JPH07317779A - Solid lubricant rolling bearing - Google Patents

Abstract

PURPOSE:To eliminate inner distorsion of a shield plate improve corrosion resistance thereof and enable confirmation of presence of solid lubricant films made of low molecular weight PTFE on a bearing by making the shield plate to be installed on the end face of the bearing of an austenite-derived stainless steel, and then performing temper treatment. CONSTITUTION:A bearing has an inner ring 1, an outer ring 2, a rolling body 3, and a shield plate 5. Solid lubricant films la, 2a, 3a made of polytetrafuluoroethyrene each having mean molecular weight not more than 5000 (PTFE of low molecular weight) are formed on the rolling surfaces of the inner and outer rings 1, 2 and the surface of the rolling body 3. An austenite-derived stainless steel is adopted to the shield plate 5. The shield plate 5 installed on an inner diameter surface of an end of the outer ring 2 is subjected to temper treatment. Due to this temper treatment, inner distorsion of the shield plate is eliminated. The temper treatment causes brown color, so that presence of solid lubricant film made of low molecular weight PTFE on the bearing is distinguished.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid lubrication rolling bearing used in an environment where high cleanliness is required in both atmosphere and vacuum.

[0002]

2. Description of the Related Art Recent facilities such as semiconductor manufacturing, hard disk manufacturing, and crystal unit manufacturing not only can be used in a vacuum, but also have functions such as both atmospheric and vacuum use, low dust generation, corrosion resistance, and long life. Rolling bearings are needed. As a rolling bearing having these functions, the present applicant has formed a solid lubricating coating made of polytetrafluoroethylene (hereinafter, referred to as low molecular weight PTFE) having an average molecular weight of 5000 or less on the surface where rolling friction or sliding friction occurs. A solid lubrication rolling bearing has already been proposed (see Japanese Patent Laid-Open No. 5-33813).

By the way, as the material of the rolling bearing used for such an application, stainless steel is often used, and a shield plate is attached to prevent foreign matter from entering from the outside. There are many things. This shield plate is usually manufactured by press-molding austenitic stainless steel, and is caulked and fixed to the end of the bearing.

[0004]

The conventional shield plate is
The press molded product is mounted on the bearing as it is,
If the internal strain remains, the shield plate may be deformed or detached due to the internal strain. In addition, the corrosion resistance of the shield plate may be a concern depending on the use environment.

On the other hand, since the solid lubricating coating made of low molecular weight PTFE is colorless, it is difficult to confirm whether or not the bearing has been coated. Originally, there is no direct close relationship between removing internal strain of the shield plate and improving corrosion resistance, and confirming whether or not the bearing is coated with a solid lubricating coating made of low molecular weight PTFE. Heretofore, there has been provided no means for simultaneously solving these problems.

According to the present invention, whether or not a bearing is provided with a solid lubricating coating made of low molecular weight PTFE while removing internal strain and improving corrosion resistance of a shield plate of a rolling bearing which requires high cleanliness in both atmosphere and vacuum It is an object of the present invention to provide a solid lubrication rolling bearing capable of confirming the above.

[0007]

In order to achieve the above-mentioned object, the present invention provides an inner ring and an outer ring, rolling elements equidistantly arranged via a cage between them, and the inner ring and the outer ring. And a shield plate, and a solid lubricating rolling formed by forming a solid lubricating coating made of polytetrafluoroethylene having an average molecular weight of 5000 or less on the surface of at least rolling friction or sliding friction of the inner and outer rings, rolling elements, and cage In the bearing, the shield plate attached to the end surface of the bearing is made of austenitic stainless steel and is tempered (tempered).

[0008]

The internal strain of the shield plate is removed by constructing the shield plate mounted on the end surface of the rolling bearing from austenitic stainless steel and performing tempering, thereby stabilizing the quality. In addition, the tempering treatment forms an oxide film on the surface of the shield plate to prevent rusting. Further, a shield plate made of austenitic stainless steel was tempered to give a heavy brown color, and this shield plate was colored to determine whether the bearing was coated with a solid lubricating coating made of low molecular weight PTFE. Can be identified.

[0009]

EXAMPLES Examples of the present invention will be described below.

