JP4424092B2 - Synthetic resin crown cage - Google Patents

Description

  The present invention relates to a synthetic resin crown-shaped cage used for ball bearings.

  Synthetic resin crown-shaped cages used for conventional ball bearings are provided with partition portions protruding in one axial direction at circumferential positions of the annular base body, and are substantially C-shaped when viewed from the radial direction between the partition portions. It is the structure which has a pocket for ball accommodation (for example, refer to patent documents 1). The pocket is opened toward one of the radial direction and the axial direction. The inner surface of the partition part, that is, the inner wall surface constituting the pocket has a spherical shape. In this crown-shaped cage, in order to make it difficult to come off from the ball of the ball bearing, the tip side of each partition portion is usually wrapped around the ball.

In the state where the conventional crown-shaped cage is used for, for example, a ball bearing, when the rotational centrifugal force increases with high-speed rotation, each partition portion is easily elastically deformed radially outward. The inner diameter side corner of the part interferes with the fast rotating part of the ball and is likely to wear out early.
Japanese Utility Model Publication No. 5-34317

  The present invention solves the problem of improving wear resistance in a crown-shaped cage made of a synthetic resin while inheriting a configuration in which it is difficult to come off from a ball bearing during high-speed rotation in a situation where it is used for a ball bearing. It should be a challenge.

The crown-shaped cage made of the synthetic resin of the present invention is provided with a partition portion protruding in one axial direction at a circumferential portion of the annular base body, and for accommodating a C-shaped ball as viewed from the radial direction between the partition portions. It has a pocket, the tip end side of the partition part expands with rotation, and the partition part elastically deforms radially outward in the radial direction, and the shape along the radial direction of the inner wall surface constituting each pocket is a spherical surface. In addition, a recess that avoids interference with a portion having the fastest rotation speed of the ball is provided at the inner diameter side corner of the inner wall surface, and the recess is pivoted from the center of each pocket at the inner diameter side corner of the inner wall surface. The axial length of the concave portion provided on both ends in the axial direction from the center of the pocket and formed on the distal end side of the partition portion is axially the other side in the axial direction from the center of the pocket. Axial length of the recess formed on the side The inner diameter side corner on one side in the axial direction with respect to the recess is formed so as to be in contact with a portion slower than the fastest portion of the ball rotation speed. .

  According to the present invention, when each partition portion is elastically deformed obliquely outward in the radial direction as the rotational centrifugal force increases in the state of being used for the ball bearing, the inner wall surface (the inner surface of the partition portion) ), The area where the inner diameter side corners abut the balls is reduced. Therefore, the frictional resistance can be reduced, and the worn part can also be reduced. In particular, the region where the recess is provided corresponds to a portion where the rotational speed of the ball is fast, and the inner diameter side corner portion of the inner wall surface does not need to come into contact with the fast rotational portion of the ball, thereby suppressing wear. This is advantageous. In this way, although the inner wall surface constituting the pocket of the crown-shaped cage and the ball are less likely to interfere with each other, the pocket is substantially C-shaped when viewed from the radial direction, and the inner diameter side corner on the tip side of the inner wall surface is Since it abuts in a state of being wrapped around the ball, it is possible to suppress or prevent the crown-shaped cage from being detached from the ball bearing. In addition, since the region where the ball rotates slowly is in contact with the portion that contacts the ball, that is, the inner diameter side corner on the tip side of the inner wall surface, wear of the contact portion is suppressed.

Preferably, the concave portion may be provided in a groove shape over the entire length in the circumferential direction on the inner diameter surface of the partition portion.

  According to the crown-shaped cage made of the synthetic resin of the present invention, it is possible to improve wear resistance while making it difficult to disengage from the ball bearing by the rotational centrifugal force in the situation where it is used for the ball bearing.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, the best embodiment of the invention will be described with reference to the drawings.

  First, with reference to FIG. 5 and FIG. 6, the deep groove ball bearing used as the use object of the synthetic resin crown-shaped cage is demonstrated. 5 is a perspective view of the deep groove ball bearing using the crown-shaped cage of FIG. 1 with a part cut away, and FIG. 6 is a cross-sectional view of the deep groove ball bearing of FIG.

  The deep groove ball bearing has a configuration in which a large number of balls 3 are interposed between the outer ring 1 and the inner ring 2 facing each other, and the large number of balls 3 are held at substantially equal intervals in the circumferential direction by a crown-shaped cage 4. The crown-shaped cage 4 is a ball guide type in which the ball 3 is rotated and guided by rolling.

  In addition, the outer ring | wheel 1, the inner ring | wheel 2, and the ball | bowl 3 are formed with metals, such as bearing steel and carburized steel, for example. The crown cage 4 is, for example, polyethylene, polyamide, polyacetal, polyethylene terephthalate, polybutylene terephthalate, polycarbonate, polyphenylene sulfide, polyethersulfone, polyetherimide, polyamideimide, polyetheretherketone, thermoplastic polyimide, thermosetting. It is formed of a synthetic resin such as polyimide, epoxy resin, or phenol resin.

