Refrigeration apparatus

Patent metadata

Field	Value
Publication number	US-11268740-B2
Application number	US-201716338257-A
Country	US
Kind code	B2
Filing date	Sep 29, 2017
Priority date	Sep 30, 2016
Publication date	Mar 8, 2022
Grant date	Mar 8, 2022

Abstract

An air conditioning system includes: outdoor and indoor heat exchangers; first, second, and third control valves, which block refrigerant flow when fully closed; and a pressure adjuster. The first and second control valves are disposed in a gas-side refrigerant flow path (GL) between the outdoor and indoor heat exchangers. The third control valve is disposed in a liquid-side refrigerant flow path (LL) between the outdoor and indoor heat exchangers. The pressure adjuster adjusts the pressure of refrigerant in an indoor-side refrigerant flow path (IL) between the first control valve and the second control valve or the third control valve and the indoor heat exchanger. The pressure adjuster includes a pressure adjusting valve that bypasses refrigerant in the indoor-side refrigerant flow path (IL) to an outdoor-side refrigerant flow path (OL) between the first control valve and the second control valve or the third control valve and the outdoor heat exchanger.

First claim

The invention claimed is:

1. A refrigeration apparatus that performs a refrigeration cycle in a refrigerant circuit, the refrigeration apparatus comprising:
a heat-source-side heat exchanger;
a utilization-side heat exchanger;
a first shutoff valve that is disposed in a gas-side refrigerant flow path disposed between the heat-source-side heat exchanger and the utilization-side heat exchanger and that blocks flow of refrigerant when fully closed;
a second shutoff valve that is disposed in a liquid-side refrigerant flow path disposed between the heat-source-side heat exchanger and the utilization-side heat exchanger and that blocks flow of refrigerant when fully closed; and
a pressure adjusting portion that adjusts a pressure of refrigerant in a utilization-side refrigerant flow path disposed between the first shutoff valve or the second shutoff valve and the utilization-side heat exchanger, wherein
the pressure adjusting portion includes a bypass mechanism that bypasses the refrigerant in the utilization-side refrigerant flow path to a heat-source-side refrigerant flow path disposed between the first shutoff valve or the second shutoff valve and the heat-source-side heat exchanger, wherein
the pressure adjusting portion further includes a bypass pipe that forms a bypass flow path extending from the utilization-side refrigerant flow path to the heat-source-side refrigerant flow path, and
the bypass mechanism is a pressure adjusting valve that is disposed in the bypass flow path and that opens the bypass flow path when the first shutoff valve and the second shutoff valve are fully closed, and the pressure of the refrigerant in the utilization-side refrigerant flow path becomes higher than or equal to a predetermined reference value.

2. The refrigeration apparatus according to claim 1 , wherein the pressure adjusting valve is a valve that allows refrigerant to pass therethrough when receiving a pressure higher than or equal to the reference value.

3. The refrigeration apparatus according to claim 2 , wherein the bypass flow path extends from the utilization-side refrigerant flow path to a heat-source-side first refrigerant flow path disposed between the first shutoff valve and the heat-source-side heat exchanger.

4. The refrigeration apparatus according to claim 2 , wherein the bypass flow path extends to a heat-source-side second refrigerant flow path disposed between the second shutoff valve and the heat-source-side heat exchanger.

5. The refrigeration apparatus according to claim 2 , further comprising:
an electric expansion valve that is disposed in a refrigerant flow path between the utilization-side heat exchanger and the second shutoff valve and that decompresses refrigerant that passes therethrough in accordance with an opening degree thereof, wherein
the electric expansion valve allows the refrigerant to pass therethrough even when the first shutoff valve and the second shutoff valve are fully closed.

6. The refrigeration apparatus according to claim 1 , wherein the bypass flow path extends from the utilization-side refrigerant flow path to a heat-source-side first refrigerant flow path disposed between the first shutoff valve and the heat-source-side heat exchanger.

7. The refrigeration apparatus according to claim 6 , wherein the bypass flow path extends to a heat-source-side second refrigerant flow path disposed between the second shutoff valve and the heat-source-side heat exchanger.

