JPH09152195A - Refrigerating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to prevent the supercooling from falling short even where the piping between individual apparatuses is long. SOLUTION: This apparatus relates to a refrigerating apparatus of the separated type in which devices such as a compressor 5 and heat exchangers 6, 10 constitute a refrigeration cycle and these constituent devices are assigned respectively to an outdoor apparatus 2 and an indoor apparatus 3 connected by a piping 4 to each other. The liquid refrigerant pipe 13 of the piping 4 connecting the outdoor and indoor apparatuses is provided with a subcooler 20 at a position close to the indoor apparatus 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a separate type refrigerating apparatus including an outdoor unit, an indoor unit, and unit-to-unit piping connecting these units.

[0002]

2. Description of the Related Art A separation type refrigerating apparatus (air conditioner) is one in which an indoor unit inside a house and an outdoor unit are arranged outdoors, and both units are connected by unit piping.

In a general household air conditioner, since the length of the inter-unit pipe is several meters, the amount of refrigerant charged in the inter-unit pipe is very small. Therefore, since the amount of the refrigerant that increases in accordance with the length of the inter-unit pipe is small, the liquid refrigerant can be sufficiently stored in the accumulator, and there is little risk that the compressor will cause liquid compression when the compressor is started.

[0004]

However, in a separation type air conditioner for business use or building air conditioning, the installation distance between both units is often longer than that for household use, and the unit-to-unit piping (long The length of the pipe) is, for example, 3
The pressure loss may be as large as 0 m to 100 m, and the pressure loss is large.

Therefore, conventionally, when the separated type air conditioner is operated for cooling, an air-cooling type supercooling coil is incorporated and set in the refrigerant pipe in the outdoor unit. The refrigerant is supercooled (subcooled) through the refrigerant pipe in the outdoor unit.

However, when the length of the inter-unit pipe is long as described above, there is a problem that pressure loss of the pipe occurs and the pressure of the refrigerant decreases, and bubbles are generated in the refrigerant to cause insufficient subcooling. . Further, since the conventional air-cooling type coil for supercooling is incorporated in the outdoor unit and set, it needs to be specially designed and is not versatile.

It is an object of the present invention to solve the above problems and to provide a refrigerating apparatus capable of preventing insufficient supercooling even when the unit piping is long.

[0008]

According to a first aspect of the present invention, a refrigerating cycle is constituted by devices such as a compressor and a heat exchanger, and these devices are distributed and arranged in an outdoor unit and an indoor unit. In the separation type refrigeration system in which the indoor unit and the indoor unit are connected by the inter-unit pipe, the sub-cooler is arranged in the refrigerant liquid pipe portion of the inter-unit pipe located near the indoor unit, and the sub-cooler is the refrigerant. A pressure reducing valve for reducing the pressure of a part of the refrigerant from the liquid pipe portion, a heat exchanger for cooling the refrigerant passing through the refrigerant liquid pipe portion through the pressure-reduced refrigerant, and a refrigerant passing through the heat exchanger of the subcooler. And a pipe portion for guiding the unit to the refrigerant gas pipe portion of the inter-unit pipe.

In the first aspect of the present invention, during the cooling operation, the inter-unit pipe is long, so that the refrigerant passing through the inter-unit liquid pipe causes a pressure loss and a pressure drop causes insufficient supercooling to cause bubbles in the refrigerant. In order to prevent this, the refrigerant passing through the inter-unit pipe can be supercooled by the subcooler. In addition, when it is necessary to lengthen the inter-unit piping, the subcooler can be retrofitted to the indoor unit, so there is no need to incorporate it in the indoor unit itself.
Then, the refrigerant that has passed through the heat exchanger can be returned to the refrigerant gas pipe portion of the inter-unit pipe.

