Mine roof support control systems
US4050256A · kind A · utility
8Cited by
7References
16Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 25, 1975 |
| Grant date | Sep 27, 1977 |
| Priority date | — |
| Expiry date | Nov 25, 1995 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21D23/12
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A control system for a self-advancing mine roof support includes function selection hydraulic valve means responsive to coded electrical signals from remote means for selecting a desired function, and means for comparing the coded signals with other signals representing the instantaneous function state of the valve means. Usually each of a plurality of supports incorporates the remote means of a neighboring support.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.