JP2000292015A - Motor cooling device for refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor cooling device for a refrigerator to effectively cool a motor even when the temperature of a condenser, such as operation of a refrigerator by a heat pump motor, is increased. SOLUTION: A motor cooling device for a refrigerator cools the motor of a refrigerator provided with an evaporator 1, a condenser 2, a multistage compressor 3, a motor 3-1 for driving the multistage compressor 3, and an economizer 4. A refrigerant introduction passage consisting of a piping 13 to introduce refrigerant for cooling an internal space 3-1a of the motor 3-1 and condensed by a condenser 2 to an internal space 3-1a of the motor 3-1, and a return pipe 14 for a refrigerant after cooling, are provided. Refrigerant liquid passing through the refrigerant introduction passage is excessively cooled through a small heat-exchanger 11 and fed to the internal space 3-1a and refrigerant liquid after cooling of the motor 3-1 is returned to the economizer 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerator motor cooling device for cooling a motor for driving a compressor of a refrigerator.

[0002]

2. Description of the Related Art Conventionally, as a motor cooling device for a refrigerator of this type, a refrigerant liquid condensed in a condenser is sent to an internal space of the motor, the motor is cooled, and the cooled refrigerant liquid is sent to an evaporator. And those that return to the condenser.

[0003]

However, the conventional motor cooling device has a problem that the motor cannot be sufficiently cooled. In particular, when the temperature of the condenser becomes high, such as when the refrigerator is operated in the heat pump mode, there is a problem that the motor cannot be sufficiently cooled.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has been made in view of the above circumstances. It is an object to provide a motor cooling device.

[0005]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a refrigerator having an evaporator, a condenser, a multi-stage compressor, and a motor for driving the multi-stage compressor. A motor cooling device, provided with a refrigerant introduction path for introducing the refrigerant liquid condensed in the condenser into the internal space of the motor, supercooling the refrigerant liquid passing through the refrigerant introduction path through an evaporator or a small heat exchanger. The refrigerant liquid is sent to the internal space of the motor, and after cooling the motor, the refrigerant liquid is returned to the economizer or the condenser.

[0006] As described above, the refrigerant liquid from the condenser is supercooled through the evaporator or the small heat exchanger and sent to the internal space of the motor, and the motor is cooled. By operating the refrigerator in the heat pump mode, the motor can be sufficiently cooled even when the temperature of the condenser becomes high.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a configuration example of a refrigerator having a motor cooling device according to the present invention. As shown in the drawing, the present refrigerator is configured to include an evaporator 1, a condenser 2, a multi-stage compressor 3, and an economizer 4. The multi-stage compressor 3 has a configuration in which a low-stage compression unit 3-2 and a high-stage compression unit 3-3 each having an impeller are arranged on both sides of a motor 3-1. The economizer 4 here has a two-stage configuration.

In the refrigerator having the above structure, the multi-stage compressor 3
When the motor 3-1 is started to rotate the impellers of the low-stage compression unit 3-2 and the high-stage compression unit 3-3, the refrigerant vapor from the evaporator 1 passes through the pipe 5 and passes through the multistage compressor 3 Is sucked and compressed from the suction port of the low-stage compression unit 3-2, and further passes through the communication pipe 3-4 connecting the discharge port of the low-stage compression unit 3-2 and the suction port of the high-stage compression unit 3-3. It is sent to the high-stage compression unit 3-3 and compressed.

The refrigerant vapor compressed by the high-stage compression unit 3-3 is sent to the condenser 2 through the pipe 6, and is condensed in the condenser 2 to form a refrigerant liquid. The refrigerant liquid is sent to the economizer 4 through the pipe 7 and decompressed, and then separated into gas and liquid. The gas phase (refrigerant vapor) passes through the pipe 8 to the high-stage compression unit 3-3 of the multi-stage compressor 3. After being sent, the liquid phase (refrigerant liquid) is sent to the second stage (lower stage side) after being decompressed, where it is again gas-liquid separated, and the gas phase component passes through the pipe 9 and passes through the lower stage compression unit 3-2.
The liquid phase (refrigerant liquid) is sent to the evaporator 1 through the pipe 10. In the evaporator 1, heat is exchanged with the liquid passing through the heat transfer tube group 1-1 disposed in the evaporator 1, and the refrigerant liquid becomes refrigerant vapor.

