bearings

Abstract

The present invention provides a bearing that not only provides pre-pressure to the bearing but also reduces the number of assembly parts and improves ease of assembly. [Solution] The bearing 100 according to the present invention is characterized by comprising: an outer ring 104; an inner ring 108; balls 110 that roll between the outer ring and the inner ring; a stepped portion 114 provided at one end 120 of the outer circumferential surface 118 of the outer ring and having a smaller diameter than the outer circumferential surface; and an annular elastic member 116 having elasticity in the axial direction, which is fitted to the stepped portion so as to protrude in the axial direction from the side surface 122 of the outer ring on the side where the stepped portion is provided.

Description

Technical Field

[0001] The present invention relates to a bearing having rolling elements that roll between an inner ring and an outer ring.

Background Art

[0002] In bearings, for example, it is required to suppress rattling accompanying the rotation of a shaft and to suppress vibration and noise. For example, Patent Document 1 describes an electric linear actuator provided with a support bearing. In this electric linear actuator, a disc spring is elastically attached between the outer ring of the support bearing and the housing, thereby applying a pressure to the support bearing to suppress vibration and noise.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the electric linear actuator of Patent Document 1, although a pressure can be applied to the support bearing by the disc spring, it is necessary to assemble the disc spring elastically between the outer ring of the support bearing and the housing, which is troublesome during assembly. Further, since the support bearing and the disc spring, which are separate parts with respect to the housing, are assembled, the number of parts during assembly also increases.

[0005] In view of such problems, an object of the present invention is to provide a bearing that can not only apply a pressure to the bearing but also reduce the number of assembled parts and improve the assemblability.

Means for Solving the Problems

[0006] To solve the above problems, a typical bearing configuration according to the present invention is characterized by comprising: an outer ring; an inner ring; rolling elements that roll between the outer ring and the inner ring; a stepped portion provided at one end of the outer circumferential surface of the outer ring and having a smaller diameter than the outer circumferential surface; and an annular elastic member having elasticity in the axial direction, which is fitted into the stepped portion so as to protrude in the axial direction from the side surface of the outer ring on the side where the stepped portion is provided.

[0007] Preferably, the stepped portion described above has a fitting surface into which the elastic member fits, and a taper that extends from the fitting surface to the side surface of the outer ring, with the diameter decreasing as it approaches the side surface of the outer ring. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a bearing that not only provides pre-pressure to the bearing but also reduces the number of assembly parts and improves ease of assembly. [Brief explanation of the drawing]

[0009] [Figure 1] This figure shows a bearing in an embodiment of the present invention. [Figure 2] This figure schematically shows the main parts of the bearing in Figure 1. [Figure 3] This is a diagram showing the elastic member in Figure 1. [Modes for carrying out the invention]

[0010] Preferred embodiments of the present invention will be described in detail below with reference to the attached drawings. The dimensions, materials, and other specific numerical values ​​shown in these embodiments are merely examples to facilitate understanding of the invention and do not limit the present invention unless otherwise specified. In this specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals to avoid redundant explanations, and elements not directly related to the present invention are omitted from the illustrations.

[0011] Figure 1 shows a bearing 100 in an embodiment of the present invention. In the figure, a part of the bearing 100 is cut out to show its internal structure. Figure 2 is a schematic diagram showing the main parts of the bearing 100 in Figure 1.

[0012] The bearing 100 is a ball bearing comprising an outer ring 104 having a raceway surface 102 on its inner circumference, an inner ring 108 having a raceway surface 106 on its outer circumference, a row of balls 110 as rolling elements, and a cage 112.

[0013] The ball 110 rolls between the raceway surface 102 of the outer ring 104 and the raceway surface 106 of the inner ring 108. The retainer 112 is provided between the outer ring 104 and the inner ring 108, as shown in Figure 2, and plays the role of holding the ball 110, maintaining the spacing between the balls 110, and preventing the balls 110 from rubbing against each other.

[0014] Furthermore, the bearing 100 includes a stepped portion 114 provided on the outer ring 104 and an elastic member 116 that fits into the stepped portion 114. The stepped portion 114 is provided circumferentially on one end 120 of the outer circumferential surface 118 of the outer ring 104 and has a smaller diameter than the outer circumferential surface 118 of the outer ring 104. The stepped portion 114 has a fitting surface 114a and a taper 114b.

