JPH04236820A - Cage for rolling bearing - Google Patents

Abstract

PURPOSE:To obtain a two-divided-pieces type cage for a bearing, which is made of resin impregnated complex material including fiber and is easily machined and is large in its strength. CONSTITUTION:A cage made of resin impregnated complex material including fiber therein is divided into two parts in the peripheral direction. One of these half part 1' is provided with pockets 2 for receiving balls X and holes 3 for joint. A cage 1 is formed by jointing together the two pieces of these half parts 1' opposed to each other by rivets (not shown in the right figure).

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-part cage for rolling bearings made of resin molded material.

0002

BACKGROUND OF THE INVENTION In recent years, in manufacturing rolling bearings, the use of resin instead of iron-based or brass-based cage materials has rapidly progressed in order to reduce weight and cost. The resin used is mainly thermoplastic resin, which can be easily molded into complex shapes by injection molding, and there are various engineering plastics (abbreviated as engineering plastics), but those with particularly high heat resistance and strength are used. Laminated reinforced thermosetting resin, thermoplastic resin impregnated with medium-length fibers, or prepreg using thermosetting resin
reg) and sheet molding compound (SM
Resin-impregnated composite materials such as C) are attracting attention.

[0003] As an example of a cage manufactured using the above laminated reinforced resin, one disclosed in Japanese Patent Application Laid-open No. 113820/1982 is known. This cage is comprised of a cage ring made of a laminated composite material made of a woven fabric and a sheet of organic material impregnated with a solid lubricant, and provided with pockets at required intervals to support the balls. The ball pocket is provided by machining.

0004

[Problems to be Solved by the Invention] In the conventional cages described above, injection molding of laminated reinforced resins and resin-impregnated composite materials is difficult because they contain laminated materials and medium/long fibers. The raw material is formed and the ball pocket is machined by cutting. However, in such a conventional retainer, the pocket holes are formed by cutting, so that some of the reinforcing fibers in the pocket holes are oriented in a direction perpendicular to the balls and come into direct contact with the balls. Reinforcing fibers such as carbon fibers and glass fibers are extremely hard, which increases the damage and wear on the ball.

Furthermore, since pocket holes are formed by cutting, the mechanical strength of the material itself is reduced.

Furthermore, there is a lot of waste of material due to cutting,
There is also the problem of high processing costs.

[0007] This invention was made in view of the various problems of the conventional cages for rolling bearings mentioned above, and its purpose is to use a resin-impregnated composite material, which has conventionally been difficult to injection mold, and to simplify the processing process. To provide a cage which is small in size, eliminates waste of material, has high strength, and can reduce wear of balls in pocket holes.

[0008]

[Means for Solving the Problems] In order to solve the above problems, the present invention consists of a resin-impregnated composite material containing fibers,
A bearing cage in which ball pockets are provided at predetermined intervals is divided into two halves in the circumferential direction, and a pair of halves are joined by a joining means to form a rolling bearing cage.

The resin-impregnated composite material may be a polyimide-based resin-impregnated composite material containing glass fibers. Alternatively, the resin-impregnated composite material may be an epoxy resin-impregnated composite material containing glass fibers. The joining means may be riveting means. Alternatively, the joining means may be a fitting member consisting of a concavo-convex member provided on the surfaces where the halves of the cage face each other.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to the drawings. FIGS. 1(a) and 1(b) show an example of a cage 1 using rivets as the joining means. (a) is a side view, (
b) is a plan view. The cage 1 consists of two halves 1' and 1' divided in the circumferential direction, and the cage 1 is provided with ball pockets 2 at predetermined intervals, and a rivet is inserted between each pocket. Rivet holes 3, 3 for
is provided. The two halves 1', 1' are faced to each other and a rivet (not shown) is inserted into the rivet hole 3 to join them.

FIGS. 2(a) and 2(b) show an example of a cage 1 in which a fitting member 4 is used as the joining means. The cage 1 itself is shown in Figure 1.
This is basically the same as the example. The fitting member 4 is the retainer 1
The two half portions 1' are composed of a band-shaped convex portion 4a and a concave portion 4b formed on surfaces facing each other. Convex portion 4a and concave portion 4
b are provided alternately in opposite directions with the balls X held in the cage in between (see figure (b)). When providing the fitting member 4 in this way, if the number of balls X is even, 2
The two halves 1' can be made from one mold and placed facing each other. When the number of balls X is odd, two half portions 1' are formed using two molds in which the projections 4a and recesses 4b of the fitting member 4 are arranged symmetrically.

