JP4074487B2 - Dehumidifying air conditioner - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a dehumidifying air conditioner, and more particularly, to a dehumidifying air conditioner having a heat pump having a high coefficient of operation (COP) and having a high dehumidifying capacity per energy consumption.
[0002]
[Prior art]
The configuration of a conventional air conditioning system is shown in FIG. As shown in FIG. 15, a conventional dehumidifying air conditioner includes a compressor 201 that compresses refrigerant, a condenser 202 that condenses the refrigerant compressed by the compressor 201 with outside air OA, and an expansion valve 203 that condenses the condensed refrigerant. The evaporator 204 that depressurizes and evaporates the refrigerant to cool the processing air from the air-conditioned space 100 to the dew point temperature, and the processing air cooled to the dew point temperature is disposed downstream of the condenser 202 and upstream of the expansion valve 203. And a reheater 205 for reheating with the refrigerant. The compressor 201, the condenser 202, the reheater 205, the expansion valve 203 and the evaporator 204 constitute a heat pump HP that pumps heat from the processing air flowing through the evaporator 204 to the outside air OA flowing through the condenser 202. .
[0003]
FIG. 16 is a Mollier diagram of a heat pump HP when HFC134a is used as a refrigerant in a conventional dehumidifying air conditioner. In FIG. 16, 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, the temperature is 5 ° C., and the enthalpy is 400.9 kJ / kg. Point b shows a state where the gas is sucked and compressed by the compressor 201, that is, a state at the discharge port of the compressor 201, and the refrigerant at this time is in a superheated gas state.
[0004]
The refrigerant gas in the state of point b is cooled in the condenser 202 and reaches the state indicated by point c. The refrigerant at this time is in a saturated gas state, the pressure is 0.94 MPa, and the temperature is 38 ° C. The refrigerant is further cooled and condensed under this pressure to reach the state indicated by point d. The refrigerant at this time 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]
The refrigerant liquid is depressurized by the expansion valve 203 and is depressurized to 0.34 MPa, which is a saturation pressure at a temperature of 5 ° C., and reaches a state indicated by a point e. The refrigerant in the state of point e reaches the evaporator 204 as a mixture of a refrigerant liquid and a gas at 5 ° C., takes heat from the processing air in the evaporator 204 and evaporates to become a saturated gas in the state shown by the point a. . This saturated gas is again sucked into the compressor 201, and the above-described cycle is repeated.
[0006]
FIG. 17 is a moist air diagram showing an air conditioning cycle in a conventional dehumidifying air conditioner. In FIG. 17, symbols K, L, and M correspond to the path states denoted by the respective symbols in FIG. As shown in FIG. 17, in the conventional dehumidifying air conditioner, the air (state K) from the conditioned space 100 is cooled to the dew point temperature by the evaporator 204, and the dry bulb temperature is lowered and the absolute humidity is lowered. L is reached. This state L is on the saturation line in the wet air diagram. The air in the state L is reheated by the reheater 205, the dry bulb temperature rises while the absolute humidity is constant, reaches the state M, and is supplied to the conditioned space 100. In this state M, both absolute humidity and dry bulb temperature are lower than in state K.
[0007]
[Problems to be solved by the invention]
However, in the conventional dehumidifying air conditioner described above, since the cooling amount to the dew point is large, about half of the refrigeration effect in the evaporator of the heat pump is consumed to take away the sensible heat load, and the dehumidifying capacity per power consumption ( Dehumidification performance) was low. Further, when a single-stage compressor is used as the compressor of the heat pump, it becomes a compression refrigeration cycle of one-stage compression, has a low operating coefficient (COP), and a large amount of power consumption per dehumidification amount.
[0008]
The present invention has been made in view of the above-described problems of the prior art, and an object thereof is to provide a dehumidifying air conditioner having a high operating coefficient (COP) and a high dehumidifying capacity per energy consumption. To do.
[0009]
[Means for Solving the Problems]
In order to solve such problems in the prior art, a first aspect of the present invention includes a booster that pressurizes the refrigerant, a condenser that condenses the refrigerant and heats the high heat source fluid, and the refrigerant Is provided in a refrigerant path between the condenser and the evaporator, and the condensation pressure of the condenser and the evaporation pressure of the evaporator are First heat exchange means for evaporating the refrigerant at an intermediate pressure to cool the processing air, and provided in a refrigerant path between the condenser and the evaporator, the condensation pressure of the condenser and the evaporation A second heat exchange means for condensing the refrigerant with a pressure intermediate to the evaporation pressure of the evaporator to heat the processing air, the first heat exchange means, the evaporator, and the second heat exchange means. The processing air path connected in this order and the cooling air upstream of the heat exchange means. Provided on a path , Depressurize and expand the refrigerant to evaporate a part of the refrigerant Provided on a refrigerant path downstream of the first throttle means and the heat exchange means. , Depressurize and expand the refrigerant to evaporate a part of the refrigerant A dehumidifying air conditioner comprising a second throttle means, wherein the throttle action of the first throttle means is larger than the throttle action of the second throttle means.
[0010]
The second aspect of the present invention is a pressure booster for boosting the refrigerant, a condenser for condensing the refrigerant to heat the high heat source fluid, and evaporating the refrigerant to cool the processing air to a dew point temperature or lower. An evaporator, a branch refrigerant path branched into a plurality of rows between the condenser and the evaporator, and provided between the condenser and the evaporator and in the branch refrigerant path. A first heat exchange means for evaporating the refrigerant at a pressure intermediate between the condensation pressure of the evaporator and the evaporation pressure of the evaporator to cool the processing air, and the branch between the condenser and the evaporator A second heat exchange means provided in the refrigerant path for condensing the 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 The exchange means, the evaporator, and the second heat exchange means are connected in this order. A process air path provided on an upstream side of the refrigerant passage of the heat exchange means , Depressurize and expand the refrigerant to evaporate a part of the refrigerant Provided on a refrigerant path downstream of the first throttle means and the heat exchange means. , Depressurize and expand the refrigerant to evaporate a part of the refrigerant A dehumidifying air conditioner comprising a second throttle means, wherein the throttle action of the first throttle means is larger than the throttle action of the second throttle means.
[0011]
In these cases, the first throttling means and / or the second throttling means can be an orifice, a capillary tube, or an expansion valve.
[0012]
With this configuration, the processing air can be pre-cooled in the first heat exchange means before cooling in the evaporator, and the second heat exchange means is used after cooling to the dew point temperature in the evaporator using the pre-cooling heat. If the processing air is heated in step 1, it is possible to provide a dehumidifying air conditioner with a small energy consumption per dehumidifying amount.
[0013]
Further, by making the throttling action in the first throttling means provided on the refrigerant path upstream of the heat exchanging means larger than the throttling action in the second throttling means provided on the downstream refrigerant path, the upstream side The refrigerant gas passing through the first throttling means is suppressed to enhance the cooling action of the processing air in the first heat exchanging means, and the second throttling means causes the refrigerant to stay in the refrigerant path in the heat exchanging means. And the heat exchange efficiency in the heat exchange means can be increased.
[0014]
Moreover, in the 2nd aspect of this invention, since the working temperature of a refrigerant | coolant can be changed in steps by providing a branched refrigerant path, it becomes possible to improve heat exchange efficiency. Here, when the heat exchanger inlet temperature of the high temperature fluid is TP1, the outlet temperature is TP2, the heat exchanger inlet temperature of the low temperature fluid is TC1, and the outlet temperature is TC2, the heat exchange efficiency φ is When focusing on the cooling of the fluid, that is, when the purpose of the heat exchange is cooling, φ = (TP1−TP2) / (TP1−TC1), when focusing on the heating of the low temperature fluid, that is, the heat exchange When the purpose is heating, it is defined as φ = (TC2−TC1) / (TP1−TC1).
