JP2002257375A - Heat pump and dehumidifying-air conditioning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat pump with a high coefficient of performance(COP) and a dehumidifying-air conditioning device with a high dehumidifying capacity per energy consumption. SOLUTION: This device is provided with a booster 4 raising the pressure of refrigerant, a condenser 5 condensing the refrigerant, an evaporator 1 evaporating the refrigerant to cool down treated air to a dew-point temperature or below, branch refrigerant paths 42 to 44 branching into a plurality of lines between the condenser 5 and the evaporator 1, the first heat exchange part 21 evaporating the refrigerant at the intermediate pressure between the condensing pressure of the condenser 5 and the evaporating pressure of the evaporator 1 to cool down the treated air, the second heat exchange part 22 condensing the refrigerant at the intermediate pressure between the condensing pressure of the condenser 5 and the evaporating pressure of the evaporator 1 to heat the treated air, and treated-air paths connecting the first heat exchange part 21, the evaporator 1 and the second heat exchange part 22 in this order.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat pump and a dehumidifying air conditioner, and more particularly to a heat pump having a high operating coefficient (COP) and a dehumidifying air conditioner having such a heat pump and having a high dehumidifying capacity per energy consumption. .

[0002]

2. Description of the Related Art FIG. 10 shows a configuration of a conventional air conditioning system. As shown in FIG. 10, a conventional dehumidifying air conditioner includes a compressor 201 for compressing a refrigerant, a condenser 202 for condensing the refrigerant compressed by the compressor 201 with outside air OA, and an expansion valve 203 for condensing the refrigerant. And an evaporator 204 for evaporating the refrigerant and evaporating the refrigerant to cool the processing air from the air-conditioned space 100 to a temperature equal to or lower than the dew point.
And a reheater 205 that reheats the refrigerant downstream of the condenser 202 with the refrigerant upstream of the expansion valve 203. These compressors 2
01, the condenser 202, the reheater 205, the expansion valve 203, and the evaporator 204 constitute a heat pump HP that pumps heat from processing air flowing through the evaporator 204 to outside air OA flowing through the condenser 202.

FIG. 11 shows a conventional dehumidifying air conditioner.
It is a Mollier diagram of the heat pump HP when HFC134a is used as a refrigerant. In FIG. 11, the point a indicates the state of the refrigerant evaporated by the evaporator 204, and the refrigerant at this time is in a saturated gas state. The refrigerant pressure is 0.34
MPa, temperature 5 ° C, enthalpy 400.9 kJ / k
g. Point b indicates a state in which gas is sucked and compressed by the compressor 201, that is, a state at the discharge port of the compressor 201,
At this time, the refrigerant is in a superheated gas state.

The refrigerant gas in the state at the point b is supplied to the condenser 20
2 to reach the state shown by point c. At this time, the refrigerant is in a saturated gas state, and its pressure is 0.94 M
Pa, temperature is 38 ° C. The refrigerant is further cooled and condensed under this pressure to reach the state indicated by point d. At this time, the refrigerant is in a saturated liquid state, and its pressure and temperature are the same as the pressure and temperature at point c. The enthalpy at this time is 250.5 kJ / kg.

[0005] This refrigerant liquid is decompressed by the expansion valve 203,
The pressure is reduced to 0.34 MPa, which is the saturation pressure at a temperature of 5 ° C., to reach the state shown by point e. The refrigerant in the state of the point e reaches the evaporator 204 as a mixture of the refrigerant liquid and the gas at 5 ° C., in which the heat is removed from the processing air in the evaporator 204 and evaporated to become a saturated gas in the state indicated by the point a. . This saturated gas is sucked into the compressor 201 again, and the above-described cycle is repeated.

FIG. 12 is a psychrometric chart showing an air conditioning cycle in a conventional dehumidifying air conditioner. In FIG. 12, reference numerals K, L, and M correspond to the path states denoted by the respective reference numerals in FIG. As shown in FIG. 12, in the conventional dehumidifying air-conditioning apparatus, the air (state K) from the air-conditioned space 100 is cooled to the dew point temperature or lower by the evaporator 204, and the dry bulb temperature decreases and the absolute humidity decreases. State L is reached. This state L is on the saturation line in the psychrometric chart. The air in the state L is reheated by the reheater 205,
With the absolute humidity kept constant, the dry bulb temperature rises to reach state M,
The air is supplied to the air-conditioned space 100. In this state M, both the absolute humidity and the dry bulb temperature are lower than the state K.

[0007]

However, in the above-described conventional dehumidifying air conditioner, since the amount of cooling to the dew point is large, about half of the refrigerating effect in the evaporator of the heat pump is consumed to take the sensible heat load. , The dehumidifying capacity per power consumption (dehumidifying performance) was low. When a single-stage compressor is used as the heat pump compressor,
It becomes a compression refrigeration cycle of stage compression, and the operating coefficient (CO
P) was low, and the power consumption per dehumidification amount was large.

