JP2016145595A - Holder for ball bearing, and ball bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a holder excellent in reinforcement and stability of holding force of a ball in a ball bearing, and a bearing ball using the holder.SOLUTION: A holder for a ball bearing has an outer diameter surface and an inner diameter surface, and in the holder, pockets for holding a ball are arrayed in a ring manner. The pocket has a cylindrical part formed on the inner diameter surface side, and a spherical shape part formed on the outer diameter surface side. The spherical shape part is opened on a small end surface side of the holder for a ball bearing, and has a circular arc part contacting with the ball. Both end points forming the circular arc part are positioned on the small end surface side with respect to the center line in a width direction of the pocket.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a cage and a ball bearing used for a ball bearing such as a radial ball bearing or an angular ball bearing.

In the field of ball bearings, a cage is used to hold a plurality of balls, which are rolling elements, at equal intervals between an outer ring and an inner ring.
Conventional retainer 100, pockets P ₀ for accommodating the balls are rolling elements, as shown in Figure 6, the sliding contact S ₁ positioned on the side of the large end face 81 of the center line P _C in the width direction of the pocket, and S _2, was to hold the ball at three points by the center line P _C sliding contact S ₃ of the small end face 80 side located on the opposite side of the hand.
Here, the large end surface of the cage means the end surface on the side where the outer diameter of the cage is large, and the small end surface means the end surface on the side where the outer diameter of the cage is small.
Such a three-point holding structure has a problem that the holding force of the balls is weak.
Patent Document 1 discloses a cage in which a pocket shape is formed on a cylindrical surface and a protrusion is provided in the vicinity of the outer diameter.
Patent Document 2 discloses a technique for preventing a whirling motion by covering the inner surface of a pocket with a synthetic resin liner, and makes the pitch circle diameter of the pocket and the pitch circle diameter of each rolling element different from each other. It is described.
However, since the technology disclosed in the publication permits relative displacement between the pockets in order to prevent shake, it cannot be said that the holding force of the balls is sufficient.

Japanese Patent Laid-Open No. 10-169658 JP 2006-144984 A

  An object of the present invention is to provide a cage excellent in strengthening and stability of a ball holding force in a ball bearing, and a ball bearing using the cage.

The ball bearing retainer according to the present invention is a ball bearing retainer having an outer diameter surface and an inner diameter surface, and pockets for holding the balls are arranged in a ring shape, wherein the pocket is the inner diameter surface. A cylindrical portion formed on the side and a spherical shape portion formed on the outer diameter surface side, and the spherical shape portion opens on the small end surface side of the ball bearing retainer and is slidably in contact with the ball The both end points forming the arc portion are located on the small end face side of the center line in the width direction of the pocket.
Therefore, the ball is held so as to be in sliding contact with the spherical surface inside the arc portion.

The present invention may be set smaller than the pitch circle diameter PCD _B pitch circle diameter PCD _P of the ball of the ball holding center of the pocket (claim 2).
The retainer example, made of a material having elasticity such as nylon, in this way the pitch circle diameter PCD _P of the ball holding center of the pocket is set to be smaller than the pitch circle diameter PCD _B of each ball in the bearing, the arcuate portion The ball is held so as to be pressed against the inner ring by the inner spherical surface.
Therefore, the ball bearing rotates at a high speed and is stably held so as to be pressed even if a centrifugal force is applied to each ball.
Further, in the conventional cage, if the outer ring is expanded in diameter due to thermal expansion or the like, a gap may be formed between the outer ring and the cage according to the present invention. And can be held so as to press against the inner ring side.
The cage according to the present invention can be applied to radial ball bearings, angular ball bearings, and the like.

  Since the cage according to the present invention holds the ball so as to be held by the entire arc portion of the spherical shape portion, the holding force is strong and stable as compared with the conventional three-point holding structure.

(A) shows the partial external view of the holder | retainer based on this invention, (b) shows a pocket shape. The perspective view of the state where the ball was held in the pocket is shown. (A) is a cross-sectional view taken along the line ZZ shown in FIG. 2, (b) is a plan view of the pocket, (c) is a cross-sectional view taken along the line WW shown in (b), and the positional relationship between the outer ring and the inner ring. Indicates. The front view and side view of the holder | retainer which concern on this invention are shown. 4A is a view in FIG. 4, FIG. 4B is a view in B, FIG. 4C is a view in C, and FIG. The example of the pocket shape of the conventional cage | basket is shown.