[0015]
Further, as shown in FIG. 2, for example, the dehumidifying air conditioner according to the third aspect of the present invention includes a booster 4 that boosts the refrigerant; a condenser 5 that condenses the refrigerant and heats the high heat source fluid; An evaporator 1 that evaporates the refrigerant and cools the processing air to the dew point; provided in a refrigerant path between the condenser 5 and the evaporator 1, the condensation pressure of the condenser 5 and the evaporation pressure of the evaporator 1 A first heat exchanging means 21 for evaporating the refrigerant at an intermediate pressure to cool the processing air; and a condensing pressure of the condenser 5 provided in a refrigerant path between the condenser 5 and the evaporator 1. A second heat exchange means 22 for condensing the refrigerant with a pressure intermediate to the evaporation pressure of the evaporator 1 to heat the processing air; a first heat exchange means 21, an evaporator 1 and a second heat exchange means 22 is connected to the processing air path in this order; provided on the refrigerant path upstream of the heat exchanging means. The refrigerant is decompressed and expanded to evaporate a part of the refrigerant A first throttle means 11; provided on a refrigerant path downstream of the heat exchange means; The refrigerant is decompressed and expanded to evaporate a part of the refrigerant And a second throttle means 12; configured so that the dryness on the upstream side of the first throttle means 11 is smaller than the dryness on the upstream side of the second throttle means 12.
[0016]
In the dehumidifying air conditioners of the first, second, and third modes, for example, as shown in FIGS. 12 and 13, the first throttling means 412 and the second throttling means 413 are generated in conjunction with the throttling action. It may be configured. As described above, the diaphragm is typically mechanically interlocked to generate a throttle action. However, the present invention is not limited thereto, and may be electrically interlocked, for example.
[0017]
In the dehumidifying air conditioner, for example, as shown in FIG. 13, the first throttle means 412 and the second throttle means 413 may be configured integrally and driven by one drive source 420. Good. Thus, the term “integral” typically means mechanically.
[0018]
In the dehumidifying air conditioner, for example, as shown in FIG. 13, the first throttle means 412 and the second throttle means 413 may have a needle valve mechanism.
[0019]
Here, for example, as shown in FIG. 13, the needle valve mechanism of the first and second throttle means has needles 412, 413 and valve seats 402, 403 on which the needles are seated, respectively. The diameter d1 of the seating portion of the valve seat 402 of the means 412 may be smaller than the diameter d2 of the seating portion of the valve seat 403 of the second throttling means 413.
[0020]
For example, as shown in FIG. 13, the needle valve mechanisms of the first and second throttle means each have a needle and a valve seat on which the needle is seated, and the apex angle α1 of the needle of the first throttle means. May be smaller than the apex angle α2 of the needle of the second throttle means. In this case, the diameter d1 of the seat portion of the valve seat of the first throttle means is equal to the seat portion of the valve seat of the second throttle means. In some cases, the diameter d2 may be the same as or larger than the diameter d2. In short, it is only necessary that the area of the opening generated as the needle valves of both the throttling means are smaller in the first throttling means than in the second throttling means. Therefore, even if the diameter of the seat portion of the valve seat of the first throttle means is larger than the diameter of the seat portion of the valve seat of the second throttle means, the apex angle α1 of the needle of the needle valve of the first throttle means is As long as it is sufficiently smaller than the second α2.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a first embodiment of a dehumidifying air conditioner according to the present invention will be described with reference to FIGS. 1 to 6. FIG. 1 is a diagram showing an overall configuration of an air conditioning system according to the present invention, and FIG. 2 is a diagram schematically showing a flow in a dehumidifying air conditioner according to a first embodiment of the present invention. The dehumidifying air conditioner in the present embodiment cools the air (treated air) in the air-conditioned space 100 to its dew point temperature and dehumidifies it, and includes a heat pump HP1 inside. The treated air whose humidity has been lowered by the dehumidifying air conditioner is returned to the conditioned space 100, whereby the conditioned space 100 is maintained in a comfortable environment.
[0022]
This dehumidifying air conditioner is a dehumidifying air conditioner capable of dehumidifying operation in which the treated air is cooled to its dew point temperature to remove moisture and then reheated to dehumidify. Here, when "processing air A is cooled to its dew point temperature and dehumidified", the processing air A may be somewhat supercooled, but in this case, it is "cooled below dew point temperature and dehumidified" This concept is also included. In addition, air that has been cooled to the dew point temperature and dehydrated has a lower dew point temperature than the original air, so if you use the original dew point temperature as a reference, it will be `` cooled below the dew point temperature and dehumidified. '' Including.
[0023]
As shown in FIG. 1, the dehumidifying air conditioner basically includes an indoor unit 10 installed in the air-conditioned space 100 and an outdoor unit 20 installed outside (outdoor) the air-conditioned space 100. The indoor unit 10 of the dehumidifying air conditioner includes a refrigerant evaporator 1 that evaporates the refrigerant, a heat exchanger 2 that performs heat exchange between the refrigerant and the processing air, and a blower 3 that circulates the processing air. Yes. The heat exchanger 2 performs heat exchange indirectly between the processing air before and after flowing into the evaporator 1 via a refrigerant, and first heat that evaporates the refrigerant and cools the processing air. An exchange unit 21 and a second heat exchange unit 22 that condenses the refrigerant and heats 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, and a blower 6 that blows cooling air.
[0024]
As shown in FIG. 2, the path through which the processing air flows (processing air path) includes a path 30 connecting the air-conditioned space 100 and the first heat exchange unit 21 of the heat exchanger 2, and a first heat exchange unit. 21, a path 31 connecting the evaporator 1 to the evaporator 1, a path 32 connecting the evaporator 1 and the second heat exchange part 22 of the heat exchanger 2, and a connection between the second heat exchange part 22 and the blower 3. And a path 34 that connects the blower 3 and the air-conditioned space 100. The first heat exchanging part 21 of the heat exchanger 2, the evaporator 1 and the second heat exchanging part 22 of the heat exchanger 2 are sequentially connected by such a processing air path.
[0025]
On the other hand, the refrigerant path includes a path 40 that connects the evaporator 1 and the booster 4, a path 41 that connects the booster 4 and the condenser 5, and a path 42 that connects the condenser 5 and the heat exchanger 2. And a path 43 connecting the heat exchanger 2 and the evaporator 1. Further, in the heat exchanger 2, the refrigerant path passes through the first heat exchange unit 21 and the second heat exchange unit 22, and the refrigerant is evaporated in the first heat exchange unit 21. The evaporation section 61 for cooling the processing air flowing through the first heat exchanging portion 21 is formed by the above, and the processing air flowing through the second heat exchanging portion 22 by condensing the refrigerant in the second heat exchanging portion 22 A condensation section 62 is formed that heats (reheats).
[0026]
In addition, the orifice 11 as the first throttle means is disposed in the refrigerant path 42 on the upstream side of the first heat exchanging part 21 of the heat exchanger 2, and the refrigerant path 43 on the downstream side of the second heat exchanging part 22. Is provided with an orifice 12 as a second throttle means. The opening area of the upstream orifice 11 is smaller than the opening area of the downstream orifice 12, and the throttle action (current reducing action) of the upstream orifice 11 is larger than the throttle action of the downstream orifice 12. It is set to be.
[0027]
Outside air OA as cooling air is introduced into the condenser 5 via a path 46. The outside air OA takes heat from the refrigerant that condenses, and the heated outside air is sucked into the blower 6 via the path 47 and discharged to the outside via the path 48 (EX).
[0028]
FIG. 3 is an enlarged view showing a refrigerant path in the heat exchanger 2 of the dehumidifying air conditioner of FIG. The refrigerant path including the evaporation section 61 and the condensation section 62 passes through the first heat exchange unit 21 and the second heat exchange unit 22 alternately and repeatedly. That is, as shown in FIG. 3, the refrigerant path in the heat exchanger 2 is in order from the condenser 5 side, evaporating section 61a, condensing section 62a, condensing section 62b, evaporating section 61b, evaporating section 61c, condensing section 62c. , A condensing section 62d, an evaporating section 61d, an evaporating section 61e, and a condensing section 62e.
[0029]
Here, the first heat exchanging part 21 for flowing the processing air before passing through the evaporator 1 and the second heat exchanging part 22 for flowing the processing air after passing through the evaporator 1 are separate rectangular parallelepiped spaces. Is housed in. In these rectangular parallelepiped spaces, a plurality of heat exchange tubes are arranged in parallel as refrigerant paths on a plane orthogonal to the air flow. A partition wall 510 and a partition wall 520 are provided adjacent to each other in the first heat exchange unit 21 and the second heat exchange unit 22, and the heat exchange tube passes through the two partition walls 510 and 520. Is provided.
