Mine firing control system
US4185552A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 16, 1945 |
| Grant date | Jan 29, 1980 |
| Priority date | — |
| Expiry date | May 16, 1965 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF42B22/04
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
1. In a mine firing control system of the character disclosed, the combination of a mine firing control circuit including a plurality of electron discharge devices each of which is adapted to be rendered conducting when the bias voltage thereon is elevated to a predetermined value, circuit means including a first normally conducting electron discharge device for applying said bias voltage to said plurality of electron discharge devices, circuit means including a second normally non-conducting electron discharge device adapted to render said first electron discharge device non-conducting as said second electron discharge device is rendered conducting, means controlled by said mine firing control circuit for rendering said second electron discharge device conducting as the control circuit operates, and means for operating the control circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.