JP2883228B2 - Microphone mounting structure to molded ceiling material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The structure for mounting a microphone on a molded ceiling material according to the present invention is used for mounting a microphone such as an active noise control device of a vehicle for reducing noise in a vehicle cabin to a headlining. is there.

[0002]

2. Description of the Related Art Conventionally, as an active noise control device of this type, for example, a device described in British Patent Publication No. 2149614 is known. This conventional device is applied to a cabin of an aircraft or a similar closed space, and is located outside the closed space with a plurality of loudspeakers (secondary sound sources) and a plurality of microphones installed in the closed space. Frequency detection means for detecting frequencies f _{0 to} f _n of a single noise source (primary sound source) such as an engine, and control of driving of a plurality of loudspeakers based on detection signals of a plurality of microphones and detection signals of the frequency detection means. And a signal processor.
Then, the signal processor detects detection signals P _n (n = 1, 2,..., M) of a plurality of microphones, that is, a sum of squares of sound pressures: Is used as an evaluation function, adaptive control is performed so as to minimize the evaluation function P. It says that the secondary sound radiated from the loudspeaker and the primary sound transmitted from the noise source interfere with each other to reduce the residual noise at the observation position.

A specific configuration of an active noise control device for a vehicle is shown in FIG. 8 proposed by Lotus, for example. In this active noise control device, a frequency detector A attached to an engine P detects a frequency of vibration generated in the engine P, and a microphone D provided in the vehicle compartment detects noise in the vehicle compartment to detect the frequency. Based on the detection signal of the device A and the detection signal of the microphone D, the controller B performs an operation of the above equation by Fourier transform or LMS algorithm transform of these signals, and outputs a control signal of a control sound. A control sound is generated from a loudspeaker C provided in the vehicle interior according to the signal, and the control sound and residual noise in the vehicle interior interfere to reduce the noise.

In such an active noise control device for a vehicle, it is desirable that the microphone be located near the occupant's ear so as to detect the residual noise heard by the occupant. Or
Alternatively, a plurality of molded ceiling materials (head linings) are attached to a surface (upper surface or rear surface) facing the ceiling.

When the microphone is mounted on the surface of the headlining facing the ceiling, the mounting surface of the microphone D and the surface of the headlining E facing the ceiling are formed on the headlining E as shown in FIG. The sound collecting port J of the microphone D is projected from the through hole K to the indoor side with a double-sided adhesive tape F narrower than the mounting surface, and a plurality of elastic claws H project into the sound collecting port J. The microphone D is fixed by pushing in a so-called push-lock type fixing tool G provided. Here, the reason why the double-sided adhesive tape is used for bonding the microphone and the headlining is that the microphone may be replaced due to deterioration of the characteristics of the microphone. Incidentally, the headlining is usually made of a flexible film because of its texture and sound absorption.

[0006]

However, in the above-described conventional microphone mounting structure, after the microphone is bonded to the surface of the molded ceiling material facing the ceiling, the fixture is pushed into the microphone from the indoor side surface. A pressing force is generated to peel off the adhesive to the headlining, and this pressing force causes a part of the ceiling side of the flexible headlining to be peeled off from itself while being bonded to the microphone and the double-sided adhesive tape, resulting in significant damage. In such a case, the head lining is broken. This is because the area of the double-sided adhesive tape used for bonding the microphone and the headlining is smaller than the mounting surface of the microphone, and in order to secure sufficient holding force,
This is because it is necessary to increase the adhesive strength of the double-sided adhesive tape, and the pressing force acts on the headlining as a large stress within this small adhesive area.

In order to solve this problem, it is conceivable to increase the area of the double-sided adhesive tape or to weaken the adhesive force. In the former case, the holding force between the double-sided adhesive tape and the head lining is considered. Is improved, but the holding force between the double-sided adhesive tape and the microphone is hardly improved, dust adheres to the adhesive surface of the tape protruding from the microphone, and the appearance is poor. In the latter case, for example, the microphone is When the fixture is pushed in after the bonded headlining is fitted to the vehicle, the microphone and the double-sided adhesive tape are peeled off from the headlining due to the pressing force, and the fixture cannot be completely pushed in, and the microphone is securely fixed. May be difficult to perform.

