JPS5926197Y2 - Refrigeration equipment - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a refrigeration system, and particularly relates to a refrigeration system that reliably defrosts an evaporator.

Generally, in this type of refrigeration system, when the evaporator is frosted, high-temperature, high-pressure discharge gas from the compressor is directly supplied to the evaporator to perform a defrosting operation.

This defrosting operation is stopped when the temperature of the refrigerant on the discharge side of the evaporator exceeds a predetermined value.

However, when the refrigeration system is operated continuously, the temperature of the refrigerant on the discharge side of the evaporator is also high in the summer and low in the winter.

Therefore, in conventional refrigeration equipment, defrosting operation is stopped when the temperature of the refrigerant on the discharge side of the evaporator exceeds the same predetermined value throughout the year, so the evaporator is not completely defrosted in the summer. There are disadvantages in that the defrosting operation is stopped even though there is no defrosting, and in the winter, the defrosting operation is continued even though the defrosting of the evaporator is completed.

This invention was made in order to eliminate the above-mentioned drawbacks of the conventional technology, and is designed to increase the detection operating temperature of the refrigerant discharged from the evaporator to stop defrosting operation in the summer, and lower it in the winter.

An embodiment of this invention will be described below with reference to the drawings.

FIG. 1 is a refrigerant system diagram of the refrigeration system according to this invention.

In Fig. 1, the refrigerant compressed by the compressor 1 is transferred to the condenser 2.
It is condensed and supplied to the expansion valve 4 via the main line electromagnetic valve 3.

The expansion valve 4 expands the supplied refrigerant and sends it to the evaporator 5.

The evaporator 5 evaporates the sent refrigerant and exchanges heat with the load, and then is temporarily stored in the accumulator 6 and returned to the compressor 1.

This refrigerant circulation path constitutes a freezing refrigerant system A.

The defrosting solenoid valve 7 supplies the refrigerant discharged from the compressor 1 directly to the evaporator 5 when the evaporator 5 is frosted, and constitutes a defrosting refrigerant line B.

The temperature detection device 8 detects the temperature of the refrigerant on the discharge side of the evaporator 5.

Next, the operation of the refrigeration/cooling system shown in FIG. 1 will be explained using FIG. 2.

FIG. 2 is a control circuit diagram of FIG. 1.

In FIG. 2, relay R1 is energized by a closed circuit of input terminal 9a→compressor drive relay R1→input terminal 9b, and compressor 1 is driven.

At this time, a closed circuit is formed from the input terminal 9a to the break contact 10b of the auxiliary relay R1o to the relay R3 of the main system path solenoid valve 3 to the input terminal 9b, and the main system path solenoid valve 3 opens. is formed.

Furthermore, at this time, the timer 11 is energized.

When timer 11 is energized and a predetermined period of time has elapsed, timer 1
1 is energized and instantaneously closes its make contact 11a.

Therefore, a closed circuit is formed from the input terminal 9a to the changeover switch 121 constituting the outside temperature detection device 12 to the connection terminal 12a to the temperature detection device 8, and the relay R7 is energized to activate the defrosting solenoid valve 7. Open.

Also, the auxiliary relay RIO is energized, and its make contact 10
A is closed to self-hold the auxiliary relay Rto, and its break contact 10b is opened to deenergize the relay R3.

Therefore, the freezing refrigerant line A is closed and the defrosting refrigerant line B is closed.
is configured to perform a defrosting operation to defrost the frost on the evaporator 5.

In this case, the operating temperature of the winter break contact 8A constituting the temperature detection device 8 is set to a low temperature, for example, 10
It opens when the temperature exceeds ℃.

Further, in the outside air temperature detection device 12, when the outside air becomes 15°C or lower, the changeover switch 121 is connected to the connection terminal 12a, and when the outside air becomes 15°C or higher, the changeover switch 121 is connected to the connection terminal 12b.

Therefore, when the frost on the evaporator 5 is defrosted and the temperature of the refrigerant discharged from the evaporator 5 exceeds 10°C, the winter break contact 8A
opens, and relay R7 and auxiliary relay RIO are deenergized.

Therefore, the defrosting refrigerant system B is closed, the freezing refrigerant system A is configured, and the refrigeration operation is performed again.

Next, in the case of summer, the outside air temperature detection device 12 detects that the outside air is 15°C.
After detecting the above, the changeover switch 121 is connected to the connection terminal 12b.

Therefore, when the timer 11 is energized in the same manner as described above, a closed circuit is formed from the input terminal 9a → the changeover switch 121 → the connection terminal 12b → the summer break contact 11a that constitutes the temperature detection device 8 → the input terminal 9b. defrost operation as described above.

In this case, the operating temperature of the summer break contact 8B constituting the temperature detection device 8 is set to a high temperature, for example, 20°C.
If it becomes more than that, it will be released.

Therefore, when the frost on the evaporator 5 is defrosted and the temperature of the refrigerant discharged from the evaporator 5 reaches 20°C or higher, the summer break contact 8
B opens, relay R7 and auxiliary relay Rt.

is deactivated.

Therefore, the refrigeration operation is performed again as described above.

This device is configured as described above, and takes advantage of the fact that the outside air temperature is high in the summer and low in the winter, and the detection operating temperature of the refrigerant discharged from the evaporator 5 is adjusted to stop defrosting operation in the summer. By increasing the temperature and lowering it in winter, the frost on the evaporator 5 can be effectively defrosted.

As described above, according to this invention, it is possible to effectively defrost the evaporator.

[Brief explanation of the drawing]

FIG. 1 is a refrigerant system diagram of a refrigeration system according to the present invention. FIG. 2 is a control circuit diagram of FIG. 1. In the figure, 1 is a compressor, 2 is a condenser, 3 is a main line solenoid valve, 4 is an expansion valve,
5 is an evaporator, 7 is a defrosting solenoid valve, 8 is a temperature detection device, 8
A is a break contact for winter, 8B is a break contact for summer, 12 is an outside temperature detection device, A is a freezing refrigerant system path, and B is a defrosting refrigerant system path.

Claims (1)

[Scope of utility model registration request] a compressor for compressing refrigerant; a condenser for condensing the refrigerant compressed by the compressor; an expansion valve for supplying and expanding the refrigerant condensed in the condenser via a main path solenoid valve; a refrigerant cooling system path consisting of an evaporator in which the refrigerant expanded by the valve is evaporated and then returned to the compressor; a defrost refrigerant system, a temperature detection device that detects the temperature of the refrigerant discharged from the evaporator and operates to close the defrost refrigerant system when the detected temperature exceeds the operating temperature; and a temperature detection device that detects the outside air temperature and detects the detected temperature. A refrigeration system characterized by comprising an outside air temperature detection device that increases the operating temperature of the temperature detection device if the detected temperature is high, and lowers the operating temperature of the temperature detection device if the detected temperature is low.