WO2011034294A2

WO2011034294A2 - Air conditioner and method for controlling the same

Info

Publication number: WO2011034294A2
Application number: PCT/KR2010/005769
Authority: WO
Inventors: Kwa Jin Park; Sung Kwan Park; Jae Hong Kim; Jeong Young Kim; Dong Won Lee; Ill Uk Kim
Original assignee: Lg Electronics Inc.
Priority date: 2009-09-21
Filing date: 2010-08-27
Publication date: 2011-03-24
Also published as: WO2011034294A3

Abstract

The present invention relates to air conditioners having a mosquito eradicating function, and more particularly to an air conditioner having an ultrasonic generator for eradicating mosquitoes and a method for controlling the air conditioner having an ultrasonic generator, efficiently.

Description

AIR CONDITIONER AND METHOD FOR CONTROLLING THE SAME

The present invention relates to air conditioners, and more particularly to an air conditioner having an ultrasonic generator for eradicating mosquitoes and a method for controlling the air conditioner having the ultrasonic generator, efficiently.

In a broad sense, the air conditioner is a device for air conditioning room air, including all machines for cooling, heating, humidifying, dehumidifying and cleaning the room air.

In a narrow sense, the air conditioner is a machine for cooling or heating a room with a refrigerating cycle of a compressor, a condenser, an expansion device, and an evaporator. In the air conditioners, there are a separate type and a package type.

Even though the separate type air conditioner and a package type air conditioner have the same functions, the separate type air conditioner has a cooling/heating unit mounted to an indoor unit and heat discharge/cooling unit and a compressing unit mounted to an outdoor unit which are connected with refrigerant pipelines, and the package type air conditioner has a unitized cooling and the heat discharging functions and is mounted in a hole in a wall or a window, directly.

Especially, the air conditioner drops a temperature and humidity of the room air to provide comfort in summer. The summer in which the air conditioner cools the room is a season when different kinds of noxious insects (flies, mosquitoes, mites, and so on) breed. A method is on demand, for adding an insecticide function to the air conditioner which cools the room in the summer.

Particularly, since the noxious insects, such as mosquitoes, transmit communicable diseases, necessity for the insecticide function is greater.

Accordingly, the present invention is directed to an air conditioner having an ultrasonic generator for eradicating mosquitoes and a method for controlling the air conditioner having an ultrasonic generator, efficiently.

An object of the present invention is to provide an air conditioner and a method for controlling the same, which can vary a frequency of an ultrasonic wave from an ultrasonic generator provided thereto for eradicating mosquitoes within a particular frequency band for making a lifetime of the ultrasonic generator longer and diversifying objects of insects to be eradicated.

Another object of the present invention is to provide an air conditioner and a method for controlling the same, which can avoid interference of a frequency of an ultrasonic wave from an ultrasonic generator provided thereto for eradicating mosquitoes with a frequency of a remote controller.

Still another object of the present invention is to provide an air conditioner and a method for controlling the same, which can select a frequency of an ultrasonic wave from an ultrasonic generator provided thereto for eradicating mosquitoes as a resonant frequency for maximizing a performance of the ultrasonic generator.

Additional advantages, objects, and features of the disclosure will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, an air conditioner includes an indoor unit for air conditioning indoor air, an ultrasonic generator including an ultrasonic speaker to emit an ultrasonic wave having a frequency varying within a preset frequency range, for emitting ultrasonic waves having a plurality of preset frequencies for preset time periods in a preset order respectively, the ultrasonic generator connected to the indoor unit with or without wire, and an indoor unit control unit for controlling the indoor unit and the ultrasonic generator, wherein the preset order is an order of increasing and decreasing the frequency of the ultrasonic wave, repeatedly.

In this instance, the preset frequency range can be 20 kHz or more and 100 kHz or less.

And, the plurality of preset frequencies can be greater than the frequencies included to the preset order in number.

The preset time periods may be 5 minutes or longer and 20 minutes or shorter.

The ultrasonic generator includes an ultrasonic generator control unit for controlling emission of the ultrasonic wave, and a signal amplifying unit for amplifying an input signal to the ultrasonic speaker, wherein the ultrasonic generator control unit can control the ultrasonic speaker according to the control signal from the indoor unit control unit.

In this instance, the frequencies of the ultrasonic waves included to the preset order can be at least four frequencies, and stored in the ultrasonic generator control unit.

The preset order or the preset time periods are at least two in number, and stored in the ultrasonic generator control unit.

In the meantime, the frequency of the ultrasonic wave from the ultrasonic generator can vary within a range excluding a range of an infrared remote controller frequency.

The range of an infrared remote controller frequency may be 34 kHz or more and 42 kHz or less.

At least one of the plurality of preset frequencies can be lower than the range of an infrared remote controller frequency.

The frequency of the ultrasonic generator emitted initially upon putting the ultrasonic generator into operation is lower than the range of an infrared remote controller frequency.

In the meantime, at least one of the plurality of frequencies from the ultrasonic generator can be a frequency in the vicinity of a resonant frequency of the ultrasonic speaker.

In this case, the resonant frequency of the ultrasonic speaker can be two or more than two in number.

The plurality of resonant frequencies of the ultrasonic speaker can be fixed from test values of impedance output signals from the ultrasonic speaker on pulse form input signals of which frequency varies.

In another aspect of the present invention, a method for controlling an air conditioner having a ultrasonic generator includes the steps of a control signal generating step for generating a control signal for an ultrasonic generator to emit ultrasonic waves respectively having a plurality of preset frequencies for preset time periods in a preset order according to an user input, preset settings and preset conditions, and an ultrasonic wave emitting step for emitting the ultrasonic waves according to the control signal generated in the control signal generating step, wherein the preset order is an order of increasing and decreasing the frequency of the ultrasonic wave, repeatedly.

The control signal generating step includes the step of generating the control signal to emit the ultrasonic wave of the lowest frequency of the frequencies included to the preset order, initially.

The control signal generating step further includes the step of generating the control signal to vary the plurality of preset frequencies every time the ultrasonic generator is put into operation.

The control signal generating step further includes the step of generating the control signal to change the preset order in a case the ultrasonic wave is emitted continuously after the ultrasonic wave is generated according to the preset order.

The control signal generating step further includes the step of generating the control signal to fix a range of the plurality of preset frequencies excluding an infrared remote control unit frequency range.

The control signal generating step further includes the step of generating the control signal to make at least one of the plurality of preset frequencies be in the vicinity of a resonant frequency of the ultrasonic speaker.

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

The air conditioner and the method for controlling the same of the present invention have the following advantages.

The repetitive increase and decrease of the frequency of the ultrasonic wave from the ultrasonic generator permits to increase a lifetime of the ultrasonic speaker of the ultrasonic generator.

