JP3170556B2 - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioner capable of comfortable dehumidification having no coldness. SOLUTION: A compressor and an electric expansion valve are controlled and a dehumidifying operation is carried out so that the evaporation of a refrigerant is completed in an auxiliary indoor heat exchanger 7 of the auxiliary indoor heat exchanger 7 and a main indoor heat exchanger 8 which constitute an indoor heat exchanger. During this dehumidifying operation, air supplied from the outlet port 4 of an indoor unit 1 forms a shortcircuit in which the air is directly supplied to inlet ports 2. The shortcircuit is formed so that the dehumidification is achieved without supplying wind to an accommodation space.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner having a dehumidifying operation function.

[0002]

2. Description of the Related Art An air conditioner includes a compressor, an outdoor heat exchanger,
A room can be cooled by providing a refrigeration cycle for sequentially connecting an expansion mechanism and an indoor heat exchanger to circulate a refrigerant, and making the outdoor heat exchanger function as a condenser and the indoor heat exchanger as an evaporator. In addition, with cooling, moisture in the air is condensed in the indoor heat exchanger, so that the room can be dehumidified.

[0003]

In the season when the room temperature is not so high and the humidity is high, dehumidification itself is more desirable than cooling. However, in the conventional cooling operation and dehumidifying operation, since the entire indoor heat exchanger is used as an evaporator,
Since the room air is cooled together with the dehumidification, the room temperature is lowered and a feeling of cool air in the living area is generated.

[0004] The present invention has been made in view of the above circumstances,
An air conditioner according to a first aspect of the present invention is capable of performing dehumidification without allowing wind to reach a living area, and has an object to enable comfortable dehumidification without a feeling of cool wind.

[0005] The air conditioners of the second and third inventions have the object of performing the dehumidification with less decrease in the room temperature in addition to the object of the first invention. The air conditioner of the fourth invention is:
In addition to the object of any of the first to third aspects of the invention, it is another object of the present invention to reliably form a short circuit in which air flows from an outlet to an inlet.

An air conditioner according to a fifth aspect of the present invention, in addition to the objects of the first or second aspect, has an object to prevent a situation in which cool air is blown into a room during dehumidification. An air conditioner according to a sixth aspect of the present invention has the object of effectively utilizing the space in the indoor unit in addition to the object of the fifth aspect.

[0007] The air conditioners of the seventh and eighth inventions have the object of enabling the dehumidification operation to be used as weak cooling in addition to the object of the first invention. An air conditioner according to a ninth invention has the object of any one of the first, seventh, and eighth inventions,
An object is to ensure the formation of a short circuit in which air flows from an outlet to an inlet.

An air conditioner according to a tenth aspect of the present invention comprises the first and seventh air conditioners.
In addition to the object of any one of the eighth and eighth aspects of the invention, it is another object of the present invention to reliably and smoothly form a short circuit in which air flows from an outlet to an inlet.

An air conditioner according to an eleventh aspect of the present invention provides the air conditioner according to any one of the first, seventh, eighth, and tenth aspects, in addition to the object of the first aspect, when forming a short circuit in which air flows from an outlet to a suction port. An object is to prevent dew condensation on the lower surface of the wind direction changing plate.

[0010]

An air conditioner according to a first aspect of the present invention comprises a refrigeration cycle in which a compressor, an outdoor heat exchanger, an expansion mechanism, and an indoor heat exchanger are sequentially connected, and indoor air to an indoor heat exchanger. An indoor fan that accommodates the indoor fan and the indoor heat exchanger, and has an indoor air inlet and an air outlet through the indoor heat exchanger; A cooling direction or a dehumidifying cycle in which the provided wind direction change plate and the refrigerant discharged from the compressor return to the compressor through the outdoor heat exchanger, the expansion mechanism, and the indoor heat exchanger to form a cooling cycle or a dehumidifying operation. Operating means for selectively performing the above operation, and an operating means for forming a short circuit in which the air blown from the outlet of the indoor unit flows through the inlet of the indoor unit by operating the wind direction changing plate during the dehumidifying operation. Provided with a door.

[0011] In the air conditioner according to a second aspect of the present invention, in the first aspect, the control means controls the compressor and the expansion mechanism so that the evaporation of the refrigerant is completed in a part of the indoor heat exchanger during the dehumidifying operation. .

According to a third aspect of the present invention, in the air conditioner according to the first aspect, the indoor heat exchanger is divided into an evaporator and a reheater, and the control means performs dehumidification by the evaporator during the dehumidification operation. Is completed, and the compressor and the expansion mechanism are controlled to heat with the reheater.

The air conditioner according to a fourth aspect of the present invention is the air conditioner according to any one of the first to third aspects, further comprising a fan speed control means for operating the indoor fan at a low speed when the short circuit is formed by the operation means.

An air conditioner according to a fifth aspect of the present invention is the air conditioner according to the first to third aspects, further comprising a heater for heating the air passing through the indoor heat exchanger. An air conditioner according to a sixth aspect is the air conditioner according to the fifth aspect, wherein the indoor unit has a suction port on a front surface and an upper surface, and the indoor heat exchanger is divided into a first heat exchanger and a second heat exchanger. The two heat exchangers are arranged in an inverted V shape so as to surround the indoor fan, and the first heat exchanger is opposed to the suction port on the front face, and the second heat exchanger is opposed to the suction port on the top face, A heater was provided in a space between the first and second heat exchangers and the indoor fan.

