JP2005076976A - Air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air conditioner capable of surely solving a phase delay between a control speaker and a monitoring microphone to ensure sound reduction by enabling to obtain a proper acoustic transfer function while preventing generation of random noise as much as possible. <P>SOLUTION: Respective transfer functions between monitoring microphones 4 and 13 and control speakers 5 and 14 are measured according to operation of a remote control 20. The filter coefficient of an adaptive filter 30 is corrected according to the measured acoustic transfer function C. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an air conditioner having a muffler function for canceling out motor noise.

  Generally, an air conditioner is composed of an outdoor unit and an indoor unit. The outdoor unit is equipped with a compressor motor and an outdoor fan motor, and the indoor unit is equipped with an indoor fan motor. These motors emit a sound during operation, but the sound may become noise and cause discomfort to the occupants.

  An active silencer (ANC) is known as means for preventing such unpleasant sounds. The active silencer generates a sound for canceling the noise of the motor, emits the generated sound from the control speaker to the motor, and captures the sound emitted from the control speaker with a monitor microphone. The generation is corrected so that the generated sound is reduced.

  As a means for generating a canceling sound, an adaptive digital filter is known. In general digital filters, filter coefficients are determined according to characteristics such as cutoff frequency and application (IPF, HPF, BPF, etc.), while adaptive digital filters modify filter coefficients every time using error signals or the like. Is. FIG. 14 shows a basic configuration of this adaptive digital filter (hereinafter referred to as an adaptive filter).

  This adaptive filter works as follows. First, the output signal (control speaker output) y of the adaptive filter is compared with the desired signal (monitor microphone input) d, and the difference is obtained as the error signal e. In the adaptive filter algorithm, the coefficient of the adaptive filter is corrected using the error signal e so as to make the error signal e as small as possible. Therefore, a signal similar to the desired signal d is obtained as the output signal y of the adaptive filter.

  The adaptive filter control algorithm includes a least square algorithm and a sequential correction algorithm. The least square algorithm is an algorithm having excellent characteristics, but has a demerit that the amount of calculation is large. The sequential correction algorithm is an algorithm that obtains a coefficient that minimizes the mean square error while performing iterative and error, and is a practical algorithm that requires less computation than the least square algorithm. The minimum descent method is known as a typical example of this sequential correction algorithm. In practice, the LMS algorithm derived from the minimum descent method is often used. FIG. 15 shows an adaptive filter configuration using this LMS algorithm.

  From such an adaptive filter, as shown in FIG. 16, a sound signal having a waveform with the opposite phase and the same amplitude as that of the noise signal from the motor is obtained, and the sound signal is supplied to the control speaker. The noise from the motor is canceled (offset) by the output of the control speaker. The input signal level to the monitor microphone attenuates with cancellation.

  However, in the case of the active silencer using this adaptive filter, the phase delay of the sound between the control speaker and the monitor microphone is not taken into consideration. In order to perform reliable noise reduction, it is necessary to correct the phase delay.

  Therefore, conventionally, when the air conditioner is started, random noise (M-sequence signal) is output from the control speaker for about 10 to 20 seconds, and the acoustic transfer function between the control speaker and the monitor microphone is measured (identification). Some also correct the coefficient of the adaptive filter in accordance with the acoustic transfer function. By this correction, the phase delay of the sound between the control speaker and the monitor microphone is eliminated, and reliable mute can be performed.

Some devices measure an acoustic transfer function while actively canceling noise from a machine room in which a compressor is housed (for example, Patent Document 1).
Japanese Patent Laid-Open No. 2-226019

  As mentioned above, it is indispensable to measure the acoustic transfer function between the control speaker and the monitor microphone, but the random noise is controlled by each measurement, that is, every time the air conditioner is started. It is emitted from the speaker. The generation of this random noise is very unpleasant.

  As a countermeasure, the acoustic transfer function is measured at the manufacturing stage of the air conditioner, the measured acoustic transfer function is stored in a non-volatile memory, and the coefficient of the adaptive filter is read while reading the stored contents at the use stage of the air conditioner. There is an example of correcting the above.

  However, when the air conditioner is used, the compressor or fan may fail, and the control board may also fail. In this case, the cover of the outdoor unit or indoor unit is removed and the failed part is replaced. . However, since the cover is not originally attached with a high-accuracy tolerance, the acoustic transfer function becomes different from the initial measurement value in accordance with the replacement work. As a result, it becomes impossible to eliminate the phase lag of the sound between the control speaker and the monitor microphone, making it impossible to reliably mute the sound.