SUMMARY OF THE INVENTION The present invention has been made in view of such problems of the prior art, and has as its object to provide a heat pump having a high operating coefficient (COP) and a dehumidifying air conditioner having a high dehumidifying capacity per energy consumption. And

[0009]

In order to solve the problems in the prior art, one aspect of the present invention is to provide a booster for increasing the pressure of a refrigerant and to heat the high heat source fluid by condensing the refrigerant. A condenser, an evaporator that evaporates the refrigerant and cools the low heat source fluid, a branch refrigerant path that branches into a plurality of rows between the condenser and the evaporator, and the condenser and the evaporator. A first heat exchange means provided between and in the branch refrigerant path, evaporating a refrigerant at an intermediate pressure between the condensation pressure of the condenser and the evaporation pressure of the evaporator to cool the processing air; Between the condenser and the evaporator, in the branch refrigerant path, and condensing the refrigerant at a pressure intermediate between the condensation pressure of the condenser and the evaporation pressure of the evaporator to form the processing air. Heat exchange means for heating the first heat exchange means, and the first heat exchange means A heat pump, characterized in that a process air path for connecting the evaporator and the second heat exchange means in this order.

Another aspect of the present invention is a pressure booster for pressurizing a refrigerant, a condenser for condensing the refrigerant to heat a high heat source fluid, and evaporating the refrigerant to reduce the processing air to a dew point temperature or lower. An evaporator that cools down, a branch refrigerant path that branches into a plurality of rows between the condenser and the evaporator, and is provided in the branch refrigerant path between the condenser and the evaporator, First heat exchange means for evaporating a refrigerant at a pressure intermediate between the condensation pressure of the condenser and the evaporation pressure of the evaporator to cool the processing air, and between the condenser and the evaporator. A second heat exchange means provided in the branch refrigerant path to condense refrigerant at a pressure intermediate between the condensation pressure of the condenser and the evaporation pressure of the evaporator to heat the processing air; and The first heat exchange means, the evaporator, and the second heat exchange means A dehumidifying air-conditioning apparatus characterized by comprising a process air path for connecting in turn.

[0011] With this configuration, the low heat source fluid can be pre-cooled in the first heat exchange means before cooling in the evaporator,
Using the heat of pre-cooling, after cooling in the evaporator, the low heat source fluid is heated in the second heat exchange means, and the processing air is set to a low heat source, and the processing air is cooled to the dew point or lower by the evaporator. By doing so, it is possible to provide a dehumidifying air-conditioning apparatus that consumes less energy per dehumidifying amount.

Further, by providing the branch refrigerant path, the operating temperature of the refrigerant can be changed stepwise, so that the heat exchange efficiency can be increased. here,
The heat exchange efficiency φ is obtained by calculating the heat exchanger inlet temperature of the fluid on the high temperature side as T
When P1, the outlet temperature is T, the heat exchanger inlet temperature of the low-temperature fluid is TC1, and the outlet temperature is TC2, if attention is paid to cooling of the high-temperature fluid, that is, if the purpose of heat exchange is cooling, , Φ = (TP1-TP2) / (TP1-TC1),
When attention is paid to heating of a low-temperature fluid, that is, when the purpose of heat exchange is heating, φ = (TC2−TC1) / (TP1−
TC1).

In a preferred aspect of the present invention, the branch refrigerant paths extend in parallel inside the evaporator and join at a downstream side of the evaporator. In this case,
An ejector that pressurizes the refrigerant that exchanges heat with the low-temperature processing air by the refrigerant that has passed through the refrigerant path is installed in the refrigerant path through which the refrigerant that exchanges heat with the high-temperature processing air passes. May be.

With such a configuration, the operating temperature of the evaporator increases, so that the theoretical refrigeration effect increases, the theoretical compression work decreases, and the efficiency can be increased. Also, since the specific volume of the refrigerant decreases, the flow rate of the refrigerant sucked by the booster increases. Therefore, the amount of dehumidification increases with an increase in the freezing effect, and the efficiency can be improved.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a dehumidifying air conditioner according to the present invention will be described below with reference to FIGS. FIG. 1 is a diagram showing an entire configuration of an air conditioning system according to the present embodiment, and FIG. 2 is a diagram schematically showing a flow in a dehumidifying air conditioner according to the first embodiment. The dehumidifying air-conditioning apparatus according to the present embodiment cools air (process air) in the air-conditioned space 100 to a temperature lower than its dew point and dehumidifies the air, and includes a heat pump HP1 therein. The processing air whose humidity has been reduced by the dehumidifying air-conditioning device
By returning to 0, the air-conditioned space 100 is maintained in a comfortable environment.

