Diaphragm of dynamic microphone
Patent 5148492 Issued on September 15, 1992. Estimated Expiration Date: 
March 14, 2011. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
March 14, 2011. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesBoron coated diaphragm for use in a loud speaker Acoustic diaphragm with polyurethane elastomer coating Speaker Loudspeaker having a two-part diaphragm for use as a car loudspeaker Audio transducer with controlled flexibility diaphragm Patent #: 4903308 InventorsAssigneeApplicationNo. 669035 filed on 03/14/1991US Classes:381/177, Dynamic (e.g., magnetic)181/166, With damping means181/170, Laminated type381/398, Having diaphragm support feature381/423Specified diaphragm shape or structureExaminersPrimary: Ng, Jin F.Assistant: Le, Huyen Attorney, Agent or FirmForeign Patent References
International ClassH04R 025/00Foreign Application Priority Data1990-05-22 JPAbstractThere is a dynamic microphone comprising: a diaphragm which can vibrate by an acoustic wave and a voice coil which is joined to the diaphragm so as to transverse a magnetic field formed by the magnet and can vibrate integratedly with the diaphragm, wherein a number of peripheral treatment agents for damping are coated in a dot shape or a discontinuous stripe shape at intervals onto either one of the front surface and the back surface of the portion of the diaphragm excluding the center dome. With the above construction, a change in stiffness of the diaphragm by the peripheral treatment agents is extremely reduced, it is prevented that the diaphragm resonates at a special frquency, a sudden attenuation of the low frequency limit is prevented, and a low sound can be also certainly collected. | |