  In consideration of the above circumstances, the present invention can obtain an appropriate acoustic transfer function while preventing the generation of random noise as much as possible, and thereby the phase delay of the sound between the control speaker and the monitor microphone. The object is to provide an air conditioner that can reliably eliminate noise and can mute the sound.

  An air conditioner according to a first aspect of the present invention is a generating means for generating a sound for canceling the noise of a motor, a control speaker for emitting the sound generated by the generating means to the motor, and a sound emitted from the control speaker. A monitor microphone for capturing the received sound, measuring an acoustic transfer function between the monitor microphone and the control speaker, and generating the unit according to the acoustic transfer function and the sound captured by the monitor microphone And a remote control type operating device for driving operation, and a control means for measuring the acoustic transfer function according to the operation of the operating device. .

  According to a third aspect of the present invention, there is provided an air conditioner for generating a canceling sound for a motor noise, a control speaker for emitting the sound generated by the generating means toward the motor, and generating the sound from the control speaker. A monitor microphone for capturing the received sound, measuring an acoustic transfer function between the monitor microphone and the control speaker, and generating the unit according to the acoustic transfer function and the sound captured by the monitor microphone And amplifying circuit for amplifying the sound supplied to the control speaker, storage means for storing the specifications of the control speaker, and the storage contents of the storage means And a control means for controlling the amplification degree of the amplifier circuit.

  In the air conditioner of the present invention, it is possible to obtain an appropriate acoustic transfer function while preventing random noise as much as possible, thereby reliably eliminating the phase delay of the sound between the control speaker and the monitor microphone. And reliable mute.

[1] A first embodiment of the present invention will be described below with reference to the drawings.
In FIG. 1, reference numeral 1 denotes an outdoor unit, which includes a compressor 2, an outdoor fan 3, a monitor microphone 4, a control speaker 5, an active silence control board (hereinafter referred to as an ANC control board) 6, and a control board 7. . The monitor microphone 4 captures sound emitted from the control speaker 5. The control speaker 5 emits a noise canceling sound toward the motor of the outdoor fan 12 (an outdoor fan motor 12M described later).

The ANC control board 6 generates noise canceling sound for the outdoor fan motor 12M through serial communication with the control board 7. The control board 7 controls the outdoor unit 1.
An indoor unit 11 includes an indoor fan 12, a monitor microphone 13, a control speaker 14, an active mute control board (hereinafter referred to as an ANC control board) 15, and a control board 16. The monitor microphone 13 captures sound emitted from the control speaker 14. The control speaker 14 emits a noise canceling sound toward a motor (compressor motor 2M described later) of the compressor 2. The ANC control board 15 generates noise canceling sound for the compressor motor 2M through serial communication with the control board 16. The control board 16 controls the entire indoor unit 11 and the outdoor unit 1.

  The outdoor unit 1 and the indoor unit 11 are connected by a crossover pipe 10 and a cable (not shown) to constitute an air conditioner. In addition to the power supply line, the cable includes a signal line for performing full-duplex power supply communication between the control board 7 of the outdoor unit 1 and the control board 16 of the indoor unit 11.

  Reference numeral 20 denotes a remote control type operating device (hereinafter referred to as a remote controller) for driving operation, which has a liquid crystal display unit 21 and various operation buttons, and measures various code setting buttons and acoustic transfer functions on a panel surface with an upper cover opened. It has an instruction button 22 and transmits / receives various data to / from the outdoor unit 11 by infrared light.

  A specific configuration of the ANC control board 6 and the control board 7 in the outdoor unit 1 and a specific configuration of the ANC control board 15 and the control board 16 in the outdoor unit 11 are shown in FIG.

  The ANC control board 6 is a controller that generates a digital sound signal for noise cancellation for the compressor motor 2M, a ROM for program storage, a RAM for data storage, and acoustic transmission between the monitor microphone 4 and the control speaker 5. Non-volatile memory for storing the function C and the specifications of the control speaker 5, for example, E2PROM, serial communication circuit (UART) for data transmission / reception with the control board 7, and analog digital sound signal generated by the control unit D / A converter for converting into sound signal, sound output circuit for amplifying the converted analog sound signal and supplying it to control speaker 5, sound input circuit for amplifying analog sound signal input from monitor microphone 4, and amplification An A / D converter that converts the analog sound signal thus converted into a digital sound signal and supplies the digital sound signal is provided.

