JPH08200780A - Air conditioner - Google Patents

Abstract

(57) [Summary] [Purpose] To provide an air conditioner capable of quieter operation by canceling operation noise generated in a heat exchanger or a blower. [Composition] The frequency and level of the standard waveform muffling signal are adjusted according to the number of revolutions Na of the blower 12, and the phase is adjusted according to the level of the detected sound of each microphone 34, and the muffling signal after the adjustment is adjusted. Is converted into an actual sound by each speaker 32 and is output to the ventilation path 30. This noise cancels the driving noise.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art An air conditioner, as shown in FIGS. 21 and 22, has an indoor unit 101 attached to an air-conditioned room.
And an outdoor unit 102 installed outside the building via a refrigerant pipe (and wiring) 103. The main body of the indoor unit 101 is often of a type that is attached and fixed to the wall surface of the air-conditioned room. 104 is a power plug, 105 is a remote control receiver, and 106 is a drain hose.

The indoor unit 101 includes a front panel 2
A unit body 1 in which a rear plate 3 and a rear plate 3 are combined, and a heat exchanger 11 accommodated and arranged inside the unit body 1 so as to face each other.
And a blower 12 and the like.

In the front panel 2, the suction port 4 is provided in the front surface 2b and the upper surface 2c so as to face the heat exchanger 11.
Is provided, and suction grilles 5 and 6 in which a large number of horizontal rails and vertical rails are combined at a predetermined interval are fitted therein.

The suction grilles 5, 6 and the heat exchanger 11
A filter 10 is removably inserted between and to capture dust contained in the air in the air-conditioned room and filter it.
After using for a predetermined period of time, the filter 10 must be removed to remove and clean the trapped dust.

Further, the front panel 2 is formed with an air outlet 9 at the lower front portion thereof. A part of the drain pan 13 arranged below the heat exchanger 11 serves as a nose 14 for guiding the air blown from the blower 12.
A blow-out ventilation passage 18 is formed between the air blower 4 and the air outlet 9. The outlet 9 is provided with a plurality of left and right louvers 20 and a plurality of upper and lower louvers 21.

[0007]

A heat exchanger 11 and a blower 12 are arranged inside the unit main body 1,
Due to the air-conditioning action, these heat exchanger 11 and blower 12
Is an unavoidable source of driving noise.

The operation noise includes wind noise of heat exchange air flowing through the fins of the heat exchanger 11, flow noise of the refrigerant flowing through the heat exchange pipe, operation noise of the blower motor, and fan noise of fan rotation. These operation noises impair quiet operation, and it is desirable to reduce them as much as possible.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an air conditioner capable of canceling operation noise generated in a heat exchanger or a blower and performing a quieter operation. .

[0010]

An air conditioner according to a first aspect of the present invention is provided with a unit main body having a suction port and a blowout port, and having a ventilation channel from the suction port to the blowout port, and the ventilation channel. A heat exchanger and an air blower, a means for emitting a standard-waveform muffling signal having a predetermined frequency and level, and a position facing the ventilation passage or in the vicinity of the air outlet, which are provided to convert the muffling signal into sound. A speaker, a microphone provided at a predetermined position of the unit body, a rotation speed sensor for detecting the rotation speed of the blower, and the frequency and level of the silencing signal are temporarily adjusted according to the detection result of the rotation speed sensor. However, there is provided an adjusting means for adjusting the phase of the muffling signal according to the level of the sound detected by the microphone.

In the air conditioner of the second invention, in the first invention, a speaker is provided downstream of the blower at a position facing the ventilation passage, and a microphone is upstream of the speaker at a position facing the ventilation passage. Not on the side but on the downstream side.

In the air conditioner of the third invention, in the first invention, the speaker is provided on the downstream side of the blower at the position facing the ventilation passage, and the microphone is provided on the outer peripheral portion of the unit main body. .

In the air conditioner of the fourth invention, a plurality of the speakers and microphones of the second invention are provided along the axial direction of the cross flow fan constituting the blower.

In the air conditioner of the fifth invention, the adjusting means in the first invention adjusts the frequency and level of the muffling signal according to the detection result of the rotation speed sensor, and the blade of the cross flow fan constituting the blower. Set according to the number.

An air conditioner according to a sixth aspect of the present invention is the air conditioner according to any one of the first to fifth aspects of the present invention, including means for generating white noise and means for superimposing the white noise on the silencing signal.

