JPH10271592A - Microphone device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To keep the original directivity of a directional microphone even at the time of being housed inside a telephone set case body by providing sound guiding pipes for introducing sound waves on the equivalent positions of the front surface part and back surface part of the directional microphone. SOLUTION: Transmission holes 16 and 17 are provided on the upper part and lower part of the transmitter part of the case body 11 of a portable telephone set, the directional microphone 13 is covered with caps 14 and 15 to be covering bodies and the sound waves are interrupted between the caps 14 and 15. The sound waves made incident on the front surface of the directional microphone 13 through the transmission hole 16 are introduced by the sound guiding pipe 12 and the sound waves made incident on the back surface of the directional microphone 13 through the transmission hole 17 are introduced by the sound guiding pipe 12' similarly. Since both sound guiding pipes are in the same thickness and same length, directional information to the front surface and back surface of the directional microphone is equally guided. Acoustic buffer materials 19 and 19' suppress the acoustic resonance of the sound guiding pipes. Since the transmission holes 16 and 17 are turned to the direction of the mouth for uttering communication voice, clear communication is performed even in high noise.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microphone device used for a portable telephone used in a place with large ambient noise such as a portable telephone and a PHS.

[0002]

2. Description of the Related Art FIG. 4 is a side view and a partially enlarged sectional view showing the structure of a portable telephone including a conventional microphone device. FIG. 4 (a) shows the appearance of the portable telephone, and FIG. 3 shows a part of the microphone device. A conventional microphone device such as a mobile phone has a structure in which the front surface of the directional microphone 1 is housed inside the sound hole portion 3 of the phone housing 2 as described above. 4 is a supporting device for the directional microphone 1 and 5 is a directional microphone 1
Lead wire.

[0003]

However, in such a conventional configuration, sound waves entering through the sound hole 3 of the telephone casing 2 interfere with the inside of the sound hole 3 because the sound hole 3 has a small volume. Phase information of sound waves between two points on the front and back of the directional microphone 1 for obtaining directional characteristics is lost, making it difficult to obtain practical directional characteristics. As described above, the phase of the incident sound wave in the small volume portion is completely disturbed, as described above, as the information on the direction of arrival of the sound wave given to the front and back of the directional microphone, so that directivity cannot be obtained. Was. Therefore, in a telephone having a built-in directional microphone, there is a problem that it is extremely difficult to select and transmit a target transmission voice with respect to ambient noise.

The present invention solves the above-mentioned conventional problems. Even if the directional microphone is housed inside the telephone case, the directional microphone can maintain its original directional characteristics, and the directional microphone can be protected against ambient noise. It is an object of the present invention to provide a microphone device having extremely good selectivity of transmitted voice.

[0005]

A microphone device according to the present invention comprises a directional microphone and a cover for covering the directional microphone, and a sound is provided at positions corresponding to the front and rear portions of the directional microphone of the cover. It has an introduction hole for introducing sound waves through a conduit.

According to the present invention, even when the directional microphone is housed inside the telephone case, the directional characteristics inherent in the directional microphone can be maintained, and the selectivity of the transmitted voice with respect to the ambient noise is extremely good. Microphone device can be obtained.

[0007]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a cross-sectional view showing a configuration of a microphone device according to Embodiment 1 of the present invention. FIG. 1 (a) shows an entire main part thereof, and FIG. Only the microphone part is shown in an enlarged manner. In FIG. 1 (a), transmission holes 16 and 17 are provided in the upper and lower portions of a transmitter section of a housing 11 of a mobile phone, and a close-talking type microphone or a directional microphone using an electret is provided.
A sound input terminal 13 above and below is covered with a cap 14 and a cap 15 serving as a cover, and the peripheral portions of both caps are hermetically closed, and a sound wave is generated between the cap 14 and the cap 15. Is completely shut off. FIG. 1B shows an enlarged view of the directional microphone 13 and the caps 14 and 15.

The cap 14 and the cap 15 are provided with an introduction hole 14 'and an introduction hole 15' for introducing a sound wave, respectively.
Are connected to two sound conduits 12 and 12 'having the same thickness and the same length. Acoustic damping members 19, 19 'are inserted into the sound conduits 12, 12', respectively, and an output signal lead 18 of an electric signal from the directional microphone 13 is connected between the cap 15 and the directional microphone 13. It is drawn out through the gap.

