KR100271682B1 - Variable method for de-frost period in a refrigerator - Google Patents

Abstract

A method of varying a defrost cycle of a refrigerator to improve the cooling performance of the refrigerator by setting a defrost cycle of the refrigerator according to a defrost slope. The method of changing the defrost cycle of the refrigerator may include determining whether a defrost mode of the refrigerator has elapsed; determining whether the refrigerator is in defrost condition when the defrost mode has elapsed; Operating a defrost heater in a defrost inrush condition; Calculating a defrost slope by averaging derivatives with respect to the temperature change of the defrost sensor during operation of the defrost heater; Determining whether the temperature sensed by the defrost sensor is greater than or equal to a predetermined temperature; Resetting the next defrost cycle and the return temperature according to the defrost slope when the temperature detected by the defrost sensor is equal to or greater than a predetermined temperature; Completing the defrost upon reaching the return temperature. Therefore, by resetting the defrost cycle in response to the refrigerator defrost slope, it is possible to efficiently respond to the actual load of the refrigerator.

Description

Variable defrosting cycle of the refrigerator.

The present invention relates to a method of changing the defrost cycle of the refrigerator, and more particularly, to a method of changing the defrost cycle of the refrigerator to reset the defrost cycle of the refrigerator in response to a declination gradient that varies according to the amount of frost generated in the refrigerator.

In general, the conditions to be considered during the defrost cycle are: cumulative compressor operation time (6, 8, 10 hours), compressor operation rate (compressor operation cumulative operation time 2 hours), compressor operation time + compressor stop Time (more than 60 hours), cumulative door open time, outside temperature, errors of various sensors (D-sensor, F-sensor, outside temperature sensor) and door switch error.

The inrush condition to the defrost mode is a door that does not satisfy the above defrost inrush condition when the compressor operation rate is 2% or more when the defrost inrush condition is satisfied at 6, 8 and 10 hours of operation time of the compressor. When the open cumulative time is 10 minutes or more, when the outside temperature is 35 degrees or more and the compressor operation cumulative time is 6 hours or more, various types of errors occur and the defrost is started.

Then, if the operating time of the compressor + the stop time of the compressor is 60 hours or more, it immediately enters the defrost mode.

In addition, if the cumulative operation time of the compressor is 10 hours or more, the defrost mode is unconditionally entered. In the usual case, when the cumulative time of the compressor reaches 10 hours, the compressor is defrosted.

On the other hand, the defrost mode goes through the process of precooling, heater defrosting, rest period, fan delay, etc., Pre-COOL step is the step that the compressor, F-Fan is on for 50 minutes and time (50 minutes) Even if this time has not elapsed, the flick function is turned off if the temperature detected by the F-sensor is below -27 ° C.

In the defrosting step of the heater (HTR), the heater is turned off when the temperature detected by the D-sensor is 10 ° C. or more, and the limit time is 80 minutes. When the D-sensor is an error, the heater is driven on for 40 minutes.

The pause period is 4 minutes, and the compressor, F-fan and R-fan are all off, the fan delay time is 5 minutes and only the compressor is turned on.

During normal operation of the refrigerator, the temperature detected by the defrost detection sensor (D-sensor) of the refrigerator varies in response to the operation rates of the compressor, the F-fan, and the R-fan of the refrigerator.

However, when the outside temperature of the refrigerator is lowered, the operation rate of the refrigerator is shortened, and thus the defrosting cycle is lengthened. When defrosting is not performed for a long time, frost is attached to the evaporator to reduce the cooling performance of the refrigerator.

In addition, such a conventional refrigerator defrosting cycle does not actively change the defrosting cycle according to the amount of frost on the non-uniform sex, thereby reducing the cooling performance as described above.

The present invention was created to solve the above problems, by resetting the defrosting cycle corresponding to the defrost slope which changes according to the degree of frost generated in the refrigerator, defrost of the refrigerator to minimize the temperature change in the refrigerator The purpose is to provide a variable period method.

1 is a configuration diagram of a defrosting cycle variable method of the refrigerator according to the present invention;

2 is a flowchart illustrating the present invention.

3 and 4 are graphs for explaining the present invention.

<Description of the symbols for the main parts of the drawings>

10 ... R-sensor 20 ... F-sensor

30 ... D-sensor 40 ... door detector

50 ... Microcomputer 60 ... R fan drive

70 ... R fan 80 ... F fan drive

90 ... F Fan 100 ... Compressor Drive

110 Compressor 120 Defrost Heater Drive

130 ... Defrost Heater

According to another aspect of the present invention, there is provided a method of changing a defrost cycle of a refrigerator, including: determining whether a defrost mode of a refrigerator has elapsed; Determining whether the refrigerator enters a defrosting condition when the defrost mode has elapsed; Operating a defrost heater in a defrost inrush condition; Calculating a defrost slope by averaging derivatives with respect to the temperature change of the defrost sensor during operation of the defrost heater; Determining whether the temperature sensed by the defrost sensor is greater than or equal to a predetermined temperature; Resetting the next defrost cycle and the return temperature according to the defrost slope when the temperature detected by the defrost sensor is equal to or greater than a predetermined temperature; And completing the defrost upon reaching the return temperature.

