REFRIGERANT CHARGING DEVICE, REFRIGERATION DEVICE, AND REFRIGERANT CHARGING METHOD

• US 20100107660A1
• Filed: 04/07/2008
• Published: 05/06/2010
• Est. Priority Date: 04/13/2007
• Status: Active Grant

• Current Assignee: Daikin Industries Ltd
• Original Assignee: Daikin Industries Ltd
• Inventors: Tani, Kazuhiko, Oka, Masahiro, Okamoto, Atsushi, Kawano, Satoshi
• Granted Patent: US 9,303,907 B2
• Time in Patent Office: Days
• US Class Current: 62/77
• CPC Class Codes: F25B 2345/001 Charging refrigerant to a cycle
• CPC Class Codes: F25B 2600/2515 Flow valves
• CPC Class Codes: F25B 2700/1933 Suction pressures
• CPC Class Codes: F25B 2700/2106 of fresh outdoor air
• CPC Class Codes: F25B 45/00 Arrangements for charging or discharging refrigerant

Abstract

A refrigerant charging device includes: an electric valve provided in a supply pipe; a flow rate control unit for controlling the degree of opening of the electric valve such that the flow rate in the supply pipe lies within a predetermined range, on the basis of a pressure difference between pressure of refrigerant supplied to the supply pipe and the pressure of refrigerant on the suction side of a compressor; an outdoor air temperature sensor for detecting outdoor air temperature; and a low-pressure side pressure sensor for detecting refrigerant pressure on the suction side of the compressor. The pressure difference is a difference between a saturation pressure corresponding to the outdoor air temperature detected by the outdoor air temperature sensor and refrigerant pressure detected by the low-pressure side pressure sensor.

Claims

1. A refrigerant charging device which has a supply pipe connectable to refrigerant piping on a suction side of a compression mechanism in a refrigerant circuit, and which supplies refrigerant to the refrigerant circuit via the supply pipe, comprising:

adjustment portion for adjusting a flow rate in the supply pipe to be within a predetermined range, based on a pressure difference between a pressure of refrigerant supplied to the supply pipe and a refrigerant pressure on the suction side of the compression mechanism.

2. The refrigerant charging device according to claim 1, comprising:

outdoor air temperature detection portion for detecting outdoor air temperature; and

pressure detection portion for detecting the refrigerant pressure on the suction side of the compression mechanism, wherein

the adjustment portion adjusts the flow rate in the supply pipe based on a pressure difference between a saturation pressure corresponding to the outdoor air temperature detected by the outdoor air temperature detection portion and a refrigerant pressure detected by the pressure detection portion.

3. The refrigerant charging device according to claim 1, wherein the adjustment portion comprises an electric valve provided in the supply pipe, and a flow rate control unit that controls a degree of opening of the electric valve.

4. The refrigerant charging device according to claim 3, comprising a correction control unit for correcting the degree of opening of the electric valve, controlled by the flow rate control unit, such that superheat of refrigerant on the discharge side of the compression mechanism becomes equal to or greater than a predetermined value.

5. The refrigerant charging device according to claim 4, wherein the correction control unit increases the degree of opening of the electric valve when the superheat of the refrigerant on the discharge side of the compression mechanism reaches an upper limit equal to or greater than the predetermined value.

6. The refrigerant charging device according to claim 4, wherein the superheat of the refrigerant on the discharge side of the compression mechanism is derived from refrigerant temperature and a saturation temperature corresponding to refrigerant pressure on the discharge side of the compression mechanism.

7. The refrigerant charging device according to claim 1, comprising a charging completion control unit that closes the electric valve when a predetermined amount of refrigerant is supplied via the supply pipe.

8. A refrigeration device comprising:

a refrigerant circuit in which refrigerant circulates between a compression mechanism, a condenser, an expansion mechanism and an evaporator; and

the refrigerant charging device according to claim 1, wherein

the supply pipe of the refrigerant charging device is connected to refrigerant piping between the compression mechanism and the evaporator.

9. A refrigerant charging method for charging refrigerant via a supply pipe that is connected to refrigerant piping on a suction side of a compression mechanism in a refrigerant circuit, the method comprising:

supplying the refrigerant to the refrigerant circuit while adjusting a flow rate in the supply pipe to be within a predetermined range, on the basis of a pressure difference between a pressure of refrigerant supplied to the supply pipe and a refrigerant pressure on the suction side of the compression mechanism.

10. The refrigerant charging method according to claim 9, wherein the flow rate in the supply pipe is adjusted on the basis of a pressure difference between a saturation pressure corresponding to outdoor air temperature, and a refrigerant pressure on the suction side of the compression mechanism.

11. The refrigerant charging method according to claim 9, wherein refrigerant is supplied to the refrigerant circuit while the flow rate in the supply pipe is adjusted to be within a predetermined range through adjustment of a degree of opening of an electric valve provided in the supply pipe.

12. The refrigerant charging method according to claim 11, wherein the degree of opening of the electric valve is corrected such that superheat of the refrigerant on the discharge side of a compression mechanism is equal to or greater than a predetermined value.

13. The refrigerant charging method according to claim 12, wherein the degree of opening of the electric valve is increased when the superheat of the refrigerant on the discharge side of the compression mechanism reaches an upper limit equal to or greater than the predetermined value.

14. The refrigerant charging method according to claim 11, wherein the electric valve is closed when a predetermined amount of refrigerant is supplied via the supply pipe.