Patent GB-208000-A (GB)
Title: Improvements in metal punching machines
IPC: B21D28/26
Filed: 1922-11-29
Abstract: 208,000. Bennie, H. O. Nov. 29, 1922. Punching. - A metal punching machine is mounted on wheels and transversely movable on a wheeled carriage, which is movable longitudinally on rails, the wheels being driven so as to enable the punch to be brought into any position over a plate &c. fixed on a stationary table. The plate 1, Fig. 1, is secured to a stationary table 2 with the part to be punched overhanging, and the punching machine is mounted on wheels 4 so as to be traversed laterally on a wheeled carriage 5 itself traversed on rails 8. The die 9 is arranged on a level with the under side of the plate. The machine is driven by an electric motor 15 carried thereby, which is geared to a fly-wheel shaft 16, connected by gearing 43, 42 to the shaft 41 for operating the traversing gear and by gearing 19, 20 and clutch 29, 21 to the shaft 13 for operating the punch head 12. Lateral traverse in either direction is effected by bevel gears 44, 45 either of which is connected to the shaft 41 by a friction clutch 40 operated by a rod 36 through pivoted arms 37, 39. The bevel gears mesh with a bevel wheel 46, which is connected to the shafts of the wheels 4 by bevel gear 48, 49 and worm gear 51, 52. The longitudinal traverse of the carriage 5 in either direction is effected by bevel gears 62, 63, either of which is connected to the shaft 41 by a friction clutch 61 operated by a handle bar 54, which is secured to arms 55 on a spindle 56 connected by bevel gear 57, 58 to a spindle 59 carrying a lever 60. The bevel gears 62, 63 mesh with a bevel wheel 64 on an inclined shaft 65, which is connected by worm gear slidably feathered on one of the wheel shafts. The wheel shafts are geared together through a cross-shaft and bevel gear. The clutch 29, 21 is put into operation so as to drive the punch head by a pivoted treadle 22 provided with a rod 24 connected to an arm 25 at one end of a spindle 26, the other end of which carries a similar arm 27 connected to a plunger 28. The movable part 29 is pressed forward by springs 34 through adjustable eye bolts 33 and forks 31 and is automatically put out of action at or near the top of the stroke. When the holes in one half of the plate are completed the plate is turned round and the operation repeated. More than one machine may operate on the same half of the plate. In a modification the plate may be supported by a series of pairs of pivoted arms 75, Fig. 5, provided with projecting fingers 83 and held in the vertical position by weighted levers 82 but pressed down by the machine when it contacts therewith. The levers 82 normally rest on projections 84 on the bracket 80. The arms are connected at their upper ends by horizontal bars provided with lateral work-stops. The end of the plate is secured by a pair of clamps 85, 86 pivoted at 88 to a stationary member 77. Separate machines traversed on parallel sets of rails may thus be used so as to punch the holes in the two halves of the plate simultaneously, one or more machines being traversed on each set of rails. Multiple-punch machines may also be used and the machines may be traversed automatically step-by-step by gearing operated from the main shaft, when the holes are equally spaced from each other, so as to reduce marking of the plate.