An air conditioner according to a seventh aspect of the present invention is a unit main body having an inlet and an outlet, and an air passage extending from the inlet to the outlet, a heat exchanger and a random pitch provided in the air passage. Of a cross-flow fan, means for emitting a muffling signal with a standard waveform having a predetermined frequency and level, and a position provided in the vicinity of the air passage or in the vicinity of the air outlet for converting the muffling signal into sound. Speaker, a microphone provided at a predetermined position of the unit body, a rotational position sensor for detecting the rotational position of the blower, a rotational speed sensor for detecting the rotational speed of the blower, and the detection result of the rotational speed sensor. The frequency and level of the muffling signal are adjusted once in accordance with the And a adjusting means for adjusting in response to the detection result.

In the air conditioner of the eighth invention, the rotational position sensor of the seventh invention has several projections arranged along the peripheral edge of the axial end of the blower, and the projections are opposed to each other. It is composed of a light emitting element and a light receiving element for outputting a rotational position signal.

In the air conditioner of the ninth invention, the rotational position sensor of the seventh invention has several reflecting members arranged along the peripheral edge of the axial end of the blower, and light to these reflecting members. It is composed of a light emitting element that emits light and a light receiving element that receives the reflected light from the reflecting member, and outputs a rotational position signal.

An air conditioner of a tenth aspect of the invention is the air conditioner according to any one of the first to ninth aspects of the invention, which is provided at a position facing a ventilation path of a cylindrical enclosure whose end portions have a substantially arc-shaped cross section. A speaker and a sound absorbing material were provided in the enclosure.

[0020]

In the air conditioner of the first aspect of the invention, the frequency and level of the standard waveform silencing signal are adjusted according to the rotational speed of the blower, and the phase is adjusted according to the level of the sound detected by the microphone. The muffling signal after the adjustment is converted into an actual sound by the speaker. Since the standard waveform muffling signal is stored in advance, only a microphone for evaluation needs to be prepared, and a microphone for sound source detection is unnecessary, thus preventing the howling phenomenon.

In the air conditioner of the second invention, in the first invention, the sound from the blower toward the air outlet is canceled by the sound emitted from the speaker, and the sound passing through the position of the speaker is captured by the microphone.

In the air conditioner of the third invention, in the first invention, the sound from the blower toward the air outlet is canceled by the sound emitted from the speaker, and the sound around the unit body near the air outlet is captured.

In the air conditioner of the fourth aspect of the invention, in the third aspect of the invention, sound is output from a plurality of speakers along the axial direction of the cross flow fan in the blower. These sounds cancel the sound from the blower toward the air outlet. Then, the sound that has passed through the speaker position is captured by the microphone, so that even if the noise is different in the axial direction of the cross flow fan, the optimum silencing processing suitable for each location can be individually completed. Therefore, the silencing effect is enhanced.

In the air conditioner of the fifth aspect of the invention, in the first aspect of the invention, the frequency and level of the standard waveform silencing signal are set according to the detection result of the rotation speed sensor and the number of blades of the cross flow fan in the blower. Set accordingly. Therefore,
As the sound for muffling, a sound of a frequency and a level (amplitude) in consideration of the number P of blades of the cross flow fan 12b is generated, the operation noise can be effectively attenuated, and quiet operation can be obtained.

In the air conditioner of the sixth aspect of the invention, in any one of the first to fifth aspects of the invention, white noise is superimposed on the silencing signal, and both the silencing sound and the white noise effectively drive the operating noise. Is canceled.

In the air conditioner of the seventh invention, the frequency and level of the standard waveform silencing signal are adjusted according to the number of revolutions of the blower, and the phase is adjusted to the level of the sound detected by the microphone and the rotational position of the blower. Adjust accordingly. The muffling signal after the adjustment is converted into an actual sound by the speaker.

