JP2809939B2 - Microphone device - Google Patents

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 radio telephone, a small radio telephone and the like.

[0002]

2. Description of the Related Art In general, a small radio such as a portable radio telephone uses a 1/4 wavelength antenna, so that a large high-frequency current also flows through the housing during transmission, and the microphone device of a transmitter is The microphone element is provided with a shield as shown in FIG. 3 in order to exert a bad influence such as inducing noise. In FIG. 3, reference numeral 1 denotes a printed circuit board on which electronic components are mounted to form an electronic circuit such as a wireless transceiver, and 2 denotes a front case of a wireless telephone case.
Is perforated. 4 is a microphone element, 14 is a bushing for protecting the microphone element 4 and forming an air chamber and an opening for determining frequency characteristics, and 15 is for covering the outside of the front case 2 and electromagnetically shielding the microphone element 4. A wire mesh 16 is a front cover which covers the front surface of the microphone element 4 and is made of non-woven fabric. Reference numeral 17 denotes a hole of a terminal connection portion of the microphone element 4 provided on the printed circuit board 1.

FIG. 4 is an exploded view of the microphone device shown in FIG. 3, in which a bushing 14 is attached to the microphone element 4,
A wire net 15 for electromagnetic shielding is placed over this, and the printed circuit board 1 is integrally connected to the printed circuit board 1 by a terminal of the microphone element 4 and the wire net 15 and the front cover 16 are used as a front cover of the microphone device. 2

[0004]

However, the structure of the above-mentioned microphone device is complicated, the number of parts is large, and there are drawbacks that a considerable number of steps are required for assembly.

The present invention solves such a conventional problem, and has a simple structure and is effective in preventing occurrence of operation failure such as noise received by a microphone device due to transmission output and howling caused by vibration propagation from a receiver. It is an object of the present invention to provide an inexpensive and excellent microphone device with a reduced number of manufacturing steps.

[0006]

According to the present invention, in order to achieve the above object, a microphone element is housed in a container formed of conductive rubber and having a function as a bushing.

[0007]

According to the present invention, since the microphone element is housed in the conductive rubber container, the capacity becomes a conductive bushing, and the printed circuit board and the front case of the housing are elastically pressed. Good shielding, both acoustically and electromagnetically, is provided and assembly is simplified.

[0008]

FIG. 1 shows an embodiment of the present invention. FIG.
In the figure, reference numeral 1 denotes a printed board on which terminals of the microphone element 4 are soldered through two holes 1a and 1b. Reference numeral 2 denotes a front case of the housing, and 3 denotes a mouthpiece, and a hole is formed in the front case 2 of the housing. Reference numeral 5 denotes a front cover, which is made of a wire mesh and a non-woven fabric, and provides the microphone element 4 with waterproof and electrical shielding effects. Reference numeral 6 denotes a conductive rubber bushing (container) which electromagnetically and acoustically shields the microphone element 4 using conductive rubber. Reference numeral 7 denotes an air chamber, and a microphone element 4
And a front cover 5. The air chamber 7 allows the frequency characteristics and sensitivity of the transmission microphone to be adjusted to the front case 2 of the housing.
Can be adjusted together with the transmission hole 3. The conductive rubber bushing 6 holds the microphone element 4 and is mounted so as to be sandwiched between the printed circuit board 1 of the wireless device and the front case 2 of the housing. The opening of the microphone element 4 is attached to the front case of the housing. 2 so as to prevent the sound output from the receiver that flows through the inside of the wireless device housing from flowing, and to transmit the transmission sound pressure from the front surface of the transmission mouth 3 to the microphone element 4. Is formed.

In FIG. 1, the front cover 5 made of a wire mesh and a nonwoven fabric and the conductive rubber bushing 6 are separately molded and assembled. However, even if the conductive rubber bushing 6 and the front cover 5 are integrally molded. Good.

