Hermetic compressor and refrigeration apparatus including the same

Abstract

A hermetic compressor according to the present invention includes: an electric element ( 103 ); a compression element ( 105 ) driven by the electric element ( 103 ); and a sealed container ( 101 ) accommodating the electric element ( 103 ) and the compression element ( 105 ), the sealed container ( 101 ) storing an oil ( 113 ). The compression element ( 105 ) includes: a crank shaft ( 119 ) including a main shaft ( 129 ), an eccentric shaft ( 127 ), and an oil supply mechanism ( 131 ); a cylinder block ( 121 ) including a main bearing ( 137 ) and a cylinder ( 135 ), the main bearing ( 137 ) pivotally supporting the main shaft ( 129 ) of the crank shaft ( 119 ), the cylinder ( 135 ) forming a compression chamber ( 133 ); a piston ( 123 ) configured to move inside the cylinder ( 135 ) in a reciprocating manner; and a connector ( 125 ) connecting the eccentric shaft ( 127 ) and the piston ( 123 ). A first oil groove ( 139 A) extending in a circumferential direction of the cylinder ( 135 ) is provided on at least part of an upper outer peripheral surface of the cylinder ( 135 ).

1 . A hermetic compressor comprising:
 an electric element;   a compression element driven by the electric element; and   a sealed container accommodating the electric element and the compression element, the sealed container storing an oil, wherein   the compression element includes:
 a crank shaft including a main shaft, an eccentric shaft, and an oil supply mechanism; 
 a cylinder block including a main bearing and a cylinder, the main bearing pivotally supporting the main shaft of the crank shaft, the cylinder forming a compression chamber; 
 a piston configured to move inside the cylinder in a reciprocating manner; and 
 a connector connecting the eccentric shaft and the piston, and 
   a first oil groove extending in a circumferential direction of the cylinder is provided on at least part of an upper outer peripheral surface of the cylinder.   
     
     
         2 . The hermetic compressor according to  claim 1 , wherein side walls forming the first oil groove are formed such that a height of the side walls gradually increases from a bottom dead center side to a top dead center side of the cylinder. 
     
     
         3 . The hermetic compressor according to  claim 1 , wherein
 a second oil groove extending in a direction of a central axis of the cylinder is further provided on at least part of the upper outer peripheral surface of the cylinder, the second oil groove being formed such that a bottom thereof slopes downward from a bottom dead center side to a top dead center side of the cylinder, the second oil groove being in communication with the first oil groove.   
     
     
         4 . The hermetic compressor according to  claim 1 , wherein
 the eccentric shaft of the crank shaft is provided with a first oil spreading mechanism configured to spread the oil to the first oil groove and a second oil spreading mechanism configured to spread the oil to a gap formed between the piston and the cylinder.   
     
     
         5 . The hermetic compressor according to  claim 1 , wherein
 a radiation fin is provided on at least part of a lower outer peripheral surface of the cylinder.   
     
     
         6 . The hermetic compressor according to  claim 1 , wherein
 the electric element includes a stator fixed to the cylinder block and a rotor fixed to the crank shaft, and   an air-blowing fin is provided on an end portion of the rotor at the cylinder block side.   
     
     
         7 . The hermetic compressor according to  claim 1 , wherein
 the compression element includes:
 a discharge pipe, through which a refrigerant compressed in the compression chamber is discharged; and 
 a discharge chamber provided on a non-end portion of the discharge pipe. 
   
     
     
         8 . The hermetic compressor according to  claim 1 , wherein
 the electric element is configured to be driven by an inverter at multiple operating frequencies.   
     
     
         9 . A refrigeration apparatus comprising the hermetic compressor according to  claim 1 .