JP2007163095A - Air conditioning system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air conditioning system capable of efficiently operating by a simple structure. <P>SOLUTION: This air conditioning system comprises a vaporizing auxiliary heat exchanger 10 provided in an indoor unit 3. The heat exchanger 10 is disposed in the front of an evaporator 12 that is an indoor heat exchanger, and adapted to perform heat exchange by the evaporation of dew condensation water by spraying a condensate generated in the evaporator 12 or the like by a spray device 32. A part of low-humidity air supplied from the evaporator 12 to a room is carried to the outer surface of the heat exchanger 10 in addition to the spraying of the condensate. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an air conditioner of a type in which an indoor unit and an outdoor unit are separately installed.

This type of air conditioner is also referred to as a separate air conditioner. In this type of air conditioner, if the outdoor unit is downsized, the capacity (condensing capacity) of the outdoor heat exchanger during cooling operation tends to be insufficient. Has been made. For example, there is a configuration in which condensed water generated in an indoor unit during cooling operation is guided from the indoor unit to the upper part of the outdoor unit using a water distribution pipe and dropped onto the heat exchange part of the outdoor heat exchanger (for example, Patent Literature 1). The condensed water is dropped into the outdoor heat exchanger and evaporated, and the outdoor heat exchanger (in this case, a condenser) is cooled by the latent heat of evaporation. Cooling the outdoor heat exchanger with condensed water makes it easier for the refrigerant to liquefy in the outdoor heat exchanger, thereby improving the condensation capacity.
Utility Model No. 3030042

However, in such an air conditioner, it has been necessary to provide a drain pipe for guiding condensed water from the indoor unit to the outdoor unit. When the outdoor unit is installed at a higher position than the indoor unit, it has been necessary to forcibly convey the condensed water by a pump or the like.
In addition, when condensation water is dripped onto an outdoor heat exchanger that functions as a condenser for cooling, if the humidity of the outdoor atmosphere is very high, the condensation heat will not evaporate and the outdoor heat exchanger will continue. However, sufficient cooling effect could not be obtained.
Furthermore, since the dew condensation water is guided from the indoor unit to the upper part of the outdoor unit and directly dropped onto the outdoor heat exchanger, the dew condensation water that has flowed to the lower part of the heat exchange part cannot be reused.
The present invention has been made in view of such circumstances, and has as its main object to efficiently operate an air conditioner with a simple configuration.

The present invention that solves the above problems evaporates condensed water generated in the indoor unit in an air conditioner in which an indoor unit and an outdoor unit are connected by piping and refrigerant is circulated between the indoor unit and the indoor unit. An evaporative auxiliary heat exchanger that supercools the high-temperature refrigerant flowing into the indoor heat exchanger, and a part of the low-humidity air formed by heat exchange in the indoor heat exchanger, and the evaporative auxiliary heat exchange The air conditioner is characterized in that a duct for supplying air to the chamber is provided in the indoor unit.
In this air conditioner, the refrigerant flowing out of the outdoor unit during the cooling operation is supercooled by the evaporative auxiliary heat exchanger in the indoor unit. The supercooled refrigerant cools the room by exchanging heat with the indoor unit heat exchanger. The air used for supercooling the refrigerant in the evaporative auxiliary heat exchanger takes in a part of the low-humidity air that cools the room and the like.

  According to the present invention, since the evaporative auxiliary heat exchanger is provided in the indoor unit, the refrigerant can be supercooled in the indoor unit using the latent heat of evaporation of condensed water. Since the refrigerant immediately before flowing into the indoor heat exchanger is supercooled using the condensed water generated in the indoor unit, energy efficiency is improved. In addition, it is not necessary to route the drain pipe from the indoor unit to the outdoor unit as in the prior art, and the apparatus configuration can be simplified. Since the low-humidity air that cools the interior of the room is used for heat exchange in the evaporative auxiliary heat exchanger, it is less affected by outside air conditions, and efficient operation can be performed stably.

