EP4653773A1

EP4653773A1 - Air conditioner, wind direction control method, and program

Info

Publication number: EP4653773A1
Application number: EP25177496.4A
Authority: EP
Inventors: Kazuki Kamata; Masaru Ito; Motoki Hamasaki
Original assignee: Carrier Japan Corp
Current assignee: Carrier Japan Corp
Priority date: 2024-05-24
Filing date: 2025-05-20
Publication date: 2025-11-26
Also published as: CN121007344A; JP2025177998A

Abstract

An air conditioner of an embodiment includes a suction temperature sensor, a radiation sensor, and a control unit. The suction temperature sensor measures a suction temperature which is a temperature of air sucked from a suction port of an indoor unit. The radiation sensor measures a radiation temperature which is a temperature of radiant heat from a floor surface. The control unit includes a floor-surface-temperature estimation unit and a wind-direction control unit. The floor-surface-temperature estimation unit estimates a floor surface temperature based on the radiation temperature. The wind-direction control unit controls a wind-direction adjustment member provided in each of a plurality of air outlets of the indoor unit. The wind-direction control unit performs a first wind-direction control. In the first wind-direction control, in a case in which a difference value between the suction temperature and the floor surface temperature exceeds a predetermined threshold value, a first state in which a wind direction of wind blown out from one air outlet is directed downward and a wind direction of the wind blown out from the remaining air outlets is directed in a direction closer to a horizontal direction and a second state in which all air outlets are directed downward are alternately repeated at predetermined intervals.

Description

[TECHNICAL FIELD]

The present invention relates to an air conditioner, a wind direction control method, and a program.

[BACKGROUND ART]

In order to ensure a comfortable thermal environment, it is recommended to minimize the temperature difference between the head and feet. For example, since the temperature difference can be large and the temperature around the feet can be relatively low in an office space in winter, an occupant in the room may feel uncomfortable due to the cold. In such a case, the occupant in the room may change the temperature setting of the air conditioner to a higher temperature. In such an environment, since the set temperature changed to a higher temperature may cause an excessive heating operation, a waste of energy such as electricity occurs.
Conventionally, as a technology for improving comfort by reducing the temperature difference in a space, for example, a technology described in Patent Document 1 is known. A wind direction control device of an air conditioner of Patent Document 1 controls the wind direction of all warm wind blown out from a plurality of air outlets to be downward in a case in which the temperature difference (hereinafter, referred to as "vertical temperature difference") obtained by subtracting the floor surface temperature from the temperature (suction temperature) of air sucked into the suction port of the air conditioner exceeds a predetermined value during a heating operation.
However, when the wind direction of all air outlets is simply directed downward as in the wind direction control device described in Patent Document 1, the wind volume (wind speed) becomes insufficient, and the warm wind may not reach the floor surface due to the influence of buoyancy. On the other hand, when the wind volume is increased (wind speed is increased) in order to ensure that the warm wind reaches the floor surface, the consumption of energy such as electricity increases. In this way, conventionally, there was a problem that the vertical temperature difference of the indoor space was less likely to be reduced while suppressing energy consumption.

[CITATION LIST]

[PATENT LITERATURE]

[Patent Document 1] Japanese Unexamined Patent Application, First Publication No. H02-223754

[SUMMARY OF THE INVENTION]

[PROBLEMS TO BE SOLVED BY THE INVENTION]

An object of the present invention is to provide an air conditioner, a wind direction control method, and a program capable of reducing a vertical temperature difference of an indoor space while suppressing energy consumption.

[MEANS FOR SOLVING THE PROBLEMS]

An air conditioner of a first aspect includes: a suction temperature sensor that measures a suction temperature which is a temperature of air sucked from a suction port of an indoor unit; a radiation sensor that measures a radiation temperature which is a temperature of radiant heat from a floor surface; and a control unit. The control unit includes a floor-surface-temperature estimation unit that estimates a floor surface temperature based on the radiation temperature and a wind-direction control unit that controls a wind-direction adjustment member provided in each of a plurality of air outlets of the indoor unit. The wind-direction control unit performs a first wind-direction control. In the first wind-direction control, in a case in which a difference value between the suction temperature and the floor surface temperature exceeds a predetermined threshold value, a first state in which a wind direction of wind blown out from one air outlet is directed downward and a wind direction of the wind blown out from the remaining air outlets is directed in a direction closer to a horizontal direction and a second state in which all air outlets are directed downward are alternately repeated at predetermined intervals.
According to a second aspect, in the air conditioner of the first aspect, the wind-direction control unit sequentially switches the air outlet facing downward among the plurality of air outlets at predetermined intervals.
According to a third aspect, in the air conditioner of the first aspect, the control unit further includes a wind-volume acquisition unit that acquires information indicating a wind volume. The wind-direction control unit performs the first wind-direction control in a case in which the wind volume exceeds a predetermined wind volume. The wind-direction control unit performs a second wind-direction control. In the second wind-direction control, in a case in which the wind volume does not exceed the predetermined wind volume, the wind direction of the wind blown out from all air outlets is directed downward.
According to a fourth aspect, in the air conditioner of the first aspect, the control unit further includes a human-body-detection-result acquisition unit that acquires human body detection result information indicating whether a human is present in a room. The wind-direction control unit performs the first wind-direction control in a case in which the human is present in the room and increases a fan rotation speed of an indoor blower in a case in which the human is not present in the room.
A wind direction control method of a fifth aspect is a wind direction control method using a computer, including: a suction temperature acquiring step of acquiring information indicating a suction temperature which is a temperature of air sucked from a suction port of an indoor unit of an air conditioner installed on a ceiling; a radiation temperature acquiring step of acquiring radiation temperature information indicating a temperature of radiant heat from a floor surface; a floor surface temperature estimating step of estimating a floor surface temperature based on the radiation temperature information; and a wind direction control step of controlling a wind-direction adjustment member provided in each of a plurality of air outlets of the indoor unit and in a case in which a difference value between the suction temperature and the floor surface temperature exceeds a predetermined threshold value, alternately repeating at predetermined intervals a first state in which a wind direction of wind blown out from one air outlet is directed downward and a wind direction of the wind blown out from the remaining air outlets is directed in a direction closer to a horizontal direction and a second state in which all air outlets are directed downward.
A program of a sixth aspect causes a computer to perform: a suction temperature acquiring step of acquiring information indicating a suction temperature which is a temperature of air sucked from a suction port of an indoor unit of an air conditioner installed on a ceiling; a radiation temperature acquiring step of acquiring radiation temperature information indicating a temperature of radiant heat from a floor surface; a floor surface temperature estimating step of estimating a floor surface temperature based on the radiation temperature information; and a wind direction control step of controlling a wind-direction adjustment member provided in each of a plurality of air outlets of the indoor unit and in a case in which a difference value between the suction temperature and the floor surface temperature exceeds a predetermined threshold value, alternately repeating at predetermined intervals a first state in which a wind direction of wind blown out from one air outlet is directed downward and a wind direction of the wind blown out from the remaining air outlets is directed in a direction closer to a horizontal direction and a second state in which all air outlets are directed downward.

