Automatic control system for rock drills
US4275793A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 14, 1977 |
| Grant date | Jun 30, 1981 |
| Priority date | — |
| Expiry date | Feb 14, 1997 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/7761
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A rock drill feed system moves a drill toward and away from a wall with a reciprocating hydraulic motor powered by pressurized fluid. The pressurized fluid is controlled by a movable control valve that has a first position obtained manually to move the drill inwardly to drill, a second position obtained automatically when the drill has completed drilling, and a third position obtained automatically when the drill has been completely withdrawn. The sensing of the location of the drill to position the control valve is accomplished by measuring the pressure and flow rate of the hydraulic fluid delivered to the motor with pressure responsive switches. When the pressure exceeds a preselected level and the flow rate drops below a preselected level, the two pressure switches close to produce a signal that moves the valve to another position.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.