[0030]
The ends of the evaporation section 61b and the evaporation section 61c, and the ends of the evaporation section 61d and the evaporation section 61e are connected by a U tube 63, respectively. Similarly, the end portions of the condensing section 62a and the condensing section 62b and the end portions of the condensing section 62c and the condensing section 62d are also connected by the U tube 64, respectively. With such a configuration, the refrigerant that has flowed from the evaporation section 61 a toward the condensation section 62 a in the refrigerant path 42 is guided to the condensation section 62 b by the U tube 64. 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 63, and further flows into the condensing section 62c. Thus, the refrigerant path in the heat exchanger 2 is constituted by a meandering narrow tube group, and the narrow tube group passes through the first heat exchanging part 21 and the second heat exchanging part 22 while meandering, It comes into contact with high air and low temperature air alternately.
[0031]
As shown in FIGS. 1 and 2, a drain pan 7 is provided inside the indoor unit 10 of the dehumidifying air conditioner. The drain pan 7 is not only located in the evaporator 1 but also below the heat exchanger 2. It is preferable to provide a cover. In the first heat exchanging part 21 of the heat exchanger 2, the processing air is mainly precooled. However, since some moisture may condense here, it is particularly provided below the first heat exchanging part 21. preferable.
[0032]
Next, the flow of the refrigerant between the devices will be described with reference to FIGS. The refrigerant gas compressed by the booster 4 is led 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 the outside air OA as cooling air.
[0033]
The refrigerant liquid exiting the condenser 5 is decompressed and expanded by the orifice 11 provided in the refrigerant path 42, and a part of the refrigerant liquid is evaporated (flashed). The refrigerant in which the liquid and gas are mixed reaches the evaporation section 61a of the first heat exchange unit 21, where the refrigerant liquid flows so as to wet the inner wall of the tube of the evaporation section 61a. Although the liquid phase refrigerant flows into the evaporation section 61a, the refrigerant flowing into the evaporation section 61a may be a refrigerant liquid that is partially vaporized and that contains a slight gas phase. While flowing through the evaporating section 61a, the refrigerant liquid evaporates, the processing air before flowing into the evaporator 1 is cooled (precooled), and the refrigerant itself is heated to increase the gas phase.
[0034]
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 refrigerant liquid that has not evaporated) flows into the condensing section 62a. In the condensing section 62a, the processing air having been cooled and dehumidified by the evaporator 1 and having a temperature lower than that of the processing air in the evaporation section 61a is heated (reheated), and the refrigerant itself is deprived of heat while condensing the gas-phase refrigerant. To the next condensing section 62b. While the refrigerant flows through the condensing section 62b, the refrigerant is further deprived of heat by the low-temperature processing air and further condenses the gas-phase refrigerant.
[0035]
The condensed refrigerant liquid flows into the next evaporation section 61b and the subsequent evaporation section 61c, and 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 condensing section 62c and the condensing section 62d, and the processing air is heated (reheated). In this manner, the refrigerant flows through the refrigerant path in the heat exchanger while repeating the phase change between the gas phase and the liquid phase, and the processing air before being cooled by the evaporator 1 and the absolute humidity by being cooled by the evaporator 1. Heat exchange is indirectly performed with the lowered processing air.
[0036]
The refrigerant liquid condensed in the final condensing section 62e is decompressed and expanded by the orifice 12 arranged on the downstream side of the second heat exchanging section 22, and the temperature is lowered. Then, the refrigerant reaches the evaporator 1 and evaporates in the evaporator 1. The processing air that has passed through the first heat exchange unit 21 is cooled by the heat of evaporation of the refrigerant. The refrigerant evaporated and gasified in the evaporator 1 is guided to the suction side of the booster 4 through the path 40. Then, the above cycle is repeated.
[0037]
Next, the effect | action of heat pump HP1 contained in the dehumidification air conditioning apparatus in this Embodiment is demonstrated. FIG. 4 is a refrigerant Mollier diagram of the heat pump HP1 included in the dehumidifying air conditioner of FIG. In the diagram shown in FIG. 4, HFC134a is used as the refrigerant, and the horizontal axis represents enthalpy and the vertical axis represents pressure. Not only HFC134a but also HFC407C and HFC410A can be used as refrigerants, and when these refrigerants are used, the operating pressure region shifts to a higher pressure side than in the case of HFC134a.
[0038]
In FIG. 4, a point a indicates the state of the refrigerant evaporated in the evaporator 1 of FIG. 2, and the refrigerant at this time is in a saturated gas state. The pressure of the refrigerant is 0.4 MPa, the temperature is 5 ° C., and the enthalpy is 402 kJ / kg. Point b shows a state in which 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 1.0 MPa and is in a superheated gas state. .
[0039]
The refrigerant gas in the state of point b is cooled in the condenser 5 and reaches the state indicated by point c. The refrigerant at this time is in a saturated gas state, the pressure is 1.0 MPa, and the temperature is 40 ° C. The refrigerant is further cooled and condensed under this pressure to reach the state indicated by point d. The refrigerant at this time 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 256 kJ / kg.
[0040]
The refrigerant liquid is depressurized by the orifice 11 to change in an enthalpy and flows into the evaporation section 61 a of the first heat exchange unit 21. The state at this time is indicated by a point e, in which a part of the liquid is 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 0.4 MPa and 1.0 MPa in the present embodiment.
[0041]
In the evaporating section 61a, the refrigerant liquid evaporates under the intermediate pressure, and a state of a point f1 located between the saturated liquid line and the saturated gas line is obtained at the same pressure. In this state, a part of the liquid is evaporated, but a considerable amount of the refrigerant liquid remains. And the refrigerant | coolant of the state shown by the point f1 flows in into the condensation sections 62a and 62b. In the condensing sections 62a and 62b, the refrigerant is deprived of heat by the low-temperature processing air flowing through the second heat exchanging section 22, and reaches the state of point g1.
[0042]
The refrigerant in the state of point g1 flows into the evaporation sections 61b and 61c, where heat is taken away and the liquid phase is increased to reach the state of point f2, and further flows into the condensation sections 62c and 62d. In the condensing sections 62c and 62d, the refrigerant increases the liquid phase and reaches the state of the point g2. The point g2 is located on the saturated liquid line in the Mollier diagram. At this time, the refrigerant pressure is 0.6 MPa, the temperature is 20 ° C., and the enthalpy is 228 kJ / kg. Similarly, evaporation and condensation in the evaporation sections 61d and 61e and the condensation section 62e are repeated, but in the Mollier diagram of FIG. 4, the evaporation sections 61d and 61e and the condensation section 62e are omitted, and the condensation section 62d is replaced by the orifice 12 Is shown as being connected.
[0043]
The refrigerant liquid in the state of the point g2 undergoes an isenthalpy change at the orifice 12, and is reduced to 0.4 MPa, which is a saturation pressure at a temperature of 5 ° C., and reaches a state indicated by the point h. The refrigerant in the state at the point h reaches the evaporator 1 as a mixture of a refrigerant liquid and a gas at 5 ° C., where heat is taken from the processing air and evaporated to become a saturated gas as indicated by the point a. This saturated gas is again sucked into the booster 4, and the above-described cycle is repeated.
[0044]
Thus, in the heat exchanger 2, the refrigerant changes in the evaporation state such as from the point e to the point f 1 or from the point g 1 to the point f 2 in the evaporation section 61, and from the point f 1 to the point g 1 in the condensation section 62. Or since the state of condensation is changed from point f2 to point g2 and evaporative heat transfer and condensation heat transfer are performed, the heat transfer rate is very high and the heat exchange efficiency is high.
[0045]
Here, when considered as a compression heat pump HP1 including the booster 4, the condenser 5, the orifices 11 and 12, and the evaporator 1, when the heat exchanger 2 according to the present invention is not provided, the point d in the condenser 5 is Since the refrigerant in the state is returned to the evaporator 1 through the orifice, the enthalpy difference available in the evaporator 1 is only 402−256 = 146 kJ / kg. However, when the heat exchanger 2 according to the present invention is provided, 402−228 = 174 kJ / kg, and the amount of gas circulating to the compressor with respect to the same cooling load, and thus the required power, is 16% (= 1). -146/174) can also be reduced. That is, it is possible to have the same action as the subcool cycle.
