KR101533644B1 - Hotgas defrosting refrigerating cycle device - Google Patents

Abstract

A refrigeration cycle apparatus is disclosed. According to an embodiment of the present invention, there is provided a refrigeration cycle apparatus including: a compressor for compressing a refrigerant at a high temperature and a high pressure; A condenser connected to the compressor through a first main pipe, for condensing the high temperature and high pressure refrigerant of the compressor into a liquid phase; A first expansion valve connected to the condenser through a second main pipe to decompressively expand the high-pressure liquid refrigerant condensed in the condenser; A receiver installed on the second main pipe for supplying only the low-temperature and low-pressure liquid refrigerant to the first expansion valve; An evaporator in which the low-temperature and low-pressure liquid refrigerant passing through the expansion valve is vaporized through heat exchange; A third main pipe connecting the evaporator and the compressor; A second expansion valve installed on a connection pipe connecting the receiver and the condenser such that the condenser serves as an evaporator when the evaporator is defrosted; A defrost valve unit for supplying a high-temperature and high-pressure refrigerant supplied from the compressor to the evaporator through the third main pipe in the first main pipe for defrosting the evaporator; And a first bypass pipe branched from the third main pipe and bypassing a portion of the high-temperature high-pressure refrigerant supplied to the evaporator to the condenser when the pressure of the evaporator rises to a predetermined pressure or higher.

Description

HOT GAS DEFROSTING REFRIGERATING CYCLE DEVICE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerator using a refrigeration cycle, and more specifically, to a refrigeration cycle apparatus to which a defrostable hot gas defrosting system is applied without requiring a separate heater for the defrosting.

Generally, the refrigeration cycle apparatus generates cold air by heat exchange between the evaporation heat of the evaporator and the outdoor air temperature. At this time, the surface of the evaporator is frozen due to the difference between the evaporation heat and the outside air temperature. Not only hinders the heat exchanging action of the evaporator but also increases the flow resistance of the cold air by the blowing fan, thereby increasing the power consumption of the refrigeration system.

Therefore, in the conventional refrigeration system, when the implantation amount is excessively increased, a defrost heater provided at one side of the evaporator is periodically operated to recover the original function of the evaporator, thereby removing the defrosting. Which is described in detail in Document 1.

[Patent Document 1] Korean Published Patent Application No. 2007-0019153 (published on February 15, 2007)

In the meantime, the performance of the evaporator is varied depending on various kinds of conception conditions such as the type of the articles stored in the freezer compartment and the refrigerating compartment, the temperature and humidity of the outside air, and the number of times of opening and closing the freezing compartment and the refrigerating compartment. The defrosting operation is performed by periodically operating the defrosting heater according to a predetermined defrosting timing without considering the defrosting operation, resulting in a lot of energy efficiency problems.

Embodiments of the present invention are intended to provide a hot gas defrost refrigeration cycle device capable of suppressing a rise in temperature of a freezer due to short defrosting time.

Embodiments of the present invention are to provide a hot gas defrost refrigeration cycle device capable of preventing a pressure rise of an evaporator used as a condenser during a steady state.

 The objects of the present invention are not limited thereto, and other objects not mentioned can be clearly understood by those skilled in the art from the following description.

According to an aspect of the present invention, there is provided a compressor for compressing refrigerant at a high temperature and a high pressure; A condenser connected to the compressor through a first main pipe, for condensing the high temperature and high pressure refrigerant of the compressor into a liquid phase; A first expansion valve connected to the condenser through a second main pipe to decompressively expand the high-pressure liquid refrigerant condensed in the condenser; A receiver installed on the second main pipe for supplying only the low-temperature and low-pressure liquid refrigerant to the first expansion valve; An evaporator in which the low-temperature and low-pressure liquid refrigerant passing through the expansion valve is vaporized through heat exchange; A third main pipe connecting the evaporator and the compressor; A second expansion valve installed on a connection pipe connecting the receiver and the condenser such that the condenser serves as an evaporator when the evaporator is defrosted; A defrost valve unit for supplying a high-temperature and high-pressure refrigerant supplied from the compressor to the evaporator through the third main pipe in the first main pipe for defrosting the evaporator; And a first bypass pipe branched from the third main pipe and bypassing a part of the high-temperature high-pressure refrigerant supplied to the evaporator to the condenser when the pressure of the evaporator rises above a predetermined pressure I want to.

The second bypass pipe may further include a second bypass pipe for allowing the refrigerant discharged from the evaporator to flow through the second main pipe to the receiver without passing through the expansion valve when the evaporator is defrosted.

The apparatus may further include a third bypass pipe that bypasses the filter drier installed in the second main pipe between the evaporator and the receiver so that the refrigerant flowing from the evaporator to the receiver when the evaporator is dispensed rapidly flows have.

