JP2987490B2 - Bidirectional microphone and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bidirectional microphone in which a bidirectional microphone is housed in the center of a cylindrical pipe, and a method of manufacturing the microphone.

[0002]

2. Description of the Related Art Japanese Patent Application Laid-Open No. Hei 6-189388 filed by the present applicant discloses a bidirectional microphone in which a bidirectional microphone is accommodated in a cylindrical pipe. In this application, the bidirectional microphone according to the present invention is one in which an earphone and a microphone are integrated. The configuration and operation of the bidirectional microphone are as follows.

[0003] A bidirectional microphone is accommodated in the center of the center of a cylindrical pipe, and Japanese paper,
It is filled with a fibrous sound absorbing material such as cotton. The effect is that the sound is collected by directing one of the pipes in the direction of the mouth of the talker, so that the sound level is different from the sound level collected from the other direction of the pipe. A sound output can be obtained.

On the other hand, ambient noise often reaches from a horizontal surface for practical use, and the speech is generally at least ten times as long as the distance from the mouth. Are at the same level, they are canceled and canceled each other, so that only the voice of the talker is output without being affected by external noise, for example, as a handset of a mobile phone or a desk-top type This is very effective as a hands-free handset in a telephone.

[0005]

By the way, in order to manufacture such a bidirectional microphone, it is necessary to realize the following various characteristics. That is, the entrance of sound to pipes attached before and after the microphone is limited to only the openings of the two pipes. That is, no sound leaks from the peripheral surface of the microphone or the lead wire outlet. The surface structure of the microphone must have a sufficiently large mechanical strength to withstand practical use.

Further, the assembling work is simple in mass production. Ability to measure electrical performance before completion. It is possible to cope with various external designs and to have a sufficiently large electric withstand voltage.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to eliminate the necessity of increasing the accuracy of a pipe into which a microphone is inserted, so that the accuracy of a mold is not required. Accordingly, it is an object of the present invention to provide a bidirectional microphone and a method for manufacturing the same, which can reduce the cost and increase the degree of freedom in design.

[0008]

SUMMARY OF THE INVENTION A bidirectional microphone according to the present invention achieves the above-mentioned object, and comprises a tubular pipe, a pipe fixed to the center of the pipe, and a lead portion connected to the pipe. A bidirectional microphone that is derived from a notch formed in the pipe and is closed so that the notch does not leak, a sound-absorbing material filled on the sound-collecting side of the microphone in the pipe, And a shell having both ends opened for receiving mechanical vibration from being transmitted to the pipe.

The method of manufacturing a bidirectional microphone includes the steps of press-fitting both ends of the bidirectional microphone in the axial direction into two cylindrical pipes and leading out leads from the microphone, And a step of housing the pipe in a two-part shell so that mechanical vibration is not transmitted to the pipe.

[0010] Further, another method of manufacturing a bidirectional microphone is to mount a bidirectional microphone in the center of a pipe body formed in a semi-cylindrical shape and to match the end face of the pipe body with a cylindrical pipe. A step of leading a lead from the microphone through a notch of the pipe body to close the notch, a step of filling both ends of the pipe with a sound absorbing material, and that mechanical vibration is not transmitted to the pipe. In a shell divided into two parts as described above.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the structure of a bidirectional microphone according to the present invention will be described below with reference to FIGS. Reference numeral 1 denotes a relatively soft synthetic resin pipe divided into two in the vertical or horizontal direction as in a manufacturing method described later, and a bidirectional microphone 2 is housed in the center of the interior in a tightly contacted state. Reference numeral 3 denotes a flexible substrate 3 having a lead portion connected to an electrode (not shown) of the microphone 2 by soldering, and is led out of the cutout portion of the pipe 1 in a sealed state. The details of the manufacturing process of this portion will be described later.

Reference numeral 4 denotes a fibrous sound-absorbing material such as Japanese paper or cotton inserted at both ends of the microphone 2 in the pipe 1. Reference numeral 5 denotes a pipe for closing the sound-absorbing material 4 so that the sound absorbing material 4 does not jump out. Caps made of a metal net or synthetic resin covered on both ends, 6 is an elastic member such as a sponge for covering the outer periphery of the pipe 1, and 7 is a vertical member for accommodating the pipe 1 in a state where the elastic member 6 is wound. Openings 7a for voice introduction are formed at the upper and lower ends of the divided shell made of hard synthetic resin.

