JPH10311338A - Synthetic resin-made holder for roller bearing and manufacture therof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a synthetic resin-made holder for a roller bearing, sufficiently displaying an effect of reinforcing material, and difficult in generating damage or the like, in the synthetic resin-made holder using the reinforcing material of glass fiber or the like. SOLUTION: In the case of manufacturing a synthetic resin-made holder for a roller nearing by injection molding a synthetic resin charged with reinforcing material of glass fiber or the like in a metal mold, a gate G of the synthetic resin injecting metal mold is arranged in a position facing a cavity inside in a side of a ring part 1a in the vicinity of a boundary between the ring part 1a and a pillar part 1b of the holder, and injection molding is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synthetic resin cage for a roller bearing, and more particularly to a synthetic resin cage for a roller bearing manufactured by injection molding using a synthetic resin filled with a reinforcing material such as glass fiber. And its manufacturing method.

[0002]

2. Description of the Related Art A cage made of synthetic resin for a roller bearing is manufactured by injection molding using a mold. In that case, as shown in FIG. 3, the gate G is arranged at a position in the middle of the pillar 11b of the synthetic resin cage 11. In this case, the synthetic resin mold is formed between the inner mold 12 and the outer mold 13 as shown in FIG.
Location (there may be multiple locations), usually the inner mold 1
The gate G is exposed from 2 and a synthetic resin in a molten state is injected to perform injection molding.

In recent years, in order to increase the strength of a synthetic resin cage for a roller bearing, injection molding is often performed using a synthetic resin in which a raw material of the synthetic resin is filled with a reinforcing material such as glass fiber. That is, when the glass fiber is injected from the gate G of the inner mold 12 together with the synthetic resin in the molten state, the synthetic resin filled with the glass fiber injected from the gate G moves right and left in the cavity 14. At the position where they divide and flow at substantially equal distances, they join at a point where the welds are formed, and then a synthetic resin cage reinforced with glass fibers is formed. Even if such a synthetic resin cage 11 is subjected to any impact or force from the outside to each part, the inside is reinforced with glass fiber, so that the cage is strong against the impact and hardly generates cracks and the like.

[0004]

FIG. 5 is a partial cross-sectional view of a column portion of a conventional synthetic resin cage for a roller bearing containing reinforcing fibers (reinforcing material). When the retainer 11 is manufactured by injection molding, the position of the gate G is usually provided in the middle of the pillar portion 11b on the inner diameter side. However, in such a synthetic resin cage 11 formed of a material filled with a reinforcing material such as glass fiber, the orientation of the glass fiber 2 is perpendicular to the inner surface 11c, so that the glass
There is a problem that the reinforcing effect near the position G is thin. In addition, since welds are formed in similar portions of other pillars, when a force is applied to the pillars due to roller skew or advance / delay, breakage is likely to occur starting from the gate portion G or the weld portion. There is a problem.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-described problems, and is a synthetic resin cage using a reinforcing material such as glass fiber. It is an object of the present invention to provide a cage made of synthetic resin for roller bearings, which is unlikely to cause such problems.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a roller bearing synthetic resin holder formed by injection molding a synthetic resin filled with a reinforcing material such as glass fiber into a mold. In the container, the gate of the synthetic resin injection mold is arranged at a position facing the inside of the cavity on the ring portion side near the boundary between the ring portion and the column portion of the retainer and injection-molded. .

Further, in a method of manufacturing a synthetic resin cage for a roller bearing, which is formed by injection molding a synthetic resin filled with a reinforcing material such as glass fiber into a mold, a gate of the synthetic resin injection mold is provided. It is characterized in that the cage is arranged at a position facing the inside of the cavity on the side of the ring near the boundary between the ring and the column of the cage, and injection molding is performed.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an overall perspective view of a synthetic resin cage (hereinafter, referred to as a synthetic resin cage) 1 for a roller bearing according to the present invention. FIG. 2 (A)
FIG. 2B is a partial cross-sectional plan view of a pillar portion of the synthetic resin cage for a roller bearing of the present invention, and FIG. 2B is an inside front view. The synthetic resin cage 1 is manufactured by injection molding a synthetic resin filled with glass fiber 2 as a reinforcing material such as glass fiber into a mold. In this case, the gate G for injecting the synthetic resin provided in the mold is provided.
Are located at the ring part (annular part) 1a and the column part 1b of the cage.
Is provided on the side of the ring 1a near the boundary with.