As shown in FIG. 1, the dehumidifying air conditioner includes an indoor unit 10 installed in an air-conditioned space 100 and an air-conditioned space 10.
And the outdoor unit 20 installed outside (outdoor). The indoor unit 10 of the dehumidifying air conditioner includes a refrigerant evaporator 1 for evaporating the refrigerant, a heat exchanger 2 for exchanging heat between the refrigerant and the processing air, and a blower 3 for circulating the processing air. I have. The heat exchanger 2 indirectly exchanges heat between processing air before and after flowing into the evaporator 1 via a refrigerant, and a first heat for evaporating the refrigerant and cooling the processing air. An exchange unit 21 and a second heat exchange unit 22 for condensing the refrigerant and heating the processing air are provided.
The outdoor unit 20 of the dehumidifying air conditioner includes a booster 4 that compresses the refrigerant, a refrigerant condenser 5 that cools and condenses the refrigerant,
A blower 6 for blowing cooling air.

A path through which the processing air flows (a processing air path)
As shown in FIG. 2, a path 30 connecting the air-conditioned space 100 and the first heat exchange unit 21 of the heat exchanger 2 and a path 31 connecting the first heat exchange unit 21 and the evaporator 1 A path 32 connecting the evaporator 1 and the second heat exchange section 22 of the heat exchanger 2; a path 33 connecting the second heat exchange section 22 and the blower 3; And a path 34 connecting the two. The first heat exchange part 21 of the heat exchanger 2, the evaporator 1, and the second heat exchange part 22 of the heat exchanger 2 are sequentially connected by such a processing air path.

On the other hand, the refrigerant path includes a path 40 connecting the evaporator 1 and the booster 4, a path 41 connecting the booster 4 and the condenser 5, and connecting the condenser 5 and the evaporator 1. And a route. Here, a path connecting the condenser 5 and the evaporator 1 is branched into a plurality of rows (three rows in FIG. 2) on the downstream side of the condenser 5, and the branched refrigerant paths 42 to 4 are provided.
4 are formed. The branch refrigerant paths 42 to 44 are
At the upstream side of the evaporator 1, it joins one path 45.

Outside air OA as cooling air is introduced into the condenser 5 through a passage 46. The outside air OA removes heat from the condensing refrigerant, and the heated outside air is sucked into the blower 6 via the path 47 and discharged outside via the path 48 (EX).

The branch refrigerant passages 42 to 44 pass through the first heat exchange part 21 and the second heat exchange part 22 of the heat exchanger 2, respectively. An evaporating section 51 is formed to cool the processing air flowing through the first heat exchange section 21 by evaporating the refrigerant, and the second section is formed in the second heat exchange section 22 by condensing the refrigerant.
A condensing section 52 for heating (reheating) the processing air flowing through the heat exchange section 22 is formed. In each of the branch refrigerant paths 42 to 44, throttles 11 to 13 are arranged on the upstream side of the first heat exchange section 21, respectively.
The throttles 14 to 16 are respectively arranged on the downstream side of.
As these apertures 11 to 16, for example, orifices,
A capillary tube, an expansion valve, or the like can be used.

FIG. 3 shows the heat exchanger 2 of the dehumidifying air conditioner of FIG.
It is an enlarged view which shows the branch refrigerant paths 42-44 in.
The refrigerant path including the evaporating section 51 and the condensing section 52 passes through the first heat exchange section 21 and the second heat exchange section 22 alternately and repeatedly. That is, as shown in FIG. 3, the branch refrigerant path 42 includes, in order from the condenser 5 side, an evaporation section 61a, a condensation section 62a, a condensation section 62b, an evaporation section 61b, an evaporation section 61c, and a condensation section 62c. I have. Similarly, the branch refrigerant path 43 is connected to the evaporating section 63.
a, a condensing section 64a, a condensing section 64b, an evaporating section 63b, an evaporating section 63c, and a condensing section 64c. The branch refrigerant path 44 includes an evaporating section 65a, a condensing section 66a, and a condensing section 6.
6b, evaporating section 65b, evaporating section 65c,
It has a condensation section 66c.

Here, the first heat exchange section 21 for flowing the processing air before passing through the evaporator 1 and the second heat exchange section 22 for flowing the processing air after passing through the evaporator 1 are separately provided. The evaporator 1 described above is disposed between the first heat exchange unit 21 and the second heat exchange unit 22. For reference, the arrangement of the heat exchanger and the evaporator when the refrigerant path is not branched is shown in FIGS.
(B). FIG. 4A is a perspective view seen from the front side, and FIG. 4B is a perspective view seen from the back side.

First heat exchange section 21 and second heat exchange section 2
In 2, a plurality of heat exchange tubes are arranged in parallel as a refrigerant path on a surface orthogonal to the flow of the processing air. Evaporation section 61a and condensing section 62a, evaporating section 61b and condensing section 62b, evaporating section 6
Between corresponding sections such as 1c and the condensing section 62c, a tube is provided that straddles the evaporator 1 (FIG. 4).
(See (b)), the corresponding evaporating section and condensing section are connected to each other. Also, the evaporating section 61b
And the end of the evaporation section 61c, the evaporation section 63b
And the end of the evaporating section 63c, the evaporating section 65b
The ends of the evaporating section 65c are connected by U-tubes (YouTubes) 68, respectively. Similarly, the ends of the condensing sections 62a and 62b, the ends of the condensing sections 64a and 64b, and the ends of the condensing sections 66a and 66b are connected by the U-tube 69, respectively (FIG. 4 (a)). )reference).