When the microphone D is adhered to one surface of the head lining E, the sound collecting port J is positioned because it is inserted into the through hole K.
Are not positioned, and the direction of the case N may be shifted in the directions of arrows xy in FIG. However, for example, as shown in FIG. 9, when the shape of the fixture G is directional for fitting in the vehicle interior as shown in FIG. 9 and the position of the fixture G inserted into the microphone D is directional, as described above. If the direction of the case N shifts, the direction of the fixture G may also shift. If the direction of the fixing tool G is shifted in this way, it is necessary to re-adhere the microphone D again, which requires a great deal of man-hours and greatly reduces the assembling workability.

Further, as described above, there is a possibility that the microphone D is replaced due to deterioration of its characteristics. At this time, if the entire case N of the microphone D is pulled to be detached from the head lining E, the head lining D is also damaged. There is a possibility that it may drip or break. Therefore, conventionally, when the microphone D is peeled off from the head lining E as described above, the double-sided tape F itself is cut with a thin and strong linear material such as a thread or a piano wire.
However, all mounting surfaces except for the sound collecting port J are double-sided tape F
In the conventional mounting structure, the linear material must be moved from various directions in order to cut the double-sided tape F near the sound collecting port J, and this peeling work takes a lot of time and labor. There was also a problem that would.

The present invention has been developed in view of the above-mentioned problems, and it is possible to securely fix a microphone in a predetermined direction without peeling or breaking a headlining. It is an object of the present invention to provide a microphone mounting structure that can improve exchangeability.

[0011]

According to the first aspect of the present invention, a microphone mounting structure to a molded ceiling material according to the first aspect of the present invention includes a microphone-mounting surface on one surface (a surface facing the ceiling) of a flexible film-shaped molded ceiling material. In the microphone mounting structure for fixing the microphone by pressing a fixing tool into the microphone from the other surface (inside surface of the room) of the molded ceiling material to fix the microphone, the microphone mounting surface and the ceiling of the molded ceiling material are fixed to each other. A reinforcing material or a reinforcing layer wider than a mounting surface of the microphone is provided between the opposite surface.

According to a second aspect of the present invention, in the microphone mounting structure for a molded ceiling material according to claim 2, the reinforcing member has an adhesive surface on the molded ceiling material side and has an area at least twice the mounting surface of the microphone. It is characterized by having a sheet material having. The microphone mounting structure for a molded ceiling material according to claim 3 of the present invention, wherein the reinforcing layer has a surface hardening agent on a surface facing the ceiling of the molded ceiling material in advance at least twice the area of the microphone mounting surface. Is a surface hardened layer obtained by applying and hardening.

[0013]

[0014]

According to a fourth aspect of the present invention, in the structure for mounting a microphone on a molded ceiling material according to a fourth aspect of the present invention, the microphone is for detecting residual noise of an active noise control device.

[0016]

According to the first aspect of the present invention, in the structure for attaching a microphone to a molded ceiling material according to the first aspect of the present invention, a reinforcing member or a reinforcing layer wider than the microphone attaching surface is provided between the microphone attaching surface and the surface of the headlining facing the ceiling. Since, for example, when a reinforcing material is provided, the pressing force for peeling off the microphone generated when the fixing tool is pushed in is dispersed to a small stress by the reinforcing material having a large area and acts on the headlining, When the reinforcing layer is provided, the strength of the head lining in the vicinity of the microphone mounting portion is improved, so that the head lining is less likely to peel or break due to the pressing force.