The emission of ultrasonic waves respectively having a variety of noxious inset evasive frequencies permits to diversify objects of eradication of the insects.

The interference between the frequency of the ultrasonic wave from the ultrasonic generator provided for providing the mosquito eradicating function with the remote controller frequency can be avoided, thereby preventing domestic appliance from malfunctioning.

Furthermore, by selecting a resonant frequency as the frequency of the ultrasonic wave from the ultrasonic generator, a performance of the ultrasonic generator can be maximized.

FIG. 1 illustrates a perspective view of an air conditioner in accordance with a preferred embodiment of the present invention.

FIG. 2 illustrates an exploded perspective view of an indoor unit of an air conditioner in accordance with a preferred embodiment of the present invention.

FIG. 3 illustrates a block diagram of an air conditioner in accordance with a preferred embodiment of the present invention.

FIGS. 4A and 4B illustrate graphs showing a frequency of an input signal to an ultrasonic speaker of an ultrasonic generator in accordance with a preferred embodiment of the present invention versus impedance and a time versus a frequency of the ultrasonic speaker, respectively.

FIG. 5 illustrates a graph showing another example of a time versus a frequency of an ultrasonic wave from an ultrasonic generator mounted to an air conditioner in accordance with a preferred embodiment of the present invention.

FIGS. 6A and 6B illustrate graphs showing a frequency of an input signal to an ultrasonic speaker of an ultrasonic generator in accordance with another preferred embodiment of the present invention versus impedance and a time versus a frequency of the ultrasonic speaker, respectively.

FIGS. 7A and 7B illustrate graphs showing another example of a frequency of an input signal to an ultrasonic speaker of an ultrasonic generator versus impedance and a time versus a frequency of the ultrasonic speaker, respectively.

Reference will now be made in detail to the specific embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.

FIG. 1 illustrates a perspective view of an air conditioner 500 in accordance with a preferred embodiment of the present invention, including an indoor unit 200 for air conditioning a room, and an outdoor unit 300 connected to the indoor unit with a refrigerant pipeline 400.

As described before, in a broad sense, it is required that the air conditioner 500 is understood as a machine for air conditioning room air in a concept including a steps of room cooling, room heating, and humidifying, dehumidifying or cleaning the room air. Therefore, it is required to understand that the following description is not limit to a separate type air conditioner 500.

FIG. 1 illustrates an air conditioner 500 for cooling or heating a room, having an indoor unit 200 and an outdoor unit 300 separated from each other, wherein the indoor unit 200 is a wall mounting type.

The air conditioner 500 in FIG. 1 has an indoor heat exchanger and an outdoor heat exchanger provided to the indoor unit 200 and the outdoor unit 300, respectively. The air conditioner 500 cools or heats the room by a method in which, in a case the room is cooled, the indoor heat exchanger of the indoor unit 200 evaporates the refrigerant and the outdoor heat exchanger of the outdoor unit condenses the refrigerant, and in a case the room is heated, the outdoor heat exchanger of the outdoor unit evaporates the refrigerant and the indoor heat exchanger of the indoor unit condenses the refrigerant.

Accordingly, the indoor unit 200 and the outdoor unit 300 have fans for blowing air in processes of heat exchange of the room air and outdoor air with the heat exchangers, respectively. Therefore, in a process the refrigerant is evaporated or condensed at the indoor heat exchanger, the air blown toward the indoor heat exchanger heat exchanges with the indoor heat exchanger so as to be cooled or heated, and is supplied to the room for cooling or heating the room.

Moreover, in order to produce an insecticide function, the air conditioner 500 includes an ultrasonic generator 100. The ultrasonic generator 100 is mounted to the indoor unit 200 for emitting an ultrasonic wave to a room space having the indoor unit 200 installed therein.

The ultrasonic generator 100 may be mounted to the indoor unit 200 to be exposed, always or selectively.

Referring to FIG. 1, since the indoor unit 200 of the air conditioner 500 is in general fixedly secured to one place, such as mounted to a wall as a wall mounting type, a remote controller r may be used for controlling the air conditioner 500. The remote controller for a general domestic appliance emits a control signal of a infrared ray in controlling the domestic appliance.

Since the control signal from the remote controller r can interfere with the ultrasonic wave from the ultrasonic generator 100, in order to prevent the domestic appliance from malfunctioning and to produce the insecticide function of the ultrasonic generator 100, a scheme is required for resolving interference which is liable to take place between the ultrasonic wave from the ultrasonic generator 100 and the infrared wave from the remote controller, which will be describe, later.

The ultrasonic generator 100 may, or may not be put into operation at the same time with the fan 200 for producing the insecticide function.

FIG. 2 illustrates an exploded perspective view of the indoor unit 200 of an air conditioner in accordance with a preferred embodiment of the present invention.

The indoor unit 200 is an air conditioning unit having an air inlet 4 for drawing the room air and an air outlet 6 for discharging the air conditioned air for drawing the air through the air inlet 4 and discharging the air conditioned air through the air outlet 6. The air conditioner 500 may be of a stand type, a ceiling mounting type, or the wall mounting type. The indoor unit will be described taking the wall mounting type, as an example.

The indoor unit 200 includes a sash 10, a front frame 20, an inlet grill 21, a front panel 28, and an outlet unit 30.

The indoor unit 200 may have the air inlet 4 formed in a front and a top of the indoor unit 200, and the air outlet 6 formed in a bottom of the indoor unit 200, or an air inlet passage to be formed between the front of the indoor unit 200 and the front panel 28 as the front panel 28 is moved upward or rotated round an upper side or a lower side thereof, or the air inlet 4 formed in the top side of the indoor unit 200, the air outlet 6 formed in the bottom of the indoor unit 200, and the front panel 28 formed to cover the front of the indoor unit 200. Hereafter, the indoor unit 200 will be described, which has the air inlet 4 formed in an upper side of the indoor unit 200, specifically, in the top side of the indoor unit 200, the air outlet 6 formed in a lower side, specifically, in the bottom side of the indoor unit 200, and the front panel 28 connected to the indoor unit 200 to form an front exterior of the indoor unit 200 and to be rotated forwardly upward round a top side thereof for servicing an inside of the indoor unit 200.

The sash 10 is a case mounted to the wall having an air flow passage for passing of the air and mounting of different components therein.

The front frame 20 is arranged in front of the sash 10 to form a space between the front frame 20 and the sash 10.

The front frame 20 has

openings

4 and 5 in the top side and the front side respectively, wherein the top side opening serves as the air inlet 4 and the front side opening 5 serves as a service hole for mounting/dismounting of a filer or to be used in service of the indoor unit 200, to be described later.

The inlet grill 21, enabling the room air to be drawn into the indoor unit 200 and protect an underside thereof, is formed in a grill shape in the air inlet 4 which is the top side opening of the front frame 20.

