Compressor with steel and cast iron sliding materials
View Patent ↗A compressor, characterized in that a steel is used as the base material for the other sliding material vane 10 and nitrided, a CrN or DLC film is formed on the surface by PVD treatment, and a Ni—Cr—Mo cast iron is used for the other corresponding sliding material piston 9 . It is possible in such a configuration to suppress the temperature rise by sliding friction of the sliding materials, such as the vane tip region 10 a and the peripheral region of piston 9 that are vigorously slid, relax decomposition of the refrigerant, and suppress corrosion by hydrogen fluoride generated in reaction with water and oxygen, and thus to provide a compressor higher in reliability.
1. A compressor, comprising:
a compressing mechanism unit including:
first and second sliding materials in sliding contact,
the first sliding material including a nitrided steel as a base material;
and a CrN or DLC film formed on a surface of the base material by PVD treatment; and
the second sliding material including a Ni—Cr—Mo cast iron;
wherein the compressor uses a refrigerant containing a hydrofluoroolefin having a carbon-carbon double bond as a base component as its operating refrigerant, and a refrigeration oil miscible with the refrigerant.
2. The compressor according to claim 1 , wherein the operating refrigerant comprises a mixed refrigerant containing a hydrofluoroolefin having a carbon-carbon double bond as a base component and a hydrofluorocarbon having no double bond.
3. The compressor according to claim 2 , wherein:
the hydrofluoroolefin is tetrafluoropropene (HFO1234yf);
the hydrofluorocarbon is one or both of difluoromethane (HFC32) and pentafluoroethane (HFC125); and
the refrigeration oil is a polyvinylether, a polyol ester or a polyalkylene glycol.
4. The compressor according to claim 1 , wherein the refrigeration oil contains no extreme pressure additive.
5. A compressor, comprising:
a compressing mechanism unit comprising: a piston and a vane in a cylinder,
the vane including a nitrided steel as a base material; and
a CrN or DLC film formed on a surface of the base material by PVD treatment; and
the piston material including a Ni—Cr—Mo cast iron;
wherein the compressor uses a refrigerant containing a hydrofluoroolefin having a carbon-carbon double bond as a base component as its operating refrigerant, and a refrigeration oil miscible with the refrigerant.
6. The compressor according to claim 5 , wherein a thickness of the CrN or DLC film formed on a tip region of the vane by PVD treatment is 5 to 15 μm.
7. The compressor according to claim 5 , wherein the film is formed only on a tip region of the vane by PVD treatment.
8. The compressor according to claim 5 , wherein the operating refrigerant comprises a mixed refrigerant containing a hydrofluoroolefin having a carbon-carbon double bond as the base component and a hydrofluorocarbon having no double bond.
9. The compressor according to claim 5 , wherein the refrigeration oil contains no extreme pressure additive.
10. A compressor, comprising:
a compressing mechanism unit having a motor in a tightly sealed container and a shaft driven by the motor installed therein;
the compressing mechanism unit having bearings at both terminal faces of a cylinder, a piston eccentrically rotated by the shaft in the cylinder, and
a vane dividing the cylinder to suction and compression chambers, a tip region of which is in contact with a peripheral surface of the piston under pressure, the vane including a nitrided steel as a base material and a CrN or DLC film formed on a surface of the base material by PVD treatment, and
the piston material including a Ni—Cr—Mo cast iron;
wherein the compressor uses a refrigerant containing a hydrofluoroolefin having a carbon-carbon double bond as a base component as its operating refrigerant, and a refrigeration oil miscible with the refrigerant.
11. The compressor according to claim 10 , wherein a thickness of the CrN or DLC film formed on the tip region of the vane by PVD treatment is 5 to 15 μm.
12. The compressor according to claim 10 , wherein the film is formed only on the tip region of the vane by PVD treatment.
13. The compressor according to claim 10 , wherein the operating refrigerant comprises a mixed refrigerant containing a hydrofluoroolefin having a carbon-carbon double bond as the base component and a hydrofluorocarbon having no double bond.
14. The compressor according to claim 10 , wherein the refrigeration oil contains no extreme pressure additive.