According to a second aspect of the present invention, a heat pump type refrigeration cycle capable of cooling and heating operations is constituted by devices such as a compressor, a four-way valve, and a heat exchanger, and these devices are distributed to an outdoor unit and an indoor unit. In the separated type refrigeration system in which the outdoor unit and the indoor unit are connected by the inter-unit piping, the first liquid acting on the refrigerant liquid pipe part of the inter-unit pipe located near the indoor unit during the cooling operation is placed. A second subcooler, which operates during heating operation, is arranged in the refrigerant liquid pipe portion of the inter-unit pipe located in the vicinity of the outdoor unit where the cooler is arranged.

According to the second aspect of the present invention, since the inter-unit pipe is long, the refrigerant passing through the inter-unit liquid pipe is prevented from pressure loss and insufficient cooling due to pressure drop, so that bubbles are not generated in the refrigerant. Therefore, during the cooling operation or the heating operation, the refrigerant passing through the inter-unit pipe can be supercooled by the subcooler. In addition, when it is necessary to lengthen the inter-unit piping, the subcooler can be retrofitted to the indoor unit and the outdoor unit, so there is no need to incorporate the subcooler in the indoor unit and the outdoor unit itself.

[0012]

Embodiments of the present invention will be described below with reference to the accompanying drawings. [First Embodiment] In FIG. 1, reference numeral 1 is a separation type refrigerating apparatus dedicated to cooling for business use, which includes an outdoor unit 2, an indoor unit 3, and a unit-to-unit piping 4 connecting both units 2 and 3. It is configured.

A compressor 5, an outdoor heat exchanger 6 and a fan 7 are built in the outdoor unit 2, and the fan 7 is rotated by a fan motor 8 to blow air to the outdoor heat exchanger 6. ing.

On the other hand, the indoor unit 3 includes a capillary tube 9 that operates during cooling operation and an indoor heat exchanger 10.
The fan 11 is built in, and the fan 11 is rotated by the fan motor 12 to blow air to the indoor heat exchanger 10.

The inter-unit piping 4 is the inter-unit liquid pipe 13
And an inter-unit gas pipe 14.

In FIGS. 1 and 2, the subcooler 20 is
It is arranged with respect to the inter-unit liquid pipe 13 in the vicinity of the indoor unit 3. The supercooler 20 is provided with a decompression valve 22 for decompressing a part of the refrigerant from the inter-unit liquid pipe 13 and a refrigerant for passing the decompressed refrigerant to cool the refrigerant passing through the inter-unit liquid pipe 13. Heat exchanger 24
And

One end 22a of the pressure reducing valve 22 is connected to a position near the indoor unit 3 of the inter-unit liquid pipe 13, and the other end 22b of the pressure reducing valve 22 is connected to the heat exchanger 24. The heat exchanger 24 has a substantially cylindrical shape and is of a double-tube type and is arranged concentrically around the inter-unit liquid pipe 13 near the indoor unit 3 and has a plurality of fins 30 for heat exchange. .

A part of the refrigerant from the inter-unit liquid pipe 13 passes through the pressure reducing valve 22, the other end 22b through the heat exchanger 24, and the inter-unit gas pipe 14 through the pipe 26.
Is to be led to.

Next, the operation of the refrigerating apparatus will be described.

This refrigerating apparatus is exclusively for cooling operation, and when the compressor 5 is operated, the refrigerant discharged from the compressor 5 is discharged between the outdoor heat exchanger 6 and the unit as shown by the solid arrow in FIG. The liquid pipe 13, the capillary tube 9, the indoor heat exchanger 10, and the inter-unit gas pipe 14 are circulated in this order. In this case, the outdoor heat exchanger 6 acts as a condenser, and the indoor heat exchanger 10 acts as an evaporator to remove heat from the indoor air to cool the room.

