GB618399A - Improvements in guillotines and like cutting machines - Google Patents

Abstract

618,399. Guillotine machines. DORIN, A. Nov. 4, 1946, No. 32678. [Class 31(i)] In a guillotine cutting machine, operated by fluid pressure, the two ends of the knife have direct and substantially vertical connection with two cylinders arranged so as to produce different speeds of descent of the two ends. The knife preferably starts its descent with its cutting edge inclined to the top-plate and finishes with its edge parallel to the top plate, and the cylinders are arranged so that they apply an equal force to each end of the knife. Figs. 1 and 3 show the machine in front and side elevation respectively and Fig. 4 is a cross section through the knife and operating cylinders. In Figs. 1 and 3 the top plate 10, supported by a box structure 11 at its front end and a pair of pillars 12 at its rear, has a slide 22 with vertical ribs 23 which feeds the work between a pair of guides 17 to the knife. The slide is connected to an endless chain 26 and can be moved by the hand wheel 38 whose spindle carries a bevel wheel 39 which meshes with another bevel connected to wheel 28 which drives the chain. The slide can also be power operated; chain-wheel 28 is fast with spindle 29 and gear 31. the latter can be connected to gear 34 by raising hand lever 33 which is pivoted about the axis of gear 34 and carries an idler gear 32 so that gear 32 transmits the drive from gear 34 to gear 31; the gear 34 is driven from motor 37 by belts 36 and a worm-reduction gear in gearbox 30. The slide 22 can be locked in any position by moving lever 70, which is connected to a long wedge member (not shown) disposed between the slide 22 and its guide members. The knife 19 is carried by holder 18 whose two ends are connected to pistons 46 and 49 working in cylinders 44, 45 of different bore and stroke to produce the desired different speed of descent of the two ends of the knife. To ensure the application of equal force to each end of the knife, the flow of fluid to cylinder 44 may be throttled. Pressure is obtained from pump 43 driven from motor 37 through belts 36 and 41, and fluid is distributed by valve 86 either through pipes 89 to the two cylinders to lower the knife, the supply to cylinder 44 being throttled by valve 87, or through pipes 90 thence through ports 53 and tubes 54 into the hollow piston rods 47, 50 to raise the knife. The distributing valve 86 may be operated manually or automatically by connections (not shown) with the treadle 55. Depression of the treadle 55 lowers the presser weight 20, Fig. 4, on to the work prior to cutting, and raises the guard rail 64. The position of slide 22 is indicated by a calibrated band 84, Fig. 1, which moves past a window 74 and is driven by shaft 78 and bevel gears 79 from the shaft 29 which drives the slide.