JP2001201208A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioner in which the dry operation of appropriate mode can be automatically selected and executed, depending on the season, while enhancing the operability of dry operation. SOLUTION: The air conditioner comprises an outdoor unit 10, comprising an outdoor heat exchanger 11 and a compressor 12, and an indoor unit 20 comprising an indoor heat exchanger 21, a reheating/drying indoor heat exchanger 22 and a drying solenoid valve 23 provided between the indoor heat exchanger 21, 22 where the indoor heat exchanger 21 dehumidifies indoor air, by throttling the drying solenoid valve 23 to discharge heat to refrigerant, and the reheating/ drying indoor heat exchanger 22 can perform reheating/drying operation for heating the dehumidified air with waste heat of refrigerant before supplying it into a room. In such an air conditioner, operating state of the compressor 12 is varied so that the indoor humidity approaches a target level of selected mode, at reheating/drying operation by detecting current indoor temperature TIon and outdoor temperature TO and selecting an appropriate operation mode based on the detection results.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reheat dry type air conditioner capable of controlling the temperature of conditioned air supplied from an indoor unit even when a dry operation is selected.

[0002]

2. Description of the Related Art In a conventional air conditioner, when a dry operation is selected, a refrigeration cycle is performed so that the indoor humidity approaches a preset target humidity based on a detection result of a humidity sensor. Control.

[0003] In the above-mentioned dry operation, since the cooling operation is actually performed, it is undeniable that the temperature in the room is lower than when the dry operation is started. In order to solve this problem, it is necessary to adjust the temperature of the conditioned air supplied from the indoor unit during the refrigeration cycle in the upward direction, but this is not possible with a conventional air conditioner due to its structure.

[0004] In recent years, reheat dry type air conditioners have been developed which enable temperature control of conditioned air even when dry operation is selected. This is for the indoor unit,
A heat exchanger for reheating and drying is provided separately from the conventional indoor heat exchanger.When normal cooling or heating operation is selected, the same operation as the indoor heat exchanger is performed for the heat exchanger for reheating and drying. When the dry operation is selected, the heat exchanger for reheating and drying is operated in the same manner as the outdoor heat exchanger (that is, exhaust heat).
And heats the conditioned air dehumidified (cooled) by the indoor heat exchanger, and finally controls the temperature of the conditioned air supplied from the indoor unit to approach the original indoor temperature. I have.

[0005] According to the reheat dry type air conditioner, the above-mentioned problems are solved, and even when the dry operation is selected, the temperature and humidity in the room can be appropriately maintained.

[0006] Not only the reheat-dry type air conditioner having the excellent functions as described above, but also the conventional air conditioners, the dry operation includes "condensation prevention mode", "mold / mite prevention mode", " There are three types of driving modes of "comfort mode".

[0007] The dew condensation prevention mode is selected in winter to achieve moderate humidity to prevent indoor dehydration while preventing the occurrence of dew condensation, and the mold / tick prevention mode is selected in the middle of spring and fall to generate mold and mite. The comfortable mode is selected in the summer to achieve a comfortable indoor temperature and humidity that provides a cool feeling.

[0008]

In the meantime, these operation modes are designed so that the user can select an appropriate one according to the time of day and execute it. It is necessary to perform an operation of selecting and executing one of the two modes, and it is pointed out that the operability is inferior.

The present invention has been made in view of the above circumstances, and an air conditioner capable of automatically selecting and executing an appropriate mode of dry operation according to time while improving operability during dry operation. It is intended to provide.