According to a second aspect of the present invention, in the microphone mounting structure for a molded ceiling material according to the second aspect of the present invention, the reinforcing member has an adhesive surface on the molded ceiling material side and has an area at least twice the mounting surface of the microphone. By having a sheet material having, the sheet material is attached to a mounting portion of the microphone,
It is only necessary to attach a microphone thereon using a double-sided adhesive tape or the like. Further, in a sheet material having an area more than twice as large as the mounting surface, the pressing force generated when the fixing tool is pushed in is dispersed into a small stress, so that the adhesive force per unit area of the sheet material can be reduced. In such a case, for example, when there is a possibility that the microphone is replaced, the sheet material can be easily peeled off from the headlining in a state where the microphone and the sheet material are adhered. Alternatively, if the area of the sheet material is sufficiently large and the adhesive force is sufficiently large, the stress applied to the head lining will be sufficiently small even if the double-sided adhesive tape is peeled off from the sheet material when replacing the microphone, and the head lining will be reduced. No damage.

According to the third aspect of the present invention, in the structure for mounting a microphone on a molded ceiling material according to claim 3, the reinforcing layer is formed on the surface of the molded ceiling material facing the ceiling in an area at least twice as large as the mounting surface of the microphone. Since the surface hardening layer is formed by applying and hardening the surface hardening agent, it is only necessary to bond the microphone on the surface hardened layer with a double-sided adhesive tape or the like. In addition, since the surface hardened layer reinforces the headlining having an area at least twice as large as the mounting surface of the microphone at the mounting portion of the microphone, the stress acting on the headlining even if the microphone is peeled off when replacing the microphone. Are dispersed sufficiently small that they do not damage the headlining.

[0019]

[0020]

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to an active noise control device will be described below with reference to the drawings. FIG. 1 is a configuration diagram showing a configuration of a first embodiment of the present invention, and FIG. 2 is a schematic configuration diagram of an active noise control device. The active noise control device is
As shown in FIG. 2, a loudspeaker C1, which outputs a control sound for canceling the noise in the cabin in the cabin near the lower part of the seat _.
Two sensors C ₂ are mounted, a sensor (not shown) for detecting a reference signal synchronized with the noise is mounted on the chassis, and, for example, eight microphones D ₁ for detecting residual noise in the passenger compartment on the ceiling side. to D ₈ is mounted with a predetermined interval, these loudspeakers C _1, C _2, connected to the controller B which is attached to the rear parcel Q bottom through the sensor and the microphone D ₁ to D ₈ are signal lines M I have.

The controller B is composed of, for example, a microcomputer, and forms a drive signal for canceling noise by adaptively filtering a reference signal from a sensor, and outputs the drive signal to each of the loudspeakers C _{1 and} C ₂ . . At this time,
The filter coefficient of the adaptive filter process, the reference signal detected by the sensor, the spatial transfer functions between each loudspeaker C _1, C ₂ and the microphone D ₁ to D _8, the microphone D ₁ to D ₈ residual noise detecting signal and the previous sequentially updating process in accordance with the LMS algorithm based on the filter coefficients, by interference and noise control sound and the passenger compartment that is output from the loudspeaker C _1, C _2, microphone D ₁ to D ₈
Is controlled so that the residual noise detection signal of the above becomes substantially zero.

Then, each microphone D₁~ D₈Is
As shown in FIG. 1, for example, a case body 10 made of synthetic resin
And a sound collecting port 11 formed on the lower surface thereof, and a case body 10
And a connector portion 12 formed on the right side of the
Headlining E as a flexible film-shaped molded ceiling material
Mounted on That is, the headlining E
Insert the sound collection port 11 into the microphone mounting position
A hole 13 is formed, and the insertion hole 1 is
3 and an adhesive layer only on the lower surface.
The under sheet 1 having
And a through hole 15 through which the sound collection port 11 is inserted is formed on the upper surface of the
Through a double-sided adhesive tape F having a predetermined adhesive strength.
Clophon D₁~ D₈Is inserted into the sound collecting port 11
It faces the lower side of the head lining E through 3 and 14.
The sound collecting port 11 is attached to the sound collecting port 11 from the indoor side.
A so-called push lock type having a cap portion 16 having a diameter larger than 11
Of the microphone D is inserted.₁~ D ₈But
It is firmly attached to the headlining E.