With such a configuration, for example, the refrigerant flowing from the evaporating section 61a to the condensing section 62a in the refrigerant path 42 is guided to the condensing section 62b by the U-tube 69. The refrigerant guided to the condensing section 62b further flows into the evaporating section 61b, is introduced into the evaporating section 61c by the U-tube 68, and further flows into the condensing section 62c. As described above, the refrigerant path is formed by the meandering small tube group, and the small tube group passes through the insides of the first heat exchange unit 21 and the second heat exchange unit 22 while meandering. It comes into contact with the processing air alternately.

As shown in FIGS. 1 and 2, a drain pan 7 is provided inside the indoor unit 10 of the dehumidifying air conditioner. This drain pan 7 is not only the evaporator 1 but also the heat exchanger 2. Is preferably provided so as to cover also the lower part of the upper part. In the first heat exchange section 21 of the heat exchanger 2, the processing air is mainly precooled. However, since a part of water may condense here, it is particularly preferable to provide the water below the first heat exchange section 21. preferable.

Next, the flow of the refrigerant between the devices is shown in FIG.
This will be described with reference to FIG. The refrigerant gas compressed by the booster 4 is guided to the condenser 5 via the refrigerant gas pipe 41 connected to the discharge port of the booster 4, and is cooled and condensed by outside air OA as cooling air. The liquid refrigerant that has exited from the condenser 5 is branched into branch refrigerant paths 42 to 44. Hereinafter, the refrigerant flowing through the refrigerant path 42 will be mainly described, and the description of the refrigerant flowing through the other refrigerant paths 43 and 44 will be omitted because it is the same as this.

The refrigerant flowing through the branch refrigerant path 42 is
At 1, the pressure is reduced and expanded, and a part of the liquid refrigerant evaporates (flashes). The refrigerant in which the liquid and the gas are mixed reaches the evaporating section 61a, where the liquid refrigerant is supplied to the evaporating section 61a.
Flow so as to wet the inner wall of the tube. The liquid-phase refrigerant flows into the evaporating section 61a, but the refrigerant flowing into the evaporating section 61a may be a liquid refrigerant that is partially vaporized and contains a small amount of a gas phase. While flowing through the evaporating section 61a, the liquid refrigerant evaporates, and the processing air before flowing into the evaporator 1 is cooled (precooled), and the refrigerant itself is heated to increase the gas phase.

As described above, since the evaporating section 61a and the condensing section 62a are constituted by a series of tubes, the refrigerant gas evaporated in the evaporating section 61a (and the non-evaporated liquid refrigerant) flows into the condensing section 62a. I do. In the condensing section 62a, the processing air that has been cooled and dehumidified in the evaporator 1 and has a lower temperature than the processing air in the evaporating section 61a is heated (reheated), and the refrigerant itself loses heat and condenses the gas-phase refrigerant. ,
It flows into the next condensation section 62b. While flowing through the condensing section 62b, the refrigerant is further deprived of heat by the low-temperature process air, thereby further condensing the gas-phase refrigerant.

The condensed liquid refrigerant flows into the next evaporating section 61b and the following evaporating section 61c,
The processing air before flowing into the evaporator 1 is cooled (precooled) in the same manner as described above. Further, the refrigerant gas flows into the condensation section 62c, and the processing air is heated (reheated). As described above, the refrigerant flows through the branch refrigerant path while changing the phase between the gas phase and the liquid phase, and the processing air before being cooled by the evaporator 1 and the processing air cooled by the evaporator 1 to reduce the absolute humidity. Heat exchange takes place indirectly with the air.

The liquid refrigerant condensed in the condensing section 62c is decompressed and expanded by the throttle 14 arranged on the downstream side of the second heat exchange section 22, and its temperature is lowered. Then, the refrigerant merges with the refrigerant flowing through the other branch refrigerant paths 43 and 44, and the merged refrigerant reaches the evaporator 1 through the path 45. Evaporator 1
Then, the refrigerant evaporates, and the processing air is cooled by the heat of evaporation. The refrigerant evaporated and gasified by the evaporator 1 is guided to the suction side of the booster 4 through the path 40. Then, the above-described cycle is repeated.

Next, the operation of the heat pump HP1 included in the dehumidifying air conditioner of this embodiment will be described.
FIG. 5 shows a heat pump HP included in the dehumidifying air conditioner of FIG.
1 is a refrigerant Mollier diagram of FIG. In the diagram shown in FIG. 5, HFC134a is used as a refrigerant, and the enthalpy is plotted on the horizontal axis and the pressure is plotted on the vertical axis. HFC13
In addition to HFC134a, HFC407C and HFC410A can also be used as refrigerants. When these refrigerants are used, the operating pressure range shifts to a higher pressure side than in the case of HFC134a.

