JPS6091162A - Heat pump type air conditioner - 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 Field of the Invention The present invention relates to a heat pump type air conditioner and relates to an antifreeze coil for an outdoor heat exchanger in a cooling system.

Conventional configuration and its problems In conventional heating-only heat pump air conditioners, after defrosting, defrost water remains at the bottom of the outdoor heat exchanger, and when heating operation is resumed, the outdoor air conditioner acts as an evaporator. There was a problem that the bottom of the heat exchanger froze, resulting in extremely poor heat exchange. In order to solve this problem, conventional methods have been used to prevent freezing by flowing the condensate electrolyte obtained in the indoor heat exchanger, which acts as a condenser, to the bottom of the outdoor heat exchanger.

A conventional example will be explained with reference to FIG.

The figure is a refrigeration cycle diagram of a conventional heat pump air conditioner, where 1 is a compressor, 2 is a four-way valve, 3 is an indoor heat exchanger that acts as a condenser during heating, and 4 acts as an evaporator during heating. The outdoor heat exchangers are connected in an annular manner through refrigerant pipes 5 to form a refrigeration cycle. And indoor heat exchanger 3
A first pressure reducer 6 is connected in series between the and the outdoor heat exchanger 4.
, a second pressure reducer 7, and a check valve 8 in parallel with the second pressure reducer 7. At the bottom of the outdoor heat exchanger 4,
An antifreeze coil 9 is provided between the first pressure reducer 6 and the second pressure reducer 7.1. ing.

In the above configuration, the refrigerant flows as shown by the solid arrow during heating operation, and the refrigerant discharged from the compressor 1 is
The flow flows to the four-way valve 2, the indoor heat exchanger 3, and after the pressure is reduced to intermediate pressure by the first pressure reducer 6, a freezing device is installed at the bottom of the outdoor heat exchanger 4, which acts as an evaporator. Prevention coil 9
flows to.

Then, after flowing to the second pressure reducer 7 and being expanded, it is evaporated in the outdoor heat exchanger 4, and then returned to the compressor 1 via the four-way valve 2, and the cycle is repeated.

As described above, during heating operation, the condensed refrigerant always flows to the antifreeze coil 9, so the heating capacity of the indoor heat exchanger 3 to radiate heat indoors is limited to the lower part of the outdoor heat exchanger when the outside temperature is relatively high. There was a problem that the temperature decreased even when the temperature did not freeze.

Purpose of the Invention The present invention aims to improve heating capacity by preventing condensate refrigerant from flowing through the anti-freezing coil of an outdoor heat exchanger under normal conditions where the outside temperature is relatively high and no defrosting is performed. With the goal.

Structure of the Invention In order to achieve this object, the present invention provides a refrigerant storage tank between an indoor heat exchanger and an outdoor heat exchanger, and leads a refrigerant pipe from the upper part of the refrigerant storage tank to an antifreeze coil. Biki,
Furthermore, the structure is such that heat is exchanged around the refrigerant storage tank with the condensed liquid refrigerant obtained by the indoor heat exchanger.

Therefore, when the outside temperature is relatively high, that is, when the antifreeze coil is not needed, the refrigerant guided to the antifreeze coil
The area around the refrigerant storage tank exchanges heat with high-temperature condensed liquid refrigerant, so the inside of the refrigerant storage tank is separated into gas and liquid, and the gaseous refrigerant is guided from the top of the refrigerant storage tank to the antifreeze coil. Therefore, the amount of heat exchanged by the antifreeze coil is small.

Therefore, the indoor heat exchanger provides sufficient heating capacity. On the other hand, when the outside air temperature is low and the temperature of the condensed refrigerant is low, the refrigerant storage tank is filled with liquid refrigerant, so the liquid refrigerant flows to the antifreeze coil, and the bottom of the outdoor heat exchanger receives sufficient heat. be exchanged.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG.

Figure 2 is a refrigeration cycle diagram of a heat pump type air conditioner, where 11 is a compressor, 12 is a four-way valve, 13 is an indoor heat exchanger that acts as a condenser during heating, and 14 is a chamber that acts as an evaporator during heating. It is an external heat exchanger, and is connected in an annular manner through a refrigerant pipe 15 to form a refrigeration cycle. A first pressure reducer 16, a second pressure reducer 17, and a third pressure reducer 18 are connected in series between the indoor heat exchanger 13 and the outdoor heat exchanger 14. Furthermore, the second pressure reducer 1γ and the third pressure reducer 18
A first check valve 19 and a second check valve 2o are provided in parallel, respectively, in order to make it difficult for refrigerant to flow into the pressure reducer during cooling operation. A refrigerant storage tank 21 is provided between the first pressure reducer 16 and the second pressure reducer 17, in which a part of the refrigerant pipe 15 is tightly wound around the circumference. This refrigerant storage tank 21 is connected from the top to the second pressure reducer 17, and is also connected to one end of the antifreeze coil 22 provided at the bottom of the outdoor heat exchanger 14. Further, it is connected to the other side of the antifreeze coil 22 from the lower bottom, and the main pressure reducer 17 is connected to this connection point.

Next, the operation based on the above configuration will be described.

