WO2003104727A1

WO2003104727A1 - Heat pump and dehumidifying air conditioner

Info

Publication number: WO2003104727A1
Application number: PCT/JP2003/007328
Authority: WO
Inventors: 前田　健作
Original assignee: 株式会社荏原製作所
Priority date: 2002-06-10
Filing date: 2003-06-10
Publication date: 2003-12-18
Also published as: JP2004012069A; AU2003242172A1; JP3924205B2

Abstract

A heat pump, comprising a refrigerant booster (260), a refrigerant condenser (220) for heating high heat source fluid (B), a refrigerant evaporator (210) for cooling low heat source fluid (A), a heat exchange means (300) installed between the condenser (220) and the evaporator (210), performing the evaporation and condensation of the refrigerant at an intermediate pressure between the condensing pressure of the condenser (220) and the evaporating pressure of the evaporator (210), cooling the low heat source fluid (A) by an intermediate pressure evaporation, and heating the low heat source fluid (A) by an intermediate pressure condensation, a first restriction mechanism (292) installed between the heat exchange means (300) and the evaporator (210) and allowing to increase and decrease the degree of the restriction thereof, a second restriction mechanism (291) installed between the condenser (220) and the heat exchange means (300), and a first controller (501) increasing and decreasing the flow of the refrigerant passing the evaporator (210) according to an increase and a decrease in the degree of the restriction of the first restriction mechanism (292), wherein the low heat source fluid (A) is formed so as to be cooled by the heat exchange means (300), cooled by the evaporator (210), and heated by the heat exchange means (300) in this order.

Description

Description Heat pump and dehumidifying air conditioner Technical field

The present invention relates to a heat pump and a dehumidifying air conditioner, and more particularly to a heat pump that does not cause a problem in the operation of an evaporator even if the degree of throttle of a throttle mechanism is reduced, and a dehumidifier that can easily cope with both a cooling operation and a dehumidifying operation. It concerns air conditioners. Background art

Conventionally, there has been a dehumidifying air conditioner as shown in FIG. This device comprises a compressor 260 for compressing the refrigerant C, a condenser 220 for condensing the compressed refrigerant C in the outside air B, and an expansion valve with bypass 2 having solenoid pulp for the condensed refrigerant C. The pressure is reduced at 91, and the heat exchanger 300,,, which repeats evaporation and condensation at an intermediate pressure, and the refrigerant C condensed here is depressurized at an expansion valve with a bypass 2992 having a solenoid valve. And an evaporator 210 for evaporating the processing air A from the air-conditioned space 101 to the dew point temperature.

In this device, in the dehumidifying operation mode, the bypass solenoid pulp of the expansion valve 292 is closed, and the evaporation and condensation pressures of the heat exchangers 300,, are reduced by the condensation pressure of the condenser 220 and the evaporator 210. Intermediate pressure of the evaporation pressure. Also, in the cooling operation mode, the heat exchanger 300 is opened by opening the solenoid valve of the expansion valve 292 to make the pressure of the heat exchanger 300 '' equal to the evaporation pressure of the evaporator 210. Operate,, and as part of the evaporator.

Therefore, in the dehumidifying operation mode, the heat exchanger 300 '' Heat exchange is performed between the treated air before and after being cooled to the dew point temperature in 210 using a refrigerant as a medium. In this way, the process air A cooled to the dew point in the evaporator 210 is reheated in the heat exchanger 300 ′ ″.

In the conventional dehumidifying air conditioner described above, the heat transfer area for cooling the processing air during the cooling operation is the total area of the evaporator 210 and the heat exchanger 300 ′ ″. On the other hand, during the dehumidification operation, the evaporator 210 only has a heat transfer area for cooling the processing air to the dew point temperature and removing moisture. Therefore, the evaporation temperature of the evaporator 210 decreases due to the large volume flow rate of the refrigerant (the amount of pressure applied to the compressor) suitable for the cooling operation from the compressor 260, which causes problems such as frost formation. Easy. Further, if the cooling capacity is determined so as to cover the cooling load, the capacity becomes excessively large as compared with the capacity required for the dehumidifying load, and the frequency of starting and stopping of the compressor 260 increases, which causes a problem. Disclosure of the invention

Therefore, an object of the present invention is to provide a heat pump that does not cause a problem in the operation of the evaporator even if the throttle degree of the throttle mechanism is increased or decreased, and a dehumidifying air conditioner that can easily cope with both the cooling operation and the dehumidifying operation. .

To achieve the above object, according to a first aspect of the present invention, a heat pump HP1 includes, as shown in FIG. 1, for example, a booster 260 for increasing the pressure of a refrigerant; And a condenser 220 for heating the high heat source fluid B and evaporating the refrigerant to cool the low mature source fluid A; connecting the condenser 220 and the evaporator 210 The refrigerant is evaporated and condensed at an intermediate pressure between the condensing pressure of the condenser 220 and the evaporating pressure of the evaporator 210 provided in the refrigerant passage that performs the cooling operation. Heat exchange means 300 for cooling and heating the low heat source fluid A by the intermediate pressure condensation; heat exchange Recommendation 28

3 A first throttle mechanism 292 provided in the refrigerant path between the means 300 and the evaporator 210 and capable of increasing and decreasing the degree of throttle; a condenser 220 and heat exchange means 3 A second throttle mechanism 291, which is provided in the refrigerant path between 0 and 0; passes through the evaporator 210 in response to an increase or decrease in the degree of throttle of the first throttle mechanism 292. A first controller for increasing / decreasing the refrigerant flow rate; a low heat source fluid A is provided for cooling in the heat exchange means 300, cooling in the evaporator 210, and heating in the heat exchange means 300; Are received in this order.

The second aperture mechanism can also typically increase or decrease the aperture. The aperture is typically increased or decreased by increasing or decreasing the opening area. For example, the aperture may be increased or decreased by increasing or decreasing the length of the capillary tube or the number of apertures arranged in series. Also, the flow rate of the refrigerant passing through the evaporator is typically increased or decreased by making the rotation speed of the booster driving motor variable. For example, the motor is an inverter motor, and the controller is a controller that adjusts the output frequency of the inverter. If the rotation speed of the booster is changed, for example, if the rotation speed is reduced, the suction volume flow rate (pumping amount) of the booster decreases, and it is possible to prevent the evaporation pressure of the evaporator from becoming too low.

The increase and decrease of the degree of restriction and the increase and decrease of the refrigerant flow rate are typically performed according to the amount of heat transferred from the low heat source fluid to the high heat source fluid.

With this configuration, since the first controller that reduces the flow rate of the refrigerant passing through the evaporator in accordance with the increase or decrease of the throttle degree of the first throttle mechanism is provided, the increase or decrease of the throttle degree of the first throttle mechanism is provided. It is possible to adjust the refrigerant flow rate to match the operation mode corresponding to the above.

Further, according to a preferred aspect of the present invention, in the heat pump,

The throttle degree of the throttle mechanism 292 may be configured to be able to be reduced to a throttle degree sufficient for the intermediate pressure to be substantially the same as the evaporation pressure of the evaporator 210. With this configuration, the degree of throttle of the first throttle mechanism can be reduced to a degree of throttle sufficient to make the above-mentioned intermediate pressure substantially equal to the evaporating pressure of the evaporator. The heat exchange means 300 can be combined with the evaporator 210 to act as a part of the evaporator.

Further, according to a preferred aspect of the present invention, in the heat pump, the first controller 292 is configured to be capable of adjusting the refrigerant flow rate at a maximum set flow rate or less, and the first throttle mechanism 292 is provided. The above-mentioned refrigerant flow rate can be adjusted to be equal to or less than the first set maximum flow rate at the time of the operation at the sufficient throttle degree, and at the time of the operation at which the first throttle mechanism 292 is throttled below the sufficient throttle degree. The coolant flow rate can be adjusted to be equal to or less than a second set maximum flow rate, and the second set maximum flow rate is configured to be smaller than the first set maximum flow rate.

With this configuration, the second set maximum flow rate is smaller than the first set maximum flow rate, so that the refrigerant flow rate does not become excessive when the first throttle mechanism is operated with a sufficient degree of throttle. You can do so.

Further, according to a preferred aspect of the present invention, in the heat pump, the second throttle mechanism 291 is configured so that the degree of throttle can be increased or decreased, and the refrigerant flow rate is equal to or less than the maximum set flow rate. A second controller 501 that increases or decreases according to the degree of aperture of the aperture mechanism 291 may be provided. Here, the first and second controllers may be different controllers or may be configured as the same controller.

