JPH05257484A - Silencer - Google Patents

Abstract

PURPOSE:To obtain a silencer capable of eliminating noises such as machine noises or working noises propagated from the building of a plant to a residential area through a sound insulating wall and to improve the noise environment of the residential area due to noises generated from the building of the plant. CONSTITUTION:An electronic silencer 10 is arranged on the sound insulating wall dividing the yard of the plant building from the residential area. Namely a sensor microphone 18 is arranged on the plant building side of the wall and a speaker 20 and an error microphone 22 are set up on the upper end part of the wall. A controller 24 forms a driving signal for generating an additive sound having reverse phase and the same sound pressure to a noise produced from the plant building from the speaker 20 based upon a signal indicating the noise detected by the microphones 18, 22. The driving signal is outputted to the speaker 20. Thereby the noise from the plant building interfares with the sound wave of the additive sound generated from the speaker on the position of the error microphone 22 in the vicinity of the upper end part of the wall and the noise is eliminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a muffler, and more particularly to a muffler that muffles noise such as mechanical noise and work noise propagating to a residential area from a factory building adjacent to the residential area.

[0002]

2. Description of the Related Art Conventionally, from the viewpoint of improving the noise environment in a residential area, a factory adjacent to a residential area has taken soundproof measures so that mechanical noise and work noise from the factory building do not propagate to the residential area. .. Soundproofing measures for factory buildings are generally performed by installing soundproof walls around the factory buildings. Inside this soundproof wall, a sound insulating material on the factory side and a sound absorbing material on the residential area side are vertically arranged side by side to block the noise from the factory building with the sound insulating material and the noise leaked from the sound insulating material. The noise is absorbed by the sound absorbing material.

[0003]

However, in the conventional sound deadening equipment using only the soundproof wall, the noise in the high frequency range of the noise can be absorbed by the sound absorbing material of the soundproof wall, but the noise in the low frequency range can be absorbed. It is not effective, and there is a drawback that the noise in the low frequency range wraps around the residential area from the upper end of the noise barrier and propagates to the residential area. Therefore, it is not effective in improving the noise environment in the residential area.

The present invention has been made in view of the above circumstances, and eliminates noise such as mechanical noise and work noise propagating to a residential area from a factory building around a soundproof wall to reduce noise from the factory building. An object of the present invention is to provide a silencer capable of improving the noise environment in a residential area caused by the noise reduction device.

[0005]

In order to achieve the above object, the present invention silences noise such as mechanical noise and work noise propagating to a residential area from a factory building standing adjacent to the residential area. In the sound deadening device, the noise information detecting means for detecting the noise radiated from the factory building, which is installed on the factory building side with respect to the soundproof wall separating the residential area and the factory building, and the upper end of the soundproof wall Installed on the upper part of the soundproof wall and radiated from the electromechanical conversion means, which is installed in the section and emits an additional sound having the same sound pressure in antiphase with respect to the noise from the factory building. Based on the signals from the mechanical-electrical conversion means for detecting the noise after the additional sound and the noise have interfered with each other in the vicinity of the upper end of the soundproof wall and converting it into an electric signal, and the noise information detection means and the mechanical-electrical conversion means. , The noise radiated from the factory building Characterized by comprising the additional sound and the same sound pressure with inverted phase, and a control means for generating a drive signal for generating from said electromechanical transducer means to.

[0006]

According to the present invention, the electronic noise suppression system is installed on the soundproof wall separating the factory building and the residential area, so that mechanical noise, work noise, etc. that propagate around the soundproof wall from the factory building to the residential area. The noise in the housing, especially in the low frequency range, was silenced to improve the noise environment in the residential area. That is, the noise information detection means is installed on the factory building side with respect to the soundproof wall, and the electromechanical conversion means and the mechanical-electrical conversion means are installed on the upper end portion of the soundproof wall. Then, based on the signal indicating the noise detected by the noise information detecting means and the mechanical-electrical converting means by the control means, an additional sound having an opposite phase and the same sound pressure to the noise emitted from the factory building is added to the electric machine. A drive signal to be generated from the conversion means is created. Then, the drive signal is output to the electromechanical conversion means. As a result, in the vicinity of the upper end of the noise barrier, the noise from the factory building is silenced by the sound wave interference at the position of the electromechanical converting means due to the additional sound from the electromechanical converting means. Does not propagate. This can improve the noise environment in the residential area caused by the noise from the factory building.