In the air conditioners of the eighth and ninth inventions,
In the seventh invention, since the rotational position of the blower is optically detected, it does not become a load of the blower sound. An air conditioner of a tenth aspect of the invention is the air conditioner according to any one of the first to ninth aspects of the invention, wherein the sound of the speaker is output to a position facing the ventilation path through the enclosure. That is, the sound for muffling emitted from the speaker is emitted toward the ventilation path while being transmitted in the fan axial direction by the enclosure. By adopting the enclosure, it is possible to perform the silencing processing in the fan axis direction with one speaker. Since the enclosure can be assembled in the unit body as a separate assembly, there is an advantage that the manufacturing becomes easy. The presence of the enclosure makes it possible to efficiently produce low-frequency sound as a sound for silencing. Since there is a sound absorbing material on the inner peripheral surface of the enclosure, there is no fear of generating resonance noise.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to the drawings. In the drawings, the same parts as those in FIGS. 21 and 22 are designated by the same reference numerals. 2 is an exploded view of the indoor unit 101 (a part of which is omitted),
FIG. 3 shows a cross section of the indoor unit 101. The unit main body 1 is composed of a housing in which a front panel 2 and a rear plate 3 are combined.

The front panel 2 has both side portions 2a having engaging portions for engaging the rear plate 3 and the front portion 2 provided with the suction port 4.
b and an upper surface portion 2c on which the upper surface suction grill 5 is formed.

A front suction grill (hereinafter referred to as a suction grill) 6 is rotatably supported on the front portion 2b of the front panel 2. The suction grill 6 is pivotally supported on the front surface portion 2b via a hinge (not shown) provided on the upper end portion, and the lower end portion becomes a free end.

The suction grill 6 is provided with a plurality of vertical bars 7 that are provided at wide intervals in the width direction and a large number of horizontal bars 8 that are provided at narrow intervals in the vertical direction. There is.
On the other hand, the lower end portion of the front panel 2 and the lower end portion of the rear plate 3 form the air outlet 9. A filter 10 is attached to a portion of the unit body 1 that is close to and faces the suction grill 6 and the upper suction grill 5. This filter 10
By opening the suction grill 6, the unit can be attached to and detached from the front surface of the suction port 4 of the unit body 1.

An air passage 30 is formed in the unit body 1 from the suction grilles 5 and 6 which are air inlets to the air outlet 9, and a heat exchanger 11 and a blower 12 are arranged in the air passage 30.

The heat exchanger 11 is of a so-called fin tube type in which a large number of fins are arranged in parallel with a narrow gap and a heat exchange pipe is penetrated through these fins, and here, the heat exchanger 11 is bent in multiple stages. The front heat exchanger 11A and the rear heat exchanger 11B bent so as to form an inverted V shape with respect to the front heat exchanger.

The blower 12 is in a position where it is covered by the front heat exchanger 11A and the rear heat exchanger 11B as if it were in the shape of an umbrella, and is connected to the drive motor 12a on one side and the rotary shaft of this drive motor. The cross-flow fan 12b has a substantially cylindrical outer shape, and a bearing 12c that axially supports the other end side shaft portion of the cross-flow fan. Cross flow fan 12b
Is configured by arranging a large number of blades in the circumferential direction.

A front drain pan 13 serving as a tray for water droplets adhering to the heat exchanger 11A is arranged along the lower end portion of the front heat exchanger 11A in a state of being inclined obliquely forward.
Then, a nose 14 for guiding the air blown from the blower 12 is formed in the rear portion of the front drain pan 13 facing the cross flow fan 12b, and the lower end surface of the front portion of the front drain pan 13 has a lower end surface of the outlet 9 on the front panel 2 side. The ventilation passage forming portion 15 is formed so as to extend along the upper edge.

The rear plate 3 has an upper surface portion 3a connected to the upper surface intake grill 5 of the front panel 2, both side portions 3b connected to both side portions of the front panel, and the rear heat exchanger 11B. A rear drain pan 16 along the lower end of the blower 12 and a back portion 3c having a ventilation passage forming portion 17 bent from the side portion of the blower 12 to the outlet 9.

That is, the ventilation passage forming portion 17 provided on the rear plate 3 and the ventilation passage forming portion 15 provided on the front drain pan 13 are provided from the blower 12 via the nose 14 to the outlet 9.
A blow-out air passage 18 communicating with the above is formed.

An airflow direction adjusting portion 19 is provided across the end of the blowout air passage 18 and the outlet 9. The wind direction adjusting unit 19 includes a plurality of left and right louvers 20 provided on the lower surface of the front drain pan 13 and upper and lower louvers 21.

Therefore, by performing the refrigeration cycle operation on the heat exchanger 11 and driving the blower 12, the air to be conditioned room is sucked into the unit main body 1 from the suction grilles 5 and 6 and passes through the heat exchanger 11. And exchange heat.

