GB1132341A - Improvements in or relating to guillotines - Google Patents

Abstract

1,132,341. Guillotine cutting - machines. R. D. H. THOMPSON- & CO. Ltd. 30 June, 1967 [30 June, 1966], No. 29514/66. Heading B4B. A guillotine comprises a framework 1 which supports a clamp 50 for holding the work to be cut, a knife 16, a die 9 past which the knife is moved to cut the work, and means for operating the clamp and knife in timed relation to the feed of the work, the knife and clamp being operable from a main drive shaft 40, there being strips 19 mounted so as to be movable with the knife and each arranged with a face coplanar with the cutting face of the knife and depending below the knife in such a way that, in operation, they will engage against the edge of the die so as to guide the knife relative to the die. The die is secured in an inverted channel-shaped member 7 having mounted in the channel thereof rotatable eccentric discs (12), Fig. 2 (not shown), which enable the position of the die to be adjusted. The knife is releasably secured to a support 15 having two depending strips 19 secured thereto. The support 15 is secured to the lower ends of bell-cranks 20, 21 which are pivotally secured to a strut 22, the bell-cranks being coupled to a connecting rod 25 and the upper end of the bell-crank 21 being connected to the piston-rod 26 of an air cylinder 27 so as to urge the knife to a raised, inoperative position. The pivot connections of the bell-cranks to the strut may be vertically adjustable. The support 15 is coupled by means of a slotted bar 34 to a connecting rod 36 which is coupled by arms 37, 39 on a rocker arm 38 to the main shaft 40. The clamp 50 is connected to two rocker arms 53, 61 fixed to a rocker shaft 54. A connecting rod 55 connects the arm 53 to an air cylinder and piston arrangement 56 to urge the clamp into its lowered, operative position. The arm 61 is connected to the shaft 40 by means of a two-part connecting rod 63, 64 the upper end of the part 63 being movable in a slot 65 in the arm 61 and the lower end of the part 63 terminating in a stirrup 66 within which the upper end of the part 64 is captive with the interposition of shock-absorbing cup washers 67. The lower end of the part 64 is connected to an arm 68 of the rocker shaft 38. The work is held by a gripper bar 78 secured to a slide block 79 which is movable along a slide rod 80 relative to a movable roller platform and. a stationary platform 77 towards the clamp and knife. Secured to the top of the block 79 is a pivotally-mounted stirrup which is engageable successively with each of a plurality of adjustable stops 91 to actuate a microswitch which initiates the operation of the clamp and knife. The stops are secured to a rod 90 which is tiltable about its longitudinal axis, out of the path of the stirrup 95, by means of an air cylinder and piston arrangement 93 and a bellcrank 94. If the work is not correctly positioned, interlock pawls 43 and 59 are operative to limit or prevent operation of the knife and clamp. The pawl 59 is engaged by an adjustable stop 58. The pawls are disengaged by the pistons of air cylinders 44 and 60. The pawl 59 and stop 58 may be replaced by a toggle grip clamp. Two gripper bars and slide blocks may be provided one of which is arranged to feed the work while the other returns to pick up fresh work. The gripper bars may be mounted on a carriage the speed of which is reduced as it nears a stop.