Further, according to a preferred embodiment of the present invention, the heat pump includes inverter motors 502, 505 for driving a booster 260; the increase / decrease of the coolant flow * is controlled by the inverter motor 5 Adjust the rotation speed of 02, 505 P03 07328

5 It may be configured to do so.

To achieve the above object, according to a second aspect of the present invention, a dehumidifying air conditioner 21 includes, as shown in FIG. 1, a booster 260 for increasing the refrigerant C; A condenser 220 for condensing and heating the high heat source fluid B; an evaporator 210 for evaporating the coolant C to cool the processing air A to the dew point temperature; a condenser 220 and an evaporator 2 The refrigerant C is evaporated and condensed at an intermediate pressure between the condensing pressure of the condenser 220 and the evaporating pressure of the evaporator 210, which is provided in the refrigerant path connecting the evaporator 210 and the evaporator 210. Heat exchange means 300 for cooling the processing air A by the intermediate pressure condensation, and heating the processing air A by the intermediate pressure condensation; and provided in the refrigerant path between the heat exchange means 300 and the evaporator 210. A first throttle mechanism 292 capable of increasing or decreasing the degree of throttle; and a second throttle provided in the refrigerant path between the condenser 220 and the heat exchange means 300. Structure 291, a first controller 5101 for increasing or decreasing the flow rate of the refrigerant passing through the evaporator 210 in accordance with an increase or decrease in the degree of throttle of the first throttle mechanism 291; Is configured to receive cooling in the heat exchange means 300, cooling in the evaporator 210, and heating in the heat exchange means 300 in this order.

To achieve the above object, according to a third aspect of the present invention, a dehumidifying air conditioner 21 includes, as shown in FIG. 1, a booster 260 for increasing the refrigerant C; A condenser 220 for condensing and heating the high heat source fluid B; an evaporator 210 for evaporating the coolant C to cool the processing air A to the dew point temperature; a condenser 220 and an evaporator 2 The refrigerant C is evaporated and condensed at an intermediate pressure between the condensing pressure of the condenser 220 and the evaporating pressure of the evaporator 210, which is provided in the refrigerant path connecting the evaporator 210 and the evaporator 210. A heat exchange means for cooling the processing air A before entering the evaporator 210 by heating the air after leaving the evaporator 210 by the intermediate pressure condensation; and a heat exchange means. 3 0 0 The first operation mode in which the treated air A is cooled by the heat exchange means 300 and then the heat exchange means 300 is switched so that the refrigerant C is evaporated at substantially the same pressure as the evaporator 210. And a second operation mode for cooling the processing air A is configured to be switchable; and a first controller 50 for increasing or decreasing the flow rate of the refrigerant passing through the evaporator 210 in response to the switching of the operation mode. With 1. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a flowchart of a dehumidifying air conditioner according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing the configuration of the controller shown in FIG.

3A to 3C are a schematic side view and a perspective view of a heat exchanger showing an installation state of the dehumidifying air conditioner shown in FIG.

FIG. 4 is a Mollier diagram of the heat pump of the dehumidifying air conditioner shown in FIG. FIG. 5 is a bar graph illustrating the relationship between the dehumidification load and the cooling load. FIG. 6 is a psychrometric chart illustrating the operation of the dehumidifying air conditioner of FIG. 1 in the dehumidifying operation mode.

FIG. 7 is a partial flow chart of the dehumidifying air conditioner according to the second embodiment of the present invention.

8A and 8B are a schematic side view showing a state of installation of the dehumidifying air conditioner shown in FIG. 7 and a perspective view of a heat exchanger.

FIG. 9 is a Mollier diagram of the heat pump of the dehumidifying air conditioner shown in FIG. FIG. 10 is a flowchart of a conventional heat pump and a dehumidifying air conditioner. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each of the drawings, the same or corresponding members are denoted by the same or similar reference numerals, and redundant description is omitted.

FIG. 1 is a flow chart of a heat pump HP1 according to a first embodiment of the present invention and a dehumidifying air conditioner 21 provided with the heat pump HP1 as an example of the dehumidifying air conditioner of the present invention. The dehumidifying air conditioner 21 is a dehumidifying air conditioner 21 that cools the processing air A to its dew point temperature, removes moisture, reheats and dehumidifies by reheating, and a cooling operation that mainly removes sensible heat. Here, when "processing air A is cooled to its dew point temperature and dehumidified", processing air A may be slightly overcooled, but in this case, it is "cooled to dew point temperature or less and dehumidified". However, this concept is also included. In addition, air that has been cooled to the dew point temperature to remove moisture has a lower dew point temperature than the original air.Therefore, based on the initial dew point temperature, it is `` cooled below the dew point temperature and dehumidified ''. Including just in case.

The configuration of the heat pump HP 1 according to the first embodiment and the dehumidifying air conditioner 21 including the same will be described with reference to FIG. In the dehumidifying air conditioner 21, the evaporator 210 lowers the humidity of the processing air A as a low heat source fluid, and maintains the air-conditioned space 101 to which the processing air A is supplied in a comfortable environment.

In the figure, the processing air-related equipment configuration will be described along the route of the processing air A from the air-conditioned space 101. First, the path 107 connected to the air-conditioned space 101, the first section 310 of the heat exchanger 300 as a heat exchange means, the path 108, and the processing air A are kept below their dew point temperature. Evaporator to be cooled 210, route 1 109, connected to second section 3200 of heat exchanger 300, route 110, route 110 A blower 102 for circulating the processed air A is arranged in this order with a path 111, and is configured to return to the air-conditioned space 101. In the figure, the air supplied from the dehumidifying air conditioner 21 to the air conditioning space 101 is indicated by SA, and the air returning from the air conditioning space 101 to the dehumidifying air conditioner is indicated by.

In addition, along the path of cooling air (outside air) B as a high heat source fluid from the outdoor OA, path 124, condenser 220 for cooling and condensing refrigerant C, path 125, and cooling air B are blown. The air blower 140 and the path 126 are arranged in this order, and are configured to discharge the exhaust air EX to the outdoor OA.

Next, the equipment configuration of the heat pump HP1 will be described along the path of the refrigerant C from the evaporator 210. In the figure, the evaporator 210, route 204, compresses the refrigerant C evaporated and gasified in the evaporator 210 (pressurizes). Compressor 260 as a booster, route 201, condenser 2 20, path 202, restrictor 330, evaporator section 251, which cools process air A flowing through first section 310 of heat exchanger 300, second section 320 of heat exchanger 300 Flowing process The heat pump HP 1 is constructed in such a way that the condensing section 25 2 which heats (reheats) the air A, the path 203 and the throttle 250 are arranged in this order, and returns to the evaporator 210 again. ing.

The evaporating section 25 1 is formed by a tube meandering in the first section 310, and the condensing section 25 2 is formed by a tube meandering in the second section 320. In the present embodiment, the evaporating section 25 1 is connected to the condensing section 252 after meandering the first section 3 10 several times. The condensing section 25 2 is connected to the path 203 after meandering the second section 320 multiple times. In the figure, each section is shown to meander in a plane along the flow of the processing air A, but the flow of the processing air A is actually It is better to meander in a plane perpendicular to the plane (see Fig. 3B and Fig. 3C). However, a plurality of orthogonal surfaces may be provided so that there are a plurality of meandering layers.

In this way, the evaporating section 25 1 and the condensing section 25 2 are formed by a continuous heat transfer tube, and after the evaporating section 25 1 is fully meandered several times in the first section 3 10, If the condensing section 255 is meandered several times in the second section after evaporating the flowing refrigerant, the number of pipes connecting the evaporating section 251 and the condensing section 252 is one or a minimum. (2 to 4) is enough, so it is easy to install the first section 310 and the second section 320 separately (see Figs. 3B and 3C).

A path 202 A for bypassing the throttle 330 is provided in the path 202 of the refrigerant C, and a throttle 335, solenoid pulp and 336 are provided in series in the path 202A. In addition, a path 203 A that bypasses the throttle 250 is provided in the path 203 of the refrigerant C, and a solenoid valve 25 3 is provided in the path 203 A. The second throttle mechanism 291, including the aperture 330, the aperture 335, and the solenoid valve 336, is configured. The first aperture mechanism 292, including the aperture 250 and the solenoid valve 25, is formed. It is configured. When the solenoid pulp 253 is opened, the opening area is formed so as to be approximately equal to the cross-sectional area of the passage 203. In other words, when the solenoid valve 25 3 is opened, the aperture of the first aperture mechanism 292 is reduced (the aperture area is increased), and an aperture that is so large that it does not substantially act as an aperture is provided. Will have.

When the solenoid valve 3336 is opened, the second diaphragm mechanism 291 forms a diaphragm having a large opening area (the opening area of the diaphragm 330 and the opening area of the plus diaphragm 335). At this time, the aperture of the second aperture mechanism decreases That is, the opening becomes large. When the solenoid pulp 336 is closed, the second diaphragm mechanism 291 forms a diaphragm having a small opening area (the opening area of the diaphragm 330). At this time, the degree of aperture of the second aperture mechanism is increased and good! The aperture is smaller.