The best mode for carrying out the invention will be described in detail with reference to the drawings.
FIG. 1 shows an outline of the overall configuration of the air-conditioning apparatus according to the first embodiment. The air conditioner 1 has a configuration in which an outdoor unit 3 and an indoor unit 3 are connected by piping.
The outdoor unit 3 includes a compressor 4, and a discharge pipe 5 connected to a discharge port of the compressor 4 is connected to an inlet of an outdoor heat exchanger (hereinafter referred to as a condenser 6). A liquid pipe 7 extends from the outlet of the condenser 6, and the liquid pipe 7 is drawn into the indoor unit 3.
In the indoor unit 3, an evaporative auxiliary heat exchanger 10 (hereinafter referred to as an auxiliary heat exchanger 10), an expansion valve 11, and an indoor heat exchanger (hereinafter referred to as an evaporator 12) are connected by piping in series. . A gas pipe 13 is connected to the outlet of the evaporator 12. The gas pipe 13 is a suction pipe and is connected to the suction port of the compressor 4 of the outdoor unit 3. In addition, when it sees also as the air conditioning apparatus 1 whole, the condenser 6 and the auxiliary heat exchanger 10 are connected in series.

  As shown in FIG. 2, the indoor unit 3 includes a case 20, and the front surface 20 </ b> A of the case 20 is formed with an air supply port 21 at the upper portion and an air intake port 22 at the lower portion. . In the case 20, a flow path for air passing from the intake port 22 to the air supply port 21 is formed, and an indoor fan 23 is installed in the middle of the air flow path. On the exhaust side (downstream side) of the indoor fan 23, the evaporator 12 is installed obliquely in front of the air supply port 21. That is, when the indoor fan 23 is operated, air is taken in from the air intake port 22, exhausted from the indoor fan 23, exchanges heat through the outer surface of the evaporator 12, and then supplies air into the room from the air supply port 21. Is done. At the lower end of the evaporator 12, a trough 24 is provided for collecting condensed water formed by moisture in the air condensing on the outer surface of the evaporator 12.

  A suction port 25 </ b> A of the duct 25 is disposed in the flow path from the evaporator 12 to the air supply port 21. The duct 25 has a main body portion 25B extending substantially parallel to the bottom portion 20B after descending toward the bottom portion 20B of the case 20 so as to avoid the air inlet 22. In the main body 25B, the auxiliary fan 26 and the auxiliary heat exchanger 10 are arranged in order from the suction port 25A side. Further, the duct 25 from the position where the auxiliary heat exchanger 10 is disposed is a water droplet separating unit 25C. The water droplet separating portion 25C has an increased duct diameter, is bent substantially vertically upward, extends to a position higher than the main body portion 25B, and is then drawn out from the back surface 20C of the case 20 to the outside.

  Here, a drain tank 29 is connected to the bottom of the water droplet separator 25C through an opening 28. A drain pipe 30 extending from the tub 24 of the evaporator 12 installed above is drawn into the drain tank 29. The condensed water stored in the drain tank 29 is pumped out by a pump 31 and supplied to a watering device 32 provided at the upper part of the auxiliary heat exchanger 10. The water sprinkler 32 has, for example, a configuration in which a plurality of small holes are drilled toward the auxiliary heat exchanger 10 in a pipe that passes condensed water, or a nozzle in which a large number of minute holes are formed toward the auxiliary heat exchanger 10. Etc., and is configured so that condensed water can be sprayed substantially uniformly on the outer surface of the auxiliary heat exchanger 10.

Next, the operation of this embodiment will be described.
When operating the air conditioner 1 shown in FIG. 1, the compressor 4 compresses and discharges the gas refrigerant. The high-pressure gas refrigerant is a two-phase refrigerant in which the liquid refrigerant or a part of the gas refrigerant remains after heat exchange in the condenser 6. The liquid refrigerant or the two-phase refrigerant flows into the auxiliary heat exchanger 10 of the indoor unit 3. Since the dew condensation water is sprinkled from the watering device 32 in the auxiliary heat exchanger 10, the dew condensation water adhering to the outer surface of the auxiliary heat exchanger 10 flows through the auxiliary heat exchanger 10. Heat and vaporize by exchanging heat with liquid refrigerant or two-phase refrigerant. At this time, the auxiliary heat exchanger 10 and the refrigerant are cooled by the vaporization heat absorbed by the condensed water. The liquid refrigerant or the two-phase refrigerant becomes a supercooled liquid refrigerant by heat exchange, is decompressed by the expansion valve 11, and then flows into the evaporator 12.

