JP7320966B2 - air conditioner - Google Patents

Description

The present invention relates to air conditioners.

In order to increase the comfort of the air-conditioned space and improve productivity, there is a need to set the room temperature to 28 degrees and the relative humidity to 40% in summer. In order to efficiently realize such a temperature and humidity environment, it is useful to use an air conditioner that removes the latent heat of the outside air, reheats it, and performs only sensible heat treatment inside the room.

For example, an air conditioner is known that latently heats air using a desiccant rotor and supplies the air to an air-conditioned space.

JP 2018-54146 A

An air conditioner using a desiccant rotor requires a high heat source for regeneration of the adsorbent. For this reason, the use of the desiccant rotor to perform the sensible heat treatment poses a problem of complicating the piping configuration in the air conditioner.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an air conditioner that reduces the number of heat source water pipes, simplifies the structure of the pipes, and enables highly efficient operation.

In order to solve the above-described problems, an air conditioner according to the present invention is an air conditioner with a dehumidification function that introduces air to remove latent heat and supplies the air to a room to be air-conditioned. a heat pump circuit having a water heat exchanger functioning as a condenser by exchanging heat with a heat pump circuit, and an air heat exchanger functioning as an evaporator by exchanging heat between air and the refrigerant; and a front stage of the air heat exchanger. a precooling air-water heat exchanger that exchanges heat between the heat source water and the air; and a precooling air-water heat exchanger that exchanges heat between the heat source water and the air. a reheating air-water heat exchanger, and a flow path through which the heat source water flows in order of the precooling air-water heat exchanger, the water heat exchanger, and the reheating air-water heat exchanger and a three-way valve for controlling the flow rate of the heat source water flowing from the water heat exchanger to the reheating air-water heat exchanger.

In the air conditioner according to the present invention, heat source water piping can be reduced, the piping configuration can be simplified, and highly efficient operation is possible.

1 is a schematic configuration diagram showing an outside air processor that is an embodiment of an air conditioner according to the present invention; FIG.

An embodiment of an air conditioner according to the present invention will be described with reference to the accompanying drawings. In this embodiment, an example will be described in which the air conditioner according to the present invention is an outside air processor that processes outside air and supplies it to an air-conditioned room.

FIG. 1 is a schematic configuration diagram showing an outside air processor 1, which is an embodiment of an air conditioner according to the present invention.

For example, the outside air processor 1 can remove the latent heat of the outside air 2 to reheat or humidify the outside air 2 while cooling and heating. The outside air 2 processed by the outside air processor 1 is supplied as supply air to an air conditioner (air conditioner in a narrow sense) installed inside the room. By subjecting the outside air 2 mainly to sensible heat treatment by the air conditioner, latent/visual separation air conditioning between the outside air processor 1 and the air conditioner is realized.

The outside air processor 1 includes a heat pump circuit 10, a precooling/preheating air-water heat exchanger 20, a reheating air-water heat exchanger 30, a humidifier 40, a blower 50, and a casing 60. have.

The heat pump circuit 10 includes a heat pump water heat exchanger 11 , a heat pump air heat exchanger 12 , a compressor 13 , an expansion valve 14 and a four-way valve 15 . The heat pump circuits 10 are connected by refrigerant pipes 16 through which refrigerant flows.

The heat pump water heat exchanger 11 (hereinafter simply referred to as "HP water heat exchanger 11") exchanges heat between the heat source water and the refrigerant. The heat pump air heat exchanger 12 (HP air heat exchanger 12) exchanges heat between air and refrigerant. The HP water heat exchanger 11 and the HP air heat exchanger 12 function as evaporators or condensers depending on the operating state of the outside air processor 1 . The compressor 13 compresses the refrigerant flowing through the refrigerant pipe 16 . The compressor 13 is preferably an inverter-controllable compressor with variable capacity. Note that the compressor 13 may be a constant-speed compressor whose capacity is not variable. The expansion valve 14 is provided in the refrigerant pipe 16 between the HP water heat exchanger 11 and the HP air heat exchanger 12, and expands the refrigerant. The four-way valve 15 has four inlets and outlets, and switches the flow path of the refrigerant according to the operating state of the outside air processing machine 1 .

During the cooling process, the refrigerant circulates through the compressor 13, the HP water heat exchanger 11, the expansion valve 14, and the HP air heat exchanger 12 in this order. During the heating process, the refrigerant circulates through the compressor 13, the HP air heat exchanger 12, the expansion valve 14, and the HP water heat exchanger 11 in this order.