[BRIEF DESCRIPTION OF THE DRAWINGS]

FIG. 1 is a schematic view showing an overall configuration of an air conditioner 1 according to a first embodiment of the present invention.
FIG. 2 is a diagram showing an operation of a louver 12 of the air conditioner 1 according to the first embodiment of the present invention.
FIG. 3 is a schematic view showing a detection range of a radiation sensor 15 of the air conditioner 1 according to the first embodiment of the present invention.
FIG. 4 is a diagram showing wind direction control by the air conditioner 1 of the first embodiment.
FIG. 5 is a block diagram showing a functional configuration of a control unit 11 of the air conditioner 1 according to the first embodiment of the present invention.
FIG. 6 is a flowchart showing an operation of the air conditioner 1 according to the first embodiment of the present invention.
FIG. 7 is a diagram showing various conditions when an effectiveness verification is performed.
FIG. 8 is a diagram visually showing a measurement result of an upper temperature in a case in which full downward wind direction control is performed.
FIG. 9 is a diagram visually showing a measurement result of an upper temperature in a case in which direction-specific wind direction control is performed.
FIG. 10 is a diagram visually showing a measurement result of a lower temperature in a case in which full downward wind direction control is performed.
FIG. 11 is a diagram visually showing a measurement result of a lower temperature in a case in which direction-specific wind direction control is performed.
FIG. 12 is a block diagram showing an operation of a control unit 11a of an air conditioner 1a according to a second embodiment of the present invention.
FIG. 13 is a flowchart showing an operation of the air conditioner 1a according to the second embodiment of the present invention.
FIG. 14 is a schematic view showing an overall configuration of an air conditioner 1b according to a third embodiment of the present invention.
FIG. 15 is a block diagram showing a functional configuration of a control unit 11b of the air conditioner 1b according to the third embodiment of the present invention.
FIG. 16 is a flowchart showing an operation of the air conditioner 1b according to the third embodiment of the present invention.

[EMBODIMENTS FOR CARRYING OUT THE INVENTION]

Hereinafter, an air conditioner, a wind direction control method, and a program of the embodiment will be described with reference to the drawings.