[0015] The fitting surface 114a of the stepped portion 114 is a straight cylindrical shape and is the surface into which the elastic member 116 fits. The taper 114b extends from the fitting surface 114a to the side surface 122 of the outer ring 104 (i.e., the side surface 122 of the outer ring 104, 124, on which the stepped portion 114 is provided), and its diameter decreases as it approaches the side surface 122 of the outer ring 104.

[0016] The elastic member 116 is an annular member that has elasticity in the axial direction. When fitted onto the fitting surface 114a of the stepped portion 114, the elastic member 116 protrudes axially from the side surface 122 of the outer ring 104, as shown in Figures 1 and 2(a).

[0017] FIG. 3 is a view showing the elastic member 116 of FIG. 1. The elastic member 116 is, for example, a wave spring (also called a wave washer or a wave ring), and is formed such that the axial convex portions 116a and the concave portions 116b are alternately repeated in the circumferential direction, so as to have elasticity in the axial direction and be able to fit into the stepped portion 114.

[0018] Thus, as shown in FIGS. 1 and 2(a), the elastic member 116 can be incorporated into the bearing 100 to form an integral structure. And the bearing 100 having the integral structure is in a state where the elastic member 116 fitted to the stepped portion 114 protrudes axially from the side surface 122 of the outer ring 104 (a protruding state).

[0019] Therefore, as shown in FIG. 2(b), when the bearing 100 is assembled between the housing 126 on the outer ring 104 side and the shaft (shaft 128) on the inner ring 108 side, the elastic member 116 is pressed against the housing 126 and compressed, and the outer ring 104 receives a reaction force.

[0020] As a result, a force acting in the direction of axially displacing the outer ring 104 and the inner ring 108 is continuously applied to the bearing 100, and a preload Fa is applied by this force. Further, since the bearing 100 absorbs the energy of vibration by the compression of the elastic member 116, it can have a vibration damping function.

[0021] Furthermore, the bearing 100 can suppress the occurrence of creep in which the outer ring 104 rotates and shifts in the circumferential direction by generating a frictional force between the stepped portion 114 of the outer ring 104 and the housing 126 by the applied pressure Fa. And since the elastic member 116 is pre-fitted to the stepped portion 114 of the outer ring 104 in the bearing 100, the number of parts at the time of assembly can be reduced, and the assemblability can be improved.

[0022] Also, in the bearing 100, a taper 114b is formed continuously from the fitting surface 114a of the stepped portion 114 to the side surface 122 of the outer ring 104. For this reason, it becomes easier to press-fit the elastic member 116 from the side surface 122 side of the outer ring 104 to the fitting surface 114a of the stepped portion 114.

[0023] Furthermore, since the taper 114b has a smaller diameter than the fitting surface 114a, the elastic member 116 does not rub against the taper 114b when it expands and contracts. Therefore, the elastic member 116 can freely expand and contract, and the pressing force Fa is surely applied when the bearing 100 is assembled.

[0024] In the above bearing 100, a wave spring is exemplified as the elastic member 116, but it is not limited thereto. For example, an annular elastic member having elasticity in the axial direction, such as a helical spring, may be used as long as it can be fitted to the stepped portion 114 of the outer ring 104.

[0025] As described above, the preferred embodiments of the present invention have been described with reference to the accompanying drawings. Needless to say, the present invention is not limited to such examples. It is obvious that those skilled in the art can conceive of various modification examples or correction examples within the scope described in the claims, and it is naturally understood that they also belong to the technical scope of the present invention.

Explanation of Reference Numerals

[0026] 100... bearing, 102... raceway surface of outer ring, 104... outer ring, 106... raceway surface of inner ring, 108... inner ring, 110... ball, 112... cage, 114... stepped portion, 114a... fitting surface, 114b... taper, 116... elastic member, 116a... convex portion of elastic member, 116b... concave portion of elastic member, 118... outer peripheral surface of outer ring, 120... one end of outer peripheral surface of outer ring, 122, 124... side surfaces of outer ring, 126... housing, 128... shaft

Claims

1. Outer ring and, Insider, A rolling element that rolls between the outer ring and the inner ring, A stepped portion is provided at one end of the outer circumferential surface of the outer ring and has a smaller diameter than the outer circumferential surface, A bearing characterized by comprising an annular elastic member having elasticity in the axial direction, the elastic member being fitted to the stepped portion such that it protrudes in the axial direction from the side surface of the outer ring on the side where the stepped portion is provided.

2. The aforementioned stepped portion is The fitting surface into which the elastic member fits, The bearing according to claim 1, characterized in that it has a taper that extends from the fitting surface to the side surface of the outer ring, and whose diameter decreases as it approaches the side surface of the outer ring.

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