JPS641535Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial field of application The present invention is a ball cage for ball bearings, especially a self-lubricating synthetic resin cage for ball bearings used in places where normal lubricants cannot be used, such as in a vacuum. Regarding.

Conventional technology Synthetic resin cages for ball bearings are manufactured by Jikaisho, for example.
As shown in Figures 1 and 2 of Japanese Patent No. 57-56219, a crown-shaped retainer is known in which pockets into which balls can be inserted from the axial direction are formed at one end of a synthetic resin ring at equal intervals around the circumference. There is.

Problems that the invention aims to solve: When this type of cage is used for ball bearings used in places where normal lubricants cannot be used, such as in vacuum, it is difficult to use self-lubricating materials, as well as when the cage material does not have self-lubricating properties. Even if the cage material is
This material has difficulty adhering to the surface of the balls and the raceway surface of the raceway ring, and does not form a sufficient transfer film, resulting in a lack of lubrication at the contact surface between the balls and the raceway surface, leading to early failure of the bearing. .

Means for Solving the Problem The present invention solves the above problem by forming a plurality of protrusions 5 on the spherical inner wall 4 of the pocket 3 for the ball 6, and pressing the protrusions 5 against the ball 6 in the pocket 3. This problem is solved by a self-lubricating synthetic resin cage for ball bearings.

The cage material is a self-lubricating synthetic resin, such as a fluorine resin. Moreover, the protrusion 5
are formed at symmetrical positions with respect to the center line of the pocket 3.

Function In the above configuration, the balls 6 are held in pressure contact with the protrusions 5 in the pocket 3 in a preloaded state, so that during the initial rotation of the ball bearing, the contact surface of the protrusions 5 with the balls 6 is The self-lubricating synthetic resin such as fluororesin that is scraped off by the balls 6 adheres to the surface of the balls 6 and the raceway surface of the raceway ring, forming a transfer film of synthetic resin material, which creates a gap between the balls 6 and the raceway surface. Lubricate. In this way, the protrusion 5 is gradually shaved off and its protrusion height is reduced, so that the amount of preload applied to the ball 6 by the protrusion 5 is reduced, and an appropriate amount of pressure is created between the ball 6 and the inner wall 4 of the pocket 3. A gap is formed.
After a suitable gap is formed between the balls 6 and the inner wall 4 of the pocket 3, large transfer of the cage material does not occur as in the initial stage of rotation, and the transfer film is formed little by little, and the transfer film continues for a long time. Keep bearings lubricated over time.

Embodiment An embodiment of the present invention will be described with reference to the drawings. 1st
In the figures to FIG. 5, a synthetic resin retainer 1 for ball bearings is made of a self-lubricating synthetic resin, such as fluororesin, and has a pocket 3 for balls 6 on one end side of a synthetic resin ring body 2. are formed at equal intervals around the circumference, a plurality of protrusions 5 are formed on the spherical inner wall 4 of the pocket 3, and the protrusions 5 apply an appropriate preload to the balls 6 in the pocket 3. It is a shaped synthetic resin cage. 7 is a pocket opening formed at one end of the ring body 2, and 8 is a claw projecting from the end surface of the ring body 2, forming the pocket opening 7. As shown in FIGS. 2 to 5, the projections 5 are positioned symmetrically with respect to the center line of the pocket 3 and on the bottom side (meaning the pocket bottom 9 with respect to the pocket opening 7 on one end side of the ring body 2). It is formed on the inner wall 4. Further, the shape of the surface of the protrusion 5 may be arbitrarily selected such as a convex spherical surface, a concave spherical surface, or a flat surface so as to meet the purpose of the present invention.

In the above configuration, as shown in FIGS. 4 and 5, the balls 6 are held in pressure contact with the protrusions 5 in the pocket 3 in a preloaded state, so that during the initial rotation of the ball bearing, the protrusions 5 The contact surface of ball 5 with ball 6 is scraped off by ball 6, and a self-lubricating synthetic resin material adheres to the surface of ball 6 and the raceway surface of the raceway ring to form a transfer film, and the contact surface between ball 5 and raceway surface is Lubricate.
In this way, the protrusion 5 is gradually shaved off and its protrusion height is reduced, so that the amount of preload applied to the ball 6 by the protrusion 5 is reduced, and an appropriate amount of pressure is created between the ball 6 and the inner wall 4 of the pocket 3. A gap is formed. ball 6
After an appropriate gap is formed between the inner wall 4 of the pocket 3 and the inner wall 4 of the pocket 3, large transfer of the cage material does not occur as in the initial stage of rotation, and the transfer film is formed little by little, and the transfer film is formed over a long period of time. Continue to lubricate the bearings.

Effect The present invention, as in the above structure, exhibits self-lubricating properties and lubricates the bearing with the transfer film of the synthetic resin material attached to the balls 6 and the raceway surface. This eliminates the poor lubrication that tends to occur during the initial rotation of lubricated ball bearings, improving bearing life. Further, since the formation of the above-mentioned transfer film continues even after the initial rotation of the bearing, a good lubrication condition continues between the balls 6 and the raceway surface, and the life of the bearing is further improved.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing a part of an embodiment of the present invention, Fig. 2 is an enlarged front view of a main part showing a part of Fig. 1, and Fig. 3 is a longitudinal cross-section of the embodiment with the ball held. 4 is a sectional view taken along the - line in FIG. 3, and FIG. 5 is a sectional view taken along the - line in FIG. 3. 1... Cage, 2... Ring body, 3... Pocket,
4... Spherical inner wall, 5... Protrusion, 6... Ball.

Claims (1)

[Scope of utility model registration request] A self-lubricating synthetic resin retainer for a ball bearing, in which a plurality of protrusions are formed on the spherical inner wall of a ball pocket, and the protrusions are brought into pressure contact with the balls in the pocket.