GB1008241A - Improvements in machines for cutting lengths of strip material - Google Patents

Abstract

1,008,241. Cutting webs. D. BENEDICT and J. B. BELLERBY. Nov. 28, 1962 [Aug. 28, 1961], No. 30971/61. Heading B4B. A machine for cutting lengths of strip material comprises a fixed cutter-blade 2, Fig. 3, a co-operating movable blade 7, means for driving said movable blade and means for variably feeding a continuous strip of material across said fixed blade to be periodically cut by said movable blade, the outer end of the blade 7 being arrested by a nose 17, Fig. 3, as the inner end approaches the corresponding end of the fixed blade so that when the end of the blade is released after being drawn across the nose by rotation of a disc 5, the stress of a spring 15 snaps the blade down across and along the blade 2 with a scissors motion. Blade 7 which effects a shearing cut in co-operation with blade 2 is carried by an arm 6 pivoted to the disc 5 driven by a shaft 4 having a worm-wheel 2, Fig. 1, engaging a worm 23 driven by a pulley 25. A feed roller 26 is driven from the end of the worm shaft by a crank mechanism comprising a disc 28, Fig. 2, having locating apertures 29a ... 29d for a crank-pin 30 connected by a link 34 to a slotted crank 32 having an adjustable crank-pin 33 secured via a one-way clutch 31 to the roller shaft 27. As the crankpin 33 is adjustably moved nearer the axis of shaft 27 the angular displacement of the driven crank 32 and the feed-roller is increased for a given displacement of the link 34, whose stroke is adjusted by the location of the crank-pin 30 in the driving crank disc. Such adjustments determine the length of feed of the strip. The feed roller co-operates with an idler roller 36 which is adjustably spring-urged downwards by springs 40, Fig. 3, bearing on arms 38 and having adjustment knobs 41, into contact with the fed material. The arms 38 which carry the idler roller are raised for location of the material by operation of a lever 46, Fig. 1, actuating a spindle 45 bearing cams engaging push rods 44 and extensions of the arms 43. A clutch 48 is provided at the other end of the spindle 27 from the clutch 31 and is effective in the opposite direction to prevent reverse rotation of the spindle when the crank 32 is swinging rearwardly. In a modification (not shown) a pair of feed rollers 26 with the roller 36 between them are arranged so that a gear on shaft 27 engages a gear on roller 36 which in turn engages a gear on the second feed roller. Strip material may be fed from reels and cut in layers or plies, or arranged for cutting side-by-side. In a further modification (not shown) the feed roller system may be mounted on an angularly displaceable frame, to provide variable oblique cutting of the material, means being provided to enable the angular displacement of the feed while the drive shaft 27 for one feed roller does not correspondingly move, so that the roller remains at a substantially constant distance from the fixed blade. The machine may be provided with two movable blades mounted 180 degrees apart on the driving disc. The speed of the drive shaft relative to that of the disc 28 may be varied, e.g. by epicyclic gearing associated with the worm-wheel 22. The blades 2, 7 may be curved or serrated to provide curved or pinked edges on the cut portions.