JP2013108541A - Rolling bearing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rolling bearing device capable of effectively preventing occurrence of creep and fretting between a rolling bearing and a housing mounted with the rolling bearing.SOLUTION: In the rolling bearing device 100 comprised of a housing 30, a housing hole 30a formed in the housing 30, the rolling bearing 10 mounted in the housing hole 30a, and a bearing cover 24 for fixing the rolling bearing 10, between an inner circumferential surface 30b of the housing hole 30 and an outer circumferential surface of the rolling bearing 10, a bellows-shaped elastic body 22 formed with peak parts 22c and trough parts 22d continuously is interposed while being compressed and deformed in the axial direction of the rolling bearing 10.

Description

  The present invention relates to a rolling bearing device.

  Generally, a rolling bearing device is mounted by fitting a rolling bearing into a hole formed in a housing. Normally, when the rolling bearing is mounted in the hole, a so-called gap fitting is formed in which a gap is formed between the rolling bearing and the housing hole. For this reason, in particular, a rolling bearing of a rolling bearing device incorporated in a rotating device such as a motor or a spindle may cause a creep phenomenon in which the rolling bearing relatively rotates in the circumferential direction due to rotation (or load) of the motor or spindle. In addition, when the vibration of the motor or spindle is large, fretting may occur due to relative rotation between the rolling bearing and the housing hole. For this reason, there is a rolling bearing device in which an elastic body is interposed between the rolling bearing and the housing hole to prevent creeping phenomenon and fretting of the rolling bearing (Patent Document 1).

Japanese Utility Model Publication No. 7-6521

  As described above, when an elastic body (O-ring) such as rubber or resin is interposed, the force to stop creep is weak, and it is difficult to stop when the creep force is large. That is, in order to increase the creep prevention force, the interference of an elastic body such as rubber must be increased, but if it is increased, it cannot be inserted into the housing hole when the rolling bearing is assembled. Also, an elastic body such as rubber is damaged at the edge of the housing hole when inserted into the housing hole. Accordingly, an object of the present invention is to provide a rolling bearing, a housing to which the rolling bearing is mounted, and a rolling bearing device capable of preventing the occurrence of creep and fretting.

  In order to solve the above-mentioned problem, the invention described in claim 1 includes a housing, a housing hole formed in the housing, a rolling bearing mounted in the housing hole, and a bearing cover for fixing the rolling bearing. In the rolling bearing device, a bellows-like elastic body in which a crest and a trough are continuously formed between the inner peripheral surface of the housing hole and the outer peripheral surface of the rolling bearing is provided in the axial direction of the rolling bearing. It is characterized by being interposed in a compressed and deformed state.

  According to the present invention, the elastic body is an elastic body having an interference between the outer peripheral surface of the rolling bearing outer ring and the inner peripheral surface of the housing hole when the rolling bearing outer ring is fitted. Since the end surface of the roller bearing is smaller than the clearance between the rolling bearing and the housing hole before contacting the bearing cover, it can be easily incorporated into the clearance between the rolling bearing and the housing hole, and one end surface of the outer ring of the rolling bearing contacts the bearing cover. At the time of contact, the bearing cover provided on the housing or rotating shaft abuts and is fixed to the axial end surface of the rolling bearing to expand the elastic body in the radial direction and generate interference. No rolling process is required, and the housing and rolling bearing can be fixed with relatively rough dimension control of the housing hole, preventing creep and fretting. It can provide.

  The gist of the invention described in claim 2 is that the elastic body is characterized in that a cross section of the peak portion is substantially triangular.

  The gist of the elastic body is that the cross section of the crest and trough is substantially triangular, and the apex of the triangle is an elastic body having an asymmetric structure in the axial direction. For this reason, when a compressive force is applied in the axial direction, the axial surface pressure distribution of the contact portion of the inner periphery of the housing becomes asymmetric even when the axial force is easily deformed and the axial force is no longer applied. Because the frictional resistance in the reciprocating direction in the axial direction is increased, the elastic body is difficult to move in the axial direction opposite to the assembly, and the interference of the elastic body is difficult to change, and the rolling bearing can be fixed. A rolling bearing device capable of preventing fretting can be provided.

  A bearing device capable of preventing the occurrence of creep and fretting between the rolling bearing and the housing to which the rolling bearing is mounted can be provided.

The longitudinal cross-sectional view of the rolling bearing apparatus which concerns on embodiment of this invention. (A) Schematic sectional view showing the state of the elastic body before assembly, (b) Schematic sectional view showing the state of the elastic body after incorporation.

  Hereinafter, each embodiment of the rolling bearing device according to the present invention will be described in detail with reference to the drawings.

  As shown in FIG. 1, the rolling bearing device 100 includes a rolling bearing 10, a housing 30, and a shaft 40. The rolling bearing 10 is fitted in a housing hole 30 a formed in the housing 30, and the shaft 40 is fitted in the inner ring 11 of the rolling bearing 10.

  The rolling bearing 10 includes an inner ring 11, an outer ring 12, a plurality of balls 13 which are rolling elements provided rotatably between the inner ring 11 and the outer ring 12, and the balls 13 at predetermined intervals in the circumferential direction. A cage 14 that is rotatably held, and seals 15 that are respectively fixed to both ends in the axial direction of the outer ring 12 are provided.