  The control board 7 is a control unit serving as the center of control, ROM for program storage, RAM for data storage, nonvolatile memory such as E2PROM, compressor motor drive circuit for driving the compressor motor 2M, and data transmission / reception with the ANC control board 6 Serial communication circuit (UART), A / D converter that converts the detected temperature of the outdoor temperature sensor 8 into digital data and supplies it to the control unit, a fan motor drive circuit that drives the outdoor fan motor 3M, and an indoor control board 16 has a power supply full duplex communication circuit for data transmission / reception with 16. The noise of the compressor motor 2M, which is a noise source, has a correlation with the rotor position (rotation angle) of the compressor motor 2M, and a voltage signal whose level changes according to the rotor position is detected from the compressor motor drive circuit. The detection signal is supplied to the control unit as a reference signal for digital sound generation. This reference signal is supplied from the control unit to the control unit of the ANC control board 6 via the serial communication circuit (UART).

  The ANC control board 15 is a controller for generating a digital sound signal for canceling the noise of the indoor fan motor 12M, a ROM for storing programs, a RAM for storing data, and the sound between the monitor microphone 13 and the control speaker 14. A non-volatile memory for storing the transfer function C and the specifications of the control speaker 14, such as an E2PROM, a serial communication circuit (UART) for data transmission / reception with the control board 16, and a digital sound signal generated by the control unit A D / A converter for converting the analog sound signal, a sound output circuit for amplifying the converted analog sound signal and supplying the analog sound signal to the control speaker 14, a sound input circuit for amplifying the analog sound signal input from the monitor microphone 13, It has an A / D converter that converts the amplified analog sound signal into a digital sound signal and supplies it to the control unit

  The control board 16 includes a control unit serving as the center of control, a ROM for program storage, a RAM for data storage, a non-volatile memory such as E2PROM, an infrared communication circuit for transmitting and receiving infrared light with the remote controller 20, and an ANC control board 15. Serial communication circuit (UART) for data transmission / reception, an A / D converter that converts the detected temperature of the indoor temperature sensor 17 into digital data and supplies it to the control unit, a fan motor drive circuit that drives the indoor fan motor 12M, and the outdoor side A power supply full-duplex communication circuit for data transmission / reception with the control board 7 is provided. The sound of the indoor fan motor 12M, which is a noise source, has a correlation with the rotor position (rotation angle) of the indoor fan motor 12M, and a voltage signal whose level changes according to the rotor position is detected from the fan motor drive circuit. The detection signal is supplied to the control unit as a reference signal for digital sound generation. This reference signal is supplied from the control unit to the control unit of the ANC control board 15 via the serial communication circuit (UART).

  Each control unit of the ANC control boards 6 and 15 is equipped with an adaptive digital filter (hereinafter referred to as an adaptive filter) 30 shown in FIG. 3 as generating means for generating a canceling sound for the noise of the motor. The adaptive filter 30 includes a FIR (Finite Impulse Response) digital filter and an adaptive FIR, and generates a sound signal having a waveform with the same phase and opposite phase as the reference signal corresponding to the motor sound. In FIG. 3, the lower block shows processing for sequentially measuring the acoustic transfer function C between the monitoring microphone and the control speaker while generating random noise (M-sequence signal). The upper part shows a process of generating a sound signal for noise cancellation while sequentially correcting the filter coefficient of the adaptive filter 30 according to the measured acoustic transfer function C. FIG. 4 shows a temporal change of the error signal e required in these processes.

Next, the overall operation of the air conditioner will be described with reference to the flowchart of FIG.
A standby process for receiving a command from the remote controller 20 is executed on the control board 16 of the indoor unit 11 (step 101). In this standby processing, as shown in the flowchart of FIG. 6, the input of authentication information such as an ID number or password from the remote controller 20 is waited (step 111), and whether the input data matches the data registered in advance in the E2PROM. It is determined whether or not (step 112). If they match, the reception of the maintenance command from the remote controller 20 is permitted based on the determination that the operator of the remote controller 20 is a worker who has been released from maintenance (step 113).

