JPH10339482A - Heat transferring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate a pressure difference of refrigerant between a main heat exchanger and a pressure reducing heat exchanger in a primary side circuit and then improve COP. SOLUTION: There is provided a primary side circuit 101 having a pressurizing heat exchanger 5 and a pressure reducing heat exchanger 7. The primary side circuit 101 and a secondary side circuit are connected to each other in such a way that they may be heat exchanged through a main heat exchanger 3, the pressurizing heat exchanger 5 and the pressure reducing heat exchanger 7. In the primary side circuit 101, the pressure reducing heat exchanger 7 and the main heat exchanger 3 are connected in series in such a way that the primary side refrigerant may flow while being evaporated in the order of the pressure reducing heat exchanger 7 and the main heat exchanger 3. As the primary side refrigerant, R407C of non-pyrolytic mixture refrigerant is used as thermal medium of which the temperature is increased as its heat is absorbed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat transfer device which can be used as a refrigerant circuit of an air conditioner, and more particularly to a heat transfer device for heating and cooling a refrigerant in a refrigerant circuit to obtain a driving force for circulation of the refrigerant. The present invention relates to the improvement of the apparatus described above.

[0002]

2. Description of the Related Art Conventionally, as a refrigerant circuit provided in an air conditioner, for example, as disclosed in Japanese Patent Application Laid-Open No. 63-180022, the refrigerant circuit heats and cools the refrigerant so as to circulate the refrigerant. 2. Description of the Related Art A heat transfer device that obtains a driving force is known.

[0003] This heat transfer device is constructed by sequentially connecting a heater, a condenser and a tank via a refrigerant pipe.
The tank is arranged at a position higher than the heater, and the heater and the tank are connected via a pressure equalizing pipe provided with an on-off valve.

With such a configuration, during indoor heating operation, the on-off valve is first closed, and the gas refrigerant heated by the heater is condensed and liquefied by the condenser. To be collected. After that, the on-off valve is opened, and the pressure of the heater and the tank is equalized by the pressure equalizing pipe, so that the liquid refrigerant is returned from the tank located at a position higher than the heater to the heater. By repeating such an operation, circulation of the refrigerant is enabled.

However, in such a configuration, when gas refrigerant is introduced into the tank from the condenser, the pressure in the tank increases, and there is a possibility that a good refrigerant circulation operation may not be performed. For this reason, it is necessary to keep the refrigerant in a supercooled state in the condenser so that the gas refrigerant does not flow out of the condenser, and it has been difficult to apply the refrigerant to a large-scale system or a long piping system.

[0006] In order to solve these problems, the inventors of the present invention provide a driving refrigerant circuit capable of switching between a pressurizing operation and a depressurizing operation for a tank storing a liquid refrigerant. Proposes a heat transfer device that improves the refrigerant circulation by pushing out the liquid refrigerant in the tank to the main refrigerant circuit while recovering the liquid refrigerant in the main refrigerant circuit to the tank by decompression operation. 8-1744751).

More specifically, as shown in FIG.
(x1) is provided with a pair of tanks (t1, t2) storing liquid refrigerant, while a compressor (a), a driving pressurized heat exchanger (b), a pressure reducing mechanism (c), and a driving A driving refrigerant circuit (x2) including a decompression heat exchanger (d) in order is provided. The refrigerant in the drive refrigerant circuit (x2) passes through the drive heat exchangers (b, d) and the main refrigerant circuit (x2).
Heat exchange is possible with the refrigerant of 1), and a single refrigerant such as R22 is used. This drive refrigerant circuit (x2)
Then, the gas refrigerant discharged from the compressor (a) exchanges heat with the refrigerant in the main refrigerant circuit (x1) in the pressurized heat exchanger (b) and condenses. This refrigerant is depressurized by the decompression mechanism (c),
In the decompression heat exchanger (d), heat exchange is performed with the refrigerant in the main refrigerant circuit (x1) to evaporate. Thus, in the main refrigerant circuit (x1), a high pressure is generated by the refrigerant heating operation in the pressurized heat exchanger (b), while a low pressure is generated by the refrigerant cooling operation in the decompressed heat exchanger (d). Then, this high pressure is applied to one tank (t1)
And the low pressure is supplied to the other tank (t2). That is, by simultaneously extruding the liquid refrigerant from one tank (t1) and recovering the liquid refrigerant to the other tank (t2), the circulation operation of the refrigerant in the main refrigerant circuit (x1) is obtained. I have to.

[0008]

However, the above-described structure has the following problems, and by overcoming these problems, it becomes possible to increase the efficiency of this type of apparatus. .

As shown in FIG. 6, in the above configuration, in the driving refrigerant circuit (x2), the reduced-pressure heat exchanger (d) is connected in parallel with the main heat exchanger (f). The main heat exchanger
(f) is a heat exchanger for transmitting hot or cold heat generated in the driving refrigerant circuit (x2) to the main refrigerant circuit (x1). That is, the main heat exchanger (f) is, for the main refrigerant circuit (x1),
This is a heat exchanger for absorbing hot or cold heat from the driving refrigerant circuit (x2) as a heat source.