  The housing hole 30a has an inner peripheral surface 30b made of a cylindrical surface and a flange 30c extending radially inward from one end of the inner peripheral surface 30b.

  The elastic body 22 is disposed between the opening end of the housing hole 30a and the flange portion 30c with respect to the axial direction of the rolling bearing outer ring 12, and a bearing cover 24 that restricts the movement of the elastic body 22 in the axial direction is provided. . The side surface 22b on the side of the elastic body 22 on the anti-bearing cover side contacts the end surface 30d of the flange portion 30c of the housing, thereby moving in the axial direction simultaneously with the rolling bearing outer ring 12 with respect to the housing 30 in the axial direction of the rolling bearing 10. To regulate.

  The elastic body 22 may be rubber or thermoplastic elastomer as an elastic material. Examples of rubber include acrylic rubber, polyurethane, NBR (acrylonitrile butadiene rubber) CR (chloroprene rubber), synthetic rubber of silicone rubber, and thermoplastic elastomer. And thermoplastic elastomers such as urethane, ester and amide.

  2A is a schematic cross-sectional view showing a state of the elastic body 22 before assembling, and FIG. 2B is a schematic cross-sectional view showing a state of the elastic body 22 after assembling. As shown in FIG. 2A, the elastic body 22 is a cylindrical ring having a bellows portion in which a plurality of peak portions 22c and valley portions 22d are alternately arranged in the axial direction, and the peak portions 22c and the valley portions 22d are The cross section is substantially triangular, and the triangular cross section 22c of the elastic body 22 having an asymmetric structure with the apex of the triangle in the axial direction is formed in an annular shape. The length L of the inclined surface 22e of the triangular cross-sectional shape 22c is longer than the gap m between the inner peripheral surface 30b of the housing 30 and the outer ring 12 of the rolling bearing 10, and the length n of the elastic body rolls with the inner peripheral surface 30b of the housing 30. It is smaller than the clearance m with the outer ring 12 of the bearing 10. Therefore, the elastic body 22 is in a non-compressed state inserted into the housing hole 30a. When assembled, the length n of the elastic body is smaller than the gap m, so that the elastic body 30 can be easily mounted in the gap.

  Next, the trough portion 22 of the elastic body 22 is pressed against the bearing cover 24 and the flange portion 30c of the housing 30, whereby the elastic body 22 is axially compressed and deformed, and at the same time, the inclined surface 22e of the triangular cross section 22c is vertical (the rolling bearing 10). As a result, as shown in FIG. 2 (b), the elastic body 22 is compressed in the axial direction of the rolling bearing 10, and then the elastic body 22 is assembled. Increases in diameter, and an interference is generated in the gap between the inner peripheral surface 30 b of the housing 30 and the outer ring 12 of the rolling bearing 10, and the rolling bearing 10 is tightly fixed to the housing 30.

  At this time, the triangular cross-sectional shape 22c of the elastic body has an asymmetrical structure in which the apexes of the triangle are axially asymmetric. Because the distribution is different, it is easy to move in the assembling direction, but the frictional force increases in the opposite direction, so it is difficult to move back to the original shape before assembling, resulting in a radial interference. Can be difficult to change.

  The elastic body 22 can be selected from any resin or rubber within the scope of the present invention, and can be modified within the scope of the present invention as long as it is a material having other spring properties (elasticity). In this embodiment, the cross section of the elastic body 22 has an asymmetric shape in the axial direction. However, if the shape is easy to move in the axial direction before assembly and difficult to move in the opposite axial direction after assembly, the free-side rolling bearing There is little damage to the function. Furthermore, although the elastic body 22 is formed in an annular shape in the present embodiment, it may have a substantially C-shape obtained by dividing a part of the annular shape, and may be at least half a circle or more. Although not shown and described in particular, it goes without saying that the same mechanism as in the present embodiment can be applied to creep that may occur between the inner ring 11 and the shaft 40.

  The rolling bearing of the present invention is used as a free-side rolling bearing in, for example, a spindle-type rolling bearing device that supports a rotating shaft with two or a plurality of rolling bearings such as a motor, but the application example is not limited. In the present embodiment, a deep groove ball bearing will be described as an example of the rolling bearing of the present invention. However, the present invention is not limited at all, and the present invention can of course be applied to a roller bearing.

  DESCRIPTION OF SYMBOLS 10 ... Rolling bearing, 22 ... Elastic body, 24 ... Bearing cover, 25 ... Mounting bolt, 30 ... Housing, 40 ... Rotating shaft

Claims (2)

In a rolling bearing device comprising a housing, a housing hole formed in the housing, a rolling bearing mounted in the housing hole, and a bearing cover for fixing the rolling bearing, an inner peripheral surface of the housing hole and the rolling bearing A rolling bearing characterized in that a bellows-like elastic body in which peaks and valleys are continuously formed is interposed between the outer peripheral surface of the rolling bearing and compressed in the axial direction of the rolling bearing. apparatus. The rolling bearing device according to claim 1, wherein the elastic body has a substantially triangular cross section.

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