[0010]

As means for solving the above-mentioned problems, an air conditioner having the following configuration is employed. That is, the air conditioner according to claim 1 performs an heat exchange between the outdoor heat exchanger that performs heat exchange between the outdoor air and the refrigerant, and heat exchange between the outdoor heat exchanger or the indoor air and the refrigerant. An outdoor unit including a compressor that sends a refrigerant to a first indoor heat exchanger, and an outdoor fan that allows outdoor air to flow through the outdoor heat exchanger; and the first indoor heat exchanger;
A second indoor heat exchanger that performs heat exchange between indoor air and a refrigerant similarly to the first indoor heat exchanger, and the first and second indoor heat exchangers;
A solenoid valve provided between the indoor heat exchangers of the first, the first,
An indoor unit having an indoor fan that allows indoor air to flow through the second indoor heat exchanger. The indoor unit is squeezed to function as an expansion valve. The second indoor heat exchanger absorbs heat to dehumidify the indoor air, and in the second indoor heat exchanger, heats the air after the dehumidification by heating the air after the dehumidification and supplies the air indoors. In the reheating dry operation, the current indoor temperature and the outdoor temperature are detected, and an appropriate mode is selected from a plurality of operation modes of the reheat dry operation set in advance based on the detection result, The operation state of the compressor is changed so that the indoor humidity approaches the target humidity in the selected mode.

The air conditioner according to a second aspect of the present invention is the air conditioner according to the first aspect, wherein the operating state of the outdoor fan and the indoor fan is also changed with a change in the operating state of the compressor. I do.

According to a third aspect of the present invention, there is provided the air conditioner according to the first or second aspect, wherein when the reheat dry operation is instructed, if the indoor humidity is higher than a predetermined value, the reheat is performed. The cooling operation is performed temporarily before the start of the dry operation.

According to a fourth aspect of the present invention, in the air conditioner of the first, second or third aspect, a plurality of blinking display units are provided on the indoor unit, and the selected reheating dry operation is performed. The mode is represented by the explicit number of the display unit.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an air conditioner according to the present invention will be described with reference to FIGS. FIG. 1 shows a system configuration of the air-conditioning apparatus according to the present embodiment. This air conditioner includes an outdoor unit 10 and an indoor unit 20. The outdoor unit 10 and the indoor unit 20 are connected to a refrigerant pipe 30 through which the refrigerant flows.
And electrical wiring (not shown).

The outdoor unit 10 includes an outdoor heat exchanger 11 for exchanging heat between outdoor air and a refrigerant, and a compressor 12 for sending the refrigerant to the outdoor heat exchanger 11 or an indoor heat exchanger 21 described later. A four-way valve 13 that regulates the flow direction of the refrigerant flowing through the refrigerant pipe 30, an electromagnetic expansion valve 14 that expands a high-temperature and high-pressure liquid refrigerant during cooling operation to produce a low-temperature and low-pressure liquid refrigerant, and an outdoor heat exchanger. 11 is provided with a propeller fan (indoor fan) 15 for circulating outdoor air.

The indoor unit 20 includes an indoor heat exchanger (first indoor heat exchanger) 21 for exchanging heat between indoor air and a refrigerant, and an indoor heat exchanger 21 between the indoor air and the refrigerant. A reheat drying indoor heat exchanger (second indoor heat exchanger) 22 for performing heat exchange and a refrigerant pipe 30 between the indoor heat exchanger 21 and the reheat drying indoor heat exchanger 22 are provided. A dry solenoid valve 23 that functions as an expansion valve during dry operation;
Indoor heat exchanger 21 and indoor heat exchanger 22 for reheat drying
And a tangential fan (indoor fan) 24 for circulating indoor air.

Further, the outdoor unit 10 is provided with an outside air temperature sensor 16 for detecting outdoor temperature, and the indoor unit 20 is provided with a room temperature sensor 25 for detecting indoor temperature and a humidity sensor 26 for detecting indoor humidity. ing. These sensors are connected to a control unit (not shown). In the control unit, based on the detection results of the outside air temperature sensor 16, the room temperature sensor 25, and the humidity sensor 26, the operation state of the compressor, the opening degrees of the electromagnetic expansion valve 14 and the dry electromagnetic valve 23, the propeller fan 15 and the tangential fan 24
The control is performed such as intermittently or stepwise changing the operating state of the vehicle.