According to a seventh aspect of the present invention, in the air conditioner according to the first aspect, the operating means operates the wind direction changing plate after a predetermined time from the start of operation. An air conditioner according to an eighth aspect of the present invention is the air conditioner according to the first aspect, further comprising a temperature detecting means for detecting the indoor temperature Ta, and operating the wind direction changing plate when the detected temperature Ta decreases by a predetermined value after the start of operation. I do.

An air conditioner according to a ninth aspect of the present invention has the first, seventh,
In any one of the eighth and eighth inventions, the wind direction changing plate comprises a lower wind direction changing plate and a left and right wind direction changing plate, and the operating means includes:
The short circuit is formed by operating the vertical wind direction changing plate, and at the same time, the left and right wind direction changing plate is operated so that the blown wind is concentrated at the center.

The air conditioner according to a tenth aspect of the present invention is the air conditioner according to any one of the first, seventh, and eighth aspects, wherein the wind direction change plate has an elevation angle with respect to a horizontal line at an upper surface tangent of a front edge when forming a short circuit. It has an eggplant shape.

An air conditioner according to an eleventh aspect of the present invention is the air conditioner according to any one of the first, seventh, eighth, and tenth aspects, wherein the wind direction change plate is arranged such that a tangent to a lower surface of a rear edge portion is horizontal when forming a short circuit. It has a shape that makes an elevation angle to it.

In short, in the air conditioner of the first invention,
During the dehumidifying operation, a short circuit is formed in which the air blown from the outlet of the indoor unit flows to the inlet as it is.

In the second air conditioner, during the dehumidifying operation, the evaporation of the refrigerant ends in a part of the indoor heat exchanger. In the air conditioner of the third invention, during the dehumidifying operation, the evaporation of the refrigerant ends in the evaporator portion of the evaporator portion and the reheater portion of the indoor heat exchanger.

In the air conditioner of the fourth invention, the indoor fan is operated at a low speed when the short circuit is formed. In the air conditioner of the fifth invention, the air that has passed through the indoor heat exchanger is heated by the heater as needed.

In the air conditioner of the sixth invention, the heater is housed in the space between the first heat exchanger and the second heat exchanger in the indoor unit and the indoor fan. In the air conditioner of the seventh invention, a short circuit is formed after a predetermined time from the start of the dehumidifying operation.

In the air conditioner of the eighth invention, a short circuit is formed when the room temperature Ta drops by a predetermined value after the start of the dehumidifying operation. In the air conditioner of the ninth aspect, a short circuit is formed by the vertical wind direction changing plates, and the left and right wind direction changing plates are operated to concentrate the blown air at the center so as to assist the formation.

In the air conditioner of the tenth aspect, the flow of air along the upper surface of the wind direction change plate is directed upward, so that the short circuit is reliably and smoothly formed. In the air conditioner according to the eleventh aspect, air flows along the lower surface of the wind direction changing plate without separating from the lower surface, and no dew condensation occurs on the lower surface.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 1 denotes an indoor unit, which has a suction port 2 for indoor air on the front surface, a suction port 3 for indoor air on the top surface, and air conditioning air (cooling air, dehumidifying air, heating (Air, etc.).

In the indoor unit 1, the suction ports 2, 3
To the outlet 4 to form a ventilation path 5. In the ventilation passage 5, a dustproof (and deodorizing) filter 6 is provided inside the suction ports 2 and 3, and a main indoor heat exchanger 8 and an auxiliary indoor heat exchanger 7 are arranged inside the filter 6. Is established. Then, a horizontal flow type indoor fan 9 is disposed inside the heat exchangers 7 and 8.

The main indoor heat exchanger 8 is divided into a first heat exchanger 8a and a second heat exchanger 8b.
b is arranged in an inverted V shape so as to surround the indoor fan 9.
The first heat exchanger 8a faces the suction port 2 on the front face, and the second heat exchanger 8b faces the suction port 3 on the top face. The auxiliary indoor heat exchanger 7 is disposed between the second heat exchanger 8b and the suction port 3, that is, at a position on the windward side above the second heat exchanger 8b in the indoor air suction flow path. .

In the space between the heat exchangers 8a and 8b and the indoor fan 9, an electric heater 17 and a drainage member 18 are provided. The electric heater 17 is for heating the air passing through the heat exchangers 8a and 8b as needed. The drainage member 18 is for preventing the drain from directly falling on the electric heater 17 even if the drain drips from the heat exchangers 8a and 8b.

The drain receiving portion 1 is located below the first heat exchanger 8a.
9 is formed. A drain receiving portion 19 is also formed below the second heat exchanger 8b and the auxiliary indoor heat exchanger 7. The radiating fins of the first heat exchanger 8a and the radiating fins of the second heat exchanger 8b are in contact with each other, but between the radiating fins of the second heat exchanger 8b and the radiating fins of the auxiliary indoor heat exchanger 7. Is in a state where both heat radiation fins are not in contact with each other, that is, thermally separated from each other.

