Refrigerator with refrigerant recovery control

Patent metadata

Field	Value
Publication number	US-12222145-B2
Application number	US-202118020214-A
Country	US
Kind code	B2
Filing date	Jun 17, 2021
Priority date	Aug 19, 2020
Publication date	Feb 11, 2025
Grant date	Feb 11, 2025

Abstract

A method controls a refrigerator. The refrigerator includes a compressor that includes a piston and uses refrigerant as lubricant for the piston, and the method includes determining an end time point of a refrigerant recovery operation based on a driving input value of the compressor to thereby reducer abrasion of the piston and power consumption.

First claim

The invention claimed is:

1. A method for controlling a refrigerator, the refrigerator including a refrigerating room evaporator, a freezing room evaporator, a compressor configured to supply refrigerant to each of the refrigerating room evaporator and the freezing room evaporator and to use the refrigerant as a lubricant for a piston, and a refrigerant control valve configured to control flow of the refrigerant from the compressor to each of the refrigerating room evaporator and the freezing room evaporator, the method comprising:
determining whether a condition for performing a refrigerant recovery operation is satisfied, wherein the refrigerant recovery operation is an operation for causing the refrigerant in at least one of the refrigerating room evaporator or the freezing room evaporator to return to the compressor;
based on the condition of the refrigerant recovery operation being satisfied, performing the refrigerant recovery operation;
determining a first driving input value applied to the compressor at a first time point corresponding to a start time point of the refrigerant recovery operation;
determining a second driving input value applied to the compressor at a time point subsequent to the first time point during the refrigerant recovery operation;
determining a ratio of the second driving input value to the first driving input value; and
terminating the refrigerant recovery operation based on the ratio of the second driving input value to the first driving input value being less than a preset ratio.

2. The method of claim 1 , further comprising:
determining whether a minimum refrigerant recovery operation time period has elapsed from the start time point of the refrigerant recovery operation; and
comparing the first driving input value to the second driving input value based on the minimum refrigerant recovery operation time period having elapsed from the start time point of the refrigerant recovery operation,
wherein the minimum refrigerant recovery operation time period is defined as a minimum value of an operation time period of the compressor to reduce abrasion of the piston.

3. The method of claim 1 , wherein each of the first and second driving input values corresponds to a driving power value applied to the compressor, and
wherein the method further comprises:
detecting a driving voltage and a driving current that are applied to the compressor; and
determining the driving power value based on the detected driving voltage and the detected driving current.

4. The method of claim 1 , further comprising:
determining whether the ratio of the second driving input value to the first driving input value becomes less than the preset ratio before an elapse of a preset maximum refrigerant recovery operation time from the start time point of the refrigerant recovery operation; and
based on determining that the ratio of the second driving input value to the first driving input value does not become less than the preset ratio before the elapse of the preset maximum refrigerant recovery operation time, terminating the refrigerant recovery operation at a time point corresponding to the preset maximum refrigerant recovery operation time.

5. The method of claim 1 , wherein terminating the refrigerant recovery operation is performed at a first instance at which the ratio of the second driving input value to the first driving input value becomes less than the preset ratio during the refrigerant recovery operation.

6. The method of claim 1 , further comprising:
comparing the first driving input value to the second driving input value;
determining whether a predetermined abnormal operation occurs in the compressor; and
based on an occurrence of the predetermined abnormal operation, terminating the refrigerant recovery operation regardless of a result of comparing the first driving input value to the second driving input value.

7. The method of claim 1 , further comprising:
comparing the first driving input value to the second driving input value; and
storing, in a non-transitory memory, the first driving input value prior to comparing the first driving input value to the second driving input value.

8. The method of claim 1 , wherein a time interval between the start time point and an end time point of the refrigerant recovery operation is changed based on the first driving input value and the second driving input value of the compressor.

9. The method of claim 1 , further comprising:
performing a first cooling operation by the refrigerating room evaporator; and
after performing the first cooling operation, performing a second cooling operation by the freezing room evaporator,
wherein a pressure and a temperature of the refrigerating room evaporator are higher than a pressure and a temperature of the freezing room evaporator, respectively, and
wherein the refrigerant recovery operation is performed after performing the second cooling operation.

10. The method of claim 1 , wherein the refrigerant recovery operation comprises:
driving the compressor while the refrigerant control valve is closed to thereby cause the refrigerant in at least one of the refrigerating room evaporator or the freezing room evaporator to return to the compressor.

11. The method of claim 1 , wherein the refrigerant recovery operation comprises performing a continuous operation or an intermittent operation of the compressor.

12. A refrigerator, comprising:
a compressor configured to compress refrigerant, the compressor comprising a piston;
a condenser configured to condense the refrigerant compressed by the compressor;
a refrigerating room expansion valve and a freezing room expansion valve that are configured to decompress the refrigerant condensed by the compressor and to expand the refrigerant;
a refrigerating room evaporator configured to evaporate the refrigerant expanded by the refrigerating room expansion valve to thereby generate cold air;
a freezing room evaporator configured to evaporate the refrigerant expanded by the freezing room expansion valve to thereby generate cold air;
a refrigerant control valve configured to adjust flow of the refrigerant from the condenser toward each of the refrigerating room evaporator and the freezing room evaporator; and
a controller configured to control the compressor and the refrigerant control valve to thereby perform a refrigerant recovery operation for causing the refrigerant in at least one of the refrigerating room evaporator or the freezing room evaporator to return to the compressor,
wherein the controller is configured to:
determine whether a condition for performing the refrigerant recovery operation is satisfied,
based on the condition of the refrigerant recovery operation being satisfied, perform the refrigerant recovery operation,
determine a first driving input value applied to the compressor at a first time point corresponding to a start time point of the refrigerant recovery operation,
determine a second driving input value applied to the compressor at a time point subsequent to the first time point during the refrigerant recovery operation,
determine a ratio of the second driving input value to the first driving input value, and
terminate the refrigerant recovery operation based on the ratio of the second driving input value to the first driving input value being less than a preset ratio.

13. The refrigerator of claim 12 , wherein the controller is configured to compare the first driving input value to the second driving input value after driving the compressor for a minimum refrigerant recovery operation time period, and
wherein the minimum refrigerant recovery operation

Assignees

• Lg Electronics Inc

Inventors

• Lee Sangil
• Hu Jinseok
• Ahn Buhwan
• Shin Seonggu

Classifications

• 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

• F25B2500/19

  Calculation of parameters · CPC title

• F25D11/022

  with two or more evaporators · CPC title

• F25B2700/151

  of the compressor motor · CPC title

• F25B2600/2515

  Flow valves · CPC title