Next, a description will be given of how the air conditioner constructed as described above operates during the heating operation and the cooling operation. During the heating operation, the refrigerant flowing through the refrigerant pipe system is compressed by the compressor 12 to become a high-temperature and high-pressure gas refrigerant, sent to the indoor unit 20 through the refrigerant pipe 30, and
It flows in the order of the indoor heat exchanger 21 and the indoor heat exchanger 22 for reheat drying. In the indoor unit 20, heat is given to the indoor air taken in by the tangential fan 24 from the high-temperature and high-pressure gas refrigerant passing through the indoor heat exchanger 21 and the indoor heat exchanger 22 for reheating and drying. Hot air will be supplied.

The high-temperature and high-pressure gas refrigerant exhausted to the indoor air is condensed and liquefied in the indoor heat exchanger 21 and the reheat-drying indoor heat exchanger 22 to become a high-temperature and high-pressure liquid refrigerant.
The high-temperature and high-pressure liquid refrigerant is sent to the outdoor heat exchanger 11 in the outdoor unit 10 through the refrigerant pipe 30. In the outdoor unit 10, the high-temperature and high-pressure liquid refrigerant passing through the outdoor heat exchanger 11 takes heat from the outdoor air taken in by the propeller fan 15. As a result, the high-temperature and high-pressure liquid refrigerant evaporates and becomes a low-temperature and low-pressure gas refrigerant.
This is sent again to the compressor 12, and the above process is repeated.

Next, during the cooling operation, the refrigerant flows through the refrigerant piping system in a direction opposite to the above. First, the high-temperature and high-pressure gas refrigerant compressed by the compressor 12 passes through the refrigerant pipe 30 and is sent to the outdoor heat exchanger 11, and gives heat to outdoor air to be condensed and liquefied to become a high-temperature and high-pressure liquid refrigerant. . The high-temperature and high-pressure liquid refrigerant becomes a low-temperature and low-pressure liquid refrigerant in the process of passing through the electromagnetic expansion valve 14 whose opening is narrowed, and is sent to the indoor unit 20 through the refrigerant pipe 30 to be used for indoor heat exchange for reheating and drying. Vessel 22,
It circulates in the order of the indoor heat exchanger 21. In the indoor unit 20, the low-temperature and low-pressure liquid refrigerant takes heat from the indoor air to cool, and the refrigerant itself evaporates and becomes a low-temperature and low-pressure gas refrigerant. This is sent to the compressor 24 again, and the above process is repeated.

Next, a description will be given of an operation method when the reheat dry operation is selected in the air conditioner configured as described above. The flow of the refrigerant during the reheating dry operation is the same as that during the cooling operation, but the electromagnetic expansion valve 14 remains open, the opening of the dry electromagnetic valve 23 is reduced, and a function as an expansion valve is provided. Thereby, in the indoor unit 20, after the indoor air is dehumidified (cooled) by the indoor heat exchanger 21, the dehumidified air is heated by the reheat drying indoor heat exchanger 22 and then supplied to the room. .

When the reheat dry operation is selected, the following control is performed. The control flow will be described with reference to the flowcharts shown in FIGS. In the flow charts of FIGS. 2 and 3, TIon is the indoor temperature, HS is the indoor humidity, and the outdoor temperature is TIon.
Notated as TO.

First, in step S1, a region determination is performed for the current indoor temperature (TIon) and outdoor temperature (TO). As for the room temperature, as shown in FIG.
It is determined whether the temperature is below (region (I)) or 25 ° C. or higher (region (II)). The outdoor temperature is 10 ° C. or less (region (a)) as shown in FIG.
It is determined whether the temperature is lower than or equal to 0 ° C. (area (b)) or higher than 25 ° C. (area (c)).

Further, in step S1, FIG.
Based on the determination result of (b), the operating condition of the air conditioner is 3
Is switched to one pattern. How to switch the operation state is determined according to the chart of FIG. When the indoor temperature is in the area (I) and the outdoor temperature is in the area (A), when the indoor temperature is in the area (II) and the outdoor temperature is in the area (A), in these cases, dew condensation prevention in winter The mode is considered selected.

