Machines for grinding the points of drills

Claim 1

A MACHINE FOR GRINDING THE POINTS OF DRILLS COMPRISING A ROTATABLE GRINDING WHEEL HAVING A GRINDING FACE, A PIVOT BLOCK ADAPTED TO ROTATE ABOUT AN AXIS DISPOSED IN THE PLANE CONTAINING THE GRINDING FACE, MEANS FOR ADJUSTING THE POSITION OF THE PIVOT BLOCK SO THAT ITS AXIS CAN BE ARRANGED IN THE PLANE CONTAINING THE GRINDING FACE, A CENTERING VICE MOUNTED IN THE PIVOT BLOCK AND HAVING JAWS MOVABLE TO GRIP THE LAND OF A DRILL DURING A GRINDING OPERATION, A CHUCK ADAPTED TO RECEIVE A DRILL TO BE SHARPENED AND TO GRIP THE DRILL BY THE LANDS, THE SAID CHUCK BEING CARRIED BY THE PIVOT BLOCK, THE LINEAR AXIS OF THE SAID DRILL, WHEN THE POINT OF THE DRILL IS PLACED BETWEEN THE JAWS OF SAID CENTERING VICE, FALLS IN A PLANE IN WHICH THE AXIS OF THE SAID PIVOT BLOCK IS LOCATED, MEANS FOR ROTATING THE CHUCK ABOUT THE AXIS OF A DRILL CONTAINED THEREIN, MEANS FOR ADJUSTING THE POSITION OF THE CHUCK LONGITUDINALLY OF THE AXIS OF THE DRILL CONTAINED THEREIN WITHOUT ALTERING THE RELATIVE POSITIONS OF THE AXIS OF THE PIVOT BLOCK AND THE PLANE CONTAINING THE GRINDING FACE, A DRILL SETTING FINGER WITH WHICH A DRILL HELD IN THE CHUCK CAN BE ENGAGED TO DETERMINE THE POSITION OF THE DRILL IN THE CHUCK AND MEANS PERMANENTLY MOUNTED ON THE PIVOT BLOCK FOR TRIMMING THE GRINDING FACE, THE SAID MEANS BEING ADJUSTABLE INTO THE SAID PLANE WHEREBY, AS A RESULT OF A TRIMMING OPERATION, THE AXIS OF THE PIVOT BLOCK IS AUTOMATICALLY RETAINED IN THE PLANE CONTAINING THE GRINDING FACE.