In other words, when the solenoid pulp 25 3 is opened, the opening area of the first drawing mechanism 29 2 becomes large, and the first drawing mechanism 29 2 is set so that it does not substantially form a drawing. You. When the solenoid pulp 25 3 is closed, the opening area of the first aperture mechanism 29 2 is reduced, and the first aperture mechanism 29 2 is set to form an aperture.

Here, the configuration of the heat exchanger 300 will be described. The heat exchanger 300 is a heat exchanger that indirectly exchanges heat between the treated air A before and after flowing into the evaporator 210 via the refrigerant C.

The heat exchanger 300 has a first section 310 for flowing the processing air A before passing through the evaporator 210 and a second section 310 for flowing the processing air A after passing the evaporator 210. The two sections 320 form separate rectangular parallelepiped spaces. Both compartments are provided with partitions 301 and 302 so that the processing air flowing through both compartments is not mixed, and connect the evaporating section 251, which is a heat exchange tube, to the condensing section 252 The pipe 202B penetrates the partition walls of these two sections.

In the figure, the treated air A before being introduced into the evaporator 210 is supplied to the first section 310 from the right through the path 107 and from the left through the path 108 from the left. get out. In addition, treated air A, which has been cooled to the dew point temperature (below) through the evaporator 210 and has a reduced absolute humidity, is supplied from the left side in the figure to the second section 320 through the path 109, and from the right side. Exit through Route 1 110. The dehumidifying air conditioner 21 according to the present embodiment is configured such that the return air RA has a wet passage 107. A temperature detector 503 and a temperature detector 504 are provided. The compressor 260 is configured to be driven by an AC motor 505, and the AC motor 505 is supplied with AC power from an impeller 502, which is a frequency converter. Further, a controller 501 for controlling the dehumidifying air conditioner 21 is provided.

The controller 501 is connected to the humidity detector 503, temperature detector 504, inverter 505, and solenoid valves 253, 336 via signal wiring.

The controller 501 will be described with reference to the block diagram of FIG. The controller 501 may be constituted by a so-called microphone computer. The controller 501 includes a control section 501A and a memory section 501D. The control unit 501A includes a mode selection module 501B and an impeller control module 501C.

The mode selection module 503 B determines whether to select the dehumidification operation mode or the cooling operation mode based on the signal from the humidity detector 503 and the signal from the temperature detector 504, and makes the determination. According to the result, a signal for opening and closing is transmitted to the solenoid pulp 253 and 336. That is, when the humidity is high and the temperature (air temperature) is relatively low, the dehumidifying operation mode is selected, the solenoid pulp 253 is closed, and the solenoid valve 336 is closed. When the solenoid pulp 253 is closed, the refrigerant pipe between the heat exchanger 300 and the evaporator 210 is connected via the throttle 250 and the heat exchanger 300 The evaporating pressure and the condensing pressure at become the intermediate pressure.

If the temperature (air temperature) is relatively high, select the cooling operation mode and open the solenoid valves 2 5 3 and 3 6. Especially in Japan, when the temperature is high, the absolute humidity is usually high. In this case, it is better to select the cooling operation mode and actively remove both sensible heat and latent heat. 12., Note that the selection of the dehumidifying operation mode and the cooling operation mode may be performed manually without depending on the mode selection module. High and low humidity also have personal preferences. Also, regardless of the humidity or temperature, there may be cases where it is desired to forcibly lower the temperature anyway, or for simply drying the room in order to lower the humidity anyway.

When the solenoid pulp 253 is opened, the refrigerant pipe between the heat exchanger 300 and the evaporator 210 is connected substantially without restriction, and the inside of the heat exchanger 300 The pressure inside the heat transfer tube is substantially equal to the evaporation pressure of the evaporator 210 in both the evaporator section 25 1 and the condensing section 25 2. Acts as an evaporator.

The inverter control module 501C adjusts the frequency of the inverter 502. The maximum rotation speed of the AC motor 505 is stored in the memory section. This value can be freely changed and set from a maximum rotation speed setting input unit (not shown) provided in the controller 501.

When the mode is selected, the mode selection module 501 0 stores the maximum rotation speed 501 0 in the dehumidifying operation mode or the maximum rotation speed 501 0F in the cooling operation mode according to the selected mode. Read from section 501 D to specify. The inverter control module 501C adjusts the frequency output of the inverter 502 with the specified maximum rotation speed as an upper limit. That is, the rotation speed of the motor 505 is adjusted. By this adjustment, the displacement of the refrigerant of the compressor 260 (when the compressor is a reciprocating compressor having a piston, the displacement is determined by the volume and rotation speed of one stroke of the biston). Can be adjusted with the maximum flow rate during dehumidification, which is the second maximum flow rate, as the upper limit. Similarly, in the cooling operation mode, the amount of refrigerant to be pushed by the compressor 260 can be adjusted with the first maximum flow rate, which is the maximum flow rate during cooling, as the upper limit. Dehumidifying operation mode The maximum rotation speed in the cooling operation mode is set to be lower than the maximum rotation speed in the cooling operation mode. In this case, the mass flow rate of the refrigerant is adjusted in accordance with the adjustment of the amount of award.

In this way, for example, in the operation in the dehumidifying operation mode, the opening degree (reciprocal of the degree of throttling) corresponding to the degree of throttling of the throttling mechanism 292 is reduced, and the amount of displacement of the refrigerant of the compressor 260 is reduced. Since the pressure is reduced to reduce the evaporation pressure of the evaporator 210, it is possible to prevent the evaporator 210 from lowering, and to prevent, for example, frost on the evaporator 210. In other words, the amount of displacement of the compressor 260 may increase or decrease in accordance with the operation mode.

The compressor 260 operates at a constant rotational speed at the maximum rotational speed of each operation mode, stops cooling when it is too cold in the cooling operation mode, and stops when it is too dry in the dehumidification operation mode. Off operation may be performed, or the maximum rotation speed may be set as the upper limit, and the rotation speed may be set so that the temperature becomes a predetermined set value in the cooling operation mode and the humidity becomes the predetermined set value in the dehumidification operation mode. May be controlled.

Although the valve 336 has been described as an on / off solenoid valve, it may be a control valve capable of adjusting the degree of throttling according to a cooling load or a dehumidifying load. At this time, the aperture 3 3 5 is not necessary.

The compressor 260 is a positive displacement compressor driven by an electric motor with variable rotation speed (for example, a reciprocating type having a piston and a cylinder), and increases or decreases the rotation speed to increase or decrease the flow rate of the refrigerant. Although it has been described as having a plurality of cylinders, the number of cylinders to be used may be increased or decreased to increase or decrease the amount of coolant supplied. It is also possible to provide a plurality of compressors and adjust them by increasing or decreasing the number of operating units. For larger dehumidifying air conditioners, centrifugal compressors are used, It may be adjusted by a damper or inlet damper control.

Next, referring to the schematic side view showing the installation state of the dehumidifying air conditioner in FIG. 3A and the perspective views of the heat exchanger in FIGS. 3B and 3B, the evaporator 210 and the heat exchanger 30 A configuration example of 0 will be specifically described. As shown in Fig. 3B and Fig. 3C, the evaporating section 251, which is composed of heat transfer tubes (capillaries), is arranged to penetrate many plate fins. They are connected to each other by U-tubes outside the outermost fins. In this way, the heat transfer tube penetrates the first section 310 multiple times while meandering.

The first section 310 is a rectangular parallelepiped space formed by arranging a large number of rectangular plate fins in parallel. Further, it is preferable that the outer surface of the rectangular parallelepiped space for accommodating the plate fin and the thin tube group is surrounded by a plate housing. However, two opposing surfaces of the housing are open, and the processing air passes through the openings.

Similarly, the condensing section 25 2, which is a heat transfer tube, penetrates the second section 3 20 several times in a meandering manner. The second section 320 is also a rectangular parallelepiped space having the same structure as the first section 310.

The end of the evaporating section 25 1 and the end of the condensing section 25 2 are connected by a pipe 202B. In the present embodiment, the pipe 202B is configured as a part of a continuous tube forming the evaporating section 251 and the condensing section 252.

As described above, the evaporating section 251, which is the refrigerant flow path, and the condensing section 255, respectively, constitute a meandering narrow tube group. In this manner, the refrigerant C flowing in one direction as a whole from the evaporating section 25 1 to the condensing section 25 2 flows in a meandering manner in the group of small tubes while evaporating. While evaporating in Chillon 25 1 and condensing in condensing section 25 2, heat from the hot process air A flowing through the first compartment 310 is transferred to the cooler air flowing through the second compartment 320. Inform process air A.

Similarly, the evaporator 210 also has a heat transfer tube formed through a number of rectangular plate fins. The configuration is configured as a rectangular parallelepiped space like the first section 310 and the second section 320. They are connected by U-tubes outside the outermost fins. In this way, the heat transfer tube penetrates the fin several times while meandering.