The heat exchanged air after the heat exchange is carried out by the blower 12
Through the ventilating passage 30, and is guided to the nose 14 and the blowing ventilating passage 18 and blown out from the outlet 9 into the air-conditioned room. At this time, the blowing direction can be arbitrarily set by the left and right louvers 20 and the upper and lower louvers 21.

In such a configuration, the speaker 32 is embedded via the mounting member 31 at a position facing the ventilation passage 30, for example, in the ventilation passage forming portion 17 on the downstream side of the blower 12. A plurality of the speakers 32 are provided along the axial direction of the cross flow fan 12b. Then, in the ventilation path forming unit 17, a plurality of microphones 34 are embedded at positions downstream of the speakers 32 and at positions corresponding to the speakers 32 via mounting members 33.

Each speaker 32 converts a muffling signal, which will be described later, into a sound, and outputs it to the air passage 30. Each microphone 34 catches the sound in the ventilation passage 30. The muffler shown in FIG. 1 is configured by using the speaker 32 and the microphone 34 as components.

Reference numeral 40 denotes a main control section, which comprises a memory 41, a plurality of frequency / amplitude adjusting sections 42, and a plurality of phase adjusting sections 43. A rotation speed sensor 50, a plurality of amplifiers 51, and the microphones 34 are connected to the main controller 40. The speaker 32 is connected to the output terminal of each amplifier 51.

The memory 41 corresponds to each speaker 32 and each microphone 34 in common, and stores a standard waveform muffling signal having a predetermined frequency and level (amplitude) as a sound source signal. The stored sound source signal is read during operation of the indoor unit and sent to each frequency / amplitude adjusting unit 42.

The rotation speed sensor 50 detects the rotation speed Na of the cross flow fan 12b. Alternatively, the rotation speed sensor 50 may not be used, and a rotation speed command signal to the blower 12 may be input to each frequency / amplitude adjusting unit 42.

The frequency / amplitude adjusting sections 42 and the phase adjusting sections 43 are prepared in the number corresponding to the number of the speakers 32 and the microphones 34. Frequency / amplitude adjustment unit 4
Reference numeral 2 temporarily adjusts the frequency and level (amplitude) of the sound source signal emitted from the memory 41 according to the detection result (rotational speed Na) of the rotational speed sensor 50. The frequency adjustment here is 50Hz, which is the frequency band of the sound that humans can easily sense.
It is performed by limiting to the range of 500Hz. Due to this limitation
The processing of the frequency / amplitude adjusting unit 42 is not burdened.

Specifically, when the rotation speed Na detected by the rotation speed sensor 50 is lower than the standard value, as shown in FIG. 4, the frequency is low (the phase angle φ is large) and the amplitude A is adjusted to be small. It When the rotation speed Na is equal to or higher than the standard value, the frequency is high (the phase angle φ is small) and the amplitude A is adjusted to be large as shown in FIG. 4 and 5, a sine wave is shown for easy understanding.

Thus, the operation sound of the blower 12 (the sound of the drive motor 12a) and the sound of the blower (the sound of the cross flow fan 12b)
In consideration of the above, and taking into consideration the wind noise of the heat exchange air 11 and the flow noise of the refrigerant passing through the heat exchange pipe, a sound deadening signal for canceling these sounds is created. This muffling signal is sent to the phase adjustment unit 43.

The phase adjusting unit 43 is a frequency / amplitude adjusting unit 4
The phase of the muffling signal passing through 2 is adjusted according to the actual sound level captured by the microphone 34. In particular,
The phase is adjusted so that the sound level captured by the microphone 34 is minimized. The silenced signal after the adjustment is amplified by the amplifier 51 and sent to the speaker 32.

[0050] Incidentally, noise, which was mixed a plurality of types of sound, frequencies F ₁ of the first order as follows to indicate the Fourier transform, the second-order frequency F _2, that ... n the following frequencies F _n So that the level (amplitude) at multiple certain frequencies
Grows larger. These specific frequencies F ₁ , F ₂ , ... F _n
Varies depending on the rotational speed Na of the cross flow fan 12b. Standard Waveform = As · sin (Ns · Fs + φ 0) ... (1) noise waveform of the primary frequency _{F 1 B 1 = A 1 ·} sin (1 · Na · Fs + φ 1) ... (2) the secondary frequency noise waveform B ₂ = a ₂ · sin at _{F 2 (2 · Na · Fs} + φ 2) ... (3) noise waveform at the third-order frequency _{F 3 B 3 = a 3 ·} sin (3 · Na · Fs + Φ ₃ ) ... (4) Noise waveform at _n - _th frequency F _n B _n = A _n · sin (n · Na · Fs + φ _n )… (5) A _n is the amplitude, F s is the frequency of the standard waveform, _{N s} is the standard rotation speed for obtaining the standard waveform, and φ _n is the phase angle.