There is an outlet unit 30 in the indoor unit 200 for guiding discharge of the conditioned air fastened to at least one of the sash 10 and the front frame 20 with fastening means, such as a fastening member, or a hooking means, such as a hook.

The sash 10 has an air flow guide 12 for guiding the air drawn through the air inlet 4 toward the air outlet 6, and an electric machinery room 13 on either side of the air flow guide 12.

The air flow guide 12 in the sash 10 for forming a flow passage of the fan 54 to be described later, includes left and right guides 15 and 16 projected forward from the sash 10, and a center guide 17 between the left and right guides 15 and 16. Either one of the left and right guides 15 and 16 has a heat exchange supporter 18 mounted thereto for supporting the indoor heat exchanger 60 and forming an air flow passage.

The electric machinery room 13 in the sash 10 has a motor mounting portion 14 mounted thereto and projected forward therefrom for seating and supporting a fan motor 52 be described later thereto.

The electric machinery room 13 has a control box 70 mounted thereto, having an indoor unit control unit 72 for controlling a fan motor 52 of the fan unit 50 described later, a wind direction controller driving unit 35 of a wind direction controller, and an ultrasonic generator controller for controlling the ultrasonic generator 100 mounted thereto. The ultrasonic generator controller will be described in detail, later.

The front frame 20 forms the air flow passage together with the sash 10 and protects the electric machinery room 13 on the sash 10.

The front frame 20 has the front opening 5 formed in a front/rear direction in front of the flow guide 12 of the sash 10 and the top side opening 4 formed in front of the top side of the flow guide 12 of the sash 10 in an up/down direction.

The outlet unit 30 has a drain portion 32 on a top side thereof for receiving condensed water dropped from the indoor heat exchanger 60 to have a drain connection hose 33 connected thereto for guiding the condensed water to an outside of the indoor unit 200. Under the drain portion 32, there is the air outlet 6 opened therein.

The outlet unit 30 has a wind direction controller for controlling a direction of wind of the air passing through the air outlet 6.

The wind direction controller includes a wind direction control unit 34 rotatably mounted to the indoor unit, more specifically, to the outlet unit 30 for controlling a wind direction of the air while guiding pass through of the air through the air outlet 6, and a wind direction control driving unit 35 for rotating the wind direction control unit 34.

The wind direction control unit 34 includes a left/right wind direction control unit for controlling a left/right wind direction of the air passing through the air outlet 6, and an up/down wind direction control unit for controlling an up/down wind direction of the air passing through the air outlet 6.

The wind direction control driving unit 35 may be connected to the left/right wind direction control unit for rotating the left/right wind direction control unit round a vertical axis, or connected to the up/down wind direction control unit for rotating up/down wind direction control unit round a horizontal axis.

The wind direction control driving unit 35 is a wind direction control motor mounted to a left side or a right side of the outlet unit 30.

In the meantime, the air conditioner of the embodiment includes the fan unit 50 for drawing the air through the air inlet 4 and discharging through the air outlet 6 via an inside of the indoor unit 200, and the indoor heat exchanger 60 for making the air drawn into the inside of the indoor unit 200 to heat exchange with the refrigerant.

The fan unit 50 includes a fan motor 52 seated on the motor mounting portion 14 in the sash 10, specifically, at the electric machinery room 14, a fan 54 mounted on a rotation shaft of the fan motor 52 and positioned at the flow guide 12, and a motor cover 56 mounted to the sash 10 to cover the fan motor 52.

The fan 54 is a cross flow fan extended in left/right directions between the flow guides 15, 16 and 17, more specifically, the left/right flow guides 15 and 16.

The indoor heat exchanger 60 is arranged in a space of the indoor unit 200 so as to be positioned between the air inlet 4 and the fan 54, specifically, in rear of the front of the front frame 20, with a bottom thereof to be positioned over the drain portion 32.

The indoor heat exchanger 60 includes a vertical portion 62 positioned vertically over the drain portion 32, a forward tilted portion 64 over the vertical portion 62 tilted upwardly backward, and a rear tilted portion 66 over the front tilted portion 64 tilted backward downwardly.

The air conditioner of the embodiment includes a filter 80 in the indoor unit 200 for cleaning the air drawn into the air inlet 4, and a filter frame 90 having the filter 80 mounted thereto.

The filter frame 90 is mounted between the air inlet 4 and the indoor heat exchanger 60 and has an opening 91 for passing through of the air and mounting the filter 80 thereto.

The ultrasonic generator 100 for eradicating or inducing noxious insects, such as mosquitoes, from the room under air conditioning with the air conditioner, may be mounted to the indoor unit 200.

Of course, the ultrasonic generator 100 may be mounted to the outdoor unit 300 for eradicating noxious insects from a space the outdoor unit 300 is installed therein.

The ultrasonic generator 100 will be described in detail with reference to FIG. 3, later.

The ultrasonic generator 100 has an ultrasonic speaker 102 for emitting an ultrasonic wave of a particular wave band that the noxious insects, such as mosquitoes, evade.

Moreover, as described later, the ultrasonic generator 100 includes a ultrasonic generator control unit 180 for receiving a control signal from the indoor unit control unit 72 and being in charge of general control of the ultrasonic generator 100, a signal generating unit 183 for generating a pulse form of input signal selectively under the control of the ultrasonic generator control unit 180, a signal amplifying unit 185 for amplifying the ultrasonic signal from the signal generating unit 183, and the ultrasonic speaker 102 for converting and forwarding the input signal amplified at the signal amplifying unit 185 into a ultrasonic wave and forwarding the ultrasonic wave, additionally.

The ultrasonic speaker 102 of the ultrasonic generator 100 may be a speaker which converts an electric signal to an acoustic signal and forwarding the acoustic signal, and may, or may not, be fixedly mounted to the indoor unit 200.

Referring to FIG. 3, the air conditioner 500 includes the indoor unit 200 having the ultrasonic generator 100 provided thereto.

The indoor unit 200 includes the fan unit 50 driven by the fan motor 52, the wind direction control unit 34 driven by the wind direction control motor 35, the indoor heat exchanger 60 for making the air drawn thus to heat exchange with the refrigerant, an indoor unit control unit 72 for controlling general operation of the indoor unit, an input unit 220 for receiving different operation orders from a user, and a display unit 230 for displaying an acoustic signal emission state, additionally.

The indoor unit control unit 72 controls general operation of the indoor unit. For an example, upon reception of an operation signal of the air conditioner from the input unit 220, such as the remote controller, the indoor unit control unit 72 controls to start operation of the air conditioner, accordingly.

In this instance, in order to make communication with a outdoor unit control unit in the outdoor unit 300, the compressor (not shown) of the outdoor unit 300 is made to operate.

