Miniature buzzer
US4251807A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 8, 1979 |
| Grant date | Feb 17, 1981 |
| Priority date | — |
| Expiry date | Mar 8, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10K11/04
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
A miniature buzzer for a pocket pager and the like is provided. The buzzer includes a support member in the form of a cylindrical collar having a bore extending therethrough. The bore is stepped with the step defining a knife edge. A pole piece surrounded by a coil and ring magnet extends toward the step. The ring magnet and a central portion of the pole piece define a plane spaced apart from the step. A diaphragm, backed by a magnetic armature seats on the knife edge for attraction/repulsion toward/from the pole piece. The coil is driven by an oscillator extends from the collar. The assembly is contained within a housing the volume of which is also tuned to the oscillator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.