[0046]
FIG. 5 is a moist air diagram showing an air conditioning cycle in the dehumidifying air conditioner of FIG. In FIG. 5, symbols K, L, M, and X correspond to the path states denoted by the respective symbols in FIG. 2.
[0047]
The processing air (state K) from the conditioned space 100 is sent to the first heat exchange unit 21 of the heat exchanger 2 through the processing air path 30 and is cooled to some extent by the refrigerant evaporated in the evaporation section 61. The Since this is preliminary cooling before the evaporator 1 cools to the dew point temperature, it can be called pre-cooling. While being precooled in the evaporating section 61, the processing air reaches a point X on the saturation line while removing moisture to some extent and slightly reducing the absolute humidity. Or it is good also as cooling to the intermediate point of the point K and the point X in a pre-cooling stage. Or it is good also as cooling to the point which moved to the low humidity side somewhat on the saturation line beyond the point X.
[0048]
The processing air pre-cooled by the first heat exchange unit 21 is introduced into the evaporator 1 through the path 31. In the evaporator 1, the processing air is cooled to its dew point temperature by the refrigerant which is depressurized by the orifice 12 and evaporates at a low temperature, and the dry bulb temperature is lowered while lowering the absolute humidity while depriving moisture, and the point L To. In FIG. 5, the thick line indicating the change from the point X to the point L is drawn away from the saturation line for convenience, but actually overlaps the saturation line.
[0049]
The processing air in the state of the point L flows into the second heat exchange part 22 of the heat exchanger 2 through the path 32 and is heated to the point M by the refrigerant condensed in the condensing section 62 while keeping the absolute humidity constant. It reaches. The point M is air having an appropriate relative humidity whose absolute humidity is sufficiently lower than that of the point K and the dry bulb temperature is not too low. The air in the state of point M is sucked by the blower 3 and returned to the conditioned space 100 through the path 34.
[0050]
Here, in the cycle on the processing air side shown on the wet air diagram of FIG. 5, the amount of heat obtained by pre-cooling the processing air in the first heat exchange unit 21, that is, the processing air is reheated in the second heat exchange unit 22. The amount of heat ΔH is the amount of heat recovery, and the amount of heat obtained by cooling the processing air with the evaporator 1 is ΔQ. The cooling effect for cooling the air-conditioned space 100 is Δi.
[0051]
As described above, in the heat exchanger 2, the processing air is precooled by the evaporation of the refrigerant in the evaporation section 61, and the processing air is reheated by the condensation of the refrigerant in the condensation section 62. The refrigerant evaporated in the evaporation section 61 is condensed in the condensation section 62. Thus, heat exchange between the process air before and after being cooled by the evaporator 1 is indirectly performed by the evaporation and condensation action of the same refrigerant.
[0052]
Thus, in the present embodiment, the same refrigerant is used as the heat transfer medium for the evaporator that cools the processing air to the dew point (below), the precooler that precools the processing air, and the reheater that performs reheating. Since the refrigerant system is simplified to a single unit and the pressure difference between the evaporator and the condenser can be used, circulation becomes active, and phase change is performed for heat exchange for precooling and reheating. Since the accompanying boiling phenomenon can be applied, the efficiency can be increased.
[0053]
In the present embodiment, as described above, the opening area of the upstream orifice 11 is smaller than the opening area of the downstream orifice 12, and the throttling action of the upstream orifice 11 is the downstream orifice. It is set to be larger than 12 throttling actions. If the refrigerant gas passes through the orifice 11, the refrigerant gas flows into the evaporation section 61 and dissipates heat here, and the cooling action of the processing air in the evaporation section 61 is lowered. Further, when the opening area of the orifice 12 is reduced (that is, when the throttling action is increased), the refrigerant stays in the heat exchanger 2 located on the upstream side of the orifice 12, and the evaporation section 61 and the condensation section 62 described above. The phase change between and will not be made smoothly. Therefore, in the present embodiment, the evaporation area 61 is suppressed by suppressing the refrigerant gas passing through the upstream orifice 11 by making the opening area of the upstream orifice 11 smaller than the opening area of the downstream orifice 12. In addition, the cooling effect of the processing air in the heat exchanger 2 is enhanced and the refrigerant is prevented from staying in the refrigerant path in the heat exchanger 2 by the downstream orifice 12 to increase the heat exchange efficiency in the heat exchanger 2.
[0054]
FIG. 6 is a graph showing the relationship between the orifice inlet dryness and the refrigerant flow rate ratio per unit area that can pass through the orifice in the dehumidifying air conditioner of FIG. In FIG. 6, the solid line indicates the pressure of 1.0 MPa, that is, the inlet of the upstream orifice 11, and the dotted line indicates the pressure of 0.6 MPa, that is, the inlet of the downstream orifice 12. As shown in FIG. 6, the opening area of the downstream orifice 12 is increased from 1 / 0.7 times to 1 / 0.8 times the opening area of the upstream orifice 11, that is, from 1.25 times to 1.43 times. It is preferable to do.
[0055]
Note that it is not necessary for the downstream orifice and the upstream orifice to have the same inlet dryness. Rather, the inlet dryness of the upstream orifice is preferably smaller than the inlet dryness of the downstream orifice. For example, the former is set to 0.000 to 0.002, and the latter is set to 0.008 to 0.010. This is because evaporation and condensation in the heat exchanger 2 can be reliably performed, and for example, it is easy to prevent the refrigerant liquid from staying in the heat exchanger 2. By appropriately setting the throttling action between the downstream orifice and the upstream orifice, the relationship between the inlet dryness of the upstream and downstream orifices can be made as described above.
[0056]
Next, a second embodiment of the dehumidifying air conditioner according to the present invention will be described in detail with reference to FIGS. FIG. 7 is a diagram schematically showing a flow in the dehumidifying air-conditioning apparatus according to the second embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the member or element which has the same effect | action or function as the member or element in the above-mentioned 1st Embodiment, and the part which is not demonstrated is the same as that of 1st Embodiment. .
[0057]
In the present embodiment, the refrigerant path connecting the condenser 5 and the evaporator 1 is branched into a plurality of rows (three rows in FIG. 7) on the downstream side of the condenser 5, and the branched refrigerant routes 142 to 144 are branched. Is formed. The branched refrigerant paths 142 to 144 merge into one path 145 on the upstream side of the evaporator 1. These branch refrigerant paths 142 to 144 pass through the first heat exchange unit 121 and the second heat exchange unit 122 of the heat exchanger 102, respectively, and in the first heat exchange unit 121, there are refrigerants. The evaporation section 151 for cooling the processing air flowing through the first heat exchanging part 121 is formed by evaporating the refrigerant, and the second heat exchanging part 122 is condensed in the second heat exchanging part 122 by condensing the refrigerant. A condensing section 152 is formed that heats (reheats) the process air flowing through.
[0058]
In addition, in each of the branch refrigerant paths 142 to 144, orifices 111 to 113 are arranged on the upstream side of the first heat exchange unit 121, and orifices 114 to 116 are arranged on the downstream side of the second heat exchange unit 122, respectively. Has been. The opening areas of the upstream-side orifices 111 to 113 are smaller than the opening areas of the downstream-side orifices 114 to 116 in the respective paths, and the throttle action (current reduction action) of the upstream-side orifices 111 to 113 is downstream. It is set to be larger than the throttle action of the side orifices 114 to 116.
[0059]
FIG. 8 is an enlarged view showing branch refrigerant paths 142 to 144 in the heat exchanger 102 of the dehumidifying air conditioner of FIG. The refrigerant path including the evaporation section 151 and the condensation section 152 passes through the first heat exchange unit 121 and the second heat exchange unit 122 alternately and repeatedly. That is, as shown in FIG. 8, the branch refrigerant path 142 includes an evaporation section 161a, a condensation section 162a, a condensation section 162b, an evaporation section 161b, an evaporation section 161c, and a condensation section 162c in this order from the condenser 5 side. Yes. Similarly, the branch refrigerant path 143 includes an evaporation section 163a, a condensation section 164a, a condensation section 164b, an evaporation section 163b, an evaporation section 163c, and a condensation section 164c. The branch refrigerant path 144 includes an evaporation section 165a and a condensation section 166a. , A condensation section 166b, an evaporation section 165b, an evaporation section 165c, and a condensation section 166c.
