Freezing device
View Patent ↗An object is to provide a freezing device in which a safely-treatable incombustible mixed refrigerant can be used and which can realize an extremely low temperature of −85° C. or less in chamber by a simple structure. The freezing device comprises a single refrigerant circuit in which the refrigerant discharged from a compressor is condensed and thereafter evaporated to exert a cooling function and which allows heat exchange between the evaporated refrigerant and the condensed refrigerant, wherein there is introduced into the refrigerant circuit a non-azeotropic mixed refrigerant containing R245fa, R600, R23 and R14; a non-azeotropic mixed refrigerant containing R245fa, R600, R116 and R14; a non-azeotropic mixed refrigerant containing R245fa, R600, R508A and R14; or a non-azeotropic mixed refrigerant containing R245fa, R600, R508B and R14.
1. A freezing device comprising:
a single refrigerant circuit in which a refrigerant discharged from a compressor is condensed and then evaporated to exert a cooling function and which allows heat exchange between the evaporated refrigerant and the condensed refrigerant,
wherein there is introduced into the refrigerant circuit:
a non-chlorine-containing and a non-azeotropic mixed refrigerant containing R245fa, R600, R23 and R14;
a non-chlorine-containing and a non-azeotropic mixed refrigerant containing R245fa, R600, R116 and R14;
a non-chlorine-containing and a non-azeotropic mixed refrigerant containing R245fa, R600, R508A and R14; or
a non-chlorine-containing and a non-azeotropic mixed refrigerant containing R245fa, R600, R508B and R14; wherein
with respect to a total weight of the non-azeotropic mixed refrigerant,
a total weight ratio of the refrigerants R245fa and R600 is set to a range of 40 wt % to 80 wt %,
a weight ratio of the refrigerant R23, R116, R508A or R508B is set to a range of 15 wt % to 47 wt %, and
a weight ratio of the refrigerant R14 is set to a range of 3 wt % to 20 wt %; and wherein
R245fa and R600 are mixed at a ratio so as to be incombustible.
2. The freezing device according to claim 1 , wherein R245fa and R600 are mixed at a weight ratio of R245fa/R600 equals 70/30.
3. The freezing device according to claim 2 , wherein with respect to the total weight of the non-azeotropic mixed refrigerant,
the total weight ratio of the refrigerants R245fa and R600 is set to a range of 49 wt % to 70 wt %;
the weight ratio of the refrigerant R23, R116, R508A or R508B is set to a range of 21 wt % to 42 wt %, and
the weight ratio of the refrigerant R14 is set to a range of 9 wt % to 20 wt %.
4. The freezing device according to claim 3 , wherein with respect to the total weight of the non-azeotropic mixed refrigerant,
the total weight ratio of the refrigerants R245fa and R600 is set to 64 wt %,
the weight ratio of the refrigerant R23, R116, R508A or R508B is et to 24 wt %, and
the weight ratio of the refrigerant R14 is set to 12 wt %.