FIG. 1 shows an embodiment in which the present invention is applied to a deep groove ball bearing. This bearing consists of inner ring 1, outer ring 2, inner and outer ring 1
And a plurality of rolling elements 3 interposed between the two, a cage 4 for holding the rolling elements 3 at equal intervals around the circumference, and a shield plate 5 attached to both ends of the outer ring 2. These bearing components are made of stainless steel because they are suitable for use in applications requiring high cleanliness and are used in both atmosphere and vacuum. Then, solid lubricating coatings 1a, 2a, 3a made of polytetrafluoroethylene (low molecular weight PTFE) having an average molecular weight of 5000 or less are formed on the rolling surfaces of the inner and outer races 1, 2 and the surface of the rolling elements 3, respectively. ing. The solid lubricating coatings 1a, 2a, and 3a are prepared by immersing a finished bearing or each component constituting the bearing in a solution in which low-molecular weight PTFE is dispersed in an organic solvent, and then taking it out and transferring it to a constant temperature bath for about 50 minutes. It is formed by holding at 5 ° C. for 5 hours and then naturally cooling at room temperature. As low molecular weight PTFE, Vidax AR, Vidax 1000 (all manufactured by DuPont), Lubron LD-1 (manufactured by Daikin Industries, Ltd.), M
P1200, MP1300 (both manufactured by Mitsui Fluorochemical Co., Ltd.) and the like can be used. Incidentally, the solid lubricating film 1
As a method of forming a, 2a, and 3a, in addition to the above-mentioned dipping method, for example, there is a spray method in which the solution is sprayed and adhered to the film formation surface.

The shield plate 5 is made of austenitic stainless steel (SUS304, SUS303). This austenitic stainless steel plate material is press-molded, and the outer peripheral portion is curved to form a mounting portion 5a in the mounting groove 2b on the inner diameter surface of the end portion of the outer ring 2. The shield plate 5 is tempered in the atmosphere at a high temperature of 350 to 400 ° C. for 2 hours. This tempering treatment is a kind of heat treatment and belongs to tempering treatment. By performing this tempering treatment, the shield plate 5 made of austenitic stainless steel is adjusted to a structure in which toughness is increased, internal residual stress is removed, and an oxide film is formed on the surface. Has rust prevention effect. Further, the tempering treatment causes the shield plate 5 to have a heavy brown color on its surface. Usually, it may be treated at 400 ° C. for 2 hours, but depending on the size, it may have a reddish brown color at 400 ° C. and may impair the appearance. In such a case,
After maintaining at a temperature lower than 400 ° C. to 350 ° C. for about 2 hours and then returning to normal temperature by natural cooling, it is possible to develop a heavy brown color as described above.

It was confirmed by repeated experiments that the shield plate 5 having a uniform color without color unevenness was obtained by performing the tempering treatment under the above-mentioned conditions. Further, the shield plate 5 after the tempering treatment is attached to the outer ring 2 to
It was confirmed by experiments whether there was any deformation, misalignment, or poor roundness of the bearing, but it was confirmed that there was no abnormality.

Although the embodiments of the drawings show the case where the present invention is applied to a deep groove ball bearing, it is obvious that the present invention may be applied to other types of bearings. Further, although the shield plate is mounted on the outer ring side, it may be mounted on the inner ring side.

[0014]

According to the present invention, the internal strain of the shield plate is removed by forming the shield plate mounted on the end portion of the rolling bearing from austenitic stainless steel and subjecting it to tempering. It is possible to stabilize the quality. In addition, the tempering treatment forms an oxide film on the surface of the shield plate to prevent rusting. Further, a shield plate made of austenitic stainless steel was tempered to give a heavy brown color, and this shield plate was colored to determine whether the bearing was coated with a solid lubricating coating made of low molecular weight PTFE. Can be identified. In particular, the coloring due to the tempering treatment is performed directly on the surface of the shield plate as it is colored directly from the base metal, so it does not peel off like coloring with paint and does not discolor, so durability It also has the effect of giving a high-grade appearance as a rolling bearing for this type of application.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing an embodiment in which the present invention is applied to a deep groove ball bearing.

[Explanation of symbols]

 1 Inner ring 2 Outer ring 3 Rolling element 4 Cage 5 Shield plate 1a ・ 2a ・ 3a Solid lubrication film

Claims (1)

[Claims] 1. An inner ring, an outer ring, a rolling element equidistantly arranged between the inner ring and the outer ring via a cage, and a shield plate attached to the ends of the inner ring and the outer ring. In a solid-lubricating rolling bearing in which a solid lubricating coating made of polytetrafluoroethylene having an average molecular weight of 5000 or less is formed on at least the surface where rolling friction or sliding friction occurs, a shield plate mounted on the end surface of the bearing is an austenitic type. Solid lubricated rolling bearings made of stainless steel and tempered.