JP4524972B2 - Soundproof structure of microphone - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a soundproof structure for a microphone.
[0002]
[Prior art]
Conventionally, as shown in FIG. 7, an automobile hands-free device has been realized. The vehicle hands-free device includes a mobile phone 1, an electronic control device 2, a microphone 3, and a speaker 4.
[0003]
In this device, when the mobile phone 1 receives a reception signal using radio waves as a medium, the electronic control unit 2 causes the speaker 4 to output a transmission voice based on the reception signal. Further, when the microphone 3 receives the transmitted voice and outputs a transmitted signal, the electronic control device 2 outputs the transmitted signal to the mobile phone. Along with this, the cellular phone transmits a transmission signal using radio waves as a medium.
[0004]
Here, by arranging the microphone 3 together with the speaker 4 on the driver's seat side, the driver can perform a hands-free call without holding the mobile phone 1.
[0005]
[Problems to be solved by the invention]
By the way, when the driver makes a hands-free call, the microphone 3 is disposed in the vicinity of the support portion of the steering device, so that the driver's voice can be efficiently received. However, when an accident such as a collision occurs and the airbag device built in the steering device in the driver's seat is activated, the airbag covers the steering device.
[0006]
Therefore, since the microphone 3 is covered with the air bag together with the steering device, the microphone 3 cannot receive the driver's transmitted voice satisfactorily. Thus, when an accident occurs, the microphone 3 does not perform its function.
[0007]
In particular, when the microphone 3 is used to make an emergency call in the event of an accident as in the Mayday system, the microphone 3 receives not only the driver but also the voices of the front passenger and the rear passenger. It will be necessary.
[0008]
Here, it is also conceivable to arrange the microphone 3 between the outer plate and the inner plate at the center of the ceiling (roof) in the vehicle interior. However, in a narrow space sandwiched between the outer plate and the inner plate, vehicle exterior noise, traveling vibration, etc. are transmitted through the outer plate, causing resonance in the narrow space. Therefore, since a large noise is transmitted to the microphone 3, the S / N ratio of the received signal of the microphone 3 is deteriorated.
[0009]
On the other hand, if the microphone 3 is disposed so as to protrude toward the vehicle interior side of the inner plate, it is possible to prevent external noise and traveling vibration from being transmitted to the microphone 3, but this is not preferable in terms of design.
[0010]
For this reason, there is a demand for a soundproof structure for a microphone that can provide a good S / N ratio even when the microphone 3 is placed in a space with a poor noise environment, such as a narrow space sandwiched between an outer plate and an inner plate. The
[0011]
In view of the above points, an object of the present invention is to provide a soundproof structure for a microphone that can provide a good S / N ratio.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a soundproof structure for a microphone that is attached to a vehicle, and has a sound opening (12c) that allows a transmitted sound from the inside of the vehicle to pass therethrough. The design plate (12) forming the design surface in the vehicle interior, the microphone element (50) arranged on the vehicle outer side than the design plate and converting the transmitted voice into an electric signal, and the vehicle outside the design plate And an inner case (40) that is formed from a soundproof member and is disposed so as to cover the microphone element, and that has an opening (41) that transmits the transmitted voice from the voice opening to the microphone element. It is characterized by.
[0013]
Thereby, even if it arrange | positions a microphone element on the vehicle outer side rather than a design board, it arrange | positions so that a microphone element may be covered while it arrange | positions as a soundproof member on the vehicle outer side rather than a design board. Therefore, noise can be prevented from being transmitted to the microphone element from other than the opening. For this reason, the S / N ratio can be improved without affecting the design of the vehicle.
[0014]
Further, in the invention according to claim 1, formed from a soundproof member, characterized by having a soundproof member outer cover disposed to cover except for the opening (30). Thereby, it can prevent reliably that noise is transmitted to a microphone element from other than the opening part of an inner side case .
[0015]
Further, the invention according to claim 1 is characterized in that the outer cover is formed of an elastic member, and has a pressing member (20) that presses the outer cover toward the design plate and elastically deforms it.
[0016]
Thereby, since the clearance gap between a design board and an outer side cover can be eliminated, the adhesiveness of an outer side cover can be improved with respect to a design board. Therefore, the soundproofing effect of the outer soundproofing member can be enhanced.
[0017]
The invention according to claim 2 is characterized in that a void (D) is formed between the inner case and the outer cover , and the void is located on the pressing member side.
[0018]
Thereby, even if a vibration is transmitted from the pressing member to the outer cover , this vibration can be prevented from being transmitted to the inner case by the space. Accordingly, it is possible to prevent vibration from the pressing member from being transmitted to the microphone element through the outer cover through the inner case .
[0019]
In the invention described in claim 1 , the outer cover is provided with a projection (31), and the pressing member has a fitting portion (21) that fits into the projection. . Thereby, the position of the outer cover with respect to the pressing member can be favorably held.
