JP3358752B2 - Solid lubricated rolling bearing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to a solid lubricated rolling bearing used in an environment where lubricating oil or grease cannot be used, such as under radiation.

[0002]

2. Description of the Related Art Conventionally, there are, for example, the following three methods of lubricating rolling bearings of various devices operating in an environment where lubricating oil or grease cannot be used, such as at high temperatures, in vacuum, at extremely low temperatures, or under radiation. (1) A method of forming a thin lubricating film such as molybdenum disulfide (MoS ₂ ) or silver (Ag) on all or a part of sliding surfaces of an inner ring, an outer ring, a cage, and a rolling element by sputtering. Examples are described in JP-A-55-57717, JP-A-58-113629 and JP-A-61-55410.
Issue. (2) A cage is formed using plastic or a polymer composite material obtained by adding a solid lubricant to plastic,
A method in which a cage material is transferred to an inner ring and an outer ring via a rolling element and a rolling element by friction between a rolling element and a cage to form a thin lubricating film. As a typical example, a polytetrafluoroethylene resin ( Lulon E (NTN, PTFE) formed by adding glass fiber and MoS ₂ to PTFE
Lulon (brand name) or Duroid (Bard, USA)
There is a retainer formed by the name of “en company”. In addition, there is a cage formed of polyphenylene sulfide (PPS) -based composite resin (manufactured by NSK). Also, as disclosed in Japanese Patent Application Laid-Open No. 4-102718, PTFE
There are a MoS ₂ and aromatic polyamide fibers polyetheretherketone was added (PEEK) cage made of a resin. As a polymer-based composite material other than PTFE and PEEK, there is a cage formed of polyimide having thermally stable characteristics (for example, Vespel SP-3 (trade name of DuPont, USA)). (3) A cage made of a sintered alloy obtained by adding a solid lubricant such as MoS ₂ or tungsten disulfide (WS ₂ ) to a metal or an alloy is used, and the cage material is rolled by friction between the rolling elements and the cage. This is a method of forming a thin lubricating film by transferring to a inner ring and an outer ring via a moving body and a rolling element, and typical examples thereof are disclosed in JP-A-62-151539 and JP-A-63-246507.

[0003]

However, in the method of forming a thin lubricating film in advance as described in (1) above, if the film is worn by friction, the lubricating effect is lost and the metal of the base material is exposed. As a result, image sticking occurs, so that the life is generally short. In the method (2) using a polymer-based composite material, the manufacture of the cage is easy, but the continuous use temperature is about 250.
C. or lower, and cannot be used under extremely high temperature conditions. Further, in the cage using a sintered metal as in (3), there is a problem that the material is brittle, so that the machinability is poor, the material is broken when used, the friction noise is large, and the wear in the atmosphere is extremely large. As described above, the conventional solid lubricated rolling bearing has problems such as a short life, low heat resistance, and poor workability of the cage. Therefore, an object of the present invention is to provide a solid lubricated rolling bearing in which a cage can be easily manufactured and has a long life at a high temperature.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides an inner ring, an outer ring, a rolling element housed between raceways of the inner ring and the outer ring, and guides and holds the rolling element. A solid lubricated rolling bearing made of a composite material containing an organic resin, a solid lubricant such as graphite or molybdenum disulfide, and a reinforcing agent such as carbon fiber or glass fiber. In the composite material of the cage, the solid lubricant
Of 5 to 15 wt% graphite and 2 to 8 wt% nitriding
Boron, and the reinforcing agent is 5 to 15 wt% carbon fiber.
Fiber, and the remainder is polybenzimid of the organic resin.
It is configured as dazole resin . Further, the retainer
The composite material of the present invention is obtained by adding the solid lubricant to 3 to 8% by weight of disulfide.
Molybdenum and 3 to 6 wt% boron nitride, strengthening
The agent is 10-15 wt% glass fiber and the rest is
As the organic resin polybenzimidazole resin
Good.

[0005]

According to the above-mentioned means, polybenzimidazole (P
BI) resin has a high glass transition point of about 427 ° C, a high heat distortion temperature of 435 ° C, and retains its physical properties even at an extremely low temperature of -200 ° C. It has high heat resistance, toughness, and excellent wear resistance. Therefore, it can be used without deformation in a high temperature atmosphere or in a vacuum. Also, by adding a layered solid lubricant such as graphite, molybdenum disulfide or boron nitride to the PBI resin, the slidability is improved, the transfer is easy, and the lubricity with the mating surface is improved. ,
The mechanical strength is improved by filling with a reinforcing agent such as carbon fiber.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of a solid lubricated rolling bearing of the present invention. In the figure, 1 is an inner ring made of stainless steel SUS440C, 2 is an outer ring made of the same material as the inner ring 1, 3 is a raceway groove, 4 is a rolling element, 5 is a retainer, and 6 is a thickness of a surface of the raceway groove 3 by sputtering. This is a sputtered film coated with 0.5 μm of molybdenum disulfide. The retainer 5 was formed by extruding a material of the type shown in Table 1 into a round bar having a diameter of 20 mm. Thereafter, the shape was finished as shown in the figure by machining.

