Motor operated compressor

Abstract

A motor operated compressor includes an orbiting scroll that defines a compression chamber together with a fixed scroll. The compressor includes a main frame disposed around and supporting the orbiting scroll. The main frame defines a back-pressure chamber together with the orbiting scroll. The compressor includes a groove disposed in one of the orbiting scroll and the main frame. A first sealing member is inserted into the groove. A second sealing member is inserted into the groove to elastically press the first sealing member into close contact with the orbiting scroll or the main frame. A radial distance (a) between an outer wall of the groove and the first sealing member is 6 to 8% (0.06≤a/W≤0.08) of a difference (W) between an outer radius (OR) and an inner radius (IR) of the first sealing member (W=OR−IR).

What is claimed is: 
     
         1 . A motor operated compressor, comprising:
 an orbiting scroll configured to define a compression chamber together with a fixed scroll;   a main frame disposed opposite to the fixed scroll and around the orbiting scroll, the main frame being configured to support the orbiting scroll and define a back-pressure chamber together with the orbiting scroll;   a groove disposed in one of the orbiting scroll and the main frame, the groove facing the other one of the orbiting scroll and the main frame, the groove having a closed curved shape around the back-pressure chamber;   a first sealing member inserted into the groove and configured to seal the back-pressure chamber; and   a second sealing member inserted into the groove and configured to elastically press the first sealing member into close contact with the orbiting scroll or the main frame,   wherein a distance (a) in a radial direction of the first sealing member and between an outer wall of the groove and the first sealing member is 6 to 8% (0.06≤a/W≤0.08) of a difference (W) between an outer radius (OR) and an inner radius (IR) of the first sealing member (W=OR−IR).   
     
     
         2 . The motor operated compressor of  claim 1 , wherein the groove comprises:
 a first groove recessed in a direction away from one of the orbiting scroll and the main frame, the first groove being disposed on one surface of the other one of the orbiting scroll and the main frame, the first groove having a bottom surface spaced apart from the one surface; and   a second groove recessed in the same direction as the recess direction of the first groove, the second groove being disposed on the bottom surface of the first groove and having an outer diameter different from that of the first groove, and   wherein the first sealing member is inserted into the first groove, and   the second sealing member is inserted into the second groove.   
     
     
         3 . The motor operated compressor of  claim 2 , wherein an outer diameter of the first groove is greater than that of the second groove. 
     
     
         4 . The motor operated compressor of  claim 2 , wherein an inner diameter of the first groove is the same as that of the second groove. 
     
     
         5 . The motor operated compressor of  claim 1 , wherein a fluid subject to compression in the motor operated compressor comprises carbon dioxide. 
     
     
         6 . The motor operated compressor of  claim 1 , wherein the first sealing member is made of engineering plastic. 
     
     
         7 . The motor operated compressor of  claim 6 , wherein the first sealing member is made of polyetherether ketone (PEEK). 
     
     
         8 . The motor operated compressor of  claim 6 , wherein the first sealing member is made of polytetrafluoroethylene (PTFE). 
     
     
         9 . The motor operated compressor of  claim 1 , wherein the first sealing member has a closed curved annular shape. 
     
     
         10 . The motor operated compressor of  claim 1 , wherein the second sealing member is made of rubber. 
     
     
         11 . The motor operated compressor of  claim 1 , wherein the second sealing member is made of fluorine rubber. 
     
     
         12 . The motor operated compressor of  claim 1 , wherein the second sealing member is made of fluorine rubber corresponding to a material symbol FKM of the ASTM 1418 standard among fluorine rubbers. 
     
     
         13 . The motor operated compressor of  claim 1 , wherein the second sealing member has a Brinell hardness (HB) of 70 to 100.