In the cooling operation, the refrigerant in the main refrigerant circuit (x1) evaporates in the indoor heat exchanger (e), while the main heat exchanger (f)
Condensed. The main refrigerant circuit is also used in the vacuum heat exchanger (d).
The refrigerant of (x1) condenses. In contrast, the drive refrigerant circuit
The refrigerant of (x2) evaporates in the main heat exchanger (f) and also evaporates in the reduced pressure heat exchanger (d).

By the way, in order to generate a driving force for circulating the refrigerant in the main refrigerant circuit (x1), the pressure of the refrigerant in the decompression heat exchanger (d) is changed from the pressure of the refrigerant in the main heat exchanger (f). Also need to be lower. Therefore, it is necessary to maintain the refrigerant temperature of the decompression heat exchanger (d) lower than the refrigerant temperature of the main heat exchanger (f).

Therefore, in the driving refrigerant circuit (x2), the refrigerant temperature in the decompression heat exchanger (d) must be lower than that in the main heat exchanger (f). Therefore, after all, the refrigerant pressure in the decompression heat exchanger (d) in the driving refrigerant circuit (x2) is
It is necessary to maintain the refrigerant pressure lower than that in the main heat exchanger (f).

As a result, the pressure of the refrigerant sucked into the compressor (a) becomes lower than the evaporation pressure in the main heat exchanger (f),
The load on the compressor (a) was increasing. Therefore, it was difficult to say that the COP (coefficient of performance) of the air conditioner was sufficiently high.

The present invention has been made in view of the above point, and an object of the present invention is to provide a refrigerant circuit between a main heat exchanger (f) and a reduced-pressure heat exchanger (d) in a driving circuit. It is to eliminate the pressure difference and improve the COP.

[0015]

In order to achieve the above object, the present invention uses a heat medium whose temperature rises in accordance with heat absorption in a primary circuit, and uses a heat exchanger for reducing pressure from a main heat exchanger (3). The heat exchangers (3, 7) are connected in series so that the heat medium flows in the order of the heat exchanger (7).

Specifically, the means adopted by the invention of claim 1 is a primary circuit (101) in which the primary heat medium circulates.
And a secondary circuit (102) through which the secondary refrigerant circulates,
In the primary circuit (101), heat is transferred from the heat medium transfer means (1), the heat source side heat exchanger (4), and the secondary refrigerant to generate a low pressure in the secondary circuit (102). A decompression heat exchanger (7),
Main heat exchanger for exchanging heat between primary side heat medium and secondary side refrigerant
The secondary circuit (102) is connected between the main heat exchanger (3) and the indoor heat exchangers (8, 8,...). (49) and a utilization side circuit (102a) in which a refrigerant circulates through a main gas pipe (53) for heat transfer, and a main liquid pipe (48, 49).
A tank (21, 22) connected to the tank (21, 22); a pressurizing means (5) for pressurizing the tank (21, 22) to push refrigerant to the use side circuit (102a); and the tank (21, 22). ) To the user side circuit (102a)
The heat transfer device for recovering the refrigerant from the pressure reducing heat exchanger (7) is connected, and a driving force generating circuit (102b) for generating a driving force for circulating the refrigerant of the use side circuit (102a). The primary heat medium is a heat medium having a characteristic that the temperature increases in accordance with heat absorption, and the primary heat medium is supplied from the pressure reducing heat exchanger (7) to the main heat exchanger during cooling operation.
In the primary side circuit (101), the depressurizing heat exchanger (7) and the main heat exchanger are arranged so that heat flows while absorbing heat in the order of (3).
And (3) are connected in series.

According to the above-mentioned invention specifying matter, the secondary circuit (10
In 2), the pressurizing means (5) pressurizes the tanks (21, 22). As a result, the liquid refrigerant is pushed out of the tanks (21, 22). On the other hand, a low pressure is generated in the pressure reducing heat exchanger (7), and the pressure in the tanks (21, 22) is reduced. As a result, a driving force for circulating the secondary refrigerant is generated by the pushing operation and the suction operation of the refrigerant in the tanks (21, 22), and the secondary refrigerant circulates.

On the other hand, in the primary circuit (101), during the cooling operation, the heat medium discharged from the heat medium conveying means (1) is supplied from the pressure reducing heat exchanger (7) to the main heat exchanger (1). In the order of 3), it circulates while removing heat from the secondary refrigerant. As a result, the heat medium flows through the pressure reducing heat exchanger (7) and the main heat exchanger (3) in this order while increasing the temperature. Therefore, the decompression heat exchanger
The temperature of the heat medium in (7) becomes lower than the temperature of the heat medium in the main heat exchanger (3).