When the indoor fan 9 rotates, the indoor air passes through the suction port 2 and the suction port 3, respectively, and the indoor unit 1
It is sucked in. The suction air from the suction port 2 passes through the filter 6 and further flows through the first heat exchanger 8a to the indoor fan 9 side. After passing through the filter 6, the suction air from the suction port 3 first flows through the auxiliary indoor heat exchanger 7, and then flows through the second heat exchanger 8b to the indoor fan 9 side.

In the ventilation path 5, a left / right air direction change plate 10 is provided at a position facing the air outlet 4 on the downstream side of the indoor fan 9. The left and right wind direction change plates 10 are for setting the direction of the blown wind in the left and right direction of the indoor unit 1 and are motor driven.

On the downstream side of the left and right wind direction change plates 10, a plurality of, for example, a pair of upper and lower wind direction change plates 11, 11 are provided vertically. The vertical wind direction change plates 11 and 11 are driven by a single motor in conjunction with each other, and rotate clockwise during operation to open the air outlet 4 during operation, and change the direction of the blown air in the vertical direction of the indoor unit 1. When the operation is stopped, it rotates counterclockwise to close the air outlet 4, and functions to prevent dust from entering the indoor unit 1.

On the other hand, as shown in FIG. 2, an outdoor heat exchanger 23 is connected to the discharge port of the compressor 21 via a four-way valve 22 by piping, and an expansion mechanism such as an electric expansion valve 24 is connected to the outdoor heat exchanger 23. Piping is connected. The degree of opening of the electric expansion valve 24 continuously changes in accordance with the number of input drive pulses.

One end of the auxiliary indoor heat exchanger 7 is connected to the motor-operated expansion valve 24 via a pipe, and the other end of the auxiliary indoor heat exchanger 7 is connected to the main indoor heat exchanger 8 (the first heat exchanger 8a and the second heat exchanger 8a). The vessel 8b) is connected by piping. And the main indoor heat exchanger 8
The suction port of the compressor 1 is connected via a pipe to the four-way valve 2.

Thus, a heat pump refrigeration cycle capable of cooling, dehumidifying, and heating is configured. At the time of cooling, the refrigerant discharged from the compressor 1 flows from the four-way valve 22 to the outdoor heat exchanger 23, the electric expansion valve 24, the auxiliary indoor heat exchanger 7, and the main indoor heat exchanger 8, as indicated by solid arrows in the drawing. , And a cooling cycle in which the refrigerant having passed through the main indoor heat exchanger 8 returns to the compressor 1 through the four-way valve 22 is formed. That is, the outdoor heat exchanger 23 functions as a condenser, and the auxiliary indoor heat exchanger 7 and the main indoor heat exchanger 8 function as an evaporator.

At the time of dehumidification, a dehumidification cycle in which the refrigerant flows in the same direction as during cooling is formed. During heating, the four-way valve 22 is switched so that the refrigerant discharged from the compressor 1 flows from the four-way valve 22 to the main indoor heat exchanger 8, the auxiliary indoor heat exchanger 7, A cycle is formed in which the refrigerant flows sequentially to the valve 24 and the outdoor heat exchanger 23 and passes through the outdoor heat exchanger 23 and returns to the compressor 1 through the four-way valve 22. That is, the auxiliary indoor heat exchanger 7 and the main indoor heat exchanger 8 function as a condenser, and the outdoor heat exchanger 23 functions as an evaporator.

As shown in both FIG. 1 and FIG. 2, a heat exchanger temperature sensor 13 is attached to the heat exchange pipe on the outlet side of the auxiliary indoor heat exchanger 7, and the heat in the intermediate portion of the first heat exchanger 8a. A heat exchanger temperature sensor 14 is attached to the exchange pipe.

An indoor temperature sensor 15 is provided in an indoor air suction passage extending from the suction port 2 to the main indoor heat exchanger 8. The outdoor fan 25 is located near the outdoor heat exchanger 23.
Is provided. The outdoor fan 25 supplies outdoor air to the outdoor heat exchanger 23.

The commercial AC power supply 30 has an inverter circuit 3
1. The speed control circuits 32 and 33 and the control unit 40 are connected. Then, the control unit 40 includes an inverter circuit 31,
Speed control circuits 32 and 33, wind direction changing plate motor 10M,
11M, heat exchanger temperature sensors 13 and 14, indoor temperature sensor 15, electric heater 17, four-way valve 22, electric expansion valve 2
4 and the light receiving unit 41 are connected.

The inverter circuit 31 rectifies the power supply voltage, converts the power supply voltage into an alternating current having a frequency F (and voltage) according to a command from the control unit 40, and outputs the alternating current. This output is the drive power of the drive motor (compressor motor) of the compressor 21.