Hereinafter, a first embodiment of the present invention will be described. FIG. 1 is a schematic view showing an overall configuration of an air conditioner 1 according to the first embodiment of the present invention. As shown in FIG. 1, the air conditioner 1 includes an indoor unit 10, an outdoor unit 20, and a refrigerant pipe 30.
The indoor unit 10 is installed, for example, on a ceiling of an office building, a residence, or the like. The indoor unit 10 is an indoor unit of an air conditioner that can blow out warm or cool wind in multiple directions. Here, as an example, the indoor unit 10 is a ceiling blow type indoor unit capable of blowing out warm or cool wind (hereinafter, collectively referred to as "wind") from four air outlets provided in four directions. Note that, in this embodiment, the wind direction control of warm wind when the indoor unit 10 performs a heating operation will be described. However, the present invention can be also applied to the wind direction control of cool wind when the indoor unit 10 performs a cooling operation.
The outdoor unit 20 is an outdoor unit of an air conditioner that is connected to the indoor unit 10 by a refrigerant pipe 30 (crossover pipe). Note that, here, as an example, the outdoor unit 20 is connected to one indoor unit 10 in a one-to-one relationship. The outdoor unit 20 may have a configuration in which a plurality of indoor units 10 are connected to one outdoor unit 20. The refrigerant pipe 30 is a pipe for circulating the refrigerant between the indoor unit 10 and the outdoor unit 20. The indoor unit 10 and the outdoor unit 20 are connected by the refrigerant pipe 30 to form a refrigeration cycle that circulates refrigerant.
The indoor unit 10 includes, for example, an indoor heat exchanger, an indoor expansion valve, and an indoor blower, all of which are not shown.
The indoor heat exchanger is, for example, a fin tube type heat exchanger. The indoor expansion valve is, for example, an electronic expansion valve (PMV). The opening degree of the indoor expansion valve can be changed (adjusted). For example, as the opening of the indoor expansion valve increases, the refrigerant becomes more likely to flow through the indoor expansion valve. On the other hand, as the opening degree of the indoor expansion valve decreases, the refrigerant becomes less likely to flow through the indoor expansion valve. Specifically, the indoor heat exchanger includes a valve body which has a through hole and a needle which can advance and retract into the through hole. In a case in which the through hole is blocked with a needle, the refrigerant will not flow to the indoor heat exchanger. At this time, the indoor heat exchanger is closed and the opening degree of the indoor heat exchanger is smallest. On the other hand, when the needle is farthest from the through hole, the refrigerant flows most easily into the indoor heat exchanger. At this time, the indoor heat exchanger is in an open state, and the opening degree of the indoor heat exchanger is largest.
The indoor heat exchanger and the indoor expansion valve are connected by the refrigerant pipe 30. Note that, the refrigerant may be, for example, R410A or R32. The refrigerant may include refrigerating machine oil or the like.
The indoor blower is, for example, a blower provided with a centrifugal fan. Note that, the fan of the indoor blower may be, for example, an axial flow fan or other fans having different structures. The fan of the indoor blower is disposed to face the indoor heat exchanger. In a case in which the fan of the indoor blower is operated, indoor air is sucked into the indoor unit 10. The air sucked into the indoor unit 10 exchanges heat with the refrigerant in the indoor heat exchanger, and is released back into the room again by the operation of the fan.
The outdoor unit 20 includes, for example, an outdoor heat exchanger, a four-way valve, a compressor, an outdoor expansion valve, an outdoor blower, and an accumulator, all of which are not shown. The refrigerant pipe 30 connects the outdoor expansion valve, the outdoor heat exchanger, the four-way valve, the compressor, and the accumulator.
The outdoor heat exchanger is, for example, a fin tube type heat exchanger. The four-way valve is a valve for switching the direction in which the refrigerant flows in the refrigerant pipe 30. The four-way valve switches the refrigerant flow direction between a direction during a heating operation and a direction during a cooling operation (or defrosting operation) opposite to that direction. However, the air conditioner 1 according to this embodiment may be an air conditioner dedicated for heating.
The compressor can change the operation frequency by known inverter control. The compressor sucks the refrigerant from a suction port and compresses the refrigerant therein. The compressor discharges the compressed refrigerant from a discharge port to the outside. An accumulator is attached to the suction port of the compressor. The accumulator separates the refrigerant into liquid refrigerant and gas refrigerant, and stores the liquid refrigerant.
The outdoor expansion valve is configured in the same manner as the indoor expansion valve. The outdoor expansion valve is, for example, a power expansion valve (PMV). The opening degree of the outdoor expansion valve can be changed (adjusted). For example, as the opening degree of the outdoor expansion valve increases, the refrigerant becomes more likely to flow through the outdoor expansion valve. On the other hand, as the opening degree of the outdoor expansion valve decreases, the refrigerant becomes less likely to flow through the outdoor expansion valve.
The outdoor blower is provided with an axial flow fan. Note that, the fan of the indoor blower may be a fan having another structure, such as a centrifugal fan. The fan of the outdoor blower is disposed to face the outdoor heat exchanger. In a case in which the fan of the outdoor blower is operated, heat exchange occurs between the outdoor air and the outdoor heat exchanger.
Furthermore, as shown in FIG. 1, the indoor unit 10 includes a control unit 11, louvers 12-1 to 12-4 respectively provided at four air outlets, a suction port 13, a remote controller 14, a radiation sensor 15, and a suction port temperature sensor 16.
The control unit 11 is an information processing device that controls the operation of the air conditioner 1. The control unit 11 is an example of a wind direction control device. The control unit 11 includes, for example, a processor such as a central processing unit (CPU), a memory, and an auxiliary storage device connected via a bus. The control unit 11 reads and executes a program from, for example, the auxiliary storage device. The auxiliary storage device is configured using a storage medium such as a magnetic hard disk device or a semiconductor storage device. For example, the auxiliary storage device is configured using a non-volatile memory such as an electrically erasable programmable read-only memory (EEPROM).
Note that, all or part of the control unit 11 may be realized using hardware such as an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA). The program may be recorded in a computer-readable recording medium. Examples of computer-readable recording media include portable media such as flexible disks, optical magnetic disks, ROMs, and CD-ROMs, and storage devices such as hard disks built into computer systems. The program may be transmitted via a telecommunications line.
The louvers 12-1 to 12-4 are provided at four air outlets provided in the indoor unit 10 to blow wind in all four directions. The louvers 12-1 to 12-4 are wind-direction adjustment members that can adjust the wind direction of wind blown out from the indoor unit 10 at least in the vertical direction. Note that, in the following description, in a case in which there is no need to distinguish between the louvers 12-1 to 12-4, they will simply be referred to as the "louver 12".
FIG. 2 is a diagram showing the operation of the louver 12 of the air conditioner 1 according to the first embodiment of the present invention. As shown in FIG. 2, the indoor unit 10 can switch the state of the louver 12 between at least the state (A) and the state (B). The state (A) is a state in which the angle of the louver 12 is set to an angle that blows wind in a direction that is relatively closer to horizontal (that is, in a direction that is nearly parallel to the floor or ceiling). On the other hand, the state (B) is a state in which the angle of the louver 12 is set to an angle that blows wind downward in a direction relatively closer to vertical (that is, in a more downward direction).
Hereinafter, the direction of the louver 12 in the state (A) may be referred to as the "horizontal direction", and the direction of the louver 12 in the state (B) may be referred to as the "downward direction". Note that, in this embodiment, the vertical wind direction that can be adjusted by the louver 12 is only two directions (only two stages) as described above. The wind direction may be adjustable in more directions (three or more stages). Note that, the angles of the louvers 12-1 to 12-4 are individually controlled by the control unit 11.
A description will be continued by returning to FIG. 1. The suction port 13 is an opening through which the indoor unit 10 sucks indoor air. The suction port 13 is provided with a suction temperature sensor 16 to be described later.
The remote controller 14 is an input interface that accepts operational inputs by a user regarding settings of the air conditioner 1. For example, the remote controller 14 accepts input operations for instructing the power state of the air conditioner 1 to be switched between on and off states. Alternatively, for example, the remote controller 14 accepts an input operation for instructing a set temperature. For example, the user operates the remote controller 14 to specify a desired temperature in the room.
The remote controller 14 outputs instruction information based on an input operation to the control unit 11 of the indoor unit 10. Note that, the remote controller 14 and the control unit 11 may be connected via a wired communication path. The remote controller 14 and the control unit 11 may be connected via a wireless communication path. The control unit 11 controls the indoor unit 10 and the outdoor unit 20 based on instruction information input from the remote controller 14. Accordingly, the air conditioner 1 can control the room temperature and the switching of the power state of the air conditioner 1 between on and off states based on instruction information input from the remote controller 14.
The radiation sensor 15 is a sensor that detects infrared rays radiated from each location on the floor surface and measures the radiant heat temperature at each location on the floor surface. Note that, the radiation sensor 15 may be configured to measure the radiant heat temperature at only one location on the floor surface.
FIG. 3 is a schematic view showing a detection range of the radiation sensor 15 of the air conditioner 1 according to the first embodiment of the present invention. As shown in FIG. 3, for example, the radiation sensor 15 is installed at one corner of the indoor unit 10. However, the installation location of the radiation sensor 15 is not limited to this embodiment. For example, the radiation sensor 15 can measure the radiant heat temperature at each location on the floor surface within the detection range d. Note that, in this embodiment, the detection range d of the radiation sensor 15 is a square. For example, the detection range d may have other shapes such as a circle. The radiation sensor 15 outputs the measurement result data to the control unit 11. The control unit 11 estimates (calculates) the temperature at each location on the floor surface within the detection range d (hereinafter, referred to as "floor surface temperature") based on the acquired measurement result data of the radiant heat temperature.
A description will be continued by returning to FIG. 1. The suction temperature sensor 16 is a sensor that measures the temperature of air sucked into the indoor unit 10 from the indoor space (hereinafter, referred to as the "suction temperature"). The suction temperature sensor 16 may be, for example, a thermistor or the like. The suction temperature sensor 16 outputs the measurement result data of the suction temperature to the control unit 11.
The control unit 11 calculates the temperature difference (vertical temperature difference) between the floor surface temperature estimated based on the data acquired from the radiation sensor 15 and the suction temperature indicated by the data acquired from the suction temperature sensor 16. The control unit 11 controls the direction (angle) of the louver 12 based on the calculated vertical temperature difference to control the wind direction. Note that, the control unit 11 may further control the fan rotation speed of the indoor blower to control the wind volume (wind speed) or control the opening degree of the indoor expansion valve to control the temperature based on the calculated vertical temperature difference. Note that, the control unit 11 may perform the above-described wind direction control or the like by further taking into consideration instruction information (setting information) acquired from the remote controller 14.
Note that, in this embodiment, the vertical temperature difference is calculated using the radiation sensor 15 and the suction temperature sensor 16 provided in the indoor unit 10. As long as the vertical temperature difference can be calculated, the present invention is not limited to the above-described configuration. For example, the floor surface temperature may be measured by a temperature sensor installed on the floor surface instead of the radiation sensor 15. Furthermore, the temperature in the upper space of the room may be measured by a temperature sensor installed at the upper part of the wall surface inside the room instead of the suction temperature sensor 16.
Generally, in a case in which heating is performed using a ceiling blow type indoor unit, the floor surface temperature (the temperature at the lower part of the room) tends to be relatively lower than the suction temperature (the temperature at the higher part of the room) due to factors such as the effect of wind buoyancy. Accordingly, occupants in the room may feel uncomfortable due to the relatively low temperature around their feet.
In contrast, in the air conditioner 1 according to this embodiment, in a case in which the temperature difference between the suction temperature and the floor surface temperature exceeds a predetermined value (that is, in a case in which the vertical temperature difference is large), all louvers 12 are not simply directed downward as in the conventional art. The air conditioner 1 according to this embodiment controls the wind direction by adjusting the direction of one louver 12 to face downward and adjusting the directions of the remaining (three other) louvers 12 to all face horizontally.
As shown in FIG. 2, in a case in which the louver 12 is directed horizontally (that is, in the state (A)), the louver 12 is angled so as to more effectively block the opening (air outlet) of the indoor unit 10. Therefore, the wind volume of wind blown out is smaller than in a case in which the louver 12 faces downward (that is, in the state (B)). Therefore, in a case in which the wind direction of only one louver 12 is directed downward, a larger wind volume of wind (higher wind speed) will be blown out intensively from the air outlet of the downward-directed louver 12 than from the other three air outlets with louvers 12 directed horizontally. Accordingly, since more wind can be sent to the lower part of the room, the vertical temperature difference of the room can be reduced.
Furthermore, since the wind blown out from the horizontally directed louver 12 also reflects off the wall surface of the room and then reflects off the floor and ceiling while circulating throughout the room, a circulation effect is generated. This circulation effect also reduces the vertical temperature difference of the indoor space.
Furthermore, the air conditioner 1 according to this embodiment does not only obtain the effect of reducing the vertical temperature difference of the indoor space. The air conditioner 1 according to this embodiment can also obtain the effects described below. The air conditioner 1 according to this embodiment performs control to switch the air outlets that orient the louvers 12 downward at regular intervals in order to reduce variations in floor surface temperature. Hereinafter, an example of the wind direction control by the air conditioner 1 according to this embodiment will be described.
FIG. 4 is a diagram showing the wind direction control by the air conditioner 1 of the first embodiment. As shown in FIG. 4, in the wind direction control by the air conditioner 1 of this embodiment, the basic state of the direction of the four louvers 12 is a first state in which all louvers 12 face downward (the state shown in the center diagram of FIG. 4).
First, in a case in which the temperature difference between the suction temperature and the floor surface temperature (the vertical temperature difference) exceeds a predetermined value, the air conditioner 1 adjusts the directions of the louvers 12-2, 12-3, and 12-4 to the horizontal direction ((1) in FIG. 4). Accordingly, the wind volume of wind blown out from the air outlet having the louver 12-1 only facing downward increases (the wind speed increases), and the wind is sent further toward the lower part of the room. After five minutes have elapsed, the air conditioner 1 returns the louvers 12-2, 12-3, and 12-4 to their basic states ((2) in FIG. 4).
Next, in a case in which the vertical temperature difference exceeds a predetermined value after five minutes have elapsed in the basic state, the air conditioner 1 adjusts the directions of the louvers 12-1, 12-3, and 12-4 to the horizontal direction ((3) in FIG. 4). Accordingly, the wind volume of wind blown out from the air outlet having the louver 12-2 only facing downward increases (the wind speed increases), and the wind is sent further toward the lower part of the room. After five minutes have elapsed, the air conditioner 1 returns the louvers 12-1, 12-3, and 12-4 to the basic state ((4) in FIG. 4).
Next, in a case in which the vertical temperature difference exceeds a predetermined value after five minutes have elapsed in the basic state, the air conditioner 1 adjusts the directions of the louvers 12-1, 12-2, and 12-4 to the horizontal direction ((5) in FIG. 4). Accordingly, the wind volume of wind blown out from the air outlet having the louver 12-3 only facing downward increases (the wind speed increases), and the wind is sent further toward the lower part of the room. After five minutes have elapsed, the air conditioner 1 returns the louvers 12-1, 12-2, and 12-4 to the basic state ((6) in FIG. 4).
Next, in a case in which the vertical temperature difference exceeds a predetermined value after five minutes have elapsed in the basic state, the air conditioner 1 adjusts the directions of the louvers 12-1, 12-2, and 12-3 to the horizontal direction ((7) in FIG. 4). Accordingly, the wind volume of wind blown out from the air outlet having the louver 12-4 only facing downward increases (the wind speed increases), and the wind is sent further toward the lower part of the room. After five minutes have elapsed, the air conditioner 1 returns the louvers 12-1, 12-2, and 12-3 to the basic state ((5) in FIG. 4). Thereafter, the air conditioner 1 continues to repeat the operation of switching the direction of the louver 12 shown in (1) to (8) of FIG. 4 while the vertical temperature difference exceeds a predetermined value.
Note that, in the following description, the wind direction control shown in FIG. 4 in which a first state in which only one louver 12 faces downward and a second state in which all louvers 12 face downward are alternately repeated at predetermined intervals and the louvers 12 facing downward are switched in order is referred to as "direction-specific wind direction control". Furthermore, in the following description, the conventional wind direction control in which all louvers 12 are directed downward is referred to as "full downward wind direction control". Note that, the conventional general wind direction control that does not perform either of these two wind direction controls is referred to as "basic wind direction control".
In a case in which full downward wind direction control is performed, the wind may not reach the floor surface easily due to the influence of buoyancy. Furthermore, in this case, the areas on the floor surface where the wind reaches and the areas where the wind does not reach tend to become fixed, which tends to cause variations in the floor surface temperature. On the other hand, when the wind volume is increased (wind speed is increased) in order to make the wind reach the floor surface, the energy consumption increases and the noise level also increases.
In contrast, the direction-specific wind direction control by the air conditioner 1 of this embodiment shown in FIG. 4 increases the wind volume of wind blown out from the air outlet having the louver 12 facing downward (increases the wind speed) by directing only the louver 12 of one air outlet downward and directing the louvers 12 of the remaining (other three) air outlets all horizontally. Accordingly, the air conditioner 1 of this embodiment can send wind to the lower part of the room while preventing an increase in energy consumption and noise and can reduce the vertical temperature difference of the indoor space. Furthermore, the vertical temperature difference of the indoor space can be further reduced by the circulation effect.
Furthermore, as shown in FIG. 4, the direction-specific wind direction control by the air conditioner 1 of this embodiment performs control of alternately repeating a first state in which only one louver 12 faces downward and a second state in which all louvers 12 face downward at predetermined intervals and sequentially switching the louvers 12 facing downward so that they rotate. The control described above is performed by a wind-direction control unit 115 described below. Accordingly, since there is an opportunity for only one louver 12 to face downward among all louvers 12, variations in floor surface temperature are also reduced.
Note that, as described above, when switching the louvers 12 facing downward, the air conditioner 1 of this embodiment first returns to the basic state and waits for a predetermined period (five minutes) to elapse. If the state in which only one louver 12 faces downward continue without once returning the louver to the basic state, there is a risk that many areas will not receive wind for a long period of time. Accordingly, there is a possibility that areas in which the floor surface temperature reversely drops will be generated. In other words, when switching the louvers 12 facing downward, it is possible to more effectively reduce the vertical temperature difference of the indoor space while reducing variations in floor surface temperature by first returning them to the basic state and waiting for a predetermined period of time to elapse.