Therefore, the pressure of the secondary refrigerant in the pressure reducing heat exchanger (7) is maintained at a lower pressure than the pressure of the secondary refrigerant in the main heat exchanger (3), and the secondary circuit ( The circulation of the secondary refrigerant of 102) is performed favorably. Since the pressure of the heat medium sucked by the heat medium conveying means (1) of the primary circuit (101) is equal to the pressure of the heat medium in the main heat exchanger (3), it is possible to prevent a decrease in COP. .

According to a second aspect of the present invention, in the heat transfer device according to the first aspect, the primary heat medium is
A primary side refrigerant that undergoes a phase change in the primary side circuit (101),
The heat medium conveying means is constituted by a compressor (1), while the pressurizing means is constituted by a pressurizing heat exchanger (5) for heating the secondary refrigerant with the primary refrigerant. The circuit (101) includes a primary-side refrigerant discharged from the compressor (1) and a heat-source-side heat exchanger.
(4) and condensed in the pressurizing heat exchanger (5), decompressed by the decompressing mechanism (11), and circulated while evaporating from the depressurizing heat exchanger (7) to the main heat exchanger (3). The configuration is such that a closed circuit is configured to perform circulation returning to the compressor (1).

According to the above-mentioned specific features of the invention, an air conditioner or the like as a so-called cooling only machine can be obtained with a specific configuration.

According to a third aspect of the present invention, in the heat transfer device of the first aspect, the primary heat medium is
A primary side refrigerant that undergoes a phase change in the primary side circuit (101),
The heating medium transport means is constituted by a compressor (1), while the pressurizing means is constituted by a pressurizing heat exchanger (5) for heating the secondary refrigerant with the primary refrigerant. (101) is provided with a four-way switching valve (2) connected to the discharge side pipe and the suction side pipe of the compressor (1). After the primary-side refrigerant discharged from the compressor (1) passes through the four-way switching valve (2), the heat-source-side heat exchanger
(4) and condensed in the pressurizing heat exchanger (5), decompressed by the decompressing mechanism (11), and circulated while evaporating from the depressurizing heat exchanger (7) to the main heat exchanger (3). While circulating through the four-way switching valve (2) and returning to the compressor (1), during the heating operation, the primary refrigerant discharged from the compressor (1) is discharged by the four-way switching valve ( After passing through 2), it is condensed in the main heat exchanger (3) and the pressurizing heat exchanger (5), and decompressed by the decompression mechanism (11).
It is configured to carry out circulation by evaporating in the heat exchanger for pressure reduction (7) and the heat exchanger on the heat source side (4), passing through the four-way switching valve (2) and returning to the compressor (1). It is.

According to the above-mentioned specific features of the invention, a so-called heat pump type air conditioner or the like which can be reversibly operated with a specific configuration can be obtained.

According to a fourth aspect of the present invention, in the heat transfer device of the second aspect, the primary refrigerant is a non-azeotropic mixed refrigerant. Things.

According to a fifth aspect of the present invention, in the heat transfer apparatus of the fourth aspect, the primary refrigerant is R
407C.

According to the fourth and fifth aspects of the invention, it is possible to obtain a refrigerant having a characteristic that the temperature rises in accordance with heat absorption by a specific configuration.

[0027]

Embodiments of the present invention will be described below with reference to the drawings.

-Configuration of Air Conditioner (100)-As shown in FIG. 1, the air conditioner (10
0) is provided with a primary circuit (101) and a secondary circuit (102), and heat transfer between the primary circuit (101) and the secondary circuit (102) allows indoor air to be transferred. It is an air conditioner that performs air conditioning.

First, the secondary circuit (102) will be described, and then the primary circuit (101) which is a feature of the present invention will be described.

The secondary circuit (102) is connected to the main heat exchanger (3)
Secondary heat exchanger (32), secondary evaporator of pressurized heat exchanger (5)
(52), the secondary-side condenser (72) of the pressure-reducing heat exchanger (7), the first main tank (21), the second main tank (22), and the sub-tank (2
3), a plurality of second expansion valves (14, 14, ...) arranged in the room, a plurality of indoor heat exchangers (8, 8, ...), and a second four-way switching valve (25). . The main heat exchanger (3), the second expansion valves (14, 14, ...) and the indoor heat exchangers (8, 8, ...) constitute a use side circuit (102a) in the present invention. . The secondary evaporator (5
2) The secondary condenser (72) and each tank (21,22,23)
A driving force generation circuit (102b) for generating a driving force for circulating the secondary refrigerant is configured.

The main heat exchanger (3) is a heat exchanger for transmitting the hot or cold heat generated in the primary circuit (101) to the secondary circuit (102). Heat exchanger for pressurization (5) and heat exchanger for decompression
(7) heats or cools the refrigerant (secondary refrigerant) of the secondary circuit (102) by the refrigerant (primary refrigerant) of the primary circuit (101), and circulates the secondary refrigerant. Is a heat exchanger that generates the driving force of the heat exchanger.