During such cooling operation, since the length A of the inter-unit pipe 4 is long, the inter-unit liquid pipe 13
The refrigerant passing through is supercooled by the supercooler 20 by the supercooler 20 in order to prevent the refrigerant from passing through the inter-unit liquid pipe 13 so that bubbles do not occur in the refrigerant due to insufficient cooling due to pressure loss and pressure drop. That is, a part of the refrigerant from the inter-unit liquid pipe 13 passes through the pressure reducing valve 22, passes from the other end 22b into the heat exchanger 24, and is guided to the inter-unit gas pipe 14 through the pipe 26. As a result, a part of the refrigerant from the inter-unit liquid pipe 13 is decompressed by the decompression valve 22 and the heat exchanger 2
Since 4 is cooled, this refrigerant can supercool the refrigerant passing through the inter-unit liquid pipe 13. [Second Embodiment] In FIG. 3, reference numeral 1 denotes a heat pump type separated refrigerating apparatus for cooling and heating, which includes an outdoor unit 2 and
The indoor unit 3 and the unit-to-unit piping 4 connecting both units 2 and 3 are configured.

The outdoor unit 2 contains a compressor 5, a four-way valve 5a, an outdoor heat exchanger 6, a fan 7, and a heating parallel circuit 53. The fan 7 is rotated by a fan motor 8. To blow air to the outdoor heat exchanger 6. The heating parallel circuit 53 includes a check valve 40a that is opened during cooling and closed during heating, and a capillary tube 40 that operates during heating. The four-way valve 5a is set to a solid line state during cooling and a broken line state during heating.

On the other hand, the indoor unit 3 has an indoor heat exchanger 10, a fan 11 and a parallel cooling circuit 55 built therein. The fan 11 is rotated by a fan motor 12 to blow air to the indoor heat exchanger 10. It is supposed to do. The cooling parallel circuit 55 includes a check valve 9a that is opened during heating and closed during cooling, and the capillary tube 9 that operates during cooling operation.

The inter-unit piping 4 is the inter-unit liquid pipe 13
And an inter-unit gas pipe 14.

The first subcooler 20 is arranged for the inter-unit liquid pipe 13 near the indoor unit 3. The supercooler 20 is provided with a decompression valve 22 for decompressing a part of the refrigerant from the inter-unit liquid pipe 13 and a refrigerant for passing the decompressed refrigerant to cool the refrigerant passing through the inter-unit liquid pipe 13. And a heat exchanger 24.

One end 22a of the pressure reducing valve 22 is connected to a position of the inter-unit liquid pipe 13 near the indoor unit 3, and the other end 22b of the pressure reducing valve 22 is connected to the heat exchanger 24. The heat exchanger 24 has a substantially cylindrical shape and is of a double-tube type and is arranged concentrically around the inter-unit liquid pipe 13 near the indoor unit 3 and has a plurality of fins 30 for heat exchange. .

A part of the refrigerant from the inter-unit liquid pipe 13 passes through the pressure reducing valve 22, the other end 22b through the heat exchanger 24, and the inter-unit gas pipe 14 through the pipe 26.
Is to be led to.

The second subcooler 120 is arranged with respect to the inter-unit liquid pipe 13 in the vicinity of the outdoor unit 2. This supercooler 120 is a pressure reducing valve 122 for reducing the pressure of a part of the refrigerant from the inter-unit liquid pipe 13.
And a heat exchanger 124 for cooling the refrigerant passing through the inter-unit liquid pipe 13 by passing the depressurized refrigerant.

One end 122a of the pressure reducing valve 122 is connected to the position of the inter-unit liquid pipe 13 near the outdoor unit 3, and the other end 122b of the pressure reducing valve 122 is connected to the heat exchanger 124 via the electric valve 123. ing. This heat exchanger 1
Reference numeral 24 has a structure similar to that of the heat exchanger 24, and is a substantially cylindrical and double-tube type liquid pipe 13 between units near the outdoor unit 2.
Are arranged concentrically around and have a plurality of fins 130 for heat exchange.

A portion of the refrigerant from the inter-unit liquid pipe 13 passes through the pressure reducing valve 122, the other end 122b through the heat exchanger 124, and is guided to the low pressure side suction side of the compressor 5 through the pipe 126. It is designed so that it can be used.