[Configuration of control unit]

Hereinafter, a functional configuration of the control unit 11 will be described. FIG. 5 is a block diagram showing a functional configuration of the control unit 11 of the air conditioner 1 according to the first embodiment of the present invention. As shown in FIG. 5, the control unit 11 includes a radiation-temperature acquisition unit 111, a floor-surface-temperature estimation unit 112, a suction-temperature acquisition unit 113, a control-method determination unit 114, and a wind-direction control unit 115. These components are each realized by, for example, a hardware processor such as a central processing unit (CPU) executing a program (software). Some or all of these components may be realized by hardware (a circuit unit; including circuitry) such as large scale integration (LSI), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or a graphics processing unit (GPU), or may be realized by software and hardware in cooperation.
The radiation-temperature acquisition unit 111 acquires data indicating the measurement results of the radiant heat temperature at each location on the floor surface measured by the radiation sensor 15. In other words, the control unit 11 is configured to realize the function of the radiation-temperature acquisition unit 111. The radiation-temperature acquisition unit 111 outputs the acquired data to the floor-surface-temperature estimation unit 112. Note that, as described above, the radiation sensor 15 may be configured to measure the radiant heat temperature at only one location on the floor surface.
The floor-surface-temperature estimation unit 112 acquires data indicating the measurement results of the radiant heat temperature at each location on the floor surface output from the radiation-temperature acquisition unit 111. In other words, the control unit 11 is configured to realize the function of the floor-surface-temperature estimation unit 112. The floor-surface-temperature estimation unit 112 estimates (calculates) the floor surface temperature at each location based on the acquired data. Note that, any selected method can be used to estimate the floor surface temperature based on the radiant heat temperature. For example, the floor-surface-temperature estimation unit 112 may estimate the floor surface temperature to be a temperature obtained by adding +2[°C] to the radiant heat temperature. Note that, for example, the floor-surface-temperature estimation unit 112 may regard the radiant heat temperature as the floor surface temperature.
The floor-surface-temperature estimation unit 112 determines a representative floor surface temperature based on the estimated floor surface temperatures at each location, and outputs the temperature to the control-method determination unit 114. The representative floor surface temperature is used in addition to the suction temperature to calculate the vertical temperature difference. For example, the floor-surface-temperature estimation unit 112 outputs the average value of the estimated floor surface temperatures at each location to the control-method determination unit 114 as a representative floor surface temperature. Alternatively, for example, the floor-surface-temperature estimation unit 112 may output the most frequent value or the median value of the estimated floor surface temperatures at each location as a representative floor surface temperature to the control-method determination unit 114. The floor-surface-temperature estimation unit 112 may output the lowest or highest floor surface temperature among the estimated floor surface temperatures at each location to the control-method determination unit 114 as a representative floor surface temperature.
The suction-temperature acquisition unit 113 acquires data indicating the measurement result of the suction temperature measured by the suction temperature sensor 16. In other words, the control unit 11 is configured to realize the function of the suction-temperature acquisition unit 113. The suction-temperature acquisition unit 113 outputs the acquired data to the control-method determination unit 114.
The control-method determination unit 114 acquires data indicating a representative floor surface temperature output from the floor-surface-temperature estimation unit 112. In other words, the control unit 11 is configured to realize the function of the control-method determination unit 114. Furthermore, the control-method determination unit 114 acquires data indicating the suction temperature output from the suction-temperature acquisition unit 113. The control-method determination unit 114 determines a wind direction control method based on the acquired floor surface temperature and suction temperature. For example, the control-method determination unit 114 performs the direction-specific wind direction control shown in FIG. 4 described above in a case in which a difference value obtained by subtracting the floor surface temperature from the suction temperature exceeds a predetermined threshold value (for example, 5[°C]). On the other hand, for example, the control-method determination unit 114 does not perform the direction-specific wind direction control, but performs the above-described basic wind direction control, which is the wind direction control during normal times in a case in which a difference value obtained by subtracting the floor surface temperature from the suction temperature does not exceed a predetermined threshold value (for example, 5[°C]).
The wind-direction control unit 115 performs a first wind-direction control. In other words, the control unit 11 is configured to realize the function of the wind-direction control unit 115. In the first wind-direction control, in a case in which a difference value between the suction temperature and the floor surface temperature exceeds a predetermined threshold value, a first state in which a wind direction of wind blown out from one air outlet is directed downward and a wind direction of the wind blown out from the remaining air outlets is directed in a direction closer to a horizontal direction and a second state in which all air outlets are directed downward are alternately repeated at predetermined intervals.