The precooling/preheating air-water heat exchanger 20 (hereinafter simply referred to as the "precooling air-water heat exchanger 20" in the explanation of the cooling process) is arranged before the HP air heat exchanger 12, Heat is exchanged between heat source water and air. The reheating air-water heat exchanger 30 is arranged after the HP air heat exchanger 12 and exchanges heat between heat source water and air. A humidifier 40 humidifies the passing air after the precooling air-water heat exchanger 20 . Humidifier 40 is used, for example, for heating in winter. The humidifier 40 is an evaporative humidifier, a steam humidifier, or a natural evaporation humidifier. The evaporative humidifier evaporates the raw water supplied from the raw water pipe 41, mixes the passing air with the vaporized raw water, and humidifies the humidified water. The steam type humidifier vaporizes the raw water supplied from the raw water pipe 41 and mixes and humidifies the passing air and steam. A natural evaporative humidifier retains the supplied raw material water on a cloth or the like, and humidifies the passing air. The blower 50 takes in outside air from the suction port of the casing 60 and blows the air that has passed through the reheating air-water heat exchanger 30 to the air-conditioned room.

Casing 60 houses heat pump circuit 10 , precooling air-water heat exchanger 20 , reheating air-water heat exchanger 30 , humidifier 40 , and blower 50 . The outside air processing machine 1 also has a pipe 70 inside the casing 60 . The pipe 70 forms a flow path through which the heat source water flows through the precooling air-water heat exchanger 20, the HP water heat exchanger 11, and the reheating air-water heat exchanger 30 in this order. The pipe 70 has a two-way valve 71 and a three-way valve 72 . The two-way valve 71 is provided on the piping 70 on the upstream side of the precooling air-water heat exchanger 20, and the flow rate of heat source water supplied from the outside into the casing 60 (precooling air-water heat exchanger 20) to control. The three-way valve 72 is provided on the pipe 70 on the downstream side of the HP water heat exchanger 11 and controls the flow rate of the heat source water flowing through the HP water heat exchanger 11 to the reheating air-water heat exchanger 30 .

Such an outside air processor 1 removes the latent heat of the outside air by switching the flow path of the refrigerant of the heat pump circuit 10 so as to achieve the set dew point temperature and the set supply air temperature based on the indoor temperature and the instruction signal from the outside. , cooling and dehumidification can be performed by supplying air to the air-conditioned room. Details of the cooling process will be described below.

The cooling process uses, for example, medium-temperature cold water of 15 degrees as the heat source water CHS. The medium-temperature cold water has a higher temperature than commonly used cold water (eg, 8 degrees), and is made by a refrigerator so that the temperature is 10 to 22 degrees, preferably 15 to 20 degrees. The outside air processor 1 (control device not shown for the outside air processor 1) controls the four-way valve 15 to switch the heat pump circuit 10 to the cooling process.

For example, the outside air 2 having a temperature of 33° C. and a relative humidity of 60% is heat-exchanged with the heat source water CHS in the pre-cooling air-water heat exchanger 20 to be primarily cooled and dehumidified. The outside air 2 has, for example, a temperature of 18 degrees and a relative humidity of 95%. Next, the outside air 2 is heat-exchanged with the refrigerant in the HP air heat exchanger 12 that functions as an evaporator, and is further cooled and dehumidified to a set dew point temperature (eg, 10 degrees). The dew point temperature of the outside air 2 is controlled by the inverter speed of the compressor 13 . Next, the outside air 2 exchanges heat with the heat source water that has passed through the HP water heat exchanger 11 in the reheating air-water heat exchanger 30, and is reheated to the set supply air temperature (eg, 17 degrees). By the two-way valve 71 so that the heat source water inlet temperature of the reheating air-water heat exchanger 30 is equal to or higher than the set value (for example, "outlet air temperature of the reheating air-water heat exchanger 30" + 3 degrees) Control the heat source water flow rate. The outside air processor 1 controls the reheat amount of the heat source water by controlling the water flow rate to the reheating air-water heat exchanger 30 with the three-way valve 72 . Air that has been cooled, dehumidified, and reheated to the set supply air temperature (for example, a temperature of 24 degrees and a dew point of 10 degrees) is supplied by the blower 50 to each air-conditioned room.

As for the flow of heat source water, heat source water CHS is supplied from the outside of the outside air processing machine 1 and passed through the air-water heat exchanger 20 for precooling. The heat source water CHS exchanges heat with the outside air sucked in by the blower 50 in the precooling air-water heat exchanger 20, and primarily cools and dehumidifies the outside air. The temperature of the heat source water that has passed through the precooling air-water heat exchanger 20 is, for example, 22 degrees.