  At the time of this permission, when the operator presses the measurement instruction button 22 of the remote controller 20 to transmit a measurement command from the remote controller 20 and is received by the control board 16 of the indoor unit 11 (YES in step 102), The measurement processing of the acoustic transfer function C is executed on the ANC control boards 6 and 15 for a predetermined time, for example, several tens of seconds (step 103). Along with this measurement, the result of convergence of the error signal e (see FIG. 4) is diagnosed (step 104). This determination of convergence is made based on whether or not the error signal when a predetermined time elapses falls below a predetermined value as shown in FIG. When it falls below the predetermined value, it is judged as normal, and when it falls below the predetermined value, it is judged as abnormal. Causes of such an abnormality include failure of the monitor microphone and control speaker, disconnection of wiring, and the like.

  If the error signal e is reliably converged, each measured acoustic transfer function C is updated and stored in each E2PROM under the judgment that the measurement has been completed normally (YES in Step 105) (Step 106). Then, data indicating that the measurement has been completed normally is notified to the remote controller 20 and displayed on the liquid crystal display unit 21 of the remote controller 20 (step 107).

  If the error signal e has not converged (NO in step 105), data to that effect (measurement NG) is notified to the remote controller 20 and displayed on the liquid crystal display unit 21 of the remote controller 20 (step 108). In accordance with this display, the worker can press the measurement instruction button 22 of the remote controller 20 again to execute the measurement process of each acoustic transfer function C again.

  When the compressor or fan breaks down, or the cover of the outdoor unit 1 or the indoor unit 11 is removed due to a malfunction of the control board, the acoustic transfer function C changes. By pressing the button 22, new acoustic transfer functions C in the outdoor unit 1 and the indoor unit 11 can be measured and updated and stored in the E2PROM. The filter coefficient of each adaptive filter 30 is corrected based on each acoustic transfer function C that has been updated and stored, and the phase delay of the sound between the control speaker 5 and the monitor microphone 4 and the control speaker 14 and the monitor microphone. The phase delay of the sound between 13 and 13 can be surely eliminated. Thereby, the noise of the compressor motor 2M and the noise of the indoor fan motor 12M can be canceled reliably, and the occupant is not uncomfortable.

  In particular, it is only necessary to measure the acoustic transfer function C by generating random noise only when necessary, such as when the cover is removed, so there is no need to generate random noise every time the air conditioner is started, and it is quiet. .

  The sound output circuit of the ANC control boards 6 and 15 has an amplifier circuit having a plurality of feedback resistors 0Ω, 1RΩ,... 7RΩ as shown in FIG. Each feedback resistor is selectively turned on by opening and closing the electronic switches Bit0, Bit1,... Bit7, and the amplification degree of the amplifier circuit is changed by the selective turning on. The electronic switches Bit0, Bit1,..., Bit7 are controlled to be opened and closed by the control unit based on the specifications of the control speakers 5 and 14 stored in advance in the E2PROM, for example, rated input and rated impedance. For example, when a large level of sound is required for noise cancellation, control speakers 5 and 14 having a large rated input are employed, so that the amplification degree of the amplifier circuit is increased in accordance with the adoption. The electronic switch is controlled to open and close. That is, as the rated input of the control speakers 5 and 14 increases, a feedback resistor having a smaller resistance value is inserted, and the amplification degree of the amplifier circuit is increased.

  Also, the sound input circuit of the ANC control boards 6 and 15 has an amplifier circuit having a plurality of feedback resistors 0Ω, 1RΩ,... 7RΩ as shown in FIG. Each feedback resistor is selectively turned on by opening and closing the electronic switches Bit0, Bit1,... Bit7, and the amplification degree of the amplifier circuit is changed by the selective turning on. The electronic switches Bit0, Bit1,... Bit7 are controlled to be opened and closed by the control unit based on the rated input and the rated impedance, which are the specifications of the control speakers 5 and 14 stored in advance in the E2PROM. For example, when a large level of sound is required for noise cancellation, control speakers 5 and 14 having a large rated input are adopted, so that the amplification degree of the amplifier circuit is lowered in accordance with the adoption. The electronic switch is controlled to open and close. That is, the larger the rated input of the control speakers 5 and 14 is, and the larger the canceling sound is generated, the more the feedback resistor having a larger resistance value is inserted and the amplification degree of the amplifier circuit is lowered. The input sound signal can be appropriately amplified without being saturated.