According to a feature of the present invention configured as described above, the method of varying the defrosting cycle of the refrigerator according to the present invention, by changing the defrosting cycle corresponding to the defrosting slope that changes according to the degree of frost generated in the refrigerator, it is possible to change the temperature change in the refrigerator It can be minimized.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1, the R-sensor 10, the F-sensor 20, the D-sensor 30, the door detector 40, the microcomputer 50, and the R- The fan driver 60, the R fan 70, the F fan driver 80, the F fan 90, the compressor driver 100, the compressor 110, the defrost heater driver 120, and the defrost heater 130 are included. do.

In this configuration, the R-sensor 10 senses the refrigerator compartment temperature (generally, the DC value of the voltage value) of the refrigerator and applies it to the A / D (Analog to Digital) port of the microcomputer 50 to be described later.

The F-sensor 20 detects a freezer temperature (generally, a DC level voltage value) of the refrigerator and applies it to an A / D (Analog to Digital) port of the microcomputer 50 to be described later.

The defrost detection sensor is applied to the A / D (Analog to Digital) port of the microcomputer 50, which will be described later, of the defrost temperature detected by the D-sensor 30 (generally, DC voltage level).

The door detector 40 detects whether the refrigerator door opening has accumulated for a predetermined time, for example, 30 seconds or more, and outputs a door open / close detection signal to the microcomputer 50.

In addition, the microcomputer 50 independently controls the F fan, the R fan 90, 70 and the compressor 110 to be described later based on the appropriate temperature of the detected refrigerator which is applied to each A / D port and digitally converted. When the defrosting condition is reached, the defrosting heater 130 is driven to remove frost attached to the evaporator.

The R fan driver 60 outputs a predetermined drive signal to the R fan 70 under the control of the microcomputer 50 using a drive element, a relay, and the like. The R fan 70 is a fan for a refrigerating chamber. Driven based on the drive signal from the fan drive unit 60, the cold air around the evaporator is discharged to the refrigerating chamber.

The F fan driver 80 outputs a predetermined drive signal to the F fan 90 under the control of the microcomputer 50 using a drive element, a relay, and the like, and the F fan 90 is a fan for a freezer compartment. And driven based on a drive signal from the F fan drive unit 80 to discharge cold air around the evaporator to the freezer compartment.

The compressor driving unit 100 outputs a predetermined driving signal to the compressor 110 under the control of the microcomputer 50 using a driving element, a relay, and the like.

The defrost heater driver 120 outputs a predetermined driving signal to the defrost heater 130 under the control of the microcomputer 50, and the defrost heater 130 is a heater for removing frost attached to the evaporator and is mounted on the evaporator. The heat is generated based on the drive signal from the defrost heater driver 120 to melt and remove the frost attached to the evaporator.

Next, a detailed description will be given with reference to a flowchart of FIG. 2 attached to an operation process of a method of varying a defrost cycle of a refrigerator according to a preferred embodiment of the present invention including the above-described configuration unit.

First, when the amount of frost generated in the refrigerator is increased, the defrosting time is lengthened to remove the frost, and thus the load condition corresponding to the operation of the refrigerator can be known.

That is, the defrost slope is <defrost detection temperature> / <defrost time> referring to FIG. 3, and the load of the refrigerator can be predicted according to the defrost slope detected at 0 ° C. or less.

Therefore, the longer the defrosting time, the shorter the next defrosting cycle, and the higher the defrosting return temperature, thus eliminating frost residue.

Accordingly, the microcomputer determines whether the defrost mode of the refrigerator has elapsed (step 150). If the microcomputer does not pass, the initial defrost cycle is set.

When the defrost mode has elapsed, it is determined whether the defrosting condition is in step 170. If the defrosting condition is not present, the refrigerator performs normal operation (step 180) and checks the accumulated operation time of the compressor (step 190).

In the case of the defrost inrush condition, the defrost heater is operated (step 200). At this time, the defrost slope is calculated by averaging the derivative value of the temperature change amount of the defrost detection sensor with respect to the defrost time.

According to the experiments of the present inventors, if the next defrost cycle and the return temperature are set according to the graph shown in FIG. 4, the more optimal defrost cycle and the return temperature can be determined.

On the other hand, if the temperature detected by the defrost detection sensor is determined to be 0 ° C or more (step 220) or more, and performing the defrost by resetting the next defrost cycle and return temperature (step 230) according to the defrost slope calculated in the above-described step (step 230). Defrost is completed when the return temperature is reached (step 240).

In the method of changing the defrosting cycle of the refrigerator according to the present invention, by resetting the defrosting cycle corresponding to the defrosting slope that changes according to the degree of frost generated in the refrigerator, the cooling efficiency of the refrigerator can be increased and the temperature change in the refrigerator can be minimized. Will be.

Claims (1)

Determining whether the defrost mode of the refrigerator has elapsed; Determining whether the refrigerator enters a defrosting condition when the defrost mode has elapsed; Operating the defrost heater under the defrost inrush condition; Calculating a defrost slope by averaging derivatives with respect to the temperature change amount of the defrost sensor during operation of the defrost heater; Determining whether the temperature detected by the defrost detection sensor is greater than or equal to a predetermined temperature; Resetting a next defrost cycle and return temperature according to the defrost slope when the temperature detected by the defrost detection sensor is equal to or greater than a predetermined temperature; The defrost cycle variable method of the refrigerator characterized in that it comprises the step of completing the defrost upon reaching the return temperature.