Refrigeration apparatus with leak detection on the usage side and a refrigerant release mechanism

Patent metadata

Field	Value
Publication number	US-11280523-B2
Application number	US-201816485675-A
Country	US
Kind code	B2
Filing date	Feb 14, 2018
Priority date	Feb 14, 2017
Publication date	Mar 22, 2022
Grant date	Mar 22, 2022

Abstract

Provided is a refrigeration apparatus with improved safety. A refrigeration apparatus includes: a compressor; a heat source-side expansion valve to be controlled to have a minimum opening degree and brought into a closed state in which the heat source-side expansion valve maximizes prevention of a flow of a refrigerant toward a usage-side refrigerant circuit; a fusible plug; a controller; and a refrigerant leak detector configured to detect a refrigerant leak at the usage-side refrigerant circuit. The fusible plug is disposed in a refrigerant circuit, and is brought into an open state to allow the refrigerant circuit to communicate with an external space. When the refrigerant leak detector detects a refrigerant leak at the usage-side refrigerant circuit, the controller performs refrigerant leak first control to bring the heat source-side expansion valve into the closed state, and performs refrigerant leak second control to bring the fusible plug into the open state.

First claim

The invention claimed is:

1. A refrigeration apparatus having a refrigerant circuit including a heat source side circuit and a usage-side circuit, for a refrigeration cycle in the refrigerant circuit,
the refrigeration apparatus comprising:
a compressor disposed in the refrigerant circuit and configured to compress a refrigerant;
a first control valve to be controlled to be brought into a closed state in which the first control valve maximizes prevention of a flow of the refrigerant toward the usage-side circuit,
the first control valve being disposed upstream of the usage-side circuit with regard to a flow of the refrigerant in the refrigerant circuit;
a refrigerant releaser to be brought into an open state to allow the refrigerant circuit to communicate with an external space,
the refrigerant releaser being disposed in the refrigerant circuit;
a controller configured to control states of the respective components; and
a refrigerant leak detector configured to detect a refrigerant leak at the usage-side circuit by detecting a state of the refrigerant in the usage-side circuit or the refrigerant flowing out of the usage-side circuit,
wherein
the controller performs a first control and a second control when the refrigerant leak detector detects a refrigerant leak at the usage-side circuit,
the controller performs the first control to bring the first control valve into the closed state,
the controller performs the second control to bring the refrigerant releaser into the open state, the controller performs the second control after performing the first control, and
the refrigerant releaser is a fusible plug that melts by heat at a predetermined first temperature or more so as to be brought into the open state,
the heat source side circuit of the refrigeration apparatus further comprising:
a heater configured to directly or independently apply heat to the fusible plug, and
a heating temperature detector configured to detect a temperature of the heater,
wherein
the controller performs the second control to cause the heater to apply heat to the fusible plug to the first temperature, and
the controller performs the second control to control a state of the heater based on a value detected by the heating temperature detector.

2. A refrigeration apparatus having a refrigerant including a heat source side circuit and a usage-side circuit, for a refrigeration cycle in the refrigerant circuit,
the refrigerant apparatus comprising:
a compressor disposed in the refrigerant circuit and configured to compress a refrigerant;
a first control valve to be controlled to be brought into a closed state in which the first control valve maximizes prevention of a flow of the refrigerant toward the usage-side circuit,
the first control valve being disposed upstream of the usage-side circuit with regard to a flow of the refrigerant in the refrigerant circuit;
a refrigerant releaser to be brought into an open state to allow the refrigerant circuit to communicate with an external space,
the refrigerant releaser being disposed in the refrigerant circuit;
a controller configured to control states of the respective components; and
a refrigerant leak detector configured to detect a refrigerant leak at the usage-side circuit by detecting a state of the refrigerant in the usage-side circuit or the refrigerant flowing out of the out of the usage-side circuit,
wherein
the controller performs a first control and a second control when the refrigerant leak detector detects a refrigerant leak at the usage-side circuit,
the controller performs the first control to bring the first control valve into the closed state,
the controller performs the second control to bring the refrigerant releaser into the open state, the controller performs the second control after performing the first control, and
the refrigerant releaser is a fusible plug that melts by heat at a predetermined first temperature or more so as to be brought into the open state,
the heat source side circuit of the refrigeration apparatus further comprising:
a heater configured to directly or indirectly apply heat to the fusible plug, and
a high-pressure refrigerant pipe through which the high-pressure hot gas refrigerant discharged from the compressor flows; and
a second control valve to be brought into a first state to allow the compressor to communicate with the high-pressure refrigerant pipe,
wherein
the controller performs the second control to cause the heater to apply heat to the fusible plug to the first temperature, and
the controller performs the second control to drive the compressor and to bring the second control valve into the first state such that the high-pressure refrigerant pipe functions as the heater.