[0007]

[Table 1]

The cages No. 1 and No. 2 are made of 100% polybenzimidazole (PBI) resin (trade name: Cerazole U-6, manufactured by Hoechst Celanese, USA).
In No. 0), No. 2 is obtained by coating the surfaces of the raceway grooves 3 and the rolling elements 4 with molybdenum disulfide by sputtering. The cages No. 3 to No. 6 are composite materials obtained by mixing carbon fiber as a reinforcing agent and graphite as a solid lubricant in a PBI resin, of which No. 3 is manufactured by Hoechst Celanese Co. , USA under the trade name CERAZOL TL-
60. The compounding ratio is% by weight (wt%). No7
The cages of No. 8 and No. 8 are those in which molybdenum disulfide is used as a solid lubricant and glass fiber is used as a reinforcing agent. In No. 5, a sputtered film of molybdenum disulfide having a thickness of 0.5 μm was formed on the surface of the raceway groove 3 of the bearing by sputtering. This cage was assembled into a ball bearing of frame number # 608. In addition, what produced the same cage as an Example using the following conventional resins as a comparative example was used. MoS to PEEK-based polytetrafluoroethylene (PTFE) resin
₂ and aromatic polyamide fiber and polyetheretherketone (PEEK) resin. PPS-based polyphenylene sulphite (PPS) -based composite resin (N
SK). Next, endurance tests were performed on the bearings of these examples and comparative examples under the following conditions, and the bearing life was measured. Atmospheric pressure 1 × 10 ⁻⁶ Torr Atmospheric temperature 300 ° C., 350 ° C. Thrust load 2.0 kgf Radial load 0.2 kgf Rotation speed 1200 rpm The results of the durability test are shown in Table 2.

[0009]

[Table 2]

The rolling bearings No. 1 to No. 8 of the present invention exhibited a longer life than the comparative example at 300 ° C. and 350 ° C. in a high temperature and vacuum. As described above, the rolling bearing of the present invention is a cerazole composite of molybdenum disulfide and polybenzimidazole resin coated on the rolling contact surface as a solid lubricant, or a polybenzoimidazole resin cerazole resin filled with carbon fiber, graphite and boron nitride. As the material retainer is used in combination with the lubricant, molybdenum disulfide coated on the rolling contact surface functions for lubrication in the initial rotation of the rolling bearing, and this film disappears due to wear over time. Then, the contact film between the rolling element 4 and the retainer 5 continues to form the transfer film 7 from the retainer itself on the surface of the rolling element and further on the raceway surface by an appropriate amount. Therefore, a long life can be ensured in a vacuum. That is, compared to a conventional rolling bearing using a solid lubricant, the rolling bearing has a long life, is maintenance-free for a long period of time, and can provide a rolling bearing with low friction noise. In addition,
In the present embodiment, the retainer is manufactured by machining from an extruded product. However, if a mold for the retainer is formed, the retainer can be formed by compression molding or injection molding. In this embodiment, the deep groove rolling bearing is used. However, the present invention is not limited to this, and it is apparent that the cage can be sufficiently applied to an angular bearing having a crown shape or a cylindrical roller bearing having a hollow shape.

[0011]

According to the present invention as described above, according to the present invention, since using a high heat resistance polybenzimidazole resin material of the cage, it can be used in a high temperature atmosphere, also a solid lubricant to the resin since addition, the effect of high have fabrication process of improved and mechanical strength slidability obtain easy solid lubricating rolling bearings.

[Brief description of the drawings]

FIG. 1 is a sectional view of a rolling bearing showing an embodiment of the present invention.

FIG. 2 is a perspective view of the retainer in FIG.

[Explanation of symbols]

 1: inner ring 2: outer ring 3: raceway groove 4: rolling element 5: retainer 6: sputtered film

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F16C 19/00-19/56 F16C 33/30-33/66

Claims (2)

(57) [Claims] An inner ring, an outer ring, a rolling element housed between raceways of the inner ring and the outer ring, and a retainer for guiding and retaining the rolling element, wherein the retainer is made of an organic resin. In a solid lubricated rolling bearing made of a composite material in which a solid lubricant such as graphite or molybdenum disulfide and a reinforcing agent such as carbon fiber or glass fiber are blended, the composite material of the retainer includes the solid lubricant. 5-15w
t% graphite and 2-8 wt% boron nitride,
5 to 15 wt% of carbon fiber,
And the remainder is a polybenzimidazole tree of the organic resin.
A solid lubricated rolling bearing characterized by using grease . 2. An inner ring, an outer ring, and a rail between the inner ring and the outer ring.
Rolling elements housed between path grooves and guide and hold the rolling elements
A retainer, which comprises: an organic resin;
Solid lubricants such as graphite or molybdenum disulfide
And carbon fiber or glass fiber
Solid lubricated rolling shaft made of composite material containing reinforcing agent
In receiving The composite material of the retainer contains the solid lubricant in an amount of 3 to 8 wt.
% Molybdenum disulfide and 3-6 wt% boron nitride
And the reinforcing agent is 10 to 15 wt% glass fiber.
And the remainder is polybenzimidazole of the organic resin.
A solid lubricated rolling bearing made of resin.