FIGS. 2A and 2B show a procedure for assembling the microphone element 4 and the front cover 5 into a conductive rubber bushing 6. FIG. FIG. 2B shows a cross section of the conductive rubber bushing 6. 2B, reference numeral 8 denotes an insertion opening of the microphone element 4, reference numeral 9 denotes an outer edge thereof, reference numeral 10 denotes a storage portion of the microphone element 4, reference numeral 11 denotes an insertion opening of the front cover 5, reference numeral 12 denotes an outer edge thereof, and reference numeral 13 denotes a front cover. 5 is a storage unit. In FIG. 2, since the conductive rubber bushing 6 has elasticity, the outer edge portion 9 is distorted by an external force to substantially increase the outer diameter of the insertion opening 8 of the microphone element 4 so that the microphone element 4 is housed in a housing 10 with the microphone element 4. Similarly, by distorting the outer edge portion 12 by an external force, the front cover 5 is inserted into the insertion opening 1 of the front cover 5.
1 to the storage part 13 of the front cover 5. The transmission microphone is constructed by assembling in this manner.

According to the above embodiment, the following effects are obtained. (1) The conductive rubber bushing 6 absorbs the reception sound leaking into the microphone element 4 from the back of the receiver (not shown) of the portable wireless telephone through the inside of the housing by the flexibility of the conductive rubber, thereby increasing the leakage acoustic resistance. Howling is prevented by the acoustic shield that is made. (2) Since the microphone element 4 is electromagnetically shielded by the conductivity of the conductive rubber, the transmission output is guided by an antenna (not shown) and the printed circuit board of the portable radio telephone to attenuate the electromagnetic wave reaching the microphone element 4. To (3) After assembling the conductive rubber bushing 6 integrally with the microphone element 4, the conductive rubber bushing 6 can be mounted on the printed circuit board by a solder bath similarly to other components, so that the manufacturing assembly is convenient. Also, when assembling the microphone element 4, the conductive rubber bushing 6, and the front cover 5, the assembling is easy and the stability after assembling is good.

[0012]

According to the present invention, as is apparent from the above embodiment, the microphone element is made of conductive rubber, wire mesh and non-woven fabric.
By surrounding it with the front cover and printed circuit board,
The number is small and the whole can be assembled as one part.
The number of man-hours required for assembly can be reduced
In addition, a large electromagnetic shield against mechanical vibration and electromagnetic wave signals
This has an effect that a cold effect can be obtained .

[Brief description of the drawings]

FIG. 1 is a side sectional view of a microphone device according to an embodiment of the present invention.

FIG. 2A is an external perspective view of a microphone element, a conductive rubber bushing, and a front cover. FIG. 2B is a side sectional view of the conductive rubber bushing.

FIG. 3 is a side sectional view of a conventional microphone device.

FIG. 4 is an exploded perspective view of the device.

[Explanation of symbols]

 4 Microphone element 5 Front cover 6 Conductive rubber bushing (container) 10 Housing for microphone element

 ──────────────────────────────────────────────────続 き Continued on front page (72) Inventor Tadashi Kobayashi 4-3-1 Tsunashima Higashi, Kohoku-ku, Yokohama-shi, Kanagawa Prefecture Inside Matsushita Communication Industrial Co., Ltd. No.3-1, Matsushita Communication Industrial Co., Ltd. (56) References JP-A-4-218997 (JP, A) JP-A-3-123153 (JP, A) Japanese Utility Model Laid-Open No. 59-61653 (JP, U)

Claims (1)

(57) [Claims] 1. A microphone element, a front cover made of a wire mesh and a non-woven fabric, having a waterproof and electric shielding function for the microphone element,
The microphone element and the front cover are inserted and housed in the two openings, respectively, and one of the openings into which the front cover is inserted is in close contact with the mouthpiece of the front case of the housing. A microphone device comprising: a conductive rubber sandwiched and held by a printed circuit board in a housing.