In the dew condensation prevention mode, first, in step S
In step 2, it is determined whether or not the air conditioner is in a state immediately after the start. If the air conditioner is just after the start, the heating operation (step S3) and the defrost operation (step S4) are sequentially performed for a predetermined time as a low outside temperature start operation. Go to step S
At 5, the reheat dry (standard) operation (pattern A shown in FIG. 6) is started. If it is not immediately after the start, the reheat dry (standard) operation is started immediately without performing the low outside temperature start operation. In the reheat dry (standard) operation, the compressor 12 is operated to exhibit a medium capacity and the propeller fan 15 is operated.
Is rotated at a low speed, and the tangential fan 24 is rotated at a medium speed.

After the start of the reheat dry (standard) operation, it is determined in step S6 whether or not one hour has elapsed since the start of this control (at the time of start). If one hour has elapsed, the flow returns to step S1. The area determination for the current indoor temperature and outdoor temperature is performed again. 1 from the start of this control
If the time has not elapsed, the reheat dry (standard) operation is continued.

Returning to the area determination in step S1, if the indoor temperature is in the area (I) and the outdoor temperature is in the area (b),
When the indoor temperature is in the area (I) and the outdoor temperature is in the area (c), the indoor temperature is in the area (II) and the outdoor temperature is in the area (C).
In (b), in these cases, it is considered that the mid-spring / autumn mold / mite prevention mode was selected.

In the mold / tick prevention mode, first, in step S7, the room humidity is set to 45% or less or 40% or less.
It is determined whether this is the case (see FIG. 7). If it is determined that the indoor humidity is 40% or more, the process proceeds to step S8 to start the reheating dry (standard) operation (pattern B shown in FIG. 6), and it is determined that the indoor humidity is 45% or less. If so, the process proceeds to step S9, and the reheating dry (thermo) operation is started. In the reheat dry (thermo) operation, both the compressor 12 and the propeller fan 15 are stopped, and the tangential fan 24 is rotated at a low speed.

After the reheat dry (standard) operation is started, it is determined in step S10 whether three minutes have elapsed since the start of the operation. If three minutes have elapsed, the process proceeds to step S11, and three minutes have elapsed. If not, reheating dry (standard) operation is continued.

After the start of the reheat dry (thermo) operation, it is determined in step S12 whether three minutes have elapsed since the start of the operation. If three minutes have elapsed, the process proceeds to step S11, and three minutes have elapsed. If not, reheat dry (thermo)
Operation is continued.

In step S11, it is determined whether or not one hour has elapsed since the start of the present control. If one hour has elapsed, the process returns to step S1 and the area determination for the current indoor temperature and outdoor temperature is performed again. Done. If one hour has not elapsed, the process returns to step S7, and the area determination of the indoor humidity is performed again.

Returning to the area determination in step S1, if the indoor temperature is in the area (II) and the outdoor temperature is in the area (c), it is determined that the mode has been selected in summer in this case.

In the comfortable mode, first, in step S12
The room is in a low humidity condition of 60% or less
It is determined whether it is in a high humidity state of 5% or more (see FIG. 8). If it is determined that the room is in the low humidity state, the process proceeds to step S13, where the indoor humidity is re-determined. If it is determined that the room is in the high humidity state, the reheat dry operation is started to reduce the humidity. And the normal cooling operation (step S14) is started.

After starting the cooling operation in step S14, the current room temperature (TIon ') is compared with the room temperature at the start of the main control in step S15, and the current room temperature is subtracted from the room temperature at the start of the main control minus 3 ° C. If this is the case, the cooling operation is stopped, the process proceeds to step S13, and the indoor humidity is re-determined. If the current room temperature is lower than the room temperature at the start of this control minus 3 ° C., the cooling operation is continued.

In step S13, it is determined whether the room humidity is 55% or less or 50% or more (see FIG. 9). If it is determined that the room humidity is 50% or more, the process proceeds to step S16 to start the reheating dry (standard) operation, and if it is determined that the room humidity is 55% or less, the process proceeds to step S17 and restarts. Thermal dry (thermo) operation is started.

