JPH08102778A - Transmitter - Google Patents

Abstract

PURPOSE: To make surrounding noise small and to make the voice of a transmitting person easily listenable even when the surrounding noise is large. CONSTITUTION: This transmitter is provided with a grasping part main body 100 and a bidirectional microphone housed in the grasping part main body 100 and the bidiretional microphone is provided with front surface sound holes 141 leading to the front surface side of a diaphragm and back surface sound holes leading to the back surface side of the diaphragm. Then, the bidirectional microphone is attached projectably from the grasping part main body 100, the back surface sound holes are opened in a projecting state and the back surface sound holes are closed in a housed state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmitter used for telephones, portable radios and the like.

[0002]

2. Description of the Related Art A mobile phone will be described below as an example. The mobile phone is composed of a grip portion main body which is gripped by a user with a hand, and a microphone and a receiver which are stored in the grip portion main body. An omnidirectional microphone is usually used as the microphone.

[0003]

Since sound pressure is applied to the diaphragm of the omnidirectional microphone from only one direction, the voice of the talker and ambient noise are similarly applied to the diaphragm.
Therefore, a signal containing the voice of the sender and ambient noise is output to the receiver side. Therefore, if the ambient noise is large, it becomes difficult to hear the voice of the sender.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a transmitter in which the ambient noise is reduced even when the ambient noise is large and the voice of the speaker is easily heard. There is.

[0005]

A transmitter according to the present invention comprises:
A transmitter having a grip body and a bidirectional microphone housed in the grip body, wherein a front sound hole communicating with a front side of a diaphragm of the bidirectional microphone and a rear side of the diaphragm. And a rear surface sound hole, which is openable and closable.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic plan view of a portable telephone to which a transmitter according to a first embodiment of the present invention is applied in a place where there is no noise around, and FIG. 2 is a schematic plan view of the first embodiment of the present invention. FIG. 3 is a schematic plan view of a mobile phone to which the transmitter according to the embodiment is applied in a place where there is noise around the surroundings. FIG. 3 is a frame of the mobile phone to which the transmitter according to the first embodiment of the present invention is applied. FIG. 4 is a schematic rear view of a mobile phone to which the transmitter according to the second embodiment of the present invention is applied.

A mobile phone to which the transmitter according to the present embodiment is applied has a two-folded grip body 100 and a bidirectional microphone 200 housed in the grip body 100.
And a receiver (not shown).

The grip portion main body 100 has a lower main body portion 110 provided with a plurality of push switches 111 and an upper main body portion 120 openably and closably connected to the lower main body portion 110 via a hinge portion 130. are doing.

A substantially fan-shaped frame 140 is rotatably attached to a lower end corner of the lower body 110 by a pin 150. A recess 112 corresponding to the shape of the frame 140 is formed at the lower end corner of the lower main body 110 to which the frame 140 is attached so that the frame 140 is flush when stored.

The frame 140 houses the bidirectional microphone 200. A front sound hole 141 is formed on the front surface of the frame 140, that is, on the mouth side of the speaker, and a rear sound hole 142 is formed on the rear surface side.

A through hole 143 for the pin 150 is formed in the frame 140. In addition, 1 in FIG.
Reference numeral 44 is a vibration-proof material for holding the bidirectional microphone 200.

The front sound hole 141 is on the front side of the diaphragm 210 of the bidirectional microphone 200 housed in the frame 140, and the rear sound hole 142 is the rear surface of the diaphragm 210 of the bidirectional microphone 200 housed in the frame 140. They are facing each other.

As shown in FIG. 3, the front sound hole 141 and the rear sound hole 142 have the same condition, that is, the same size, position, and number, and from the diaphragm 210 of the bidirectional microphone 200 to the front sound hole 141. Distance and the rear sound hole 14
The distance to 2 is set to be equal.

As shown in FIG. 1, by rotating the frame 140 around the pin 150 so that the bidirectional microphone 200 is projected from the lower main body 110, the rear surface sound hole 1 is formed.
42 is opened. Further, when the frame 140 is housed in the recess 112 as shown in FIG.
Is closed by the lower body 110.

On the other hand, the upper main body portion 120 of the grip portion main body 100.
Has a receiver stored at the upper end. In the drawing, 121 is a slit through which sound from the receiver passes,
A display panel 122 displays a telephone number, a usage method, and the like.

The mobile phone thus constructed is sized so that the frame 140 is positioned in the mouth when the receiver is placed near the ear.

Next, the operation of the transmitter thus constructed will be described. First, the case of using in a quiet place where there is no noise around will be described. In this case, the frame 140 is used while being housed in the recess 112 of the lower body 110. Then, the voice of the user is guided to the front surface of the diaphragm 210 of the bidirectional microphone 200 via the front sound hole 141 of the mouth, and a signal corresponding to the voice is output from the bidirectional microphone 200. Here, the rear surface sound hole 1
Since 42 is in a closed state, voice is not guided to the diaphragm 210 via the rear sound hole 142.

When used in a place where there is noise in the surroundings in this state, the surrounding noise is guided to the diaphragm 210 through the front sound hole 141. In this case, noise makes it difficult to hear the voice.