In the present embodiment, the evaporating section 25 1 and the condensing section 25 2 are each configured as a single-layer thin tube group arranged in a meandering manner in one plane orthogonal to the flow of the processing air A. On the other hand, the evaporator 210 is configured as a two-layered thin tube group arranged in a meandering manner in two planes orthogonal to the flow of the processing air A. However, the number of layers is not limited to this, and may be determined according to the amount of heat transfer. In addition, the distribution of the heat transfer area of the thin tube group in the heat exchanger 300 and the evaporator 210 may be determined according to the ratio between the latent heat load and the sensible heat load, as described later.

Further, the evaporator 210 is disposed between the first section 310 and the second section 320. With this arrangement, by split one rectangular spaces 3, respectively a first compartment 3 1 0, the evaporator ² 1 0, can be configured as a second compartment ³ 2 0, structure Becomes simple. It is preferable that the fins are cut so as to be discontinuous as shown in the drawing between each of the sections 310, 320 and the evaporator 210. This is because the temperature of each adjacent part is different.

In this configuration, the tubules are pierced at equal intervals through And each tube is connected by a simple U-tube, and one or a few pipes (or tubes) are connected between each section 310 and 320 and between the evaporators 210. The configuration is simple and the manufacturing is easy because it is only necessary to connect with a part). Next, an example in which the above-described dehumidifying air conditioner is applied as an air conditioner of the air-conditioned space 101 will be described with reference to the schematic cross-sectional view of FIG. 3A. In the air-conditioned space 101, that is, in the indoor unit installed indoors, a heat exchanger assembly comprising a first section 310, an evaporator 210, and a second section 320 And a blower 102 for circulating the return air RA and the supply air SA. If a cross flow fan is used as the blower 102, the indoor units can be compacted. A dust filter is provided on the upstream side of the flow of the return air RA in the first section 310.

A drain pan 450 is provided below the heat exchanger 300 and the evaporator 210. From the drain pan 450, a drain pipe is led outside.

Return air RA is filtered through a filter, pre-cooled in the first section 310, further cooled in the evaporator 210 and dehumidified to saturated air. This saturated air is reheated in the second section 320 and supplied to the air-conditioned space 101 by the blower 102 as supply air SA having an appropriate absolute humidity and an appropriate temperature, that is, an appropriate relative humidity. Is done. In other words, the treated air is pre-cooled while passing in one direction through a mass of plate fins and small tubing that looks like a normal cooling fin tube heat exchanger (although there is a gap between each section and the evaporator). , Moisture removal and reheating are all performed at once, resulting in supply air SA with appropriate humidity and temperature.

A condenser 220, a compressor 260, and a blower 140 are housed in an outdoor unit installed outside the air-conditioned space 101. Then, the condenser 220 and the evaporating section 25 1 of the first section 310 are connected by a pipe 202, and the evaporating The unit 210 and the compressor 260 are connected by a pipe 203. That is, the indoor unit and the outdoor unit are connected only by two pipes 202 and 203. In this drawing, the aperture mechanisms 29 1 and 29 2 are not shown.

Next, referring first to FIG. 1, the flow of the refrigerant C between the respective devices will be described.

The operation of the heat pump HP 1 will be described with reference to a refrigerant Mollier diagram in a dehumidifying operation mode as a first operation mode of the heat pump HP 1. In FIG. 1, the case of the dehumidification operation mode as the first operation mode will be described first. At this time, the solenoid pulp 336 is closed and the solenoid pulp 253 is also closed. The refrigerant gas C compressed by the compressor 260 is guided to the condenser 220 via a refrigerant gas pipe 201 connected to a discharge port of the compressor 260. The refrigerant gas C compressed by the compressor 260 is cooled and condensed by the outside air B as cooling air.

The refrigerant outlet of the condenser 220 is connected to the inlet of the evaporating section 25 1 of the heat exchanger 300 by a refrigerant path 202. In the middle of the refrigerant path 202, near the entrance of the evaporating section 251, a throttle 330 is connected to the refrigerant path 202, and a bypass path 202A that bypasses the refrigerant path restriction 330. Has a throttle 335 and a solenoid pulp 336 connected in series, and the solenoid valve 336 is closed. The reason why the solenoid pulp 336 is closed is that the required refrigerant flow rate is usually smaller in the dehumidifying operation mode than in the cooling operation mode, as described later.

The liquid refrigerant C that has exited the condenser 220 is depressurized by the throttle 330, expands, and a part of the refrigerant C evaporates (flashes). The refrigerant C mixed with the liquid and the gas reaches the evaporating section 251, where the liquid refrigerant C penetrates the plate fin and wets the inner wall of the meandering evaporating section 251 tube. The treated air A that flows and evaporates in the first section 310 before flowing into the evaporator 210 is cooled (precooled).

The refrigerant, which has been evaporated to some extent in the evaporating section 251, and has become a mixture of gas and liquid, is led to the pipe 202B and flows into the condensing section 2552. Process air A flowing through the second section 320, that is, pre-cooled in the first section 310, cooled and dehumidified in the evaporator 210, and has a lower temperature than before flowing into the evaporator 210 The treated air A is heated (reheated), and the refrigerant itself is deprived of heat and condensed. In the present embodiment, the evaporating section 25 1 and the condensing section 2

52 is formed of a series of tubes (including U tubes). That is, since the refrigerant gas C (and the refrigerant liquid C that did not evaporate) evaporated in the evaporating section 25 1 is configured as an integral flow path, the condensing section

The heat is transferred at the same time as mass transfer by flowing into and condensing into 25 2. The outlet side of the last condensing section 250 of the heat exchanger 300 is connected to the evaporator 210 by a refrigerant liquid pipe 203, and an expansion valve 250 is provided in the refrigerant pipe 203. Also, a solenoid valve 253 that bypasses the expansion valve 250 is provided.

The refrigerant liquid C condensed in the condensing section is decompressed by the throttle 250 and expanded to lower the temperature, enters the evaporator 210 and evaporates, and cools the processing air A by the heat of evaporation. As the throttles 330 and 250, for example, orifices, capillary tubes, expansion valves, and the like are used. Since the solenoid pulp 253 is closed, the refrigerant liquid C does not pass through the solenoid pulp 253. In the dehumidifying operation mode, the controller 501 closes the solenoid valve 25 3 and switches the degree of throttle of the first throttle mechanism 29 2 to an increased value (small opening area). The rotation speed of the drive inverter motor 505 is reduced so as to reduce the amount of the refrigerant of the machine 260. Evaporator 2 1 The evaporation pressure of 0 becomes appropriate, and the refrigerant mass flow rate as the refrigerant flow rate passing through the evaporator also decreases.

The refrigerant C evaporated and gasified by the evaporator 210 is led to the suction side of the compressor 260 through the path 204, and the above cycle is repeated.

In the figure, the behavior of the refrigerant C in the evaporating section 25 1 and the condensing section 25 2 of the heat exchanger 300 will be described. First, the liquid-phase and gas-phase refrigerant C flows into the evaporating section 25 1. Refrigerant liquid C which is partially vaporized and slightly contains a gas phase may be used. While flowing through the evaporating section 251, the refrigerant C pre-cools the processing air A and heats itself, and flows into the condensing section 252 while increasing the gas phase. The condensing section 255 heats the processing air A, which has a lower temperature than the processing air A in the evaporating section 251, by being cooled and dehumidified, and deprives itself of heat to condense the gas-phase refrigerant C. . As described above, the refrigerant C flows through the refrigerant flow path while undergoing a phase change between a gas phase and a liquid phase, and the treated air A before being cooled by the evaporator 210 and the absolute humidity by being cooled by the evaporator 210 Is exchanged with the treated air A in which the temperature is reduced.

In the case of the cooling operation as the second mode of operation, the solenoid valve 33 is closed to open and the refrigerant C is allowed to flow through the throttle 35, and the solenoid valve 25 is closed and opened to restrict the refrigerant C. A pressure drop is prevented from occurring around 250, and the operation mode is switched from the dehumidification operation as the first operation mode to the cooling operation as the second operation mode. Corresponding to opening the solenoid pulp 243, the operating speed of the compressor 260 is increased to increase the amount of coolant dispensed. The evaporation pressure of the evaporator 210 becomes appropriate, and the refrigerant mass flow rate as the refrigerant flow rate passing through the evaporator also increases.

By doing so, the pressure drop of the refrigerant C around the throttle 250 is reduced to almost zero, and the pressure drop of the refrigerant C excluding the pipe pressure loss occurs at the throttles 330 and 335. The pressure of the refrigerant C in the condensing section 25 2 of the heat exchanger 300 and the evaporating section 25 1 becomes approximately equal to the pressure of the refrigerant C in the evaporator 210, and the evaporator 2 In addition to 10, refrigerant C also evaporates in the condensing section 25 2 and the evaporating section 25 1. Therefore, the heat transfer area of evaporation increases, so that the cooling capacity, that is, the sensible heat treatment capacity can be increased.