3. A refrigeration apparatus having a refrigerant circuit including a heat source side circuit and a usage-side circuit, for a refrigerant cycle in the refrigerant circuit,
the refrigerant apparatus comprising:
a compressor disposed in the refrigerant circuit and configured to compress a refrigerant;
a first control valve to be controlled to be brought into a closed state in which the first control valve maximizes prevention of a flow of the refrigerant toward the usage-side circuit,
the first control valve being disposed upstream of the usage-side circuit with regard to a flow of the refrigerant in the refrigerant circuit,
a refrigerant releaser to be brought into an open state to allow the refrigerant circuit to communicate with an external space,
the refrigerant releaser being disposed in the refrigerant circuit;
a controller configured to control states of the respective components; and
a refrigerant leak detector configured to detect a refrigerant leak at the usage-side circuit by detecting a state of the refrigerant in the usage-side circuit or the refrigerant flowing out of the out of the usage-side circuit,
wherein
the controller performs a first control and a second control when the refrigerant leak detector detects a refrigerant leak at the usage-side circuit,
the controller performs the first control to bring the first control valve into the closed state,
the controller performs the second control to bring the refrigerant releaser into the open state, the controller performs the second control after performing the first control, and
the refrigerant releaser is s fusible plug that melts by heat at a predetermined first temperature or more so as to be brought into the open state,
the heat source side circuit of the refrigeration apparatus further comprising:
a heater configured to directly or indirectly apply heat to the fusible plug,
a fusible plug temperature detector configured to detect a temperature of the fusible plug; and
an output unit configured to output predetermined notification information,
wherein
the controller performs the second control to cause the heater to apply heat to the fusible plug to the first temperature, and
the controller causes the output unit to output the notification information when the refrigerant leak detector detects no refrigerant leak at the usage-side circuit and the fusible plug temperature detector detects that the temperature of the fusible plug is equal to or more than a second temperature lower than the first temperature.

4. A refrigeration apparatus having a refrigerant circuit including a heat source side circuit and a user-side circuit, for refrigeration cycle in the refrigerant circuit,
the refrigerant apparatus comprising:
a compressor disposed in the refrigerant circuit and configured to compress a refrigerant;
a first control valve to be controlled to be brought into a closed state in which the first control valve maximizes prevention of a flow of the refrigerant toward the usage-side circuit,
the first control valve being disposed upstream of the usage-side

Assignees

• Daikin Ind Ltd

Inventors

• Sakae Satoru
• Mezaki Takenori

Classifications

• F25B43/006 Primary

  Accumulators · CPC title

• F25B1/04 Primary

  with compressor of rotary type ({F25B1/005,} F25B1/10 take precedence) · CPC title

• F25B2400/19

  Pumping down refrigerant from one part of the cycle to another part of the cycle, e.g. when the cycle is changed from cooling to heating, or before a defrost cycle is started · CPC title

• F25B41/24

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

• F25B2400/04

  Refrigeration circuit bypassing means · CPC title