JPS643849Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to a small-diameter ball bearing used in relatively small machines such as audio equipment, video equipment, and miniature motors.

[Prior art]

Figure 1 is a sectional view of the main parts showing the general structure of a commonly used small-diameter ball bearing, where 1 is an inner ring, 2 is an outer ring,
3 is a ball interposed between the inner ring 1 and the outer ring 2;
5 is a cage for holding the balls 3, and 5 is a shield plate whose outer periphery is fitted into a seal groove 2a formed on the inner periphery on the end face side of the outer ring 2 via a snap spring 6, so that the inner periphery and the inner ring 1 are connected to each other. The bearing is sealed in a narrow and minute labyrinth gap 7 formed between the circumferential step portion 1a and a sealed ball bearing.

By the way, the generally used shield plate 5
In the small-diameter ball bearing described above, when the snap spring 6 is elastically tightly fitted into the seal groove 2a of the outer ring 2 in order to hold the shield plate 5 on the outer ring 2, the elasticity causes the bottom surface of the seal groove 2a to tighten on the outer peripheral surface. Furthermore, since the diameter of the outer ring 2 is small and the wall thickness of the outer ring 2 is thin, distortion occurs on the outer circumferential surface of the outer ring 2, impairing the roundness and cylindricity of the outer ring 2, reducing accuracy during use. There are drawbacks that affect the

[Purpose of invention]

This invention aims to provide a small-diameter ball bearing that can ensure the roundness and cylindricity of the inner and outer rings.

[Structure of the idea]

This invention is a small-diameter ball bearing consisting of an inner ring 10, an outer ring 20, a plurality of balls 30 housed between the inner and outer rings, and a cage 40 made of a polymer material that guides and holds the plurality of balls in a rolling manner. , the cage 40 has an annular base 41 and an inner surface of the annular base 41 that protrudes in the axial direction at equal intervals, and has a spherical ball holding section 43 at the center of both sides, and has a ball holding section 4.
A plurality of column parts 42 whose widths on both sides of No. 3 are narrowed toward the ends, and which have locking spherical protrusions 47 on the open side end faces, and a plurality of spherical protrusions 47 that are engaged with the spherical protrusions 47. An annular lid member 46 having a hole 48 on the inner surface, and grease sectors 44, 44 are formed between the pillar parts and on both sides of the ball holding part 43 at the center of the pillar part, expanding toward the ends, Both end surfaces of the cage 40 are extended to the ends of the inner and outer rings 10, 20, and the inner and outer peripheral surfaces of the cage 40 and the inner and outer rings 10, 2 are
The gist is that annular labyrinth gaps 50 and 60 that are wide in the axial direction and narrow in the radial direction are formed between the two.

〔Example〕

FIGS. 2 and 3 are drawings showing a small diameter ball bearing according to this invention. In the drawing, 10 is the inner ring,
20 is an outer ring, 30 is a plurality of balls interposed between the inner ring 10 and the outer ring 20, 40 is a retainer that holds the ball 30 between the inner and outer rings 10 and 20, and the ball 3
0, a labyrinth gap 50 that is wide in the axial direction and minute in the radial direction formed between the outer circumferential surface on both end surfaces of the inner ring 10 and the inner circumferential surface on both end surfaces of the outer ring 20. A labyrinth gap 60 that is wide in the axial direction and minute in the radial direction is formed between the
The bearing is sealed to form a sealed ball bearing.

The retainer 40 is made of a polymeric material such as nylon, and has a plurality of pillars 42 formed at equal intervals in the axial direction on the inner surface of an annular base 41 formed in a ring shape with a predetermined width. A spherical ball holding part 43 is provided at the center of both sides of the pillar part 42, and the ball holding part 4
Make the width of both sides of 3 narrower towards the end. Then, the space between each pillar part 42, 42 is slightly larger than the diameter D of the ball 30, and the entrance width S is set to the ball 30.
A spherical ball holding portion with a diameter slightly smaller than the diameter D of 0 is formed, and grease sectors 4 are formed in a substantially trapezoidal shape on both sides of the ball holding portion 43.
A comb-shaped retainer body 45 having 4 and 44 symmetrically
and a ring-shaped cover member 46 having a predetermined width dimension, which is attached to the open side end surface of the pillar portion 42 of this cage main body 45, and both are connected by a fastening structure described later. . That is, the cage body 4
A spherical protrusion 47 is provided on the open side end surface of the column portion 42 of No.
When the spherical protrusions 47 are press-fitted into the spherical holes 48 during fastening, the retainer body 45 and the lid member 46 are integrally connected.

In the case of the small diameter ball bearing of this invention, the cage 40
Since the grease sectors 44, 44 provided on both sides of the ball holding portion 43 are filled with grease, the inside of the ball socket can be smoothly lubricated for a long period of time. In addition, the cage 40, the inner ring 10, and the outer ring 20
Since the bearing is sealed in the labyrinth gaps 50 and 60 formed between the inner and outer circumferential surfaces on both end faces of the outer ring 20, the conventional shield plate can be omitted, and this prevents distortion from occurring on the outer circumferential surface of the outer ring 20. Thereby, the roundness and cylindricity of the outer ring 20 can be ensured. Furthermore, in the present invention, the open side end surface of the column is spherical and has a small diameter, so the column can be easily guided between the balls, and the open side end between the columns can be expanded. Since the base of the column is thin, the column easily deforms when the ball is inserted, making it easy to assemble the retainer and the balls.

[Effect of idea]

According to this invention, it is possible to prevent distortion of the bearing ring due to the installation of the shield plate and ensure roundness and cylindricity, thereby improving bearing performance, especially for small-diameter ball bearings with thin bearing rings. In some cases, significant effects can be obtained.

[Brief explanation of the drawing]

Figure 1 is a sectional view of the main parts of a conventional small-diameter ball bearing.
FIG. 2 is a cross-sectional view of the main part of the small-diameter ball bearing according to this invention, and FIG. 3 is a partially expanded plan cross-sectional view of the balls and the holding portion. 10...Inner ring, 20...Outer ring, 30...Ball, 40
... Cage main body, 41 ... Annular base, 42 ... Pillar part, 4
3...Ball holding part, 44...Grease sector, 4
5... Cage main body, 46... Lid member, 47... Spherical protrusion, 48... Spherical hole.

Claims (1)

[Scope of utility model registration request] A small-diameter ball bearing consisting of an inner ring, an outer ring, a plurality of balls housed between the inner and outer rings, and a cage made of a polymer material that guides and holds the plurality of balls in a rolling manner, the cage being attached to an annular base. and protrudes from the inner surface of the annular base at equal intervals in the axial direction, and has a spherical ball holding portion at the center of both sides, and the width of both sides of the ball holding portion is narrowed toward the end, and , consisting of a plurality of pillars having locking spherical protrusions on the open side end surface, and an annular lid member having a plurality of spherical holes on the inner surface to be locked by the spherical protrusions, and between the pillars. and forming grease sectors on both sides of the ball holding part in the center of the pillar part, which spread toward the ends,
Extending both end surfaces of the cage to the ends of the inner and outer rings,
A small-diameter ball bearing characterized by forming an annular labyrinth gap that is wide in the axial direction and narrow in the radial direction between the inner and outer circumferential surfaces of a cage and the inner and outer rings.