Refrigerant scroll compressor for motor vehicle air conditioning systems

Abstract

A refrigerant scroll compressor for a motor vehicle air conditioning system having a fixed scroll, an orbiting scroll engaging with the fixed scroll, wherein the fixed scroll and the orbiting scroll cooperate to compress a refrigerant gas. An intermediate pressure chamber is disposed adjacent the orbiting scroll, an oil return duct provides fluid communication between the intermediate pressure chamber and a high pressure area of the refrigerant scroll compressor, and at least one intermediate pressure duct is formed in one of the orbiting scroll and fixed scroll and is in fluid communication with the intermediate pressure chamber.

What is claimed is: 
     
         1 . A refrigerant scroll compressor for a motor vehicle air conditioning system comprising:
 a fixed scroll;   an orbiting scroll engaging with the fixed scroll, wherein the fixed scroll and the orbiting scroll cooperate to compress a refrigerant gas;   an intermediate pressure chamber disposed adjacent the orbiting scroll;   an oil return duct providing fluid communication between the intermediate pressure chamber and a high pressure area of the refrigerant scroll compressor; and   at least one intermediate pressure duct formed in one of the orbiting scroll and the fixed scroll and in fluid communication with the intermediate pressure chamber.   
     
     
         2 . The refrigerant scroll compressor of  claim 1 , wherein the fixed scroll and the orbiting scroll cooperate to define a plurality of cavities intermediate the fixed scroll and the orbiting scroll, wherein the at least one intermediate pressure duct is in fluid communication with at least one of the plurality of cavities and is configured to facilitate a flow of the refrigerant gas between the at least one of the plurality of cavities and the intermediate pressure chamber. 
     
     
         3 . refrigerant scroll compressor of  claim 1 , further comprising an oil extraction duct in fluid communication with the intermediate pressure chamber. 
     
     
         4 . The refrigerant scroll compressor of  claim 3 , further comprising an expansion device in fluid communication with the oil extraction duct and disposed downstream of the intermediate pressure chamber in respect of the flow of an oil in the refrigerant scroll compressor, the expansion device configured to decompress the oil. 
     
     
         5 . The refrigerant scroll compressor of  claim 1 , wherein the at least one intermediate pressure duct is formed in the orbiting scroll. 
     
     
         6 . The refrigerant scroll compressor of  claim 5 , wherein the at least one intermediate pressure duct is an intermediate pressure bore. 
     
     
         7 . The refrigerant scroll compressor of  claim 1 , wherein the at least one intermediate pressure duct is formed in the fixed scroll. 
     
     
         8 . The refrigerant scroll compressor of  claim 1 , further comprising an expansion device in fluid communication with the oil return duct and disposed upsteam of the intermediate pressure chamber in respect of a flow of an oil in the refrigerant scroll compressor, the expansion device configured to decompress the oil. 
     
     
         9 . The refrigerant scroll compressor of  claim 8 , wherein a ratio of a cross-section of the at least one intermediate pressure duct to a cross-section of the expansion device is between five and twenty. 
     
     
         10 . The refrigerant scroll compressor of  claim 9 , wherein the ratio of the cross-section of the at least one intermediate pressure duct to the cross-section of the expansion device is ten. 
     
     
         11 . The refrigerant scroll compressor of  claim 1 , further comprising a gasket disposed adjacent the orbiting scroll configured to support the orbiting scroll and seal the orbiting scroll with respect to a stationary housing. 
     
     
         12 . A refrigerant scroll compressor for a motor vehicle air conditioning system comprising:
 a fixed scroll;   an orbiting scroll engaging with the fixed scroll and cooperating to define a plurality of cavities intermediate the fixed scroll and the orbiting scroll, wherein the fixed scroll and the orbiting scroll cooperate to compress a refrigerant gas;   an intermediate pressure chamber disposed adjacent the orbiting scroll;   an oil return duct at least partially formed in the fixed scroll and providing fluid communication between a high pressure area and a suction area of the refrigerant scroll compressor; and   at least one intermediate pressure duct formed in one of the orbiting scroll and the fixed scroll and in fluid communication with the intermediate pressure chamber, wherein the at least one intermediate pressure duct is in fluid communication with at least one of the plurality of cavities and is configured to facilitate a flow of the refrigerant gas between the at least one of the plurality of cavities and the intermediate pressure chamber.   
     
     
         13 . The refrigerant scroll compressor of  claim 12 , wherein the oil return duct is in fluid communication with the intermediate pressure chamber. 
     
     
         14 . The refrigerant scroll compressor of  claim 13 , further comprising an oil extraction duct in fluid communication with the intermediate pressure chamber. 
     
     
         15 . The refrigerant scroll compressor of  claim 14 , further comprising a first expansion device in fluid communication with the oil return duct and disposed upsteam of the intermediate pressure chamber in respect of a flow of an oil in the refrigerant scroll compressor and a second expansion device in fluid communication with the oil extraction duct and disposed downstream of the intermediate pressure chamber in respect of the flow of the oil through the refrigerant scroll compressor, the first expansion device and the second expansion device are configured to decompress the oil. 
     
     
         16 . The refrigerant scroll compressor of  claim 15 , wherein a ratio of a cross-section of the at least one intermediate pressure duct to a cross-section of the first expansion device is between five and twenty. 
     
     
         17 . The refrigerant scroll compressor of  claim 16 , wherein the ratio of the cross-section of the at least one intermediate pressure duct to the cross-section of the first expansion device is ten.