The speed control circuit 32 controls the outdoor fan motor 2
By controlling the supply of the power supply voltage to 5M (for example, energizing phase control), the speed of the outdoor fan motor 25M (the amount of air blown by the outdoor fan 25) is set to a speed according to a command from the control unit 40. The speed control circuit 33 sets the speed of the indoor fan motor 9M (the amount of air blown by the indoor fan 9) to a speed according to a command from the control unit 40 by controlling the supply of the power supply voltage to the indoor fan motor 9M (for example, energizing phase control). I do.

The light receiving section 41 receives infrared light transmitted from a remote control type operation device (hereinafter, abbreviated as a remote control) 42. The control unit 40 performs overall control of the air conditioner, and includes the following [1] to [3] as main functional means.

[1] A cooling or dehumidifying cycle in which the refrigerant discharged from the compressor 21 returns to the compressor through the outdoor heat exchanger 23, the electric expansion valve 24, the auxiliary indoor heat exchanger 7, and the main indoor heat exchanger 8 A control unit that is formed and selectively executes one of a cooling operation and a dehumidifying operation.

[2] During the dehumidifying operation, the vertical wind direction changing plate 11,
The air blown from the outlet 4 by operating the suction port 11
Operating means for forming a short circuit flowing through. [3] Fan speed control means for operating the indoor fan 9 at a low speed when a short circuit is formed by the operation means.

Next, the operation of the above configuration will be described with reference to the flowchart of FIG. When the dehumidification mode is set by the remote controller 42 and an operation for starting the operation is performed, the compressor 21 is started to form a dehumidification cycle, and the operation of the indoor fan 9 and the outdoor fan 25 is started to start the dehumidification operation. Becomes

The operation frequency F of the compressor 21 is a predetermined value (for example, 16
Hz), and thereafter, is gradually lowered at predetermined time intervals to a predetermined minimum operation frequency Fmin (for example, 9 Hz).

Simultaneously with the operation frequency control, the opening degree of the electric expansion valve 24 is controlled so that the evaporation of the refrigerant is completed in the auxiliary indoor heat exchanger 7 and the refrigerant enters the superheated region in the main indoor heat exchanger 8. .

Specifically, the difference between the temperature Tc of the main indoor heat exchanger 8 detected by the heat exchanger temperature sensor 14 and the temperature Tj of the auxiliary indoor heat exchanger 7 detected by the heat exchanger temperature sensor 13 ΔTcj (= Tc-Tj) is to be the predetermined value DerutaTcj _1, moreover detected temperature Tj so that is below the suction air dew point temperature, the opening degree of the electric expansion valve 24 is controlled. The predetermined value ΔTcj ₁ is a value proportional to the operating frequency F of the compressor 21.

For example, when the temperature difference ΔTcj is a predetermined value ΔTcj ₁
If it is larger, the opening of the electric expansion valve 24 is reduced by a predetermined value for each control loop. The temperature difference ΔTcj is a predetermined value ΔT
smaller than cj _1, the opening degree of the electric expansion valve 24 is increased by a predetermined value for each control loop. If the temperature difference DerutaTcj matches a predetermined value ΔTcj _1, the opening degree of the electric expansion valve 24 at that time is held as it is.

By this opening degree control, the intake air is cooled and dehumidified almost only in the auxiliary indoor heat exchanger 7, and is blown into the room without heat exchange in the main indoor heat exchanger 8. Moisture adhering to the auxiliary indoor heat exchanger 7 drops along the heat exchange pipe and the radiation fins of the heat exchanger 7 to the drain receiving portion 19.

Here, the dehumidifying action of the auxiliary indoor heat exchanger 7 will be described. When the operating frequency F increases,
The circulation amount of the refrigerant increases. If the target value ΔTcj _{1 of the} temperature difference ΔTcj is constant for any operating frequency F, the refrigerant circulation amount increases, so that the evaporation of the refrigerant is completed only by the auxiliary indoor heat exchanger 7. Instead, the evaporation of the refrigerant also occurs in the main indoor heat exchanger 8. In this case, not only the function of dehumidification but also the function of cooling (that is, lowering the temperature of indoor air) is exhibited.

The temperature difference ΔTcj according to the change of the operating frequency F
Can be changed, the evaporation of the refrigerant can be terminated only by the auxiliary indoor heat exchanger 7 even if the refrigerant circulation amount increases. Therefore, the predetermined value ΔTcj _{1 is changed} to the operation frequency F
It is set to a value proportional to. This allows
Irrespective of the change in the compression function force, the dehumidifying action is given only to the auxiliary indoor heat exchanger 7, so that the decrease in the indoor temperature can be surely suppressed.

FIG. 4 is a Mollier diagram showing the relationship between the temperature Tj of the auxiliary indoor heat exchanger 7, the temperature Tc of the main indoor heat exchanger 8, and the temperature difference ΔTcj. If the temperature difference DerutaTcj predetermined value DerutaTcj ₁ less than the temperature of the auxiliary indoor heat exchanger 7 (i.e. evaporation temperature) Tj is determined to be in the state higher, in a direction to narrow the opening degree of the electric expansion valve 24 Control.