More specifically, the lower end of the secondary heat exchange part (32) of the main heat exchanger (3) is connected to the second heat exchange part (32) via the main liquid pipe (48).
It is connected to a four-way switching valve (25). The upper end of the secondary heat exchange part (32) of the main heat exchanger (3) is connected to each indoor heat exchanger (8, 8,...) Via a main gas pipe (53). Each second expansion valve (14, 14, ...) connected to the indoor heat exchanger (8, 8, ...)
The main liquid pipe (49) is connected to the second four-way switching valve (25).

A gas supply pipe (41) is connected to the upper end of the secondary evaporator (52) of the heat exchanger (5) for pressurization. This gas supply pipe (41) is branched into three branch pipes (41a to 41c),
Each is individually connected to the upper end of each main tank (21, 22) and sub tank (23). Each of these branch pipes (41a to 41c)
Are the first to third tank pressurizing solenoid valves (SV-P1 to SV-P
3) is provided. On the other hand, pressurizing heat exchanger (5)
A liquid recovery pipe (42) is connected to the lower end of the secondary evaporator (52). The liquid recovery pipe (42) is connected to the lower end of the sub tank (23). The liquid recovery pipe (42) has a fourth check valve (C) that allows only the outflow of refrigerant from the sub tank (23).
V4) is provided. Each main tank (21,22)
Is arranged at a position lower than the pressure reducing heat exchanger (7). The sub-tank ((23) is arranged at a position higher than the pressurizing heat exchanger (5).

On the other hand, the secondary side condensing part of the heat exchanger for decompression (7)
A gas recovery pipe (43) is connected to the upper end of (72).
This gas recovery pipe (43) is also branched into three branch pipes (43a to 43c), each of which is connected to each of the branch pipes (41a to 41c) of the gas supply pipe (41), thereby each main tank (43). 21,22) and the upper end of the sub-tank (23). These branch pipes (43a to 43c) have first to third tank pressure reducing solenoid valves (S
V-V1 to SV-V3) are provided. In addition, a liquid pipe (47) is provided at the lower end of the secondary side condensation section (72) of the decompression heat exchanger (7).
Is connected. This liquid pipe (47) has two branch pipes (4
7a, 47b), each of which is individually connected to the lower end of the main tank (21, 22). These branch pipes (4
7a, 47b) include a tenth check valve (CV10) and an eleventh check valve (CV1) that allow only the recovery of refrigerant to the main tanks (21, 22).
1) is provided for each.

The second four-way switching valve (25) is a second expansion valve in the room.
A main liquid pipe (49) extending from (14, 14, ...) and a liquid supply pipe (44).
And a main liquid pipe (48) connected to the lower end of the secondary heat exchange section (32) of the main heat exchanger (3), and a liquid pipe (46). The second four-way switching valve (25) connects the main liquid pipe (49) and the liquid supply pipe (44) during the cooling operation, and
(48) and the liquid pipe (46), the main liquid pipe (49) and the liquid pipe (46) are connected during the heating operation, and the liquid supply pipe (44) and the main liquid pipe (48) are connected. Connect.

Next, the primary circuit (101) will be described.

The primary circuit (101) includes a compressor (1), a first four-way switching valve (2), an outdoor heat exchanger (4), and a pressurizing heat exchanger (5).
, A first expansion valve (11), a pressure reducing heat exchanger (7), and a main heat exchanger (3). The main circuit (103) and the auxiliary circuits (104, 104a, 105, 106) are connected in order. It has.

The main circuit (103) is provided with a solenoid valve and a check valve at predetermined positions. That is, the outdoor heat exchanger
Only the refrigerant flow from the outdoor heat exchanger (4) to the primary side condenser (51) is provided between (4) and the primary side condenser (51) of the pressurizing heat exchanger (5). An allowable second check valve (CV2) is provided, and the primary side evaporator (71) of the pressure reducing heat exchanger (7) and the main heat exchanger (3)
Between the primary evaporator (7) and the primary heat exchanger (31).
An eighth check valve (CV8) that allows only the refrigerant flow from 1) to the primary side heat exchange section (31) is provided.

The auxiliary circuit (104) is a circuit connecting the first four-way switching valve (2) and the primary heat exchanger (31) of the main heat exchanger (3).

The auxiliary circuit (104a) has one end connected to the auxiliary circuit (1).
04) and the other end of the second check valve (CV) of the main circuit (103).
2) and the pressurizing heat exchanger (5). The auxiliary circuit (104a) is provided with a third check valve (CV3) that allows only the refrigerant flow from the auxiliary circuit (104) side to the pressurizing heat exchanger (5) side.

The auxiliary circuit (105) has one end connected between the main heat exchanger (3) of the main circuit (103) and the eighth check valve (CV8),
The other end is connected between the pressurizing heat exchanger (5) and the first expansion valve (11). The auxiliary circuit (105) has a ninth circuit that allows only the refrigerant flow from the main heat exchanger (3) side to the first expansion valve (11) side.
A check valve (CV9) and a first solenoid valve (SV1) are provided.