After starting the reheat dry (standard) operation, it is determined in step S18 whether or not three minutes have elapsed since the start of the operation. If three minutes have elapsed, the process proceeds to step S19, and three minutes have elapsed. If not, reheating dry (standard) operation is continued.

After the reheat dry (thermo) operation is started, it is determined in step S20 whether or not three minutes have elapsed since the start of the operation. If three minutes have elapsed, the process proceeds to step S19, and three minutes have elapsed. If not, reheat dry (thermo)
Operation is continued.

In step S19, it is determined whether or not one hour has elapsed since the start of the present control. If one hour has elapsed, the process returns to step S1 and the area determination for the current indoor temperature and outdoor temperature is performed again. Done. If one hour has not elapsed, the process returns to step S13, and the area determination of the indoor humidity is performed again.

In the above air conditioner, the dehumidification mode is selected based on the area determination in step S1 at the start of the reheat dry operation. The indoor unit 20 side determines which dehumidification mode is selected. Users are notified. Indoor unit 20
Is provided with a display panel 27 for displaying the indoor temperature during normal heating operation and cooling operation. The display panel 27 includes a plurality of LED lamps (display unit) 28.
They are arranged in rows, and the indoor temperature is represented by the number of lighting of the LED lamps 28.

During the reheat dry operation, the number of lighting of the LED lamp 28 indicates which of the "condensation prevention mode", the "mold / mite prevention mode" and the "comfort mode" has been selected.
For example, as shown in FIGS. 10A to 10C, when the dew condensation prevention mode is selected, only one LED lamp 28 is turned on,
LED lamp 28 if mold / tick prevention mode is selected
Are turned on, and three LED lamps 28 are turned on when the comfortable mode is selected.

According to the air conditioner of the present invention configured as described above, the user only needs to select the dry operation without performing the operation of selecting the operation mode.
Any of the "Condensation prevention mode", "Mould / mite prevention mode", and "Comfort mode" are automatically selected and executed, and an appropriate dry state can be obtained according to the season. In addition, since the operation mode that matches the season is selected, the temperature of indoor and outdoor air is constantly monitored, so that excessive operation is not performed and power consumption is reduced to save energy. Can also be planned.

In the present embodiment, the propeller fan 1 in addition to the compressor 12 during the reheating dry operation.
5. Although the tangential fan 24 is also controlled to change the operation state, the compressor 12 alone may be controlled, and the propeller fan 15 and the tangential fan 24 may be operated in a steady state.

[0043]

As described above, according to the air conditioner of the present invention, the current indoor temperature and outdoor temperature are detected during the reheating and dry operation, and are set in advance based on the detection results. The user selects an appropriate operation mode from among the multiple operation modes of the reheat dry operation, and changes the operating state of the compressor so that the indoor humidity approaches the target humidity of the selected mode. Even if the operation for selecting the mode is not performed one by one, just selecting the dry operation automatically selects and executes an appropriate operation mode according to the season. As a result, the operability of the remote controller and the operation unit can be improved, and an air conditioner that can be easily handled by children and the elderly can be provided.

According to the air conditioner of the second aspect,
By changing the operation state of the outdoor fan and the indoor fan along with the change in the operation state of the compressor, the dry operation pattern is selected according to the set temperature and the current indoor temperature and humidity, and the indoor temperature is selected. In addition, it is possible to shift the humidity and humidity to a desired state more quickly, thereby obtaining a comfortable indoor environment and saving energy by shortening the operation time.

According to the air conditioner of the third aspect,
If the indoor humidity is higher than a predetermined value when the reheat dry operation is instructed, the indoor humidity is shifted to a desired state more quickly by temporarily performing the cooling operation before the start of the reheat dry operation. As a result, a comfortable indoor environment can be obtained, and energy saving can be achieved by shortening the operation time.