In the dehumidifying operation mode, by using the heat exchanger 300 as a reheat heat exchanger for the processing air A before and after passing through the evaporator 210, the amount of water condensed by cooling can be reduced as compared with the cooling operation mode. It is possible to increase the dehumidifying capacity, that is, the latent heat treatment capacity, from the cooling operation mode. As a result, in the dehumidifying operation mode, the humidity can be reduced more quickly than in the cooling operation mode, and it is possible to cope with a so-called low sensible heat ratio and a high humidity indoor air-conditioning load.

Further, in the dehumidifying operation mode, the amount of dew condensation may be increased by reducing the amount of air blown by the blower 102 from that in the cooling operation mode. For this purpose, it is preferable that the blower 102 is also driven by a variable speed motor (not shown) to control the increase and decrease of the rotation speed.

When the dehumidifying air conditioner of the first embodiment is applied to a home air conditioner, the dehumidifying operation can be performed to prevent the room from becoming too cold during the rainy season or sleeping at night in the summer, and provide a comfortable environment with low humidity. Can be made.

As described above, the dehumidifying air conditioner of the present embodiment has a variable sensible heat ratio of the air conditioning load, and can perform energy-saving operation in both the dehumidifying operation and the cooling operation.

In the above description, the cooling speed is controlled by controlling the rotation speed of the compressor driving motor 505. The medium flow rate was adjusted to cope with the cooling load and dehumidification load.At the same time, turning on and off the electric motor and the compressor enabled adjustment beyond the rotational speed control to respond to a wide range of load fluctuations. It may be configured as follows. Next, the operation of the heat pump HP 1 in the dehumidifying operation mode will be described with reference to the Mollier diagram in FIG. For equipment, etc., refer to FIG. 1 as appropriate. FIG. 4 is a Mollier diagram when the refrigerant HF C134a is used. In this diagram, the horizontal axis is enthalpy and the vertical axis is pressure. In addition, examples of the refrigerant C suitable for the heat pump and the dehumidifying air conditioner of the present invention include HF C407C and HFC41OA. These refrigerants C have an operating pressure region shifted to a higher pressure side than HF C134a.

In the figure, point a is the state of the refrigerant outlet of the evaporator 210, and the refrigerant C is in a saturated gas state. The pressure is 0.34MPa, the temperature is 5 ° C, and the enthalpy is 400.9 kj / kg. The state where this gas is sucked and compressed by the compressor 260 and the state at the discharge port of the compressor 260 are indicated by a point b. In this state, the pressure is 0.94 MPa, and the state is a superheated gas.

This refrigerant gas C is cooled in the condenser 220 and reaches a point c on the Mollier diagram. This point is a state of saturated gas, pressure is 0.94MPa, temperature is 38 ° C. Under this pressure, it is further cooled and condensed, reaching point d. This point is a saturated liquid state, the pressure and temperature are the same as point c, and the enthalpy is 250.5 kjZkg.

The refrigerant liquid C is decompressed by the throttle 330 and flows into the evaporating section 251 of the heat exchanger 300. On the Mollier diagram, it is indicated by point e. The pressure is an intermediate pressure of the present invention, and in this embodiment, is a value intermediate between 0.34 MPa and 0.94 MPa. Here, a part of the liquid is evaporated and the liquid and the gas are mixed. In the evaporating section 251, the refrigerant liquid C evaporates under the intermediate pressure and reaches a point f between the saturated liquid line and the saturated gas line at the same pressure. Here, a part of the liquid has evaporated, but the refrigerant liquid C remains to some extent.

The refrigerant C in the state indicated by the point f flows into the condensing section 2 52. In the condensing section 2 52, the refrigerant C is deprived of heat by the low temperature process air A flowing through the second section 320, and reaches point g.

Point g is on the saturated liquid line in the Mollier diagram. The temperature is 18 ° C and the enthalpy is 223.3 kjZkg.

The refrigerant liquid C at the point g is reduced in pressure to 0.34 MPa, which is a saturation pressure at a temperature of 5 ° C., by the throttle 250, and reaches the point. The refrigerant C at this point j reaches the evaporator 210 as a mixture of the refrigerant liquid C and the refrigerant gas C at 5 ° C, where it removes heat from the treated air A, evaporates, and points on the Mollier diagram. It becomes saturated gas in the state of a and is sucked into the compressor 260 again, and the above cycle is repeated.

As described above, in the heat exchanger 300, the refrigerant C changes the state of evaporation from the point e to the point f in the evaporating section 251, and changes from the point ί to the point g1 in the condensing section 2552. The heat transfer coefficient is very high and the heat exchange efficiency is high because of the heat transfer between evaporation and condensation.

Further, as the compression heat pump HP 1 including the compressor 260, the condenser 220, the throttles 330, 250, and the evaporator 210, if the heat exchanger 300 is not provided, the point at the condenser 220 In order to return the refrigerant C in the state of d to the evaporator 210 via the throttle, the enthalpy difference available in the evaporator 210 is 400.9-250.0.5 = 150.04 kj / In the case of the heat pump HP 1 used in the present embodiment with the heat exchanger 300, it is 400.9-223.3 = 177.6 kj the amount of vapor that is circulated to the compressor ² 6 0 to the load, thus the power required Can be reduced by 15%. That is, the same operation as the subcool cycle can be provided.

Next, the operation of the heat pump HP1 in the cooling operation mode will be described. The operation up to point d in the figure is the same as that in the dehumidification operation mode, and the description up to point d is omitted. After leaving the condenser 220, the refrigerant C passes through the throttle 330. After passing through the restrictor, the pressure decreases from 0.94 MPa force to 0.34 MPa, and moves from point d to point j 'in the figure. The enthalpy at this point j 'is 250.5 kJ / kg and the temperature is 5 ° C. The refrigerant evaporates in the heat exchanger 300 and the evaporator 210 to reach the point a.

The dehumidification load and the cooling load will be described with reference to the bar graph in FIG. As shown in the figure, especially in climates such as Japan in temperate and subtropical regions, the maximum value of the dehumidification load (latent heat load) of the air conditioning load is not so different between the midsummer and the rainy season. On the other hand, the sensible heat load increases remarkably in the middle of summer, for example, in August. Therefore, as the design maximum load of the air conditioner that combines cooling and dehumidification, the load at the time of midsummer must be adopted.

On the other hand, the maximum load in the dehumidifying operation mode is less than half of the maximum load in the cooling operation mode. As an example, as shown in the figure, if the total load at midsummer is 100, the latent heat load is 30 and the total load in the rainy season such as the rainy season is 40, and the latent heat load is 2 5

Therefore, the amount of heat to be taken by the evaporator is much higher in the cooling operation mode than in the dehumidification operation mode. This is because the sensible heat load increases as the load increases. However, the latent heat load does not change much between rainy season and midsummer.

According to the embodiment of the present invention, in the cooling operation mode, the heat transfer area that can be used as the evaporator is added to the heat exchanger 300 in addition to the evaporator 210. Therefore, sufficient heat transfer can be secured. In the dehumidifying operation mode, the heat transfer area that can be used as the evaporator corresponds to the evaporator 210, and can be a heat transfer area suitable for the dehumidification load. The heat exchanger 300 can be used for reheating the so-called excessively cooled process air after dehumidification, and at the same time, for pre-cooling the process air.

From another perspective, the heat transfer area of the evaporator, which has a sufficient heat transfer area for the air conditioner dedicated to cooling, is divided into three, and the evaporator 210, evaporator section 251, and condensing section 25 It should be 2. In other words, a compact and efficient air conditioner for both cooling and dehumidification can be constructed by adjusting the refrigerant piping with the same size as the evaporator of the air conditioner dedicated to cooling.

For a climate with a load ratio as shown in the graph of Fig. 5, about 40 to 60% of the heat transfer area of the entire heat exchanger is allocated to the evaporator 210, and the remaining 60 to 40% The heat transfer area may be allocated to the evaporating section 25 1 and the condensing section 25 2 according to the amount of heat transferred.

Also, in the dehumidifying operation mode, the rotation speed of the compressor 260 can be changed to be lower than that in the cooling operation mode, that is, the flow rate of the refrigerant (the amount of rejection) can be reduced. Problems such as frost formation can be prevented even in the heat transfer area. Conversely, if the rotation speed of the compressor 260 cannot be changed, the heat transfer area of the evaporator must be large even in the dehumidifying operation mode (however, the compression load is small because the load is small). According to the embodiment of the present invention, this is not necessary.