In FIG. 5, point a indicates the state of the refrigerant evaporated by the evaporator 1 in FIG. 2, and the refrigerant at this time is in a saturated gas state. The pressure of the refrigerant is 0.234 MPa, the temperature is 5 ° C., and the enthalpy is 395.1 kJ / kg.
Point b indicates a state where this gas is sucked and compressed by the booster 4, that is, a state at the discharge port of the booster 4, and the refrigerant at this time has a pressure of 0.706 MPa and is in a superheated gas state. .

The refrigerant gas in the state at the point b is cooled in the condenser 2 to reach the state shown at the point c. At this time, the refrigerant is in a saturated gas state, and its pressure is 0.706MP.
a, The temperature is 38 ° C. The refrigerant is further cooled and condensed under this pressure to reach the state indicated by point d. At this time, the refrigerant is in a saturated liquid state, and its pressure and temperature are the same as the pressure and temperature at point c. The enthalpy at this time is 237.4 kJ / kg.

This refrigerant liquid flows into the heat exchanger 2 after being divided into the branch refrigerant paths 42 to 44. First, the refrigerant passing through the refrigerant path 43 will be described. The refrigerant liquid flowing into the refrigerant passage 43 is decompressed by the throttle 12 and flows into the evaporating section 63a of the first heat exchange unit 21. The state at this time is point e
The liquid is partially evaporated and the liquid and the gas are mixed. The pressure at this time is an intermediate pressure between the condensing pressure of the condenser 5 and the evaporating pressure of the evaporator 1, and is a value between 0.234 MPa and 0.706 MPa in the present embodiment.

In the evaporating section 63a, the refrigerant liquid evaporates under the above-mentioned intermediate pressure, and the state becomes a point f1 located between the saturated liquid line and the saturated gas line at the same pressure. In this state, a part of the liquid has evaporated, but a considerable amount of the refrigerant liquid remains.
Then, the refrigerant in the state indicated by the point f1 flows into the condensation sections 64a and 64b. Condensing section 64a
And 64b, the refrigerant is deprived of heat by the low-temperature processing air flowing through the second heat exchange section 22, and reaches the state of the point g1.

The refrigerant in the state at the point g1 is supplied to the evaporating section 6
3b and 63c, where heat is deprived and the liquid phase is increased to reach the state at point f2.
Flows into. In the condensing section 64c, the refrigerant increases its liquid phase and reaches the state at the point g2. The point g2 is located on the saturated liquid line in the Mollier diagram. At this time, the temperature of the refrigerant is 18 ° C., and the enthalpy is 209.5 kJ / kg.

The refrigerant liquid in the state at the point g2 is reduced in pressure by the throttle 15 to a saturation pressure of 0.234 MPa at a temperature of 5 ° C., and reaches a state indicated by a point h. The refrigerant in the state at the point h reaches the evaporator 1 as a mixture of the refrigerant liquid and the gas at 5 ° C., where it takes heat from the processing air and evaporates to a saturated gas in the state indicated by the point a. This saturated gas is sucked into the booster 4 again, and the above-described cycle is repeated.

Similarly, the refrigerant passing through the refrigerant path 42 passes through the restrictor 11, the evaporating section, the condensing section, and the restrictor 14, and passes through the states indicated by points j, i1, k1, i2, and k2 to point l. It reaches the state shown by. The refrigerant passing through the refrigerant path 44 passes through the throttle 13, the evaporating section, the condensing section, and the throttle 16, and passes through points m, n1, o1, n2,
The state shown by the point p is reached through the state shown by the point o2.

As described above, in the heat exchanger 2, the refrigerant changes its evaporation state in the evaporating section 51 from point e to point f1 or from point g1 to point f2.
In the condensing section 52, the state of condensation changes from point f1 to point g1 or from point f2 to point g2, and the heat transfer coefficient is very high because the evaporation heat transfer and the condensation heat transfer are performed. High heat exchange efficiency.

Here, the booster 4, the condenser 5, the throttles 11 to 11
Considering the compression heat pump HP1 including the evaporator 16 and the evaporator 1, when the heat exchanger 2 according to the present invention is not provided, the refrigerant in the state of the point d in the condenser 5 is returned to the evaporator 1 via the throttle. Therefore, the enthalpy difference usable in the evaporator 1 is 395.1-237.4 = 157.7 kJ / kg.
There is only. However, when the heat exchanger 2 according to the present invention is provided, 395.1-209.5 = 185.6 kJ / k.
g, and the amount of gas circulating through the compressor for the same cooling load, and hence the required power, is 15% (= 1-157.7 /
185.6) can also be reduced. That is, the same operation as in the subcool cycle can be provided.

FIG. 6 is a psychrometric chart showing an air conditioning cycle in the dehumidifying air conditioner of FIG. In FIG. 6, reference signs K, L, M, and X correspond to the path states denoted by the respective reference signs in FIG. The processing air (state K) from the air-conditioned space 100 is sent to the first heat exchange section 21 of the heat exchanger 2 through the processing air path 30 and is cooled to a certain extent by the refrigerant evaporated in the evaporation section 51. You. Since this is preliminary cooling before the evaporator 1 is cooled to a temperature equal to or lower than the dew point, it can be called precooling. While being precooled in the evaporating section 51, the processing air reaches a point X on the saturation line while removing a certain amount of water and slightly reducing the absolute humidity. Alternatively, in the pre-cooling stage, the point K
It may be cooled to an intermediate point between the point X and the point X. Alternatively, the cooling may be performed to a point beyond the point X to a point slightly shifted to the low humidity side on the saturation line.