That is, when the synthetic resin cage 1 is injection-molded, the position of the gate G of the mold is the inner mold as in the case shown in FIG. And pillar 1b
On the side of the cavity near the boundary with the ring portion 1a (closer to the ring portion). When the synthetic resin filled with glass fiber in a molten state is injected from the gate G in this manner, the gate G
The synthetic resin filled with a reinforcing material such as glass fiber 2 injected from above flows and merges in the cavity while being divided into right and left, and eventually solidifies to form a synthetic resin cage reinforced with glass fiber 2. In this case, as shown in FIG. 2A, the column 1 on the side of the ring 1a constituting the synthetic resin cage.
Near the boundary with b, the short glass fiber 2 of the reinforcing material in the synthetic resin is solidified while being oriented in the direction perpendicular to the inner surface 1c of the retainer 1.

As described above, the position of the gate G provided on the inner mold is located at the end face of the cavity at the boundary between the ring portion 1a and the column portion 1b, and the glass fiber 7 in the synthetic resin is
Even if it is solidified in a direction perpendicular to the column 1b, the position is on the ring 1a side, so that the column 1b does not easily break. Further, even if any impact or force is applied to the column 1b, it can be absorbed by deformation of the column 1b.

Incidentally, in the synthetic resin cage 1,
Even if the position of the gate G for injecting the synthetic resin is provided in the vicinity of the boundary between the ring portion 1a and the column portion 1b and on the end face of the cavity which becomes the ring portion 1a, the gate G inside the other resin portion is solidified. The glass fiber 2 does not extend in the vertical direction of the pillar portion, but is always solidified in a state of reinforcing the pillar portion. The gate G provided on the mold may be provided at one place or at several places such as three places. The cage made of synthetic resin for roller bearings and the method of manufacturing the same can be applied not only to cages for cylindrical roller bearings, but also to cages for tapered roller bearings and needle roller bearings.

In the above embodiment, a specific synthetic resin having a high mechanical strength, for example, a resin obtained by filling a polyamide resin such as nylon 66 with a reinforcing material such as glass fiber is used. Glass fiber, carbon fiber, fibrous wollastonite (wollastonite), silicon carbide fiber, boron fiber, alumina fiber, Si
-Ti-CO fiber, metal fiber (copper, steel, stainless steel), aromatic polyamide (aramid) fiber, potassium titanate whisker, graphite whisker, silicon carbide whisker, silicon nitride whisker, alumina whisker, etc. Can be If necessary, an elastomer may be used. The specific mixing ratio of the elastomer and the reinforcing fiber is omitted. Examples of the elastomer include natural rubber or butadiene rubber, isoprene rubber, styrene-butadiene copolymer rubber, acrylonitrile-butadiene copolymer rubber, chloroprene rubber, ethylene-propylene rubber, ethylene-propylene-diene rubber, and ethylene-propylene-butadiene copolymer. Rubber, synthetic rubber such as ethylene-ethyl acrylate copolymer rubber, and thermoplastic elastomers such as styrene, olefin, urethane, polyester, polyamide, and polyvinyl chloride.

[0013]

As described above in detail, according to the cage made of synthetic resin for a roller bearing of the present invention, the strength is increased,
Even if an impact or a load is applied to the rotating column portion of the bearing from the roller side for some reason, damage to the cage can be prevented.

[Brief description of the drawings]

FIG. 1 is an overall perspective view of a synthetic resin cage of the present invention.

FIG. 2 (A) is a partial cross-sectional plan view of a pillar portion of the synthetic resin cage of the present invention, and FIG. 2 (B) is an inside front view.

FIG. 3 is a partial perspective view of a conventional synthetic resin cage for a roller bearing.

FIG. 4 is a partial cross-sectional view of a mold when injection molding a conventional synthetic resin cage.

FIG. 5 is a side view of a pillar portion of a conventional synthetic resin cage, showing an orientation state of reinforcing fibers.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 synthetic resin retainer 1a synthetic resin retainer ring 1b pillar 2 glass fiber G gate for injection of synthetic resin

Claims (2)

[Claims] In a cage made of synthetic resin for roller bearings, which is formed by injection molding a synthetic resin filled with a reinforcing material such as glass fiber into a mold, the gate of the mold for injecting the synthetic resin is connected to the retainer. A synthetic resin cage for roller bearings, wherein the cage is arranged at a position facing the inside of the cavity on the side of the ring near the boundary between the ring and the column and injection molded. 2. A method of manufacturing a synthetic resin retainer for a roller bearing, which is formed by injection molding a synthetic resin filled with a reinforcing material such as glass fiber into a mold. A method for manufacturing a cage made of synthetic resin for roller bearings, wherein the cage is arranged at a position facing the inside of the cavity on the side of the ring near the boundary between the ring and the column of the cage.