Referring to the psychrometric chart in the dehumidifying operation mode of the dehumidifying air conditioner 21 shown in FIG. 6 and the configuration as appropriate with reference to FIG. 1, the dehumidifying operation of the dehumidifying air conditioner 21 equipped with the heat pump HP 1 The operation in the mode will be described. Figure In 6, the alphabetic symbols K, X, L, and M indicate the air condition in each part. This symbol corresponds to the letter circled in the flow diagram in Figure 1. FIG. 6 is applicable to the dehumidifying air conditioner according to another embodiment, which will be described later, as the psychrometric chart.

In the figure, process air A (state K) from the air-conditioned space 101 is sent through the process air path 107 to the first section 310 of the heat exchanger 300, where it is evaporated. Cooled to some extent by refrigerant C evaporating in 25 1. Since this is preparatory cooling before the evaporator 210 cools to the dew point temperature (below), it can be called precooling. During this time, while being pre-cooled in the evaporating section 251, a certain amount of water is removed and the absolute humidity is slightly reduced to reach the point X. Point X is on the saturation line. Alternatively, in the pre-cooling stage, the cooling may be performed to an intermediate point between the point K and the point X. Alternatively, it may be cooled down beyond the point X to a point slightly shifted to a low humidity side on the saturation line.

The pre-cooled process air A is introduced into the evaporator 210 through the passage 108. Here, the processing air A is cooled down to its dew point temperature (below) by the refrigerant C, which is decompressed by the expansion valve 250 and evaporates at a low temperature. Down to point L. The bold line indicating the change from point X to point L is drawn off the saturation line for convenience, but actually overlaps the saturation line.

The treated air A in the state of the point L flows into the second section 320 of the heat exchanger 300 through the path 109. Here, the refrigerant is condensed in the condensing section 252 and is heated to the point M while the absolute humidity is kept constant. At point M, the absolute humidity is sufficiently lower than point K, the dry-bulb temperature is not too low, and the air is sucked in by the blower 102 as air with an appropriate relative humidity and returned to the air-conditioned space 101. Is done.

In the heat exchanger 300, the processing air A is pre-cooled by evaporating the refrigerant C in the evaporating section 251, and the processing air A is reheated by condensing the refrigerant C in the condensing section 250. The refrigerant C evaporated in the evaporating section 25 1 is condensed in the condensing section 25 2. In this way, the heat exchange between the treated air A before and after being cooled by the evaporator 210 is indirectly performed by the same evaporation and condensation of the refrigerant C.

Outside air B is introduced into the condenser 222 through the path 124. This outside air B takes heat from the condensing refrigerant C, and the heated outside air B is sucked into the blower 140 via the route 125 and discharged outside via the route 126 to be discharged as EX. Is done.

Here, in the cycle on the air side shown in the psychrometric chart of Fig. 6, the heat quantity of pre-cooling the processing air A in the first section 310, that is, the processing air A is re-cooled in the second section 320. The amount of heat Δ Δ is the amount of heat recovered, and the amount of heat obtained by cooling the processing air A by the evaporator 210 is AQ. The cooling effect of cooling the air-conditioned space 101 is Δi.

The dehumidifying air conditioner 21 according to the first embodiment has a heat transfer area of the evaporator by using the heat exchanger 300 as an air * air heat exchanger as the evaporator in the cooling operation mode. (5) By elevating the evaporation temperature, the cooling capacity, that is, the sensible heat treatment capacity, can be increased. As a result, the room temperature can be quickly lowered, and it is possible to cope with a so-called high sensible heat ratio, a dry and high-temperature indoor air conditioning load.

That is, in the cooling operation mode, in the psychrometric chart of FIG. 6, the processing air A that has exited the air-conditioning space 101 (FIG. 1) (state K) is the first section 310 of the heat exchanger. (Figure 1), evaporator 210 (Figure 1), second section 3 of heat exchanger The treated air A cooled at 20 (FIG. 1) and exiting the second section 320 of the heat exchanger is in a state represented by a point near point X in the figure. In the cooling operation mode, it is preferable that the air flow rate of the blower 102 is set to be larger than that in the dehumidification operation mode. This is because a large amount of sensible heat can be easily obtained.

The dehumidifying air conditioner 21 of the present embodiment has a heat exchanger in the dehumidifying operation mode.

By using 300 as a reheat heat exchanger for the treated air A before and after passing through the evaporator 210, the amount of water condensed by cooling can be increased from that in the cooling operation mode, and the dehumidification capacity, that is, the latent heat treatment capacity, can be increased. it can. As a result, in the dehumidifying operation mode, the humidity can be rapidly reduced, and it is possible to cope with a so-called low sensible heat ratio and a high humidity indoor air-conditioning load.

The dehumidifying air conditioner 21 has a variable sensible heat ratio of the air conditioning load, and can perform energy-saving operation in both the dehumidifying operation and the cooling operation.

FIG. 7 is a flowchart of a heat pump HP 2 according to a second embodiment of the present invention and a dehumidifying air conditioner 22 that is provided with the heat pump HP 2 and is an example of the dehumidifying air conditioner of the present invention. The difference from the dehumidifying air conditioner of the first embodiment is that the heat exchanger 300 ′ has a first section 310 ′ and a second section 320, which will be described in detail later. It consists of This dehumidifying air conditioner 22 is similar to the dehumidifying air conditioner 21 in that it can perform a dehumidifying operation in which the processing air A is cooled to its dew point temperature (hereinafter, dehumidifying) and a cooling operation. Here, only the heat exchanger 300 'and the evaporator 210 are shown, and the parts common to the first embodiment are omitted.

With reference to FIG. 7, a description will be given focusing on parts different from the first embodiment in the configuration of the heat pump according to the second embodiment and the dehumidifying air conditioner 22 including the same. Evaporation section 2 51 that cools process air A flowing through first section 3 10 ′ of heat exchanger 300 ′, heats process air A flowing through second section 3 20 ′ of heat exchanger 300 ′ After alternately passing through the condensing section 25 2, the evaporating section 25 1 and the condensing section 25 2 (reheating), the path 203, the throttle 250 are arranged in this order, and again the evaporator 2. It returns to 10.

Here, the configuration of the heat exchanger 300 'will be described. The heat exchanger 300 ′ is a heat exchanger that indirectly exchanges heat between the treated air A before and after flowing into the evaporator 210 via the refrigerant C. The heat exchanger 300 ′ is provided with a heat exchange tube (fine) as a refrigerant flow path in each of a plurality of different planes PA, PB, and PC * orthogonal to the plane of the drawing and orthogonal to the flow of the processing air A. Pipes) are arranged substantially in parallel. In this figure, only one tube is shown in each plane for convenience of illustration.

The heat exchanger 300 ′ has a first section 310, through which the processing air A before passing through the evaporator 210 flows, and a second section 310, through which the processing air A flows after passing through the evaporator 210. The second section 3 20 ′ constitutes a separate rectangular parallelepiped space. In both compartments, a partition 301 and a partition 302 are provided adjacent to each other, and a heat exchange tube is provided through the two partitions.

As another form, the heat exchanger 300 divides one rectangular parallelepiped space by one partition wall 301, and a heat exchange tube passes through the partition wall 301 to form a first partition 310 'And the second section 3 20' may be alternately penetrated.

In the figure, the treated air A before being introduced into the evaporator 210 is supplied from the right through the passage 107 to the first section 310, and from the left through the passage 108. get out. It is also cooled to the dew point temperature (below) through the evaporator 210. The treated air A, whose absolute humidity has decreased, is supplied from the left side of the figure through the route 109 to the second section 320, and from the right side through the route 110 is the point of the first implementation. This is the same as the embodiment.

As shown in the figure, the plurality of heat exchange tubes are provided so as to penetrate the first section 310 ′ and the second section 320, and the partition 301 and the partition 302 that partition between the sections. I have. For example, in the heat exchange tube arranged in the plane PA, a portion penetrating the first section 310 ′ is an evaporation section 251A as a first refrigerant flow path (hereinafter, a plurality of evaporation sections are individually separated). When it is not necessary to discuss the above, it is simply referred to as an evaporation section 251, and the portion penetrating the second section 3 20 'is referred to as a condensation section 25 2A (hereinafter a plurality of sections) as a second refrigerant flow path. When the condensing sections do not need to be discussed individually, they are simply referred to as condensing sections. Here, the evaporating section 251 A and the condensing section 25 2 A are a pair of a first section penetrating section and a second section penetrating section, and constitute a refrigerant flow path.

Further, in the heat exchange tube arranged in the plane PB, the evaporating section, which is a portion penetrating the first section 310, is designated as 251B. Further, a portion penetrating the second section 320, which forms a pair of refrigerant flow paths with the evaporating section, is a condensing section 255B as a second refrigerant flow path. And Hereinafter, the refrigerant flow path is configured for the planes P C ··· similarly to the plane P B.