Next, the operation will be described. Transmission hole 16
The sound wave incident on the front surface of the directional microphone 13 through is transmitted by the sound conduit 12, and the sound wave incident on the rear surface of the directional microphone 13 is introduced by the sound conduit 12 ′. In this way, the front and back of the directional microphone 13 can receive the directional characteristic information obtained by placing the directional microphone 13 in the free sound field space through the sound conduit 12 and the sound conduit 12 ′, and in particular, Since the two sound conduits have the same thickness and the same length, the directivity information to the front and back of the directional microphone is equally guided. In addition,
Of course, since the directional characteristics of the directional microphone are directed toward the mouth that emits the call voice, clear calls can be made even in high noise.

[0011] Even if a directional microphone is simply installed in a transmitter space provided inside a mobile phone housing as in the conventional concept, such directional information is disturbed and the direction of arrival of sound waves. Could not be detected, and the separation of the external noise and the call voice could not be performed at all.However, if the directional microphone 13 is incorporated in the mobile phone housing 11 by the above-described means, the directional microphone 13 The sound field around the transmitter can be directly introduced into the sound field through the transmission holes 16 and 17 and the sound conduits 12 and 12 ', so that the sound field information applied to the front and back of the directional microphone 13 is transmitted as it is, The function can be exhibited without impairing the directional characteristics and close-talk characteristics of the microphone 13.

As described above, according to the present embodiment, the sound field around the transmitter can be directly applied to the front and back of the directional microphone through the transmission hole and the sound conduit.
The function of the directional microphone can be sufficiently exhibited without impairing the directional characteristics and the close-talking characteristics. If a rubber tube or a similar flexible tube is used for the sound conduit, the vibration of the housing to the directional microphone can be prevented, and the flexibility of the tube allows the directional microphone to be installed in a place where the directional microphone is installed. Some flexibility is obtained, and it is less susceptible to structural constraints. In addition, the acoustic damping material inserted in the sound conduit not only sufficiently suppresses the acoustic resonance characteristics caused by the sound conduit, but also allows the external sound field characteristic to be transmitted to the directional microphone as it is, It is possible to suppress the generation of blowing noise due to the breath generated at the time of transmission, and secure a clear call.

(Embodiment 2) FIG. 2 shows a configuration of a main part of a microphone device according to Embodiment 2 of the present invention.
(a) is a sectional view thereof, and FIG. 2 (b) is a front view thereof. In addition,
The same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted. This embodiment is a modification of the first embodiment in which the shapes of the caps 14 and 15 are changed, and is characterized by the position of the sound wave introduction hole. FIG.
As shown in (a), the front and back portions of the directional microphone 13 are covered with caps 20 and 21 serving as covering bodies, and introduction holes 20 'and 21' for connecting a sound conduit are provided in the directional microphone 13 respectively. It is configured to face the diametrical direction of the peripheral portion. The lead wire 18 of the directional microphone is drawn out from the gap between the cap 20 and the directional microphone 13. Two sound pipes of the same thickness and the same length, one end of which is connected to the transmission hole of the mobile phone as described in the first embodiment, are connected to the sound wave introduction holes 20 'and 21'. External sound waves are introduced through the sound conduit.

As described above, according to the present embodiment, since the introduction holes for connecting the sound conduits are oriented in the diametrical direction of the peripheral portion of the directional microphone, the connected sound conduits are drawn in the same direction. Therefore, there is an advantage that a degree of freedom can be obtained in a place where the directional microphone is installed inside the mobile phone, and the directional microphone can be easily accommodated in a small space.
In particular, the thickness of the directional microphone portion can be suppressed to a small thickness in a mobile phone that is made thinner, which facilitates storage. The other effects of preventing vibration of the directional microphone are exactly the same as those in the first embodiment.