When the opening of the motor-operated expansion valve 24 is reduced, the evaporating pressure drops and the evaporating temperature Tj decreases, and the difference between the evaporating temperature Tj and the suction air temperature Ta increases. This allows
The heat exchange between the refrigerant and the air in the auxiliary indoor heat exchanger 7 is promoted, and the evaporation of the refrigerant ends only in the auxiliary indoor heat exchanger 7. At this time, the superheated area of the refrigerant becomes large, and all of the main indoor heat exchangers 8 become superheated areas.
Tc approaches the intake air temperature Ta. That is,
No cooling action occurs in the main indoor heat exchanger 8.

Further, according to this control, the evaporation temperature Tj is greatly reduced as compared with the case where the refrigerant is evaporated by the entire indoor heat exchanger (auxiliary indoor heat exchanger 7 + main indoor heat exchanger 8) as in cooling. be able to.

That is, assuming that the refrigerant evaporates in the entire indoor heat exchanger, if the evaporation temperature is greatly reduced to below the dew point temperature of the intake air in order to obtain the dehumidifying capacity, the temperature of the air blown into the room increases greatly. Will go down. In the psychrometric chart of FIG. 5, the suction air temperature is shown at point A. In order to prevent the blow-off air temperature from dropping, the evaporation temperature is limited to, for example, point C (15 degrees).

On the other hand, if the dehumidification is performed only by the auxiliary indoor heat exchanger 7, even if the evaporation temperature is lowered to the point C 'with respect to the suction air temperature A, the main indoor heat exchange except the auxiliary indoor heat exchanger 7 is performed. Since the temperature Tc of the container 8 is the air temperature, the room temperature is not easily lowered. That is, the dehumidifying capacity can be increased without lowering the room temperature.

When the area of the heat exchanger is small as in the auxiliary indoor heat exchanger 7, even if the evaporation temperature is greatly reduced,
It is considered that sufficient dehumidifying capacity may not be obtained. For example, the auxiliary indoor heat exchanger 7 and the main indoor heat exchanger 8
Assuming that the ratio of the area of the heat exchanger to the heat exchanger is 1: 5, the ratio of the area of the auxiliary indoor heat exchanger 7 to the area of the entire indoor heat exchanger is 1/6, which is almost 1/6. If there is a difference between the dew point temperature and the evaporation temperature in the value corresponding to the reciprocal, the same amount of moisture as in the case of dehumidifying the entire indoor heat exchanger is condensed.
That is, the dehumidifying ability substantially equal to the case where the entire indoor heat exchanger is dehumidified is obtained.

In the psychrometric chart of FIG. 5, the line AB and the line A-
Components X and X 'perpendicular to each isenthalpy line of B' line
Indicates the latent heat cooling capacity (the amount of heat for changing the moisture in the air from water vapor to water droplets), and the components Y and Y 'perpendicular to the respective isenthalpy lines of the BC line and the BC' line are sensible heat Indicates the cooling capacity (the amount of heat for the air to lower the temperature).

As can be seen from this figure, the latent heat ratio of the ratio of the latent heat to the sensible heat in this embodiment is larger than the latent heat ratio of the ratio of the latent heat to the sensible heat when the entire indoor heat exchanger performs heat exchange. . (X / Y) <(X ′ / Y ′).

Therefore, a sufficient dehumidifying capacity can be obtained without lowering the temperature of the blown air unlike during cooling. Incidentally, simultaneously with the start of the time count t of the dehumidifying operation is started, when the time count t has reached the predetermined time t _1, as shown by the broken line in FIG. 1, the front edge of the vertical airflow direction changing plate 11, 11 It is rotated to a position above the horizontal line. As a result, a short circuit is formed in which the air blown from the outlet 4 flows through the inlet 2 as it is, and the blown air does not reach the living area.

Therefore, dehumidification can be continued without allowing the wind to reach the living area, and comfortable dehumidification without the feeling of cool wind can be achieved. Although some air is continuously sucked in by the short circuit, the diffusion rate of moisture in the air is sufficiently high, and the air in the living area is sufficiently dehumidified by diffusion.

At the same time as the formation of this short circuit,
The indoor fan 9 is operated at a low speed. By this low-speed operation, the air blown out from the outlet 4 flows to the inlet 2 without flowing far, and the formation of a short circuit is ensured.

The moisture in the air moves by diffusion, not by air flow. From this, even if the indoor fan 9 is stopped during the dehumidifying operation, the dehumidifying ability is not impaired. However, if the indoor fan 9 is stopped, the cool air flows through the gap between the air outlet 4 and the vertical wind direction change plates 11, 11. Is lowered, and the indoor fan 9 is operated at a low speed, including preventing this.

The certain time t ₁ from the start of the dehumidifying operation to the formation of the short circuit is an approximate time required for a person in the living area to feel a cool wind. In consideration of the fact that some people use the dehumidifying operation as weak cooling, normal blowing is performed without forming a short circuit until a feeling of cool air is generated.

In forming a short circuit, the left and right wind direction change plates 10 are set at the left and right center positions at the same time as the vertical wind direction change plates 11 and 11 are moved. Since the air blown out from the outlet 4 tends to expand in the left-right direction, there is a concern that the formation of the short circuit is impaired. Therefore, the left and right wind direction change plate 10 is operated so that the blown wind is concentrated at the center, thereby avoiding air leakage in the left and right directions, thereby ensuring the formation of a short circuit.