A guide 7c having a groove 7b into which the support plate 8a of the wire connector 8 is inserted is integrally formed on a side surface of the opening of the shell 7 into which the pipe 1 is inserted. Then, the lead wire 8b from the wire connector 8
Is connected to the other end of the lead portion of the flexible substrate 3 by soldering.

To explain the assembling process of the bidirectional microphone of the present invention thus constructed, after connecting the lead wire b of the wire connector 8 to the flexible board 3 led out of the pipe 1, the outer periphery of the pipe 1 will be described. Elastic member 6
And the pipe 1 is fitted into one of the shells 7 in this state.

Next, with the support plate 8a of the wire connector 8 inserted into the guide 7c of the shell 7, the other shell 7 is fitted from the other end of the pipe 1. At this time, the supporting plate 8a is inserted into the guide 7c of the other shell 7. And it can be integrated by bonding a pair of joining parts with an adhesive.

In the bidirectional microphone having such a structure, since the microphone 2 is sealed in the case 1 made of a relatively soft material except at both ends, sound leakage may occur in the case 1. Therefore, highly accurate bidirectionality can be realized.

Further, even though the case 1 is made of a relatively soft material, the shell 7 is made of a hard material, so that the product has high strength and excellent durability. Is accommodated via the elastic member 6, so that touch noise applied to the shell 7 can be reduced.

Next, an embodiment of a method of manufacturing the microphone 2 in the case 1 will be described with reference to FIGS. First, the structure of the microphone 2 will be described with reference to FIG. The diaphragm is housed in an aluminum case 2a,
A sound opening 2b is opened on both lid surfaces, and an electrode 2c is formed on one lid surface. The lead 3a of the flexible substrate 3 is soldered to the electrode 2c.

A method of manufacturing the microphone 2 to which the flexible board 3 is connected in the case 1 will be described. First, a pair of relatively soft synthetic resin pipes 1 having an inner diameter slightly smaller than the outer shape of the microphone 2 is prepared. In addition, one pipe 1 has an opening 1a for leading out the flexible substrate 3 to the outside.
Are formed (see FIG. 5).

Then, approximately half of the microphone 2 in the longitudinal direction is press-fitted into the pipe 1 on which the opening 1a is not formed (see FIG. 6). Next, with the flexible substrate 3 inserted from the inside into the opening 1a of the other pipe 1, a half part of the microphone 2 is press-fitted into the pipe 1 (see FIG. 7).

Next, the gap between the openings 1a of the pipe 1 from which the flexible board 3 is led out is closed by an adhesive 1b so that sound leakage does not occur. Next, a fibrous sound absorbing material 4 such as Japanese paper, cotton, or the like is inserted into the empty room from the opening side of the pipe 1 (see FIG. 8). Finally, the opening into which the sound absorbing material 4 is inserted is closed by a metal net or a synthetic resin net 5 to prevent the sound absorbing material 4 from coming off (FIG. 9).
reference).

In the above-described embodiment, the manufacturing method of press-fitting the microphone 2 into the two pipes 1 has been described, but another manufacturing method will be described with reference to FIGS.
In the present embodiment, two flanged semi-cylindrical pipe members 1 made of relatively soft synthetic resin are prepared. An opening 1a for inserting the flexible substrate 3 is formed in one pipe member 1 (see FIG. 10).

Then, a microphone 2 having an elastic band wound around its outer peripheral surface is placed on the central portion of the pipe member 1 on which the opening 1a is not formed (FIG. 11).
reference). Then, the two pipe members 1 are overlapped with the flexible substrate 3 inserted into the opening 1a of another pipe member 1. At this time, an adhesive is applied to the joining surfaces to be integrated (FIG. 12), and the flange portion is cut, so that the pipe material 1 becomes a pipe shape (see FIG. 13).
Note that the microphone 2 is made of a pipe material 1 by an elastic band.
Is fixed without backlash.