[0020]
In the third aspect of the present invention, the electric wiring (51) for outputting the electric signal converted by the microphone element is provided, and the first through hole (45) penetrating the electric wiring is provided in the inner case. The projection of the outer cover is provided with a second through hole (31a) that penetrates through the electrical wiring penetrating from the first through hole.
[0021]
Incidentally, the reference numerals in parentheses of each means described above are an example showing the correspondence with specific means described in an embodiment described later.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
1 to 4 show an embodiment of an overhead module M to which an automobile microphone soundproof structure according to the present invention is applied.
[0023]
FIG. 1 is a perspective view showing the overhead module M, and FIG. 2 is a cross-sectional view showing the overhead module M. FIG. 3 is a perspective view of the overhead module M viewed from the vehicle interior side, and FIG. 4 is a perspective view of the overhead module M viewed from the outer plate side.
[0024]
As shown in FIG. 1, the overhead module M is disposed in a roof portion (roof) of an automobile, and the overhead module M is located at a substantially central portion in the left-right direction of the vehicle on the front seat side of the vehicle. .
[0025]
As shown in FIG. 2, the overhead module M has a substantially rectangular case 10, and the case 10 is fitted into the outer plate 200 side in the opening 100 a of the inner plate 100.
[0026]
Here, the case 10 includes a case main body 11 and an exposed plate 12, and the case main body 11 is disposed between the inner plate 100 and the outer plate 200. The exposed plate 12 is disposed below the case body 11, and the exposed plate 12 is exposed to the vehicle interior side of the inner plate 10.
[0027]
As shown in FIG. 3, a sound hole 12 c is formed on the passenger seat side of the exposed plate 12, and the sound hole 12 c transmits a received voice from the passenger compartment to a microphone M described later. In FIG. 3, reference numeral 300 indicates a map lamp, and reference numeral 400 indicates a sun visor.
[0028]
Further, as shown in FIG. 4, the overhead module M includes a microphone R and a metal bracket 20, and the microphone R is disposed to face the exposed plate 12.
[0029]
The microphone R is fixed to the case main body 11 via the bracket 20, and one end of the bracket 20 is fastened to the back surface 11 a of the case main body 11 with a screw 500. As a result, the microphone R is pressed toward the exposed plate 12 side.
[0030]
Here, the exposed plate 12 is provided with projecting portions 12a and 12b projecting toward the outer plate 200, and the projecting portions 12a and 12b are each a fitting portion of the outer cover of the microphone R, as will be described later. To fit.
[0031]
Next, the structure of the microphone R will be described with reference to FIGS. 5 is a top view of the microphone R as viewed from the outer plate 200 side, and FIG. 6 is a cross-sectional view taken along the line AA in FIG.
[0032]
As shown in FIG. 5, the microphone R includes an outer cover 30 made of an elastic material such as rubber, and the outer cover 30 serves as a soundproof member. Further, the outer cover 30 has a protruding portion 31 protruding toward the outer plate 200 side. The protruding portion 31 is fitted to the fitting portion 21 of the bracket 20 to hold the position of the microphone R.
[0033]
Further, the outer cover 30 is provided with fitting portions 32a and 32b, and the fitting portions 32a and 32b are fitted into the projections 12a and 12b of the exposed plate 12 described above, respectively. Thereby, the position of the outer cover 30 with respect to the exposed plate 12 can be maintained.
[0034]
As shown in FIG. 6, the microphone R has an inner case 40, and the inner case 40 is accommodated in the outer cover 30 so as to form a void D. The void D is located on the bracket 20 side with respect to the inner case 40. Thereby, even if the vibration from the bracket 20 is transmitted to the outer cover 30, this vibration can be prevented from being transmitted to the inner case 40 by the space D.
[0035]
Here, the inner case 40 is made of a plastic resin such as ABS, and serves as a soundproof member. However, since the inner case 40 is made of a material different from that of the outer cover 30, the inner case 40 and the outer cover 30 have different frequency characteristics of sound to be cut off from each other.
[0036]
The inner case 40 is provided with an opening 41, and the opening 41 faces the exposed plate 12 with the cushion member K interposed therebetween. As a result, the opening 41 penetrates through the sound hole 12 c of the exposed plate 12. Therefore, it is possible to transmit the voice transmitted from the passenger compartment through the opening 41 through the sound hole 12 c and the cushion member K into the inner case 40.
[0037]
The inner case 40 is provided with a partition wall 43, and the partition wall 43 divides the internal space of the inner case 40 into left and right spaces. The microphone element 50 is fitted in the through hole 44 of the partition wall 43 in the inner case 40. Thereby, the microphone element 50 is supported by the inner case 40. Here, the partition wall 43 plays a role of setting the incident direction of the sound wave of the microphone element 50 to a desired direction.
[0038]
As the microphone element 50, a condenser microphone is employed, and the received voice is converted into an electric signal and the electric signal is output through the electric wiring 51. The electrical wiring 51 passes through the through hole 45 of the inner case 40 and also passes through the through hole 31 a of the protrusion 31 of the outer cover 30. Here, the through hole 31 a is configured to tighten the electric wiring 51. Thereby, the vibration transmitted to the electrical wiring 51 can be absorbed by the through hole 31a.