The auxiliary circuit (106) has one end connected between the pressure reducing heat exchanger (7) of the main circuit (103) and the eighth check valve (CV8), and the other end connected to the outdoor heat exchanger (CV8). 4) and the second check valve (CV2). The auxiliary circuit (106) is provided with a first check valve (CV1) that allows only the refrigerant flow from the pressure reducing heat exchanger (7) side to the outdoor heat exchanger (4) side.

Thus, in the primary side circuit (101),
Primary evaporator (71) and main heat exchanger of decompression heat exchanger (7)
The primary heat exchange section (31) of (3) is connected in series.

The primary circuit (101) is filled with a refrigerant having a characteristic of increasing the temperature in accordance with heat absorption as a primary refrigerant. In this embodiment, specifically, R407C which is a non-azeotropic mixed refrigerant is filled.

-Operation of air conditioner (100)-Next, the operation of the air conditioner (100) is described in the refrigerant circuit (101, 10).
2) The operation will be described based on the circulation operation of the refrigerant inside.

(Cooling operation) First, the cooling operation will be described. During the cooling operation, each four-way switching valve (2, 25) is set on the broken line side in the figure. Pressurized solenoid valve for first main tank (21)
(SV-P1), pressure reducing solenoid valve (SV-V2) of the second main tank (22)
, And the pressure reducing solenoid valve (SV-V3) of the sub tank (23) is closed. On the other hand, the pressure reducing solenoid valve (SV-V
1) The pressurized solenoid valve (SV-P2) of the second main tank (22) and the pressurized solenoid valve (SV-P3) of the sub tank (23) are opened.

In this state, in the primary circuit (101), the high-temperature and high-pressure gas refrigerant discharged from the compressor (1) is supplied to the outdoor heat exchanger ( In 4), heat exchange is performed with outside air to condense. Thereafter, the refrigerant heats the secondary refrigerant in the pressurizing heat exchanger (5). The refrigerant flowing out of the pressurizing heat exchanger (5) is depressurized by the first expansion valve (11), and then flows into the depressurizing heat exchanger (7). This refrigerant partially evaporates in the primary evaporator (71) of the pressure reducing heat exchanger (7) to cool the secondary refrigerant. The refrigerant that has flowed out of the pressure-reducing heat exchanger (7) evaporates in the main heat exchanger (3) and gives cold heat to the secondary-side refrigerant. In other words, heat is taken from the secondary refrigerant to evaporate. The primary-side refrigerant flowing out of the main heat exchanger (3) passes through the first four-way switching valve (2), and then enters the compressor.
Inhaled in (1). Then, the refrigerant is discharged again from the compressor (1), and the above-described circulation operation is repeated.

Next, a description will be given of a change in the state of the primary-side refrigerant in the circulation operation.

As shown in the Mollier diagram of FIG.
The gas refrigerant at the state point A sucked into (1) is pressurized by the compressor (1) to be in the state of the high-temperature and high-pressure state point B. Then, it is condensed in the outdoor heat exchanger (4) and the pressurizing heat exchanger (5) to become a liquid refrigerant at state point C. The liquid refrigerant at state point C is the first
The pressure is reduced by the expansion valve (11) and becomes a low-temperature low-pressure two-phase refrigerant at the state point D. This refrigerant evaporates in the depressurizing heat exchanger (7) and becomes a two-phase refrigerant at the state point E where the degree of dryness is greater than the state point D. The refrigerant at the state point E evaporates in the main heat exchanger (3) to become a gas refrigerant at the state point A.

As described above, the primary refrigerant is a non-azeotropic refrigerant mixture, and in the two-phase state, as shown by the isotherms T1 and T2, the isotherm and the isobaric line intersect rather than become parallel. I have. That is, in the two-phase state, the temperature of the primary refrigerant increases when the enthalpy increases under a constant pressure condition. Therefore, the temperature at state point D is lower than the temperature at state point E. That is, the depressurizing heat exchanger (7) and the main heat exchanger
In (3), the refrigerant pressure is equal, but the temperature is different. That is, the temperature of the refrigerant in the pressure reducing heat exchanger (7) is lower than the temperature of the refrigerant in the main heat exchanger (3).

The above is the circulation operation of the refrigerant in the primary circuit (101).

Next, the circulation operation of the refrigerant in the secondary circuit (102) will be described.

In the secondary circuit (102), the secondary refrigerant is circulated by heat exchange with the primary refrigerant in the pressurizing heat exchanger (5) and the depressurizing heat exchanger (7). Driving force is generated. That is, the secondary-side evaporator (52) of the pressurizing heat exchanger (5)
Then, a high pressure is generated with the evaporation of the refrigerant, and a low pressure is generated with the condensation of the refrigerant in the secondary side condensation section (72) of the pressure reducing heat exchanger (7). Therefore, the internal pressure of the second main tank (22) and the sub tank (23) becomes high (pressurizing operation), and conversely,
The internal pressure of the first main tank (21) becomes low (pressure reduction operation).