The crown retainer 4 will be described in detail with reference to FIGS. FIG. 1 is a perspective view showing the best embodiment of the crown-shaped cage, FIG. 2 is a diagram of a part of the crown-shaped cage of FIG. 1 developed from the radial direction, and FIG. sectional view of the snap cage, Fig. 4, in FIG. 2 (4) - (4) line is an arrow cross-sectional view.

  The crown-shaped cage 4 is manufactured by molding a synthetic resin, and pockets 6 for inserting and holding the balls 3 are provided at several locations on the annular base body 5 at almost equal intervals. The pocket 6 is substantially C-shaped when viewed from the radial direction, and is open toward one of the radial direction and the axial direction.

  Partition portions 7 that protrude in one axial direction are provided at circumferential positions of the annular base body 5, and pockets 6 exist between the partition portions 7. A recess 8 is provided on the distal end side of the partition portion 7, and a bifurcated retaining portion 7 a exists on the distal end side of each partition portion 7 due to the recess 8. The pocket 6 is formed by being surrounded by a substantially semicircular semicircular portion 9 provided on the annular mother body 5 side and curved surface portions 10 and 10 provided on the retaining portion 7a side. A lubricant such as grease is stored in the recess 8.

  Here, let the shape along the radial direction of the inner wall surface (inner side surface of each partition part 7) which comprises each pocket 6 be a spherical surface. And the recessed part 11 which avoids interference with the part with the high rotational speed of the ball | bowl 3 in the internal diameter side corner | angular part of the said inner wall surface (inner side surface of each partition part 7) is provided. Specifically, the concave portion 11 is a region RB corresponding to a range in which a predetermined amount w1, w2 is expanded in the axial direction from the center P of each pocket 6 at the inner diameter side corner portion of the inner wall surface (inner side surface of each partition portion 7). Is provided. In this embodiment, the recessed part 11 is provided in groove shape over the circumferential direction full length in the internal diameter surface of each partition part 7. FIG.

  In the deep groove ball bearing shown in FIGS. 5 and 6, when the ball 3 rotates and revolves, as shown in FIG. 3, the point intersecting the radial line L passing through the center of the ball 3 on the outer surface of the ball 3. The rotation speed at X1 and X2 is the fastest, and the rotation speed at points X3 and X4 intersecting the axial line S passing through the center of the ball 3 on the outer surface of the ball 3 is zero. The center of the ball 3 is matched with the pocket center P. In the ball 3, the rotation speed is slower as the position approaches the points X3, X4 from the points X1, X2. The portion with the fastest rotation speed of the ball 3 abuts on the inner surface of each partition 7 of the crown-shaped cage 4 at a position corresponding to the center P of the pocket 6 or the vicinity thereof. However, the crown-shaped cage 4 has a predetermined clearance in the axial direction and the circumferential direction between the inner surface of each partition 7 of the crown-shaped cage 4 and the outer surface of the ball 3. Since there is a deviation in the axial direction in the axial direction during the rotation operation, the portion where the rotation speed of the ball 3 is the fastest may be shifted in the axial direction from the position corresponding to the center P of the pocket 6 on the inner surface of each partition portion 7. is there.

  The formation position of the recess 11 and the axial width RB were determined based on the knowledge described below.

  In general, as shown in FIGS. 8A, 8B, and 8C, in the crown-shaped cage 4, as the rotational speed increases, the amount of elastic deformation of each partition 7 increases. The gap in the radial direction between the inner diameter side corner of each partition 7 and the ball 3 is clogged, and the interference area between each partition 7 and the ball 3 is expanded. FIG. 8 shows a result of using a conventional crown-shaped cage in which the concave portion 11 is not provided. That is, in the low speed rotation region, as shown in FIG. 8A, the tip side slightly interferes with the ball 3 from the center P of each partition portion 7. In the medium speed rotation region, as shown in FIG. 8B, the tip side from the center P of each partition portion 7 interferes with the ball 3 with a predetermined width. In the high-speed rotation region, as shown in FIG. 8C, the tip side and the base side sandwiching the center P of each partition 7 interfere with each other with a predetermined width. As described above, at the time of low speed rotation, the ball 3 interferes with the ball 3 on the tip side from the center P of each partition portion 7, but straddles the tip side and the base side sandwiching the center P of each partition portion 7 as the rotation speed increases. A wide area will interfere. The formation position of the recess 11 and the axial width RB are specified in consideration of the interference area during high-speed rotation.