[Operation of air conditioner]

Hereinafter, an example of an operation of the air conditioner 1 will be described. FIG. 6 is a flowchart showing an operation of the air conditioner 1 according to the first embodiment of the present invention. For example, the operation of the air conditioner 1 shown in this flowchart starts when the power to the air conditioner 1 is switched on.
The suction temperature sensor 16 measures the suction temperature, which is the temperature of air sucked from the indoor space into the indoor unit 10 (step S001). The suction temperature sensor 16 outputs the measurement result data of the suction temperature to the control unit 11. The radiation sensor 15 detects infrared rays radiated from each location on the floor surface and measures the radiant heat temperature at each location on the floor surface (step S002). The radiation sensor 15 outputs the measurement result data to the control unit 11.
The control unit 11 estimates the floor surface temperature based on the radiant heat temperature indicated by the data acquired from the suction temperature sensor 16 (step S003). The control unit 11 calculates a difference value by subtracting the estimated floor surface temperature from the measured suction temperature (step S004). In a case in which the calculated difference value exceeds a predetermined threshold value (YES in step S005), the control unit 11 performs the direction-specific wind direction control shown in FIG. 4 described above (step S006). On the other hand, in a case in which the calculated difference value does not exceed a predetermined threshold value, the control unit 11 performs the above-described basic wind direction control, which is the wind direction control during normal times (step S007).
In a case in which a predetermined time has elapsed since the start of the wind direction control in step S006 or step S007 (YES in step S008) and an instruction to end operation has not been received (NO in step S009), the air conditioner 1 returns to step S001 and repeats the above-described operations. In a case in which an instruction to end operation has been received (YES in step S009), the operation of the air conditioner 1 shown in the flowchart of FIG. 6 ends.

(Effectiveness verification)

Hereinafter, the results of the effectiveness verification of this embodiment performed under specific conditions will be summarized. As the effectiveness verification method, the upper and lower temperatures of the indoor space were measured separately during the direction-specific wind direction control shown in FIG. 4 described above and the above-described full downward wind direction control, and the measurement results were compared with each other to perform the effectiveness verification. Note that, as described above, the direction-specific wind direction control is the wind direction control in which a first state in which only one louver 12 faces downward and a second state in which all louvers 12 face downward are alternately repeated at predetermined intervals and the louvers 12 facing downward are switched in order, and the full downward wind direction control is the wind direction control in which the wind directions of all louvers 12 are fixed to face downward.
FIG. 7 shows various conditions in a case in which the effectiveness verification was performed. As shown in FIG. 7, the upper temperature was set to the temperature at a position of 1.2 [m] above the floor, and the lower temperature was set to the temperature at a position of 0.05 [m] above the floor. Then, the temperatures were measured at each location within a 4-meter square area at a position of 1.2 [m] above the floor directly below the indoor unit 10 and at a position of 0.05 [m] above the floor. FIGS. 8 to 11 are diagrams showing the results of the effectiveness verification.
FIG. 8 is a diagram visually showing the measurement results of the upper temperature (temperature at a position of 1.2 [m] above the floor) in a case in which the full downward wind direction control is performed. As shown in FIG. 8, a 4-meter square measurement area was divided into 5 × 5 areas to be 25 areas in total, and the temperature of each area was measured. Note that, the same applies to FIGS. 9 to 11 below. In FIGS. 8 to 11, darker colored areas represent higher temperatures. As shown in FIG. 8, in a case in which the full downward wind direction control is performed, it can be seen that the upper temperature is relatively higher in the center area than in the end areas and temperature variation occurs depending on the location even at the same height (1.2 [m] above the floor).
FIG. 9 is a diagram visually showing the measurement results of the upper temperature (temperature at a position of 1.2 [m] above the floor) in a case in which the direction-specific wind direction control is performed. As shown in FIG. 9, the temperature is uniformly high throughout the entire 4-meter square measurement range as can be seen by comparing the upper temperature during the direction-specific wind direction control with the upper temperature during the full downward wind direction control shown in FIG. 8 described above. In other words, it is considered that the direction-specific wind direction control of the present invention has a large circulation effect at a position of 1.2 [m] above the floor compared to the full downward wind direction control.
FIG. 10 is a diagram visually showing the measurement results of the lower temperature (temperature at a position of 0.05 [m] above the floor) in a case in which the full downward wind direction control is performed. As shown in FIG. 10, it can be seen that the lower temperature during the full downward wind direction control is relatively lower in most areas except for some areas near the center compared to the upper temperature shown in FIG. 8 described above. In other words, it is considered that the full downward wind direction control has an effect in which wind becomes less likely to reach the floor surface, the floor surface temperature becomes lower overall, and temperature variations are likely to occur.
FIG. 11 is a diagram visually showing the measurement results of the lower temperature (temperature at a position of 0.05 [m] above the floor) in a case in which the direction-specific wind direction control is performed. As shown in FIG. 11, the temperature is uniformly high throughout the entire 4-meter square measurement range as can be seen by comparing the lower temperature during the direction-specific wind direction control with the lower temperature during the full downward wind direction control shown in FIG. 10 described above. In other words, it is considered that the direction-specific wind direction control of the present invention has an effect that wind becomes likely to reach the floor surface and variations in floor surface temperature become less likely to occur compared to the full downward wind direction control.
Furthermore, in a case of comparing the upper temperature (FIG. 8) and the lower temperature (FIG. 10) during the full downward wind direction control, it can be seen that the temperature difference between the two is large. In other words, it is considered that the full downward wind direction control is not effective enough in reducing the vertical temperature difference. On the other hand, in a case of comparing the upper temperature (FIG. 9) and the lower temperature (FIG. 11) during the direction-specific wind direction control, it can be seen that the temperature difference between the two is significantly small. In other words, it is considered that the direction-specific wind direction control of the present invention has an effect that the vertical temperature difference of the indoor space is reduced and variations in floor surface temperature are reduced. Furthermore, in a case of comparing the upper temperature and the lower temperature during the full downward wind direction control and the direction-specific wind direction control, it can be seen that the temperature is high both in the upper temperature and the lower temperature when the direction-specific wind direction control is performed. That is, in a case in which the direction-specific wind direction control is performed, it is considered that the air-conditioning of the indoor space can be efficiently performed while suppressing energy consumption.

Hereinafter, a second embodiment of the present invention will be described. Generally, a certain amount or more of wind volume (wind speed) is required for the circulation effect. In particular, in a case in which the distance from the air outlet of the indoor unit to the wall surface is far and the wind volume (wind speed) is insufficient so that the wind does not reach the wall surface, the circulation effect may be significantly reduced. In contrast, although it is considered to increase the wind volume (wind speed), there is a possibility that noise may increase and consumption energy may increase in that case.
The air conditioner according to the second embodiment described below (hereinafter, referred to as "air conditioner 1a") performs different wind direction control depending on the magnitude of the set wind volume (hereinafter, referred to as "set wind volume"). Specifically, in a case in which the vertical temperature difference is large and the set wind volume exceeds a predetermined threshold value, the air conditioner 1a performs the direction-specific wind direction control shown in FIG. 4 described above, and in a case in which the set wind volume does not exceed the threshold value, the air conditioner performs the full downward wind direction control described above. With such a configuration, the air conditioner 1a according to the second embodiment performs the wind direction control suited to the set wind volume, so that the vertical temperature difference can be reduced and variations in floor surface temperature can be reduced.
Note that, since the overall configuration of the air conditioner 1a according to the second embodiment described below is the same as the overall configuration of the air conditioner 1 according to the first embodiment shown in FIG. 1 described above, the description thereof is omitted. An indoor unit of the air conditioner 1a according to the second embodiment (hereinafter, referred to as "indoor unit 10a") includes a control unit 11a instead of the control unit 11 described above.

