초록 ▼

The rolling bearing of the invention to be incorporated in the compressor for fuel cell system comprises a fluorine-based grease containing a fluororesin and a fluorine-based oil, a urea grease containing a urea compound and a synthetic oil or a lithium complex grease containing a lithium complex an

The rolling bearing of the invention to be incorporated in the compressor for fuel cell system comprises a fluorine-based grease containing a fluororesin and a fluorine-based oil, a urea grease containing a urea compound and a synthetic oil or a lithium complex grease containing a lithium complex and a synthetic oil encapsulated therein. In this arrangement, the grease deterioration of the rolling bearing incorporated in the compressor for force-feeding various fluids between machines can be prevented, making it possible to provide a fuel cell system which can maintain stable operation over an extended period of time.

대표청구항 ▼

The invention claimed is: 1. A rolling bearing in combination with a fuel cell system, said rolling bearing having a fluorine-based grease containing a fluororesin and a fluorine-based oil, wherein the kinetic viscosity of the fluorine-based oil at 40째 C. is from 20 mm2/s to 400 mm2/s, wherein ther

The invention claimed is: 1. A rolling bearing in combination with a fuel cell system, said rolling bearing having a fluorine-based grease containing a fluororesin and a fluorine-based oil, wherein the kinetic viscosity of the fluorine-based oil at 40째 C. is from 20 mm2/s to 400 mm2/s, wherein there is encapsulated a grease, other than the fluorine-based grease, having a vapor pressure of not higher than 1.3횞10-1 Pa at 25째 C. as a base oil, and wherein the fuel cell system comprises at least a stack of fuel cells and a compressor for transporting various fluids at the compressor. 2. The rolling bearing as defined in claim 1, wherein the fluorine-based grease is a grease composition comprising a perfluoroalkylether as a base oil, a polytetrafluoroethylene as a thickening agent and at least one of a magnesium compound and a vapor phase inhibitor as a rust preventive. 3. The rolling bearing as defined in claim 2, wherein the content of the magnesium compound in the grease composition is from 0.5 to 3.0% by weight based on the total amount of the grease. 4. The rolling bearing as defined in claim 2, wherein the content of the vapor phase inhibitor in the grease composition is from 0.05 to 1.0% by weight based on the total amount of the grease. 5. The rolling bearing as defined in claim 1, wherein the fluorine-based grease is a grease composition comprising a fluorine-based thickening agent and a fluorine-based surface active agent incorporated in a fluorine-based lubricant. 6. The rolling bearing as defined in claim 5, wherein the grease composition comprises a perfluoropolyether oil as a base oil and a polytetrafluoroethylene as a thickening agent and the fluorine-based surface active agent contains carbon atoms and fluorine atoms in its molecule at a ratio of 1:2 to 2:1 and is incorporated in an amount of from 0.2 to 10% by weight based on the total amount of the grease. 7. The rolling bearing as defined in claim 5, which is used in an atmosphere having an acidic material present therein. 8. The rolling bearing as defined in claim 1, wherein the fluorine-based grease is a fluorine-based grease comprising a fluorine-based oil as a base oil and a fluororesin as a thickening agent and a mixture of the fluorine-based grease and the grease other than the fluorine-based grease is encapsulated therein. 9. The rolling bearing as defined in claim 8, wherein the grease other than the fluorine-based grease in the mixed grease is at least one of a metal complex soap-based grease and a urea-based grease, the mixing ratio (by weight) of at least one of the metal complex soap-based grease and the urea-based grease to the fluorine-based grease is from 30 to 70:80 to 20 and the thickening agent is incorporated in a total amount of from 15 to 35% by weight based on the total amount of the mixed grease. 10. The rolling bearing as defined in claim 8, wherein the kinetic viscosity of the grease, other than the fluorine-based grease, at 40째 C. is from 10 mm2/s to 400 mm2/s. 11. The rolling bearing as defined in claim 8, wherein the mixed grease comprises additives incorporated therein in an amount of not greater than 20% by weight based on the total amount of the mixed grease. 12. The rolling bearing as defined in claim 1, wherein the grease comprises at least one selected from the group consisting of benzotriazole or derivative thereof, indazole or derivative thereof, benzothiazole or derivative thereof, benzoxazole or derivative thereof, benzimidazole or derivative thereof and thiadiazole or derivative thereof and at least one selected from the group consisting of metal dithiophosphate and metal dithiocarbamate incorporated therein in an amount of from 0.2 to 2% by weight and from 1 to 10% by weight based on the total amount of the grease, respectively. 13. The rolling bearing as defined in claim 1, wherein the grease comprises a base oil and a thickening agent incorporated therein and comprises at least one selected from the group consisting of basic alkylamine compound, organic metal salt and metal salt of organic acid incorporated therein in an amount of from 0.1 to 10% by weight based on the total amount of the grease. 14. The rolling bearing as defined in claim 13, which is used in an atmosphere having an acidic material present therein. 15. The rolling bearing as defined in claim 1, wherein a plurality of rolling elements are rollably retained interposed between the inner ring and the outer ring. 16. The rolling bearing as defined in claim 1, wherein a plurality of rolling elements are rollably retained between the inner ring and the outer ring with a retainer provided interposed therebetween. 17. The rolling bearing as defined in claim 1, wherein is provided with a seal or shield. 18. The rolling bearing for fuel cell as defined in claim 1, wherein the fuel cell system comprises at least a fuel tank, a fuel evaporator, a modifying device, a CO remover, a stack of fuel cells and a compressor for transporting various fluids. 19. The rolling bearing for fuel cell as defined in claim 1, which is adapted to be incorporated in an impeller type compressor, a scroll type compressor, a swash plate compressor or a screw type compressor. 20. A compressor for fuel cell system provided with a rolling bearing for fuel cell as defined in claim 1. 21. A fuel cell system comprising a compressor as defined in claim 20 as a compressor for transporting various fluids. 22. The fuel cell system as defined in claim 21, which is provided with at least a stack of fuel cells. 23. The fuel cell system as defined in claim 22, which is further provided with at least a fuel tank, a fuel evaporator, a modifier and a CO remover. 24. The fuel cell system as defined in claim 21, which is adapted for driving automobile.