The indoor unit control unit 72 controls the fan motor 52 to operate the fan unit 50 of the indoor unit following operation of the compressor (not shown) of the outdoor unit 300, and controls the wind direction control motor 35 to open the wind direction control unit 34. According to this, the air drawn from the room thus heat exchanges at the indoor heat exchanger 60, and the air heat exchanged thus is discharged to the room, again.

In the meantime, the indoor unit control unit 72 transmits an ultrasonic generator 100 operation signal to the ultrasonic generator control unit 180 of the ultrasonic generator 100. The operation signal transmits the ultrasonic generator 100 operation signal to the ultrasonic generator control unit 180, if a control signal or the ultrasonic generator 100 operation signal is received at the input unit 220.

That is, if the indoor unit is in an operation mode, the ultrasonic generator 100 may activate the insecticide function together with the room cooling/heating function, or can emit the ultrasonic wave separately without operating the indoor unit for activating the insecticide function only.

It is preferable that the ultrasonic generator 100 has a frequency in a range of 20 kHz ~ 100 kHz as a frequency band of the ultrasonic wave that the noxious insects evade. Since frequencies flies, mosquitoes, mites, moths, and Mayflies evade are different from one another respectively, the frequency of the ultrasonic wave from the ultrasonic generator 100 of the present invention varies, detailed description of which will be made, later.

Upon reception of the operation signal from the ultrasonic generator control unit 180, the signal generating unit 183 emits a pulse signal according to the ultrasonic wave. The signal generating unit 183 can perform pulse width modulation PWM for varying the evasive frequency of the pulse signal. According to this, the frequency of the pulse signal can be varied, simply.

The signal amplifying unit 185 amplifies the pulse signal from the signal generating unit 183. The signal amplifying unit 185 may be fabricated of an OP amp, transistor.

The ultrasonic speaker 102 converts the pulse signal amplified thus to the ultrasonic wave. In the meantime, the ultrasonic speaker 102 may emit ultrasonic waves of different frequencies in succession. The ultrasonic speaker 102, a speaker, may be provided with a piezoelectric element as means for generating the ultrasonic wave.

The ultrasonic generator control unit 180, the signal generating unit 183, and the signal amplifying unit 185 may be arranged mounted to a board the same with the indoor unit control unit 72, or may be mounted to separate board which is detachably mounted together with the indoor unit control unit 72.

The ultrasonic speaker 102 may be connected to the signal amplifying unit 185 with wiring, or may be configured detachably with the signal amplifying unit 185.

The wiring may include a pulse signal transmission wiring for transmission of the amplified signal from the signal amplifying unit 185 to the ultrasonic speaker 102, and a power source wiring for supplying power to the ultrasonic speaker 102.

As described before, the ultrasonic generator control unit 180, the signal generating unit 183 and the signal amplifying unit 185 may be arranged on the control box 70 together with the board having the indoor unit control unit 72 mounted thereto, side by side.

In the meantime, if an acoustic signal is emitted from the ultrasonic generator 100, the indoor unit control unit 72 may control the display unit 230 to display the acoustic signal. Since the acoustic signal from the ultrasonic generator 100 can be, not in an audible band, but in a frequency band of 20 kHz ~ 100 kHz, in order to make the user to perceive an operation of the ultrasonic generator 100 intuitively, it is preferable that emission of the acoustic signal is displayed on the display unit 230.

Or, it may be possible to indicate the frequency of the ultrasonic wave from the ultrasonic generator 100 in numerals.

The display unit 230 may be fabricated by providing light emitting diodes which emit a light. If the acoustic signal is emitted from the ultrasonic generator 100, the display unit 230 can indicate the acoustic signal in a variety of fashions.

For an example, the display unit 230 can indicate such that a number of light emissions per unit time period or a light emission quantity becomes the greater as a frequency band of the acoustic signal becomes the greater. According to this, the user can guess not only emission of the acoustic signal, but also an approximate frequency of the acoustic signal, intuitively.

In the meantime, it is also possible that, if a level of the pulse signal from the signal amplifying unit 185 detected exceeds a preset value, determining that an abnormal operation takes place, the operation of the ultrasonic generator control unit 180 is stopped.

FIGS. 4A and 4B illustrate graphs showing a frequency of an input signal to an ultrasonic speaker 102 of the ultrasonic generator 100 in accordance with a preferred embodiment of the present invention versus impedance and a time versus a frequency of the ultrasonic speaker 102, respectively.

The ultrasonic generator 100 generates ultrasonic waves respectively having a plurality of preset frequencies for preset time periods in a preset order.

The plurality of preset frequencies may vary every time the ultrasonic generator 100 is operated. And, the plurality of preset frequencies may be greater than the frequencies included to the preset order in number.

This is for emitting a variety of noxious insect evasive frequencies to diversify kinds of the noxious insects the ultrasonic generator 100 can eradicate.

Alikely, if the ultrasonic waves are emitted in succession after the ultrasonic waves are emitted according to the preset order, the preset order may be kept varied.

And, the preset time periods may be at least two, and can be stored in the ultrasonic generator control unit 180. As described before, the ultrasonic generator 100 includes the ultrasonic generator control unit 180 for controlling emission of the ultrasonic wave, and the signal amplifying unit 185 for amplifying the input signal to the ultrasonic speaker 102, and the preset order may be at least two and can be stored in the ultrasonic generator control unit 180. The ultrasonic generator 100 will be described with reference to FIGS. 4A and 4B.

In detail, FIG. 4A illustrates a graph showing a frequency of a particular input signal to an ultrasonic speaker of the ultrasonic generator 100 versus impedance and FIG. 4B illustrates a graph showing a time versus a frequency of the ultrasonic wave from the ultrasonic speaker 102.

The impedance is an intrinsic value of a circuit indicating a degree of difficulty of a current flow through a circuit. Therefore, the impedance of the input signal to the ultrasonic speaker 102 may vary with a material and so on of the ultrasonic speaker 102.

And, the impedance may vary with the frequencies of the input signals even for the same ultrasonic speaker 102. FIG. 4A illustrates a graph showing variation of the impedance measured while the frequency of a particular input signal to an ultrasonic speaker 102 is increased, slowly.

A transverse axis denotes the variation of the frequency kHz of the input signal and a longitudinal axis denotes the impedance Ω of the ultrasonic speaker 102.

As described before, the air conditioner 100 of the present invention has the ultrasonic generator 100 for eradicating noxious insects, such as mosquitoes. The ultrasonic generator 100 emits a frequency in a range of about 20 kHz to 100 kHz for eradicating the noxious insects, such as the mosquitoes.

Referring to FIG. 1, since the indoor unit 200 of the air conditioner can be mounted on the wall, the remote controller r may be used for controlling the air conditioner.

The remote controller of a general domestic appliance uses a frequency in the vicinity of 38kHz mostly in emitting a control signal for the domestic appliance.