  In such a crown-shaped cage 4, in a state where it is used for a deep groove ball bearing, each partition portion 7 is elastically deformed radially outward in accordance with an increase in rotational centrifugal force. The area where the inner diameter side corner of the portion 7 contacts the ball 3 can be reduced. Therefore, the frictional resistance can be reduced, and the worn part can also be reduced.

  With reference to FIG. 7, the operation in the case of using the crown-shaped cage 4 will be described.

  The crown-shaped cage 4 is in a state of being incorporated in a deep groove ball bearing as shown in FIGS. Since the crown-shaped cage 4 is in the form of a ball guide, the crown-shaped cage 4 is basically not in contact with the outer ring 1 or the inner ring 2 during the rotation operation. Rolls in contact with the inner wall surface forming the pocket 6 of the crown-shaped cage 4.

  Here, as the rotation speed increases, as shown in FIG. 7, when each partition portion 7 of the crown-shaped cage 4 is elastically deformed radially diagonally outward, each partition portion 7 elastically deformed radially diagonally outward. Although there is a possibility that the inner diameter side corner on the tip side of the ball may interfere with the ball 3, the presence of the recess 11 prevents the ball 3 from coming into contact with the portion having a high rotation speed. Thus, although the interference part of the inner wall surface which comprises the pocket 6 of the crown shape holder | retainer 4 and the ball 3 is reduced, the pocket 6 is made into a substantially C shape seeing from radial direction, and the front end side of each partition part 7 Since the inner diameter-side corners of the ball are in contact with the balls 3, the crown-shaped cage 4 can be prevented or prevented from coming off from the deep groove ball bearing. In addition, since a region where the rotation speed of the ball 3 is slow contacts the portion of each partition portion 7 that contacts the ball 3, that is, the inner diameter side corner portion on the tip side of each partition portion 7, the wear of this contact portion is reduced. It is suppressed.

  As described above, the crown-shaped cage 4 of the present invention can suppress early wear even when used at a high speed rotation in which the rotational centrifugal force increases, thereby improving the rolling characteristics and life of the deep groove ball bearing. Can contribute.

  Hereinafter, other embodiments of the present invention will be described.

  In the above embodiment, the recess 11 provided in the inner diameter side corner of each partition 7 of the crown-shaped cage 4 is provided in the entire length in the circumferential direction on the inner diameter surface of each partition 7, but for example, as shown in FIGS. As such, it can be partially provided. In FIG. 9, the recesses 11 are provided so as to be recessed only at the inner diameter side corners on both sides in the circumferential direction of the partition portions 7. In FIG. 10, the recess 11 is provided by being partially recessed, but has a tapered shape.

The perspective view which shows the best embodiment of the crown shaped holder | retainer based on this invention Fig. 1 shows a part of the crown-shaped cage in Fig. 1 as seen from the radial direction. Sectional view of the crown-shaped cage of FIG. FIG. 2 (4)-(4) sectional view taken along the line 1 is a perspective view showing a deep groove ball bearing using the crown-shaped cage of FIG. Sectional view of the deep groove ball bearing of FIG. The figure explaining that a trouble does not arise in the deep groove ball bearing of FIG. FIG. 5 is a diagram for explaining the amount of elastic deformation of the crown-shaped cage and the interference area with the ball in the deep groove ball bearing of FIG. FIG. 4 is a view corresponding to FIG. 4 in another embodiment of the crown-shaped cage according to the present invention. FIG. 4 is a view corresponding to FIG. 4 in still another embodiment of a crown-shaped cage according to the present invention.

Explanation of symbols

3 ... ball 4 ... crown cage 5 ... annular base 6 ... pocket 7 ... partition 11 ... concave

Claims (2)

A partition portion protruding in one axial direction is provided at a number of circumferences of the annular base body, and a C-shaped ball receiving pocket is provided between the partition portions when viewed from the radial direction. A crown-shaped cage made of a synthetic resin whose side is expanded in diameter and elastically deformed radially outward in the partition part,
The shape along the radial direction of the inner wall surface constituting each pocket is a spherical surface,
And, in the inner diameter side corner of the inner wall surface, provided with a recess to avoid interference with the fastest part of the ball rotation speed,
The recess is provided both axially from the center of each pocket at the inner diameter side corner of the inner wall surface,
The axial length of the concave portion formed on the distal end side of the partition portion which is one axial direction from the center of the pocket is formed on the base side of the partition portion which is the other axial direction from the center of the pocket. It is formed longer than the axial length of the concave portion, and is formed so that the inner diameter side corner portion on the one axial side of the concave portion is in contact with a portion slower than the fastest portion of the ball rotation speed. This is a crown-shaped cage made of synthetic resin.   The said recessed part is provided in groove shape over the circumferential direction full length in the internal diameter surface of the said partition part, The synthetic resin crown-shaped cage | capacitor of Claim 1 characterized by the above-mentioned.

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