Here, the area of the undersheet ₁ is selected to be at least twice as large as the area of the mounting surface in the microphones D _{1 to} D ₈ , and the adhesive strength of the adhesive layer is determined by the adhesive strength of the double-sided adhesive tape F. The adhesive strength is selected to be about half the force. And the microphones D _1-
Attachment to the head lining E of D _8, first the lower surface of the mounting surface of the microphone D ₁ to D _8, the pre-sided adhesive tape F with previously adhered peel off the release paper on the upper surface side,
The undersheet 1 is bonded to the upper surface of the head lining E so that the adhesive layer is on the lower side, and the insertion hole 14 matches the insertion hole 13 of the head lining E. The microphone D ₁ to D the lower surface side of the release paper of double-sided adhesive tape F adhered after peeling the _8, the microphone D ₁ to D ₈ of the insertion hole 14 and the head lining of the under sheet 1 and the sound collecting port 11 adhered to the upper surface of the under sheet 1 while inserted into the insertion hole 13 of the E, and a harness L of the signal line M to the connector portion 12 is connected to the microphone D ₁ to D ₈ are fitted in the bonded wear state, The microphones D _{1 to} D ₈ are temporarily fixed to the headlining E. After that, the fixtures G are inserted into the sound collecting ports 11 from the lower surface side of the head lining E, so that the microphones D _{1 to} D _{8 are} inserted.
And clamped the head lining E and under the seat 1 between the lower surface of the the upper surface of the cap portion 16 of the fastener G, is firmly fixed to the head lining E microphone D ₁ to D _8.

As described above, according to the first embodiment, the undersheet ₁ having an area about twice as large as the mounting surface of the microphones D _{1 to} D ₈ is bonded to the microphone mounting surface of the headlining E, and Since the microphones D _{1 to} D ₈ are bonded and temporarily fixed on the base ₁ via a double-sided adhesive tape F, the fixture G is fitted to the sound collecting port 11 from the lower surface side of the head lining E in this temporarily fixed state. Even when a large pressing force is applied to separate the microphones D _{1 to} D ₈ upward during the joining, the pressing force can be dispersed by the under sheet 1 and the stress applied to the head lining E is reduced. Thus, it is possible to reliably prevent the head lining E from being damaged.

Further, the microphones D _{1 to} D ₈ and the under sheet 1 are connected to the double-sided adhesive tape F having a high adhesive strength.
The adhesive force per unit area of the undersheet 1 is smaller than the adhesive force of the double-sided adhesive tape F by the amount that the stress applied to the undersheet 1 is reduced. For example, when the noise suppression effect of the active noise control device is reduced due to deterioration of the microphone characteristics due to long-term use and it becomes necessary to replace the microphones, the microphones D _{1 to} D ₈ may be replaced with double-sided adhesive tape. F, while the under sheet 1 is adhered to the head lining E
By exfoliating the microphone 1, the microphone 1 can be easily replaced without damaging the headlining E.

In the above embodiment, the undersheet was used as the reinforcing material, and the microphone was bonded to the undersheet via the double-sided adhesive tape. However, the microphone may be directly bonded to the undersheet using, for example, an adhesive. In this case, the microphone may be replaced with the under sheet. Further, the reinforcing material is not limited to the sheet-like material as in the embodiment, but may be, for example, a plate-like material or a lump-like material.

