Device for generating sound waves at relatively high frequencies
US4437428A · kind A · utility
Inventor
Key dates
| Filing date | Mar 19, 1982 |
| Grant date | Mar 20, 1984 |
| Priority date | — |
| Expiry date | Mar 19, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10K5/02
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A device for generating warning signals consisting of sound waves at frequencies between 14 and 26 kHz, preferably intended to be mounted on a motor vehicle so that the device will be actuated by the wind. The device operates similar to a flue pipe and generates a subatmospheric pressure behind the sharp edge of the flue pipe. The subatmospheric pressure is created by a passage continuing to a resonant chamber, open at its rear end, the passage being larger in cross-section than the resonant chamber. The passage is formed in a body which has substantially the shape of a frustum of a cone and is formed with longitudinal through slots which extend from the passage. With this design, a subatmospheric pressure is generated which excites the pipe to vibrate even in a relatively slow wind.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.