| 摘要 |
PROBLEM TO BE SOLVED: To provide a condenser microphone unit capable of securing a shield effect against an external electromagnetic wave by securing ground conduction between a diaphragm ring and a printed board through a metal case. SOLUTION: The metal case 22 comprises a case body 27, an eaves 28, and a diameter-increased holding portion 29 in one body. The printed board 73 can be stored and held in the diameter-increased holding portion 29 while caulking pressure is generated on the side of the eaves 26 so that the printed board can be disposed in the metal case 22 in a sealed state by large caulking pressure. Consequently, the printed board 73 can give a condenser microphone unit 11 the superior shield effect against an external electromagnetic wave by securing the ground conduction to the side of the diaphragm ring 33 through the metal case 22 while closely contacting with a caulking portion 25. COPYRIGHT: (C)2008,JPO&INPIT
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