Here, the amplitude A is set so that the total noise value B of the above equation (6) obtained by integrating the noises of the 1st to nth order is B = 0.
By adjusting _n and the phase angle φ _n , a phase opposite to the noise signal, that is, a muffling signal for canceling the noise can be obtained.

An example of the waveform of the noise signal is shown in FIG. 6, and the amplitude for each of the frequencies F ₁ , F ₂ , ... F _n is shown in FIG. In this way, the sound source signal of the standard waveform is adjusted by the rotation speed Na of the cross flow fan 12b to create a muffling signal, and the actual sound in the ventilation passage 30 is captured by the microphone 34 for evaluation, and the captured sound By adjusting the phase of the muffling signal according to the level and converting the phase of the muffler signal into an actual sound by each speaker 32, the driving noise can be reliably canceled. This enables quiet operation.

In this case, since the sound source signal of the standard waveform is stored in advance, only the microphone for evaluation needs to be prepared and the one for sound source detection is not necessary. That is, if there are both microphones for evaluation and sound source detection, there is a concern that a howling phenomenon will occur and adversely affect the muffling process, but since there is only the evaluation microphone 34, such a problem does not occur. Further, since there is no microphone for sound source detection, wind noise caused by the microphone is reduced.

It is usual that the pitch between the blades of the cross flow fan 12b has a "deviation" along the axial direction of the fan to prevent "beat" from occurring in the blowing noise. Due to the influence, the blowing sound is slightly different along the axial direction of the fan, but since a plurality of speakers 32 and microphones 34 are arranged along the axial direction of the cross flow fan 12b, noise is generated by the cross flow fan. Even if they are different in the axial direction of 12b, it is possible to individually complete the optimum silencing processing suitable for each location. This enhances the silencing effect.

Each speaker 32 and each microphone 3
Since 4 is only embedded in the ventilation passage forming portion 17 and faces the ventilation passage 30, wind noise due to each speaker 32 and each microphone 34 can be prevented, and the silencing effect is not impaired.

In the above embodiment, the speaker 32 is embedded in the ventilation path forming portion 17 via the mounting member 31, but as shown in FIG. 8, the speaker mounting opening 17a is formed in the ventilation path forming portion 17. At the same time, the peripheral edge of the opening 17a may be tapered and the speaker 32 may be directly fitted and attached thereto.

In this case, the cone paper of the speaker 32 and the peripheral portion of the opening 17a are flush with each other, and the diameter of the speaker 31 is actually "D" but apparently "L".
The sound radiation performance is improved. Moreover, the ventilation resistance is reduced by the amount of the mounting member 31 not provided, and the ventilation efficiency is improved.

In the above embodiment, each microphone 3
4 is provided in the ventilation path forming portion 17, but as shown in FIG.
It may be embedded in the vicinity of the outlet 9 and on the outer peripheral portion of the unit body 1, for example, the front surface 2b of the front panel 2. Alternatively, as shown in the same FIG. 9, as the vicinity of the air outlet 9,
It may be embedded under the rear plate 3.

As described above, when the microphone 34 is provided at a position where the blowing air does not hit, that is, since the blowing wind does not hit the microphone 34 at all, there is no wind noise, and the sound of the blowing air can be reliably detected. .

Further, although each speaker 32 is provided at a position facing the ventilation passage 30, it is not always necessary to do so, and if it is a place where a noise for muffling can be emitted toward the driving noise, the outlet 9 is provided. It may be anywhere, such as in the vicinity.

Although a plurality of speakers 32 and a plurality of microphones 34 are provided along the axial direction of the cross flow fan 12b, as shown in FIGS. 10 and 11, a ventilation passage 30 is provided above the cross flow fan 12b. A pair of speakers 32 are provided facing each other on both sides of the facing unit, and one microphone 34 is provided at an intermediate position between the speakers 32.
May be provided.

