JP2763579B2 - Air conditioning - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerant cycle of a cooling and heating apparatus, and more particularly, to a low outside air refrigerant cycle.

2. Description of the Related Art In recent years, it has become increasingly necessary for cooling and heating devices such as buildings and computer rooms to perform a cooling operation even at a low outside air temperature.

Hereinafter, an example of the above-described conventional cooling and heating device will be described with reference to the drawings. FIG. 2 is a refrigerant cycle diagram of a conventional air conditioner. In FIG. 2, 1 is a compressor,
2 is a four-way valve, 3 is a heat source side heat exchanger, 3a is a blower that blows air to the heat source side heat exchanger 3, 4 is a heating decompression device, and 5 is a passage for bypassing the heating decompression device 4 during cooling. Check valve, 6 is a cooling decompression device, 7 is a check valve that forms a passage that bypasses the cooling decompression device 6 during heating, 8 is a use side heat exchanger, 9 is an accumulator, and these are outdoor units. a, indoor unit b, respectively, connection pipe
They are linked by c and d to form a well-known refrigerant cycle.

In the cooling and heating apparatus configured as described above, when performing the cooling operation at a low outside air temperature (for example, 0 ° C.), the normal cooling operation is performed, the rotation speed of the blower 3a is reduced, and the cooling operation to the heat source side heat exchanger 3 is performed. The air volume is reduced.

However, in the above configuration, however, it is necessary to greatly reduce the rotation speed of the blower 3a and reduce the amount of blown air, and the motor specifications of the blower 3a become very complicated and cost increases. .

In addition, if the connection pipes c and d become longer even if the blowing amount is greatly reduced, the amount of refrigerant in the refrigerant cycle also increases, and damage to the compressor 1 due to liquid back to the compressor 1 at startup or during normal operation. In addition, there is a problem that the compressor 1 must always be operated even when the outside air temperature is low, so that energy is not saved.

The present invention has been made in view of the above problems, and provides a cooling and heating device capable of performing safe and energy-saving low outside air cooling operation with a simple configuration without operating a compressor and without controlling the rotation speed of a blower. .

Means for Solving the Problems In order to solve the above problems, the cooling and heating device of the present invention,
Compressor, four-way valve, heat source side heat exchanger, pressure reducing device and first
A heat source side refrigerant cycle in which auxiliary heat exchangers are connected in a ring, a second auxiliary heat exchanger formed integrally with the first auxiliary heat exchanger and exchanging heat, and a first refrigerant transfer device; A first outdoor unit that stops operation during cooling operation at an outside air temperature, an indoor unit that includes a use-side heat exchanger, a third auxiliary heat exchanger that exchanges heat with outside air, and a second refrigerant transfer device. A second outdoor unit that operates during a cooling operation at a low outside air temperature and stops operation during a cooling and heating operation other than the cooling operation at a low outside air temperature, and the second outdoor unit during the cooling operation at a low outside air temperature. An outdoor unit is connected to the indoor unit, and a switching valve is provided for connecting the first outdoor unit and the indoor unit during a cooling / heating operation other than a cooling operation at a low outdoor temperature.

Effect of the Invention According to the above configuration, the compressor is not operated during the cooling operation at a low outside air temperature (for example, 0 ° C.), the switching valve is operated, the third auxiliary heat exchanger is used, and the second auxiliary heat exchanger is used. By cutting off the heat exchanger and operating the utilization side refrigerant cycle, low outside air cooling operation without operating the compressor becomes possible.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows a refrigerant cycle of a cooling and heating apparatus according to an embodiment of the present invention. In FIG. 1, 11 is a compressor, 12 is a four-way valve, 13 is a heat source side heat exchanger, 13a is a blower that blows air to the heat source side heat exchanger 13, 14 is a decompression device for cooling, 15
Is a non-return valve for heating, 16 is a check valve for closing the decompression device for cooling 14 during heating, 17 is a check valve for closing the decompression device for heating 15 during cooling, and 18 is a first auxiliary heat exchanger. Are connected annularly to form a heat source side refrigerant cycle. Reference numeral 19 denotes a second auxiliary heat exchanger which is integrally formed so as to exchange heat with the first auxiliary heat exchanger 18. Reference numeral 20 denotes a first refrigerant transfer device of the heat source side refrigerant cycle, which has reversible characteristics in which the refrigerant flows in opposite directions during cooling and during heating.
It is stored in.