  In the evaporator 12, the heat of the air flowing outside the evaporator 12 is removed by heat exchange and evaporated to become a low-pressure gas refrigerant. The low-pressure gas refrigerant is returned to the outdoor unit 3, sucked into the compressor 4, compressed again and discharged. The air cooled by heat exchange in the evaporator 12 shown in FIG. 2 is blown out from the intake port 22 as air for cooling the room (indoor blowing air). In addition, when air for indoor blowing is formed, the water | moisture content in air condenses on the surface of the evaporator 12, and forms dew condensation water. For this reason, the indoor blowing air becomes low-humidity air.

  Condensed water flows down along the outer surface of the evaporator 12 to the trough 24 and is collected from the drain pipe 30 to the drain tank 29. In addition, as the auxiliary fan 26 in the duct 25 rotates, a part of the indoor blowing air is sucked from the suction port 25A.

  The indoor blowing air sucked into the duct 25 is guided from the auxiliary fan 26 through the auxiliary heat exchanger 10 to the water droplet separator 25C. At this time, the vapor of the dew condensation water sprayed on the auxiliary heat exchanger 10 and evaporated on the outer surface of the auxiliary heat exchanger 10 is mixed with the indoor blowing air to become humidified air. When the humidified air flows from the auxiliary heat exchanger 10 into the water droplet separator 25C having a large cross-sectional area, the flow velocity decreases. As a result, excess water such as large water droplets is dropped and collected in the drain tank 29 from the opening 28. Furthermore, since the direction of the humidified air flow is changed following the bent shape of the water droplet separating unit 25C, excessive water such as a large water droplet collides with the inner wall of the water droplet separating unit 25C or condenses. Water droplets left on the inner wall of the water droplet separator 25C are collected in the drain tank 29 through the duct 25. The humidified air exhausted from the duct 25 is exhausted outdoors.

  Here, generally, the capacity Q of the evaporative heat exchanger is proportional to the amount of water evaporation E per unit time. Therefore, in order to use the auxiliary heat exchanger 10 using condensed water most efficiently, it is preferable to evaporate the condensed water without using it and use the latent heat of evaporation for cooling the condenser 6. The evaporation amount E of water per unit time in the air can be expressed as E = k × F × (hw−h). However, k is an evaporation coefficient and F is an evaporation area. hw indicates the water vapor pressure at the evaporation temperature tw, and h is the water vapor partial pressure.

  Since the evaporation coefficient k is a coefficient determined by pressure, it is necessary to increase (hw−h) in order to increase the evaporation amount E in a heat exchanger having a constant evaporation area F. Since hw is the water vapor pressure at the evaporation temperature tw, considering that it is determined by the condensation temperature t, in order to increase the evaporation amount E, the water vapor partial pressure h of the air to be evaporated may be reduced. The water vapor partial pressure h of air is determined by the absolute humidity x of air, and decreases as the absolute humidity x decreases.

  Therefore, the amount of evaporation on the outer surface of the auxiliary heat exchanger 10 can be increased by using dehumidified air having a small absolute humidity x like the indoor blowing air of the present embodiment. For example, when the evaporation temperature tw is 38 ° C., the outdoor air temperature conditions (dry bulb temperature 35 ° C./wet bulb temperature 24 ° C.) and indoor blowing air (dry bulb temperature 11 ° C./wet bulb temperature) under the JIS cooling standard conditions. When the evaporation amount E at 10 ° C. is compared, the evaporation amount is about 1.25 times when the indoor blowing stem is used.

