GB527959A - Improvements in or relating to feeding devices for machine tools - Google Patents

Abstract

527,959. Grinding drills &c. DECKEL, F. April 24, 1939, No. 12333. Convention date, June 1, 1938. [Class 60] [Also in Group XXII] A feed device for a machine in which the work piece such as a stepped drill 13 has a combined rotary and axial movement, comprises a cam disc 21 mounted on the work holder 5, and located in a plane parallel to the work axis, the cam being rotated from the work spindle through bevel gearing 9, 11 and having portions of different curvature so that it may coact with a stationary abutment arm 27 to impart different axial movements to the work according to the part of the cam which is operative. The work may be set by a scale 15 to change the face to be ground. The cam may be adjusted by disconnecting it from its shaft 19 and may be graduated, Fig. 2, so as to indicate the relief angles obtained with work of different diameters, when different parts of the curve, corresponding to the radial lines a, are used. In grinding a relieved surface such as 39 by a stationary grinding-disc 41 the abutment 37 is set to the required point on the disc according to the diameter of the work and relief angle required and the abutment then placed in contact with the roller 25 engaging the disc, the work being set so that the wheel engages the end of the surface 39. The work is then turned thus rotating the cam disc and causing the work to move forward until a limiting abutment 45 is reached. To change the work position to grind the next cutting face, the knob 15 is used. If another work surface such as 43 is to be relief ground, the disc is reset according to the new diameter and relief angle.