According to the air conditioner of the fourth aspect,
At the time of reheating dry operation, the degree of comfort in the room is determined according to the current values of temperature and humidity in the room, and the determination result is expressed by the number of indications on the display unit, so that the user can visually check the indoor state. You can see and recognize. A user who knows that the room is in a desired state can use the power wisely and wisely, for example, by stopping the air conditioner itself, thereby helping to save energy.

[Brief description of the drawings]

FIG. 1 is a plan view showing a system configuration of an air conditioner according to the present invention.

FIG. 2 is a flowchart showing a control flow during a reheating dry operation of the air-conditioning apparatus according to the present invention.

FIG. 3 is a flowchart showing the flow of control during a reheat dry operation of the air-conditioning apparatus according to the present invention.

FIG. 4 is a chart showing criteria for comparing a current indoor temperature with an outdoor temperature.

FIG. 5 is an object table for determining an operation pattern of the air conditioner.

FIG. 6 is a table showing the contents of three operation patterns.

FIG. 7 is a table showing criteria for judging a region of indoor humidity in a mold / mite prevention mode.

FIG. 8 is a table showing criteria for judging a region of indoor humidity in a comfort mode.

FIG. 9 is also a chart showing criteria for judging the area of indoor humidity in the comfort mode.

FIG. 10 is a state explanatory diagram showing a display example of an operation mode by an LED lamp during a dry operation.

[Description of Signs] 10 outdoor unit 11 outdoor heat exchanger 12 compressor 14 electromagnetic expansion valve 15 propeller fan (outdoor fan) 16 outdoor temperature sensor 20 indoor unit 21 indoor heat exchanger (first indoor heat exchanger) 22 Indoor heat exchanger for heat drying (second indoor heat exchanger) 23 Solenoid valve for drying 24 Tangential fan (Indoor fan) 25 Room temperature sensor 26 Humidity sensor 27 Display panel 28 LED lamp (Display unit) 30 Refrigerant pipe

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kei Matsuda 3-1-1 Asahicho, Nishibiwajima-cho, Nishi-Kasugai-gun, Aichi Prefecture Inside Air Conditioning Works of Mitsubishi Heavy Industries, Ltd. 3-chome, 1-chome Mitsubishi Heavy Industries, Ltd. Air Conditioning Works F-term (reference) 3L060 AA07 CC02 CC03 DD07 EE02 EE05 EE06

Claims (4)

[Claims] An outdoor heat exchanger for exchanging heat between outdoor air and a refrigerant, and a first indoor heat exchanger for exchanging heat between the outdoor heat exchanger or indoor air and a refrigerant. An outdoor unit including a compressor that sends a refrigerant to the outdoor heat exchanger and an outdoor fan that allows outdoor air to flow through the outdoor heat exchanger; the first indoor heat exchanger; and the same as the first indoor heat exchanger. A second indoor heat exchanger that performs heat exchange between indoor air and a refrigerant, an electromagnetic valve provided between the first and second indoor heat exchangers, and the first and second indoor heat exchangers. And an indoor unit having an indoor fan that allows indoor air to flow through the indoor heat exchanger. The throttle unit squeezes the solenoid valve to function as an expansion valve, and the first indoor heat exchanger absorbs heat in the refrigerant. Dehumidifies indoor air and exhausts heat from the refrigerant in the second indoor heat exchanger. An air conditioner capable of reheating dry operation that supplies air indoors after heating the air, detects the current indoor temperature and outdoor temperature during the reheat dry operation, and based on the detection result, An appropriate mode is selected from a plurality of preset reheat dry operation modes, and the operating state of the compressor is changed so that the indoor humidity approaches the target humidity of the selected mode. And air conditioners. 2. With the change in the operating state of the compressor,
The air conditioner according to claim 1, wherein the operation states of the outdoor fan and the indoor fan are also changed. 3. When the reheat dry operation is instructed, if the indoor humidity is higher than a predetermined value, a cooling operation is temporarily performed before the start of the reheat dry operation. 3. The air conditioner according to 1 or 2. 4. The indoor unit is provided with a plurality of blinking display units, and a selected reheating dry operation mode is represented by an explicit number of the display units. The air conditioner as described in the above.