JPS6328560B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention electrically converts bone conduction audio signals from the ear canal wall and transmits them to the outside via a transmitter as electrical signals, and also converts audio signals from a speaker that converts the electrical signals from a receiver. This invention relates to a two-way communication device in the ear canal that leads to the ear canal.

Conventionally, there have been two types of two-way communication devices that combine an ear canal microphone and a speaker: one in which the speaker is housed in the same case as the microphone, and one in which the speaker is provided outside and guided into the case by a sound conduit.

By the way, in the case of the former mentioned above, the speaker is installed behind the vibroelectric transducer such as a piezoelectric element, which is the audio pickup, and the sound from the speaker is transmitted into the ear canal through the sound conductor formed in the case. A sound is emitted. However, in this type of device, as the sound level passing through the sound guide increases, through the mechanical coupling between the speaker and the case, especially the vibration of the speaker itself leaks to the conversion element side and approaches the user's sound level. Sometimes. As a result, in two-way calls that use a single carrier frequency with a voice-based automatic transmission/reception switching device (VOX circuit), a malfunction occurs in which the receiving side switches to the transmitting side based on the audio signal, which makes manual switching impossible. At least one hand had to be used when communicating. As a result, there was a problem in that the work was temporarily interrupted, or even if the work was not interrupted, the focus was on communication, resulting in a lack of safety.

Furthermore, in wired two-way communication or wireless two-way communication using two carrier frequencies, howling occurs as the level of the received audio signal increases, making communication virtually impossible. Therefore, to date, this type of device has not been manufactured.

Therefore, the latter method is used, in which a speaker is provided externally and sound is guided into the ear canal through a sound conduit. According to this method, the vibration of the speaker itself is not transmitted to the conversion element, and two-way communication becomes possible.
However, when trying to make a two-way call in a high-noise environment with 100 horns or more, the audio output of the speaker must be increased in proportion to the surrounding noise, but at this time the following inconvenience occurs, making it impossible to make a two-way call. becomes.

That is, when the audio output from the speaker is increased, the audio energy passing through the sound pipe increases, and the vibration energy leaking from the sound pipe is transmitted to the conversion element. And since the sound pipe is a mechanical connection between the speaker and the case,
It must have a certain degree of strength, and it is difficult to connect the sound pipe and case only with a material with a large elastic modulus and separate the vibration system. Therefore, even with this method, the same drawbacks as in the former case occur when the output of the speaker is increased.

The present invention has been made to correct the above-mentioned drawbacks, and its purpose is to enable two-way communication with high clarity without using both hands even under high noise conditions, and to prevent the occurrence of malfunctions. An object of the present invention is to provide a two-way communication device within an ear canal that can prevent the occurrence of howling.

Next, one embodiment of the present invention will be described with reference to the drawings.

Reference numeral 1 denotes an insert body made of a material having a large mass such as zinc die casting, which is inserted into the external auditory canal, and has a through hole 1a and an insertion hole 1b formed therein. Reference numeral 2 denotes a vibroelectric conversion element such as a piezoelectric element or an electret that is inserted and fixed into the insertion hole 1b, and converts the bone conduction sound vibration in the external auditory canal transmitted to the insert 1 into an electric signal. Reference numeral 3 designates an external damper that is adhesively fixed to the back surface of the insert 1 and is made of molded silicone rubber or urethane rubber with a hardness of 30° or more. Reference numeral 4 denotes an outer body fixed to the insert 1 via an external damper 3, and like the insert 1, it is made of a large material. And this outer body 4
A speaker accommodating portion 4a is formed therein. Reference numeral 5 denotes a speaker, which is housed in the speaker housing 4a in a suspended state by a speaker damper 6 made of a material with a high elastic modulus (for example, a molded silicone gel that can maintain a certain shape). . Reference numeral 7 designates a sound conduit made of a thin silicone tube with a large elastic modulus, one end of which is connected to the sound emitting part 5a of the speaker 5, and the insert body 1 is passed through the space of the external damper 3.
is inserted into the through hole 1a of. Reference numeral 8 denotes a metal pipe to which the other end of the sound guide tube 7 is connected, and its tip is opened at the tip of the insert body 1. Reference numeral 9 designates a sound guide damper that elastically supports the metal pipe 8 on the insert 1, and is made of a material with a large elastic modulus. That is, the same material as the damper 6 of the speaker 5 is used. Reference numeral 10 denotes a relay board fixed to the surface of the outer body 4, to which lead wires 2a and 5b from the conversion element 2 and the speaker 5 are connected. Since the lead wires 2a and 5b require a high elastic modulus, extremely thin stranded wires are used.
11 is the lead wire 2a and 5b via the relay board 10.
An external lead wire 12 connected to the outer body 4 is an outer sheath that covers the surface of the outer body 4 and even the outer lead wire 11 is molded. The lead wire 2a is the external lead wire 1.
1 to the transmitter, and the lead 5b is likewise connected to the receiver via an external lead 11.