[0060]
Here, the first heat exchanging part 121 for flowing the processing air before passing through the evaporator 1 and the second heat exchanging part 122 for flowing the processing air after passing through the evaporator 1 are separate rectangular parallelepiped spaces. The evaporator 1 described above is disposed between the first heat exchange unit 121 and the second heat exchange unit 122. In the first heat exchange unit 121 and the second heat exchange unit 122, a plurality of heat exchange tubes are arranged in parallel as refrigerant paths on a surface orthogonal to the flow of the processing air. Between the corresponding sections such as the evaporating section 161a and the condensing section 162a, the evaporating section 161b and the condensing section 162b, and the evaporating section 161c and the condensing section 162c, a tube 167 straddling the evaporator 1 is provided. Are connected to each other. The ends of the evaporation section 161b and the evaporation section 161c, the ends of the evaporation section 163b and the evaporation section 163c, and the ends of the evaporation section 165b and the evaporation section 165c are connected by a U tube 168, respectively. Similarly, the ends of the condensation section 162a and the condensation section 162b, the ends of the condensation section 164a and the condensation section 164b, and the ends of the condensation section 166a and the condensation section 166b are also connected by the U tube 169, respectively.
[0061]
With such a configuration, for example, the refrigerant that has flowed from the evaporation section 161a toward the condensation section 162a in the refrigerant path 142 is guided to the condensation section 162b by the U tube 169. The refrigerant guided to the condensing section 162b further flows into the evaporating section 161b, is introduced into the evaporating section 161c through the U tube 168, and further flows into the condensing section 162c. In this way, the refrigerant path is composed of a meandering narrow tube group, and the narrow tube group passes through the first heat exchanging part 121 and the second heat exchanging part 122 while meandering. Alternating contact with low process air.
[0062]
Next, the flow of the refrigerant between the devices will be described with reference to FIGS. The refrigerant gas compressed by the booster 4 is led 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 the outside air OA as cooling air. The refrigerant liquid exiting the condenser 5 is branched into branch refrigerant paths 142 to 144. Below, it demonstrates centering on the refrigerant | coolant which flows through the refrigerant path 142, and since it is the same as that of the description about the refrigerant | coolant which flows through the other refrigerant paths 143 and 144, it abbreviate | omits.
[0063]
The refrigerant flowing through the branch refrigerant path 142 is decompressed and expanded by the orifice 111, and a part of the refrigerant liquid is evaporated (flashed). The refrigerant in which the liquid and gas are mixed reaches the evaporation section 161a, where the refrigerant liquid flows so as to wet the inner wall of the tube of the evaporation section 161a. A liquid-phase refrigerant flows into the evaporation section 161a, but the refrigerant flowing into the evaporation section 161a may be a refrigerant liquid that is partially vaporized and that includes a slight gas phase. While flowing through the evaporation section 161a, the refrigerant liquid evaporates, the processing air before flowing into the evaporator 1 is cooled (precooled), and the refrigerant itself is heated to increase the gas phase.
[0064]
As described above, since the evaporating section 161a and the condensing section 162a are constituted by a series of tubes, the refrigerant gas evaporated in the evaporating section 161a (and the refrigerant liquid that has not evaporated) flows into the condensing section 162a. In the condensing section 162a, the processing air having been cooled and dehumidified by the evaporator 1 and having a temperature lower than that of the processing air in the evaporation section 161a is heated (reheated), and the refrigerant itself is deprived of heat while condensing the gas-phase refrigerant. To the next condensing section 162b. While the refrigerant flows through the condensing section 162b, the refrigerant is further deprived of heat by the low-temperature processing air and further condenses the gas-phase refrigerant.
[0065]
The condensed refrigerant liquid flows into the next evaporation section 161b and the subsequent evaporation section 161c, and 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 condensing section 162c, and the processing air is heated (reheated). In this way, the refrigerant flows through the branch refrigerant path while undergoing a phase change between the gas phase and the liquid phase, and the processing air before being cooled by the evaporator 1 and the processing being cooled by the evaporator 1 to reduce the absolute humidity. Heat exchange is performed indirectly with air.
[0066]
The refrigerant liquid condensed in the condensing section 162c is decompressed and expanded by the orifice 114 disposed on the downstream side of the second heat exchanging section 122, and the temperature is lowered. Then, it merges with the refrigerant flowing through the other branch refrigerant paths 143 and 144, and the merged refrigerant reaches the evaporator 1 through the path 145. In the evaporator 1, the refrigerant evaporates, and the processing air is cooled by the heat of evaporation. The refrigerant evaporated and gasified in the evaporator 1 is guided to the suction side of the booster 4 through the path 40. Then, the above cycle is repeated.
[0067]
Next, the effect | action of heat pump HP2 contained in the dehumidification air conditioning apparatus in this Embodiment is demonstrated. FIG. 9 is a refrigerant Mollier diagram of the heat pump HP2 included in the dehumidifying air conditioner of FIG. In the diagram shown in FIG. 9, HFC134a is used as the refrigerant, and the horizontal axis represents enthalpy and the vertical axis represents pressure. Not only HFC134a but also HFC407C and HFC410A can be used as refrigerants, and when these refrigerants are used, the operating pressure region shifts to a higher pressure side than in the case of HFC134a.
[0068]
In FIG. 9, the point a shows the state of the refrigerant evaporated in the evaporator 1 of FIG. 7, and the refrigerant at this time is in a saturated gas state. The pressure of the refrigerant is 0.4 MPa, the temperature is 5 ° C., and the enthalpy is 402 kJ / kg. Point b shows a state in which 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 1.0 MPa and is in a superheated gas state. .
[0069]
The refrigerant gas in the state of point b is cooled in the condenser 5 and reaches the state indicated by point c. The refrigerant at this time is in a saturated gas state, the pressure is 1.0 MPa, and the temperature is 40 ° C. The refrigerant is further cooled and condensed under this pressure to reach the state indicated by point d. The refrigerant at this time 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 256 kJ / kg.
[0070]
The refrigerant liquid is divided into branched refrigerant paths 142 to 144 and flows into the heat exchanger 102. First, the refrigerant passing through the refrigerant path 143 will be described. The refrigerant liquid that has flowed into the refrigerant path 143 is depressurized by the orifice 112, undergoes an equal enthalpy change, and flows into the evaporation section 163a of the first heat exchange unit 121. The state at this time is indicated by a point e, in which a part of the liquid is 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 0.4 MPa and 1.0 MPa in the present embodiment.
[0071]
In the evaporating section 163a, the refrigerant liquid evaporates under the intermediate pressure, and a state of a point f1 located between the saturated liquid line and the saturated gas line is obtained at the same pressure. In this state, a part of the liquid is evaporated, but a considerable amount of the refrigerant liquid remains. And the refrigerant | coolant of the state shown by the point f1 flows in into the condensation sections 164a and 164b. In the condensing sections 164a and 164b, the refrigerant is deprived of heat by the low-temperature processing air flowing through the second heat exchanging section 122, and reaches the state of the point g1.
[0072]
The refrigerant in the state of point g1 flows into the evaporation sections 163b and 163c, where heat is taken away to increase the liquid phase to the state of point f2, and further flows into the condensing section 164c. In the condensation section 164c, the refrigerant increases the liquid phase and reaches the state of the point g2. The point g2 is located on the saturated liquid line in the Mollier diagram. At this time, the refrigerant pressure is 0.6 MPa, the temperature is 20 ° C., and the enthalpy is 228 kJ / kg.
[0073]
The refrigerant liquid in the state of the point g2 undergoes an isenthalpy change at the orifice 115, and is reduced to 0.4 MPa, which is a saturation pressure at a temperature of 5 ° C., and reaches a state indicated by the point h. The refrigerant in the state at the point h reaches the evaporator 1 as a mixture of a refrigerant liquid and a gas at 5 ° C., where heat is taken from the processing air and evaporated to become a saturated gas as indicated by the point a. This saturated gas is again sucked into the booster 4, and the above-described cycle is repeated.