The processing air precooled in the first heat exchange section 21 is introduced into the evaporator 1 through the path 31. In the evaporator 1, the processing air is cooled to a temperature lower than its dew point temperature by the refrigerant that evaporates at a low temperature, which is depressurized by the throttles 14 to 16. , To the point L. In FIG. 6, the bold line indicating the change from the point X to the point L is drawn out of the saturation line for convenience, but actually overlaps the saturation line.

The processing air in the state at the point L flows into the second heat exchange section 22 of the heat exchanger 2 through the path 32, and is heated by the refrigerant condensing in the condensing section 52 while keeping the absolute humidity constant. It reaches point M. Point M is air of moderate relative humidity, where the absolute humidity is much lower than point K and the dry bulb temperature is not too low. The air in the state of the point M is sucked by the blower 3 and returned to the air-conditioned space 100 through the path 34.

Here, in the cycle on the processing air side shown in the psychrometric chart of FIG. 6, the amount of heat obtained by pre-cooling the processing air in the first heat exchange section 21, that is, the processing air in the second heat exchange section 22 is supplied. The reheated heat amount ΔH is the heat recovery amount, and the heat amount obtained by cooling the processing air in the evaporator 1 is ΔQ. Air-conditioned space 100
Is cooled, and the cooling effect is Δi.

As described above, in the heat exchanger 2, the processing air is precooled by the evaporation of the refrigerant in the evaporation section 51,
The condensing of the refrigerant in the condensing section 52 reheats the process air. And the refrigerant evaporated in the evaporating section 51 is
It condenses in the condensing section 52. As described above, heat exchange between the processing air before and after being cooled by the evaporator 1 is indirectly performed by the same evaporation and condensation of the refrigerant.

As described above, in the present embodiment, the heat transfer medium of the evaporator for cooling the processing air to the dew point or lower, the pre-cooler for pre-cooling the processing air, and the re-heater for re-heating are the same refrigerant. As a result, the refrigerant system is simplified to a single unit, the pressure difference between the evaporator and the condenser can be used, the circulation becomes active, and a phase change occurs in heat exchange between pre-cooling and reheating. Since the accompanying boiling phenomenon can be applied, the efficiency can be increased.

In the above-described embodiment, an example in which the refrigerant path is branched into three rows has been described. However, the present invention is not limited to this, and the refrigerant path may be branched into any number of rows. FIG. 7 is a graph showing the relationship between the number of rows of branch refrigerant paths and the temperature efficiency in the dehumidifying air conditioner according to the present invention. From FIG. 7, it can be inferred that the temperature efficiency is improved by increasing the number of rows of the branch refrigerant paths. As described above, by providing the refrigerant paths branched in a plurality of rows, the working temperature of the refrigerant can be changed stepwise, so that the heat exchange efficiency can be increased.

Next, a second embodiment of the dehumidifying air conditioner according to the present invention will be described with reference to FIGS. FIG. 8 is a diagram schematically showing a flow in the dehumidifying air conditioner in the second embodiment, and FIG. 9 is a refrigerant Mollier diagram of the heat pump HP2 included in the dehumidifying air conditioner of FIG. Note that the same reference numerals are given to members or elements having the same operation or function as the members or elements in the above-described first embodiment,
Parts that are not particularly described are the same as in the first embodiment.

Also in the present embodiment, the refrigerant paths are branched into a plurality of rows on the downstream side of the condenser 5, and the branched refrigerant paths 142 to 144 are formed. The third embodiment differs from the first embodiment in that the first embodiment extends to the inside of the vessel 101 and joins downstream of the evaporator 101. These branch refrigerant paths 142
To 144, the refrigerant path through which the refrigerant that exchanges heat with the processing air having a high temperature passes, that is, the branch refrigerant path 142 includes:
An ejector 8 is provided for increasing the pressure of the refrigerant that exchanges heat with the processing air having a low temperature, that is, the refrigerant that has passed through the refrigerant passage 144.

In FIG. 9, point a is the evaporator 101 in FIG.
Shows the state of the refrigerant evaporated, and the refrigerant at this time is in a saturated gas state. The pressure is 0.262 MPa, the temperature is 8 ° C., and the enthalpy is 396.8 kJ / kg. Point b indicates a state where this gas is sucked and compressed by the booster 4, that is, a state at the discharge port of the booster 4, and the refrigerant at this time has a pressure of 0.706 MPa and is in a superheated gas state. .

The refrigerant gas in the state at the point b is cooled in the condenser 5 to reach the state shown at the point c. At this time, the refrigerant is in a saturated gas state, and its pressure is 0.706MP.
a, The temperature is 38 ° C. The refrigerant is further cooled and condensed under this pressure to reach the state indicated by point d. At this time, the refrigerant is in a saturated liquid state, and its pressure and temperature are the same as the pressure and temperature at point c. The enthalpy at this time is 237.4 kJ / kg.