[Configuration of control unit]

Hereinafter, a functional configuration of the control unit 11a will be described. FIG. 12 is a block diagram showing a functional configuration of the control unit 11a of the air conditioner 1a according to the second embodiment of the present invention. As shown in FIG. 12, the control unit 11a includes a radiation-temperature acquisition unit 111, a floor-surface-temperature estimation unit 112, a suction-temperature acquisition unit 113, a control-method determination unit 114a, a wind-direction control unit 115, and a wind-volume acquisition unit 116. Similar to the above-described first embodiment, these components are each realized by, for example, a hardware processor such as a central processing unit (CPU) executing a program (software).
The radiation-temperature acquisition unit 111 acquires data indicating the measurement results of the radiant heat temperature at each location on the floor surface measured by the radiation sensor 15. The radiation-temperature acquisition unit 111 outputs the acquired data to the floor-surface-temperature estimation unit 112. The floor-surface-temperature estimation unit 112 acquires data indicating the measurement results of the radiant heat temperature at each location on the floor surface output from the radiation-temperature acquisition unit 111. The floor-surface-temperature estimation unit 112 estimates (calculates) the floor surface temperature at each location based on the acquired data. The floor-surface-temperature estimation unit 112 determines a representative floor surface temperature based on the estimated floor surface temperatures at each location, and outputs the representative floor surface temperature to the control-method determination unit 114a. The suction-temperature acquisition unit 113 acquires data indicating the measurement results of the suction temperature measured by the suction temperature sensor 16. The suction-temperature acquisition unit 113 outputs the acquired data to the control-method determination unit 114a.
The wind-volume acquisition unit 116 acquires instruction information indicating the set temperature and set wind volume output from the remote controller 14. In other words, the control unit 11 is configured to realize the function of the wind-volume acquisition unit 116. The wind-volume acquisition unit 116 outputs data indicating the set temperature and set wind volume to the control-method determination unit 114a. The wind-volume acquisition unit 116 acquires information indicating a wind volume.
The control-method determination unit 114a acquires data indicating the floor surface temperature output from the floor-surface-temperature estimation unit 112. In other words, the control unit 11 is configured to realize the function of the control-method determination unit 114a. Furthermore, the control-method determination unit 114a acquires data indicating the suction temperature output from the suction-temperature acquisition unit 113. Furthermore, the control-method determination unit 114a acquires data indicating the set temperature and set wind volume output from the wind-volume acquisition unit 116. The control-method determination unit 114a determines a control method for wind direction control based on the acquired floor surface temperature, suction temperature, set temperature, and set wind volume.
For example, in a case in which a difference value obtained by subtracting the floor surface temperature from the suction temperature exceeds a predetermined threshold value (for example, 5[°C]), the control-method determination unit 114a checks whether the wind volume exceeds a predetermined threshold value. In a case in which the wind volume exceeds a predetermined threshold value, the control-method determination unit 114a performs the direction-specific wind direction control shown in FIG. 4 as in the first embodiment described above. On the other hand, in a case in which the wind volume does not exceed a predetermined threshold value, the control-method determination unit 114a performs the above-described full downward wind direction control.
Furthermore, for example, in a case in which a difference value obtained by subtracting the floor surface temperature from the suction temperature does not exceed a predetermined threshold value (for example, 5[°C]), the control-method determination unit 114a performs basic wind direction control, which is the wind direction control during normal times, as in the first embodiment described above.

[Operation of air conditioner]

Hereinafter, an example of an operation of the air conditioner 1a will be described. FIG. 13 is a flowchart showing an operation of the air conditioner 1a according to the second embodiment of the present invention. For example, the operation of the air conditioner 1a shown in this flowchart starts when the power to the air conditioner 1a is switched on.
The suction temperature sensor 16 measures the suction temperature which is the temperature of air sucked from the indoor space into the indoor unit 10 (step S101). The suction temperature sensor 16 outputs the measurement result data of the suction temperature to the control unit 11a. The radiation sensor 15 detects infrared rays radiated from each location on the floor surface and measures the radiant heat temperature at each location on the floor surface (step S102). The radiation sensor 15 outputs the measurement result data to the control unit 11a.
The control unit 11a estimates the floor surface temperature based on the radiant heat temperature indicated by the data acquired from the suction temperature sensor 16 (step S103). The control unit 11a calculates a difference value by subtracting the floor surface temperature from the suction temperature (step S104). In a case in which the calculated difference value does not exceed a predetermined threshold value (NO in step S105), the control unit 11a performs the above-described basic wind direction control, which is the wind direction control during normal times (step S106).
On the other hand, in a case in which the calculated difference value exceeds a predetermined threshold value (YES in step S105), the control unit 11a checks whether the wind volume exceeds a predetermined threshold value (step S107). In a case in which the wind volume exceeds a predetermined threshold value (YES in step S107), the control unit 11a performs the direction-specific wind direction control shown in FIG. 4 described above (step S006). In a case in which the wind volume does not exceed a predetermined threshold value (NO in step S107), the control unit 11a performs the above-described full downward wind direction control (step S108).
In a case in which a predetermined time has elapsed since the start of the wind direction control in step S106, step S108, or step S109 (YES in step S110) and an instruction to end operation has not been received (NO in step S111), the air conditioner 1 returns to step S101 and repeats the above-described operations. In a case in which an instruction to end operation has been received (YES in step S111), the operation of the air conditioner 1a shown in the flowchart of FIG. 13 ends.

Hereinafter, a third embodiment of the present invention will be described. Generally, since it is possible to set looser standards for the noise emitted by the air conditioner compared to an environment where a human is present in an environment where no human is present in an indoor space, it is also possible to set a higher fan speed for the indoor blower. An air conditioner 1b according to the third embodiment described below is configured to detect that no human is present in the indoor space and increase the fan rotation speed of the indoor blower in a case in which the difference between the suction temperature and the floor surface temperature exceeds a threshold value. Accordingly, the air conditioner 1b can reduce the vertical temperature difference of the indoor space and reduce variations in floor surface temperature in a shorter time while no human is present in the indoor space. Furthermore, the air conditioner 1b according to the third embodiment described below is configured to perform a wind blowing operation in a case in which it is detected that no human is present in the indoor space and the difference between the suction temperature and the floor surface temperature does not exceed a threshold value. Accordingly, the air conditioner 1b can suppress energy consumption while no human is present in the indoor space.
Hereinafter, a configuration of the air conditioner 1b according to the third embodiment will be described. FIG. 14 is a schematic view showing an overall configuration of the air conditioner 1b according to the third embodiment of the present invention. As shown in FIG. 14, the air conditioner 1b includes an indoor unit 10b, the outdoor unit 20, and the refrigerant pipe 30. The configuration of the air conditioner 1b according to the third embodiment is different from the configuration of the air conditioner 1 according to the first embodiment shown in FIG. 1 described above in that the indoor unit 10b is provided instead of the indoor unit 10.
As shown in FIG. 14, the indoor unit 10b includes a control unit 11b, the louvers 12-1 to 12-4 respectively provided in four air outlets, the suction port 13, the remote controller 14, the radiation sensor 15, the suction temperature sensor 16, and a human presence sensor 17. The configuration of the indoor unit 10b of the third embodiment is different from the configuration of the control unit 11 of the indoor unit 10 of the first embodiment shown in FIG. 1 described above in that the control unit 11b is provided instead of the control unit 11 and the human presence sensor 17 is further provided.
The human presence sensor 17 can detect a human present in the indoor space. The human presence sensor 17 sequentially outputs information indicating whether a human has been detected to the control unit 11b.