According to this embodiment, since the auxiliary heat exchanger 10 is provided in front of the condenser 6 in the indoor unit 3, efficient auxiliary heat exchange using the latent heat of vaporization in the indoor unit 3 becomes possible, and energy The utilization efficiency can be improved. Further, it is not necessary to route a drain pipe from the indoor unit 3 to the outdoor unit 3 in addition to the liquid pipe and the gas pipe as in the prior art. As a result, the apparatus configuration is simplified and the layout can be easily changed. The installation work of the air conditioning apparatus 1 becomes easy.
Further, a part of the air for indoor blowing is drawn into the duct 25 using the auxiliary fan 26 and used for auxiliary heat exchange. Since the indoor blowing air is air having a constant temperature and humidity, the condensed water can be evaporated by the auxiliary heat exchanger 10 without being affected by the outside air conditions, and a stable operation can be realized. A part of the air for indoor blowing is not used for air conditioning in the room, but is used for evaporation of condensed water or exhaust of humidified air. As a result, the power is not wasted.
Since the water droplet separator 25C is provided in the duct 25, the air exhausted from the duct 25 is prevented from being excessively humidified. For this reason, it becomes possible to utilize the dew condensation water of the drain tank 29 effectively, and it becomes possible to scatter dew condensation water to the auxiliary heat exchanger 10 stably. Further, by exhausting the air in a moderately humidified state, a drain hose exposed to the outside is not required to discharge the condensed water as it is.

  It should be noted that this embodiment can be applied to a multistage expansion refrigeration cycle. As an example, FIG. 3 shows a case of a two-stage compression two-stage expansion refrigeration cycle. The indoor unit 3 of the air conditioner 41 has the same configuration as that in FIG. In the outdoor unit 42, the discharge pipe 5 from the first stage compressor 4 is connected to the intermediate cooler 43. For example, a gas-liquid separator is used for the intercooler 43. A suction pipe 44 extends from the intercooler 43 toward the suction port of the second-stage compressor 45. The suction pipe 44 is a pipe through which an intermediate-pressure gas refrigerant flowing out from the intermediate cooler 43 flows. The discharge pipe 46 of the second-stage compressor 45 is a pipe through which high-pressure gas refrigerant flows, and is connected to the inlet of the condenser 6. A pipe 47 is connected to the outlet of the condenser 6, and the pipe 47 is connected to the intercooler 43 after a supplementary expansion valve 48 is provided on the way. Furthermore, the intermediate cooler 43 is connected to a liquid pipe 7 through which an intermediate-pressure liquid refrigerant flows out. The liquid pipe 7 is drawn into the indoor unit 3.

  In this configuration, the intermediate pressure refrigerant flows into the auxiliary heat exchanger 10. The intermediate pressure is a pressure equal to or higher than the discharge pressure of the first stage compressor 4 and lower than the discharge pressure of the second stage compressor 45. Since the medium-pressure refrigerant has a small difference from room temperature, the conventional configuration cannot sufficiently dissipate heat to the air. However, by using the auxiliary heat exchanger 10 provided in the indoor unit 3, the latent heat of evaporation of condensed water It becomes possible to stably carry out the supercooling of the refrigerant using. Other effects are the same as described above.

A second embodiment of the present invention will be described in detail with reference to the drawings. In addition, the same code | symbol is attached | subjected to the same component as 1st Embodiment. In addition, overlapping explanation is omitted.
As shown in FIG. 4, the indoor unit 3 has a duct 51 in the case 20. The duct 51 has an intake port 51A for sucking a part of indoor blowing air. The main body 51B has an auxiliary fan 26, a venturi unit 52, and the auxiliary heat exchanger 10 in order along the air flow direction. Is arranged. From the portion where the auxiliary heat exchanger 10 is disposed, after the drain tank 29 is connected through the opening 28, the air is exhausted from the back surface 20C of the case 20 to the outside.

  The venturi 52 has a shape in which the cross-sectional area of the duct 51 is reduced toward the auxiliary heat exchanger 10 after the cross-sectional area of the duct 51 is reduced by the curved surface shape, and the cross-sectional area is the narrowest. Nozzle 53 is provided. The nozzle 53 has an opening on one end side disposed in the duct 51, and an opening on the other end side is inserted into the condensed water stored in the drain tank 29.