The refrigerant liquid flowing into the refrigerant passage 143 is decompressed by the throttle 12, and reaches the state at the point e. The pressure at this time is an intermediate pressure between the condensation pressure of the condenser 5 and the evaporation pressure of the evaporator 101, and has a value between 0.262 MPa and 0.706 MPa in the present embodiment. After that, the refrigerant
Evaporating section of the heat exchange section 21 and the second heat exchange section 22
Alternately passes through the condensing section of FIG. 1, passes through the states indicated by points f1, g1, f2, and g2, and is reduced by the restrictor 15 to 0.262 MPa, which is the saturation pressure at a temperature of 8 ° C., and is indicated by the point h. State. The refrigerant in the state at the point h reaches the evaporator 101 as a mixture of a refrigerant liquid and a gas at 8 ° C., where it takes heat from the processing air and evaporates to a saturated gas in the state indicated by the point a. This saturated gas is sucked into the booster 4 again, and the above-described cycle is repeated.

The refrigerant liquid flowing into the refrigerant passage 142 passes through the throttle 11, the evaporating section, the condensing section, and the throttle 14, and passes through the states indicated by points j, i1, k1, i2, and k2 to reach the point. The state shown by l is reached. The refrigerant in the state indicated by the point l reaches the evaporator 101, where it takes heat from the processing air and evaporates to the state indicated by the point q. On the other hand, the refrigerant liquid flowing into the refrigerant path 144 is
3, through the evaporating section, the condensing section, and the throttle 16, and reach the state indicated by the point p through the states indicated by the points m, n1, o1, n2, and o2.

The refrigerant in the state indicated by the point p is supplied to the evaporator 10
1 where heat is removed from the process air and evaporated to a point r
The state shown by. The refrigerant in the state indicated by the point r is
The pressure is increased by the ejector 8 installed in the refrigerant path 142. That is, in the ejector 8, the high-pressure refrigerant in the state indicated by the point q raises the pressure of the low-pressure refrigerant in the state indicated by the point r. As a result, the refrigerant in the state indicated by the point r and the refrigerant in the state indicated by the point q become saturated gas in the state indicated by the point a. As described above, since the operating temperature of the evaporator is increased by installing the ejector 8, the theoretical refrigerating effect is increased, the theoretical compression work is reduced, and the efficiency can be increased. Also, since the specific volume of the refrigerant decreases,
The flow rate of the refrigerant sucked by the booster increases. Therefore, the amount of dehumidification increases with an increase in the freezing effect, and the efficiency can be improved.

Here, the booster 4, the condenser 5, the throttles 11 to 11
Considering the compression heat pump HP2 including the evaporator 16 and the evaporator 101, when the heat exchanger 2 according to the present invention is not provided, the refrigerant in the state of the point d in the condenser 5 is returned to the evaporator 1 via the throttle. Therefore, the enthalpy difference available in the evaporator 101 is 396.8-237.4 = 159.4 kJ.
/ Kg only. However, when the heat exchanger 2 according to the present invention is provided, 396.8-209.5 = 187.3k.
J / kg, and the amount of gas circulating through the compressor for the same cooling load, and thus the required power, is reduced by 15% (= 1-15)
9.4 / 187.3) can also be reduced. That is, the same operation as in the subcool cycle can be provided.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and may be embodied in various forms within the scope of the technical idea. For example, the number of evaporating sections in the first heat exchange section and the number of condensing sections in the second heat exchange section in each branch refrigerant path are not limited to those illustrated. Further, regarding the order of the refrigerant paths in the heat exchanger, the first heat exchange unit at the inlet of the heat exchanger in the above-described embodiment is replaced with the second heat exchange unit,
The number of passes can be increased in the order of the second heat exchange section, the first heat exchange section, and the second heat exchange section. Further, in the above-described embodiment, the dehumidifying air-conditioning device for air-conditioning the air-conditioned space has been described as an example. However, the present invention is not necessarily limited to the air-conditioned space, and the dehumidifying device of the present invention can be applied to other spaces requiring dehumidification. it can.

[0057]

As described above, according to the present invention, the low heat source fluid can be pre-cooled in the first heat exchange means before cooling in the evaporator, and the cooling in the evaporator is performed by using the heat of the pre-cooling. After that, the low heat source fluid can be heated in the second heat exchange means, so that a heat pump having a high operation coefficient can be provided. In addition, if the processing air is used as a low heat source and the processing air is cooled below the dew point temperature by the evaporator,
It is possible to provide a dehumidifying air conditioner having a small energy consumption per dehumidifying amount. Further, by providing the branch refrigerant path, the operating temperature of the refrigerant can be changed stepwise, so that the heat exchange efficiency can be increased.

[Brief description of the drawings]

FIG. 1 is a diagram showing an overall configuration of a system according to the present invention.