(Embodiment 3) FIG. 3 shows a configuration of a main part of a microphone device according to Embodiment 3 of the present invention.
(a) is a sectional view thereof, and FIG. 3 (b) is a front view thereof. In addition,
The same parts as those in the first and second embodiments are denoted by the same reference numerals, and detailed description thereof will be omitted. This embodiment uses a cover housing different from the structure of the cap in each of the above embodiments, and is characterized by its configuration. That is, as shown in FIG.
And a cover housing 22 that completely separates the front and rear surfaces of the device and completely covers the entire body with the directional microphone 13 interposed therebetween, which is mounted on a mobile phone. FIG. 3 shows the front appearance structure of the covered casing 22.
(b). A sound conduit for introducing sound waves to the front and back of the directional microphone 13
23, 23 'are connected to each other to form an integrated structure.
Further, the covering casing 22 can be opened to both the left and right with the vertex portion 24 of the casing as a fulcrum, and the intermediate point 25 between the sound conduits 23 and 23 '.
Is open. As a material for forming the covering casing 22, a rubber-based material such as silicon rubber, a plastic-based material such as ABS, or the like is used. The lead 18 from the directional microphone is connected to the sound conduit 2 as shown in FIG.
It is drawn out from the gap between the intermediate points 25 of 3, 23 '.

Next, the operation will be described. Fig. 3 (a)
As shown in (b) and (b), the sheath housing 22 has its vertex 24
Since the main body of the directional microphone 13 is completely sandwiched with the fulcrum as a fulcrum, the peripheral portion of the directional microphone 13 is hermetically sealed, so that sound wave leakage from the front and back of the directional microphone 13 is blocked, and Each sound wave introduced through sound conduits 23, 23 'having one end connected to the speech hole is introduced into the directional microphone 13 symmetrically on both the front and the back, and no other sound waves are introduced, and The directional characteristics can be made the best.

As described above, according to the present embodiment, leakage of sound waves from the front and back of the directional microphone is blocked by the covering housing, and each sound wave introduced through the sound conduit is symmetrical on both the front and back. Since the sound wave is introduced into the directional microphone and no other sound waves are introduced, the directional characteristics of the directional microphone can be made the best. In addition, since the covering housing is integrally formed, it is easy to manufacture with a mold, and it is easy to store the directional microphone and the workability is good. In addition, when the covering housing is molded using, for example, a rubber-based material and the directional microphone is stored, the covering housing itself has an anti-vibration structure, so that vibration is not transmitted to the directional microphone. Vibration noise due to vibration from the telephone housing can be prevented.

[0018]

As described above, according to the present invention, the sound field around the transmitter can be directly applied to the front and back surfaces of the directional microphone through the transmission hole and the sound conduit, so that a small housing like a portable telephone can be obtained. Even with a close-talking microphone and a directional microphone stored in the body, the advantageous effect that the performance inherent to the directional microphone can be maximized without deteriorating the close-talking characteristics and the directional characteristics at all is obtained. Can be

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration of a microphone device according to a first embodiment of the present invention.

FIGS. 2A and 2B are a sectional view and a front view showing a configuration of a main part of a microphone device according to a second embodiment of the present invention.

FIGS. 3A and 3B are a cross-sectional view and a front view illustrating a configuration of a main part of a microphone device according to a third embodiment of the present invention.

FIG. 4 is a side view and a cross-sectional view illustrating an example of a configuration of a conventional microphone device.

[Explanation of symbols]

11 ... mobile phone case, 12, 12 ', 23, 23' ... sound conduit,
13 ... directional microphone, 14, 15 ... front and back caps, 16, 17 ... communication hole, 18 ... directional microphone lead wire, 19, 19 '... acoustic damping material, 20, 21 ...
Cap, 22 ... Coated housing.

Claims (2)

[Claims] 1. A directional microphone and a cover covering the directional microphone, and an introduction hole for introducing sound waves by a sound conduit is provided at a position corresponding to the front and back of the directional microphone of the cover. A microphone device, which is provided. 2. A directional microphone, and a cover for covering the directional microphone, wherein the cover has a shape surrounding the directional microphone, and corresponds to a position corresponding to a front part and a rear part of the directional microphone. The microphone device is characterized in that a sound conduit for introducing a sound wave is formed integrally therewith.