Moreover, the check valve 160 is arranged in the middle of the pipe 26 on the side of the subcooler 20 dedicated to cooling. In the check valve 160, since the pressure of the refrigerant on the inter-unit pipe 14 side becomes higher than the pressure of the refrigerant on the inter-unit pipe 13 side during the heating operation, the refrigerant flows from the inter-unit pipe 14 side to the first subcooler 20. It has a function of preventing backflow to the heat exchanger 24.

Next, the operation of the refrigerating apparatus will be described.

This refrigerating apparatus has the compressor 5 during the cooling operation.
When operated, the refrigerant discharged from the compressor 5
As indicated by the solid line arrow in FIG. 1, the four-way valve 5a, the outdoor heat exchanger 6, the check valve 40, the inter-unit liquid pipe 13, the capillary tube 9, the indoor heat exchanger 10, and the inter-unit gas pipe 14 are circulated in this order. It In this case, the outdoor heat exchanger 6 functions as a condenser, and the indoor heat exchanger 10 functions as an evaporator to remove heat from the indoor air to cool the room.

During such a cooling operation, since the inter-unit pipe 4 is long, pressure loss occurs in the refrigerant passing through the inter-unit liquid pipe 13 and the pressure drop causes insufficient cooling to cause bubbles in the refrigerant. In order to prevent this, the refrigerant passing through the inter-unit liquid pipe 13 is supercooled by the supercooler 20. That is, a part of the refrigerant from the inter-unit liquid pipe 13 passes through the pressure reducing valve 22, the other end portion 22 b passes through the heat exchanger 24, and the inter-unit gas pipe 14 through the pipe 26.
It is led to. As a result, a part of the refrigerant from the inter-unit liquid pipe 13 is decompressed and cooled by the pressure reducing valve 22 and further cooled by the heat exchanger 24, so that this refrigerant supercools the refrigerant passing through the inter-unit liquid pipe 13. can do.

Next, when the compressor 5 is operated during the heating operation, the refrigerant discharged from the compressor 5 has the four-way valve 5a, the inter-unit gas pipe 14 and the indoor heat exchange as shown by the broken line in FIG. The device 10, the check valve 9a, the inter-unit liquid pipe 13, the capillary tube 40, and the outdoor heat exchanger 6 are circulated in this order. In this case, the outdoor heat exchanger 6 acts as an evaporator and the indoor heat exchanger 10 acts as a condenser to heat the indoor air.

During such heating operation, since the inter-unit pipe 4 is long, pressure loss occurs in the refrigerant passing through the inter-unit liquid pipe 13 and the pressure drop causes insufficient supercooling to cause bubbles in the refrigerant. In order to prevent this, the supercooler 120 supercools the refrigerant passing through the inter-unit liquid pipe 13. That is, a part of the refrigerant from the inter-unit liquid pipe 13 passes through the pressure reducing valve 122, passes through the heat exchanger 124 from the other end 122b, and is guided to the low pressure suction side of the compressor 5 through the pipe 126. . As a result, a part of the refrigerant from the inter-unit liquid pipe 13 is decompressed by the pressure reducing valve 122 to be cooled, and further cooled by the heat exchanger 124.
This refrigerant can supercool the refrigerant passing through the inter-unit liquid pipe 13 on the outdoor unit 2 side.

In the refrigerating apparatus for cooling only shown in FIG. 1, the outdoor unit 2 is located lower than the indoor unit 3 and the height difference between the outdoor unit 2 and the indoor unit 3 exceeds, for example, 30 m. It is useful.

Further, in the refrigerating apparatus for cooling and heating operation of FIG. 3, the outdoor unit 2 is located below and the indoor unit 3 is
Can be supercooled even when is located above.