According to this, there is a problem caused by a fact that the infrared frequency emitted from the remote controllers of various domestic appliances are the same with the ultrasonic frequency emitted from the ultrasonic generator 100 at the air conditioner for eradicating the mosquitoes and so on.

That is, there can be interference caused between the ultrasonic wave and the infrared ray of which frequencies are the same. If the control signals of the ultrasonic wave and the infrared ray interfere, the infrared ray control signal can disappear by destructive interference, or amplitude of the wave can increase by constructive interference, failing to transmit the control signal, properly.

Such interference makes control of a target domestic appliance with the infrared control signal from the remote controller impossible.

Therefore, it is preferable that the frequency of the ultrasonic wave from the ultrasonic generator 100 avoids a particular frequency band for preventing the frequency of the ultrasonic wave from interfering with the frequency of the infrared ray from the remote controller r.

In this instance, the particular frequency band can be 34 kHz to 42 kHz. It can be interpreted that the 34 kHz to 42 kHz can be a band including the frequency of a general remote controller of an infrared ray. If a remote controller of a infrared ray which uses a frequency outside of above band can be used, the frequency of the ultrasonic speaker can be fixed with a band which avoids above band.

And, according to an insecticide performance test of the ultrasonic generator 100, the frequency of the ultrasonic wave having the insecticide function varies with kinds of the noxious insects. Moreover, it is verified that a frequency at which the insecticide function is active can vary even to the same kind of the noxious insect.

That is, since the evasive frequency can vary with kinds of the noxious insects, it is necessary to vary the frequency of the ultrasonic speaker for dealing with the various kinds of noxious insects.

Accordingly, in emission of the ultrasonic wave having the insecticide function, it is preferable that the frequency of the ultrasonic wave is varied.

FIGS. 4A and 4B illustrate graphs showing a frequency of an input signal to the ultrasonic speaker of the ultrasonic generator 100 in accordance with a preferred embodiment of the present invention versus impedance and a time versus a frequency of the ultrasonic speaker 102, respectively.

The ultrasonic generator 100 emits the ultrasonic waves of the plurality of preset frequencies for the preset time periods in the preset order.

The plurality of preset frequencies, the preset time periods and the preset order may be stored in the ultrasonic generator control unit 180, and the plurality of preset frequencies can be greater than the frequencies included to the preset order in number.

Moreover, the preset time periods are at least two, and if the ultrasonic wave is emitted in succession after emission of the ultrasonic wave according to the preset order, the preset order may not be the same.

As illustrated in the graph showing a frequency of a particular input signal to an ultrasonic speaker 102 versus impedance in FIG. 4A, the impedance and the frequency of the input signal to the ultrasonic speaker are inversely proportional, substantially.

Referring to FIG. 4A, the ultrasonic wave from the ultrasonic speaker 102 has a frequency which avoids an infrared frequency band IR of the wave from the remote controller of the infrared type.

Since the infrared frequency band IR is in the range of 38 kHz, the frequency band of the ultrasonic wave from the ultrasonic generator 100 may fall on a range of 20 kHz to 100 KHz from which the frequency band of the infrared frequency IR, i.e., 34 kHz to 42 kHz, is avoided.

And, the ultrasonic waves from the ultrasonic speaker have frequencies varied with the preset time periods, respectively.

Referring to FIGS. 4A and 4b, the ultrasonic speaker emits ultrasonic waves having a first frequency ①, a second frequency ②, a third frequency ③, a fourth frequency ④, a fifth frequency ⑤, and a sixth frequency ⑥ for the preset time periods, respectively.

For an example, a preset time period in which the ultrasonic wave having the frequency is kept emitting may be over 5 minutes and below 20 minutes. If the preset time period is set to be around 12 minutes as a test, an intended insecticide effect is obtainable and overload on the ultrasonic speaker can also be avoided.

In this instance, of the plurality of frequencies of the ultrasonic waves from the ultrasonic generator 100 (for an example, the first frequency ①, the second frequency ②, the third frequency ③, the fourth frequency ④, the fifth frequency ⑤, and the sixth frequency ⑥), at least one frequency can be lower than the frequency of the infrared remote controller.

As shown in FIG. 4A, the first frequency ① has a frequency lower than the infrared frequency IR.

And, as shown in FIGS. 4A and 4B, the ultrasonic generator 100 may be configured to emit the ultrasonic wave having a frequency lower than the frequency of the infrared remote controller. Since a power and an intensity of the frequency of the ultrasonic wave from the ultrasonic generator 100 can be related to a load on the ultrasonic speaker 102, in order to minimize an initial operation load on the ultrasonic speaker 102, it is necessary that the ultrasonic generator 100 is configured to emit an ultrasonic wave having a frequency lower than the frequency of the infrared remote controller at a first time.

As shown in FIGS. 4A and 4B, though the frequency from the ultrasonic generator 100 is higher than 20kHz, by emitting the ultrasonic wave at the first frequency ① which is the lowest of the first frequency ①, the second frequency ②, the third frequency ③, the fourth frequency ④, the fifth frequency ⑤, and the sixth frequency ⑥, the initial load on the ultrasonic generator 100 can be reduced.

And, though the frequency of the ultrasonic wave from the ultrasonic speaker 102 of the ultrasonic generator 100 is maintained at the particular frequency for the preset time period, the frequency of the ultrasonic wave from the ultrasonic speaker 102 increases and decreases for preset time periods, repeatedly.

That is, the ultrasonic speaker 102 can emit the ultrasonic waves for the preset time periods in the preset order (on the assumption that the increase and the decrease are repeated).

And, the frequencies included to the preset order can be at least four for emitting the ultrasonic wave of various evasive frequencies.

If the frequency of the ultrasonic wave changes in a direction of constant increase, it results in an overload on the ultrasonic speaker 102 to make a lifetime of the ultrasonic speaker 102 shorter. Even in a case the ultrasonic speaker 102 keeps emitting the ultrasonic wave of the same frequency, the case has a problem in that various kinds of the noxious insects can not be eradicated along with the problem of the short lifetime. Therefore, the frequency of the ultrasonic wave emitted from the ultrasonic generator 100 mounted to the air conditioner of the present invention for emitting the ultrasonic wave varies in a pattern in which the frequency increases and decreases for fixed time periods, repeatedly.

It is preferable that the increase and decrease of the frequency of the ultrasonic wave from the ultrasonic generator is repeated two or more than two times. Of course, if the time period in which the ultrasonic wave having the particular frequency is emitted becomes longer, the increase and decrease of the frequency of the ultrasonic wave may be repeated less than two times.

FIG. 4B illustrates a graph showing a time versus a frequency of the ultrasonic wave from the ultrasonic speaker 102.

