Rotary compressor

Abstract

A rotary compressor including a case defining an external appearance of the compressor. A compressing device is arranged inside the case, and a lower cap is fixed to a lower end of the case. The rotary compressor further includes a weld zone to fix the compressing device and lower cap to each other.

1 . A rotary compressor comprising:
 a case defining an external appearance of the compressor;   a compressing device arranged inside the case;   a lower cap fixed to a lower end of the case; and   a weld zone to fix the compressing device and lower cap to each other.   
     
     
         2 . The compressor according to  claim 1 , wherein the weld zone is formed by at least one reinforcing protrusion extending from the compressing device to the lower cap by a predetermined length. 
     
     
         3 . The compressor according to  claim 1 , wherein the weld zone is formed by at least one supporting protrusion protruding from the lower cap to the compressing device by a predetermined length. 
     
     
         4 . The compressor according to  claim 2 , wherein the compressing device includes a cylinder defining a compression chamber for compression of refrigerant gas, and a lower bearing to support the cylinder from the lower side of the cylinder, and wherein the weld zone is formed in a boundary region between the reinforcing protrusion axially provided at the lower bearing and a through-hole perforated in the lower cap. 
     
     
         5 . The compressor according to  claim 3 , wherein the compressing device includes a cylinder defining a compression chamber for compression of refrigerant gas, and a lower bearing to support the cylinder from the lower side of the cylinder, and
 wherein the weld zone is formed in a boundary region between a through-hole perforated in the supporting protrusion and the lower bearing.   
     
     
         6 . The compressor according to  claim 2 , wherein the reinforcing protrusion is provided at a peripheral position of a lower bearing to come into close contact with a bottom surface of the lower cap when the lower cap is fixed to the case. 
     
     
         7 . The compressor according to  claim 3 , wherein the supporting protrusion is provided at a peripheral position of the lower cap to come into close contact with a lower bearing when the lower cap is fixed to the case. 
     
     
         8 . The compressor according to  claim 4  or  5 , wherein the compressing device further includes an upper bearing to support the cylinder from the upper side of the cylinder. 
     
     
         9 . The compressor according to  claim 8 , further comprising:
 a stator fixed to the case;   a rotor rotatably supported inside the stator; and   a rotating shaft press-fitted in the rotor.   
     
     
         10 . A rotary compressor comprising:
 a case;   a cylinder arranged inside the case;   a lower bearing closely coupled to a lower end of the cylinder; and   a lower cap fixedly welded to the lower bearing for fixing the cylinder in an axial direction.   
     
     
         11 . The compressor according to  claim 10 , wherein at least one protrusion is provided between the lower bearing and the lower cap, to fixedly weld the lower bearing to the lower cap. 
     
     
         12 . The compressor according to  claim 10 , wherein the protrusion is integrally formed with any one of the lower bearing and the lower cap.