US 11,965,683 B2
Cooling system for low temperature storage
Byoungjin Ryu, Seoul (KR); Yoonho Yoo, Seoul (KR); and Jaeheuk Choi, Seoul (KR)
Assigned to LG ELECTRONICS INC., Seoul (KR)
Appl. No. 17/047,205
Filed by LG ELECTRONICS INC., Seoul (KR)
PCT Filed Apr. 19, 2019, PCT No. PCT/KR2019/004777
§ 371(c)(1), (2) Date Oct. 13, 2020,
PCT Pub. No. WO2019/203620, PCT Pub. Date Oct. 24, 2019.
Claims priority of application No. 10-2018-0046186 (KR), filed on Apr. 20, 2018.
Prior Publication US 2021/0164711 A1, Jun. 3, 2021
Int. Cl. F25B 47/02 (2006.01); F25B 41/20 (2021.01); F25B 41/24 (2021.01)
CPC F25B 47/022 (2013.01) [F25B 41/20 (2021.01); F25B 41/24 (2021.01); F25B 2313/007 (2013.01); F25B 2313/0231 (2013.01); F25B 2313/02322 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A cooling system for cold storage, comprising:
a compressor configured to compress a refrigerant;
an outdoor heat exchanger disposed at an outlet side of the compressor;
a first outdoor valve disposed between the compressor and the outdoor heat exchanger to selectively restrict inflow of the refrigerant into the outdoor heat exchanger;
a first bypass pipe branched from an inlet side of the first outdoor valve to guide the refrigerant to bypass the outdoor heat exchanger;
a suction connection pipe branched from an outlet side of the first outdoor valve to guide the refrigerant passing through the outdoor heat exchanger to a suction side of the compressor;
a first evaporator into which the refrigerant flowing through the first bypass pipe is introduced to perform defrost;
a second evaporator disposed at an outlet side of the first evaporator to evaporate the refrigerant passing through the first evaporator;
a discharge pipe configured to extend from the outlet side of the compressor to the outdoor heat exchanger;
a liquid pipe disposed at an outlet side of the outdoor heat exchanger, the refrigerant condensed in the outdoor heat exchanger flowing through the liquid pipe;
a first branch portion connected to a first end of the first bypass pipe;
a second branch portion to which the suction connection pipe is connected;
a third branch portion formed in the liquid pipe;
a second bypass pipe connected to the third branch portion, the refrigerant used to defrost the first evaporator flowing through the second bypass pipe;
a first connection pipe connected to the liquid pipe and at which a first defrost valve is disposed;
a third bypass pipe branched from the first connection pipe to guide the refrigerant to the first evaporator;
a first evaporator outlet pipe connected to the first evaporator;
a second defrost valve connected to the third bypass pipe and the first evaporator outlet pipe;
a connection pipe branched from the third bypass pipe;
a second evaporator outlet pipe connected to the second evaporator; and
a third defrost valve connected to the connection pipe and the second evaporator outlet pipe, wherein the refrigerant compressed by the compressor is restricted from being immediately introduced into the outdoor heat exchanger and instead flows into the first evaporator through the first bypass pipe to perform defrosting during a defrosting operation.