[0012] The material used for the cage 1 described above is one of two types: sheet molding compound (SMC) and prepreg. SMC is a polyimide-based resin-impregnated composite material containing 60% glass fiber. Also, prepreg is made of 50% glass fiber.
It is an epoxy resin-impregnated composite material containing. Its mechanical properties are as follows. S
MC prepreg
Bending strength room temperature 4400kg
/cm2 Room temperature 6000kg/cm
2 150℃
3200kg/cm2 120℃
5200kg/cm2
200℃ 2600kg/cm2
Tensile strength room temperature 2100kg
/cm2 Room temperature 5100kg/cm
2 200℃
1800 kg/cm2 FIG. 3 shows an outline of the manufacturing method of the cage. As shown in (a), in this method, first, a ring-shaped sheet material 1X made of a resin-impregnated composite material containing fibers is prepared. Then, this sheet material 1X is heated and compression molded using a suitable mold to form a half portion 1' which is obtained by dividing the thickness of the cage into two. Reference numeral 2 denotes pockets provided at appropriate intervals, into which the ball X is fitted. Next, the cage 1 is formed by joining the two half parts 1' facing each other so that the pocket 2 is formed inside by a joining means.

[0013] The joining means may be fusion bonding, adhesion, riveting (so-called rivets), or fitting. For fusing or adhesion, opposing surfaces of the halves are joined using a thermosetting adhesive or varnish. Ultrasonic welding is used for fusion. When a cage is formed by such a method, a cage with the following characteristics can be obtained.

(1) A thin resin skin layer is formed on the surface of the molded product, and in principle, 100% of the fibers are oriented in a plane parallel to the surface. (2) There is no waste of resin material, unlike when a ball pocket hole is formed by cutting out a molded material. (3) Extra machining processes, such as cutting out pocket holes and subsequent deburring, can be omitted. (4) Highly filled medium-length fibers of glass fiber or carbon fiber can be used, and a resin retainer for a bearing with extremely high strength can be obtained. (5) The space occupied by the cage inside the bearing can be smaller than that of conventional thermosetting laminated resin cages. Therefore, more lubricating grease can be enclosed, which is very advantageous for bearing life.

[0015]

[Effects] As explained in detail above, in the cage according to the present invention, two halves of the cage formed using a sheet material of a resin-impregnated composite material containing fibers are joined by a joining means. Compared to conventional cages, which are formed by cutting out pocket holes in the roll-shaped composite material that is difficult to injection mold, this structure requires fewer processing steps, eliminates wasted material due to cutting out, and is easier to form. The orientation of the fibers in the pocket holes of the retainer becomes parallel to the surface, reducing scratches and wear on the balls. Furthermore, since no machining is required, various advantages such as high strength can be obtained.

[Brief explanation of the drawing]

[Figure 1] Diagram showing the side and plane sides of a retainer joined by riveting

[Fig. 2] Cross-sectional view of a cage joined by a fitting member

[Figure 3] Explanatory diagram of the cage manufacturing method

[Explanation of symbols]

1 Cage 1’ half part 2 Pocket 3 Rivet hole 4 Fitting member

Claims (5)

[Claims] [Claim 1] A bearing retainer made of a resin-impregnated composite material containing fibers and having ball pockets provided at predetermined intervals is divided into two halves in the circumferential direction, and a pair of halves are joined by a joining means. Cage for rolling bearings. 2. The cage for a rolling bearing according to claim 1, wherein the resin-impregnated composite material is a polyimide-based resin-impregnated composite material containing glass fiber. 3. The cage for a rolling bearing according to claim 1, wherein the resin-impregnated composite material is an epoxy resin-impregnated composite material containing glass fiber. 4. The rolling bearing cage according to claim 1, wherein the joining means is a riveting means. 5. A cage for a rolling bearing according to claim 1, wherein the joining means is a fitting member made of a concave and convex member provided on surfaces where half portions of the cage face each other.