Focusing on the operating frequency F of the compressor 21,
The cooling operation is performed as the actual value of the operating frequency F because the evaporation of the refrigerant is controlled only by the auxiliary indoor heat exchanger 7 and the dehumidifying operation itself is often selected in a season when the indoor temperature is not so high. A much lower value is chosen than at times. Therefore, power consumption can be reduced and an energy saving effect can be obtained.

Since a clearance is secured between the radiating fins of the auxiliary indoor heat exchanger 7 and the radiating fins of the main indoor heat exchanger 8, the two radiating fins are in a non-contact state, that is, in a thermally separated state. Therefore, a sufficient temperature difference can be secured between the auxiliary indoor heat exchanger 7 serving as an evaporating area and the main indoor heat exchanger 8 serving as an overheating area, so that a high dehumidifying capacity can be ensured.

Regarding the configuration of the indoor unit 1, there is a suction port 2 on the front face and a suction port 3 on the top face, and the first and second heat exchangers 8a and 8a of the main indoor heat exchanger 8 are provided on these suction ports 2 and 3. 2
The two heat exchangers 8a and 8b are arranged in an inverted V-shape so as to surround the indoor fan 9 with the heat exchangers 8b facing each other, and between the second heat exchanger 8b and the suction port 3 on the upper surface. Since the auxiliary indoor heat exchanger 7 is disposed in the main unit, a good ventilation path for the auxiliary indoor heat exchanger 7 and the main indoor heat exchanger 8 can be secured while avoiding an increase in the size of the indoor unit 1. Thereby, the heat exchange efficiency between the refrigerant and the intake air is improved, and an energy saving effect is obtained.

When the electric heater 17 is operated, the air passing through the auxiliary indoor heat exchanger 7 and the heat exchangers 8a and 8b can be heated. Thereby, the temperature of the blown air can be adjusted, and it is possible to reliably prevent a situation in which cool air is blown into the room during dehumidification. In addition, since the space existing between the heat exchangers 8a and 8b and the indoor fan 9 is used as a position for disposing the electric heater 17, a special space needs to be provided only for disposing the electric heater 17. Since the space inside the indoor unit 1 is effectively used and the space is located immediately below each of the vertices of the heat exchangers 8a and 8b, the drain suction port does not drop to the electric heater 17 and the drainage member 18 In addition, the safety of the electric heater 17 can be ensured. .

[0071] In the above embodiment has formed the short circuit from the start of the dehumidifying operation after a predetermined time t _1,
After the start of the dehumidifying operation, a short circuit may be formed when the indoor temperature (suction air temperature) Ta detected by the indoor temperature sensor 15 decreases by a predetermined value. Both are similar in that they wait for a short circuit to form until the inhabitants begin to feel a cool breeze.

In the above embodiment, considering the operation during the dehumidifying operation, both the auxiliary indoor heat exchanger 7 and the main indoor heat exchanger 8 are used as the evaporator during the dehumidifying operation. The main indoor heat exchanger 8 is set as an overheating area as an evaporation area where the evaporation of the refrigerant is completed at 7.

However, without being limited to this, FIG.
As shown in the figure, the indoor heat exchanger 50 is connected to the first heat exchanger 51.
And the second heat exchanger 52.
A dehumidifying method using a general evaporator and a reheater, which is connected between an expansion mechanism 53 such as a capillary tube and a two-way valve 54 and a bypass path 55 which bypasses the expansion mechanism 53 between the expansion mechanism 53 and the expansion mechanism 53. It may be a thing. In addition, the indoor heat exchanger 5
Since the refrigeration cycle other than 0 is the same as that of FIG. 2, detailed description is omitted.

During the dehumidifying operation, the electric expansion valve 24
Is fully opened, the two-way valve 54 of the bypass passage 55 is closed,
When the refrigerant flows as indicated by the solid line arrow, the suction air flows from the second indoor heat exchanger 52 to the first heat exchanger 51, and the second heat exchanger 52 acts as an evaporator to draw the suction air. The first indoor heat exchanger 51 acts as a reheater to heat the dehumidified and cooled suction air to near room temperature.

Even in such a case, if a short circuit is formed during the dehumidifying operation, dehumidification can be performed without allowing the wind to reach the living area, and comfortable dehumidification without a feeling of cool air can be achieved.

Further, the expansion mechanism 53 and the two-way valve 54 shown in FIG.
A refrigeration cycle using an electronic expansion valve instead of has the same effect. In addition, one pass or two indoor heat exchangers
Even as a general plate-shaped or "-" shaped indoor heat exchanger formed by a pass, a short circuit can be formed during dehumidification so that dehumidification can be performed without allowing wind to reach the living area. Therefore, comfortable dehumidification without a feeling of cold wind is possible.

The vertical wind direction change plates 11, 11 provided in the air outlet 4 are not limited to the flat type shown in FIG. 1, but may be a curved type shown in FIG.
The vertical wind direction change plates 11 and 11 in FIG. 7 indicate the horizontal blowing position in the solid line state and the short circuit position in the broken line state, and satisfy the conditions shown in FIG. 8 in the short circuit position.

