GB154037A - Improvements in and relating to automatic punching machines - Google Patents

Abstract

154,037. Drewes, J. Oct. 8, 1919 Punching; punches.-In a gang punching-machine each of the punches 15 is carried in a separate holder 14 pivoted to the head 12 and capable of being swung out of the way into the inoperative position automatically and periodically or by hand. Each punch-holder 14 is connected by linkwork 18, 20 to levers 19, 21 normally loose but capable of being fixed bv set-screws on shafts 16, 17. The shaft 16 may be operated when required by a handle h to move and hold the punches connected thereto in or out of operative position, and the shaft 17 may be oscillated to move the punches connected thereto by a spring 17<a> and cam 24 rotated by a ratchet 26 and a pawl 27 which may be thrown out of action but is normally oscillated through an arc, adjustable by a screw 31, by the sliding block 11 of the eccentrics 10 which reciprocate the head 12. The shaft 3 is driven as shown through a clutch 8, and carries an adjustable-throw crank 39 which acts through the ratchet 35, pinions 33, 33<a>, and rack bars 32, 32<a>, to feed the work w intermittently below the punches. The work is held down by rollers 47 on adjustable bellcranks 46 and positioned by taper pins 52 operated by cams 51 on the shaft 3. To avoid all the punches acting on the work simultaneously, they may decrease in length from the centre and to alter the pitch laterally the holders 14 are replaced by others of a different width.