JPS59189253A - Defroster of refrigeration cycle - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a defrosting device for a refrigeration cycle that defrosts a cooler with high-temperature refrigerant gas discharged from a compressor. The present invention relates to a defrosting device.

Next, a conventional defrosting device for a refrigeration cycle as described above will be described with reference to Figure Z showing an embodiment Z of the present invention.

In the figure 2, l is the compressor, 2 is the condenser, 3□3゜ is the cooler, 6 is the main liquid TS valve, 7 is the auxiliary solenoid valve, 8 is the differential pressure valve, 9
．． ．． 92 is a liquid solenoid valve; 10. ．． 102 is an expansion valve; 11.
I 11. is a check valve, I J + I J is an intake solenoid valve, 13. ．． 13. 14 is an electric valve for high-temperature refrigerant, and 14 is an accumulator, which are connected to each other by a refrigerant pipe to form a refrigeration cycle. Further, 4 is a type for driving the pressure machine and a motive force.

In the refrigeration cycle consisting of the above-mentioned valleys, during abnormal cooling operation, the refrigerant discharged from the compressor 1 becomes a condensate liquid in the condenser 2, passes through the main liquid type and the magnetic valve 6, and goes to the cooler side. Sent. At this time, the high temperature refrigerant gas solenoid valves ta, ta, g and the auxiliary solenoid valve 7 are closed. Therefore, the condensed refrigerant liquid flows through the liquid solenoid valves 9, , 92 and the expansion valve "t +
The pressure was reduced at 10 t, and then the cooler 3. , 3. The refrigerant is evaporated into refrigerant gas, which is sucked into the compressor 1 through the intake solenoid valve 121+1''2 and the accumulator 14.The flow of the refrigerant during this period is indicated by solid line arrows in the figure.

Next, during defrosting operation, a portion of the high-temperature refrigerant gas discharged from the compressor 1 is sent to the condenser 2, which will be explained as an example. By flowing through the refrigerant gas electromagnetic valve 1317 to the cooler 31, and defrosting it by removing the 1.
Condenses to become refrigerant liquid. At this time, the high temperature refrigerant gas solenoid valve 13. ? Although the main liquid solenoid valve 6 is closed, the auxiliary solenoid valve 7 is open, and the condensing pressure is appropriately adjusted by the action of the differential pressure valve 8. vL liquid solenoid valve9. Cooler 3. is also closed. The condensed refrigerant liquid passes through the check valve 11°, and then passes through the liquid solenoid valve 9. The pressure is reduced by the expansion valve 10°, and the cooler 3. It evaporates into refrigerant gas, and the suction solenoid valve 12. ya
As shown in FIG. 1, gas and liquid are separated in the accumulator 4 and sucked into the compressor 1.

8. The flow of the refrigerant during this period is indicated by the dashed arrow in the figure. The defrosting of the cooler 32 is also performed by the cooler 3.
As in case of cooler 3. The condensed refrigerant liquid is evaporated in the cooler 31, thereby forming a frozen cycle.

In the defrosting device for the refrigeration cycle as described above, the cooling load during defrosting operation is always smaller than the load during normal cooling operation9, and in the example shown in the figure, it is 1/2. Therefore, during defrosting operation, the compressor is operated in response to a small cooling load, so the suction pressure of the compressor decreases, which not only causes poor operating efficiency, but also prevents the refrigerant from evaporating. However, it had the disadvantage of causing a liquid back phenomenon. In addition, there were cases where the suction pressure exceeded the compressor's lower limit of use χ, causing the low pressure switch, which was a protection device, to operate. In order to prevent these problems, conventional defrosting devices such as those mentioned above have been limited to being applied only to multi-type refrigerators capable of low-load operation, and when defrosting, high-pressure and low-pressure side capacitors are used. suction pressure y117r
The equipment is complicated, as the
There was a problem in that the pumping efficiency deteriorated further.

At the beginning of this year, the above-mentioned problems and drawbacks can be easily solved by defrosting the refrigeration cycle by operating the compressor at a lower speed by lowering the rotation speed of the compressor drive motor during defrosting operation than during cooling operation. The purpose is to provide equipment.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

In the figure, reference numeral 5 denotes an inverter which is a control means attached to the motor 4 for driving the compressor, and the inverter 5 makes the number of rotations of the electric motor 40, that is, the rotation of the compressor 1 variable. 7. Cj6. Is there a configuration other than the above for this embodiment? Since the basic operation is the same as that of the conventional example, the explanation thereof will be omitted.

And, this example can be used to drive the compressor if the cooling load decreases during defrosting operation! By lowering the rotational speed of the motor 4 using the inverter 5, the cooling capacity of the compressor 1 can be adjusted to match the cooling load, and the suction pressure can be reduced. Since the operating speed of the compressor 1 can be continuously changed depending on the number of rotations of the electric motor 4, the most efficient conditions can be selected for operation. be able to.

The defrosting operation can be electrically synchronized, and it can be performed by sensing the temperature or pressure of the refrigerant in the case, so this defrosting operation has a wide range of applications. .

As explained above, the present invention provides a defrosting device for a refrigeration cycle that uses high-temperature refrigerant gas discharged from a compressor. Since the compressor is operated at a lower speed than the conventional defrosting device, it has a simple configuration and disadvantages such as the liquid back phenomenon of the conventional defrosting device and the stoppage due to a decrease in the suction pressure of the compressor. This has the effect that the compressor can be operated efficiently, stably and smoothly during defrosting operation.

[Brief explanation of the drawing]

The figure is a configuration explanatory diagram showing one embodiment of this tower. 1... Compressor, 2... Condenser, "+ + 32...
·Cooler. 4... Compressor driving electric motor, 5... Inverter (control means), 6... Main liquid solenoid valve, 9. +9. ...
Liquid solenoid valve. 10,. 10. °°゛Expansion valve 111, 111. ... Check valve, 13 + + t 32 ... Solenoid valve for high temperature refrigerant gas, 14 ... Accumulator. Agent: Great Elderly Monk (2 others) βl/3゜za 7

Claims (2)

[Claims] (1) In a defrosting device for a refrigeration cycle that melts frost adhering to a cooler with high-temperature refrigerant gas discharged from a compressor, a control means is provided to operate the compressor at a lower speed during defrosting operation than during cooling operation. A defrosting device for a refrigeration cycle, characterized in that it is installed in the electric motor. (2) According to claim 1, a part of the cooler of a refrigeration cycle composed of a compressor, a condenser, and a plurality of coolers is defrosted with high-temperature refrigerant gas discharged from the compressor. Defrost equipment for the refrigeration cycle described.