Overhead projector
US4776688A · kind A · utility
9Cited by
3References
8Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 29, 1987 |
| Grant date | Oct 11, 1988 |
| Priority date | — |
| Expiry date | Jan 29, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B21/132
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An overhead projector having a stationary main body including a Fresnel plate, a projection unit, and a swingable member for supporting the projection unit and swingably secured to the main body. The overhead projector comprises one way clutch means through which the swingable member is secured to the main body and which is adapted to limit the swinging motion of the swingable member towards the main body.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.