The operation of this embodiment will be described.
When the auxiliary fan 26 is operated, a part of the indoor blowing air is sucked into the duct 51 from the intake port 51A. The indoor blowing air is squeezed by the venturi 52 and the flow velocity increases. As a result, the pressure in the venturi portion 52 becomes relatively low compared to other portions. For this reason, the dew condensation water in the drain tank 29 is sucked through the nozzle 53. The condensed water is ejected from the nozzle 53 into the duct 51 and becomes a mist and mixed with the indoor blowing air. When air containing mist of condensed water is introduced to the auxiliary heat exchanger 10, mist of condensed water adheres to the outer surface of the auxiliary heat exchanger 10. As the mist of condensed water evaporates, the auxiliary heat exchanger 10 performs heat exchange using latent heat of vaporization. The refrigerant flowing in the auxiliary heat exchanger 10 is led to the condenser 6 after being supercooled by evaporation of condensed water. On the other hand, the air flowing on the outer surface of the auxiliary heat exchanger 10 is discharged to the outdoors as humidified air containing vapor of condensed water. At this time, excess water is collected in the drain tank 29.

According to this embodiment, the venturi portion 52 is provided in the duct 51 and the condensed water is sprayed on the outer surface of the auxiliary heat exchanger 10 using the pressure difference caused by the change in the wind speed. No power is needed to spray water. In addition, the apparatus configuration is simplified. The effect of providing the auxiliary heat exchanger 10 in the indoor unit 3 and the effect of using the indoor blowing air are the same as in the first embodiment.
Here, as shown in FIG. 5, the duct 51 may be provided with a water droplet separator 51 </ b> C on the downstream side of the installation position of the auxiliary heat exchanger 10. The configuration of the water droplet separation unit 51C may be the same as that of the water droplet separation unit 25C of the first embodiment. By providing the water droplet separation unit 51C, it is possible to effectively use the condensed water as in the first embodiment.

A third embodiment of the present invention will be described in detail with reference to the drawings. In addition, the same code | symbol is attached | subjected to the same component as each said embodiment. In addition, overlapping explanation is omitted.
As shown in FIG. 6, the indoor unit 63 includes a duct 25 that is only partially illustrated, and a drain tank 29 connected to the downstream side of the duct, and the auxiliary heat exchanger 10 is provided in the duct 25. Is arranged. Although not shown, an auxiliary fan 26 and a suction port 25A are provided on the upstream side of the duct 25 as in FIG. 2, and the back surface of the case 20 is connected to the downstream side of the duct 25 via a water droplet separating unit 25C. The gas is exhausted from 20C.

  Here, the liquid pipe 7 extending from the outdoor unit 3 to the indoor unit 3 is inserted into the drain tank 29, and after being routed while being bent many times along the bottom of the drain tank 29, the auxiliary heat exchanger 10. Connected to the inlet.

The operation of this embodiment will be described.
The two-phase refrigerant formed by the condenser 6 of the outdoor unit 3 in which the liquid refrigerant or part of the gas refrigerant remains is led to the indoor unit 63 and passes through the portion inserted into the drain tank 29 to the auxiliary heat exchanger 10. Inflow. At this time, the dew condensation water in the drain tank 29 is, for example, about 15 ° C. and the temperature difference from the refrigerant is about 30 ° C., so that the refrigerant flowing through the liquid pipe 7 exchanges heat with the dew condensation water in the drain tank 29. Increase the temperature of the condensed water. Condensed water whose temperature has been increased by heat exchange is sprayed on the outer surface of the auxiliary heat exchanger 10 via the sprinkler 32 and supercools the refrigerant by latent heat of vaporization.

  When stopping the cooling operation, the indoor fan 23 (see FIG. 2) is stopped first, and the compressor 4 and the auxiliary fan 26 are stopped after a predetermined delay. Until the auxiliary fan 26 and the like are stopped, low-humidity air is supplied into the duct 25 and heat dissipation in the drain tank 29 is continued. As a result, the inside of the drain tank 29 and the outer surface of the auxiliary heat exchanger 10 can be dried.

