The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.

The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.

Date of Patent:
Jun. 30, 1981

Filed:

Feb. 14, 1977
Applicant:
Inventors:

George P Schivley, Jr, Bridgeport, WV (US);

Peter L Madonna, Dover, NJ (US);

Assignee:

Ingersoll-Rand Company, Woodcliff Lake, NJ (US);

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B23Q / ; E21C / ; F15B / ; F15B / ;
U.S. Cl.
CPC ...
173-9 ; 91318 ; 91356 ; 91433 ; 137486 ; 1374875 ; 173 19 ;
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when the drill has completed drilling, and a third position obtained automatically when the drill has been completely withdrawn.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.


Find Patent Forward Citations

Loading…