Refrigeration cycle device

Patent metadata

Field	Value
Publication number	US-10493818-B2
Application number	US-201515316210-A
Country	US
Kind code	B2
Filing date	Jun 16, 2015
Priority date	Jun 27, 2014
Publication date	Dec 3, 2019
Grant date	Dec 3, 2019

Abstract

When performing dehumidification heating of a space to be air-conditioned, a refrigeration cycle device is switched to a refrigerant circuit in which a flow of a refrigerant flowing out of an interior radiator is branched, and one of the branched refrigerants is decompressed by an interior expansion valve to evaporate in an interior evaporator, while the other of the branched refrigerants flows into a high-pressure side refrigerant passage of an internal heat exchanger and is then decompressed by an exterior expansion valve to evaporate in an exterior heat exchanger. Further, in the refrigerant circuit, a flow of the refrigerant flowing out of the interior evaporator and a flow of the refrigerant flowing out of the exterior heat exchanger are merged into a low-pressure side refrigerant passage of the internal heat exchanger. Thus, the refrigerant flowing into the interior evaporator is prevented from becoming a liquid-phase refrigerant having an unnecessarily high degree of supercooling, thereby achieving appropriate dehumidification heating.

First claim

What is claimed is:

1. A refrigeration cycle device to be used for an air conditioner, the refrigeration cycle device comprising:
a compressor adapted to compress and discharge a refrigerant;
an interior radiator that heats ventilation air to be blown into a space to be air-conditioned, using a high-pressure side refrigerant in a cycle as a heat source;
an interior evaporator that cools the ventilation air by exchanging heat between a low-pressure side refrigerant in the cycle and the ventilation air before passing through the interior radiator;
an exterior heat exchanger that exchanges heat between the refrigerant and outside air;
a first decompression device that decompresses the refrigerant flowing into the interior evaporator;
a second decompression device that decompresses the refrigerant flowing into the exterior heat exchanger;
an internal heat exchanger that exchanges heat between the high-pressure side refrigerant and the low-pressure side refrigerant;
a bypass passage that allows the refrigerant to bypass a high-pressure side refrigerant passage of the internal heat exchanger;
an opening/closing device that opens and closes the bypass passage;
a branch portion that branches a flow of the refrigerant flowing out of the interior radiator;
a merging portion that merges a flow of the refrigerant flowing out of the interior evaporator with a flow of the refrigerant flowing out of the exterior heat exchanger; and
a refrigerant-circuit switching portion that switches a refrigerant circuit in the cycle, wherein
the refrigerant-circuit switching portion is configured to be switchable between a cooling refrigerant circuit and a dehumidification heating refrigerant circuit,
the cooling refrigerant circuit being adapted to allow the refrigerant discharged from the compressor to circulate through the exterior heat exchanger, the high-pressure side refrigerant passage, the first decompression device, the interior evaporator, the low-pressure side refrigerant passage, and a suction port side of the compressor in this order, in a state where the opening/closing device closes the bypass passage, and
the dehumidification heating refrigerant circuit being adapted to allow the refrigerant discharged from the compressor to circulate through the interior radiator, the branch portion, the first decompression device, the interior evaporator, the merging portion, and the suction port side of the compressor in this order, while simultaneously allowing the refrigerant discharged from the compressor to circulate through the interior radiator, the branch portion, the second decompression device, the exterior heat exchanger, the bypass passage, the merging portion, and the suction port side of the compressor in this order, in a state where the opening/closing device opens the bypass passage,
wherein the high-pressure side refrigerant passage of the internal heat exchanger is bypassed during operation of the dehumidification heating refrigerant circuit.

2. The refrigeration cycle device according to claim 1 , further comprising a gas-liquid separator disposed in a refrigerant flow path that leads from a refrigerant outflow port of the merging portion to an inflow port side of the low-pressure side refrigerant passage,
the gas-liquid separator being adapted to separate the refrigerant into a gas-phase refrigerant and a liquid-phase refrigerant, and allowing the separated gas-phase refrigerant to flow out to a downstream side of the refrigerant flow path.

