JPH0638015B2 - Operation control device for refrigerator - Google Patents

Description

TECHNICAL FIELD The present invention relates to a refrigerator operation control device.

Configuration of Conventional Example and Its Problems Conventionally, refrigerator control that changes the operating frequency of the compressor determines the operating frequency of the compressor based on the difference between the refrigerator internal temperature and the set temperature. For temperature, run the compressor at high frequency,
When the inside temperature = set temperature, the compressor is operated at a low frequency, and when the inside temperature <set temperature, the compressor is turned off. For example, as shown in Fig. 1, when the difference between the set temperature and the in-chamber temperature is ± 1 ° C (set temperature zone), the compressor is operated at 30 Hz. The compressor is operated at 60 Hz until is higher than the set temperature by 5 ° C., and the compressor is operated at 90 Hz when the temperature is higher than the set temperature. In this control method, if the temperature inside the refrigerator equilibrates within the set temperature range, continuous operation at 30 Hz is performed.
This causes the compressor to rotate at a slower speed,
The sliding part is liable to be insufficiently supplied with oil, which causes a problem in operation.

SUMMARY OF THE INVENTION Therefore, the present invention is to eliminate the trouble of operation due to insufficient oil supply to the sliding portion of the compressor.

To achieve this object, the present invention provides a compressor that operates at a frequency lower than the commercial frequency by providing a timer that operates at the lowest frequency determined by the control means at a frequency higher than 0 Hz and at a frequency lower than the commercial frequency. If the operation of continues for a certain period of time, turn off the compressor.
It is designed to do F.

Description of Embodiments An embodiment of the present invention will be described below with reference to FIGS.

In FIG. 2, reference numeral 1 is an inside temperature detecting means for detecting the inside temperature, and 2 is a set temperature detecting means for detecting a set temperature. Reference numeral 3 denotes a defrost switch that detects when the temperature of the cooler reaches or exceeds a predetermined value during defrosting and terminates defrosting. Reference numeral 4 is a control means composed of a microcomputer, which has I ₁ , I ₂ , I ₃ and output terminals O ₁ , O ₂ . And the inside temperature detecting means 1 and the set temperature detecting means 2
The inputs of the compressor 5 are compared and the frequency of the compressor 5 is determined according to the magnitude of the temperature difference between the two.

Reference numeral 6 denotes an operation control means, which is connected to the output terminal O ₁ of the control means 4 and receives the frequency determined by the control means 4,
For example, a transistor inverter that operates the compressor 5 at that frequency. Reference numeral 7 denotes a timer, which operates during a time period of a frequency higher than 0 Hz, which is the lowest frequency determined by the control means 4 and lower than the commercial frequency (hereinafter referred to as the lowest frequency), and outputs an output after operating for a predetermined time. Defrosting start detection means 8 detects the amount of frost on the cooler, and outputs an output when the amount of frost reaches a certain amount. 9
Has a contact 9 'in relay is connected to the output terminal O ₁ of the control unit 4. The relay 9 if the output from the defrosting start detection means 8 and the control unit 4 is input from the input terminal I4, and ON by the output of the output terminal O ₁ of the control means 4, defrosting by energizing the heater 10 Is what starts.

The operation will be described below with reference to FIG. FIG. 3 is a flow chart of the entire refrigerator in this embodiment.

In FIG. 3, one step is the inside temperature detecting means 1
The temperature inside the refrigerator detected by is input from the input terminal I ₁ . Then, in step 2, the set temperature detected by the set temperature detecting means 2 is input from the input terminal I ₂ . Next, in 3 steps, the internal temperature input in 1 step and the set temperature input in 2 steps are compared. In 4 steps, it is judged whether the force is OFF or not. In 5 steps, the operating frequency of the compressor 5 is determined and output to the operation control means 6 through the output terminal O ₁ .