[0074]
Similarly, the refrigerant passing through the refrigerant path 142 passes through the orifice 111, the evaporating section, the condensing section, and the orifice 114, and is indicated by the point l through the state indicated by the point j, the point i1, the point k1, the point i2, and the point k2. To the state. The refrigerant passing through the refrigerant path 144 passes through the orifice 113, the evaporation section, the condensation section, and the orifice 116, and reaches the state indicated by the point p through the state indicated by the point m, the point n1, the point o1, the point n2, and the point o2. .
[0075]
In this way, in the heat exchanger 102, the refrigerant undergoes a change in evaporation state such as from the point e to the point f1 or from the point g1 to the point f2 in the evaporation section 151, and from the point f1 to the point g1, in the condensation section 152. Or since the state of condensation is changed from point f2 to point g2 and evaporative heat transfer and condensation heat transfer are performed, the heat transfer rate is very high and the heat exchange efficiency is high.
[0076]
Here, when considering as the compression heat pump HP2 including the booster 4, the condenser 5, the orifices 111 to 116, and the evaporator 1, when the heat exchanger 102 according to the present invention is not provided, the point d in the condenser 5 is Since the refrigerant in the state is returned to the evaporator 1 through the orifice, the enthalpy difference available in the evaporator 1 is only 402−256 = 146 kJ / kg. However, when the heat exchanger 102 according to the present invention is provided, 402−228 = 174 kJ / kg, and the amount of gas circulating to the compressor with respect to the same cooling load, and hence the required power, is 16% (= 1). -146/174) can also be reduced. That is, it is possible to have the same action as the subcool cycle.
[0077]
Since the wet air diagram in the present embodiment is the same as the wet air diagram shown in FIG. 5 in the first embodiment described above, the description thereof is omitted here.
[0078]
As described above, in the heat exchanger 102, the processing air is precooled by the evaporation of the refrigerant in the evaporation section 151, and the processing air is reheated by the condensation of the refrigerant in the condensation section 152. Then, the refrigerant evaporated in the evaporation section 151 is condensed in the condensation section 152. Thus, heat exchange between the process air before and after being cooled by the evaporator 1 is indirectly performed by the evaporation and condensation action of the same refrigerant.
[0079]
Thus, in the present embodiment, the same refrigerant is used as the heat transfer medium of the evaporator that cools the processing air below the dew point, the precooler that precools the processing air, and the reheater that performs reheating. As a result, the refrigerant system is simplified to a single unit, and the pressure difference between the evaporator and the condenser can be utilized, so that circulation becomes active, and boiling with phase change in heat exchange for precooling and reheating. Since the phenomenon can be applied, the efficiency can be increased.
[0080]
In the present embodiment, as described above, the opening area of the upstream-side orifices 111 to 113 in each of the refrigerant paths 142 to 144 is smaller than the opening area of the downstream-side orifices 114 to 116, and the upstream side The orifices 111 to 113 are set to have a larger throttle action than the downstream orifices 114 to 116. As described in the first embodiment, the upstream orifices 111 to 113 are set to be smaller than the opening areas of the downstream orifices 114 to 116 as described above. The refrigerant gas passing through the refrigerant is suppressed to enhance the cooling action of the processing air in the evaporation section 151, and the downstream orifices 114 to 116 prevent the refrigerant from staying in the branch refrigerant path in the heat exchanger 102 and heat. The heat exchange efficiency in the exchanger 2 is increased.
[0081]
In the present embodiment, the example in which the refrigerant paths are branched in three rows has been described. However, the present invention is not limited to this, and the refrigerant paths may be branched in any number of rows. Thus, by providing the refrigerant path branched into a plurality of rows, the working temperature of the refrigerant can be changed stepwise, so that the heat exchange efficiency can be increased.
[0082]
Further, in the present embodiment, an example has been described in which the branched refrigerant paths 142 to 144 branched into a plurality of rows on the downstream side of the condenser 5 are joined to the single path 145 on the upstream side of the evaporator 1. However, the branched refrigerant paths 142 to 144 may be extended to the inside of the evaporator 1 and merged at the downstream side of the evaporator 1.
[0083]
In the first and second embodiments, the example in which the orifice is used as the throttle means provided in the refrigerant path has been described, but it is needless to say that the present invention is not limited to this. For example, a capillary tube or an expansion valve can be used as the throttle means. Hereinafter, an example using a throttle means other than the orifice will be described.
[0084]
FIG. 10 is a diagram schematically showing a flow when a capillary tube is used instead of the orifice in the first embodiment described above. When a capillary tube is used instead of the orifice, the throttle action (current reducing action) of the upstream capillary tube 13 is set to be larger than the throttle action of the downstream capillary tube 14. For example, by changing the length, the inner diameter, and the like of the capillary tubes 13 and 14, the throttle action of the upstream capillary tube 13 can be made larger than the throttle action of the downstream capillary tube 14.
[0085]
FIG. 11 is a diagram schematically showing a flow when an expansion valve is used instead of the orifice in the first embodiment described above. When an expansion valve is used instead of the orifice, an external pressure equalizing temperature expansion valve 15 is provided on the upstream side, and a constant pressure expansion valve 16 is provided on the downstream side. These expansion valves may be electronic. The expansion valve 15 is controlled by the temperature and pressure of the refrigerant flowing through the refrigerant flow path on the downstream side of the evaporator 1, and the expansion valve 15 is dry so that the refrigerant flowing through the refrigerant flow path on the downstream side of the evaporator 1 becomes dry. Is controlled. In this case, the downstream expansion valve 16 is controlled so that its opening area is larger than the opening area of the upstream expansion valve 15, and the throttle action of the upstream expansion valve 15 is the downstream expansion valve 16. It is designed to be larger than the squeezing action.
[0086]
Although one embodiment of the present invention has been described so far, it is needless to say that the present invention is not limited to the above-described embodiment, and may be implemented in various forms within the scope of the technical idea.
[0087]
The fifth embodiment will be described with reference to the flowchart of FIG. This embodiment is different from the first embodiment described with reference to FIG. 2 in that the throttle 11 and the throttle 12 are replaced with an integral expansion valve 400, and the intermediate heat exchanger 2 is replaced with the intermediate heat exchanger 302. It is replaced with. However, as the intermediate heat exchanger, the intermediate heat exchanger 2 may also be used in the present embodiment as in the first embodiment.
[0088]
FIG. 12 is a flowchart of the dehumidifying air conditioner according to the fifth embodiment of the present invention, which includes a heat pump HP3. First, the configuration of the present dehumidifying air conditioner will be described, but the description overlapping with that of the first embodiment will be omitted.
[0089]
In the drawing, the configuration along the path of the processing air from the conditioned space 100 is that the heat exchanger 2 is replaced with 302, that is, the first heat exchanging part 21 is 321 and the second heat exchanging part 22 is 322. Except for the replaced point, it is the same as the first embodiment. Further, the path of the cooling air (outside air) passing through the condenser 5 is not different from that of the first embodiment. Therefore, the description is omitted.
[0090]
Next, the equipment configuration of the heat pump HP3 will be described along the path from the evaporator 1 to the refrigerant. In the drawing, the evaporator 1, the path 40, and the compressor 4, the path 41, and the condenser 5 as a booster for compressing (pressurizing) the refrigerant evaporated into the gas by the evaporator 1 are used in the first embodiment. The form is the same. In the present embodiment, the refrigerant path 342 from the condenser 5 is connected to the integral expansion valve 400. The structure of the integral expansion valve 400 will be described in detail later with reference to cross-sectional views.
[0091]
The path 342 is led to the path 342 </ b> A via the integrated expansion valve 400, and the path 342 </ b> A is connected to the evaporation section 361 of the first heat exchange unit 321. The evaporating section 361 is connected to the condensing section 362 of the second heat exchanging section 322 by a communication pipe 342B.