3. The refrigeration cycle device according to claim 1 , further comprising:
an evaporation pressure adjustment valve that adjusts a refrigerant evaporation pressure in the interior evaporator to a predetermined reference evaporation pressure or higher.

4. A refrigeration cycle device to be used for an air conditioner, the refrigeration cycle device comprising:
a compressor adapted to compress and discharge a refrigerant;
an interior radiator that heats ventilation air to be blown into a space to be air-conditioned, using a high-pressure side refrigerant in a cycle as a heat source;
an interior evaporator that cools the ventilation air by exchanging heat between a low-pressure side refrigerant in the cycle and the ventilation air before passing through the interior radiator;
an exterior heat exchanger that exchanges heat between the refrigerant and outside air;
a first decompression device that decompresses the refrigerant flowing into the interior evaporator;
a second decompression device that decompresses the refrigerant flowing into the exterior heat exchanger;
an internal heat exchanger that exchanges heat between the high-pressure side refrigerant and the low-pressure side refrigerant;
a bypass passage that allows the refrigerant to bypass a high-pressure side refrigerant passage of the internal heat exchanger;
an opening/closing device that opens and closes the bypass passage;
a branch portion that branches a flow of the refrigerant flowing out of the interior radiator;
a merging portion that merges a flow of the refrigerant flowing out of the interior evaporator with a flow of the refrigerant flowing out of the exterior heat exchanger; and
a refrigerant-circuit switching portion that switches a refrigerant circuit in the cycle, wherein
the refrigerant-circuit switching portion is configured to be switchable between a cooling refrigerant circuit and a dehumidification heating refrigerant circuit,
the cooling refrigerant circuit being adapted to allow the refrigerant discharged from the compressor to circulate through the exterior heat exchanger, the high-pressure side refrigerant passage, the first decompression device, the interior evaporator, the low-pressure side refrigerant passage, and a suction port side of the compressor in this order, in a state where the opening/closing device closes the bypass passage, and
the dehumidification heating refrigerant circuit being adapted to allow the refrigerant discharged from the compressor to circulate through the interior radiator, the branch portion, the first decompression device, the interior evaporator, the merging portion, and the suction port side of the compressor in this order, while simultaneously allowing the refrigerant discharged from the compressor to circulate through the interior radiator, the branch portion, the second decompression device, the exterior heat exchanger, the bypass passage, the merging portion, and the suction port side of the compressor in this order, in a state where the opening/closing device opens the bypass passage,
wherein, an inlet of the bypass passage is located downstream of the exterior heat exchanger, the refrigerant-circuit switching portion is located upstream of the first decompression device, and the high-pressure side refrigerant passage and the low-pressure side refrigerant passage are located therebetween.

5. The refrigeration cycle device according to claim 4 , wherein the inlet of the bypass passage is located immediately downstream of the exterior heat exchanger.

6. The refrigeration cycle device according to claim 4 , further comprising:
an evaporation pressure adjustment valve that adjusts a refrigerant evaporation pressure in the interior evaporator to a predetermined reference evaporation pressure or higher.

7. The refrigeration cycle device according to claim 4 , further comprising a gas-liquid separator disposed in a refrigerant flow path that leads from a refrigerant outflow port of the merging portion to an inflow port side of the low-pressure side refrigerant passage,
the gas-liquid separator being adapted to separate the refrigerant into a gas-phase refrigerant and a liquid-phase refrigerant, and allowing the separated gas-phase refrigerant to flow out to a downstream side of the refrigerant flow

Assignees

• Denso Corp

Inventors

• Kuwahara Mikiharu

Classifications

• F25B2313/02732

  using two three-way valves · CPC title

• F25B5/02

  arranged in parallel · CPC title

• F25B49/02

  for compression type machines, plants or systems · CPC title

• B60H1/00392

  for electric vehicles having only electric drive means · CPC title

• B60H2001/3263

  of the refrigerant at an evaporating unit · CPC title