Patent GB-891020-A (GB)
Title: Stacking mechanism
IPC: B65H29/32
Filed: 1959-11-10
Abstract: 891,020. Stacking sheets. GAUBERT, R. J. M. Nov. 10, 1959 [Feb. 25, 1959], No. 38043/59. Class 100(1) A sheet stacking mechanism comprises a plurality of parallel conveyer belts, a vacuum chamber mounted above the conveyer belts, a discharge conveyer belt extending beneath the parallel conveyer belts in the region beneath the vacuum chamber, the bottom of the vacuum chamber having longitudinal slots therein through which air tending to enter the vacuum chamber holds the sheets to be stacked against the underside of the conveyer belts for movement therewith, and blades which can be projected through the slots in the vacuum chamber for moving the individual sheets downwards away from the suction zone of the openings. The mechanism comprises side plates 11, 12 between which is secured a rectangular housing 14 constituting the vacuum chamber. The sheets are fed into the mechanism between two sets of spaced, parallel belts 24, 30 of which the former set is carried by rollers 26, 52 and the latter set is carried by rollers 32, 34, 36, 44, 46, 51, the rollers 32, 26 being driven. The lower runs of the belts 30 pass along grooves 31, Fig. 5, in the lower face of the housing 14, the outer surfaces of the belts standing proud of the surface of the housing. The bottom of the housing 14 is slotted longitudinally at 50 between the grooves 31. Suction is applied to the housing 14 through a conduit so that as the individual sheets leave the nip of the two sets of belts 24, 30 they are maintained in contact with the lower run of the belts 30 until stripped therefrom by blades 138 which move downwards through the slots 50 and deposit successive sheets in a pile on a normally stationary conveyer 150. The blades 138 are secured to the underside of a rectangular frame including members 131, 133, 134 which is movable within the housing 14. Two rails 60, 62 are mounted horizontally in the housing 14 and sleeves 64, 66 are slidably mounted thereon. Two U-shaped brackets 90, 92 are formed integrally with each sleeve and in the brackets are journalled shafts 96, 100 each of which carries a gear such as 102. The gears 102 mesh with a rack 94 which is slidable between the legs of the brackets 90, 92, so that rotation of one gear is transmitted to the other. At their inner ends the shafts 96, 100 carry crank arms 120, 122 which are also pivoted to brackets on the frame members 131, 133. At its outer end each shaft 96 carries a crank lever 104 which is oscillated through a bell-crank lever 108 and a link 106 by a cam 114 on a camshaft 56. Oscillation of the lever 104 causes the vertical reciprocation of the blades 138. The sleeves 64, 66 are reciprocated horizontally by eccentric cams (not shown) mounted on the camshaft 56 and which operate on the sleeves through connecting rods, one of which is shown at 68. The blades 138 are thereby moved forwards with the sheet as they descend so as to deposit the sheet in the correct position on the conveyer 150 or the stack of sheets formed theron. The camshaft 56 is rotated intermittently through a one revolution clutch in synchronism with the operation of a shearing mechanism (not shown) which severs the sheets from a web. A counting mechanism may be provided which counts the number of cycles of the stacking mechanism and after a predetermined number of cycles operates a clutch 220 whereby the conveyer 150 is moved a short distance so that sheets being stacked are separated into batches each containing the number of units determined by the setting of the counting mechanism.