The first frequency ①, the second frequency ②, the third frequency ③, the fourth frequency ④, the fifth frequency ⑤, and the sixth frequency ⑥ are the higher in an order of 20 kHz <the first frequency ① <the infrared frequency IR < the fifth frequency ⑤ < the third frequency ③ < the sixth frequency ⑥ < the fourth frequency ④ < the second frequency ② < 100 kHz.

In this instance, at least one of the plurality of the frequencies may be lower than the frequency of the infrared remote controller. In FIG. 4B, the first frequency ① is shown lower than the infrared remote controller frequency.

The ultrasonic generator 100 may have an ultrasonic frequency lower than the infrared remote controller frequency IR set thereto to emit at first, for reducing an initial load on the ultrasonic speaker 102 of the ultrasonic generator 100 at the time the ultrasonic speaker 102 is put into initially.

Referring to FIGS. 4A and 4B, the ultrasonic wave may be emitted by a method in which an ultrasonic wave having the first frequency ① is emitted for a first time period △t1, an ultrasonic wave having the second frequency ② higher than the first frequency ① is emitted for a second time period △t2, an ultrasonic wave having the third frequency ③ lower than the second frequency ② is emitted for a third time period △t3, an ultrasonic wave having the fourth frequency ④ higher than the third frequency ③ is emitted for a fourth time period △t4, an ultrasonic wave having the fifth frequency ⑤ lower than the fourth frequency ④ is emitted for a fifth time period △t5, and an ultrasonic wave having the sixth frequency ⑥ higher than the fifth frequency ⑤ is emitted for a sixth time period △t6.

According to this, the frequency of the ultrasonic wave from the ultrasonic generator 100 is made not to interfere with the frequency of the control signal from the remote controller r, and is made to vary to deal with various kinds of noxious insects.

In this instance, the first time period △t1, the second time period △t2, the third time period △t3, the fourth time period △t4, the fifth time period △t5, and the sixth time period △t6 which are time periods in which ultrasonic waves respectively having the first frequency ①, the second frequency ②, the third frequency ③, the fourth frequency ④, the fifth frequency ⑤, and the sixth frequency ⑥ are emitted may, or may not, be same.

That is, the first time period △t1, the second time period △t2, the third time period △t3, the fourth time period △t4, the fifth time period △t5, and the sixth time period △t6, i.e., the preset time periods may be longer than 5minutes and below 20minutes, and the time periods of the first time period △t1, the second time period △t2, the third time period △t3, the fourth time period △t4, the fifth time period △t5, and the sixth time period △t6 which form the preset order may also vary, continuously.

In this instance, the first time period △t1, the second time period △t2, the third time period △t3, the fourth time period △t4, the fifth time period △t5, and the sixth time period △t6 which are time periods in which ultrasonic waves respectively having the first frequency ①, the second frequency ②, the third frequency ③, the fourth frequency ④, the fifth frequency ⑤, and the sixth frequency ⑥ are emitted may be identical particular time periods in a range of over 7 minutes below 17 minutes, for an example, 12 minutes.

Or, ultrasonic waves of different frequencies may be made to be continuous for different time periods.

FIG. 5 illustrates a graph showing another example of a time versus a frequency of an ultrasonic wave from an ultrasonic generator 100 mounted to an air conditioner in accordance with a preferred embodiment of the present invention.

Alike the graph in FIG. 4, the graph in FIG. 5 also enables to make the frequency of the ultrasonic wave from the ultrasonic speaker 102 to avoid the infrared frequency IR as well as the repetitive increase and decrease of the frequency of the ultrasonic wave which can deal with various kinds of noxious insects and is emitted continuously for a preset time period to ensure a lifetime of the ultrasonic speaker.

Accordingly, the frequencies of the ultrasonic waves emitted for a first time period △t1', a second time period △t2', a third time period △t3', a fourth time period △t4', a fifth time period △t5', and a sixth time period △t6', may be a fifth frequency ⑤', a fourth frequency ④', a sixth frequency ⑥', a second frequency ②', a first frequency ①', and a third frequency ③', respectively.

Of course, the first time period △t1', the second time period △t2', the third time period △t3', the fourth time period △t4', the fifth time period △t5', and the sixth time period △t6', may be different from the first time period △t1, the second time period △t2, the third time period △t3, the fourth time period △t4, the fifth time period △t5, and the sixth time period △t6 in FIG. 4 respectively, and the fifth frequency ⑤', the fourth frequency ④', the sixth frequency ⑥', the second frequency ②', the first frequency ①', and the third frequency ③' may be different from the fifth frequency ⑤, the fourth frequency ④, the sixth frequency ⑥, the second frequency ②, the first frequency ①, and the third frequency ③ in FIG. 4, respectively. That is, by diversifying the frequencies of the ultrasonic waves from the ultrasonic generator 100 further, a subdivided insecticide function can be provided.

The ultrasonic generator 100 does not emit the ultrasonic waves of identical frequencies and identical order every time, but can emit the ultrasonic waves of different frequencies (particular frequencies within a range of 20 kHz ~ 100 kHz which evade the IR) and in a new order every time.

This is for improving a lifetime of the ultrasonic generator 100 and preventing the noxious insects from developing resistance. For an example, the ultrasonic generator 100 can be made to emit the ultrasonic waves at the frequencies for the time periods as shown in FIG. 4B, at the frequencies for the time periods as shown in FIG. 5 in a next time, and at the frequencies for the time periods not shown in FIG. 4B or 5.

In the ultrasonic generator 100 emits the ultrasonic wave continuously, the ultrasonic generator 100 can emit the ultrasonic waves at the frequencies for the time periods as shown in FIG. 4B, and thereafter, at the frequencies for the time periods as shown in FIG. 5.

Of course, it is apparent that the ultrasonic generator 100 can emit the ultrasonic wave at the repetitive increase and decrease frequencies and time periods not shown in FIGS. 4B and 5 if in the case of continuous operation.

FIGS. 6A and 6B illustrate graphs showing a frequency of an input signal to an ultrasonic speaker of an ultrasonic generator 100 in accordance with another preferred embodiment of the present invention versus impedance and a time versus a frequency of the ultrasonic speaker 102, respectively.

Referring to FIG. 6A, the frequency of the input signal to the ultrasonic speaker 102 and an intrinsic impedance of the ultrasonic speaker 102 are inversely proportional, substantially. And, it can be assumed that if the frequency of the input signal becomes higher, a sound pressure or power of the ultrasonic wave becomes greater.

And, the impedance of the ultrasonic speaker 102 itself varies momentarily with variation of the frequency of the input signal.

That is, if the impedance of the ultrasonic speaker 102 has a downward concave portion, i.e., a minimum value momentarily, the power or sound pressure of the ultrasonic wave can be maximized.