A motor cooling device for cooling the motor 3-1 of the multi-stage compressor 3 extracts a part of the refrigerant liquid sent from the condenser 2 to the economizer 4 through the pipe 7 and passes through the small heat exchanger 11. The supercooled refrigerant liquid is pumped by pump 1
2 through the pipe 13 to the internal space 3- of the motor 3-1.
1a to cool the motor 3-1. The refrigerant liquid that has cooled the motor 3-1 is sent to the economizer 4 through the pipe 14.

FIG. 2 is a diagram showing an example of the configuration of the small heat exchanger 11. As shown in FIG. As shown in the drawing, the refrigerant liquid from the evaporator 1 is supplied to the small heat exchanger 11, and the refrigerant liquid sent from the condenser 2 to the internal space 3-1a of the motor 3-1 through the pipe 13 is supercooled. I have. Also, the internal space 3-1 of the motor 3-1
As shown in FIG. 3, a method of subcooling the refrigerant liquid sent to the evaporator 1 is to provide a heat transfer tube 1-2 inside the evaporator 1 and pass the heat transfer tube 1-2 through the pipe 13 to the inside of the motor 3-1. Space 3-
The refrigerant liquid from the condenser 2 sent to 1a may be supercooled.

As described above, the internal space 3 of the motor 3-1
-1a is provided with a pipe (refrigerant introduction path) 13 for introducing the refrigerant liquid, and the refrigerant liquid condensed by the condenser 2 in the internal space 3-1a of the motor 3-1 is supercooled through the evaporator 1 or the small heat exchanger 11. By returning the refrigerant liquid after cooling the motor 3-1 to the economizer 4, the motor 3-1 is sufficiently cooled even when the refrigerator is operated in the heat pump mode in which the internal temperature of the condenser 2 becomes high. It is possible to do.

Although illustration is omitted, when the internal temperature of the condenser 2 is standard, the motor 3-1 is returned to the condenser 2 after cooling the motor 3-1. It can be cooled sufficiently.

[0014]

As described above, according to the present invention, the refrigerant liquid from the condenser is supercooled through the evaporator or the small heat exchanger and sent to the internal space of the motor to cool the motor. When the temperature of the condenser does not decrease, an excellent effect is obtained that the motor can be sufficiently cooled even when the refrigerator operates in the heat pump mode and the temperature of the condenser increases.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration example of a refrigerator including a motor cooling device according to the present invention.

FIG. 2 is a diagram illustrating a configuration example of supercooling a refrigerant liquid of the motor cooling device according to the present invention.

FIG. 3 is a diagram illustrating a configuration example of supercooling a refrigerant liquid of the motor cooling device according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Evaporator 2 Condenser 3 Multistage compressor 4 Economizer 5 Piping 6 Piping 7 Piping 8 Piping 9 Piping 10 Piping 11 Small heat exchanger 12 Pump 13 Piping

Claims (1)

[Claims] 1. A refrigerator motor cooling device for cooling a motor of an evaporator, a condenser, a multi-stage compressor, and a motor having a motor for driving the multi-stage compressor, wherein the condensate is generated in the condenser. Providing a refrigerant introduction path for introducing a refrigerant liquid into the internal space of the motor, supercooling the refrigerant liquid passing through the refrigerant introduction path through the evaporator or the small heat exchanger, sending the refrigerant liquid to the internal space of the motor, and A motor cooling device for a refrigerator, wherein the cooling liquid after cooling is returned to the economizer or the condenser.