As shown in the figure, the evaporating section 25 1 A and the condensing section 25 52 A form a pair, and are configured as an integrated flow path by one tube. Therefore, in combination with the fact that the first section 3 10 and the second section 3 20 ′ are provided adjacent to each other via the two partition walls 3 0 1 and 3 0 2, the heat exchanger 300, can be formed as a small compact as a whole. In the form of heat exchanger 300 in this figure, the evaporating sections are arranged in the order of 25 1 A, 25 1 B, 25 1 C from the right in the figure, and the condensing section is also on the right in the figure. From 25 2 A, 25 2 B, 25 2 C · '. As further shown, the end of the condensing section 250 A (the end opposite the bulkhead 302) and the end of the condensing section 250B (the end opposite the bulkhead 302) And are connected by a U-tube (YouTube). In addition, the end of the evaporating section 25 1 B and the end of the evaporating section 25 1 C are similarly connected by a U-tube (see Fig. 8B).

Therefore, the refrigerant C flowing in one direction as a whole from the evaporating section 25 A to the condensing section 25 A is guided to the condensing section 25 B by the U-tube, and flows therefrom to the evaporating section 25 B. The U-tube is configured to flow to the evaporating section 25 1 C. In this way, the coolant flow path including the evaporating section and the condensing section alternately repeats and penetrates the first section 310 ′ and the second section 320. Therefore, the heat exchange means 300 is configured such that the evaporation and the condensation performed at the intermediate pressure are performed alternately and repeatedly.

In other words, the refrigerant flow path forms a meandering group of small tubes. The tubules pass through the first section 310 'and the second section 320 while meandering, and alternately contact the processing air A with high temperature and the processing air A with low temperature.

Next, referring to a schematic side view showing the installation state of the dehumidifying air conditioner in FIG. 8 and a perspective view of the heat exchanger, a specific configuration example of the evaporator 210 and the heat exchanger 300 will be specifically described. explain. As shown in Fig. 8B, the evaporating section 251 and the condensing section 252, which are composed of heat transfer tubes (small tubes), are arranged through many plate fins. They are connected to each other by U-tubes outside the outermost fins. The first section 310 and the second section 320 are rectangular parallelepiped spaces formed by arranging a large number of rectangular plate fins in the horizontal direction in the figure. Between the two spaces, there are partitions 301 and 302 (or one partition 301). The condensing section 252, which is a heat transfer tube connected to the evaporating section 251, passes through the first section 310 and the second section 320 while meandering vertically in the figure. ing.

Further, it is preferable that the outer surface of the rectangular parallelepiped space accommodating the plate fin and the thin tube group is surrounded by a plate housing. However, two opposite surfaces of the housing are open, and the processing air passes through the openings. FIG. 8B shows a state in which the plate fin without the housing is exposed.

As described above, the evaporating section 251, which is the refrigerant flow path, and the condensing section 255, respectively, constitute a group of meandering thin tubes. In this way, the refrigerant C flowing in one direction as a whole from the evaporating section 25 1 to the condensing section 25 2 evaporates in the evaporating section 25 1 while flowing in a meandering manner in the small tube group. While condensing in 252, heat from the warmer process air A flowing through the first compartment 310 'is transferred to the cooler process air A flowing through the second compartment 320'.

Similarly, the evaporator 210 also has a structure in which heat transfer tubes pass through a number of rectangular plate fins arranged vertically in the figure. The heat transfer tube penetrates the fins meandering in the horizontal direction in the figure. The evaporator 210 has the same configuration as that of the first embodiment.

Further, the evaporator 210 is disposed between the first partition 310 ′ and the second partition 320 in terms of the flow of the processing air A. In practice, the evaporator 210 is located adjacent to the second compartment 320, 10, is disposed vertically above the second section 320.

As a variant, the evaporator 210 may be arranged adjacent to the first section 310 '.

Next, an example in which the above-described dehumidifying air conditioner is applied as an air conditioner in the air-conditioned space 101 will be described with reference to the schematic cross-sectional view of FIG. 8A. In the air-conditioned space 101, that is, in the indoor unit installed indoors, the first section 310 ', the evaporator 210, and the second section 320' are formed by heat exchange. A blower 102 for circulating the return air RA and the supply air SA is housed. The blower 102 is arranged in a space sandwiched between the first section 310 arranged in an L-shape and the evaporator 210. In this way, the indoor units can be compacted.

The other components such as the outdoor unit are the same as those of the first embodiment, and the description thereof will not be repeated.

Next, the flow of the refrigerant C between the respective devices will be described first with reference to FIG. 7, and subsequently, the operation of the heat pump HP 2 will be described with reference to FIG.

The refrigerant outlet of the condenser 220 (not shown in FIG. 7) is connected to the inlet of the evaporating section 25A of the heat exchanger 300 'via a refrigerant path 202.

The liquid refrigerant C that has exited the condenser 220 is depressurized by a throttle 330 (not shown in FIG. 7), expanded, and a part of the refrigerant C evaporates (flashes). The refrigerant C in which the liquid and gas are mixed reaches the evaporating section 25A, where the liquid refrigerant C flows so as to wet the inner wall of the tube of the evaporating section 25A, and evaporates. Cools (pre-cools) the process air A flowing through the section 310 ′ before flowing into the evaporator 210.

The evaporating section 25 1 A and the condensing section 25 2 A are a series of tubes. It is a loop. That is, since the refrigerant gas C (and the refrigerant liquid C that did not evaporate) flows into the condensing section 25A because it is configured as an integrated flow path, the second section 320 ' Heats (reheats) the treated air A, which has been cooled and dehumidified by the evaporator 210 and has a lower temperature than before flowing into the evaporator 210, and is itself deprived of heat and condensed.

Thus, the heat exchanger 300 ′ connects the evaporating section, which is the refrigerant flow path passing through the first section 310, in the first plane PA, and the second section 320 ′. It has a condensing section (at least a pair, for example, an evaporating section 25 1 A and a condensing section 25 2 A), which is a refrigerant flow path penetrating therethrough, and a second section 3 20 in the second plane PB. The condensing section, which is a refrigerant flow path passing through the first section, and the evaporating section, which is a refrigerant flow path passing through the first section 310 (at least one pair, for example, the condensing section 25 2B and the evaporating section 25) 1 B).

The outlet side of the last condensing section 2 52 2 E of the heat exchanger 300 ′ is connected to the evaporator 210 by a refrigerant liquid pipe 203, and an expansion valve 25 is provided in the refrigerant pipe 203. 0, Solenoid pulp 253 that bypasses the expansion valve 250 is installed.

In the figure, the behavior of the refrigerant C in the evaporating section and the condensing section of the heat exchanger 300 'will be described. First, the refrigerant C in the liquid phase and the gas phase flows into the evaporating section 251A. The refrigerant liquid C may include a small amount of a partially vaporized gas phase. While flowing through the evaporating section 25A, the refrigerant C pre-cools the processing air A and heats itself and flows into the condensing section 25A while increasing the gas phase. The condensing section 25 2 A heats the processing air A, which has a lower temperature than the processing air A in the evaporating section 25 1 A by cooling and dehumidification, and deprives itself of heat and condenses the gas-phase refrigerant C. While letting It enters the next condensing section 25 2 B. While flowing through the condensing section 25 2 B, the refrigerant C is further deprived of heat by the low-temperature process air A, and further condenses the gas-phase refrigerant C. Then, it flows into the next evaporation section 25 1 B. Thus, the refrigerant C flows through the refrigerant channel while changing the phase between the gas phase and the liquid phase. In this way, heat is exchanged between the processing air A before being cooled by the evaporator 210 and the processing air A cooled by the evaporator 210 to reduce the absolute humidity.

In the case of the cooling operation as the second operation mode, the solenoid valve 292 and the solenoid valve 336 (not shown in FIG. 7) are opened to switch from the dehumidification operation as the first operation mode to the second operation mode. The operation mode is switched to the cooling operation as the mode. This is the same as in the first embodiment.

Next, the operation of the heat pump HP 2 in the dehumidifying operation mode will be described with reference to FIG. In addition, refer to Fig. 7 as needed for equipment. FIG. 9 is a Mollier diagram when the refrigerant HFC134a is used.

In the figure, points a, b, c, and d are the same as those in the first embodiment, and a description thereof will be omitted.

The refrigerant liquid C at the point d is decompressed by the throttle 330 and flows into the evaporation section 25A of the heat exchanger 300. On the Mollier diagram, it is indicated by point e. The pressure is an intermediate pressure of the present invention, and in the present embodiment, is a value intermediate between 0.34 MPa and 0.94 MPa. Here, a part of the liquid is evaporated and the liquid and the gas are mixed.

In the evaporating section 25A, the refrigerant liquid C evaporates under the intermediate pressure and reaches a point f1 between the saturated liquid line and the saturated gas line at the same pressure. Here, a part of the liquid has evaporated, but a considerable amount of the refrigerant liquid C remains.

The refrigerant C in the state indicated by the point f1 flows into the condensing section 25A. You. In the condensing section 25 2 A, the refrigerant C is deprived of heat by the cold process air A flowing through the second section 3 20 ′ and reaches the point gl.