[0039]
Next, a method for assembling the microphone R will be described. First, the outer cover 30, the inner case 40, the microphone element 50, and the cushion member K are separately prepared, and the cushion member K is disposed so as to face the sound hole 12 c of the exposed plate 12. Then, the microphone element 50 is fitted into the through hole 44 of the partition wall 43 of the inner case 40.
[0040]
Next, the outer cover 30 is disposed so as to cover the inner case 40 except for the opening 41 and form a void D. Thereby, the microphone element 50, the inner case 40, and the outer cover 30 are integrated. Further, the opening 41 of the inner case 40 is opposed to the cushion member K.
[0041]
Accordingly, the fitting portions 32a and 32b of the outer cover 30 are fitted to the protrusions 12a and 12b of the exposed plate 12, respectively. Then, the protruding portion 31 of the outer cover 30 is fitted to the fitting portion 21 of the bracket 20. Furthermore, one end of the bracket 20 is fastened to the back surface 11a of the case main body 11 with a screw 500, and the outer cover 30 is pressed toward the exposed plate 12 to be elastically deformed.
[0042]
The features of this embodiment will be described below. In other words, it has a sound hole 12c for passing the transmission voice from the vehicle interior, and is disposed on the outside of the vehicle with respect to the exposed plate 12 that forms the design surface in the vehicle interior, and converts the transmission voice into an electrical signal. The microphone element 50 is disposed on the outer side of the vehicle with respect to the exposed plate 12, is formed of a soundproof member, and is disposed so as to cover the microphone element 50. The microphone element 50 receives the transmitted voice from the sound hole 12c. And an inner case 40 having an opening 41 for transmission.
[0043]
As a result, even if the microphone element 50 is disposed on the vehicle outer side than the exposed plate 12, the inner case 40 is disposed on the vehicle outer side than the exposed plate 12 and is disposed so as to cover the microphone element 50. Therefore, noise can be prevented from being transmitted to the microphone element 50 from other than the opening 41. For this reason, the S / N ratio can be improved without affecting the design of the vehicle.
[0044]
Further, since the outer cover 30 is disposed outside the vehicle from the exposed plate 12 and is disposed so as to cover except the opening 41 of the inner case 40, the microphone is provided from other than the opening 41 of the inner case 40. It is possible to reliably prevent noise from being transmitted to the element 50.
[0045]
Further, when the microphone R is pressed toward the exposed plate 12 by the bracket 20, the outer cover 30 is pressed toward the exposed plate 12 and elastically deformed. Thereby, the clearance gap between the outer side cover 30 and the exposed plate 12 can be eliminated, and the adhesiveness of the outer side cover 30 with respect to the exposed plate 12 can be improved. Therefore, the soundproofing effect of the outer cover 30 can be enhanced.
[0046]
Furthermore, in the above-described embodiment, an example in which the microphone R is mounted on a vehicle has been described.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an automobile equipped with a microphone according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view for explaining the microphone of the embodiment.
FIG. 3 is a perspective view for explaining the microphone according to the embodiment;
FIG. 4 is a perspective view for explaining the microphone according to the embodiment;
FIG. 5 is a top view for explaining the microphone according to the embodiment;
6 is a cross-sectional view taken along line AA in FIG.
FIG. 7 is a view showing a conventional vehicle hands-free device.
[Explanation of symbols]
30 ... Outer cover, 40 ... Inner case, 41 ... Opening, 50 ... Microphone.

Claims (3)

A soundproof structure for a microphone attached to a vehicle,
A design plate (12) having a voice opening (12c) that allows transmission voice from inside the vehicle to pass through, and forming a design surface in the vehicle interior;
A microphone element (50) disposed outside the design board and converting the transmitted voice into an electrical signal;
An opening (disposed on the vehicle outer side than the design plate, formed from a soundproof member, disposed so as to cover the microphone element, and transmitting the transmitted voice from the voice opening to the microphone element ( an inner casing (40) having a 41),
An outer cover (30) formed from a soundproof member and arranged to cover except for the opening of the inner case;
The outer cover is formed of an elastic member,
Furthermore, the soundproof structure of the microphone includes a pressing member (20) that presses the outer cover toward the design plate and elastically deforms the outer cover,
The outer cover is provided with a protrusion (31),
The soundproof structure for a microphone, wherein the pressing member has a fitting portion (21) that fits into the protruding portion . A void (D) is formed between the inner case and the outer cover ,
The soundproof structure for a microphone according to claim 1 , wherein the void is located on the pressing member side. An electrical wiring (51) for outputting an electrical signal converted by the microphone element;
The inner case is provided with a first through hole (45) penetrating the electrical wiring,
Wherein the projecting portion of the outer cover, according to claim 1 or 2, characterized in that the second through-hole penetrating the electrical wires that is penetrating from the first through hole (31a) is provided The soundproof structure of the microphone.

Images