As the outdoor unit 2 and the indoor unit 3, standard units are used respectively, and a subcooler can be installed afterwards only on the indoor unit 3 side as required as in the first embodiment of FIG. Alternatively, if necessary, a subcooler can be retrofitted to both the indoor unit 3 and the outdoor unit 2 as in the second embodiment of FIG.

The present invention can be variously modified without departing from the scope of the claims.

For example, the subcooler may be set not only in the inter-unit liquid pipe 13 near the indoor unit but also in the liquid pipe inside the indoor unit. The present invention can also be applied to a multi-room air conditioner in which a plurality of indoor units are connected to one outdoor unit by the inter-unit piping 4.

[0042]

As described above, according to the first aspect of the invention, since the inter-unit pipe is long during the cooling operation, the refrigerant passing through the inter-unit liquid pipe is overcooled due to the pressure drop even if a pressure loss occurs. The refrigerant passing through the inter-unit piping can be cooled by the supercooler so that the shortage does not occur in the refrigerant. Then, the refrigerant that has passed through the subcooler can be returned to the refrigerant gas pipe portion of the inter-unit pipe,
With a simple structure, continuous cooling is possible.

According to the second aspect of the present invention, since the inter-unit pipe is long, the refrigerant passing through the inter-unit liquid pipe is prevented from pressure loss, resulting in insufficient cooling due to pressure drop, so that bubbles are not generated in the refrigerant. Therefore, during the cooling operation or the warming operation, the refrigerant passing through the inter-unit pipe can be supercooled by the subcooler. When it is necessary to lengthen the inter-unit piping, the subcooler can be retrofitted to the indoor unit and the outdoor unit, so there is no need to install the subcooler in the indoor unit and the outdoor unit itself.

[Brief description of the drawings]

FIG. 1 is a refrigerant circuit diagram showing a separate type refrigerating apparatus for cooling only according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing an example of a supercooler arranged in unit piping of the refrigerant circuit of FIG.

FIG. 3 is a refrigerant circuit diagram showing a separate type cooling / heating refrigerating apparatus according to a second embodiment of the present invention.

[Explanation of symbols]

 4 Unit-to-unit piping 5 Compressor 6 Outdoor heat exchanger 10 Indoor heat exchanger 13 Unit pipe liquid pipe (refrigerant liquid pipe part) 14 Unit pipe gas pipe (refrigerant gas pipe part) 20 Supercooler (first supercooler ) 22,122 Pressure reducing valve 24,124 Heat exchanger 120 Second subcooler

Claims (2)

[Claims] 1. A refrigeration cycle is configured by devices such as a compressor and a heat exchanger, and these devices are distributed and arranged in an outdoor unit and an indoor unit, and the outdoor unit and the indoor unit are separated by connecting pipes between the units. Type refrigerating apparatus, a subcooler is arranged in the refrigerant liquid pipe portion of the inter-unit pipe located near the indoor unit.
The pressure reducing valve for reducing the pressure of a part of the refrigerant from the refrigerant liquid pipe portion, the heat exchanger for cooling the refrigerant passing through the refrigerant liquid pipe portion through the reduced pressure refrigerant, and the heat exchanger of the supercooler A refrigerating apparatus comprising: a pipe portion that guides a refrigerant to a refrigerant gas pipe portion of a pipe between units. 2. A heat pump type refrigeration cycle capable of cooling and heating operations is constituted by devices such as a compressor, a four-way valve, and a heat exchanger, and these devices are distributed and arranged in an outdoor unit and an indoor unit, In a separation-type refrigeration system in which an outdoor unit and an indoor unit are connected by an inter-unit pipe, a refrigerant liquid pipe portion of an inter-unit pipe located near an indoor unit is cooled by a first liquid cooling pipe portion during cooling operation. A subcooler is arranged, and a second subcooler for cooling the refrigerant liquid pipe portion during heating operation is arranged in the refrigerant liquid pipe portion of the inter-unit pipe located near the outdoor unit. Refrigeration equipment to be.