[2] A second embodiment will be described.
As shown in FIG. 9, after a measurement command button 22 of the remote controller 20 is pressed by an operator and a measurement command is transmitted from the remote controller 20 and received by the control board 16 of the indoor unit 11 (YES in step 102). It is determined whether or not the compressor motor 2M is operating (step 201). If it is in operation (YES in step 201), the operation of the compressor motor 2M is stopped (step 202). After this stop, the measurement processing of the acoustic transfer function C is executed for several tens of seconds on the ANC control boards 6 and 15 (step 103).

  Thus, by measuring the acoustic transfer function C in a state where the operation of the compressor motor 2M is stopped, the acoustic transfer function C can be measured more appropriately without being affected by the sound of the compressor motor 2M.

  Other configurations, operations, and effects are the same as those in the first embodiment.

[3] A third embodiment will be described.
As shown in FIG. 10, the measurement command button 22 of the remote controller 20 is pressed by an operator and a measurement command is transmitted from the remote controller 20 and received by the control board 16 of the indoor unit 11 (YES in step 102). It is determined whether or not the compressor motor 2M is operating (step 201). If it is in operation (YES in step 201), the operation of the compressor motor 2M is stopped (step 202). After this stop, the ambient noise level is detected through the monitor microphones 4 and 13 in the control unit of the ANC control boards 6 and 15 (step 203).

  If the detected noise level is less than or equal to a predetermined value (NO in step 204), measurement processing of the acoustic transfer function C by the ANC control boards 6 and 15 is permitted (step 103).

  However, if the detected noise level is larger than a predetermined value (YES in step 204), the elapsed time is counted (step 205), and the count time is compared with a certain time, for example, 10 seconds ( Step 206). If the noise level falls below a predetermined value (NO in step 204) before the count time reaches 10 seconds (NO in step 206), the measurement process of the acoustic transfer function C is allowed (step 103).

  If the noise level does not fall below the predetermined value (YES in step 204) and the count time reaches 10 seconds (YES in step 206), the measurement process of the acoustic transfer function C is prohibited, and data indicating the prohibition. (Measurement NG) is notified to the remote controller 20 and displayed on the liquid crystal display unit 21 of the remote controller 20 (step 207). In accordance with this display, the operator can take measures to reduce the ambient noise, and then press the measurement instruction button 22 of the remote controller 20 again to execute the measurement processing of each acoustic transfer function C again.

  In this way, the operation of the compressor motor 2M is stopped, and the sound transfer function C is measured only when the ambient noise level is as low as a predetermined value or less, so that the sound of the compressor motor 2M and the ambient noise are affected. Therefore, the acoustic transfer function C can be measured more appropriately.

  Other configurations, operations, and effects are the same as those in the first embodiment.

[4] A fourth embodiment will be described.
As shown in FIG. 11, the measurement command button 22 of the remote controller 20 is pressed by an operator and a measurement command is transmitted from the remote controller 20 and received by the control board 16 of the indoor unit 11 (YES in step 102). ), The circuits of the ANC control boards 6 and 15 are diagnosed by the control boards 7 and 16 (step 301). If the circuits of the ANC control boards 6 and 15 are functioning normally (YES in Step 302), the control unit of the ANC control boards 6 and 15 detects the ambient noise level through the monitor microphones 4 and 13 ( Step 203).

  If the detected noise level is less than or equal to a predetermined value (NO in step 204), measurement processing of the acoustic transfer function C by the ANC control boards 6 and 15 is permitted (step 103).

  However, if the detected noise level is larger than a predetermined value (YES in step 204), the elapsed time is counted (step 205), and the count time is compared with a certain time, for example, 10 seconds ( Step 206). Before the count time reaches 10 seconds (NO in step 206), if the noise level falls below a predetermined value (NO in step 204), the measurement process of the acoustic transfer function C is permitted (step 103).

  If the noise level does not fall below the predetermined value (YES in step 204) and the count time reaches 10 seconds (YES in step 206), the measurement process of the acoustic transfer function C is prohibited, and data indicating the prohibition. (Measurement NG) is notified to the remote controller 20 and displayed on the liquid crystal display unit 21 of the remote controller 20 (step 207). In accordance with this display, the operator can take measures to reduce the ambient noise, and then press the measurement instruction button 22 of the remote controller 20 again to execute the measurement processing of each acoustic transfer function C again.

