Electromagnetic induction coil antenna
US4489330A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 22, 1982 |
| Grant date | Dec 18, 1984 |
| Priority date | — |
| Expiry date | Sep 22, 2002 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R2225/51
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The invention relates to an electromagnetic induction coil or antenna device embedded in hearing aids or radio sets for receiving sound signals or carrier signals generated by a primary electromagnetic induction coil which is laid down in the room. A plurality of coils each one end of which is commonly connected and each other end of which extends outwardly from the one end so as to be uniformly arranged in a space and a phase selector connected to the coils operates, as a mercury switch, to pick up positive phase component output signals which are induced in at least any of the coils. The coils and the phase selector are fixedly built in the body of a hearing aid, etc. so that the corresponding coil and conduit in which a suitable quantity of mercury is charged may be paralleled to each other and so on, thereby to obtain a constant output sound pressure irrespective of the posture of a person wearing a hearing aid or enjoying television.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.