  According to this embodiment, the liquid pipe 7 and the dew condensation water in the drain tank 29 are heat-exchanged and heated before the dew condensation water is sprayed. In addition, the condensed water tends to evaporate. As a result, the amount of evaporation increases and it becomes easy to take latent heat, and the refrigerant can be efficiently supercooled. If only the indoor fan 23 is stopped first when the cooling operation is stopped, the inside of the drain tank 29 and the outer surface of the auxiliary heat exchanger 10 can be dried, so that propagation of germs and molds can be prevented. Other effects are the same as those of the first embodiment. Here, if the venturi part 52 shown in FIG. 4 is provided instead of the watering device 32, the same effect as the second embodiment can be obtained.

The present invention can be widely applied without being limited to the above-described embodiments.
For example, the air conditioner 1 may be configured to be capable of heating operation by providing a four-way valve or the like to reverse the direction of the refrigerant.
In the first embodiment, when an auxiliary fan 26 that can be rotated forward and backward is used, it is possible to exhaust air during forward rotation and intake air during reverse rotation. By being able to inhale, the air conditioning apparatus 1 is provided with a ventilation function. That is, humidified air containing the condensed water vapor that is taken in from the sprinkler 32 by taking in the outside air is supplied from the suction port 25A of the duct 25 and supplied to the room through the air supply port 21 so that the outside air can be ventilated. Become.

It is a figure which shows schematic structure of the air conditioning apparatus which concerns on embodiment of this invention. It is sectional drawing which shows the specific structure of an indoor unit. It is a figure showing a schematic structure in case an air harmony device is a two-stage compression two-stage expansion refrigerating cycle. It is sectional drawing which shows the structure which provided the venturi part in the duct of the indoor unit. It is sectional drawing which shows the structure which provided the venturi part and the water droplet isolation | separation part in the duct of the indoor unit. It is sectional drawing which shows the structure which draws a part of liquid pipe in a drain tank in room air.

Explanation of symbols

1,41 Air conditioner 2 Outdoor unit 3 Indoor unit 6 Condenser (Outdoor heat exchanger)
7 Liquid tube 10 Auxiliary heat exchanger (evaporation type auxiliary heat exchanger)
12 Evaporator (indoor heat exchanger)
25, 51 Duct 25C, 51C Water drop separator (bent part)
29 Drain tank 32 Watering device 43 Intermediate cooler 52 Venturi section 53 Nozzle

Claims (7)

  In an air conditioner in which an indoor unit and an outdoor unit are connected by piping and a refrigerant is circulated between the indoor unit and the indoor unit, the condensed water generated in the indoor unit is evaporated to flow into the indoor heat exchanger. An evaporative auxiliary heat exchanger that supercools the high-temperature refrigerant, and a duct that takes in a portion of the low-humidity air formed by heat exchange in the indoor heat exchanger and sends it to the evaporative auxiliary heat exchanger. An air conditioner provided in the indoor unit.   The air conditioning apparatus according to claim 1, wherein the evaporative auxiliary heat exchanger is connected in series with an outdoor heat exchanger.   The air conditioning apparatus according to claim 1, wherein the evaporative auxiliary heat exchanger is provided between an intermediate cooler and an expansion valve in a two-stage compression and two-stage expansion refrigeration cycle.   The evaporative auxiliary heat exchanger is disposed in the duct into which a part of the low-humidity air is drawn, and includes a watering device that sprays the condensed water generated in the indoor unit to the evaporative auxiliary heat exchanger. The air conditioning apparatus according to any one of claims 1 to 3, wherein   The evaporative auxiliary heat exchanger is disposed in the duct into which a part of the low-humidity air is drawn, and the duct has a venturi portion upstream of the position where the evaporative auxiliary heat exchanger is disposed. The nozzle according to any one of claims 1 to 3, wherein a nozzle connected to a drain tank in which condensed water generated in the indoor unit is stored is provided in the venturi section. Air conditioner.   6. The air conditioner according to claim 4, wherein the duct has a portion that increases a cross-sectional area and bends downstream of the evaporative auxiliary heat exchanger. A part of a liquid pipe extending from the outdoor unit and connected to the evaporative auxiliary heat exchanger is drawn into a drain tank in which condensed water generated in the indoor unit is stored, and heat exchange between the condensed water and the refrigerant is performed. The air conditioner according to claim 1, wherein the air conditioner is arranged in a possible manner.

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