Rotary compressor and refrigeration cycle apparatus

Abstract

A rotary compressor and a refrigeration cycle apparatus are provided that: can reliably reduce pressure pulsation and vibration in an intermediate pipe connecting a discharge side of a low-stage compression mechanism and a suction side of a high-stage compression mechanism; and can downsize the apparatus including a muffler. A rotary compressor includes: a first cylinder having a first compression chamber that compresses introduced low-pressure refrigerant gas to medium pressure and discharges the compressed refrigerant gas; a second cylinder having a second compression chamber that compresses introduced medium-pressure refrigerant gas; an upstream intermediate pipe guiding the medium-pressure refrigerant gas, discharged from the first compression chamber, to an outside of the sealed container; and an external muffler connected to the upstream intermediate pipe. Relationship between outlet area S1 of the upstream intermediate pipe and flow path cross-sectional area S2 of the external muffler is 0.01≤(S1÷S2)≤0.04.

1 . A rotary compressor comprising:
 a sealed container including a center line extending in an up-down direction;   an electric motor unit provided within the sealed container;   a crankshaft including a low-pressure side eccentric portion and a high-pressure side eccentric portion, and configured to be rotationally driven by the electric motor unit, the low-pressure side eccentric portion being eccentric from a rotation center line, the high-pressure side eccentric portion being provided below the low-pressure side eccentric portion and being eccentric from the rotation center line;   a compression mechanism unit including a low-pressure side cylinder and a high-pressure side cylinder, the low-pressure side cylinder having a low-pressure side compression chamber configured to compress introduced low-pressure refrigerant gas to medium pressure and discharge the compressed refrigerant gas by power of the low-pressure side eccentric portion, the high-pressure side cylinder including a high-pressure side compression chamber configured to compress introduced medium-pressure refrigerant gas by power of the high-pressure side eccentric portion;   an upstream intermediate pipe configured to guide the medium-pressure refrigerant gas, discharged from the low-pressure side compression chamber, to an outside of the sealed container;   a muffler connected to the upstream intermediate pipe; and   a downstream intermediate pipe configured to guide the medium-pressure refrigerant gas, discharged from the muffler, to the high-pressure side compression chamber inside the sealed container,   wherein a relationship between outlet area S1 of the upstream intermediate pipe and flow path cross-sectional area S2 of the muffler is   
       
         
           
             
               0.01 
               ≤ 
               
                 ( 
                 
                   S 
                   ⁢ 
                   
                     1 
                     ÷ 
                     S 
                   
                   ⁢ 
                   2 
                 
                 ) 
               
               ≤ 
               
                 
                   0 
                   . 
                   0 
                 
                 ⁢ 
                 
                   4 
                   . 
                 
               
             
           
         
       
     
     
         2 . The rotary compressor according to  claim 1 , wherein
 the muffler is provided next to the sealed container and has an elongated shape with a center line extending in the up-down direction, and   a top portion of the muffler is lower than a top portion of the sealed container.   
     
     
         3 . The rotary compressor according to  claim 1 , wherein a length of the muffler in the up-down direction is 1.5 times or more an inner diameter of the muffler. 
     
     
         4 . The rotary compressor according to  claim 1 , further comprising a fixing device configured to fix the muffler to the sealed container. 
     
     
         5 . The rotary compressor according to  claim 1 , further comprising:
 an accumulator; and   an outlet pipe configured to guide the low-pressure refrigerant gas from the accumulator to the low-pressure side compression chamber inside the sealed container,   wherein the muffler is tangent to or accommodated inside an imaginary circle, the imaginary circle being centered on the center line of the sealed container, encompassing the accumulator, and being circumscribed to the accumulator.   
     
     
         6 . A refrigeration cycle apparatus comprising:
 the rotary compressor according to  claim 1 ;   a heat radiator;   an expansion device;   a heat absorber; and   a refrigerant pipe that connects the rotary compressor, the heat radiator, the expansion device, and the heat absorber, and configured to allow refrigerant to circulate.   
     
     
         7 . The rotary compressor according to  claim 2 , wherein a length of the muffler in the up-down direction is 1.5 times or more an inner diameter of the muffler. 
     
     
         8 . The rotary compressor according to  claim 2 , further comprising a fixing device configured to fix the muffler to the sealed container. 
     
     
         9 . The rotary compressor according to  claim 3 , further comprising a fixing device configured to fix the muffler to the sealed container. 
     
     
         10 . The rotary compressor according to  claim 2 , further comprising:
 an accumulator; and   an outlet pipe configured to guide the low-pressure refrigerant gas from the accumulator to the low-pressure side compression chamber inside the sealed container,   wherein the muffler is tangent to or accommodated inside an imaginary circle, the imaginary circle being centered on the center line of the sealed container, encompassing the accumulator, and being circumscribed to the accumulator.   
     
     
         11 . The rotary compressor according to  claim 3 , further comprising:
 an accumulator; and   an outlet pipe configured to guide the low-pressure refrigerant gas from the accumulator to the low-pressure side compression chamber inside the sealed container,   wherein the muffler is tangent to or accommodated inside an imaginary circle, the imaginary circle being centered on the center line of the sealed container, encompassing the accumulator, and being circumscribed to the accumulator.   
     
     
         12 . The rotary compressor according to  claim 4 , further comprising:
 an accumulator; and   an outlet pipe configured to guide the low-pressure refrigerant gas from the accumulator to the low-pressure side compression chamber inside the sealed container,   wherein the muffler is tangent to or accommodated inside an imaginary circle, the imaginary circle being centered on the center line of the sealed container, encompassing the accumulator, and being circumscribed to the accumulator.   
     
     
         13 . A refrigeration cycle apparatus comprising:
 the rotary compressor according to  claim 2 ;   a heat radiator;   an expansion device;   a heat absorber; and   a refrigerant pipe that connects the rotary compressor, the heat radiator, the expansion device, and the heat absorber, and configured to allow refrigerant to circulate.   
     
     
         14 . A refrigeration cycle apparatus comprising:
 the rotary compressor according to  claim 3 ;   a heat radiator;   an expansion device;   a heat absorber; and   a refrigerant pipe that connects the rotary compressor, the heat radiator, the expansion device, and the heat absorber, and configured to allow refrigerant to circulate.   
     
     
         15 . A refrigeration cycle apparatus comprising:
 the rotary compressor according to  claim 4 ;   a heat radiator;   an expansion device;   a heat absorber; and   a refrigerant pipe that connects the rotary compressor, the heat radiator, the expansion device, and the heat absorber, and configured to allow refrigerant to circulate.