[Configuration of control unit]

Hereinafter, a functional configuration of the control unit 11b will be described. FIG. 15 is a block diagram showing a functional configuration of the control unit 11b of the air conditioner 1b according to a third embodiment of the present invention. As shown in FIG. 15, the control unit 11b includes the radiation-temperature acquisition unit 111, the floor-surface-temperature estimation unit 112, the suction-temperature acquisition unit 113, a control-method determination unit 114b, the wind-direction control unit 115, the wind-volume acquisition unit 116, and a human-body-detection-result acquisition unit 117. Similar to the above-described first embodiment, these components are each realized by, for example, a hardware processor such as a central processing unit (CPU) executing a program (software).
The radiation-temperature acquisition unit 111 acquires data indicating the measurement results of the radiant heat temperature at each location on the floor surface measured by the radiation sensor 15. The radiation-temperature acquisition unit 111 outputs the acquired data to the floor-surface-temperature estimation unit 112. The floor-surface-temperature estimation unit 112 acquires data indicating the measurement results of the radiant heat temperature at each location on the floor surface output from the radiation-temperature acquisition unit 111. The floor-surface-temperature estimation unit 112 estimates (calculates) the floor surface temperature at each location based on the acquired data. The floor-surface-temperature estimation unit 112 determines a representative floor surface temperature based on the estimated floor surface temperature at each location and outputs the representative floor surface temperature to the control-method determination unit 114b. The suction-temperature acquisition unit 113 acquires data indicating the measurement result of the suction temperature measured by the suction temperature sensor 16. The suction-temperature acquisition unit 113 outputs the acquired data to the control-method determination unit 114b.
The wind-volume acquisition unit 116 acquires instruction information indicating the set temperature and set wind volume output from the remote controller 14. The wind-volume acquisition unit 116 outputs data indicating the set temperature and set wind volume to the control-method determination unit 114b. The wind-volume acquisition unit 116 acquires information indicating a wind volume.
The human-body-detection-result acquisition unit 117 can sequentially detect a human present in the indoor space. In other words, the control unit 11 is configured to realize the function of the human-body-detection-result acquisition unit 117. The human-body-detection-result acquisition unit 117 outputs information indicating the human detection result to the control-method determination unit 114b. Note that, any selected method may be used for detecting a human body. For example, a human body may be detected by a thermal camera. Note that, for example, detection may be performed based on the amount of CO₂ emissions.
The control-method determination unit 114b acquires data indicating the floor surface temperature output from the floor-surface-temperature estimation unit 112. In other words, the control unit 11 is configured to realize the function of the control-method determination unit 114b. Furthermore, the control-method determination unit 114b acquires data indicating the suction temperature output from the suction-temperature acquisition unit 113. Moreover, the control-method determination unit 114b acquires data indicating the set temperature and set wind volume output from the wind-volume acquisition unit 116. Additionally, the control-method determination unit 114b acquires data indicating the human detection result output from the human-body-detection-result acquisition unit 117.
The control-method determination unit 114b determines a wind direction control method based on the suction temperature, set temperature, set wind volume, and human detection result.
In a case in which no human body is detected by the human-body-detection-result acquisition unit 117, the control-method determination unit 114b performs the same process as the control-method determination unit 114a in the second embodiment shown in FIG. 12 described above. On the other hand, in a case in which a human is detected by the human-body-detection-result acquisition unit 117, the control-method determination unit 114b performs the process described below.
For example, in a case in which a difference value obtained by subtracting the floor surface temperature from the suction temperature does not exceed a predetermined threshold value (for example, 5[°C]), the control-method determination unit 114b performs a wind blowing operation. On the other hand, for example, in a case in which a difference value obtained by subtracting the floor surface temperature from the suction temperature exceeds a predetermined threshold value (for example, 5[°C]), the control-method determination unit 114b increases the fan rotation speed of the indoor blower.

[Operation of air conditioner]

Hereinafter, an example of an operation of the air conditioner 1b will be described. FIG. 16 is a flowchart showing an operation of the air conditioner 1b according to the third embodiment of the present invention. For example, the operation of the air conditioner 1b shown in this flowchart starts when the power to the air conditioner 1b is switched on.
In a case in which the human-body-detection-result acquisition unit 117 does not detect a human body in the indoor space (NO in step S201), the air conditioning device 1b performs the same operation as the air conditioner 1a according to the second embodiment shown in the flowchart of FIG. 13 described above. On the other hand, in a case in which the human-body-detection-result acquisition unit 117 detects a human in the indoor space (YES in step S201), the air conditioner 1b performs the operations from step S202 onwards, which will be described below.
The suction temperature sensor 16 measures the suction temperature which is the temperature of air sucked from the indoor space into the indoor unit 10 (step S202). The suction temperature sensor 16 outputs the measurement result data of the suction temperature to the control unit 11b. The radiation sensor 15 detects infrared rays radiated from each location on the floor surface and measures the radiant heat temperature at each location on the floor surface (step S203). The radiation sensor 15 outputs the measurement result data to the control unit 11b.
The control unit 11b estimates the floor surface temperature based on the radiant heat temperature indicated by the data acquired from the suction temperature sensor 16 (step S204). The control unit 11b calculates a difference value obtained by subtracting the floor surface temperature from the suction temperature (step S205). In a case in which the calculated difference value does not exceed a predetermined threshold value (NO in step S206), the control unit 11b performs a wind blowing operation (step S207). On the other hand, in a case in which the calculated difference value exceeds a predetermined threshold value (YES in step S206), the control unit 11b increases the fan rotation speed of the indoor blower (step S208).
In a case in which a predetermined time has elapsed since the start of the operation control in step S207 or step S208 (YES in step S209) and an instruction to end operation has not been received (NO in step S210), the air conditioner 1b returns to step S202 and repeats the above-described operations. In a case in which an instruction to end operation has been received (YES in step S210), the operation of the air conditioner 1b shown in the flowchart of FIG. 16 ends.
With the above-described configuration, the air conditioner of each embodiment of the present invention can reduce the vertical temperature difference of the indoor space while suppressing energy consumption.
According to the above-described embodiment, the wind direction control device includes the suction-temperature acquisition unit, the radiation-temperature acquisition unit, the floor-surface-temperature estimation unit, and the wind-direction control unit. For example, the wind direction control device is the control unit 11, 11a, or 11b of the embodiment. The suction-temperature acquisition unit is the suction-temperature acquisition unit 113 of the embodiment. The radiation-temperature acquisition unit is the radiation-temperature acquisition unit 111 of the embodiment. The floor-surface-temperature estimation unit is the floor-surface-temperature estimation unit 112 of the embodiment. The wind-direction control unit is the wind-direction control unit 115 of the embodiment. The suction-temperature acquisition unit acquires information indicating the suction temperature which is the temperature of air sucked from the suction port of the indoor unit of the air conditioner installed on the ceiling. For example, the air conditioner is the air conditioner 1, 1a, or 1b according to the embodiment. The indoor unit is the indoor unit 10, 10a, or 10b of the embodiment. The suction port is the suction port 13 of the embodiment. The radiation-temperature acquisition unit acquires radiation temperature information indicating the temperature of the radiant heat from the floor surface. The floor-surface-temperature estimation unit estimates the floor surface temperature based on the radiation temperature information. The wind-direction control unit controls the wind-direction adjustment members respectively provided in the plurality of air outlets of the indoor unit, and in a case in which a difference value between the suction temperature and the floor surface temperature exceeds a predetermined threshold value, performs the first wind-direction control in which a first state in which the wind direction of the wind blown out from one air outlet is directed downward and the wind direction of the wind blown out from the remaining air outlets is directed in a direction closer to the horizontal direction and a second state in which all air outlets are directed downward are alternately repeated at predetermined intervals. For example, the wind-direction adjustment member is the louver 12 of the embodiment. The first wind-direction control is the direction-specific wind direction control of the embodiment.
Note that, in the wind direction control device, the wind-direction control unit may be configured to sequentially switch the air outlets to be directed downward among the plurality of air outlets at predetermined intervals.
Note that, the wind direction control device may further include a wind-volume acquisition unit. In this case, for example, the wind direction control device is the control unit 11a of the embodiment. The wind-volume acquisition unit is the wind-volume acquisition unit 116 of the embodiment. The wind-volume acquisition unit acquires information indicating the wind volume. In this case, the wind-direction control unit performs a first wind-direction control in a case in which the wind volume exceeds a predetermined wind volume, and performs a second wind-direction control to direct the wind direction of the wind blown out from all air outlets downward in a case in which the wind volume does not exceed a predetermined wind volume. For example, the second wind-direction control is the full downward wind direction control of the embodiment.
Note that, the wind direction control device may further include a human-body-detection-result acquisition unit. In this case, the human-body-detection-result acquisition unit acquires human body detection result information indicating whether a human is present in the room. In this case, for example, the wind direction control device is the control unit 11b of the embodiment. The human-body-detection-result acquisition unit is the human-body-detection-result acquisition unit 117 of the embodiment. In this case, the wind-direction control unit performs the first wind-direction control in a case in which a human is present in the room, and increases the fan rotation speed of the indoor blower in a case in which no human body is present in the room.
Furthermore, according to the above-described embodiments, the air conditioner includes the suction temperature sensor, the radiation sensor, and the control unit. For example, the air conditioner is the air conditioner 1, 1a, or 1b of the embodiment. The suction temperature sensor is the suction temperature sensor 16 of the embodiment. The radiation sensor is the radiation sensor 15 of the embodiment. The control unit is the control unit 11, 11a, or 11b of the embodiment. The suction temperature sensor measures the suction temperature which is the temperature of air sucked from the suction port of the indoor unit of the air conditioner. For example, the indoor unit is the indoor unit 10, 10a, or 10b of the embodiment. The suction port is the suction port 13 of the embodiment. The radiation sensor measures the radiation temperature which is the temperature of the radiant heat from the floor surface. The control unit includes the floor-surface-temperature estimation unit and the wind-direction control unit. The floor-surface-temperature estimation unit is the floor-surface-temperature estimation unit 112 of the embodiment. The wind-direction control unit is the wind-direction control unit 115 of the embodiment. The floor-surface-temperature estimation unit estimates the floor surface temperature based on the radiation temperature. The wind-direction control unit controls the wind-direction adjustment members respectively provided in the plurality of air outlets of the indoor unit, and in a case in which a difference value between the suction temperature and the floor surface temperature exceeds a predetermined threshold value, performs the first wind-direction control in which a first state in which the wind direction of the wind blown out from one air outlet is directed downward and the wind direction of the wind blown out from the remaining air outlets is directed in a direction closer to the horizontal direction and a second state in which all air outlets are directed downward are alternately repeated at predetermined intervals. For example, the wind-direction adjustment member is the louver 12 of the embodiment. The first wind-direction control is the direction-specific wind direction control in the embodiment.
A part of the air conditioner 1 according to the above-described embodiment may be realized by a computer. In this case, the function may be realized by recording a program for realizing the function on a computer-readable recording medium, reading the program recorded on the recording medium into a computer system, and executing the program. Note that, the "computer system" mentioned herein includes hardware such as the OS and peripheral devices. Moreover, the "computer-readable recording medium" refers to portable media such as flexible disks, optical magnetic disks, ROMs, and CD-ROMs, as well as storage devices such as hard disks built into computer systems. Furthermore, the "computer-readable recording medium" may also include a medium that dynamically holds a program for a short period of time, such as a communication line in a case of transmitting a program via a network such as the Internet or a communication line such as a telephone line, and a medium that holds a program for a certain period of time, such as a volatile memory inside a computer system that is a server or client in such a case. Furthermore, the above program may be for realizing a part of the above-described functions, or may be capable of realizing the above-described functions in combination with a program already recorded in a computer system, or may be realized using hardware such as a programmable logic device (PLD) or a field programmable gate array (FPGA).
While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.