21a and 21b are electric switching valves, 22 is a third auxiliary heat exchanger, 2
Reference numeral 3 denotes a use-side heat exchanger. A refrigerant cycle in which the second auxiliary heat exchanger 19 and the use-side heat exchanger 23 are connected in an annular manner by the switching valves 21a and 21b, and a third auxiliary heat exchanger 22 and the use-side Heat exchanger
23 and the second refrigerant transport device 24 are switched to a refrigerant cycle in which they are connected in a ring.

Reference numeral 22a denotes a blower that blows air to the third auxiliary heat exchanger 22, and the third auxiliary heat exchanger 22, the blower 22a, and the second refrigerant transfer device 24 are housed in the second outdoor unit b, and use side heat exchange. The vessel 23 is housed in the indoor unit c and is connected to the outdoor units a and b by connection pipes d, e, f and g.

The operation of the cooling / heating device configured as described above will be described.

During a normal cooling operation in which the outside air temperature is high, the refrigerant cycle is indicated by a solid line in the figure. It liquefies, passes through a check valve 16, is depressurized by a cooling decompression device 14, evaporates in a first auxiliary heat exchanger 18, and circulates through a four-way valve 12 to a compressor 11. At this time, the second auxiliary heat exchanger 19 of the utilization side refrigerant cycle and the first auxiliary heat exchanger 18
Exchanges heat, the gas refrigerant in the use-side refrigerant cycle is cooled and liquefied, is sent to the use-side heat exchanger 23 through the connection pipe d, the switching valve 21b by the first refrigerant transfer device 20, and is absorbed and evaporated. It is gasified and circulated to the second auxiliary heat exchanger 19 through the connection pipe e and the switching valve 21a.

In the cooling operation when the outside air temperature is low (for example, 0 ° C.), the refrigerant cycle is indicated by a double line in the figure, and the operation of the heat source side refrigerant cycle is stopped (compressor 11, first refrigerant transport device 2).
0 and the blower 13a are stopped), the switching valves 21a and 21b are operated, and the blower 22a is operated to operate the third auxiliary heat exchanger 2
Form a utilization side refrigerant cycle that uses 2.

That is, depending on the outside air temperature, the refrigerant is transferred to the third auxiliary heat exchanger.
Liquid cooling at 22 and connection piping by the second refrigerant transfer device 24
f, switching valve 21b, use-side heat exchanger through a part of connection pipe d
23, and is absorbed, evaporated, gasified, and passed through a part of the connection pipe e, the switching valve 21a, and the connection pipe g.
Will circulate.

On the other hand, during the heating operation, the refrigerant cycle is indicated by a broken line in the drawing, and in the heat source side refrigerant cycle, the high-temperature and high-pressure refrigerant from the compressor 11 is sent from the four-way valve 12 to the first auxiliary heat exchanger 18 to radiate heat. Condensed and liquefied, decompressed by the heating decompression device 15 from the check valve 17, and absorbed and evaporated by the heat source side heat exchanger 13,
Circulating to compressor 11 through 12. At this time, the second auxiliary heat exchanger 19 of the use side refrigerant cycle and the first auxiliary heat exchanger 18 exchange heat, the refrigerant in the use side refrigerant cycle is heated and gasified, and the connection pipe e and the switching valve 21a are switched. Street use side heat exchanger 23
To be heated and liquefied, and the connection pipe d, the switching valve 21
It is sent to the first refrigerant transport device 20 through b and circulated to the second auxiliary heat exchanger 19.