That is, the vertical wind direction change plates 11, 11
At the front edge 11a on the side corresponding to the suction port 2 at the time of forming the short circuit, the upper surface tangent line La along the upper surface has an elevation angle of an angle α with the horizontal line. With this shape, the flow of air along the upper surfaces of the vertical wind direction change plates 11 and 11 goes upward with the suction port 2 as shown by the dashed arrow in the drawing, and the short circuit is formed reliably and smoothly.

Further, the vertical wind direction changing plates 11 and 11 have a lower surface tangent line Lb along the lower surface at the rear edge 11b on the side corresponding to the left and right wind direction changing plate 10 when forming the short circuit, with the elevation angle of the angle β with respect to the horizontal line. It has an eggplant shape. With this shape, air flows along the lower surfaces of the vertical wind direction change plates 11 and 11 without separating from the lower surfaces, and no dew condensation occurs on the lower surfaces. It is possible to prevent the condensation water from dripping into the room.

The curved shape here does not necessarily need to be used for both the vertical wind direction change plates 11, 11, and only one of them may be used. When the vertical wind direction change plates 11 and 11 are set to the blow-out position directly below as in the case of heating, the curved shape may obstruct the flow of air. As a countermeasure, as shown in FIG. 9 and FIG.
There is a configuration in which the member is divided into a member 1a and a member of the rear edge portion 11b, and both members are rotatably connected to each other, and the shape is changed around the connection portion and according to the difference in the blowing direction.

FIG. 9 shows a state in which a short circuit is formed, and the same series of curved shapes as those shown in FIG. 8 are ensured. FIG. 10 shows a blow-out position directly below, which is bent in the shape of a "ku". Due to this bending, the resistance to the flow of the blown air in the downward direction is reduced, and a sufficient blown air volume can be secured.

[0082]

As described above, the air conditioner according to the first aspect of the present invention is configured to form a short circuit in which air blown from the outlet of the indoor unit flows to the inlet as it is during dehumidification. Dehumidification can be performed without allowing the wind to reach the living area, and comfortable dehumidification without a feeling of cool wind is possible.

According to the air conditioner of the second invention, in the first invention, during the dehumidifying operation, the compressor and the expansion mechanism are controlled so that the evaporation of the refrigerant is completed in a part of the indoor heat exchanger. Further, dehumidification without lowering the room temperature can be performed.

The air conditioner according to a third aspect of the present invention is the air conditioner according to the first aspect of the present invention, wherein during the dehumidifying operation, the refrigerant is evaporated so that the evaporation of the refrigerant ends at the evaporator portion of the evaporator portion and the reheater portion of the indoor heat exchanger. Since the air cooled and dehumidified in the reheater section is heated to around room temperature by controlling the air blower and the expansion mechanism, dehumidification without lowering the room temperature can be performed.

According to the air conditioner of the fourth invention, in any one of the first to third inventions, the indoor fan is operated at a low speed when the short circuit is formed, so that air flows from the air outlet to the air inlet. The formation of a flowing short circuit is ensured.

In the air conditioner according to the fifth aspect of the present invention, in the first to third aspects, the air which has passed through the indoor heat exchanger is heated by a heater if necessary. Can be prevented from being blown out.

The air conditioner according to a sixth aspect of the present invention is the air conditioner according to the fifth aspect, wherein a heater is accommodated in a space between the first heat exchanger and the second heat exchanger in the indoor unit and the indoor fan. Therefore, the space in the indoor unit can be effectively used.

In the air conditioner according to the seventh aspect of the invention, since the short circuit is formed after a predetermined time from the start of the operation in the first aspect, the dehumidifying operation can be used as a weak cooling.

The air conditioner according to the eighth aspect of the present invention is the air conditioner according to the first aspect, wherein the short circuit is formed when the indoor temperature Ta decreases by a predetermined value after the start of operation.
The dehumidifying operation can be used as weak cooling.

The air conditioner according to the ninth invention has the first, seventh,
In any one of the eighth and eighth aspects, the short circuit is formed by the vertical wind direction changing plates, and the left and right wind direction changing plates are operated so as to concentrate the blowout wind at the center so as to assist the formation thereof. The formation of a short circuit through which air flows from the inlet to the suction port is ensured.

The air conditioner according to a tenth aspect of the present invention is the air conditioner according to any one of the first, seventh, and eighth aspects, wherein the wind direction changing plate is formed such that a tangent to an upper surface of a front edge portion forms an elevation angle with respect to a horizontal line when forming a short circuit. Because of the shape, a short circuit in which air flows from the outlet to the inlet becomes reliable and smooth.

An air conditioner according to an eleventh aspect of the present invention is the air conditioner according to any one of the first, seventh, eighth, and tenth aspects, wherein the wind direction changing plate is formed such that the tangent to the lower surface of the rear edge portion is horizontal when the short circuit is formed. Since the shape is an elevation angle, dew condensation on the lower surface of the wind direction change plate can be prevented when forming a short circuit in which air flows from the outlet to the inlet.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an internal configuration of an indoor unit according to an embodiment.