The refrigeration system further includes a direct pipe installed to flow the refrigerant from the evaporator to the receiver without passing through the expansion valve, the evaporator, and the filter drier installed in the second main pipe between the evaporator and the receiver can do.

In addition, the defrost valve unit may include a four-way valve connected to the first main pipe and the third main pipe in order to switch the flow of the refrigerant in the cooling mode or the defrost mode, To the condenser through the four-way valve and from the evaporator to the compressor through the four-way valve, and in the defrosting mode, the refrigerant flows from the compressor through the four-way valve to the evaporator and from the condenser And can be controlled to flow to the compressor through the four-way valve.

The control unit may control the compressor, the condenser, the first expansion valve, the evaporator, the second expansion valve, and the defrost valve unit to switch the defrosting mode to the defrosting mode for a predetermined time for defrosting the evaporator.

The controller may further include a meter installed in the condenser to measure a refrigerant pressure. When the refrigerant pressure of the measuring device installed in the condenser drops to 1.8 kg / cm 2 or less in the defrost mode, the fan motor installed in the condenser operates Evaporation is induced. When the refrigerant pressure rises to 1.8 kg / cm < 2 > or more, the operation of the fan motor can be stopped.

Embodiments of the present invention can suppress the high pressure rise of the evaporator in the defrost mode.

Embodiments of the present invention can reduce defrost time and increase the pure cooling mode operation time to save energy.

1 is a configuration diagram illustrating a refrigeration cycle apparatus according to an embodiment of the present invention.
2 is a block diagram showing a refrigeration cycle apparatus according to a modification of the present invention.

Hereinafter, a refrigeration cycle apparatus according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

1 is a view showing a refrigeration cycle apparatus to which a hot gas defrosting system according to an embodiment of the present invention is applied.

1, a refrigeration cycle apparatus 1 according to an embodiment of the present invention includes a compressor 100 for compressing a refrigerant at a high temperature and a high pressure, a defrost valve unit 700 for switching a flow of refrigerant in a forward or reverse direction, A condenser 200 for condensing high temperature and high pressure refrigerant into a liquid phase, a liquid receiver 400 for supplying only liquid phase refrigerant to the first expansion valve, a first expansion valve 300, 400, a filter-drier 420 for removing moisture and foreign substances from the refrigerant, a high-temperature and high-pressure liquid-phase refrigerant supplied to the unit cooler 500 is expanded to a low-pressure refrigerant by an alternating action A first expansion valve 300 for decompressively expanding the refrigerant so that evaporation can be easily performed, a unit cooler 300 for cooling the low-temperature and low-pressure liquid refrigerant passing through the first expansion valve 300 through heat exchange, ) 500, and in the defrost mode Accumulation is, it contains a second expansion valve 600 such that reduced pressure to expand the refrigerant to the evaporator roles, configurations other than the second expansion valve 600 may be continuously connected to the host (900).

The main pipe 900 includes a first main pipe 910 connecting the compressor 100 and the condenser 200, a second main pipe 920 connecting the condenser 200 and the first expansion valve 300, a unit cooler 500 And a third main pipe 930 connecting the compressor 100 with the third main pipe 930.

In the refrigeration cycle apparatus 1, the refrigerant repeatedly performs a low-temperature and low-pressure gas state, a high-temperature and high-pressure gaseous state, and a room-temperature and high-pressure liquid state, and the unit cooler 500 is cooled or the unit cooler 500 ). (Low-temperature low-pressure section) in which the refrigerant is in a low-temperature and low-pressure state in the cooling mode is a section from the first expansion valve 300 to the inlet of the compressor 100. The portion (high-temperature high-pressure portion) where the refrigerant is in a gaseous state at a high temperature and a high pressure is a section from the outlet of the compressor 100 to the condenser 200. The portion where the refrigerant is in a liquid state at normal temperature and high pressure (room temperature high-pressure portion) is a section from the condenser 200 to the first expansion valve 300. In the cooling mode, the coolant cools the unit cooler 500 through such a repetitive cycle. Of course, the unit cooler 500 may include an evaporator.

On the other hand, the refrigeration cycle apparatus 10 is provided with a control unit 10 for controlling the above components. The control unit 80 includes a first measuring unit 12 for measuring the pressure of the unit cooler 500, a second measuring unit 14 for measuring the pressure of the condenser 200, a temperature sensor 16 for measuring the temperature of the unit cooler 500, . ≪ / RTI >

The control unit 10 switches the defrost mode to the defrost mode for a predetermined time period for defrosting the unit cooler 500. [ For example, the controller 10 sets the defrost time to 5 minutes, mounts the temperature sensor 16 to the unit cooler 500, sets the defrost start temperature to 0 ° C and the defrost end temperature to 25 ° C, It is possible to control to end the defrosting mode when either one of the constant temperature and time is satisfied.

