JPH0719253A - Manufacturing method of bearing with resin ring - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] It is an object of the present invention to provide a method of manufacturing a bearing with a resin ring capable of preventing creep and spin phenomena. By achieving this object, it is possible to provide a high quality, low cost bearing having an extremely simple and novel structure. [Structure] A groove for ring fitting is engraved at a predetermined position of a bearing outer ring, and in a separate step, a C-shaped resin ring or an O-shaped resin ring having an inner diameter to be fitted in the ring fitting groove is molded, and then, It is characterized in that the bearing is formed by providing a fitting process of the C-shaped resin ring or the O-shaped resin ring in the ring fitting groove of the bearing outer ring.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to creep (caused by a gap generated when a bearing is incorporated in equipment for rotation, when a bearing outer ring and a bearing box are loosely fitted to each other, and due to a difference in linear expansion coefficient of materials. Figure 10) (In case of inner ring rotation: Phenomenon of outer ring rotating in the opposite direction to inner ring) and spin (In case of inner ring rotation: Phenomenon of outer ring rotating in the same direction as inner ring) It relates to a manufacturing method.

[0002]

2. Description of the Related Art In a conventional creep prevention bearing, a bearing outer ring is inserted into a mold and a resin winding portion is molded by an injection molding machine (FIG. 7).

In this case, the shape of the bearing outer ring groove and the shape of the resin portion, the resin flow due to the difference between the resin temperature and the bearing outer ring temperature, and the shape after solidification become unstable, and it is very difficult to obtain high dimensional accuracy. It was difficult. For that reason, the molded bearing outer ring resin part, once the resin absorbs moisture,
Grinding (Fig. 9) was performed on a lathe to ensure accuracy. As described above, the creep preventing bearing has been put on the market as a product after undergoing several steps from insert molding.

[0004]

However, in the conventional method, the grinding process (FIG. 9) is required to obtain accuracy. Also, in order to mold the resin, the bearing outer ring must be inserted into the mold manually or by machine,
In addition to requiring skill, there is a drawback in that quality control labor and total cost for removing rust and oil of the bearing outer ring are increased.

The present invention has been made in view of such conventional problems, and an object thereof is to provide a method of manufacturing a bearing with a resin ring capable of preventing the creep and spin phenomena. By achieving this object, it is possible to provide a high quality, low cost bearing having an extremely simple and novel structure.

[0006]

[Means for Solving the Problems]

1) Regarding the C-shaped resin ring, the first invention of the present application for achieving the above object is such that a ring fitting groove is engraved at a predetermined position of the bearing outer ring, and the ring fitting groove is fitted in a separate step. A C-shaped resin ring having a matching inner diameter is formed, and then a step of fitting the C-shaped resin ring is provided in the ring fitting groove of the bearing outer ring to form the bearing (claim 1). The first aspect of the invention has a structure in which the C-shaped resin ring is lightly opened left and right in the bearing outer ring groove by hand or by a machine and can be easily assembled and removed (FIG. 3).

This utilizes the elastic deformation of resin. Also, in order not to insert the bearing outer ring into the mold,
Since there is no concern about rust and the mold structure is simple, the cost can be reduced. Further, since the structure of the resin ring is simple, a stable and highly accurate and inexpensive product can be molded. The ring material has a low water absorption rate, a low molding shrinkage rate, a high thermal deformation temperature, a high linear expansion coefficient, and a thermoplastic resin (for example, polyamide-based or polyester-based (PET, PCT, etc.), PBT (polybutylene terephthalate) or the like is used.

2) O-shaped resin ring In a second invention of the present application for achieving the above object, a groove for ring fitting is engraved at a predetermined position of a bearing outer ring, and the ring fitting groove is formed in a separate process. An O-shaped resin ring having an inner diameter that fits in the groove is molded, and then a step of fitting the O-shaped resin ring is provided in the ring fitting groove of the bearing outer ring to form the bearing. 2). The second aspect of the invention has a structure in which the O-shaped resin ring is lightly spread in the bearing outer ring groove by hand or by a machine so that it can be easily assembled and removed (FIG. 4). this is,
This is because it is made of a thermoplastic elastomer (polyamide-based, polyester-based, polyolefin-based, polystyrene-based, etc.) and a silicone resin, and therefore it is resistant to deformation strain and elastic deformation, and easily extends and contracts.

Further, since the bearing outer ring is not inserted into the mold, there is no fear of rusting and the structure of the mold is simple, so that the cost can be reduced. Further, since the structure of the resin ring is simple, a stable and highly accurate and inexpensive product can be molded.

In addition, by using a material having no compression set and a large impact resilience, creep and spin phenomena can be prevented due to the properties of the resin even if the precision of the bearing outer ring groove is kept low.