FIG. 3 shows an application to an active noise control device of a vehicle.
Of the microphone mounting structure to the molded ceiling material of the present invention
This is a second embodiment, which is reinforced at the microphone mounting portion.
A layer is formed. This reinforcing layer is, for example,
Agent to microphone D₁~ D₈Around the mounting site (front
As described above, the area of the microphone
Area) on the top surface facing the ceiling of the headlining E
Applying a surface hardener and curing the surface hardened layer 2
It consists of. After the hardening of the surface hardener, the surface hardness
Holes 13 are formed in the activated layer 2 and the head lining E,
Surface hardened layer 2 and microphone D ₁~ D₈Mounting surface and
With a double-sided tape F and the double-sided tape
F, reinforcement layer 2 and head lining E
Clophon D₁~ D₈Through the sound collecting port 11
From inside of the headlining E inside the J
Microphone D₁
~ D₈Is fixed.

When a reinforcing layer is previously formed on the head lining as in the second embodiment, a double-sided adhesive tape is used to hold the microphone so that it does not peel off against the pressing force when the fixing tool G is pressed. The adhesive strength must be sufficiently strong. However, if the strength of the reinforcing layer is sufficient, even if the adhesive strength of the double-sided tape is strong, the double-sided tape can be peeled from the reinforcing layer without damaging the headlining.

FIG. 4 shows a third embodiment of a microphone mounting structure on a molded ceiling material according to the present invention applied to a vehicle active noise control apparatus, in which a microphone mounting position is marked. In this embodiment, for fitting the vehicle interior, for example, as shown in FIG. 9, the cap portion 16 of the fixture G has a direction, and the sound collecting port 11 and the fixture G
There is also a directionality in the insertion position relationship with. Therefore, the case bodies 10 of the microphones D _{1 to} D ₈ need to be adhered to predetermined positions on the upper surface of the headlining E in a predetermined direction.

An insertion hole 13 for inserting the sound collecting port 11 is formed at a predetermined position in the microphone mounting portion of the head lining E, similarly to the first and second embodiments.
In addition, as shown in FIG. 4B, the microphone mounting portion of the head lining E has a U-shaped marking on a portion of the rectangular parallelepiped case body 10 to which two corner portions 17 far from the sound collecting port 11 are to be bonded. 3 are formed in advance.

The marking 3 is formed at the same time by embossing at the time of manufacturing the head lining E which is a molded ceiling material, and is formed simultaneously with the insertion hole 13 formed at the same time. Accurately located. Therefore, the sound collecting port 11 is inserted into the insertion hole 15 of the double-sided tape F, the upper surface of the double-sided tape F is adhered to the mounting surface of the microphones D _{1 to} D ₈ , and the sound collecting port 11 is inserted through the head lining E. The lower surfaces of the double-sided tape F are adhered to the upper surface of the head lining E such that the microphones D _{1 to} D ₈ are inserted into the holes 13 and the corners 17 are positioned inside the markings 3. Glued in the direction of

When the marking 3 is formed by recessing the head lining E by embossing, care must be taken so that the strength of the head lining E in the vicinity of the marking 3 does not decrease, as in this embodiment. Marking 3 of corner 17 of case body 10 far from sound collection opening 11
, The deviation of the directions of the microphones D _{1 to} D ₈ can be minimized even if the marking 3 itself is small.

The marking 3 is not limited to the above-described shape and position, but may be, for example, a shape as shown in FIGS. Of these, the one shown in FIG. 5A indicates the end of the long side of the rectangular parallelepiped case body 10 far from the sound collection port 11, and the one shown in FIG. This indicates the short side 19 far from the sound collection port 11. Further, a marking may be provided at a position on the upper surface of the case body 10 far from the sound collection port 11, and a marking may be provided at a position of the head lining E facing the marking of the case body 10. Further, in this embodiment, the marking is formed by recessing the head lining by embossing. However, the marking may be provided by, for example, protruding the head lining or by printing such as inking.

When the third embodiment is used in combination with the first and second embodiments, for example, the undersheet and the surface hardener may be made transparent. FIG. 6 shows a fourth embodiment in which the microphone mounting structure of the present invention is applied to an active noise control device for a vehicle, in which a step is formed on the mounting surface of the microphone.