If the frame 140 is rotated to project the bidirectional microphone 200, the voice can be heard easily. This is because the bidirectional microphone 200 is projected so that the rear surface sound hole 14 of the frame 140 is
2 is open.

That is, since the noise source can be considered to be far away, the distance from the noise source to the front surface of the diaphragm 210 can be considered to be equal to the distance to the rear surface of the diaphragm 210. Noise introduced to the front surface of the diaphragm 210 through the front sound hole 141 and the rear sound hole 14
The noise is equal to the noise guided to the rear surface of the diaphragm 210 via 2, and the vibration of the diaphragm 210 due to the noise is canceled, so that the signal based on the noise is not output from the bidirectional microphone 200.

On the other hand, since the mouth, which is the sound source of the user's voice, is close to the bidirectional microphone 200, the distance from the mouth to the front surface of the diaphragm 210 and the mouth to the diaphragm 2 are large.
With the distance to the rear surface of 10, the former is much shorter. Therefore, the voice guided to the front surface of the diaphragm 210 via the front sound hole 141 and the voice guided to the rear surface of the diaphragm 210 via the rear sound hole 142 are louder in the former direction and are bidirectional. This is because voice is output from the microphone 200. This makes it easier to hear the voice even if there is noise in the surroundings.

Next, a mobile phone to which the transmitter according to the second embodiment is applied will be described with reference to FIG. In the mobile phone to which the transmitter according to the second embodiment is applied, the bidirectional microphone 200 (not shown in FIG. 4) is housed inside the lower main body 110 of the grip main body 100. The rear surface sound hole 113 formed on the rear surface side of the lower main body 110 has a shutter-like opening / closing mechanism 150.
It can be opened and closed by.

The opening / closing mechanism 150 is provided on the back side of the lower body 110, and has a lid 151 capable of closing all the rear surface sound holes 113, and a knob 152 protruding from the lid 151. are doing.

Inside the back surface of the lower body 110, the lid 15
A supporting portion (not shown) that slidably supports 1 is provided. In addition, a slit 114 is formed on the back surface side of the lower main body 110 to guide the knob portion to the outside.

That is, the rear surface sound hole 113 is opened and closed by sliding the lid portion 151 with the knob portion 152 led out from the slit 114. As shown in FIG. 4B, when the rear surface sound hole 113 is opened, the voice of the speaker becomes clear and easy to hear even in a place where there is noise in the surroundings, as described above.

In this case, the sound is transmitted through the slit 114 to the diaphragm 210 of the bidirectional microphone 200.
It is necessary to provide a sound insulation wall (not shown) between the slit 114 and the bidirectional microphone 200 so that the sound insulation wall is not guided to.

In the above-mentioned embodiment, the two-fold type portable telephone is taken as an example, but the present invention is not limited to this, and it can be applied to a handset or the like of an ordinary telephone. Is.

[0028]

The transmitter according to the present invention includes a grip body and
A transmitter having a bidirectional microphone housed in the grip body, the front sound hole communicating with the front side of the diaphragm of the bidirectional microphone, and the rear sound hole communicating with the rear surface of the diaphragm. And the rear side sound hole can be opened and closed. Therefore, when using it in a place with noise around it, if you open the rear sound hole, the noise will be transmitted to both the front and back sides of the diaphragm at the same level, so it will be canceled out and the voice of the user will be relatively clear and easy to hear. Of.

If the bidirectional microphone is attached to the body of the grip portion so that it can project, the rear sound hole is opened in the projecting state, and the rear sound hole is closed in the stored state. Just by protruding the microphone,
Since the rear surface sound hole is opened, the same effect as described above can be obtained.

Further, if the bidirectional microphone is housed inside the grip body and the rear sound hole can be opened / closed by an opening / closing mechanism, the bidirectional microphone can be opened without protruding from the grip body. The same effect as can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic plan view when a mobile phone to which a transmitter according to a first embodiment of the present invention is applied is used in a place where there is no noise around.

FIG. 2 is a schematic plan view of a mobile phone to which the transmitter according to the first embodiment of the present invention is applied when it is used in a place where there is noise around it.

FIG. 3 is a schematic cross-sectional view of a frame of a mobile phone to which the transmitter according to the first embodiment of the present invention is applied.

FIG. 4 is a schematic rear view of a mobile phone to which a transmitter according to a second embodiment of the present invention is applied.

[Explanation of symbols]

 100 grip body 200 bidirectional microphone 210 diaphragm

Claims (3)

[Claims] 1. A transmitter having a grip portion main body and a bidirectional microphone housed in the grip portion main body,
It has a front sound hole communicating with the front side of the diaphragm of the bidirectional microphone and a rear sound hole communicating with the rear side of the diaphragm, and the rear sound hole is openable and closable. Characteristic transmitter 2. The bidirectional microphone is mounted so as to be capable of projecting from the grip body, and the rear sound hole is opened in the projecting state, and the rear sound hole is closed in the housed state. The transmitter according to item 1. 3. The transmitter according to claim 1, wherein the bidirectional microphone is housed inside a grip body, and the rear sound hole can be opened and closed by an opening / closing mechanism.