GB574734A - Improvements in or relating to work holding and stock feeding fixture for broaching machine - Google Patents

Abstract

574,734. Broaching. LAPOINTE MACHINE TOOL CO., Ltd. (Lapointe Machine Tool Co.). Feb. 15, 1944, No. 2805. [Class 83 (iii)] Bar feeds.-A work-holding and stock-feeding fixture for broaching-machines comprises a base, a support slidable forward and rearward on said base to move the work into and away from the broaching-position, a stock-holding and feeding carriage slidable longitudinally on said support, means to move the carriage longitudinally on said support and means corelating the movements of the support and carriage, whereby upon longitudinal stockfeeding movement of the carriage, the support and carriage are moved to the broaching position, whilst during the non-feeding movement of the carriage the support and carriage are moved away from the broaching position. The invention is described as applied to a machine having a vertically operating broach B for cutting teeth in superposed strips of band-saw stock S, which is fed forward stepby-step between guide rolls 30, 31, 32, 33. Opposite the broach B the work may be clamped by a member 60 mounted on the carriage 12 and operated by a lever 62 formed with a cam block 65 adapted to be actuated by a cam block 66 at the end of the rod 67 of a piston 68. Before the work reaches the broach, it may be clamped by means of a lever 52 mounted on a support 11 and operated by a piston in a cylinder 56. The carriage 12 may be moved longitudinally on the support 11 between adjustable stops 25, 26 and 27 by means of a piston 15. As the carriage moves to the left, as shown in Fig. 1, a cam slot therein, into which projects a roller carried by a pin fixed in the base 10 and passing through a transverse slot 22 in the support 11, causes the support and carriage to move away from the broach B, together with the stock S. When the broach has completed a downward cutting stroke, fluid operates the piston 15 to move the carriage 12 to the left and both the carriage and support move rearwardly away from the broach. At the same time, the clamp 60 is released. At the -end of the carriage movement to the left, the clamp 60 is again operated to grip the work, the clamping lever 52 is released and the carriage is moved back to the right, carrying with it the stock S, after which the clamping lever 52 is again engaged. During the idle movement of the carriage, the broach moves upwards and is ready for another cutting stroke when the carriage has returned to the right and the support 11 has moved rearwardly to feed the stock up to the broach.