[0011]

[Function] When a bearing with a resin ring is press-fitted into the bearing box (Fig. 5), at normal temperature, the contact area between the bearing outer diameter surface and the bearing box inner diameter surface is large. The phenomenon does not occur. However, when the temperature rises, a gap is created due to the difference in linear expansion coefficient between the bearing outer ring and the bearing box. However, the resin ring having a larger linear expansion coefficient than that fills the gap and presses the bearing outer ring, so that the creep and spin phenomena can be prevented.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. 1) Regarding C-shaped resin ring First, as shown in FIG. 1 and FIG.
A shaped ring (partially cut) is molded. Then, as shown in FIG. 3, the C-shaped resin ring is incorporated into the groove formed in the bearing outer ring. This resin ring bearing is pressed into the bearing box (Fig. 13).

According to the experiment, even if the shaft is rotated at a high speed (15,000 rpm to 20,000 rpm) at normal temperature (20 ° C.) (FIG. 5), there is no problem in the bearing function and there is no gap between the bearing outer ring and the bearing box. I couldn't see it. However, at high temperature (150
(° C), there was a slight gap between the outer bearing ring and the inner diameter of the bearing box (Fig. 10). This is due to the difference in linear expansion coefficient between the bearing outer ring and the bearing box. Here, even when the shaft was rotated at high speed (15,000 rpm to 20,000 rpm), neither creep nor spin phenomenon was observed. Also, there was no problem in the bearing function.

2) O-shaped resin ring As shown in FIGS. 2 and 8, an O-shaped ring is molded by an injection molding machine. Then, as shown in FIG. 4, the O-shaped resin ring is incorporated into the groove formed in the bearing outer ring.

As shown in FIG. 11, a gap is provided between the O-shaped resin ring and the bearing outer ring groove. This is because, as shown in FIG. 12, when the resin ring bearing is press-fitted into the bearing box, the resin spreads and fills the gap.

According to the experiment, at normal temperature (20 ° C.), even if the shaft is rotated at high speed (15,000 rpm to 20,000 pm) (FIG. 5), there is no problem in the bearing function, and there is no gap between the bearing outer ring and the bearing box. I couldn't see it. However, at high temperature (150
(° C), there was a slight gap between the bearing outer ring and the inner diameter of the bearing box (Fig. 10). This is due to the difference in linear expansion coefficient between the bearing outer ring and the bearing box. Even if the shaft is rotated at high speed (15,000 rpm to 20,000 rpm), the creep,
No spin phenomenon was observed. Also, there was no problem in the bearing function.

[0017]

Since the present invention is manufactured as described above, it has the following effects.

A resin ring is molded by an injection molding machine with a die having a low cost and a simple structure. And the resin ring can be easily installed and removed. For this reason, bearings with low cost and easy quality control are manufactured.

As described above, if the temperature is within the thermal deformation temperature of the resin, it is possible to provide a bearing for preventing creep and spin that does not cause a problem even at high temperatures. Further, by using this bearing in a rotating part such as a motor part and a compressor part where temperature changes drastically, further cost reduction and simplification can be achieved.

[Brief description of drawings]

FIG. 1 is a front view and an AA sectional view of an example C-shaped resin ring molded for a method of the present invention.

2A and 2B are a front view and a BB sectional view of an example O-shaped resin ring molded for the method of the present invention.

FIG. 3 is a perspective view illustrating an assembly of a C-shaped resin ring and a bearing outer ring.

FIG. 4 is a perspective view illustrating an assembly of an O-shaped resin ring and a bearing outer ring.

FIG. 5 is a cross-sectional view illustrating the states of the resin ring bearing and the bearing box at room temperature.

FIG. 6 is a cross-sectional view illustrating the states of the resin ring bearing and the bearing box at high temperature.

FIG. 7 is a schematic process diagram illustrating a conventional method of manufacturing a resin wound bearing.

FIG. 8 is a diagram illustrating a molding process of C-shaped and O-shaped resin rings.

FIG. 9 is a diagram illustrating a secondary finishing process (a lathe grinding process) of a conventional resin wound bearing.

FIG. 10 is a diagram illustrating a creep phenomenon.

FIG. 11 is a diagram illustrating a free state when an O-shaped resin ring is incorporated in the bearing outer ring.

FIG. 12 is a cross-sectional view illustrating a state in which a bearing with an O-shaped resin ring is press-fitted into a bearing box.

FIG. 13 is a diagram illustrating a step of press-fitting a bearing with a resin ring into a bearing box.

Claims (2)

[Claims] 1. A ring fitting groove is engraved at a predetermined position of a bearing outer ring, and a C-shaped resin ring having an inner diameter to be fitted into the ring fitting groove is formed in a separate step, and then the bearing outer ring is formed. The method for manufacturing a bearing with a resin ring, wherein the bearing is formed by providing the step for fitting the C-shaped resin ring in the ring fitting groove. 2. A ring fitting groove is engraved at a predetermined position of the bearing outer ring, and an O-shaped resin ring having an inner diameter that fits in the ring fitting groove is formed in a separate step, and then the bearing outer ring is formed. The method for producing a bearing with a resin ring, wherein the bearing is formed by providing the O-shaped resin ring fitting step in the ring fitting groove.