Refrigerating apparatus

Patent metadata

Field	Value
Publication number	US-9353976-B2
Application number	US-97633210-A
Country	US
Kind code	B2
Filing date	Dec 22, 2010
Priority date	Dec 25, 2009
Publication date	May 31, 2016
Grant date	May 31, 2016

Abstract

An object of the present invention is to keep an appropriate amount of a refrigerant to be circulated through a refrigerant circuit and prevent an overload operation of compression means due to high pressure abnormality in a refrigerating apparatus which obtains a supercritical pressure on a high pressure side. The refrigerating apparatus which obtains the supercritical pressure on the high pressure side comprises a refrigerant amount regulation tank connected to the refrigerant circuit on the high pressure side via a communicating circuit; a communicating circuit which connects the upper part of this tank to a medium pressure region of the refrigerant circuit; a communicating circuit which connects the lower part of the tank to the medium pressure region of the refrigerant circuit; an electromotive expansion valve of the communicating circuit; an electromagnetic valve of the communicating circuit; an electromagnetic valve of the communicating circuit; and control means for controlling these valves to collect a refrigerant circulated through the refrigerant circuit in the tank and discharging the refrigerant to the refrigerant circuit.

First claim

What is claimed is:

1. A refrigerating apparatus in which a first refrigerant circuit is provided with compression means, a gas cooler, reducing means and an evaporator to obtain a supercritical pressure on a high pressure side, the compression means comprises first and second compression elements, and sucks the refrigerant from the first refrigerant circuit on a low pressure side into the first compression element to compress the refrigerant, sucks the refrigerant discharged from the first compression element and having a medium pressure into the second compression element to compress the refrigerant, and discharges the refrigerant to the first refrigerant circuit on the high pressure side, the refrigerating apparatus comprising:
a second refrigerant circuit which one end is connected to the high pressure side of the first refrigerant circuit and other end is connected to a medium pressure region of the first refrigerant circuit,
wherein the second refrigerant circuit comprising;
a first communicating circuit which is branched from the high pressure side of the first refrigerant circuit;
a refrigerant amount regulation tank which one end is connected to the first communicating circuit;
a second communicating circuit which connects the upper part of the refrigerant amount regulation tank to a medium pressure region of the first refrigerant circuit;
a third communicating circuit which connects the lower part of the refrigerant amount regulation tank to the medium pressure region of the first refrigerant circuit;
an electromotive expansion valve disposed in the first communicating circuit;
a first valve device disposed in the second communicating circuit;
a second valve device disposed in the third communicating circuit; and
control means for controlling the electromotive expansion valve and the respective valve devices,
wherein the control means opens the electromotive expansion valve and the first valve device while the second valve device is closed when executing a refrigerant collecting operation of collecting a refrigerant circulated through the first refrigerant circuit in the refrigerant amount regulation tank, and the control means opens the second valve device while the electromotive expansion valve and the first valve device are closed when executing a refrigerant discharging operation of discharging the refrigerant from the refrigerant amount regulation tank to the first refrigerant circuit, and
the control means closes the respective valve devices and opens the electromotive expansion valve when executing a refrigerant holding operation of holding the refrigerant in the refrigerant amount regulation tank.

2. The refrigerating apparatus according to claim 1 , wherein the control means sets the open degree of the electromotive expansion valve during the refrigerant holding operation to be smaller than the open degree thereof during the refrigerant collecting operation.

3. The refrigerating apparatus according to claim 2 , wherein based on a high pressure side pressure of the first refrigerant circuit, the control means executes the refrigerant collecting operation when the high pressure side pressure rises, and executes the refrigerant discharging operation when the high pressure side pressure lowers.

4. The refrigerating apparatus according to claim 3 , wherein the control means executes the refrigerant collecting operation in a case where the high pressure side pressure exceeds a predetermined collecting threshold value or on conditions that the high pressure side pressure exceeds a predetermined collecting protection value which is lower than the collecting threshold value and that the revolution speed of a blower which air-cools the gas cooler reaches a maximum value, and the control means ends the refrigerant collecting operation to shift to the refrigerant holding operation in a case where the high pressure side pressure lowers to be not higher than the collecting protection value, and
the control means executes the refrigerant discharging operation in a case where the high pressure side pressure lowers below a predetermined discharge threshold value which is lower than the collecting protection value or on conditions that the high pressure side pressure is not higher than the collecting protection value and that the revolution speed of the blower is not higher than a predetermined standard value which is lower than the maximum value, and the control means ends the refrigerant discharging operation to shift to the refrigerant holding operation in a case where the high pressure side pressure exceeds the collecting protection value.

5. The refrigerating apparatus according to claim 1 , wherein
the refrigerating apparatus further comprising an intercooler which air-cools the refrigerant discharged from the first compression element, wherein the second and third communicating circuits are connected to the intercooler on an outlet side.

6. The refrigerating apparatus according to claim 1 , wherein carbon dioxide is used as the refrigerant.

Assignees

• Mihara Kazuhiko
• Sasaki Hidetaka
• Hasegawa Setsu
• Kawakubo Ken
• Otake Masahisa
• Panasonic Ip Man Co Ltd

Inventors

• Mihara Kazuhiko
• Sasaki Hidetaka
• Hasegawa Setsu
• Kawakubo Ken
• Otake Masahisa

Classifications

• F25B9/008 Primary

  the refrigerant being carbon dioxide · CPC title

• F25B2309/061

  with cycle highest pressure above the supercritical pressure · CPC title

• F25B2400/16

  Receivers · CPC title

• F25B2700/2106

  of fresh outdoor air · CPC title

• F25B2600/17

  by controlling the pressure of the condenser · CPC title