the wave spring retaining ring 4 is L 2 , the distance between the wave spring retaining ring 4 and the end face of the oil seal 5 is L 3 , the distance from the end face of the oil seal 5 to the end face of the base 1 is L 4 , then the distance L=L from the shaft shoulder to the end of the oil seal 1 +L 2 +L 3 +L 4.

[0045] like figure 2 As shown, in this embodiment, when the shaft seal mounting hole 121 is located in the bearing inner ring 21, the distance from the shaft shoulder to the rolling ball bearing 3 is L 1 , the thickness of the sealing part 124 on the upper end face of the sealing body is L 2 , the distance from the sealing surface of the end face sealing part 124 to the end face of the base 1 is L 3 , then the distance L=L from the shaft shoulder to the end of the oil seal 1 +L 2 +L 3 , By comparison, it can be seen that the application of the cage in this embodiment to the motor significantly shortens the length of the motor in the axial direction, and the sealing body is covered on the cage to avoid the problem of easy falling off of the oil seal during installation , while improving the assembly efficiency.

[0046] The above is an example of the bearing cage in this embodiment and the motor bearing, but this embodiment is not limited to the application of the bearing cage to the motor bearing, and can also be applied to other bearings, such as deep groove ball bearings, angular Contact ball bearings, etc.

[0047] Example 2

[0048] The present invention provides a rolling ball bearing, including the bearing cage described in Embodiment 1.

[0049] Specifically, as image 3 and Figure 5 As shown, the rolling ball bearing further includes: an inner ring 21; a ball rolling body 23, the cage 10 is provided with a plurality of pockets c along its circumferential direction, and each pocket c is provided with a ball rolling body 23 ; Outer ring 22, coaxially sleeved on said inner ring 21, an annular gap is formed between said outer ring 22 and said inner ring 21, said annular gap is provided with a plurality of uniformly arranged along its circumferential direction The ball rolling body 23, the cage 10 is arranged in the annular gap.

[0050] Further, the outer surface of the inner ring 21 is provided with a first annular sealing groove 211 coaxial with it, and the inner ring sealing portion 122 is sealingly embedded in the first annular sealing groove 211; The outer circular surface is provided with a second annular sealing groove 221 coaxial therewith, and the outer ring sealing portion 123 is sealingly embedded in the second annular sealing groove 221 .

[0051] Further, the first annular sealing groove 211 and the second annular sealing groove 221 respectively have three sealing surfaces, and the inner ring sealing portion 122 is in contact with the three sealing surfaces of the first annular sealing groove 211 . The outer ring sealing portion 123 is in contact with the three sealing surfaces of the second annular sealing groove 221 .

[0052] The first protrusion a blocks the first annular sealing groove 211 , and the second protrusion b blocks the second annular sealing groove 221 .

[0053] Example 3

[0054] The present invention provides a motor, including the rolling ball bearing described in Embodiment 2.

[0055] like figure 2 As shown, the motor further includes: a machine base 1, the front end of which is provided with a bearing shoulder c; a motor shaft 2, which is rotatably mounted on the machine base 1 through the rolling ball bearing 3, and all the The end face sealing portion 124 on the bearing cage is in sealing fit with the shoulder c, and the shaft sealing mounting hole 121 is in sealing fit with the motor shaft 2 .

[0056] by the formula:

[0057]

[0058]

[0059] Among them, RA—represents the thermal resistance per unit area, δ—represents the thickness of the thermally conductive material, λ—represents the thermal conductivity (thermal conductivity), φ—represents the heat flow through a given area A per unit time, θ—represents the two end temperature difference.

[0060] From the above formulas (1) and (2), it can be seen that when the thickness (length) of the front end of the casing decreases, the heat flow of a given area per unit time increases, which can transfer the heat generated by the winding to the front flange more quickly, and then At the same time, the thermal resistance of the front end of the motor is reduced, and the heat transfer path is closer to the front end, which can effectively reduce the temperature rise of the encoder. This structure can reduce the temperature rise of the motor, improve the performance, and effectively shorten the length of the motor.