8. The refrigeration apparatus according to claim 6 , further comprising:
an electric expansion valve that is disposed in a refrigerant flow path between the utilization-side heat exchanger and the second shutoff valve and that decompresses refrigerant that passes therethrough in accordance with an opening degree thereof, wherein
the electric expansion valve allows the refrigerant to pass therethrough even when the first shutoff valve and the second shutoff valve are fully closed.

9. The refrigeration apparatus according to claim 1 , wherein the bypass flow path extends to a heat-source-side second refrigerant flow path disposed between the second shutoff valve and the heat-source-side heat exchanger.

10. The refrigeration apparatus according to claim 9 , further comprising:
an electric expansion valve that is disposed in a refrigerant flow path between the utilization-side heat exchanger and the second shutoff valve and that decompresses refrigerant that passes therethrough in accordance with an opening degree thereof, wherein
the electric expansion valve allows the refrigerant to pass therethrough even when the first shutoff valve and the second shutoff valve are fully closed.

11. The refrigeration apparatus according to claim 1 , further comprising:
an electric expansion valve that is disposed in a refrigerant flow path between the utilization-side heat exchanger and the second shutoff valve and that decompresses refrigerant that passes therethrough in accordance with an opening degree thereof, wherein
the electric expansion valve allows the refrigerant to pass therethrough even when the first shutoff valve and the second shutoff valve are fully closed.

12. The refrigeration apparatus according to claim 1 , further comprising:
a compressor that is disposed in a refrigerant flow path between the heat-source-side heat exchanger and the first shutoff valve and that compresses refrigerant; and
an accumulator that is disposed on a suction side of the compressor and that stores refrigerant.

13. The refrigeration apparatus according to claim 1 , further comprising:
a heat source unit in which the heat-source-side heat exchanger is disposed;
a plurality of utilization units in each of which the utilization-side heat exchanger is disposed; and
a first shutoff valve unit that is disposed in the gas-side refrigerant flow path disposed between the utilization units and the heat source unit and that blocks flow of refrigerant in corresponding one or more of the utilization units, wherein
the first shutoff valve and the pressure adjusting portion are disposed in the first shutoff valve unit.

14. The refrigeration apparatus according to claim 1 , further comprising:
a heat source unit in which the heat-source-side heat exchanger is disposed;
a plurality of utilization units in each of which the utilization-side heat exchanger is disposed;
a first shutoff valve unit that is disposed in the gas-side refrigerant flow path disposed between the utilization units and the heat source unit and that blocks flow of refrigerant in corresponding one or more of the utilization units; and
a second shutoff valve unit that is disposed in the liquid-side refrigerant flow path disposed between the utilization units and the heat source unit and that blocks flow of refrigerant in corresponding one or more of the utilization units, wherein
the first shutoff valve is disposed in the first shutoff valve unit,
the second shutoff valve is disposed in the second shutoff valve unit, and
the pressure adjusting portion is disposed in the first shutoff valve unit or the second shutoff valve unit, or the pressure adjusting portion is disposed in each of the first shutoff valve unit and the second shutoff valve unit.

15. The refrigeration apparatus according to claim 1 , further comprising:
a heat source unit in which the heat-source-side heat exchanger is disposed;
a plurality of utilization units in each of which the utilization-side heat exchanger is disposed and that are arranged in parallel with the heat source unit; and
a refrigerant-flow-path switch that is disposed in the gas-side refrigerant flow path and the liquid-side r

Assignees

• Daikin Ind Ltd

Inventors

• Yamada Takuro
• Nakagawa Yuusuke
• Oka Yuusuke
• Honda Masahiro

Classifications

• F25B2313/0232

  with bypasses · CPC title

• F25B2400/0409

  for evaporators · CPC title

• F25B2400/0403

  for condensers · CPC title

• F25B41/20 Primary

  Disposition of valves, e.g. of on-off valves or flow control valves (expansion valves F25B41/31) · CPC title

• F25B41/24

  Arrangement of shut-off valves for disconnecting a part of the refrigerant cycle, e.g. an outdoor part · CPC title