[0092]
The outlet side of the condensing section 362 is connected to the integral expansion valve 400 by a path 343. The path 343 is led to the path 344 via the integrated expansion valve 400, and the path 344 is connected to the evaporator 1. In this way, the heat pump HP3 is configured.
[0093]
Here, the configuration of the heat exchanger 302 is basically the same as that of the heat exchanger 2 except the points described below.
That is, the evaporation section 361 is formed by a tube meandering in the first heat exchanging part 321, and the condensation section 362 is formed by a tube meandering in the second heat exchanging part 322. This is the same as the embodiment.
[0094]
However, in this embodiment, the evaporation section 361 is connected to the condensation section 362 by the pipe 342B after meandering the first heat exchanging section 321 a plurality of times. The condensing section 362 is connected to the path 343 after meandering the second heat exchanging section 322 a plurality of times.
[0095]
In this way, the evaporation section 321 and the condensation section 322 are formed by a continuous heat transfer tube, and the evaporation section 321 is formed a plurality of times in the first heat exchanging portion 361 (more than 1.5 times, more than one reciprocation, typically If the condensing section 362 is meandered a plurality of times in the second heat exchanging section 322 after sufficiently meandering, that is, after evaporating the refrigerant flowing inside, the evaporating section 321 Since the number of pipes 342B connecting the condensing section 322 is one or the minimum (2 to 4), the first heat exchanging part 321 and the second heat exchanging part 322 can be easily separated from each other. .
[0096]
Further, since the evaporation and condensation are not repeated as frequently between the evaporation section 361 and the condensation section 362 as in the first embodiment, the refrigerant can be sufficiently evaporated in the evaporation section 361. Therefore, there is an advantage that the problem that the refrigerant liquid stays in the heat exchanger 302 hardly occurs.
[0097]
The dehumidifying air conditioner of this embodiment includes a controller 451, a pressure sensor 452 and a temperature sensor 453 installed in the path 40. The pressure sensor 452 detects the pressure in the path 40, that is, the evaporation pressure of the evaporator 1 or the suction pressure of the compressor 4, and the temperature sensor 453 detects the temperature in the path 40, that is, the temperature of the refrigerant evaporated in the evaporator 1. To do. The controller 451 controls opening and closing of the integrated expansion valve 400 based on the pressure and temperature detected by the pressure sensor 452 and the temperature sensor 453. Since the superheat degree of the refrigerant in the path 40, that is, the refrigerant superheat degree evaporated in the evaporator 1 is a function of the pressure and temperature of the refrigerant flowing in the path 40, the controller 451 makes the superheat degree a desired value. Thus, the refrigerant flow rate can be adjusted.
[0098]
The configuration and operation of the integrated expansion valve 400 will be described with reference to the cross-sectional view of FIG. The integrated expansion valve 400 is mounted on one end of a valve body 401 formed with spindle housing chambers 405, 406, and 407, which are hollow portions, a spindle (valve body) 411 housed in the hollow portion, and the valve body 401, A stepping motor 420 is configured to move the spindle 411 in the axial direction thereof. The stepping motor 420 includes a stator 421 and a rotor 422, and the rotation axis of the rotor 422 coincides with the axis of the spindle 411.
[0099]
The valve body 401 is constituted by a columnar or prismatic block, and spindle housing chambers 405, 406, and 407 are formed therein as cylindrical hollow portions. The central axes of the cylinders of the respective spindle storage chambers coincide with each other. The spindle storage chambers 405 and 406 are integral chambers separated by a seal 414A described later.
The inner diameter of the cylindrical spindle storage chamber 407 is larger than the inner diameters of the spindle storage chambers 405 and 406.
[0100]
A valve portion 412 having a taper of angle (vertical angle) α1 is formed at the tip of the spindle 411, and a valve portion 413 having a taper of angle α2 is formed at the opposite end. A valve seat 403 is provided at the boundary between the valve housing side 406 and 407 on the valve body side where the valve portion 413 contacts. But A valve seat 402 is formed at the boundary between the formed valve body 412 on which the valve body 412 comes into contact and the spindle storage chamber 405 and the introduction path that guides the refrigerant from the path 342 to the spindle storage chamber 405.
The diameter of the valve seat 402 is d1, and the diameter of the valve seat 403 is d2. In the present embodiment, d1 <d2 and α1 = α2.
[0101]
A refrigerant path 342 is connected to the valve main body 401 so as to guide the refrigerant to the introduction path connected to the valve seat 402. Similarly, the refrigerant path 342A is led to the valve main body 401 so that the refrigerant is led out from the spindle storage chamber 405, and the refrigerant path 343 is drawn from the spindle storage chamber 407 to the valve main body 401 so that the refrigerant is led to the spindle storage chamber 406. A refrigerant path 344 is connected to the valve body 401 so as to lead out the refrigerant.
[0102]
A seal portion 414 having an outer diameter larger than the outer diameter of the cylindrical portion is formed at a central portion in the axial direction of the spindle 411 and between the valve portion 412 and the valve portion 413. An O-ring (O-ring) groove is dug, and an O-ring 414A as a seal is fitted in the groove.
[0103]
A female screw for a drive screw is cut at the end of the spindle 411 on the valve portion 413 side in the axial direction so as to coincide with the spindle 411 axis. A drive screw (male screw) 423 is engaged with the female screw. The drive screw 423 is connected to the rotor 422 shaft of the stepping motor 420.
[0104]
In the integrated expansion valve 400 having such a configuration, when the stepping motor 420 rotates, the drive screw 423 rotates and the spindle 411 moves in the axial direction. The spindle 411 is guided by the drive screw 423 and the inner surfaces 404 of the spindle storage chambers 405 and 406. The amount of movement of the spindle 411 corresponds to the amount of rotation of the rotor 422. The rotation amount of the stepping motor 420 is determined by a signal from the controller 451 (see FIG. 12). Further, the aperture opening areas of the valve portion 412 and the valve portion 413 are determined according to the amount of movement of the spindle 411. Since the valve portion 412 and the valve portion 413 are formed integrally with the spindle 411, the respective aperture opening areas change in conjunction with each other.
[0105]
That is, the throttling action by both valve portions is generated in conjunction. In other words, both valve portions are integrally formed and driven by a stepping motor 420 as one drive source. In the present embodiment, both valve portions are needle valve mechanisms, in which the diameter d1 of the seating portion of the valve seat 402 on which the valve portion 412 is seated is the valve seat on which the valve portion 413 is seated. It is smaller than the diameter d2 of the seating portion 403. Therefore, when the spindle 411 moves in the axial direction, the increase in the opening area of the valve portion 412 is smaller than that of the valve portion 413. In other words, the throttle action of the valve part 412 is more than the throttle action of the valve part 413. big It changes while maintaining the relationship.
[0106]
In the integrated expansion valve 420, the pressure in the spindle storage chamber 405 is the pressure in the evaporation section 361, and the pressure in the spindle storage chamber 406 is the pressure in the condensation section 362. Therefore, both spindle storage chambers 405, 406 Are substantially the same (only the difference in flow loss between the evaporating section 361 and the condensing section 362), the sealing force of the seal 414A can be very light.
[0107]
According to the present embodiment, since the integrated expansion valve 400 is used, the apparatus can be configured compactly. In addition, since the throttling action can be changed in conjunction, the refrigerant liquid does not stay in the heat exchanger 302 when adjusting the refrigerant circulation amount in the apparatus (so that it can be maintained in an appropriate two-phase state). ), The amount of refrigerant flowing into the heat exchanger 302 and the amount of refrigerant flowing out can be balanced.
[0108]
In the above example, the angle α1 = α2 has been described. However, when the apex angle α1 <α2, d1 = d2 can be set, or conversely, d1> d2. If it does so, arrangement | positioning of the valve part 412 and the valve part 413 can be made reverse to FIG.
In short, the area of the opening generated as both the valve parts 412 and 413 open should be smaller in the valve part 412 than in the valve part 413.
[0109]
As described above, the integrated expansion valve 400 has been described in the case where the evaporation section and the condensation section are configured by a single line path as shown in FIG. 2 or 12, and one integrated expansion valve is installed in the path. However, the present invention is not limited thereto, and as described with reference to FIG. 7, the integral expansion valve 400 may be provided in each of the branched refrigerant paths 142 to 144 branched into a plurality of rows on the downstream side of the condenser 5. Further, when the branch refrigerant paths 142 to 144 are further extended to the inside of the evaporator 1 and merged on the downstream side of the evaporator 1, the integral expansion valve 400 may be provided in each branch path.
