JPS6045348B2 - Refrigerator operating circuit - Google Patents

Description

[Detailed Description of the Invention] The refrigerator operation circuit includes an abnormality stop circuit that detects an abnormality in the cooling operation and stops the operation of the refrigerator when the abnormality continues for a required period of time. In addition to the abnormal stop circuit, a defrost circuit is provided, and in the conventional system, the abnormal stop circuit and the defrost circuit are operationally independent of each other.

Therefore, even after the compressor operation is stopped due to the operation of the abnormal stop circuit, the defrost timer of the defrost circuit continues to operate, and defrost starts when the set time has elapsed. There was a drawback that the temperature inside the refrigerator room, which had been rising due to the stoppage, would further rise.

The present invention aims to provide an operating circuit for a refrigerator that eliminates the above-mentioned drawbacks by providing a defrost circuit and a disconnection circuit that simultaneously interrupts the defrost circuit when the refrigerator stops operating due to an abnormal stop circuit. DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the accompanying drawings, which are examples. FIG. 1 shows a first embodiment in which a defrosting-dedicated heater 1 and a drain pan heater 2 are used as the defrosting heat source, 3 is a compressor motor, and 4 is a fan motor for blowing cold air.

A is an abnormality stop circuit that detects an abnormality in the cooling operation and stops the operation of the compressor motor 3 and fan motor 4 when the abnormality continues for a required period of time, and 5 is a low pressure switch.
In abnormal stop circuit A, thermal overload 6,
An abnormality in the cooling operation in each case is detected by the high voltage switch 7, inner thermal relay 8, etc., and if the abnormality continues for a time exceeding the operation setting time of the alarm delay relay 9,
The time-limit normally closed contact 9a of the alarm delay relay 9 is opened to demagnetize the electromagnetic switch 10, and the contact 10a is opened to stop the compressor motor 3 and fan motor 4.

Further, the normally open contact 9b is closed for a limited time to turn on the alarm indicator light to notify of an abnormality. Note that G is a driving indicator light. B is a defrost circuit which has a defrost timer 12 for setting a defrost time and operates to defrost a cooler (not shown).

This defrost circuit B is constructed by connecting a defrost heater relay 13 and a drain pan heater relay 14 to switching output terminals 12a and 12b' of a defrost timer 12, and 15 is a defrost indicator light. c is a defrost cutoff circuit that operates to cut off the defrost circuit B at the same time as the compressor and fan are stopped by the abnormal stop circuit A, and connects the time-limited normally closed contact 9c of the alarm delay relay 9 to It is constructed by being inserted in series on the power supply line of the defrost circuit B.

Therefore, the alarm delay relay 9 operates, and at the same time the power supply to the compressor motor 3 and the fan motor 4 is stopped, the time-limited normally closed contact 9c is also opened, the power supply to the defrost circuit B is stopped, and the defrost heater Relay 13 and drain pan heater relay 14 are demagnetized and their respective contacts 13
a and 14a are opened, and the defrost heater 1 and drain pan heater 2 are no longer energized. 1
A manual operation switch 6 is used to open and close the power supply to the operation circuit. After an abnormal stop, this manual operation switch 16 is opened to inspect and repair the abnormality detection circuit, and then the manual operation switch is turned off. 16 is closed again and normal operation resumes.

FIG. 2 shows another embodiment in which high-temperature refrigerant gas discharged from a compressor is used as the defrost heat source.

The feature of this embodiment is that the defrost timer 12
and a liquid line solenoid valve relay 19 that is controlled on and off by the switching output of the defrost timer 12.
A defrost circuit B is constituted by a defrost liquid line solenoid valve relay 20 and a three-way solenoid valve relay 21 during defrost, and an alarm delay relay 9 constituting an abnormal stop circuit A is connected to the power supply line of this defrost circuit B. By intervening and connecting the time-limited normally closed contacts 9c in series, the defrost and disconnection circuit C is constructed. In FIG. 2, the same or similar reference numbers as in FIG. 1 indicate the same components. As described above, the operating circuit for a refrigerator according to the present invention is characterized in that it includes a circuit that cuts off the defrost circuit at the same time as the compressor and the fan are stopped by the abnormal stop circuit. If the stops abnormally,
The defrost circuit is also immediately disconnected, which has the effect of completely preventing a temperature rise due to defrost when the cooling operation is abnormally stopped, and smoother operation of the refrigerator can be achieved.

[Brief explanation of the drawing]

FIG. 1 shows one embodiment of the operating circuit according to the present invention, and FIG. 2 shows another embodiment. In the diagram, 1...defrost heater, 2...
Drain pan heater, 3... Compressor motor, 4...
...Fan motor, 6...Thermal overload, 7...High pressure switch, 8...
Inner thermal relay, 9...Alarm delay relay,
10... Electromagnetic switch, 11... Alarm indicator light, 12... Defrost timer, 13... Defrost heater relay, 14... Drain pan heater, 15... ...Defrost indicator light, 16...
・Manual operation switch, 17...Fuse, 18
・・・・・・Crankcase heater, 19・・・・・・
Relay for liquid line solenoid valve, 20... Relay for defrost liquid line solenoid valve, 20... Relay for defrost three-way solenoid valve, A... Abnormal stop circuit, B...
...Defrost circuit, C...Defrost circuit disconnected.

Claims (1)

[Claims] 1. In a refrigerator operation circuit comprising an abnormal stop circuit that detects an abnormality in cooling operation and stops the operation of the compressor when the abnormality continues for a required time, and a defrost circuit having a defrost timer, the abnormal stop circuit An operating circuit for a refrigerator, comprising a defrost cutoff circuit that operates to cut off the defrost circuit when the compressor is stopped.