JPS643853Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] This invention is a ball bearing sealed with a shield plate, used in relatively small machines such as office machines, audio equipment, and video equipment. This invention relates to an improved structure of sealed rolling bearings such as roller bearings.

[Conventional technology]

Rolling bearings have annular sealing plates, or shield plates, drilled on the inner diameter surface of both ends of the outer ring of the bearing to prevent the lubricating grease filled inside from leaking outward and to prevent dust from entering from the outside. It is generally done to fit into a circumferential groove.

Figure 1 shows a conventional example of this type of sealed rolling bearing, in which 1 is an outer ring, 2 is an inner ring, 3 is a rolling element disposed between the outer ring 1 and the inner ring 2, and 4 is a rolling element 3. The retainer 5 is a shield plate. The outer ring 1 is provided with a circumferential groove 6 having a substantially U-shaped cross section on its inner diameter surface at both ends. Further, the shield plate 5 is press-formed from a thin metal plate, and its outer peripheral edge is curved and deformed to provide a press-fit portion 7 having a bowl-shaped cross section. Then, the peripheral press-fit portion 7 of the shield plate 5 is directly crimped into the circumferential groove 6 of the outer ring 1, and the press-fit portion 7 is elastically and tightly fitted into the circumferential groove 6 to hold the shield plate 5 in the outer ring 1, and The bearing is sealed by a minute labyrinth gap H formed between the inner circumferential edge of the shield plate 5 and the outer diameter surface of the inner ring 2, thereby forming a sealed rolling bearing.

[The problem that the idea aims to solve]

In the sealed rolling bearing, the press-fitted portion 7 on the outer periphery of the shield plate 5 is elastically and tightly fitted into the circumferential groove 6 bored into the inner diameter surface of the outer ring 1, so that the bending deformation stress is applied to the bottom surface of the circumferential groove 6. In addition, it acts as a fitting retention reaction force in the radial direction toward the outer diameter surface, causing distortion in the outer diameter portion of the outer ring 1, which has a large effect on deformation and dimensional changes of the outer ring 1. In addition, there are many variations in the crimping force, and if the crimping force is too large, the deformation will become large, and conversely, if the crimping force is small, the peripheral press-fit portion 7 will not fully fit into the circumferential groove 6, and the shield There are drawbacks such as the plate 5 idling or coming off, and it is difficult to suppress the deformation and dimensional changes of the outer ring 1 to a small level and to secure the shield plate 5 by crimping to prevent it from idling or coming off. As described above, the structure of conventional sealed rolling bearings is particularly limited in that the outer ring 1 on the side to which the shield plate 5 is fixed is thin, and due to the size, small-diameter bearings, miniature bearings, etc. There are still problems to be solved in application.

Therefore, the purpose of this invention is to create a structure that suppresses deformation and dimensional changes of the outer ring, and also prevents the shield plate from idling or coming off, and is particularly suitable for bearings with thin raceway rings such as small-diameter bearings and miniature bearings. An object of the present invention is to provide an applicable sealed rolling bearing.

[Means to solve the problem]

This invention provides a sealed rolling bearing sealed by a shield plate, in which an annular protrusion with a triangular cross section is provided on the inner diameter surface of the end face of the outer ring, and the entire shield plate is made of a synthetic resin material. An annular lip with an L-shaped cross section is provided protruding inside the outer periphery, and the annular lip and the outer periphery extend parallel to each other while being spaced apart from each other in the axial direction, on both slopes of the triangular annular protrusion. The shield plate is attached to the outer ring by elastic clamping.

[Effect]

According to this invention, an annular protrusion with a triangular cross section formed on the inner diameter surface of the outer ring is elastically held in the axial direction by parallel lips spaced apart in the axial direction, that is, the outer peripheral edge of the shield plate and the annular lip. This allows the shield plate to be held or fixed. Therefore, undesirable radial force is not applied to the outer ring unlike in the conventional case where the outer ring is crimped into the circumferential groove of the outer ring.

In addition, the entire shield plate is made of synthetic resin, and the inner lip of the pair of lips, that is, the annular lip, extends from the outer peripheral edge of the shield plate.
Because the cross section of the letter is protruding, the waist is relatively weak. Therefore, when assembling the shield plate into the bearing, it is only necessary to push the shield plate in the axial direction so that the annular lip elastically deforms and overcomes the annular protrusion on the outer ring. There is no force acting at all.

Furthermore, the holding force of the shield plate is determined exclusively by the dimensional relationship between the annular protrusion of the outer ring and the pair of lips of the shield plate, and the elasticity of the lips, and since these can be set in advance, they can be adjusted individually. There is much less variation compared to the conventional tightening method.