When the refrigerant pressure of the second measuring device 14 installed in the condenser 200 drops to 1.8 kg / cm 2 or less in the defrosting mode, the control unit 10 operates the fan motor 210 installed in the condenser 200 to evaporate And the operation of the fan motor 210 can be stopped when the refrigerant pressure rises to 1.8 kg / cm 2 or more.

On the other hand, the defrost valve unit 700 switches the refrigerant discharged from the compressor 100 to be circulated to the condenser 200 in the cooling mode and to be able to circulate to the unit cooler 500 in the defrosting mode . In this embodiment, the defrost valve unit 700 may be a four-way valve 710, and the first main pipe 910 and the third main pipe 930 are connected to the four-way valve 710. That is, when the four-way valve 710 is in the cooling mode, A-> B and D-> C are connected, and in the defrosting mode, A-> D and B-> C are connected. For reference, in the defrost mode, the condenser 200 is used as an evaporator, and the unit cooler 500 can be used as a condenser.

The refrigerant flows in the defrosting mode in the refrigeration cycle apparatus 10 from the compressor 100 to the first main pipe 910 to the four-way valve 710 (A-> D) to the third main pipe 930 to the unit cooler 500, The second bypass pipe 950 the second main pipe 920 the third bypass pipe 960 the receiver 400 the connection pipe 980 the second expansion valve 600 the condenser 200, A first main pipe 910, a four-way valve 710 (B-> C), a third main pipe 930, and a compressor 100.

Meanwhile, the first bypass pipe 940 branches from the third main pipe 930 and is connected to the condenser 200. In the defrosting mode, the first bypass pipe 940 is provided to bypass a portion of the high-temperature high-pressure refrigerant supplied to the unit cooler 500 to the condenser 200 when the pressure of the unit cooler 500 rises above a predetermined pressure do. That is, when the high pressure of the unit cooler 500 provided from the first measuring instrument 12 is raised to 5 kg / cm 2 or more in the defrosting mode, the controller 10 operates the electronic valve 944 installed in the first bypass pipe 940 Thereby bypassing the refrigerant to the outlet of the second expansion valve 600, that is, to the condenser 200. The high temperature and high pressure refrigerant supplied to the condenser 200 through the first bypass pipe 940 can promote the evaporation of the refrigerant while meeting with the refrigerant passing through the second expansion valve 600, Can be suppressed. A check valve 942 is installed in the first bypass pipe 940 so that the refrigerant flows in one direction.

The second bypass pipe 950 is installed in the defrost mode so that the refrigerant from the unit cooler 200 flows through the second main pipe 920 to the receiver 400 without passing through the first expansion valve 300 . A check valve 952 is provided in the second bypass pipe 950 so that the refrigerant flows in one direction only (in the evaporator to the second main pipe) only in the defrost mode.

The third bypass pipe 960 is connected to the second main pipe 920 between the unit cooler 500 and the receiver 400 so that the coolant flows quickly from the unit cooler 500 to the receiver 400 in the defrosting mode Respectively. A filter drier 420 is installed in the second main pipe 920. In the defrost mode, when the refrigerant flows from the unit cooler 500 to the condenser 200, do. Accordingly, in the present invention, the third bypass pipe 960 bypassing the filter drier 420 is installed on the second main pipe 920 so that the refrigerant flows smoothly to the condenser 200 in the defrost mode. The third bypass pipe 960 is provided with a check valve 962 so that the refrigerant flows in one direction (from the unit cooler to the condenser).

2 is a block diagram showing a refrigeration cycle apparatus according to a modification of the present invention.

The refrigeration cycle apparatus of FIG. 2 includes a compressor 100 for compressing refrigerant to a high temperature and a high pressure, a defrost valve unit 700 for switching the flow of the refrigerant in the normal direction or the reverse direction, a condenser for condensing the high- A liquid receiver 400 for supplying only the liquid refrigerant to the first expansion valve 400 and a second expansion valve 300 installed between the first expansion valve 300 and the receiver 400 to remove moisture and foreign substances from the refrigerant, A filter-drier 420 for expanding the refrigerant, a filter-drier 420 for expanding the refrigerant, a high-temperature and high-pressure liquid-phase refrigerant supplied to the unit cooler 500 into a low-pressure refrigerant by an alternating action, A first expansion valve 300, a unit cooler 500 in which the low-temperature low-pressure liquid refrigerant having passed through the first expansion valve 300 is vaporized through heat exchange, and a condenser 500 in the defrost mode, The refrigerant And a second expansion valve 600 for decompressing and expanding the refrigerant, and these configurations have the same operational effects as the configurations of Fig.