As described above, according to the present embodiment, the compressor 11, the four-way valve 1
2, a heat-source-side refrigerant cycle in which the heat-source-side heat exchanger 13, the pressure reducing devices 14, 15 and the first auxiliary heat exchanger 18 are connected in a ring shape, and a heat exchange formed integrally with the first auxiliary heat exchanger 18. A first outdoor unit a for stopping the cooling operation at a low outside air temperature, and a use side heat exchanger 23. A unit c, a third auxiliary heat exchanger 22 for exchanging heat with the outside air, and a second refrigerant transport device
With 24, it operates during cooling operation at low outside temperature,
The second outdoor unit b, which stops the operation during the cooling / heating operation other than the cooling operation at the low outdoor temperature, and the second outdoor unit b and the indoor unit c during the cooling operation at the low outdoor temperature, A switching valve for connecting the first outdoor unit a and the indoor unit c during a cooling / heating operation other than the cooling operation at a temperature.
21a and 21b, during the cooling operation at a low outside air temperature, the third auxiliary heat exchanger and the second refrigerant transfer device can be used to operate the use side heat exchanger without operating the compressor of the heat source side refrigerant cycle. Since the cooling operation of the exchanger can be performed, energy can be efficiently saved, and the compressor can be prevented from being damaged by the liquid bag at the time of startup or during operation.

Effect of the Invention As described above, the present invention provides a heat source side refrigerant cycle in which a compressor, a four-way valve, a heat source side heat exchanger, a pressure reducing device and a first auxiliary heat exchanger are connected in a ring shape, A first outdoor unit including a second auxiliary heat exchanger formed integrally with the exchanger and exchanging heat, and a first refrigerant transfer device, wherein the first outdoor unit stops operation during cooling operation at a low outside air temperature; An indoor unit equipped with a heat exchanger, a third auxiliary heat exchanger for exchanging heat with the outside air, and a second refrigerant transfer device, which operate during a cooling operation at a low outside temperature, and perform a cooling operation at a low outside temperature A second outdoor unit that stops operation during a cooling / heating operation other than at a time, and connects the second outdoor unit and the indoor unit at a time of a cooling operation at a low outdoor temperature, except for a cooling operation at a low outdoor temperature. Connects the first outdoor unit and the indoor unit during cooling / heating operation Since the switching valve is provided, during the cooling operation at a low outside air temperature, the third auxiliary heat exchanger and the second refrigerant transfer device can be used without operating the compressor of the heat source side refrigerant cycle,
Since the cooling operation of the use side heat exchanger can be performed, energy can be efficiently saved, and the compressor can be prevented from being damaged by the liquid bag at the time of startup or during operation.

[Brief description of the drawings]

FIG. 1 is a refrigeration cycle diagram of a cooling and heating device according to an embodiment of the present invention, and FIG. 2 is a refrigeration cycle diagram of a cooling and heating device showing a conventional example. 11 ... compressor, 12 ... four-way valve, 13 ... heat source side heat exchanger,
14,15 …… Decompression device, 18 …… First auxiliary heat exchanger, 19 ……
2nd auxiliary heat exchanger, 20 ... 1st refrigerant conveyance apparatus, 21a, 21b
... switching valve, 22 ... third auxiliary heat exchanger, 23 ... use side heat exchanger, 24 ... second refrigerant transport device, a ... first outdoor unit, b ... second outdoor unit, c ... Indoor unit c.

Claims (1)

(57) [Claims] 1. A heat source side refrigerant cycle in which a compressor, a four-way valve, a heat source side heat exchanger, a pressure reducing device and a first auxiliary heat exchanger are connected in a ring shape, and formed integrally with the first auxiliary heat exchanger. A first auxiliary heat exchanger for performing heat exchange and a first refrigerant transfer device, wherein the first operation is stopped during a cooling operation at a low outside air temperature.
An outdoor unit, an indoor unit having a use-side heat exchanger, a third auxiliary heat exchanger for exchanging heat with outside air, and a second refrigerant transport device, which are operated during a cooling operation at a low outside air temperature; A second outdoor unit that stops operation during a cooling / heating operation other than a cooling operation at a low outside air temperature; and a second outdoor unit and the indoor unit that connect the second outdoor unit and the indoor unit during a cooling operation at a low outside air temperature. A switching valve for connecting the first outdoor unit and the indoor unit during a cooling / heating operation other than a cooling operation at a time.