FIG. 2 is a diagram schematically showing a flow in the dehumidifying air conditioner according to the first embodiment of the present invention.

FIG. 3 is an enlarged view showing a branch refrigerant path in a heat exchanger of the dehumidifying air conditioner of FIG.

FIG. 4 is a perspective view showing an arrangement of a heat exchanger and an evaporator when a refrigerant path is not branched.

FIG. 5 is a refrigerant Mollier diagram of a heat pump included in the dehumidifying air conditioner of FIG. 2;

FIG. 6 is a psychrometric chart showing an air conditioning cycle in the dehumidifying air conditioner of FIG.

FIG. 7 is a graph showing the relationship between the number of rows of branch refrigerant paths and temperature efficiency in the dehumidifying air conditioner according to the present invention.

FIG. 8 is a diagram schematically showing a flow in a dehumidifying air conditioner according to a second embodiment of the present invention.

FIG. 9 is a refrigerant Mollier diagram of a heat pump included in the dehumidifying air conditioner of FIG.

FIG. 10 is a diagram schematically showing a flow in a conventional dehumidifying air conditioner.

FIG. 11 is a refrigerant Mollier diagram of a heat pump included in a conventional dehumidifying air conditioner.

FIG. 12 is a psychrometric chart showing an air conditioning cycle in a conventional dehumidifying air conditioner.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 101 Evaporator 2 Heat exchanger 3, 6 Blower 4 Booster 5 Condenser 7 Drain pan 8 Ejector 10 Indoor unit 11-16 Throttle 20 Outdoor unit 21 First heat exchange part 22 Second heat exchange part 30-34 , 40-48, 142-144 Path 51 Evaporation section 52 Condensing section 67-69 Tube 100 Air-conditioned space

[Procedure amendment]

[Submission date] July 2, 2001 (2001.7.2)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claim 1

[Correction method] Change

[Correction contents]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction contents]

[0009]

In order to solve the problems in the prior art, one aspect of the present invention is to provide a booster for increasing the pressure of a refrigerant and to heat the high heat source fluid by condensing the refrigerant. A condenser, an evaporator that evaporates the refrigerant and cools the low heat source fluid, a branch refrigerant path that branches into a plurality of rows between the condenser and the evaporator, and the condenser and the evaporator. A first heat exchanger which is provided in the branch refrigerant path between the condensing pressure of the condenser and the evaporating pressure of the evaporator to evaporate the refrigerant to cool the low heat source fluid .
Heat exchange means, provided between the condenser and the evaporator and in the branch refrigerant path, to condense the refrigerant at a pressure intermediate between the condensation pressure of the condenser and the evaporation pressure of the evaporator. A second heat exchange means for heating the low heat source fluid ,
A heat pump, comprising: a first heat exchange means, a low heat source fluid path connecting the evaporator and the second heat exchange means in this order.

Claims (4)

[The claims] A condenser for condensing the refrigerant to heat a high heat source fluid; an evaporator for evaporating the refrigerant to cool a low heat source fluid; A branch refrigerant path that branches into a plurality of rows with the evaporator; and a branch refrigerant path that is provided in the branch refrigerant path between the condenser and the evaporator, and that condenses pressure of the condenser and evaporates the evaporator. First heat exchange means for evaporating a refrigerant at a pressure intermediate to the pressure to cool the processing air, and provided in the branch refrigerant path between the condenser and the evaporator, Second heat exchanging means for condensing the refrigerant at a pressure intermediate between the condensing pressure of the vessel and the evaporating pressure of the evaporator to heat the processing air; the first heat exchanging means, the evaporator, and the second evaporator. And a processing air path for connecting the heat exchange means in this order. A heat pump characterized by the following. 2. A booster that pressurizes a refrigerant, a condenser that condenses the refrigerant to heat a high heat source fluid, an evaporator that evaporates the refrigerant and cools processing air to a dew point temperature or lower, and a condenser. A branch refrigerant path that branches into a plurality of rows between a vessel and the evaporator; and a branch refrigerant path that is provided between the condenser and the evaporator and in the branch refrigerant path, the condensing pressure of the condenser and the evaporation. First heat exchange means for evaporating the refrigerant at a pressure intermediate to the evaporating pressure of the vessel to cool the processing air, and provided in the branch refrigerant path between the condenser and the evaporator. A second heat exchange means for condensing a refrigerant at an intermediate pressure between the condensation pressure of the condenser and the evaporation pressure of the evaporator to heat the processing air; and the first heat exchange means and the evaporator And the second heat exchange means in this order. A dehumidifying air conditioner comprising a road. 3. The dehumidifying air-conditioning apparatus according to claim 2, wherein the branch refrigerant path extends inside the evaporator in parallel and joins downstream of the evaporator. 4. In the branch refrigerant path, a refrigerant path that exchanges heat with the high-temperature process air passes through a refrigerant path that exchanges heat with the low-temperature process air by the refrigerant that has passed through the refrigerant path. The dehumidifying air conditioner according to claim 3, further comprising an ejector for increasing the pressure.