In this case, the sound for silencing emitted from both speakers 32 flows along the axial direction of the cross flow fan 12b,
This cancels the blast sound. Next, a second embodiment of the present invention will be described.

Here, as shown in FIG. 12, the superimposing section 44 is inserted between the respective frequency / amplitude adjusting sections 42 and the respective phase adjusting sections 43 of the main control section 40. further,
A white noise generator 45 is provided in the main controller 40,
The output signal of the white noise generating section 45 is supplied to each of the superposing sections 44.

The white noise generating section 45 emits a signal of "so-called" noise, so-called white noise, which is similar to the blowing noise of the air conditioner. The superimposing unit 44 superimposes the white noise from the white noise generating unit 45 on the muffling signal that has passed through the frequency / amplitude adjusting unit 42.

Also, paying attention to the fact that the blowing noise differs depending on the number P of blades of the cross flow fan 12b, a standard waveform muffling signal having a predetermined frequency and level (amplitude) considering the number P of blades is used as the sound source signal. It is stored in the memory 41. This sound source signal is read during operation of the indoor unit and
It is sent to the amplitude adjusting unit 42.

Considering the number P of blades of the cross flow fan 12b,
The standard waveform, the noise waveform, and the total noise value B are represented by the following equation. Standard waveform = As-sin (P-Ns-Fs + φ ₀ ) Noise waveform at primary frequency F ₁ B ₁ = A ₁ -sin (1-P-Na-Fs + φ ₁ ) at secondary frequency F ₂ Noise waveform B ₂ = A ₂ · sin (2 · P · Na · Fs + φ ₂ ) Noise waveform B ₃ = A ₃ · sin (3 · P · Na · Fs + φ ₃ ) n at the _third frequency F ₃ Noise waveform at the next frequency F _n B _n = A _n · sin (n · P · Na · Fs + φ _n ) Then, the amplitude A _n and the phase angle φ _{n are set} so that B = 0.
Is adjusted to obtain a noise canceling signal for canceling noise, that is, a phase opposite to the noise signal.

The other structure is the same as that of the first embodiment. With such a configuration, white noise is added in advance to the noise for muffling emitted from each speaker 32, and the driving noise is effectively canceled by both the noise for muffling and the white noise. Moreover, the frequency and level (amplitude) of the noise for silencing is reduced by the cross flow fan 12
Since the number of blades P of b is taken into consideration, operating noise can be effectively attenuated, and quiet operation can be obtained.

A third embodiment of the present invention will be described.
Here, in the case of using a cross-flow fan (hereinafter, referred to as "random-pitch cross-flow fan") in which the intervals between the blades (blades or blades) provided in a plurality of rows are unevenly arranged, the cross-flow fan 12b is used. Paying attention to the fact that the position of the blades in the circumferential direction of (3) influences the blowing sound, the rotational position sensor 60 is provided as shown in FIG.

The rotational position sensor 60 is the cross flow fan 12b.
To detect the rotational position of the blade, and as shown in FIG. 14, several projections 61 arranged with respect to the position of the blade along the peripheral edge of the axial end of the cross flow fan 12b, and as shown in FIG. It is composed of a U-shaped optical sensor 62 provided at a position sandwiching each protrusion 61. The optical sensor 62 includes a light emitting element 62a and a light receiving element 62b.
By blocking the optical path between a and the light receiving element 62b with the projection 61, a signal (crossing waveform) according to the rotational position of the cross flow fan 12b is output. This output is supplied to each phase adjustment unit 43 of the main control unit 40 as a rotational position signal.

Each phase adjusting section 43 determines the phase of the muffling signal that has passed through the frequency / amplitude adjusting section 42 according to the actual sound level captured by the microphone 34, and further according to the detection result of the rotational position sensor 60. adjust.

The other structure is the same as that of the first embodiment. According to such a configuration, the cross-flow fan 12 having a random pitch is used.
Sound for noise reduction considering the position of the blade in the circumferential direction of b is emitted from each speaker 32, and the driving noise can be attenuated more effectively. Further, since the rotational position of the cross-flow fan 12b having a random pitch is optically detected, it does not become a load on the blower 12.

In the third embodiment, the rotation speed sensor 60 shown in FIG. 16 may be used. That is,
The rotation speed sensor 60 includes several reflecting members 63 arranged along the peripheral edge of the axial end of the cross flow fan 12b and at a predetermined interval, and an optical sensor 64 provided near the reflecting members 63. Composed of. Each reflection member 63 is provided corresponding to each blade position of the cross flow fan 12b, for example.