By mounting the noise information detecting means on the inside of the roof of the factory building, erroneous detection due to rain can be prevented, and an interference member for interfering wind with the peripheral portion of the sound absorbing portion of the noise information detecting means is provided. By attaching it, erroneous detection due to wind noise can be prevented. Further, the mechanical-electrical converting means is fixed to a tip end portion of a substantially U-shaped arm member having one end fixed to an upper end portion of the soundproof wall so that the sound absorbing portion faces downward, and the mechanical-electrical converting means is provided with an umbrella member. By installing it, you can prevent false detection due to rain, and
By installing an interference member that interferes with the wind around the sound absorbing portion, erroneous detection due to wind noise can be prevented. As a result, the noise from the factory building can be surely silenced.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A silencer according to the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a silencer 10 according to the present invention.
However, an example in which it is installed on the soundproof wall 16 that separates the site 12 side of the factory building from the residential area 14 side is shown. As shown in FIG. 2, the electronic silencer 10 includes noise information detecting means (hereinafter,
Sensor microphone 18, electromechanical conversion means (hereinafter,
It is composed of a speaker 20, a mechanical-electrical conversion unit (hereinafter, error microphone) 22, and a control unit (hereinafter, controller) 24.

The sensor microphone 18 is installed on the site 12 side of the factory building of the soundproof wall 16, and its sound absorbing portion 18a is provided at a predetermined height with respect to the factory building 26 shown in FIG. Noise such as machine noise and work noise generated in the factory building 26 is detected by the sensor microphone 18, and a signal indicating the noise is input from the sensor microphone 18 to the controller 24 via the cable 28.

As shown in FIG. 2, the speaker 20 is embedded in the upper end of the soundproof wall 16 and its additional sound generating surface 20a faces upward. In addition, the speaker 20
Are connected to the controller 24 via a cable 30. The error microphone 22 is installed at the upper end of the soundproof wall 16, and the sound absorbing surface 22a is provided slightly above the upper end of the soundproof wall 16. Noise near the upper end of the soundproof wall 16 (noise in the low frequency range) is detected by the error microphone 22, and a signal indicating the noise is input to the controller 24 via the cable 32.

Inside the soundproof wall 16, a sound insulating material 34 on the side of the factory building 26 and a sound absorbing material 36 on the side of the residential area 14 are arranged vertically in parallel. Next, the controller 24
The silencing control method by will be described. Controller 2
The information indicating the noise from the factory building 26 detected by the sensor microphone 18 and the information indicating the noise detected by the error microphone 22 are input to 4. Then, the controller 24 creates a drive signal for causing the speaker 20 to generate an additional sound having an opposite phase and the same sound pressure with respect to the noise from the factory building 26, based on these pieces of information. And
The controller 24 outputs the drive signal to the speaker 20.

As a result, in the vicinity of the upper end of the soundproof wall 16, noise in the low frequency range from the factory building 16 that wraps around the upper end of the soundproof wall 16 toward the residential area 14 is emitted from the speaker 20 at the position of the error microphone 22. The sound is interfering with the additional sound and is muted. Further, the noise in the high frequency range from the factory building 26 is absorbed by the sound absorbing material 36 of the soundproof wall 16 and silenced. As a result, noise from the factory building 26 does not propagate to the residential area 14. Therefore, the noise environment of the residential area 14 caused by the noise from the factory building 26 can be significantly improved by installing the electronic silencer 10 in the soundproof wall 16 and its vicinity.

FIG. 3 shows another embodiment relating to the installation position of the silencer according to the present invention. According to FIG. 3, the sensor microphone 18 is mounted inside the roof 27 of the factory building 26. As a result, the sensor microphone 18 is prevented from being erroneously detected due to the adhesion of rain. In addition, the sensor microphone 18
A sound absorbing material 38 that interferes with the wind is attached to the back surface of the roof 27 around the sound absorbing portion 18a. This prevents the sensor microphone 18 from being erroneously detected by the wind noise.