As a result, as shown by the one-dot chain line arrow in FIG. 2, the liquid refrigerant pushed out from the second main tank (22) passes through the second four-way switching valve (25) and then flows into the main liquid pipe (25). After being reduced in pressure by the second expansion valves (14, 14,...), They flow into the indoor heat exchangers (8, 8,...). This refrigerant is an indoor heat exchanger
At (8,8, ...), it exchanges heat with the room air to evaporate and cool the room air. The refrigerant flowing out of the indoor heat exchanger (8,8, ...)
It flows through the main gas pipe (53) and flows into the secondary heat exchange section (32) of the main heat exchanger (3). Here, the secondary-side refrigerant exchanges heat with the primary-side refrigerant of the primary-side heat exchange section (31) and condenses. The condensed secondary refrigerant flows through the main liquid pipe (48), flows through the liquid pipe (46) via the second four-way switching valve (25), and is collected in the first main tank (21). .

On the other hand, the gas refrigerant in the first main tank (21) is condensed in the secondary side condensing section (72) of the pressure reducing heat exchanger (7),
A circulation operation for returning to the first main tank (21) is performed. That is,
The gas refrigerant in the first main tank (21) is sucked and passes through a gas recovery pipe (43a) to a secondary-side condensing section of the decompression heat exchanger (7).
(72). This refrigerant exchanges heat with the primary refrigerant in the primary evaporator (71) to condense. The condensed secondary refrigerant is collected in the first main tank (21) through the liquid pipe (47a).

The sub tank (23) is a heat exchanger for pressurization.
Since the pressure is equalized with that of the secondary evaporator (52) of (5), the liquid refrigerant in the sub-tank (23) is added through the liquid recovery pipe (42) as shown by the dashed line arrow in FIG. It is supplied to the secondary side evaporator (52) of the pressure heat exchanger (5). The supplied liquid refrigerant evaporates in the secondary evaporator (52) and contributes to pressurization of the second main tank (22). Thereafter, when most of the liquid refrigerant in the sub-tank (23) is supplied to the secondary-side evaporator (52), the sub-tank (23)
The pressurized solenoid valve (SV-P3) of the sub-tank (23) is opened while the pressurized solenoid valve (SV-P3) of the sub-tank (23) is opened. As a result, the pressure in the sub tank (23) becomes low, and a part of the refrigerant flowing through the liquid supply pipe (44) is recovered as shown by a two-dot chain line arrow in FIG.

After performing such an operation for a predetermined time, the solenoid valve of the secondary circuit (102) is switched. That is, the pressure reducing solenoid valve (SV-V1) of the first main tank (21), the second main tank
The pressurizing solenoid valve (SV-P2) of (22) and the pressure reducing solenoid valve (SV-V3) of the sub tank (23) are closed. Pressurizing solenoid valve (SV-P1) of the first main tank (21), pressure reducing solenoid valve of the second main tank (22)
(SV-V2) and the pressurized solenoid valve (SV-P3) of the sub tank (23) are opened.

Thus, the internal pressure of the second main tank (22) becomes low, and conversely, the internal pressure of the first main tank (21) and the sub tank (23) becomes high. Therefore, the liquid refrigerant extruded from the first main tank (21) circulates in the same manner as described above and is collected in the second main tank (22), and the liquid refrigerant in the sub tank (23) is circulated. Is a heat exchanger for pressurization
(5). Also in this case, when most of the liquid refrigerant in the sub tank (23) is supplied to the pressurizing heat exchanger (5), the pressurized solenoid valve (SV-P3) of the sub tank (23) is closed, and The pressure reducing solenoid valve (SV-V3) of the sub tank (23) is opened, and the refrigerant is recovered to the sub tank (23).

By repeating the switching operation of each solenoid valve as described above, the refrigerant circulates in the secondary circuit (102), and the room is cooled.

(Heating operation) Next, the heating operation will be described. In the heating operation, each four-way switching valve (2, 25) is set on the solid line side in the figure.

As shown in FIG. 4, in the primary circuit (101), the refrigerant discharged from the compressor (1) is branched after passing through the first four-way switching valve (2). One of the divided refrigerants is condensed in the main heat exchanger (3). The other divided refrigerant is condensed in the pressurizing heat exchanger (5). Refrigerants condensed in the main heat exchanger (3) and the pressurizing heat exchanger (5) merge, are decompressed by the first expansion valve (11), and then flow into the depressurizing heat exchanger (7). A part of the refrigerant evaporates in the pressure reducing heat exchanger (7). The refrigerant flowing out of the pressure-reducing heat exchanger (7) is further evaporated in the outdoor heat exchanger (4), and then the first four-way switching valve (2)
And is sucked into the compressor (1).