However, in this modified example, the defrost valve unit 700 switches the refrigerant discharged from the compressor 100 to be able to circulate to the condenser 200 in the cooling mode by using inexpensive solenoid valves without using the four-way valve, The mode is switched to the unit cooler 500 so as to be circulated. That is, the defrost valve unit 700 includes a first switching electromagnetic valve 722, a second switching electromagnetic valve 724, a third switching electromagnetic valve 726, and a fourth switching electromagnetic valve 728. The piping provided with the second switching electromagnetic valve 724 is branched from the first main piping 910 which is the front end where the first switching electromagnetic valve 722 is installed and connected to the third main piping 930 and the third switching electromagnetic valve 726 is installed The pipe is branched from the first main pipe 910, which is the rear end where the first conversion electromagnetic valve 722 is installed, and is connected to the third main pipe 930. The first switching electromagnetic valve 722 and the fourth switching electromagnetic valve 728 are opened in the cooling mode and the second switching electromagnetic valve 724 and the third switching electromagnetic valve 726 are opened in the defrosting mode.

In this modification, the direct piping 970 is installed so that the refrigerant from the unit cooler 200 flows into the receiver 400 without passing through the first expansion valve 300 and the filter drier 420 in the defrost mode. . The direct piping 970 can be regarded as directly connecting the second bypass piping 950 and the third bypass piping 960 shown in FIG.

As described above, the refrigeration cycle apparatus of the present invention has a remarkable effect that the defrost time can be shortened by rapid defrosting, and the pure operation time is increased to save energy.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

100: compressor 200: condenser
300: first expansion valve 400: receiver
500: unit cooler 600: second expansion valve
700: Defrost valve portion

Claims (7)

A hot gas defrost refrigeration cycle apparatus comprising:
A compressor for compressing the refrigerant at a high temperature and a high pressure;
A condenser connected to the compressor through a first main pipe, for condensing the high temperature and high pressure refrigerant of the compressor into a liquid phase;
A first expansion valve connected to the condenser through a second main pipe to decompressively expand the high-pressure liquid refrigerant condensed in the condenser;
A receiver installed on the second main pipe for supplying only the low-temperature and low-pressure liquid refrigerant to the first expansion valve;
An evaporator in which the low-temperature and low-pressure liquid refrigerant passing through the expansion valve is vaporized through heat exchange;
A third main pipe connecting the evaporator and the compressor;
A second expansion valve installed on a connection pipe connecting the receiver and the condenser such that the condenser serves as an evaporator when the evaporator is defrosted;
A defrost valve unit for supplying a high-temperature and high-pressure refrigerant supplied from the compressor to the evaporator through the third main pipe in the first main pipe for defrosting the evaporator; And
And a first bypass pipe branched from the third main pipe and bypassing part of the high-temperature high-pressure refrigerant supplied to the evaporator to the condenser when the pressure of the evaporator rises to a predetermined pressure or higher. Defrost refrigeration cycle unit. The method according to claim 1,
And a second bypass pipe for allowing the refrigerant discharged from the evaporator to flow to the receiver via the second main pipe without passing through the first expansion valve when the evaporator is in operation, Device. The method according to claim 1,
And a third bypass pipe bypassing the filter drier installed in the second main pipe between the evaporator and the receiver so that the refrigerant flowing from the evaporator to the receiver can flow quickly when the evaporator is in operation. A hot gas defrost refrigeration cycle unit. The method according to claim 1,
A direct pipe is installed so that the refrigerant exiting the evaporator flows through the first expansion valve and the filter drier installed in the second main pipe between the evaporator and the receiver when the evaporator is driven, And a hot gas defrost refrigeration cycle device. The method according to claim 1,
The defrost valve portion
And a four-way switching valve to which the first main pipe and the third main pipe are connected to switch the flow of the refrigerant in the cooling mode or the defrost mode,
Wherein the four-way valve allows the refrigerant to flow from the compressor to the condenser through the four-way valve and from the evaporator to the compressor through the four-way valve during the cooling mode, Is controlled to flow from the condenser to the compressor through the four-way selector valve and to the compressor through the four-way selector valve. The method according to claim 1,
And a control unit for controlling the compressor, the condenser, the first expansion valve, the evaporator, the second expansion valve, and the defrost valve unit, and switching the defrosting mode to the defrosting mode for a predetermined time for defrosting the evaporator Hot gas defrost refrigeration cycle unit. The method according to claim 6,
Further comprising a meter installed in the condenser for measuring a refrigerant pressure,
The control unit
In the defrost mode, when the refrigerant pressure of the measuring device installed in the condenser drops to 1.8 kg / cm 2 or less, the fan motor installed in the condenser is operated to induce evaporation. When the refrigerant pressure rises to 1.8 kg / And the hot gas defrost refrigeration cycle device.

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