Further, the error microphone 22 has a substantially U-shaped hook arm 4 having one end fixed to the upper end of the soundproof wall 16.
No. 0 is fixed to the tip of the sound absorbing part 2 as shown in FIG.
2 is turned down. An umbrella 42 is attached so as to surround the sound absorbing portion 22a. As a result, the error microphone 22 prevents rain from adhering to the error microphone 22 and thus prevents erroneous detection due to rain. Further, a sound absorbing material 44 that interferes with the wind is attached to the inner side of the umbrella 42 at the peripheral portion of the sound absorbing portion 22a. As a result, the error microphone 22
Erroneous detection due to wind noise is prevented.

On the other hand, the speaker 20 is, as shown in FIG.
The additional sound generation surface 20a is installed toward the error microphone 22 and is installed in the rain avoidance box 46. As a result, the speaker 20 is prevented from being adversely affected by the adhesion of rain. In this way, the sensor microphone 18 and the error microphone 22 are attached so as not to be affected by wind and rain, and the speaker 20 is attached so as not to be affected by rain, so that the factory building 26 The noise from can be surely silenced.

[0016]

As described above, according to the silencer of the present invention, the electronic silencer including the noise information detecting means, the electromechanical converting means, the electromechanical converting means, and the controlling means is installed in the factory building and the residential area. It is installed on the soundproof wall that separates the noise from the factory building to muffle the noise such as mechanical noise and work noise that propagates to the residential area from the factory building. The environment can be improved.

By mounting the noise information detecting means on the inside of the roof of the factory building, erroneous detection due to rain can be prevented, and an interference member for interfering wind with the peripheral portion of the sound absorbing portion of the noise information detecting means is provided. By attaching it, erroneous detection due to wind noise can be prevented. Further, the mechanical-electrical converting means is fixed to a tip end portion of a substantially U-shaped arm member having one end fixed to an upper end portion of the soundproof wall so that the sound absorbing portion faces downward, and the mechanical-electrical converting means is provided with an umbrella member. By installing it, you can prevent false detection due to rain, and
By installing an interference member that interferes with the wind around the sound absorbing portion, erroneous detection due to wind noise can be prevented. As a result, the noise from the factory building can be surely silenced.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an installation environment of a silencer according to the present invention.

FIG. 2 is a sectional view showing the first embodiment of the installation position of the silencer according to the present invention.

FIG. 3 is a cross-sectional view showing a second embodiment of the installation position of the silencer according to the present invention.

FIG. 4 is a sectional view showing how the error microphone shown in FIG. 3 is attached.

[Explanation of symbols]

 10 ... Electronic silencer 16 ... Sound barrier 18 ... Sensor microphone 20 ... Speaker 22 ... Error microphone 24 ... Controller

Claims (2)

[Claims] 1. A silencer for silencing noise such as mechanical noise and work noise propagating to a residential area from a factory building standing adjacent to the residential area, which separates the residential area from the factory building. Noise information detection means installed on the factory building side with respect to the soundproof wall to detect the noise radiated from the factory building, and installed at the upper end of the soundproof wall in the opposite phase to the noise from the factory building. Further, the electromechanical conversion means for radiating the additional sound of the same sound pressure is installed at the upper end of the soundproof wall, and the additional sound and the noise emitted from the electromechanical conversion means interfere with each other near the upper end of the soundproof wall. Based on signals from the noise information detection means and the mechanical-electrical conversion means, the mechanical-electrical conversion means for detecting the subsequent noise and converting it into an electric signal, and the same sound with the opposite phase to the noise radiated from the factory building. The additional sound of pressure is Silencing apparatus characterized by comprising a control means for creating a driving signal for generating the mechanical conversion means. 2. The noise information detecting means is mounted inside a roof of a factory building to prevent erroneous detection due to rain, and winds around the sound absorbing portion to prevent erroneous detection due to wind noise. An interfering member for interfering with the electromechanical conversion means is attached, and the mechanical-electrical converting means is fixed to the tip of a substantially U-shaped arm member whose one end is fixed to the upper end of the soundproof wall, and the sound absorbing part is installed downward. In addition, an umbrella member is attached to prevent erroneous detection due to rain, and an interference member for interfering wind with the peripheral portion of the sound absorbing portion is attached to prevent erroneous detection due to wind noise. The silencer according to claim 1.