In the secondary circuit (102), the refrigerant extruded from one of the main tanks (21, 22) evaporates in the main heat exchanger (3), and then the main gas pipe (53) ),
Each indoor heat exchanger (8, 8, ...) exchanges heat with indoor air to condense. At this time, the room air is heated, and the room is heated. The refrigerant flowing out of the indoor heat exchangers (8, 8,...) Flows through the main liquid pipe (49) and is collected in the other main tanks (21, 22). The pressurizing operation of the pressurizing heat exchanger (5), the depressurizing operation of the depressurizing heat exchanger (7), and the operation of the sub-tank (23) are the same as those of the cooling operation described above, and therefore description thereof will be omitted.

-Effect of Air Conditioner (100)-As described above, according to the air conditioner (100), R407C is used as the primary refrigerant, and the primary refrigerant is subjected to the decompression heat during the cooling operation. The heat is passed while evaporating in the order of the exchanger (7) and the main heat exchanger (3). Therefore, the refrigerant temperature of the primary evaporator (71) of the decompression heat exchanger (7) depends on the main heat exchanger.
The temperature is lower than the refrigerant temperature of the primary heat exchange section (31) in (3). As a result, the secondary condenser (7
The temperature of the secondary refrigerant in (2) becomes lower than the temperature of the secondary refrigerant in the secondary heat exchange section (32) of the main heat exchanger (3). Therefore,
Since the secondary-side condenser (72) can be maintained at a lower pressure than the secondary-side heat exchange part (32), the circulation operation of the secondary-side refrigerant can be performed well.

Since the refrigerant pressure in the primary evaporator (71) of the pressure reducing heat exchanger (7) is equal to the refrigerant pressure in the primary heat exchanger (31) of the main heat exchanger (3), The refrigerant sucked into the compressor (1) never becomes lower in pressure than the refrigerant pressure at the outlet of the main heat exchanger (3). Therefore, an increase in the load on the compressor (1) due to the provision of the depressurizing heat exchanger (7) can be avoided, and C
OP can be prevented from lowering.

-Other Embodiments- In the above embodiment, the heat transfer device according to the present invention is applied to a so-called heat pump type air conditioner. However, the application target of the heat transfer device according to the present invention is not limited to the air conditioner (100), and is applied to, for example, an air conditioner (200) as a so-called cooling only machine as described below. You can also.

As shown in FIG. 5, the present air conditioner (200)
, The primary circuit (101) includes a compressor (1), an outdoor heat exchanger (4), a heat exchanger for pressurization (5), a first expansion valve (11), and a heat exchanger for decompression. (7) and the main heat exchanger (3) are sequentially connected to form a closed circuit.

On the other hand, in the secondary circuit (102), the secondary circuit (102) of the air conditioner (100)
The four-way switching valve (25) is removed, and the liquid supply pipe (44) is directly connected to the main pipe (49), and the main liquid pipe (48) is directly connected to the liquid pipe (46).

The circulation operation of the refrigerant is performed by the above air conditioner (10).
This is the same as in the cooling operation of 0). Therefore, the primary circuit (10
In 1), the primary-side refrigerant flows while evaporating in the order of the pressure-reducing heat exchanger (7) to the main heat exchanger (3).

As a result, the same effect as that of the air conditioner (100) can be obtained.

-Modifications- The primary-side refrigerant is not limited to R407C, but may be any other refrigerant as long as its temperature rises according to heat absorption.

Further, the primary circuit (101) may be constituted by a heat medium circuit in which a heat medium such as water or brine circulates, instead of the refrigerant circuit. In this case, the high temperature side circuit in which the high temperature heat medium circulates and the low temperature side circuit in which the low temperature heat medium circulates,
The secondary circuit (101) is constructed, and the high-temperature circuit is connected to the pressurizing heat exchanger (5). In the low-temperature side circuit, the depressurizing heat exchanger (7) and the main heat exchanger (so that the low-temperature heat medium flows from the depressurizing heat exchanger (7) to the main heat exchanger (3) in this order. 3)
Are connected in series. Also in this case, since the temperature of the heat medium such as water or brine rises in accordance with heat absorption, the same effect as that of the air conditioner (100) can be obtained.

[0072]

As described above, according to the first aspect of the present invention, the heat medium in the primary circuit flows from the pressure reducing heat exchanger to the main heat exchanger while increasing the temperature. Therefore, while the pressures of the heat medium in the pressure-reduction heat exchanger and the main heat exchanger are equal, the heat medium in the pressure-reduction heat exchanger is lower in temperature than the heat medium in the main heat exchanger. As a result, the pressure of the secondary refrigerant in the pressure reducing heat exchanger becomes lower than the pressure of the secondary refrigerant in the main heat exchanger. Therefore, the load on the heat medium transporting means of the primary circuit is reduced, so that the COP can be prevented from lowering and the secondary refrigerant can be circulated satisfactorily.

According to the second aspect of the present invention, an air conditioner or the like as a so-called cooling only machine can be obtained with a specific configuration.

According to the third aspect of the present invention, it is possible to obtain a so-called heat pump type air conditioner capable of reversible operation with a specific configuration.

According to the invention described in claim 4 or 5,
With a specific configuration, it is possible to obtain a refrigerant having a characteristic that the temperature rises according to heat absorption.