Therefore, since the power or sound pressure of the ultrasonic wave can be amplified if the input signal has the particular frequency and the impedance has a small value momentarily, it is necessary to review a relation between the frequency and the impedance of the input signal.

And, according to an insecticide performance test of the ultrasonic generator, the frequency of the ultrasonic wave having the insecticide function is not the same to all kinds of noxious insects. Moreover, it is verified that the frequency at which the insecticide function is activated may varied even to the same kind of noxious insect.

Therefore, it is preferable that the frequency of the ultrasonic wave varied in emitting the ultrasonic wave having the insecticide function.

As shown in the graph in FIG. 6A illustrating a frequency of an input signal to the ultrasonic speaker 102 versus impedance, the frequency of an input signal to the ultrasonic speaker 102 is inversely proportional to the impedance, substantially.

The frequency of an input signal to the ultrasonic speaker is fixed by the following method. As shown in FIG. 6A illustrating a frequency of an input signal to the ultrasonic speaker 102 versus impedance, the frequency of the input signal may be fixed as the first frequency ①, the second frequency ②, the third frequency ③, the fourth frequency ④, the fifth frequency ⑤, and the sixth frequency ⑥.

That is, a resonant frequency of the ultrasonic speaker can be fixed with reference to a test value on impedance output of the ultrasonic speaker for a pulse input of which frequency varies. The resonant frequency of the ultrasonic speaker 102 shown in FIG. 6A can be fixed as the first frequency ①, the second frequency ②, the third frequency ③, the fourth frequency ④, the fifth frequency ⑤, and the sixth frequency ⑥.

Strictly speaking, the first frequency ①, the second frequency ②, the third frequency ③, the fourth frequency ④, the fifth frequency ⑤, and the sixth frequency ⑥ can be frequencies in the vicinity of the resonant frequencies of frequencies in a range of 20 kHz ~ 100 kHz. That is, though a plurality of minimum values are the same on the graph, it is not necessary to specify a frequency at which the impedance becomes the minimum exactly, but frequencies in the vicinity of frequencies at which the impedance becomes the minimum can be used.

Accordingly, it is required to understand that the resonant frequency in the following description includes a frequency in the vicinity of a frequency at which the impedance becomes the minimum in addition to an exact frequency at which the impedance becomes the minimum.

And, it is preferable that the ultrasonic generator 100 emits at least four ultrasonic waves of the repetitively increasing and decreasing resonant frequencies. FIG. 6A illustrates the ultrasonic generator 100 which emits total six ultrasonic waves having the repetitively increasing and decreasing resonant frequencies, respectively.

Referring to FIG. 6A, the resonant frequency of the ultrasonic speaker can be fixed with reference to a test value on impedance output of the ultrasonic speaker for a pulse input of which frequency varies, and as shown in FIG. 6A, a plurality of resonant frequencies can be obtained from one test graph.

Referring to FIG. 6A, the first frequency ①, the second frequency ②, the third frequency ③, the fourth frequency ④, the fifth frequency ⑤, and the sixth frequency ⑥ are frequencies of which impedance drops momentarily lower than adjacent frequencies, respectively.

Therefore, a sound pressure or power higher than adjacent frequencies can be obtained from the first frequency ①, the second frequency ②, the third frequency ③, the fourth frequency ④, the fifth frequency ⑤, and the sixth frequency ⑥, respectively.

Particularly, since the power or the sound pressure can act as a factor that fixes a travel distance of the ultrasonic wave, the power or the sound pressure is important.

Since the ultrasonic wave is a sound wave too, the longer the travel distance, the ultrasonic wave is involved in reduction of amplitude thereof until the ultrasonic wave disappears. It is favorable that the power or the sound pressure of the ultrasonic wave is maximized under the same condition.

Referring to FIG. 6A, the first frequency ①, the second frequency ②, the third frequency ③, the fourth frequency ④, the fifth frequency ⑤, and the sixth frequency ⑥ of each of the ultrasonic waves from the ultrasonic generator are in a range of 20kHz to 100kHz. And, the first frequency ①, the second frequency ②, the third frequency ③, the fourth frequency ④, the fifth frequency ⑤, and the sixth frequency ⑥ have frequencies which vary with preset time periods.

Referring to FIGS. 6A and 6B, the ultrasonic speaker emits ultrasonic waves having the first frequency ①, the second frequency ②, the third frequency ③, the fourth frequency ④, the fifth frequency ⑤, and the sixth frequency ⑥ for preset time periods, respectively.

As described before, the preset time periods the ultrasonic waves respectively having frequencies may be longer than 5 minutes and shorter than 20 minutes. If the preset time period is set to be about 12 minutes in view of test, a desired insecticide effect can be obtained and overload on the ultrasonic speaker can also be prevented.

And, the frequency of the ultrasonic wave emitted from the ultrasonic generator 100 may be a lowest frequency of the frequencies included to the preset order.

That is, since the frequency of the ultrasonic wave and the power and intensity of the ultrasonic wave can be related to a load on the ultrasonic speaker 102, in order to minimize load on the ultrasonic speaker 102 at the time of initial operation of the ultrasonic speaker 102, the frequency of the ultrasonic wave emitted from the ultrasonic generator 100 can be a lowest resonant frequency of the resonant frequencies included to the preset order.

In the meantime, FIG. 6B illustrates a graph showing a time versus a frequency of the ultrasonic wave from the ultrasonic generator 100. Since the repetitive increase and decrease of the frequency of the ultrasonic wave from the ultrasonic generator 100 is identical to FIGS. 4B and 5, description of which will be omitted.

Referring to FIG. 6B, the first frequency ①, the second frequency ②, the third frequency ③, the fourth frequency ④, the fifth frequency ⑤, and the sixth frequency ⑥ are the higher in an order of 20 kHz <the first frequency ① <the infrared frequency IR < the fifth frequency ⑤ < the third frequency ③ < the sixth frequency ⑥ < the fourth frequency ④ < the second frequency ② < 100 kHz.

And, the ultrasonic waves may be emitted by a method in which an ultrasonic wave having the first frequency ① is emitted for a first time period △t1, an ultrasonic wave having the second frequency ② higher than the first frequency ① is emitted for a second time period △t2, an ultrasonic wave having the third frequency ③ lower than the second frequency ② is emitted for a third time period △t3, an ultrasonic wave having the fourth frequency ④ higher than the third frequency ③ is emitted for a fourth time period △t4, an ultrasonic wave having the fifth frequency ⑤ lower than the fourth frequency ④ is emitted for a fifth time period △t5, and an ultrasonic wave having the sixth frequency ⑥ higher than the fifth frequency ⑤ is emitted for a sixth time period △t6.

By above method, the ultrasonic waves from the ultrasonic generator can be varied to deal with various kinds of noxious insects.