The heat source water is passed through the HP water heat exchanger 11 that functions as a condenser, and exchanges heat with the refrigerant. The heat source water that has passed through the HP water heat exchanger 11 has a temperature of, for example, 27 degrees. The heat source water is passed through the reheating air-water heat exchanger 30 to exchange heat with the outside air. After passing through the reheating air-water heat exchanger 30, the heat source water CHR has a temperature of, for example, 24 degrees and is returned to the refrigerator or the like.

Such an outside air processor 1 has only two pipes (and one humidifying water supply pipe) for intermediate-temperature cold water as heat source water (and one humidifying water supply pipe). In addition to reducing the number of pipes connected to the main unit, high-efficiency operation is possible.

That is, when the outside air treatment machine 1 is installed, it is only necessary to connect two medium-temperature cold water pipes (and one humidification water supply pipe) to the outside, so labor can be saved during construction. . In addition, the outside air processor 1 can cascade use medium-temperature cold water for primary cooling of outside air, heat source of the heat pump circuit 10, and reheating of excessively cooled outside air. As a result, the outside air processor 1 can recover the amount of heat required when the reheating air-water heat exchanger 30 heats the air in the medium temperature cold water in the outside air processor 1, so that energy loss is small. High efficiency operation is possible. In addition, the outside air processor 1 can increase the temperature difference between medium and cold water, and can reduce the power for transporting the heat source water.

By controlling the four-way valve 15 and switching the heat pump circuit 10 to the heating process, the outside air processor 1 can perform first and second heating processes according to the temperature of the heat source water and the type of humidifier.

The first heating process uses, for example, medium-temperature hot water of 35 degrees as the heat source water CHS. Medium-temperature hot water is lower in temperature than generally used hot water (eg, 50°C), and is produced by a boiler, heat pump, or the like so that the temperature is 15 to 35°C, preferably 35°C. As the humidifier 40, an evaporative humidifier is used.

In the case of medium temperature hot water of 35 degrees, for example, the outside air 2 with a temperature of 0 degrees and a relative humidity of 50% is passed through the precooling/preheating air-water heat exchanger 20 (hereinafter, in the explanation of the heating process, simply referred to as "preheating air-water The water is heat-exchanged with the heat source water CHS in the heat exchanger 20"), and is primarily heated to, for example, 30 degrees. The heated outside air 2 is humidified by the humidifier 40 to a temperature of 14 degrees and a relative humidity of 80%. The outside air 2 then exchanges heat with the refrigerant in the HP air heat exchanger 12, which functions as a condenser, and is further heated to the set supply air temperature (eg, 22°C, 50% relative humidity). The supply air temperature of the outside air 2 is controlled by the inverter rotation speed of the compressor 13 . The air heated to the set supply air temperature is supplied to each room to be air-conditioned by the blower 50 .

Regarding the flow of the heat source water, the heat source water CHS is supplied from the outside of the outside air processor 1 and passed through the preheating air-water heat exchanger 20 . The heat source water CHS exchanges heat with outside air sucked by the blower 50 in the air-water heat exchanger 20 for preheating, and is primarily heated. The temperature of the heat source water that has passed through the preheating air-water heat exchanger 20 is, for example, 29 degrees. The heat source water is passed through the HP water heat exchanger 11 that functions as an evaporator, and exchanges heat with the refrigerant. The heat source water that has passed through the HP water heat exchanger 11 has a temperature of, for example, 27 degrees. The heat source water CHR is returned to the boiler or the like without passing through the reheating air-water heat exchanger 30 under the control of the three-way valve 72 .

The second heating process uses, as the heat source water CHS, medium-temperature hot water (cold water) having a temperature lower than that of the heat source water used in the first heating process, for example, 15°C. A natural evaporation humidifier is used as the humidifier 40 . In this case, the humidifier 40 is installed after the HP air heat exchanger 12 .

For example, the outside air 2 having a temperature of 0 degrees and a relative humidity of 50% exchanges heat with the heat source water CHS in the preheating air-water heat exchanger 20, and is primarily heated to, for example, 12 degrees. The outside air 2 exchanges heat with the refrigerant in the HP air heat exchanger 12 that functions as a condenser, and is heated to a set supply air temperature (for example, 38 degrees). The supply air temperature of the outside air 2 is controlled by the inverter rotation speed of the compressor 13 . The heated outside air 2 is humidified by the humidifier 40 to a relative humidity of 50%. The air heated to the set supply air temperature is supplied to each room to be air-conditioned by the blower 50 .

