Abstract An automatic control system for a guide shell-mounted rock drill including a control circuit having pneumatically operated valves for providing pressure fluid to the drill hammer, rotation motor and feed motor and for controlling drill hole flushing medium. Sensors mounted on the drill guide shell provide for reversal of the feed motor and reduced drill power upon reaching the forward end of the guide shell, and shutdown of the drill upon reaching the rearward end of the guide shell. The control circuit includes a series of control valves for selection, at will, by the drill operator of a particular operating sequence or condition of the drill. A control valve is included for providing an operating sequence which includes operation of the drill at reduced power for a predetermined period of time for collaring a drill hole. The control system also includes pressure proportioning valves for automatically regulating the feed motor pressure to be proportional to the drill percussion motor supply pressure.
An improved operating cycle for a rock drill to drill a hole in rock or the like comprising: providing a rock-drilling apparatus including a pressure fluid operated rock drill movably mounted on a support and operable to actuate a hollow drill steel, and a pressure fluid operated feed motor operable to feed said drill reversibly along said support, the operating cycle comprising; supplying pressure fluid to said drill and said feed motor at reduced Pressure for a predetermined period of time for collaring said hole; automatically supplying pressure fluid to said drill at substantially supply pressure at the expiration of said collaring time period and simultaneously supplying pressure fluid to said feed motor to feed said drill forwardly for drilling a hole to a predetermined depth; supplying flushing liquid to said hollow drill steel during collaring and drilling of said hole; automatically supplying pressure fluid to said feed motor to retract said drill along said support upon completion of the drilling of said hole and simultaneously supplying pressure fluid to said hollow drill steel, and upon retraction of said drill a predetermined distance along said support interrupting the supply of pressure fluid to said feed motor.
Claim 2
Dependent Claim
196 words
An improved operating cycle for a rock drill to drill a hole in rock or the like comprising: providing a rock-drilling apparatus including a pressure fluid operated rock drill movably mounted on a support and operable to actuate a hollow drill steel, and a pressure fluid operated feed motor operable to feed said drill reversibly along said support, the operating cycle comprising; supplying pressure fluid to said drill and said feed motor at reduced Pressure for a predetermined period of time for collaring said hole; automatically supplying pressure fluid to said drill at substantially supply pressure at the expiration of said collaring time period and simultaneously supplying pressure fluid to said feed motor to feed said drill forwardly for drilling a hole to a predetermined depth; supplying flushing liquid to said hollow drill steel during collaring and drilling of said hole; automatically supplying pressure fluid to said feed motor to retract said drill along said support upon completion of the drilling of said hole and simultaneously supplying pressure fluid to said hollow drill steel, and upon retraction of said drill a predetermined distance along said support interrupting the supply of pressure fluid to said feed motor.
Claim 3
Dependent Claim
57 words
The operating cycle set forth in claim 1 together with the step comprising: automatically delaying, for a predetermined time period, the supplying of pressure fluid to said feed motor to retract said drill upon completion of the drilling of said hole, and continuing the supply of flushing liquid to said drill steel during said predetermined time delay.
Claim 4
Dependent Claim
37 words
The operating cycle set forth in claim 1 wherein: the supply of pressure fluid to said feed motor during drilling of said hole is automatically maintained proportional to the pressure of said fluid supplied to said drill.