FIG. 2 is a diagram showing a configuration of a refrigeration cycle and a configuration of a control circuit according to the embodiment.

FIG. 3 is a flowchart for explaining the operation of the embodiment.

FIG. 4 is a Mollier chart of the refrigeration cycle of the embodiment.

FIG. 5 is a psychrometric chart of the refrigeration cycle of the embodiment.

FIG. 6 is a diagram showing a configuration of a modification of the refrigeration cycle of FIG. 2;

FIG. 7 is a diagram showing a configuration of a modified example of the vertical wind direction changing plate in FIG.

FIG. 8 is a diagram specifically showing a configuration of a vertical wind direction changing plate in FIG. 7;

9 is a diagram specifically showing the configuration of another modification of the vertical wind direction changing plate in FIG.

FIG. 10 is a diagram showing a state in which the vertical wind direction changing plate of FIG. 9 is set to a blow-out position immediately below.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Indoor unit, 2 ... Suction port, 3 ... Suction port, 4 ... Outlet, 5 ... Ventilation path, 7 ... Auxiliary indoor heat exchanger, 8 ... Main indoor heat exchanger, 8a ... 1st heat exchanger, 8b ... Second heat exchanger, 9
... indoor fan, 10 ... left and right wind direction change plate, 11, 11 ... vertical wind direction change plate, 11a ... front edge, 11b ... rear edge, 1
3, 14: heat exchanger temperature sensor, 15: indoor temperature sensor, 17: electric heater, 21: compressor, 22: four-way valve,
23 ... outdoor heat exchanger, 24 ... electric expansion valve, 31 ... inverter circuit, 40 ... control unit.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tetsuro Ozawa 336 Tatehara, Fuji-shi, Shizuoka Prefecture Inside Toshiba A-V E Co., Ltd. (58) Field surveyed (Int.Cl. ⁷ , DB name) F24F 11/02 102 F25B 1/00 303

Claims (11)

(57) [Claims] A refrigeration cycle in which a compressor, an outdoor heat exchanger, an expansion mechanism, and an indoor heat exchanger are sequentially connected; an indoor fan that circulates indoor air through the indoor heat exchanger; An indoor unit accommodating an indoor heat exchanger and having an indoor air inlet and an air outlet through the indoor heat exchanger; a wind direction changing plate provided at an outlet of the indoor unit; Control means for forming a cooling cycle or a dehumidifying cycle in which the discharged refrigerant returns to the compressor through the outdoor heat exchanger, the expansion mechanism, and the indoor heat exchanger, and selectively executes either the cooling operation or the dehumidifying operation; Operating means for operating the wind direction changing plate during operation to form a short circuit in which air blown from the air outlet of the indoor unit flows to the air inlet of the indoor unit. An air conditioner characterized by the above. 2. The air conditioner according to claim 1, wherein the control unit controls the compressor and the expansion mechanism so that the refrigerant evaporates in a part of the indoor heat exchanger during the dehumidifying operation. An air conditioner characterized by the following. 3. The air conditioner according to claim 1, wherein the indoor heat exchanger is divided into an evaporator and a reheater, and the control means completes dehumidification in the evaporator during a dehumidification operation. And controlling a compressor and an expansion mechanism so as to heat with a reheater. 4. The air conditioner according to claim 1, further comprising: fan speed control means for operating said indoor fan at a low speed when said operating means forms a short circuit. An air conditioner characterized by the following. 5. The air conditioner according to claim 1, further comprising: a heater for heating air passing through the indoor heat exchanger. 6. The air conditioner according to claim 5, wherein the indoor unit has a suction port on a front surface and an upper surface, and divides the indoor heat exchanger into a first heat exchanger and a second heat exchanger. Invert the two heat exchangers so as to surround the indoor fan.
And the first heat exchanger is opposed to the suction port on the front face, the second heat exchanger is opposed to the suction port on the top face, and the first heat exchanger and the second heat exchanger The air conditioner, wherein the heater is provided in a space between the indoor fan and the indoor fan. 7. The air conditioner according to claim 1, wherein the operation means operates the wind direction changing plate after a predetermined time from the start of operation. 8. The air conditioner according to claim 1, further comprising a temperature detecting means for detecting a room temperature Ta, wherein the operating means changes a wind direction changing plate when the detected temperature Ta decreases by a predetermined value after the start of operation. Operating the air conditioner. 9. The air conditioner according to claim 1, wherein the wind direction changing plate comprises a vertical direction changing plate and a horizontal direction changing plate. An air conditioner, wherein a short circuit is formed by operation of the vertical wind direction changing plate, and at the same time, the horizontal wind direction changing plate is operated so that the blown wind is concentrated at the center. 10. The method of claim 1, claim 7, and claim 8.
The air conditioner according to any one of claims 1 to 3, wherein the wind direction changing plate has a shape in which a tangent to an upper surface of a front edge portion forms an elevation angle with respect to a horizontal line when forming a short circuit. 11. The air conditioner according to any one of claims 1, 7, 8, and 10, wherein the wind direction changing plate has a lower surface tangent to a rear edge portion when forming a short circuit. An air conditioner having a shape that forms an elevation angle with respect to a horizontal line.