Claims
- 1. A capacitor microphone including a unit case having a front face, a back face, and side faces; an impedance transducer or impedance converter disposed in a lower portion of said unit case; a fixed pole having a front face, a back face, and a side face, said fixed pole being disposed in a front portion of said unit case, the fixed pole being electrically connected to said impedance transducer; a diaphragm extended over said fixed pole, said diaphragm vibrating by the electric acoustic energy of propagating external sound; opposite side faces of the unit case having an edge portion at lower portion thereof, the edge portion begin formed with a U-shaped bend; a circuit board having a front face, a back face and side faces, the back face of the circuit board being supported by the U-shaped edges of the unit case; an impedance transducer mounted on said circuit board; a support member extending from the front face of said circuit board forward, and contacting an inner face of side faces of the unit case, the support member having a concavity at the top end so that said fixed pole fits in the concavity, a top end face of the support member being at the same level as a front face of the fixed pole; a holder ring for holding said diaphragm on a back face thereof, a first elastic member mounted between the back face of the unit case and the front face of the holder ring; a second elastic member mounted between the back face of the diaphragm and the top end face of the support member or the front face of the fixed pole; and a third elastic member mounted between the back face of the circuit board and the end of the U-shaped edge.
- 2. The capacitor microphone of claim 1, wherein said first elastic member or a second elastic member has a plurality of protrusions arranged on at least one of the upper and low surfaces thereof at predetermined intervals.
- 3. The capacitor microphone of claim 2, wherein said first and second elastic members have a certain stiffness, the stiffness of the first and second elastic members being set in accordance with a ratio of the mass of said diaphragm to the mass of said electric acoustic transducer, a vibration system of said diaphragm having the same resonance frequency as that of a vibration system of said transducer unit.
- 4. The capacitor microphone of claim 3, wherein said third elastic member has less stiffness than that of the second elastic member.
- 5. The capacitor microphone of claim 2, wherein said third elastic member has less stiffness than that of the second elastic member.
- 6. The capacitor microphone of claim 1, wherein said first and second elastic members have a certain stiffness, the stiffness of the first and second elastic members being set in accordance with a ratio of the mass of said diaphragm to the mass of said electric acoustic transducer, a vibration system of said diaphragm having the same resonance frequency as that of a vibration system of said transducer unit.
- 7. The capacitor microphone of claim 6, wherein said third elastic member has less stiffness than that of the second elastic member.
- 8. The capacitor microphone of claim 1, wherein said third elastic member has less stiffness than that of the second elastic member.
Parent Case Info
This appln is continuation of Ser. No. 08/950,881 filed Oct. 15, 1997 now U.S. Pat. No. 6,130,952.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
5272758 |
Isogami et al. |
Dec 1993 |
A |
6130952 |
Akino et al. |
Oct 2000 |
A |
Foreign Referenced Citations (1)
Number |
Date |
Country |
0499237 |
Aug 1992 |
EP |
Continuations (1)
|
Number |
Date |
Country |
Parent |
08/950881 |
Oct 1997 |
US |
Child |
09/574830 |
|
US |