The coolant C in the state at the point g 1 flows into the evaporating section ² 5 1 B, where by increasing the heat is removed liquid phase lead to a point f 2, which inflows into the condensing section 2 5 2 B. Here, the liquid phase is increased to reach point g2. Similarly, evaporation and condensation in the evaporating section and the condensing section are repeated. However, in the Mollier diagram shown in the figure, the surface: PC evaporating and condensing sections are omitted, and the condensing section 25 2 B is connected to the expansion valve 2. It is shown as connected to 50.

Point g 2 is on the saturated liquid line in the Mollier diagram. The temperature is 18 ° C and the enthalpy is 23.3 kj / kg.

Refrigerant liquid C at point g 2 is reduced in pressure to 0.34 MPa, which is a saturation pressure at a temperature of 5 ° C., at throttle 250, and reaches point j. The following is the same as in the first embodiment, and a description thereof will not be repeated.

As described above, in the heat exchanger 300 ′, the refrigerant C condenses the change in the state of evaporation from point e to point f 1 or from g 1 to f 2 in the evaporation section 25 1. In Section 2 52, the state of condensation changes from point f1 to point g1 or from point f2 to point g2. Very high efficiency and high heat exchange efficiency.

Furthermore, compared with the case where the heat exchanger 300 ′ is not provided, the first embodiment has the advantage that the amount of gas circulating through the compressor 260 and, consequently, the required power can be significantly reduced for the same cooling load. This is the same as the embodiment.

In the second embodiment, as compared with the first embodiment, the refrigerant can be used repeatedly for the air-air heat exchange in the heat exchanger 300 ′, so that the refrigerant is completely contained in the evaporation section. Without drying out and also condensing section There is an advantage that the refrigerant can be used as a heat transfer medium without being completely condensed inside. However, since the heat transfer tubes must be arranged so that the refrigerant goes back and forth many times between the first section 310 and the second section 320 ′, the first section 310, There are restrictions on the placement of and the second compartment 320. Although the drain pan 450 is shown in FIGS. 1 and 7, this is not limited to the area below the evaporator 210 and also covers the area below the heat exchangers 300 and 300 ′. It is better to provide it as follows. In particular, it is preferable to provide it below the first section 310, 310,. In the first section 310, 310 of the heat exchangers 300, 300, the process air A is mainly precooled, but some moisture may condense here. is there.

In the above embodiment, it has been described that the flow rate (refrigerant mass flow rate) of the refrigerant passing through the evaporator 210 is increased or decreased by increasing or decreasing the rotation speed of the compressor 260. The present invention is not limited to this, and a throttle having a variable opening area may be inserted between the evaporator 210 and the compressor 260 to return the refrigerant gas from the discharge side of the compressor 260 to the suction side. A so-called hot gas bypass may be provided, or a hot gas bypass for introducing the discharge gas of the compressor 260 may be provided between the condenser 220 and the second throttle mechanism 291.

In the first and second embodiments, the return air from the air-conditioned space 101 is introduced into the first sections 310, 310, but the air-conditioned space 10 Outside air may be introduced without introducing return air from 1. It is preferable to pre-cool external air with high humidity and temperature before cooling it with the evaporator 210.This configuration allows air conditioning of hospitals and restaurants that require all external air with a high COP. Can be.

Furthermore, for example, in the Mollier diagram of FIG. 9, the repetition of evaporation and condensation of the refrigerant C occurs as a cycle even if the refrigerant enters the supercooling region beyond the saturated liquid line. Is satisfied, but considering the heat exchange between the processing airs A, it is preferable that the phase change of the refrigerant C is performed in the wet region. Therefore, in the heat exchanger shown in FIG. 9, it is preferable that the heat transfer area of the first evaporator section connected to the throttle 330 (FIG. 1) be larger than the heat transfer area of the subsequent evaporator section. . Also, since the refrigerant C flowing into the throttle 250 (FIGS. 1 and 7) is preferably in a saturated or supercooled region, the heat transfer area of the condensing section connected to the throttle 250 is reduced by It is preferable that the heat transfer area be larger than the heat transfer area of the condensing section.

In the embodiment described above, the evaporator 210 for cooling the processing air A to the dew point (below), and the heat exchangers 300, 300 as pre-coolers for pre-cooling the processing air A Since the same refrigerant is used for the heat transfer medium of the heat exchangers 300 and 300 'as reheaters for performing reheating, the refrigerant system is simplified to a single unit, and the evaporator 21 0, the pressure difference between the condensers 220 can be used, the circulation becomes active, and the boiling phenomenon accompanied by the phase change can be applied to the heat exchange of pre-cooling and re-heating. can do. Although the above embodiment has been described as a dehumidifying air-conditioning apparatus for air-conditioning an air-conditioned space, the dehumidifying air-conditioning apparatus of the present invention is not limited to an air-conditioned space and is applied as a general dehumidifying apparatus to other spaces requiring dehumidification. The dehumidifying air conditioner of the present invention includes such a case.

As described above, according to the present invention, the first controller that increases or decreases the flow rate of the refrigerant passing through the evaporator in accordance with the increase or decrease of the degree of throttle of the first throttle mechanism is provided. Thus, it is possible to provide a heat pump that can adjust the refrigerant flow rate to match the operation mode corresponding to the increase or decrease of the throttle degree. Industrial applicability

INDUSTRIAL APPLICABILITY The present invention can be suitably used for a heat pump which does not cause a problem in the operation of the evaporator even if the degree of throttle of the throttle mechanism is increased or decreased, and a dehumidifying air conditioner which can easily cope with both the cooling operation and the dehumidifying operation.

Claims

The scope of the claims

1. A booster that boosts the refrigerant;

A condenser for condensing the refrigerant and heating a high heat source fluid;

An evaporator for evaporating the refrigerant to cool a low heat source fluid;

Evaporating and condensing the refrigerant at a pressure intermediate between the condensation pressure of the condenser and the evaporation pressure of the evaporator, which is provided in a refrigerant path connecting the condenser and the evaporator, Heat exchange means for cooling the low heat source fluid by evaporation and heating the low heat source fluid by the intermediate pressure condensation;

A first restricting mechanism provided in the refrigerant path between the heat exchange means and the evaporator, the restricting degree being able to be increased and decreased;

A second throttle mechanism provided in the refrigerant path between the condenser and the heat exchange means;

A first controller for increasing or decreasing the flow rate of the refrigerant passing through the evaporator in accordance with an increase or decrease in the degree of throttle of the first throttle mechanism;

The low heat source fluid is configured to receive cooling in the heat exchange means, cooling in the evaporator, and heating in the heat exchange means in this order;

2. The throttle according to claim 1, wherein the throttle of the first throttle mechanism is configured to be reduced to a degree of throttle sufficient to make the intermediate pressure substantially equal to the vaporization pressure of the evaporator. heat pump.

3. The first controller is configured to be able to adjust the refrigerant flow rate at a maximum set flow rate or less, and to control the refrigerant flow rate during the operation in which the first throttle mechanism has the sufficient throttle degree to the first degree. The first throttle mechanism is configured to be adjustable below the maximum set flow rate, and the coolant flow rate during the operation in which the first throttle mechanism is throttled less than the sufficient throttle degree is adjusted to be equal to or less than the second set maximum flow rate; The heat pump according to claim 2, wherein the second set maximum flow rate is configured to be smaller than the first set maximum flow rate.

4. a booster for boosting the refrigerant;

An evaporator for evaporating the refrigerant to cool the processing air to a dew point temperature; and a condensing pressure of the condenser and an evaporating pressure of the evaporator provided in a refrigerant path connecting the condenser and the evaporator. Heat exchange means for evaporating and condensing the refrigerant at a pressure intermediate to the above, cooling the processing air by the intermediate pressure evaporation, and heating the processing air by the intermediate pressure condensation;

The processing air is configured to receive cooling in the heat exchange means, cooling in the evaporator, and heating in the heat exchange means in this order;

Dehumidifying air conditioner.

5. A booster for boosting the refrigerant;

An evaporator for evaporating the refrigerant to cool the processing air to a dew point temperature; and a condensing pressure of the condenser and an evaporating pressure of the evaporator provided in a refrigerant path connecting the condenser and the evaporator. Vaporizes and condenses the refrigerant at a pressure intermediate to the above, cools the processing air by the intermediate pressure evaporation before entering the evaporator, and after the processing air leaves the evaporator by the intermediate pressure condensation Heat exchange means for heating;

A first operation mode in which the processing air is cooled by the heat exchanging means and then heated by the heat exchanging means, and the refrigerant is evaporated by the heat exchanging means at substantially the same pressure as the evaporator. A second operation mode in which the process air is cooled by switching the operation mode;

A first controller for increasing or decreasing the flow rate of the coolant passing through the evaporator in accordance with the switching of the operation mode;