Rotary compressor

Abstract

A refrigerant being low in both ODP and GWP and containing at least hydrofluoroolefin having a double bond of carbon is used. By providing a first compression-chamber oil feed path for feeding refrigerating machine oil to a compression chamber 15 after the refrigerant has been enclosed therein, effects on the global environment can be suppressed and moreover temperature increases of the refrigerant due to re-expansion heating and feeding of high-temperature refrigerating machine oil can be suppressed, i.e., decomposition of the refrigerant can be inhibited.

1 . A rotary compressor in which
 a single refrigerant of hydrofluoroolefin having a double bond of carbon or a mixed refrigerant containing the hydrofluoroolefin is used, the rotary compressor comprising:   a compression chamber for compressing the refrigerant; and   a first compression-chamber oil feed path for feeding refrigerating machine oil to the compression chamber after the refrigerant has been enclosed therein.   
     
     
         2 . The rotary compressor according to  claim 1 , wherein the first compression-chamber oil feed path is intermittently closed. 
     
     
         3 . The rotary compressor according to  claim 1 , wherein
 the compression chamber is defined between a stationary scroll and a turning scroll by the stationary scroll and the turning scroll being engaged with each other, each of the stationary scroll and the turning scroll including an end plate and a lap being a volute-shaped wall formed on the end plate, the rotary compressor further comprising:   an oil storage section for storing the refrigerating machine oil therein; and   at least one or more second compression-chamber oil feed paths for feeding the refrigerating machine oil from the oil storage section to the compression chamber, and wherein   at least one of the second compression-chamber oil feed paths is the first compression-chamber oil feed path.   
     
     
         4 . The rotary compressor according to  claim 3 , wherein
 the compression chamber includes a first compression chamber formed outside the lap of the turning scroll, and a second compression chamber formed inside the lap of the turning scroll, and   in comparison between the first compression chamber and the second compression chamber, a feed rate of the refrigerating machine oil to one compression chamber having a longer leak length is larger than a feed rate of the refrigerating machine oil to the other compression chamber.   
     
     
         5 . The rotary compressor according to  claim 3 , wherein
 the compression chamber includes a first compression chamber formed outside the lap of the turning scroll, and a second compression chamber formed inside the lap of the turning scroll, and   in comparison between the first compression chamber and the second compression chamber, a feed rate of the refrigerating machine oil to one compression chamber having a higher capacity change rate is larger than a feed rate of the refrigerating machine oil to the other compression chamber.   
     
     
         6 . The rotary compressor according to  claim 3 , wherein the first compression-chamber oil feed path comprises: a lead-in path part provided in a back face of the turning scroll so as to allow the refrigerating machine oil to be led in from the oil storage section; an in-lap oil feed path part which is provided inside the lap of the turning scroll so as to be communicated with the lead-in path part and which has an opening in a lap top face; and a recess portion which is provided in the end plate of the stationary scroll and which is intermittently communicated with the opening of the in-lap oil feed path pan. 
     
     
         7 . The rotary compressor according to  claim 1 , wherein the refrigerant contains at least one of tetrafluoropropene or trifluoropropene, which is a kind of hydrofluoroolefin, and the refrigerant has a global warming, potential within a range of 5 to 750, desirably 5 to 350. 
     
     
         8 . The rotary compressor according to  claim 1 , wherein
 the refrigerant contains, as a principal ingredient, tetrafluoropropene or trifluoropropene, which is a kind of hydrofluoroolefin, and   difluoromethane and pentafluoroethane are mixed in the refrigerant so that its global warn potential falls within a range of 5 to 750, desirably 5 to 350.   
     
     
         9 . The rotary compressor according to  claim 1 , wherein the refrigerating machine oil is (1) polyoxyalkylene glycol, (2) polyvinyl ether, (3) poly(oxy)alkylene glycol or copolymer of its monoether and polyvinyl ether, (4) synthetic oil containing an oxygenated compound of polyol esters and polycarbonates, (5) synthetic oil containing alkylbenzenes as a principal ingredient, or (6) synthetic oil containing α-olefins as a principal ingredient.