GB570229A - Improvements in machines for grinding drills and similar tools - Google Patents

Abstract

570,229. Sharpening drills &c. FIELDING, D. T. E. May 15, 1944, No. 4817. [Class 60] A machine for sharpening twist drills comprises means for supporting and passing the drill across the vertical face of a grinding- wheel, the means consisting in a bracket mounted on a vertical pivot on a second bracket which is mounted in turn on a vertically adjustable horizontal pivot, the grinding- wheel being mounted on an adjustable slide ; devices for positioning the drills are provided. The drill A<1>, Fig. 1, is carried on fixed and adjustable supports E<1>, E<2> on a bracket E which is mounted on a vertical pivot f, on a second bracket F mounted on a horizontal pivot h adjustable vertically by a hand-set cam h<6>. The bracket E is held in an adjusted position round the pivot f by a set-screw &c. f, and when in position for thinning, the point of the drill is engaged by a stop d to prevent movement across the face of the wheel. The wheel A is driven by a motor B carried by a slide C adjusted by a hand-operated cam c<1> engaging an adjustable stud c<5>. The drills are correctly placed in the supports by a peg e<7>, or by a notched member e<8>, Fig. 12. Small drills may be mounted in a chuck and are centred by means of a device comprising plates k<1>, k<2>, Figs. 7, 7a, with their operating faces k<3>, k<4> in line.