Refrigeration apparatus

Patent metadata

Field	Value
Publication number	US-11041666-B2
Application number	US-201716342351-A
Country	US
Kind code	B2
Filing date	Oct 17, 2017
Priority date	Oct 17, 2016
Publication date	Jun 22, 2021
Grant date	Jun 22, 2021

Abstract

Provided is a refrigeration apparatus that secures safety while suppressing an increase in cost. A refrigeration apparatus performs a refrigeration cycle in a refrigerant circuit including a compressor, a heat source-side heat exchanger, and a usage-side heat exchanger. The refrigeration apparatus comprises a usage-side fan providing an air flow, and a controller. The usage-side fan is disposed in a target space where inside air is cooled. The controller performs a refrigerant leak determination process to determine whether a refrigerant leak occurs, based on a state of a refrigerant in the refrigerant circuit. When the controller performs the refrigerant leak determination process to determine that a refrigerant leak occurs, then the controller performs leakage refrigerant agitation control to operate the usage-side fan so as to suppress local emergence of a region where the refrigerant leaks at a high concentration in the target space.

First claim

The invention claimed is:

1. A refrigeration apparatus for a refrigeration cycle in a refrigerant circuit including a compressor configured to compress a refrigerant, a heat source-side heat exchanger, and a usage-side heat exchanger disposed in a target space to be cooled or heated,
the refrigeration apparatus comprising:
a fan disposed in the target space and configured to provide an air flow;
an interruption valve to be switched to a closed state to interrupt a flow of the refrigerant from an outside of the target space into an inside of the target space; and
a controller configured to control operation of each of a plurality of actuators,
the controller being configured to make a first and a second refrigerant leak determinations as to whether a refrigerant leak occurs, based on a state of the refrigerant in the refrigerant circuit,
when the controller makes the first refrigerant leak determination to determine that a refrigerant leak occurs, then the controller performs first control to bring the interruption valve into the closed state so as to perform a pump down operation to recover the refrigerant into a component disposed outside the target space, and stops the compressor after completion of the pump down operation subsequent to the first control, then,
the controller makes the second refrigerant leak determination to determine whether a refrigerant leak occurs at the target space, and
when the controller makes the second refrigerant leak determination to determine that a refrigerant leak occurs at the target space, then the controller performs the second control.

2. The refrigeration apparatus according to claim 1 , further comprising:
a pressure sensor configured to detect a pressure of low-pressure refrigerant in the refrigerant circuit,
wherein the controller makes the first or second refrigerant leak determination to determine that a refrigerant leak occurs, when a value detected by the pressure sensor is equal to or less than a predetermined first reference value.

3. The refrigeration apparatus according to claim 2 , wherein the first reference value is a value equivalent to an atmospheric pressure.

4. The refrigeration apparatus according to claim 1 , further comprising:
a temperature sensor configured to detect a temperature of the refrigerant to be discharged from the compressor,
wherein the controller makes the first or second refrigerant leak determination to determine that a refrigerant leak occurs, when a value detected by the temperature sensor is equal to or more than a predetermined second reference value.

5. The refrigeration apparatus according to claim 2 , further comprising:
a temperature sensor configured to detect a temperature of the refrigerant to be discharged from the compressor,
wherein the controller makes the first or second refrigerant leak determination to determine that a refrigerant leak occurs, when a value detected by the temperature sensor is equal to or more than a predetermined second reference value.

6. The refrigeration apparatus according to claim 3 , further comprising:
a temperature sensor configured to detect a temperature of the refrigerant to be discharged from the compressor,
wherein the controller makes the first or second refrigerant leak determination to determine that a refrigerant leak occurs, when a value detected by the temperature sensor is equal to or more than a predetermined second reference value.

Assignees

• Daikin Ind Ltd

Inventors

• Sakae Satoru
• Nakayama Takahito
• Mezaki Takenori

Classifications

• F25B49/005 Primary

  of safety devices (F25B49/02 and F25B49/04 take precedence) · CPC title

• F25B41/24

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

• F25B41/20

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

• F25B49/02 Primary

  for compression type machines, plants or systems · CPC title

• F25B2600/2515

  Flow valves · CPC title