As shown in FIG. 6A, a step portion 4 which is one step higher than the mounting surface 20 is formed on the mounting surface of the rectangular microphones D _{1 to} D ₈ from the central portion in the longitudinal direction to the sound collecting port 11 side. . The step portion 4 is formed by integrally forming a lattice-shaped ridge with the case body 10, and a boundary line 21 with the mounting surface 20.
Is designed to be linear. Then, to the head lining E, without applying the double-sided tape F to the step portion 4,
Microphones D _{1 to} D ₈ are adhered by attaching one surface of double-sided tape F only to mounting surface 20 and attaching the other surface of double-sided tape F.

Although the microphone mounting structure does not greatly improve the assembling workability, the workability at the time of replacing the microphone due to deterioration of the microphone characteristics is improved. Normally, when replacing the microphone, the double-sided tape F is torn by a thin and strong linear material Q such as a thread or a piano wire, and the microphones D _{1 to} D ₈ are torn.
At this time, as shown in FIG. 6B, when the linear material Q is pressed against the double-sided tape F from the side opposite to the step portion 4 and the double-sided tape F is torn in the direction of the arrow y in FIG. The linear material Q linearly contacts the boundary line 21 and tears the double-sided tape F, that is, the microphones D _{1 to} D _8.
It is perceived that the exfoliation has been completed. With this microphone mounting structure, there is no need to tear the double-sided tape F near the sound collecting port 11 with the linear material Q from various directions as in the related art.
Workability is greatly improved.

The shape of the step portion 4 is not limited to the above, and the same effect as described above can be obtained even if the boundary line with the mounting surface is an arc having a small curvature. The above four embodiments are all applied to an active noise control device for a vehicle, but the application of the microphone mounting structure of the present invention is not limited to this.

[0039]

As described above, a reinforcing member or a reinforcing layer wider than the microphone mounting surface is provided between the microphone mounting surface and the ceiling side surface of the headlining, so that the fixing tool is pushed into the microphone. The pressing force generated to separate the microphone is dispersed in the reinforcing material or the reinforcing layer and acts as a small stress on the head lining, and the strength near the mounting portion of the microphone is also improved. As a result, the head lining is less likely to peel or break. For this reason, since it is not necessary to weaken the adhesive force with the microphone, it is possible to securely press the fixing tool and securely fix the microphone. In addition, since the adhesive strength between the reinforcing material or the reinforcing layer and the headlining can be weakened, it is easy to peel them off directly, and conversely, the area of the reinforcing material or the reinforcing layer is made sufficiently large to bond them to the headlining. When the force is increased, the reinforcing material or the reinforcing layer is firmly held, the headlining is strengthened, and the microphone is easily separated from the reinforcing material or the reinforcing layer, so that the exchangeability of the microphone is dramatically improved.

Further, if the reinforcing material is a sheet material having an adhesive surface on the molded ceiling material side and having an area at least twice the mounting surface of the microphone, the sheet material is attached to the microphone mounting portion, The mounting workability is not impaired since the microphone only needs to be adhered thereon with a double-sided adhesive tape or the like. Further, in a sheet material having an area more than twice as large as the mounting surface, the pressing force generated when the fixing tool is pushed in is dispersed into a small stress, so that the adhesive force per unit area of the sheet material can be reduced. If so, for example, if there is a possibility of replacing the microphone, with the microphone and the sheet material adhered,
The sheet material can be easily peeled off from the headlining. Alternatively, if the area of the sheet material is sufficiently large and the adhesive force is sufficiently large, the stress applied to the head lining will be sufficiently small even if the double-sided tape is peeled off from the sheet material at the time of replacing the microphone. The effect of being able to peel without damage is exhibited.

