GB285642A - Improvements in or relating to milling machines - Google Patents

Abstract

285,642. Abbott, G. J. Feb. 10, 1927. Milling-machines.-In a milling-machine for cutting radial grooves in plane or conical discs -such as are used for the opposing faces of expanding pulleys, the work is oscillated relatively to the cutter about its centre and is simultaneously reciprocated perpendicularly to the length of the groove being cut and fed parallel to the groove. The cutter C is carried by a stationary shaft C<1> and the work B is mounted on a rotary table A which is inclined so as to make one generator of the cone horizontal, the table being rotatable on a transverse slide E traversable in guides E<1> on a slide F movable perpendicularly to the slide E. In operation, the cutter is rotated by a chain T which passes over sprockets U, V and also engages a wheel M' which rotates a crank L driving connecting rods J<1>, K<1>, the former serving to oscillate, through an adjustablethrow crank J, a screw H engaging a nut on the slide E and the latter being connected at an adjustable radius to a toothed sector K engaging a pinion on a shaft P carrying a worm S meshing with a worm-wheel S<1> attached, to the work-table A. The oscillation of the table caused by the worm S is adjusted to the width of groove required in the work and the reciprocation of the slide E by the screw H is made equal to the thickness of the cutter in order to ensure both sides of the groove being truly radial, the movements of oscillation and reciprocation taking place in opposite directions. Springs E<2> serve to assist in returning the slide E and to take up backlash in the screw and nut H. The pinion on the shaft P is connected thereto by a plunger R<1> on an arm R and an index plate O to provide for spacing the grooves on the work, and the slide F is fed (by means not shown) to traverse the cutter along the groove. The cutter has a projecting part 6<2> for producing the groove and side portions for machining the surface of the work between the grooves, the profile of the part C<2> being adapted to the shape of groove required. According to the Provisional Specification one connecting rod only is employed and is attached at a fixed radius to the crank L and at an adjustable radius to the sector K.