Refrigeration circuit

Abstract

Disclosed is a refrigeration circuit for a vehicle air-conditioning system provided with a compressor, a condenser, a pressure-reduction/expansion means and an evaporator in this order, wherein R1234yf is used as the refrigerant and a shut-off valve for shutting off the circuit based on an excessive acceleration signal of the vehicle is provided in the circuit each of upstream and downstream of the condenser. When the refrigerant used is changed to R1234yf, which is a new-type refrigerant, it is possible to instantaneously minimize refrigerant leakage from the circuit in the event applied with an excessive impact, and to reduce the possibility of a fire starting or the like.

1 . A refrigeration circuit for a vehicle air-conditioning system comprising a compressor for compressing refrigerant, a condenser for condensing compressed refrigerant, a pressure reduction and expansion means for reducing in pressure and expanding condensed refrigerant, and an evaporator for evaporating pressure-reduced and expanded refrigerant in this order, characterized in that R1234yf is used as refrigerant and a shut-off valve for shutting off said circuit based on an excessive acceleration signal of said vehicle is provided at a position in said circuit each of upstream and downstream of said condenser. 
     
     
         2 . The refrigeration circuit for a vehicle air-conditioning system according to  claim 1 , wherein said excessive acceleration signal is a signal from an acceleration sensor mounted on said vehicle. 
     
     
         3 . The refrigeration circuit for a vehicle air-conditioning system according to  claim 1 , wherein said excessive acceleration signal is a signal from a collision sensor provided on an airbag.