  An example in which the cage according to the present invention is applied to an angular ball bearing will be described below, but the present invention is not limited to this embodiment.

As shown in FIG. 4, the cage 10 has a ring shape having an outer diameter surface 11 and an inner diameter surface 12, a large end surface 41 on a relatively large outer diameter side, and a small end surface 40 on a smaller outer diameter side. Have
FIG. 5 shows the A-D view, FIG. 1A shows a partial perspective view, and FIG.
The cage 10 is preferably manufactured using an elastic resin material such as nylon.
As shown in FIG. 3C, the cage 10 has a plurality of balls 20 arranged as rolling elements between the outer ring 31 and the inner ring 32, and these balls 20 are held by the cage 10 at equal intervals. .
As shown in FIGS. 1B and 5, the pocket P is formed in a cylindrical portion 13 formed of a cylindrical surface on the inner diameter surface side, and a spherical shape portion 14 formed of a spherical surface on the outer diameter surface side.
The spherical shape portion 14 is open to the small end surface 40 side, and the portion that holds the ball 20 has the shape of the arc portion 15.
As shown in FIG. 3A, the arc portion 15 holds the ball 20 in the spherical shape portion 14 so as to be held in sliding contact as a whole.
Further, two end points (start point and end point), respectively 16a (a position corresponding to the _{S 1} of the conventional retainer 100 illustrated in FIG. 6) of the arcuate portion 15, 16b (conventional cage shown in FIG. 6 If the position) corresponding to _{S 2} of 100, two end points 16a, as shown in FIG. 1 (b), 16b, based on the center line _{P C} in the width direction of the pocket P, both small cage 10 It is located on the end face 40 side.
Further, as shown in FIG. 5A, the central angle θ on the arc portion 15 side indicated by the flange 16a O 16b exceeds 180 °.
In other words, the fact that the central angle on the side of the arc that slides into contact with the ball exceeds 180 ° is described with reference to FIG. 5A. The ball is held so as to be held by the arc 15 and the center of the arc 15 It means that the angle θ exceeds 180 °.

The pitch circle diameter PCD _P of the ball holding center of the pocket P of the retainer 10 and have set to be smaller than the pitch circle diameter PCD _B of each ball as shown in FIG. 3 (a), the balls 20 inner ring It is held so as to press against the 32 side.
Thereby, even if a centrifugal force acts on the ball 20 or the outer ring 31 expands in diameter due to thermal expansion or the like, the ball 20 is stably held.

  This embodiment is an example of an angular ball bearing as shown in FIG. 3 (c), and the diameter of the cage 10 is different on the left and right sides so as to avoid interference with the outer ring 31 and the inner ring 32, and a taper is provided between them. Although it is a connected shape, it is not limited to this embodiment as long as a combination of the cylindrical portion 13 and the spherical shape portion 14 is used.

10 cage 11 outer diameter surface 12 inner surface 13 cylindrical portion 14 spherical portion 15 arc portion 16a end point 16b endpoints 40 and 80 the width direction of the center line of the small end face 41, 81 the large end face P pocket _{P C} pocket

Claims (3)

A ball bearing retainer having an outer diameter surface and an inner diameter surface, wherein pockets for holding balls are arranged in a ring shape,
The pocket has a cylindrical portion formed on the inner diameter surface side and a spherical shape portion formed on the outer diameter surface side,
The spherical shape portion has an arc portion that is open to the small end face side of the ball bearing retainer and is in sliding contact with the ball, and both end points forming the arc portion are center lines in the width direction of the pocket. The ball bearing retainer is located closer to the small end surface than the ball bearing. Cage for a ball bearing according to claim 1, wherein the pitch circle diameter PCD _P is equal to or smaller than the pitch circle diameter PCD _B of the ball in the ball holding center of the pocket.   A ball bearing using the ball bearing retainer according to claim 1.

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