Patent GB-500333-A (GB)
Title: Improvements in pattern grading machines
IPC: B23Q35/20
Filed: 1938-06-07
Abstract: 500,333. Pattern - grading machines. FAIRWEATHER, H. G. C. (Aktiebolaget Linham) June 7, 1938, No. 16884. [Class 97 (iii)] Two pantographs interconnecting for relative movement in two grading directions at rightangles a model holder 28, a work holder 16, a model follower 24, and a cutting tool 5, include a common motion transmission member 48 by which the relative movement may be controlled. As shown, the cutting tool 5 is fixed on the stand 1, the work holder 16 and model follower 24 are relatively adjustable but normally move together on a slide movable in two perpendicular directions, and the model holder 28 is angularly adjustable on a slide 37, Fig. 15, running in the direction of the arrow b on a slide 32 which in turn runs in the direction of the arrow a on the stand 1. The elements 16, 24 are connected to the model holder 28 through the universal joint 51, telescopic rod 48, " length pantograph lever " 68, and " width pantograph lever" 116. The lower end of the rod 48 is universally connected to the slide 37 by a system of forks such that movement of the follower 24 in the direction b rocks the rod 48, fork 53, fork 111, and lever 116 about the axis 112-113. Similarly, movement of the follower 24 in the direction of the arrow a rocks the lever 68 through the rod 48, fork 59 and telescopic rods 60, 61. The levers 116, 68 rock about a pivot 150 normally fixed to the slide 32 and a pivot 71 normally fixed to the stand 1 respectively. Thus rocking of the rod 48 causes the slide 37 to run along the slide 32 and the latter to run along the stand 1 so that movement of the follower 24 is accompanied by movement of the model being followed. The consequent movement of the work holder 16 causes an enlarged or reduced copy to be cut out by the cutter 5. The scale of enlargement is varied by adjusting the positions of the pivots 150, 71. The pivot 150 is carried by a slide which is adjusted in a frame 119, running on the slide 32, by a screw 120, Fig. 1, and handle 121. The latter has a pin adapted to engage in one of a number of holes corresponding to the different sizes of enlargement and spaced around a disc 122, freely mounted on the screw 120 and adapted to be adjusted by gearing 95 and the quick thread screw 123 in accordance with the magnitude of certain lines in the model. This latter adjustment is effected by a slide 124 engaging the screw 123 and caused to run in the frame 119 by a member 99 which is clamped at the required setting on a graduated lever 103 pivoted at 150 and having at the other end a sliding pivot connection with the frame 119. The pivot 71 may be similarly adjusted in a frame 75 running on the stand 1. A clamp 132 clamps either a flange 131 of the slide 37 or the frame 119 to a flange 126 of the slide 32. A similar clamp clamps either a flange 80 of the slide 32 or the frame 75 to a flange 36 of the stand 1. When the slides 32 and 37 are clamped, the frames 75, 119 are free to run and the pantograph mechanism is inoperative so that a 1 : 1 reproduction occurs. To enable parts of the model, e.g. seams of shoe uppers, to be reproduced without enlargement, a single device for effecting corrections in both grading directions is provided. For this purpose, the universal joint 51 is connected to the work holder 16 and model follower 24 by an adjustable crank arm, the length of which may be adjusted to the width of the part to remain constant by the knob 216 and the direction of which may be adjusted by the hand wheel 205.