Patent GB-594596-A (GB)
Title: Improvements in or relating to engraving machines
IPC: B44B3/00
Filed: 1945-03-21
Abstract: 594,596. Engraving-machines. BACHMANN. O. March 21, 1945, No. 7182. [Class 100 (ii)] In a machine for engraving line patterns on metal, glass &c., e.g. for the production of etched plates for printing bank notes, wherein a work-support and a stylus are relatively movable to trace figures on the work, the movement of the stylus is effected from a rotary shaft carrying a slide adjustably mounted and adapted to drive a member in a circular path, the movement of the member being transmitted in whole or in part to the stylus, and the worktable is displaced at a controllable rate. As shown, a plate coated with wax is clamped on a circular'table 12, Fig. 2, angularly adjustable in an annular support 8, Fig. 1, keyed to a rotary shaft 9, and a stylus 163 is carried by a slide 7, which moves in guides on a crossslide 3 mounted on a table 1 and is actuated by a pendulum 120 having a gyratory motion. The pendulum is carried by a support 100 movable in guides 104 under the control of an annular template 17 fixed' outside the member 8, whereby wavy &c. effects may be produced. The shaft 9 is rotated from a motor 19 through change-speed gearing comprising pinions 28, Fig. 10, any one of which can be coupled to a rotary shaft 26 by a spring- pressed key 39 adjustable by means of a rod 40, pinions 44 on a shaft 54, intermediate pinions 43, gears 55, 56, movable along the shaft 54 and co-operating gears 60, 61, fixed to a shaft 62 driving the shaft 9 by a worm 63 and wormwheel 64. The pendulum 120 slides within a sleeve 119, Fig. 5, terminating in a flat part 116 pivoted at 124 in the bifurcated end of a screwthreaded rod 115 slidable within a sleeve 114 connected by an universal joint 111...113 to a block 110 slidable in guides in a chuck 108 driven by gearing from a shaft 97, Fig. 1, rotated from the shaft 26, Fig. 10, through change-speed gears 25, 27, and 81, 82, forward and reverse gear mechanism 83, 84, and 90, and further change-speed gears 93, 94 and 95, 96, Fig. 1. The part 116, Fig. 5, which has prongs 117, 118, co-operating with a nut member 122 on the rod 115 has a universal-joint mounting in a sleeve 128 angularly adjustable or mechanically oscillated in a block 129 mounted in a bearing 131, Fig. 1, carried by arms 132 reciprocated vertically by a rod 136 connected by a radially adjusted crank-pin to a disc 137 rotated by change-speed gearing 141...143. The pendulum support 100 is pressed towards the template 17 by a spring 157 and carries a roller 153 adjust able vertically by means of a screw 152. The roller 153 engages a pivoted arm 155 carrying a roller 156 engaging the template. In use, the block 110 is adjusted eccentric to a drive-shaf 107 by turning a screw 109 and, with the membe 122 clear of the prongs 117, 118, the pendulun 120 reciprocates the slide 7 and a sine curve is produced. When the member 122 is screwed right down, the pendulum has a gyratory motion whereby looped patterns are pro duced and when screwed partly down, break: are formed in the patterns. The patterns are varied as to shape, height, obliquity &c. by means of the change-speed and reversing- mechanisms and by the various adjustments The stylus 163, Figs. 1 and 2. is carried by. a bar 160 clamped to a flange 161 on the slide 7. More than one bar may be provided, or a number of stylus-holders may be mounted on a bar 165. The work-holder-may be on a double slide or on a turntable mounted on a slide. The patterns traced are generally circular : Fig. 32 shows an example. Patterns of a straight line character, such as shown in Fig. 38 are produced by replacing the work-holder 8 bv a holder on a slide which is reciprocated in guides by a pinion on the shaft 9. Patterns may be superposed.