In this instance, the first time period △t1, the second time period △t2, the third time period △t3, the fourth time period △t4, the fifth time period △t5, and the sixth time period △t6 may, or may not, be same.

For an example, the first time period △t1, the second time period △t2, the third time period △t3, the fourth time period △t4, the fifth time period △t5, and the sixth time period △t6 may be 10 minutes or 12 minutes the same with one another, and it is possible to make the ultrasonic waves of different frequencies to continue for time periods different from one another, taking characteristics of the noxious insects dealing with relevant ultrasonic waves into account.

FIGS. 7A and 7B illustrate graphs showing another example of a frequency of an input signal to an ultrasonic speaker of an ultrasonic generator 100 versus impedance and a time versus a frequency of the ultrasonic speaker 102, respectively.

In detail, FIG. 7A illustrates a graph showing a frequency of a particular input signal to an ultrasonic speaker of the ultrasonic generator 100 versus impedance and FIG. 4B illustrates a graph showing a time versus a frequency of the ultrasonic wave from the ultrasonic speaker 102.

Referring to the graph in FIG. 7A, impedance of each ultrasonic speaker has an intrinsic characteristic. Different from the variation of the impedance shown in FIG. 6A, the variation of the impedance shown in FIG. 7A is consistent, fairly. And, minimum points of each section of the variation of the frequencies can be specified easily. It is verified that a predictable result of such a characteristic, fixable according to a vibration plate characteristic of the ultrasonic speaker 102, can be obtained in a case the vibration plate has great stiffness.

Therefore, the frequencies of the ultrasonic waves emitted for a first time period △t1', a second time period △t2', a third time period △t3', and a fourth time period △t4 may be first frequency ①', second frequency ②', third frequency ③' and fourth frequency ④', respectively. Of course, the first time period △t1', the second time period △t2', the third time period △t3' and the fourth time period △t4' may be different from the first time period △t1, the second time period △t2, the third time period △t3, and the fourth time period △t4 shown in FIG. 6 respectively, and the first frequency ①', the second frequency ②', the third frequency ③' and the fourth frequency ④' may be different from the first frequency ①, the second frequency ②, the third frequency ③ and the fourth frequency ④ shown in FIG. 6, respectively. That is, by diversifying the frequencies of the ultrasonic waves from the ultrasonic generator 100 further, a subdivided insecticide function can be provided.

Thus, in a case the ultrasonic speaker is mounted to the air conditioner for insecticide of the noxious insects, if the resonant frequency of the ultrasonic wave is determined taking impedance on the input signal which is an ultrasonic speaker characteristic into account, and the resonant frequency is used as a frequency of the input signal to the ultrasonic speaker, the insecticide function can be maximized.

As has been described, the air conditioner and the method for controlling the same of the present invention have the following advantages.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

Claims

An air conditioner comprising:

an indoor unit for air conditioning indoor air;

an ultrasonic generator including an ultrasonic speaker to emit an ultrasonic wave having a frequency varying within a preset frequency range, for emitting ultrasonic waves having a plurality of preset frequencies for preset time periods in a preset order respectively, the ultrasonic generator connected to the indoor unit with or without wire; and

an indoor unit control unit for controlling the indoor unit and the ultrasonic generator,

wherein the preset order is an order of increasing and decreasing the frequency of the ultrasonic wave, repeatedly.
The air conditioner as claimed in claim 1, wherein the preset frequency range is 20 kHz or more and 100 kHz or less.
The air conditioner as claimed in claim 1, wherein the plurality of preset frequencies are greater than the frequencies included to the preset order in number.
The air conditioner as claimed in claim 1, wherein the preset time periods are 5 minutes or longer and 20 minutes or shorter.
The air conditioner as claimed in claim 1, wherein the ultrasonic generator includes;

an ultrasonic generator control unit for controlling emission of the ultrasonic wave, and

a signal amplifying unit for amplifying an input signal to the ultrasonic speaker,

wherein the ultrasonic generator control unit controls the ultrasonic speaker according to the control signal from the indoor unit control unit.
The air conditioner as claimed in claim 5, wherein the frequencies of the ultrasonic waves included to the preset order are at least four frequencies, and stored in the ultrasonic generator control unit.
The air conditioner as claimed in claim 5, wherein the preset order or the preset time periods are at least two in number, and stored in the ultrasonic generator control unit.
The air conditioner as claimed in claim 1, wherein the frequency of the ultrasonic wave from the ultrasonic generator varies within a range excluding a range of an infrared remote controller frequency.
The air conditioner as claimed in claim 8, wherein the range of an infrared remote controller frequency is 34kHz or more and 42kHz or less.
The air conditioner as claimed in claim 8, wherein at least one of the plurality of preset frequencies is lower than the range of an infrared remote controller frequency.
The air conditioner as claimed in claim 10, wherein the frequency of the ultrasonic generator emitted initially upon putting the ultrasonic generator into operation is lower than the range of an infrared remote controller frequency.
The air conditioner as claimed in claim 1, wherein at least one of the plurality of frequencies from the ultrasonic generator is a frequency in the vicinity of a resonant frequency of the ultrasonic speaker.
The air conditioner as claimed in claim 12, wherein the resonant frequency of the ultrasonic speaker is two or more than two in number.
The air conditioner as claimed in claim 13, wherein the plurality of resonant frequencies of the ultrasonic speaker are fixed from test values of impedance output signals from the ultrasonic speaker on pulse form input signals of which frequency varies.
A method for controlling an air conditioner having a ultrasonic generator comprising the steps of:

a control signal generating step for generating a control signal for an ultrasonic generator to emit ultrasonic waves respectively having a plurality of preset frequencies for preset time periods in a preset order according to an user input, preset settings and preset conditions; and

an ultrasonic wave emitting step for emitting the ultrasonic waves according to the control signal generated in the control signal generating step,

wherein the preset order is an order of increasing and decreasing the frequency of the ultrasonic wave, repeatedly.
The method as claimed in claim 15, wherein the control signal generating step includes the step of generating the control signal to emit the ultrasonic wave of the lowest frequency of the frequencies included to the preset order, initially.
The method as claimed in claim 15, wherein the control signal generating step further includes the step of generating the control signal to vary the plurality of preset frequencies every time the ultrasonic generator is put into operation.
The method as claimed in claim 15, wherein the control signal generating step further includes the step of generating the control signal to change the preset order in a case the ultrasonic wave is emitted continuously after the ultrasonic wave is generated according to the preset order.
The method as claimed in claim 15, wherein the control signal generating step further includes the step of generating the control signal to fix a range of the plurality of preset frequencies excluding an infrared remote control unit frequency range.
The method as claimed in claim 15, wherein the control signal generating step further includes the step of generating the control signal to make at least one of the plurality of preset frequencies be in the vicinity of a resonant frequency of the ultrasonic speaker.