Polar positioning device for rock drills

Claim 1

A POLAR POSITIONING DEVICE FOR ROCK DRILLS FOR POSITIONING A ROCK DRILL TO A PLURALITY OF ALTERNATIVE DRILLING POSITIONS ACCORDING TO A POLAR COORDINATE SYSTEM, SAID POSITIONING DEVICE COMPRISING A SUBSTRUCTURE HAVING COAXIAL JOURNALS THEREON SPACED IN THE LONGITUDINAL DIRECTION THEREOF, A BASE FRAME PIVOTALLY MOUNTED ON SAID JOURNALS ABOUT AN AXIS EXTENDING LONGITUDINALLY OF SAID SUBSTRUCTURE AND DEFINING THE POLAR AXIS OF SAID COORDINATE SYSTEM, AN ELONGATED FEED SHELL FOR LONGITUDINALLY MOVABLY CARRYING A ROCK DRILL THEREON HAVING FEEDING MEANS THEREON FOR FEEDING AND RETRACTING SAID ROCK DRILL ALONG SAID FEED SHELL, A LINK SYSTEM LINKED BETWEEN SAID FEED SHELL AND SAID BASE FRAME FOR TRANSLATORY MOTION OF SAID FEED SHELL TRANSVERSELY THERETO AND TO SAID BASE FRAME IN A PLANE INCLUDING SAID AXIS SAID LINK SYSTEM INCLUDING A PAIR OF ELONGATED LINK FRAMES IN SAID PLANE DISPOSED CROSSWISE AND PIVOTED TO ONE ANOTHER IN SCISSORS MANNER ABOUT A CENTRAL PIVOT, FIRST POWER MEANS ON SAID SUBSTRUCTURE AND OPERATIVELY CONNECTED TO SAID BASE FRAME FOR DEFINING THE ANGULAR POSITION OF SAID LINK FRAMES AND FEED SHELL ABOUT SAID AXIS, AND SECOND POWER MEANS OPERATIVELY CONNECTED TO SAID LINK FRAMES FOR MOVING SAID LINK FRAMES AND TRANSLATING SAID FEED SHELL THEREON TO THE DESIRED POSITION IN SAID PLANE RELATIVE TO SAID BASE FRAME THEREBY TO DEFINE THE RADIUS VECTOR IN SAID POLAR COORDINATE SYSTEM.