Two-stage locking push switch
US4661667A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 18, 1985 |
| Grant date | Apr 28, 1987 |
| Priority date | — |
| Expiry date | Nov 18, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H13/64
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A heart cam type locking mechanism is provided by which in response to a first push button depressing operation, a moving member is locked at a first position in a casing, the moving member is locked at a second position in response to a second push button depressing operation and the moving member is returned to its initial position in response to a third push button depressing operation. The inside of the push button is divided by a partition plate into first and second optical path spaces. A lamp is disposed in the casing so that it emits light into the first and second optical path spaces. A light shielding plate of a resilient material is disposed in the first optical path space and fixed at one end to the moving member. When the moving member is at the initial and first positions, the light shielding plate does not engage a tapered projection formed on the casing, but when the moving member is at the second position, the light shielding plate moves on the tapered projection, closing the first optical path space. First and second display portions are provided on the push button at positions corresponding to the first and second optical path spaces, respectively. When a hook sp…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.