The optical sensor 64 comprises a light emitting element 64a which emits light toward the reflecting member 63 and a light receiving element 64b which receives the reflected light from the reflecting member 63.
A signal corresponding to the rotational position of the cross-flow fan 12b is output depending on whether or not light is received by b.

A fourth embodiment of the present invention will be described with reference to FIGS. 17 and 18. Here, the front heat exchanger 1
Front drain pan 13 provided along the lower end of 1A
In the rear nose 14 portion, instead of the nose 14, there is provided a cylindrical enclosure 70 in which the cross-sectional shape of both ends is formed in a substantially arc shape. Specifically, the enclosure 70 has a longitudinal shape along the axial direction of the cross flow fan 12b, has an opening facing the ventilation passage 30, and a sound absorbing material 71 is attached to the inner peripheral surface thereof.

Then, one speaker 32 is provided at a substantially central portion in the longitudinal direction of the enclosure 70. Also,
One microphone 3 is provided on the front face portion 2b of the front panel 2.
4 are provided.

The other structure is the same as that of the first embodiment. In this case, the sound for muffling emitted from the speaker 32 is emitted toward the ventilation passage 30 while being transmitted in the fan axial direction by the enclosure 70.

By adopting the enclosure 70, a single speaker can cover the noise reduction process in the fan axis direction. Since the enclosure 70 can be assembled in the unit body 1 as a separate assembly, there is an advantage that the manufacturing becomes easy. Due to the presence of the enclosure 70, it is possible to efficiently produce a low frequency sound as a sound for silencing. Since the sound absorbing material 71 is provided on the inner peripheral surface of the enclosure 70, there is no fear of generating resonance noise.

The enclosure 70 is used in the fourth embodiment.
Although one speaker 32 is provided in the substantially central part of the enclosure, as shown in FIG.
It may be configured so as to face each other at both ends thereof. In this case, the sound inside the enclosure 70 is reflected, so that FIG.
As shown in FIG. 7, the sound for silencing emitted from the speaker 32 has a wavelength of 2 L with respect to the axial length L of the enclosure 70.

[0079]

As described above, in any of the air conditioners of the first to tenth aspects of the present invention, the frequency and level of the standard waveform muffling signal prepared in advance is adjusted according to the number of revolutions of the blower. Moreover, the phase is adjusted according to the level of the detected sound of the microphone, and the adjusted muffling signal is converted into the actual sound by the speaker and then output, so that the microphone for sound source detection is not required. , It is possible to reduce wind noise and howling phenomenon by the microphone, and reliably detect the operation noise generated in the heat exchanger and the blower, and output the opposite phase sound suitable for silencing,
Noise is canceled and quieter driving becomes possible.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a silencer according to a first embodiment.

FIG. 2 is an exploded perspective view showing the configuration of the indoor unit in the first embodiment.

FIG. 3 is a vertical cross-sectional view showing the configuration of the indoor unit in the first embodiment.

FIG. 4 is a waveform diagram of the muffling signal at a low rotational speed in the first embodiment.

FIG. 5 is a waveform diagram of a muffling signal at a high rotation speed in the first embodiment.

FIG. 6 is a waveform diagram of a noise signal.

FIG. 7 is a diagram showing amplitudes of noise signals at respective frequencies F ₁ , F ₂ , ... F _n .

FIG. 8 is a diagram showing a configuration of a modified example of mounting the speaker in the first embodiment.

FIG. 9 is a diagram showing a configuration of a modified example of mounting the microphone in the first embodiment.

FIG. 10 is a perspective view showing a configuration of a modified example of a mounted state of the speaker and the microphone in the first embodiment.

11 is a vertical cross-sectional view of the configuration of FIG.

FIG. 12 is a block diagram showing the configuration of a silencer according to a second embodiment.

FIG. 13 is a block diagram showing the configuration of a silencer according to a third embodiment.

FIG. 14 is a diagram showing a protrusion of a rotation speed sensor in the third embodiment.

FIG. 15 is a diagram showing a protrusion of a rotation speed sensor and an optical sensor in the third embodiment.

FIG. 16 is a perspective view showing a configuration of a modified example of the rotation speed sensor in the third embodiment.