[Brief description of the drawings]

FIG. 1 is a refrigerant circuit diagram of an air conditioner.

FIG. 2 is a refrigerant circuit diagram illustrating a refrigerant circulation operation during a cooling operation.

FIG. 3 is a Mollier chart during a cooling operation.

FIG. 4 is a refrigerant circuit diagram illustrating a refrigerant circulation operation during a heating operation.

FIG. 5 is a refrigerant circuit diagram of the air conditioner.

FIG. 6 is a refrigerant circuit diagram of a conventional air conditioner.

[Explanation of symbols]

 (1) Compressor (2) Fourth-way switching valve (3) Main heat exchanger (4) Outdoor heat exchanger (5) Heat exchanger for pressurization (7) Heat exchanger for decompression (8) Indoor heat exchange (11) First expansion valve (21) First main tank (22) Second main tank (23) Sub tank

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tadashi Iao, 1304 Kanaokacho, Sakai-shi, Osaka Daikin Industries Inside Kanaoka Plant of Sakai Seisakusho Co., Ltd. (72) Inventor Satoru Okura 1304, Kanaokacho, Sakai-shi, Osaka Daikin Industries Stock Sakai Factory Kanaoka Factory

Claims (5)

[Claims] A primary circuit (10) through which a primary heat medium circulates.
1) and a secondary circuit (102) through which a secondary refrigerant circulates. In the primary circuit (101), a heat medium transporting means (1), a heat source side heat exchanger (4) A decompression heat exchanger (7) for removing heat from the secondary refrigerant and generating a low pressure in the secondary circuit (102);
Main heat exchanger for exchanging heat between primary side heat medium and secondary side refrigerant
(3), while the secondary circuit (102) is connected between the main heat exchanger (3) and the indoor heat exchanger (8, 8,. 49) and the use side circuit in which the refrigerant circulates through the main gas pipe (53) to carry
(102a) and tank (21,2) connected to main liquid piping (48,49)
2) The tanks (21, 22) are pressurized to increase the use side circuit (102a).
Pressurizing means (5) for extruding the refrigerant into the tank, and the tank
The decompression heat exchanger (7) for recovering the refrigerant from the use side circuit (102a) is connected to the (21, 22), and the driving force generation for generating the driving force of the refrigerant circulation of the use side circuit (102a) is performed. A heat transfer device having a circuit (102b), wherein the primary-side heat medium is a heat medium having a characteristic that a temperature rises according to heat absorption, and the primary-side heat medium is depressurized during a cooling operation. Heat exchanger
In the primary side circuit (101), the depressurizing heat exchanger (7) and the main heat exchanger (3) are connected so that heat flows from (7) to the main heat exchanger (3) while absorbing heat. Are connected in series. 2. The heat transfer device according to claim 1, wherein the primary heat medium undergoes a phase change in the primary circuit (101).
The heating medium conveying means is constituted by a compressor (1), while the pressurizing means is a pressurizing heat exchanger (5) for heating the secondary refrigerant with the primary refrigerant. The primary circuit (101) is configured so that the primary circuit (101) discharges from the compressor (1).
The secondary refrigerant is heat source side heat exchanger (4) and pressurized heat exchanger
It is condensed in (5), decompressed in the decompression mechanism (11), and circulates while evaporating in order from the decompression heat exchanger (7) to the main heat exchanger (3).
A heat transfer device comprising a closed circuit configured to perform circulation returning to the compressor (1). 3. The heat transfer device according to claim 1, wherein the primary heat medium undergoes a phase change in the primary circuit (101).
The heating medium conveying means is constituted by a compressor (1), while the pressurizing means is a pressurizing heat exchanger (5) for heating the secondary refrigerant with the primary refrigerant. The primary circuit (101) includes a four-way switching valve (2) connected to the discharge pipe and the suction pipe of the compressor (1), and switches the four-way switching valve (2). During the cooling operation, the primary refrigerant discharged from the compressor (1) passes through the four-way switching valve (2) and then passes through the heat source side heat exchanger.
(4) and condensed in the pressurizing heat exchanger (5), decompressed by the decompressing mechanism (11), and circulated while evaporating from the depressurizing heat exchanger (7) to the main heat exchanger (3). While circulating through the four-way switching valve (2) and returning to the compressor (1), during the heating operation, the primary refrigerant discharged from the compressor (1) flows through the four-way switching valve ( 2) After passing through the main heat exchanger
(3) and condensed in the pressurizing heat exchanger (5), decompressed by the depressurizing mechanism (11), and evaporated in the depressurizing heat exchanger (7) and the heat source side heat exchanger (4), A heat transfer device for circulating through the four-way switching valve (2) and returning to the compressor (1). 4. The heat transfer device according to claim 2, wherein the primary-side refrigerant is a non-azeotropic mixed refrigerant. 5. The heat transfer device according to claim 4, wherein the primary refrigerant is R407C.