Refrigeration Cycle

Abstract

Provided is a refrigeration cycle wherein a compressor, a condenser, a depressurizing/expanding means and an evaporator are provided. The refrigeration cycle uses R1234 as a refrigerant, and has an oil separating means, which forcibly separates the refrigerant and oil one from the other, in a two-phase separation region wherein the refrigerant and the oil exist in a separated state without being dissolved with each other. The refrigerant and the oil can be forcibly separated suitably at a suitable position even when the refrigerant is changed to the new refrigerant R1234yf, and the refrigeration cycle can be operated at a high efficiency as a whole.

1 . A refrigeration cycle having a compressor for compressing refrigerant, a condenser for condensing compressed refrigerant, a depressurizing/expanding means for depressurizing and expanding condensed refrigerant, and an evaporator for evaporating depressurized and expanded refrigerant in this order in a refrigerant flowing direction, characterized in that R1234yf is used as said refrigerant, and an oil separating means for forcibly separating said refrigerant and oil one from the other is provided in a two-phase separation region, in which said refrigerant and said oil exist in a separate state without being dissolved with each other, present in a route from an exit side of said compressor to said depressurizing/expanding means. 
     
     
         2 . The refrigeration cycle according to  claim 1 , wherein said oil separating means is provided at a position between said condenser and said depressurizing/expanding means. 
     
     
         3 . The refrigeration cycle according to  claim 1 , wherein an oil return line for returning oil separated by said oil separating means to said compressor is provided between said oil separating means and said compressor. 
     
     
         4 . The refrigeration cycle according to  claim 1 , wherein a sight glass capable of monitoring behavior of said refrigerant present inside is provided at a downstream side of said oil separating means as viewed in a refrigerant circulation direction. 
     
     
         5 . The refrigeration cycle according to  claim 1 , wherein said oil comprises polyalkylene glycol. 
     
     
         6 . The refrigeration cycle according to  claim 1 , wherein said oil separating means is disposed at a higher position than said compressor in a vertical direction. 
     
     
         7 . The refrigeration cycle according to  claim 1 , wherein said oil separating means has a centrifugal separation means for separating said refrigerant and said oil by centrifuging said refrigerant and said oil. 
     
     
         8 . The refrigeration cycle according to  claim 1 , wherein said oil separating means has a collision separation means for separating said refrigerant and said oil by a collision of said refrigerant and said oil. 
     
     
         9 . The refrigeration cycle according to  claim 1 , wherein said oil separating means has a trap separation means for separating said refrigerant and said oil by trapping said oil from said refrigerant and said oil. 
     
     
         10 . The refrigeration cycle according to  claim 1 , wherein said oil separating means has a centrifugal separation means for separating said refrigerant and said oil by centrifuging said refrigerant and said oil and a trap separation means for separating said refrigerant and said oil by trapping said oil from said refrigerant and said oil. 
     
     
         11 . The refrigeration cycle according to  claim 1 , wherein said oil separating means has a collision separation means for separating said refrigerant and said oil by a collision of said refrigerant and said oil and a trap separation means for separating said refrigerant and said oil by trapping said oil from said refrigerant and said oil. 
     
     
         12 . The refrigeration cycle according to  claim 1 , wherein a temporary storage section for separated oil is provided at a lower position in a vertical direction in said oil separating means. 
     
     
         13 . The refrigeration cycle according to  claim 1 , wherein an exit for separated oil is provided at a lower end in a vertical direction of said oil separating means. 
     
     
         14 . The refrigeration cycle according to  claim 1 , wherein said refrigeration cycle is used in an air conditioning system for vehicles.