For example, as a general rule, the difference between the set temperature and the internal temperature is ± 1 ° C.
If it is (set temperature zone), the compressor is operated at 30 Hz, if it is below the set temperature zone, the compressor is turned off, and it is set to 60 Hz until the internal temperature is higher than the set temperature zone and 5 ° C. higher than the set temperature. The operating frequency is determined so that the compressor is operated at 90 Hz and the compressor is operated at 90 Hz above that. At this time, the operation control means 6 operates the compressor 5 at the determined frequency. Next, in 6 steps, it is judged whether or not the operating frequency determined and output by the control means 4 is the lowest frequency, and if it is the lowest frequency, the timer 7 is operated in 7 steps. Next, in step 8, it is judged whether or not the timer 7 has reached the set time, and if it is the set time, in step 9 the control means 4 outputs an operating frequency of 0 Hz from the output terminal O ₁ to the operation control means 6 and The operation control means 6 turns off the compressor 5. Then, it is memorized that it was forcibly turned off in 10 steps. 1 if not set time
Go to step 2. Next, in step 11, the timer 7 is cleared. Even if it is not the lowest frequency in 6 steps, the process proceeds to 11 steps. Next, at step 12, whether or not the defrosting start detecting means 8 has output is fetched from the input terminal I4 of the control means 4, and if there is an output, the operation proceeds to step 15, and if there is no output, the operation returns to step 1. Then, 1 step → 2 steps → 3 steps → 4 steps are performed to judge whether the forced OFF is made in 4 steps. If forced OFF, the difference between the internal temperature and the set temperature is 1 ° C or more in 13 steps. It is judged whether or not it is 1 ° C or higher, and the process returns to step 1 again. If the temperature rises above 1 ° C, the memory of forced OFF is reset in 14 steps and the frequency is output in 5 steps. In the 15th step, the control means 4 causes the operation control means 6 to output an operating frequency of 0 Hz from the output terminal O _1.
Is output from the output terminal O ₂ in 16 steps to turn on the relay 9 to energize the heater 10 to start defrosting. Next, in step 17, the defrosting end detection means 3
Input from the input terminal I3, and the defrosting end detection means 3
If there is no output, the same operation is repeated, and if there is an output, proceed to step 18 to turn off the relay 9 to stop energizing the heater 10 and finish defrosting. Then, return to step 1.

Therefore, by operating the timer 7 when the compressor 5 is operating at the lowest frequency, the compressor is turned off when the operation at the lowest frequency continues for a certain period of time.
Therefore, it is possible to eliminate the obstacle to the operation due to the insufficient oil supply to the sliding portion of the compressor during the operation at the lowest frequency determined by the control means 4 and lower than the commercial frequency.

EFFECTS OF THE INVENTION As is clear from the above description, the present invention operates the timer when the output from the control means has the lowest frequency, and when the operation of the compressor at the lowest frequency continues for a certain period of time, the compressor is operated. Since the operation control means for turning it off is provided, it is possible to eliminate the trouble of operation due to insufficient oil supply to the sliding portion of the compressor during low frequency operation.

[Brief description of drawings]

FIG. 1 is a diagram showing a conventional refrigerator control method based on a refrigerator temperature and a preset temperature, FIG. 2 is a block diagram showing a refrigerator operation control device of the present invention, and FIG. 3 is a flowchart. 1-internal temperature detecting means, 2-set temperature detecting means, 4
...... Control means, 6 ...... Operation control means, 7 ...... Timer.

Claims (1)

[Claims] Claim: What is claimed is: 1. An inside temperature detecting means for detecting the inside temperature,
Set temperature detecting means for detecting the set temperature of the inside temperature, control means for determining and sending the operating frequency of the compressor by input from the inside temperature detecting means and the set temperature detecting means, and the control means The operation frequency is lower than the commercial frequency, and the operation control means operates the compressor at the specified operation frequency, and the timer operates at a frequency higher than 0 Hz and at the lowest frequency determined by the control means and lower than the commercial frequency. The operation control device for the refrigerator, which controls to turn off the compressor when the operation of the compressor is continuously performed for a certain period of time.