Patent GB-190925872-A (GB)
Title: Improvements in Printing Plate Shaving Machines.
Inventor: LAKE HAROLD WILLIAMSON
IPC: B23D1/02
Filed: 1909-11-09
Granted: 1910-05-19
Abstract: 25,872. Lake, H. W., [Cottrell & Sons Co., C. B.]. Nov. 9. Printing-surfaces; make-ready arrangements.-A machine for shaving the backs of printing-plates is constructed with a reciprocating bed, which is automatically stopped and braked at the rearward and forward limits of movement, or manually stopped at desired intermediate positions. The knifecarrying head is automatically raised and lowered at the rearward and forward positions of the bed, and can be manually raised as desired, and the knifecarrying head is so arranged as to obviate lost motion, and the knife is capable of a fine adjustment. As shown, the plate is carried by a bed 4 driven by a rack 5, pinion 6, and worm gearing operated by a reversing electric motor 11, controlled by a lever 15 which operates an electric controller 20. The bed is started from the position shown by full lines in Fig. 1 by moving the handle 15 to the left, and the bed is moved rearwards under a knife 23, Figs. 1 and .6, which is adjustably secured by screws 25, 26 in a member 24, also adjustable in a head 27. The member 24 is adjusted by means of two screws 29, freely mounted in recesses in the head 27, and engaging screwed lugs on the member 24. Springs 35, embracing the screws, serve to prevent lost motion. The screws are operated by means of spur-wheels actuated by a hand-wheel 41, or, when a fine adjustment is required, by means of worm gearing comprising a detachable worm operated by a crank-handle 46, an index and scale 47 being provided to facilitate adjustment. After adjustment, the member 24 is held in position by bolts 48 and locking-plates 49, as shown in Fig. 8. At the front and rear of the knife 25, pressurerolls 104, 105 are arranged, adjustable by means of nuts 110, 111, as shown in Fig. 4. As the bed 4 reaches its rearward position, a lug 71, Fig. 1, on the bed engages an arm 75 connected by links to an eccentric shaft 52, and eccentrics 53, on this shaft, are operated to allow vertically - guided frames, secured to the head 27, to rise under the action of springs, so as to raise the knife from the work. On the return movement of the bed, the shaft 52 is operated by an adjustable stop 72, which acts on an arm 77 of the link-mechanism, and this causes the knife to be lowered at the end of the return movement of the bed. The downward movement of the head 27 is limited by adjustable bolts 112 in uprights 28 of the frame, and a projection 114 of the head 27. The shaft 52 can be operated by a hand-lever 69 to raise the knife whenever desired ; and a connecting-link 84 between the lever 15 and arm 75 causes the motor to be stopped simultaneously. A slot in the link 84 permits the lever 15 to be actuated to stop the bed in intermediate positions. The driving-mechanism is automatically stopped by the action of fixed and adjustable lugs similar to the lugs 71, 72, which at the required times actuate a guided rod connected to an arm 95, Fig. 6, fixed to the rock-shaft 16 on which the lever 15 is mounted, this arm also being arranged to actuate a rock-shaft 92 on which is a double cam 90, Fig. 4, which controls a lever 89 fixed to the band 88 of a brake 87 on one of the driving-shafts 10. The lever 15 is moved to the right to reverse the motion of the bed ; and the bed is automatically stopped and the knife lowered at the end of the forward movement of the bed.