  When the circuits of the ANC control boards 6 and 15 are abnormal (NO in step 302), data indicating the abnormality (measurement NG) is notified to the remote controller 20 and displayed on the liquid crystal display unit 21 of the remote controller 20 (step) 303). According to this display, the worker can take appropriate measures such as removing the ANC control boards 6 and 15 and replacing them with normal ones.

  Thus, by diagnosing the circuits of the ANC control boards 6 and 15, the reliability related to the measurement of the acoustic transfer function C can be improved.

  Other configurations, operations, and effects are the same as those in the first embodiment.

[5] A fifth embodiment will be described.
As shown in FIGS. 12 and 13, the ANC control boards 6 and 15 are integrated into the control boards 7 and 16, and the measurement of the acoustic transfer function C is executed by the control unit of the ANC control boards 6 and 15.
By adopting this integrated configuration, cost reduction and shape reduction can be achieved.
Other configurations, operations, and effects are the same as those in the first embodiment.

  [6] It should be noted that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine the component covering different embodiment suitably.

The block diagram which shows the structure of 1st, 2nd, 3rd, 4th embodiment of this invention. The block diagram which shows the specific structure of the ANC control board in FIG. 1, and a control board. The figure for demonstrating the measurement of the adaptive filter structure and acoustic transfer function in each embodiment of this invention. The figure which shows the time change of the error signal e in FIG. The flowchart for demonstrating the effect | action of 1st Embodiment. FIG. 6 is a diagram specifically illustrating command reception standby processing in the flowchart of FIG. 5. The block diagram which shows the structure of the sound output circuit in each embodiment. The block diagram which shows the structure of the sound input circuit in each embodiment. The flowchart for demonstrating the effect | action of 2nd Embodiment. The flowchart for demonstrating the effect | action of 3rd Embodiment. The flowchart for demonstrating the effect | action of 4th Embodiment. The block diagram which shows the structure of 5th Embodiment of this invention. The block diagram which shows the specific structure of the control board in FIG. The figure which shows the basic composition of a general adaptive filter. The figure which shows the adaptive filter structure using a general LMS algorithm. The figure which shows the waveform of a general noise signal, a control speaker output signal, and a monitor microphone input signal.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Outdoor unit, 2 ... Compressor, 2M ... Compressor motor, 3 ... Outdoor fan, 4 ... Monitor microphone, 5 ... Control speaker, 6 ... ANC control board, 7 ... Control board, 11 ... Indoor unit, 12 ... Indoor Fan, 12M ... indoor fan motor, 13 ... monitor microphone, 14 ... control speaker, 15 ... ANC control board, 16 ... control board, 20 ... remote control (operator), 21 ... liquid crystal display, 22 ... measurement instruction button

Claims (3)

  A generating means for generating a sound for canceling the noise of the motor, a control speaker for emitting the sound generated by the generating means to the motor, and a monitor microphone for capturing the sound emitted from the control speaker, In an air conditioner that measures an acoustic transfer function between a monitor microphone and the control speaker, and corrects the sound generated by the generating means according to the acoustic transfer function and the sound captured by the monitor microphone An air conditioner comprising: a remote control type operation device for driving operation; and control means for executing measurement of the acoustic transfer function in response to operation of the operation device. The generation means includes a reference signal corresponding to a motor sound by correcting a coefficient according to an error signal that is a difference between a sound emitted from the control speaker and a sound captured by the monitor microphone. An adaptive digital filter that generates a sound signal having a waveform with the same phase and opposite phase,
The control means for determining the measurement of the acoustic transfer function by the control means to be normal when the error signal falls below a predetermined value within a predetermined time, and to determine that it is abnormal otherwise, and the determination result of the control means The air conditioner according to claim 1, further comprising: a control unit that causes the operation unit to display.   A generating means for generating a sound for canceling the noise of the motor, a control speaker for emitting the sound generated by the generating means to the motor, and a monitor microphone for capturing the sound emitted from the control speaker, In an air conditioner that measures an acoustic transfer function between a monitor microphone and the control speaker, and corrects the sound generated by the generating means according to the acoustic transfer function and the sound captured by the monitor microphone An amplifier circuit for amplifying the sound supplied to the control speaker; a storage means for storing the specifications of the control speaker; and a control means for controlling the amplification degree of the amplifier circuit in accordance with the stored contents of the storage means And an air conditioner.

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