[0110]
The sixth embodiment will be described with reference to the flowchart of FIG. Note that most of the reference numerals of the same members as those in the fifth embodiment are omitted. The dehumidifying device of the present embodiment is different from the fifth embodiment in that a bypass path 343A is provided between the path 343 and the path 344. A solenoid valve 343B as a bypass valve is inserted and disposed in the bypass path 343A. The solenoid valve 343B is connected to the controller 451 through a signal circuit.
[0111]
When the solenoid valve 343B is opened, the refrigerant flows bypassing the valve portion 413 (see FIG. 13). Therefore, this is the same as when the valve portion 413 does not perform the throttle action (the throttle degree is zero). That is, the valve portion 413 does not substantially form a throttle. At this time, the valve portion 412 performs a throttling action, and the heat exchanger 302 performs an evaporating action at substantially the same pressure as the evaporator 1. That is, this apparatus acts as a cooling air conditioner.
[0112]
The controller 451 determines whether to select the dehumidifying operation mode or the cooling operation mode based on a signal from a humidity detector (and a temperature detector) (not shown) regarding the processing air from the conditioned space 100, and the determination result In response to this, a signal for instructing opening / closing to the solenoid valve 343B is transmitted. That is, when the humidity is high and the temperature (air temperature) is relatively low, the dehumidifying operation mode is selected, the solenoid valve 343B is closed, and when the temperature is high, the cooling operation mode is selected, and the solenoid valve 343B is opened. Of course, the dehumidification and cooling mode selection may be set manually without using the controller.
[0113]
【The invention's effect】
As described above, according to the present invention, the process air can be pre-cooled in the first heat exchange means before cooling in the evaporator, and the second heat is used to cool the dew point to the second temperature after cooling to the dew point temperature. If the processing air is heated in the heat exchange means, it is possible to provide a dehumidifying air conditioner with a small energy consumption per dehumidifying amount.
Further, by making the throttling action in the first throttling means provided on the refrigerant path upstream of the heat exchanging means larger than the throttling action in the second throttling means provided on the downstream refrigerant path, the upstream side The refrigerant gas passing through the first throttling means is suppressed to enhance the cooling action of the processing air in the first heat exchanging means, and the second throttling means causes the refrigerant to stay in the refrigerant path in the heat exchanging means. And the heat exchange efficiency in the heat exchange means can be increased.
[Brief description of the drawings]
FIG. 1 is a diagram showing an overall configuration of an air conditioning 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 refrigerant path in the heat exchanger of the dehumidifying air conditioner of FIG. 2;
FIG. 4 is a refrigerant Mollier diagram of a heat pump included in the dehumidifying air conditioner of FIG.
FIG. 5 is a moist air diagram showing an air conditioning cycle in the dehumidifying air conditioner of FIG. 2;
6 is a graph showing the relationship between the orifice inlet dryness and the refrigerant flow rate ratio per unit area that can pass through the orifice in the dehumidifying air conditioner of FIG. 2. FIG.
FIG. 7 is a diagram schematically showing a flow in the dehumidifying air conditioner according to the second embodiment of the present invention.
8 is an enlarged view showing a branch refrigerant path in the heat exchanger of the dehumidifying air conditioner of FIG.
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 dehumidifying air conditioner according to a third embodiment of the present invention.
FIG. 11 is a diagram schematically showing a flow in a dehumidifying air conditioner according to a fourth embodiment of the present invention.
FIG. 12 is a diagram schematically showing a flow in a dehumidifying air conditioner according to a fifth embodiment of the present invention.
FIG. 13 is a cross-sectional view of an integral expansion valve.
FIG. 14 is a diagram schematically showing a flow in a dehumidifying air conditioner according to a sixth embodiment of the present invention.
FIG. 15 is a diagram schematically showing a flow in a conventional dehumidifying air conditioner.
FIG. 16 is a refrigerant Mollier diagram of a heat pump included in a conventional dehumidifying air conditioner.
FIG. 17 is a moist air diagram showing an air conditioning cycle in a conventional dehumidifying air conditioner.
[Explanation of symbols]
1 Evaporator
2,102,302 heat exchanger
3, 6 Blower
4 Booster
5 Condenser
7 Drain pan
10 indoor units
11, 111-113 Orifice (first throttle means)
12, 114-116 Orifice (second throttle means)
13, 14 Capillary tube
15, 16 Expansion valve
20 Outdoor unit
21, 121, 321 First heat exchange section
22, 122, 322 second heat exchange section
30-34 Process air path
40-43, 145 Refrigerant path
61, 151, 361 Evaporation section
62, 152, 362 Condensation section
63, 64, 168, 169 tubes
100 Air-conditioned space
142-144 Branch refrigerant path
400 Integrated expansion valve
344 Bypass route
343B Solenoid valve
451 controller

Claims (8)

A booster for boosting the refrigerant;
A condenser for condensing the refrigerant to heat the high heat source fluid;
An evaporator for evaporating the refrigerant and cooling the process air to a dew point;
A first cooling unit is provided in a refrigerant path between the condenser and the evaporator, and evaporates the refrigerant at a pressure intermediate between the condensation pressure of the condenser and the evaporation pressure of the evaporator to cool the processing air. Heat exchange means;
A second refrigerant passage disposed between the condenser and the evaporator, wherein the processing air is heated by condensing the refrigerant with a pressure intermediate between the condensation pressure of the condenser and the evaporation pressure of the evaporator; Heat exchange means;
A processing air path connecting the first heat exchange means, the evaporator, and the second heat exchange means in this order;
A first throttling means provided on a refrigerant path upstream of the heat exchanging means and depressurizing and expanding the refrigerant to evaporate a part of the refrigerant;
Provided on a refrigerant path on the downstream side of the heat exchange means, and a second throttle means for evaporating a part of the refrigerant by decompressing and expanding the refrigerant;
The dehumidifying air conditioner characterized in that the throttle action of the first throttle means is larger than the throttle action of the second throttle means. A booster for boosting the refrigerant;
A condenser for condensing the refrigerant to heat the high heat source fluid;
An evaporator for evaporating the refrigerant and cooling the process air to a dew point;
A branched refrigerant path that branches into a plurality of rows between the condenser and the evaporator;
The process air is provided between the condenser and the evaporator and in the branch refrigerant path, and evaporates the refrigerant at a pressure intermediate between the condensation pressure of the condenser and the evaporation pressure of the evaporator. First heat exchange means for cooling;
It is provided in the branch refrigerant path between the condenser and the evaporator, and condenses the refrigerant with a pressure intermediate between the condensation pressure of the condenser and the evaporation pressure of the evaporator to A second heat exchange means for heating;
A processing air path connecting the first heat exchange means, the evaporator, and the second heat exchange means in this order;
A first throttling means provided on a refrigerant path upstream of the heat exchanging means and depressurizing and expanding the refrigerant to evaporate a part of the refrigerant;
Provided on a refrigerant path on the downstream side of the heat exchange means, and a second throttle means for evaporating a part of the refrigerant by decompressing and expanding the refrigerant;
The dehumidifying air conditioner characterized in that the throttle action of the first throttle means is larger than the throttle action of the second throttle means.   The dehumidifying air conditioner according to claim 1 or 2, wherein the first throttle means and / or the second throttle means are orifices.   The dehumidifying air conditioner according to claim 1 or 2, wherein the first throttling means and / or the second throttling means is a capillary tube.   The dehumidifying air conditioner according to claim 1 or 2, wherein the first throttle means and / or the second throttle means are expansion valves. The first throttling means and the second throttle means is configured to stop action is generated in conjunction, the dehumidifying air-conditioning apparatus according to claim 1 or claim 2. The dehumidifying air conditioner according to claim 6 , wherein the first throttle means and the second throttle means are configured integrally and are driven by a single drive source. The dehumidifying air conditioner according to claim 7 , wherein the first throttle means and the second throttle means have a needle valve mechanism.

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