Regarding the flow of the heat source water, the heat source water CHS is supplied from the outside of the outside air processor 1 and passed through the preheating air-water heat exchanger 20 . The heat source water CHS exchanges heat with outside air sucked by the blower 50 in the air-water heat exchanger 20 for preheating, and is primarily heated. The temperature of the heat source water that has passed through the preheating air-water heat exchanger 20 is, for example, 12.5 degrees. The heat source water is passed through the HP water heat exchanger 11 that functions as an evaporator, and exchanges heat with the refrigerant. The heat source water that has passed through the HP water heat exchanger 11 has a temperature of, for example, 8 degrees. The heat source water CHR is returned to the boiler or the like without passing through the reheating air-water heat exchanger 30 .

Such an outside air treatment machine 1 does not need to prepare a high temperature heat source for adsorbent regeneration as compared with an outside air treatment machine that performs latent heat treatment using a desiccant rotor, so the number of pipes can be reduced, and the system can be simplified.

While several embodiments of the invention have been described, these embodiments have been presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and modifications can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the scope of the invention described in the claims and equivalents thereof.

For example, the pipe 70 has a bypass passage for flowing the heat source water to the reheating air-water heat exchanger 30 without passing through the HP water heat exchanger 11 after the precooling/preheating air-water heat exchanger 20. may Thereby, the outside air processor 1 can control the processing capacity of the heat pump circuit 10 .

Further, the air conditioner according to the present invention is an outdoor air processor for pre-treating air supplied to an air conditioner (air conditioner in a narrow sense) installed in a room to be air-conditioned (indoor), as the outdoor air processor 1 described above. However, it can also be applied to an air conditioner installed in a room to be air-conditioned. Further, it does not matter whether or not the air conditioner installed in the room to be air-conditioned is pretreated by the outside air processor.

Furthermore, the heating process described for the outside air processor 1 is not essential. In this case, humidifier 40 is omitted.

1 Outside air processor 2 Outside air 10 Heat pump circuit 11 Heat pump (HP) water heat exchanger 12 Heat pump (HP) air heat exchanger 13 Compressor 14 Expansion valve 15 Four-way valve 16 Refrigerant piping 20 Air-water heat exchange for precooling and preheating vessel (air-water heat exchanger for precooling)
30 reheating air-water heat exchanger 40 humidifier 41 piping 50 blower 60 casing 70 piping 71 two-way valve 72 three-way valve CHR, CHS heat source water

Claims (5)

An air conditioner with a dehumidifying function that introduces air to remove latent heat and supplies air to a room to be air-conditioned,
a heat pump circuit having a water heat exchanger that exchanges heat between heat source water and a refrigerant and functions as a condenser , and an air heat exchanger that exchanges heat between air and the refrigerant and functions as an evaporator;
an air-water heat exchanger for precooling, which is disposed upstream of the air heat exchanger and exchanges heat between the heat source water and the air;
an air-water heat exchanger for reheating disposed after the air heat exchanger and exchanging heat between the heat source water and the air;
a pipe forming a flow path through which the heat source water flows in order of the precooling air-water heat exchanger, the water heat exchanger, and the reheating air-water heat exchanger;
and a three-way valve for controlling the flow rate of the heat source water flowing from the water heat exchanger to the reheating air-water heat exchanger. 2. The air conditioner according to claim 1, wherein said heat source water is medium temperature cold water of 10 to 22 degrees. 3. The air conditioner according to claim 1, wherein said heat pump circuit has a four-way valve for switching the flow of said refrigerant, and is capable of switching between cooling processing and heating processing. 2. The pipe according to claim 1, wherein the pipe has a bypass passage through which the heat source water flows to the reheating air-water heat exchanger after the precooling air-water heat exchanger without passing through the water heat exchanger. 4. The air conditioner according to any one of 3. a heat pump circuit having a water heat exchanger that exchanges heat between heat source water and a refrigerant, an air heat exchanger that exchanges heat between air and the refrigerant, and a four-way valve that switches a flow path of the refrigerant; ,
an air-water heat exchanger for precooling and preheating, which is disposed upstream of the air heat exchanger and exchanges heat between the heat source water and the air;
an air-water heat exchanger for reheating, which is arranged after the air heat exchanger and exchanges heat between the heat source water and the air;
a pipe forming a flow path through which the heat source water flows in order of the precooling/preheating air-water heat exchanger, the water heat exchanger, and the reheating air-water heat exchanger;
and a three-way valve for controlling the flow rate of the heat source water flowing from the water heat exchanger to the reheating air-water heat exchanger.

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