Further, if the reinforcing layer is constituted by a surface hardening layer which is previously applied with a surface hardening agent on the ceiling side surface of the molded ceiling material in an area at least twice as large as the mounting surface of the microphone, and hardened, It is only necessary to bond the microphone on the top with a double-sided tape or the like, and the mounting workability is good. Also,
Since the surface hardening agent reinforces the headlining having an area at least twice as large as the mounting surface of the microphone at the mounting portion of the microphone, the stress acting on the headlining is sufficient even if the microphone is replaced when the microphone is replaced. The microphone and the double-sided tape can be peeled off without damaging the headlining.

[0042]

[0043]

[Brief description of the drawings]

FIGS. 1A and 1B show a first embodiment of a microphone mounting structure to a molded ceiling material according to the present invention, wherein FIG.
(B) is a longitudinal sectional view after attachment.

FIG. 2 is a schematic configuration diagram of an active noise control device to which the microphone mounting structure of FIG. 1 is applied.

FIG. 3 is a perspective view showing a second embodiment of the structure for mounting a microphone on a molded ceiling material according to the present invention, in a mounted state.

4A and 4B show a third embodiment of the microphone mounting structure on a molded ceiling material according to the present invention, wherein FIG.
(B) is a plan view after attachment.

FIG. 5 is a plan view showing another marking of the third embodiment.

6A and 6B show a fourth embodiment of the microphone mounting structure to a molded ceiling material according to the present invention, wherein FIG.
(B) is a longitudinal sectional view after attachment.

7A and 7B show an example of a conventional microphone mounting structure on a molded ceiling material, wherein FIG. 7A is a perspective view of a mounted state, and FIG. 7B is a longitudinal sectional view after mounting.

FIG. 8 is a basic configuration diagram of a conventional active noise control device.

FIGS. 9A and 9B show an example of a directional fixture, wherein FIG. 9A is a plan view and FIG. 9B is a partial cross-sectional front view.

FIG. 10 is a plan view showing a state in which a directional fixture is attached to a directional microphone.

[Explanation of symbols]

 1 is an undersheet (reinforcing material) 2 is a reinforcing layer 3 is a marking 4 is a stepped portion 10 is a case body 11 is a sound collection hole 13 is an insertion hole 20 is a mounting surface A is a frequency detector B is a controller C is a speaker D is a microphone E is a headlining (molded ceiling material) F is a double-sided tape G is a fixture

Continuation of the front page (72) Inventor Kenji Sato 2520 Oaza Takabata, Katsuta City, Ibaraki Prefecture Inside the Automotive Equipment Division of Hitachi, Ltd. (56) References JP-A-61-48210 (JP, A) 32540 (JP, U) (58) Field surveyed (Int. Cl. ⁶ , DB name) B60R 11/02 B60R 13/02 H04R 1/02 108 B60Q 3/02

Claims (4)

(57) [Claims] 1. A microphone mounting structure on a molded ceiling material, wherein a microphone mounting surface is bonded to one surface of the molded ceiling material, and a fixture is pressed into the microphone from the other surface of the molded ceiling material to fix the microphone. A structure for mounting a microphone to a molded ceiling material, wherein a reinforcing material or a reinforcing layer wider than the microphone mounting surface is provided between the microphone mounting surface and one surface of the molded ceiling material. 2. The molded ceiling according to claim 1, wherein the reinforcing material is a sheet material having an adhesive surface on a molded ceiling material side and having an area at least twice as large as a mounting surface of the microphone. Microphone attachment structure to material. 3. The hardening layer according to claim 1, wherein the reinforcing layer is a hardened surface layer formed by applying a hardening agent to one surface of a molded ceiling material in an area at least twice the mounting surface of the microphone. 2. A microphone mounting structure to the molded ceiling material according to 1. 4. A pre-Symbol microphone claim 1, characterized in that is used for the residual noise detecting an active noise control system
4. A microphone mounting structure on a molded ceiling material according to any one of claims 3 to 3.