To make the effects easier to understand, we will explain them separately for normal heating operation, low outside temperature heating operation, and cooling operation.

First, the normal heating operation will be explained.

During normal heating operation, the refrigerant flows as shown by the solid arrow in the figure, and the refrigerant discharged from the compressor 11 is guided to the indoor heat exchanger 13 via the four-way valve 12. The refrigerant led from the indoor heat exchanger 13 is reduced in pressure to an intermediate pressure in the first pressure reducer 16, and then passes through the refrigerant pipe 15 tightly wound around the refrigerant storage tank 21 to the second pressure reducer. It will lead you to 17. The refrigerant guided through the second pressure reducer 17 is then introduced into the upper part of the refrigerant storage tank 21. At this time, refrigerant storage tank 2
The refrigerant in the refrigerant storage tank 2 undergoes heat exchange with the surroundings using a relatively high-temperature refrigerant (even the refrigerant saturation temperature in the refrigerant storage tank) led from the indoor heat exchanger 13.
The refrigerant in 1 is separated into gaseous and liquid. The gaseous refrigerant flows from the upper part of the storage tank 21 toward the antifreeze coil 22, and the liquid refrigerant flows through the third pressure reducer 18.
flows towards. Therefore, since the refrigerant flowing to the antifreeze coil 22 is gaseous, the amount of heat exchanged in the antifreeze coil 22 is very small.

The refrigerant led from the refrigerant storage tank 21 is completely expanded in the third pressure reducer 18, evaporated in the outdoor heat exchanger 14, and then returned to the compressor 11 via the four-way valve 12. form. In this way, during normal heating operation that does not require defrosting, only a small amount of condensed heat is exchanged in the anti-freeze coil, so the heating capacity is not reduced.

Next, a description will be given of heating when the outside temperature is low.

The flow of the refrigerant when the outside temperature is low for heating is exactly the same as during normal heating operation, but when the outside temperature is low, the condensation temperature in the indoor heat exchanger 13 is lower, so the flow of the refrigerant is Even if the pressure is reduced by the second pressure reducer 17, the condensation temperature is lower than the refrigerant saturation temperature, so the refrigerant in the refrigerant storage tank is always liquid. Therefore, since the refrigerant flowing from the upper part of the refrigerant storage tank 21 to the anti-freezing coil 22 is also liquid, the lower part of the outdoor heat exchanger 14, that is, the part that is almost frozen during unpacking, is heated by the anti-freezing coil 22. The thick liquid refrigerant in stock allows for sufficient heat exchange and prevents freezing.

Next, the cooling operation will be explained.

During cooling operation, the refrigerant flows as shown by the broken line arrow in the figure.The refrigerant discharged from the compressor 11 is led to the outdoor heat exchanger 14 via the four-way valve 12, where it is condensed and liquefied, and then passed through the second check valve. Then, it is divided into seven parts in the direction of the antifreeze coil 22 and the refrigerant storage tank 21. The refrigerant that has flowed to the antifreeze coil 22 is guided from the upper part of the refrigerant storage tank 21 and joins therewith. Furthermore, the refrigerant is decompressed and expanded from the upper part of the refrigerant storage tank 21 through the first check valve 19 in the first pressure reducer 16, and then evaporated in the indoor heat exchanger 13 to cool the indoor side. After that, a cycle is formed in which the air returns to the compressor 11 via the four-way valve 12. Therefore, there is no possibility that the refrigerant will evaporate in the refrigerant storage tank 21 during cooling operation and loss of heat of evaporation will occur.

Effects of the Invention As described above, according to the present invention, a refrigerant storage tank in which heat is exchanged with a refrigerant around which a condensate refrigerant flows is provided between an indoor heat exchanger and an outdoor heat exchanger, and a refrigerant pipe is connected to the refrigerant storage tank. The upper part of the refrigerant storage tank is guided to the antifreeze coil installed at the bottom of the outdoor heat exchanger. The refrigerant flows and can prevent the bottom of the outdoor heat exchanger from freezing. Furthermore, during normal heating operation that does not require defrosting, gas refrigerant flows through the anti-freeze coil, so there is less heat loss in the anti-freeze coil, and the indoor heat exchanger can provide sufficient heating capacity. be.

[Brief explanation of drawings]

FIG. 1 is a refrigeration cycle diagram of a conventional heat pump type air conditioner, and FIG. 2 is a refrigeration cycle diagram of a heat pump type air conditioner showing an embodiment of the present invention. 11...Compressor, 13...Indoor heat exchanger, 14...Outdoor heat exchanger, 21...Refrigerant storage tank, 22...Anti-freeze coil. Name of agent Patent attorney Toshio Nakao and 1 other person No. 1
Figure-Last day

Claims (1)

[Claims] It is configured by connecting a compressor, an indoor heat exchanger, an outdoor heat exchanger, etc. in an annular manner, and a refrigerant storage tank is provided between the indoor heat exchanger and the outdoor heat exchanger, and the refrigerant A heat pump type air conditioner, which connects the upper part of a storage tank to an anti-freeze coil provided at the bottom of the outdoor heat exchanger, and arranges a refrigerant pipe around the refrigerant storage tank through which condensed refrigerant flows.