〔Example〕

FIG. 2 shows an embodiment of the sealed rolling bearing according to this invention, in which 11 is an outer ring, 12 is an inner ring,
13 is a rolling element disposed between the outer ring 11 and the inner ring 12, 14 is a retainer for the rolling element 13, and 15 is a shield plate.

The outer ring 11 is provided with a shield plate mounting portion 18 including an annular groove 16 having a triangular cross section and an annular protrusion 17 on the inner diameter surface at both ends.

The shield plate 15 is formed from a synthetic resin material by compression molding, injection molding, etc., and has an annular lip 20 with an L-shaped cross section on its outer peripheral edge 15a, and a fitting groove 19 with a U-shaped cross section. is forming.
In other words, the outer peripheral edge 15a and the annular lip 20
constitute a pair of parallel annular lips spaced apart in the axial direction with the fitting groove 19 in between. It should be noted that while the outer peripheral edge portion 19 extends in approximately the same plane as the inner circular disk portion of the shield plate 15, the annular lip 20 has a shape that extends from the middle of the disk portion. As a result, the waist is weakened so that it can easily be elastically deformed during assembly.

The shield plate 15 formed in this way is first exposed to the end surface of the outer ring 11 with the annular lip 20 as shown in FIG. As shown in FIG. 5, the annular protrusion 17 is fitted into the fitting groove 19 by utilizing the elastic deformation of the annular lip 20, and as shown in FIG. A pair of separated lips, that is, the annular lip 20 and the outer peripheral edge 15a, are applied to both slopes of the triangular annular protrusion 17, and the annular protrusion 17 is elastically clamped in the axial direction and assembled to the outer ring 11. The bearing is sealed by a labyrinth gap H formed between the inner circumferential edge and the outer diameter surface of the inner ring 12 to form a sealed bearing.

FIG. 7 shows another embodiment of this invention, in which the inner peripheral edge of the shield plate 15 is extended to form an edge-shaped seal portion 22, and this seal portion 22 is attached to the inner ring 12. It is made to contact the outer diameter surface to prevent lubricating grease from leaking and to enhance the dustproof effect.

[Effect of idea]

The sealed rolling bearing of this invention has an annular protrusion with a triangular cross section on the inner diameter surface of the outer ring, and this protrusion is elastically clamped in the axial direction by bifurcated lips to attach the shield plate to the outer ring. Since they are assembled, the holding reaction force of the shield plate does not act on the outer diameter side of the outer ring as in the conventional case, and deformation and dimensional changes of the outer ring can be prevented. This effect is particularly noticeable in small-diameter bearings and miniature bearings with thin bearing rings.

In addition, since the shield plate has a bifurcated lip that elastically clamps the protrusion in the axial direction, a secure fixing force can be obtained, and there is no need to worry about the shield plate idling or falling off in the axial direction while the bearing is in use. is resolved. Moreover, the holding force of the shield plate is determined exclusively by the dimensional relationship between the annular protrusion and the lip that holds it, and the elasticity of the lip, and since these can all be set in advance, there is no variation. Provides stable holding power.

Furthermore, as mentioned above, when assembling the shield plate, it is only necessary to push the shield plate from the end face of the outer ring until the relatively weak annular lip overcomes the annular protrusion, making assembly very easy. Not only is it easy to assemble, but there is no need to worry about applying extra force to the outer ring, so no special management is required during assembly. Therefore, together with the reduced variation in the holding force of the shield plate, the structure is suitable for mass production and can significantly reduce assembly-related costs.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a main part showing a conventional sealed rolling bearing, Fig. 2 is a cross-sectional view of a main part showing an embodiment of a sealed rolling bearing according to this invention, and Figs. 3 to 6 are a shield plate. FIG. 7 is a cross-sectional view of a main part showing another embodiment. 11... Outer ring, 12... Inner ring, 13... Rolling element, 14
... Cage, 15... Shield plate, 15a... Outer periphery, 17... Annular protrusion, 18... Shield plate attachment part,
19... Fitting groove, 20... Annular lip, 21... Holding jig, 23... Seal portion.

Claims (1)

[Scope of utility model registration request] In a sealed rolling bearing sealed by a shield plate, an annular protrusion with a triangular cross section is provided on the inner diameter surface of the end face of the outer ring, and the entire shield plate is made of a synthetic resin material, and the outer peripheral edge thereof is An annular lip with an L-shaped cross section is provided protruding inside the triangular protrusion, and the annular lip and the outer peripheral edge extend parallel to each other while being spaced apart from each other in the axial direction, and the annular lip is elastically held between both slopes of the triangular annular protrusion. A sealed rolling bearing characterized in that a shield plate is attached to the outer ring by means of a method.