[DESCRIPTION OF REFERENCE NUMERALS]

1, 1a, 1b: Air conditioner
10, 10a, 10b: Indoor unit
11, 11a, 11b: Control unit
12: Louver
13: Suction port
14: Remote controller
15: Radiation sensor
16: Suction temperature sensor
17: Human presence sensor
20: Outdoor unit
30: Refrigerant pipe
111: Radiation-temperature acquisition unit
112: Floor-surface-temperature estimation unit
113: Suction-temperature acquisition unit
114, 114a, 114b: Control-method determination unit
115: Wind-direction control unit
116: Wind-volume acquisition unit
117: Human-body-detection-result acquisition unit
d: Detection range

Claims

An air conditioner comprising:
a suction temperature sensor that measures a suction temperature which is a temperature of air sucked from a suction port of an indoor unit;

a radiation sensor that measures a radiation temperature which is a temperature of radiant heat from a floor surface; and

a control unit that includes
a floor-surface-temperature estimation unit that estimates a floor surface temperature based on the radiation temperature, and

a wind-direction control unit that controls a wind-direction adjustment member provided in each of a plurality of air outlets of the indoor unit, wherein

the wind-direction control unit performs a first wind-direction control, and wherein

in the first wind-direction control, in a case in which a difference value between the suction temperature and the floor surface temperature exceeds a predetermined threshold value, a first state in which a wind direction of wind blown out from one air outlet is directed downward and a wind direction of the wind blown out from the remaining air outlets is directed in a direction closer to a horizontal direction and a second state in which all air outlets are directed downward are alternately repeated at predetermined intervals.
The air conditioner according to claim 1, wherein
the wind-direction control unit sequentially switches the air outlet facing downward among the plurality of air outlets at predetermined intervals.
The air conditioner according to claim 1, wherein
the control unit further includes a wind-volume acquisition unit that acquires information indicating a wind volume, wherein

the wind-direction control unit performs the first wind-direction control in a case in which the wind volume exceeds a predetermined wind volume,

the wind-direction control unit performs a second wind-direction control, and

in the second wind-direction control, in a case in which the wind volume does not exceed the predetermined wind volume, the wind direction of the wind blown out from all air outlets is directed downward.
The air conditioner according to claim 1, wherein
the control unit further includes a human-body-detection-result acquisition unit that acquires human body detection result information indicating whether a human is present in a room, wherein

the wind-direction control unit performs the first wind-direction control in a case in which the human is present in the room and increases a fan rotation speed of an indoor blower in a case in which the human is not present in the room.
A wind direction control method using a computer, comprising:
a suction temperature acquiring step of acquiring information indicating a suction temperature which is a temperature of air sucked from a suction port of an indoor unit of an air conditioner installed on a ceiling;

a radiation temperature acquiring step of acquiring radiation temperature information indicating a temperature of radiant heat from a floor surface;

a floor surface temperature estimating step of estimating a floor surface temperature based on the radiation temperature information; and

a wind direction control step of
controlling a wind-direction adjustment member provided in each of a plurality of air outlets of the indoor unit and

in a case in which a difference value between the suction temperature and the floor surface temperature exceeds a predetermined threshold value, alternately repeating at predetermined intervals a first state in which a wind direction of wind blown out from one air outlet is directed downward and a wind direction of the wind blown out from the remaining air outlets is directed in a direction closer to a horizontal direction and a second state in which all air outlets are directed downward.
A program causing a computer to perform
a suction temperature acquiring step of acquiring information indicating a suction temperature which is a temperature of air sucked from a suction port of an indoor unit of an air conditioner installed on a ceiling;

a radiation temperature acquiring step of acquiring radiation temperature information indicating a temperature of radiant heat from a floor surface;

a floor surface temperature estimating step of estimating a floor surface temperature based on the radiation temperature information; and

a wind direction control step of
controlling a wind-direction adjustment member provided in each of a plurality of air outlets of the indoor unit, and

in a case in which a difference value between the suction temperature and the floor surface temperature exceeds a predetermined threshold value, alternately repeating at predetermined intervals a first state in which a wind direction of wind blown out from one air outlet is directed downward and a wind direction of the wind blown out from the remaining air outlets is directed in a direction closer to a horizontal direction and a second state in which all air outlets are directed downward.