Next, to explain the operation, the sound generated by the user is transmitted to the insert body 1 as bone conduction vibration, and the vibration is converted into an electric signal by the conversion element 2. This electric signal is impedance-converted by an impedance conversion circuit (not shown) provided on the back of the conversion element 2, and is sent to an external lead wire 11 via the lead wire 2a and the relay board 10, and from the external lead wire 11 to the transmitter. is sent to the other party, radiated as radio waves (or via wire), and transmitted to the other party.

On the other hand, the audio signal from the other party is received by the receiver as a wireless or wired signal, and the external lead wire 1
1. The signal is transmitted to the speaker 5 via the lead wire 5b. Therefore, the speaker 5 is driven and the sound is emitted into the ear canal via the sound pipe 7 and the metal pipe 8.

By the way, noise caused by the external lead wire 11 (for example, friction noise between the lead wire 11 and clothing)
The vibration is primarily absorbed by the combination of the mass of the outer body 4 and the elasticity of the external lead wire 11.
Further, noisy vibrations directly applied to the outer body 4 (for example, wind noise, vibrations caused by hair) are absorbed by the combination of the elasticity of the external damper 3 and the mass of the insert body 1.

Furthermore, the vibration of the speaker itself caused by driving the speaker 5 is primarily absorbed by the combination of the high elasticity of the speaker damper 6 and the mass of the outer body 4, but vibrations that are not sufficiently damped even with this, Further, the combination of the elasticity of the external damper 3 and the mass of the insert body 1 provides secondary damping, thereby preventing noise vibrations from propagating to the conversion element 2.

Yet another vibration transmission path, that is, the sound pipe 7, the metal pipe 8, and the sound pipe damper 9, is achieved by a combination of the high elasticity of the sound pipe 7, the mass of the metal pipe 8, and the high elasticity of the sound pipe damper 9. Anti-vibration. In addition, the sound pipe 7 and the metal pipe 8
Vibrations excited by sound energy passing through the sound pipe damper 9 are absorbed by the combination of the high elasticity of the sound pipe damper 9 and the mass of the metal pipe 8.

Therefore, since the conversion element 2 detects only the vibration directly applied to the insert 1, it is possible to prevent howling, which is an obstacle to communication in a two-way communication system, or to prevent startup errors in a communication system using a voice activation method using a single carrier frequency. It can be prevented.

Note that the vibration-proof structure of the speaker 5 can also be provided with an extremely thin rubber film.

As described above, according to the present invention, a speaker is mounted inside an ear microphone to which a conversion element is attached, and the speaker is mounted so as to float using a material with a very high elastic modulus, so that the vibrations of the speaker are transmitted to the conversion element. Therefore, there is no problem of howling during two-way communication using two carrier frequencies.
Furthermore, in the case of a device that uses a single carrier frequency and performs two-way communication using an automatic transmission/reception switching system, it has the advantage that the communication does not malfunction and can be switched only by the voice signal of the wearer.

[Brief explanation of the drawing]

The figure is a cross-sectional view showing an embodiment of the intra-external auditory canal two-way communication device according to the present invention. 2... Conversion element, 5... Speaker, 7... Sound conduit.

Claims (1)

[Claims] 1. A conversion element that is inserted into the ear canal and converts bone conduction audio signals into electrical signals, a speaker that is mounted in a floating state using a material with a high elastic modulus, and a sound that emits the sound from the speaker into the ear canal. A two-way communication device within an ear canal characterized by having an integral structure with a conduit.