Next, the gap of the opening 1a of the pipe 1 from which the flexible board 3 is led out is closed by an adhesive 1b so that sound leakage does not occur. Next, a fibrous sound absorbing material 4 such as Japanese paper, cotton, or the like is inserted into the empty room from the opening side of the pipe 1 (see FIG. 14). Finally, the opening into which the sound absorbing material 4 is inserted is closed by a metal net or a synthetic resin net 5 to prevent the sound absorbing material 4 from coming off (see FIG. 15).

The microphone unit manufactured by the above-described manufacturing method is housed in the shell 7 as described with reference to FIGS. 1 to 3 to complete the bidirectional microphone.

In the bidirectional microphone manufactured by the above-described manufacturing method, since the pipe that houses the microphone is made of a relatively soft material,
The microphone can be pressed into the pipe without air leakage,
Therefore, attenuation of sound waves due to sound leakage is eliminated. Further, since the microphone unit is housed in a shell made of a hard material, the microphone unit is not damaged.

In the above-described embodiment, when the pipe 1 is accommodated in the shell 7, the elastic member 6
Is wound around the outer peripheral surface of the pipe 1, and as a means for eliminating the play between the pipe 1 and the shell 7, a material having elasticity is used for the cap 5. It is also conceivable to eliminate backlash between the shell 7 and prevent the touch noise from being transmitted to the microphone 2.

[0028]

As described above, according to the present invention, the attenuation of sound waves due to sound leakage in the pipe can be eliminated, the microphone unit can be protected, and an elastic material is interposed between the shell and the pipe. Accordingly, generation of noise due to external vibration can be prevented.

The microphone is mounted on the pipe by press-fitting it into two pipes made of a relatively soft material or by wrapping the microphone in a pipe divided in the longitudinal direction, so that a mold for manufacturing the pipe is used. This does not require precision, the production cost can be reduced, and the electrical performance does not change even if the shape of the shell is changed a lot, so that there is an effect that the degree of freedom in design can be obtained.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a bidirectional microphone according to the present invention.

FIG. 2 is a perspective view showing an assembled state of the same.

FIG. 3 is a longitudinal sectional view of the same.

FIG. 4 shows a bidirectional microphone, (a) is a bottom view,
(b) is a side view, and (c) is a plan view.

FIG. 5 is a perspective view of a first step showing a first manufacturing method.

FIG. 6 is a perspective view showing a second step of the above.

FIG. 7 is a perspective view showing a third step.

FIG. 8 is a perspective view showing a fourth step.

FIG. 9 is a perspective view of a completed state of the microphone unit.

FIG. 10 is a perspective view of a pipe used in a second manufacturing method.

FIG. 11 is a perspective view showing a first step of the above.

FIG. 12 is a perspective view illustrating a second step.

FIG. 13 is a perspective view showing a third step.

FIG. 14 is a perspective view illustrating a fourth step.

FIG. 15 is a perspective view of a completed state of the microphone unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pipe 2 Microphone 3 Flexible board 4 Sound absorbing material 6 Elastic member 7 Shell

Claims (3)

(57) [Claims] 1. A bi-directional pipe having a tubular pipe and a lead fixed to a center of the pipe, a lead part being led out of a notch formed in the pipe, and the notch being closed to prevent sound leakage. A bidirectional microphone comprising: a microphone, a sound-absorbing material filled on the sound collecting side of the microphone in the pipe, and a shell having both ends opened so that mechanical vibration is not transmitted to the pipe. 2. A step of press-fitting both ends in the axial direction of a bidirectional microphone into two tubular pipes and leading a lead portion from the microphone, and filling both ends of the pipe with a sound absorbing material. Accommodating the pipe in a shell divided into two parts so that mechanical vibration is not transmitted to the pipe. 3. A bidirectional microphone is placed at the center of a pipe member formed in a semi-cylindrical shape, and the end faces of the pipe member are aligned to form a cylindrical pipe, and a lead portion from the microphone is provided. A step of closing the notch by drawing out from a notch of the pipe body; a step of filling both ends of the pipe with a sound absorbing material; and a shell divided into two so that mechanical vibration is not transmitted to the pipe. A method of manufacturing a bidirectional microphone comprising the steps of accommodating.