FIG. 17 is an exploded perspective view of the configuration of the indoor unit according to the fourth embodiment.

FIG. 18 is a vertical cross-sectional view showing the configuration of an indoor unit according to the fourth embodiment.

FIG. 19 is a diagram showing a configuration of a modified example of mounting a speaker in the fourth embodiment.

20 is a diagram showing the relationship between the enclosure length and the wavelength of sound in FIG.

FIG. 21 is a perspective view showing an indoor unit and an outdoor unit of each example and a conventional air conditioner.

FIG. 22 is a vertical cross-sectional view showing the configuration of an indoor unit in a conventional air conditioner.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Unit main body, 4 ... Suction port, 9 ... Air outlet, 11 ... Heat exchanger, 12 ... Blower, 12b ... Crossflow fan, 30 ... Ventilation path, 32 ... Speaker, 34 ... Microphone, 40 ...
Main control unit, 41 ... Memory, 42 ... Frequency / amplitude adjusting unit,
43 ... Phase adjustment unit.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location G10K 11/16

Claims (10)

[Claims] 1. A unit body having an inlet and an outlet, and having an air passage from the inlet to the outlet, a heat exchanger and a blower provided in the air passage, and having a predetermined frequency and level. Means for emitting a muffling signal having a standard waveform, a speaker provided at a position facing the ventilation path or in the vicinity of the air outlet, for converting the muffling signal into sound, and a microphone provided at a predetermined position of the unit main body A rotation speed sensor for detecting the rotation speed of the blower, and the frequency and level of the muffling signal are temporarily adjusted according to the detection result of the rotation speed sensor, and the phase of the muffling signal is detected by the detection sound of the microphone. An air conditioner comprising: an adjusting unit that adjusts according to the level of. 2. The air conditioner according to claim 1,
The speaker is provided at a position facing the ventilation path and downstream of the blower, and the microphone is positioned at the position facing the ventilation path.
In addition, the air conditioner is provided not on the upstream side of the speaker but on the downstream side of the speaker. 3. The air conditioner according to claim 1,
An air conditioner characterized in that the speaker is provided at a position facing the ventilation path and downstream of the blower, and the microphone is provided at an outer peripheral portion of the unit body. 4. The air conditioner according to claim 2,
An air conditioner characterized in that a plurality of speakers and a plurality of microphones are provided along an axial direction of a cross flow fan that constitutes a blower. 5. The air conditioner according to claim 1,
An air conditioner characterized in that the adjusting means adjusts the frequency and level of the muffling signal in accordance with the detection result of the rotation speed sensor and in accordance with the number of blades of the cross flow fan that constitutes the blower. 6. The air conditioner according to any one of claims 1 to 5, further comprising means for generating white noise and means for superimposing the white noise on a muffling signal. An air conditioner. 7. A unit main body having a suction port and a blowout port, and having a ventilation path from the suction port to the blowout port; Means for emitting a standard waveform muffling signal having a predetermined frequency and level, a speaker provided at a position facing the ventilation path or in the vicinity of the air outlet, for converting the muffling signal to sound, and the unit main body A microphone provided at a predetermined position, a rotational position sensor that detects the rotational position of the blower, a rotational speed sensor that detects the rotational speed of the blower, and a muffling signal of the muffling signal according to the detection result of the rotational speed sensor. The frequency and level are adjusted once, and the phase of the muffling signal is adjusted according to the phase of the sound detected by the microphone and the detection result of the rotational position sensor. An air conditioner characterized by comprising an adjustment means for settling, the. 8. The air conditioner according to claim 7,
The rotational position sensor is composed of several protrusions arranged along the peripheral edge of the axial end of the blower, and a light emitting element and a light receiving element that face each other with these protrusions sandwiched therebetween, and outputs a rotational position signal. A characteristic air conditioner. 9. The air conditioner according to claim 7,
The rotational position sensor is composed of several reflecting members arranged along the peripheral edge of the axial end of the blower, a light emitting element that irradiates the reflecting members with light, and a light receiving element that receives the reflected light from the reflecting member. And an air conditioner characterized by outputting a rotational position signal. 10. The air conditioner according to any one of claims 1 to 9, which is provided at a position facing a ventilation path of a cylindrical enclosure whose both end portions are formed in a substantially semi-circular cross-section. An air conditioner having a speaker and a sound absorbing material provided in an enclosure.