Patent GB-772648-A (GB)
Title: Cutting and creasing press
IPC: B26D3/08
Filed: 1955-05-18
Abstract: 772,648. Cutting-machines. S. & S. CORRUGATED PAPER MACHINERY CO., Inc. May 18, 1955 [June 15, 1954], No. 14378/55. Class 31 (1). [Also in Group XVI] A cutting and creasing press for sheet materials having a cylindrically-curved presser member 80 adapted by a rolling movement to press the sheet against a die 65 has means for gripping the leading edge of a sheet prior to its entry into the press and for feeding the sheet forwardly through the press, means for stopping the feed of the sheet during the pressing operation, means for accurately registering the leading edge of the sheet with the die for this operation, and means for opening the gripping means after the sheet has been fed from the press. Each sheet after it has been fed between the die 65 and presser member 80 is pressed by the rotation of this member about the centre of curvature of its curved surface 81. The member 80 is for this purpose supported by rollers 90, 91 on cams 92, 93 which are driven from a motor 41 and shaped so as to rock the member in opposite directions. Gaps 115, 116 in the cams permit the lowering of the corresponding ends of the member 80 to provide clearance of the sheets. The sheets are fed one at a time from the bottom of a stack by a feed slat 25, Fig. 1, operated by crank mechanism 28 from the motor 41, the sheet passing under a front gauge 22 and thence between feed rollers 50, 51 and a pair of conveyers 53, 54 to the press. The means for gripping and pulling the sheets through the press comprise a series of transverse bars 140 disposed on two endless chains 137, 138 which pass over intermittently-driven sprockets 136 and are guided in their travel by rollers 144 on the ends of the bars running in tracks 146. Each bar carries a plurality of toothed grippers each comprising a fixed lower jaw 200 and an upper jaw 201 in the form of a leaf-spring arranged to be moved upwardly to open position by a pivoted lever 206 actuated by a pivoted arm 271 through linkage 275, 278 from a cam 282 driven from the motor 41. The shaft 135 carrying the sprockets 136 is driven through a clutch 151 from a gear 150 meshing with a rack 160 on an arm 161 which is oscillated from a crank 166 on the shaft 95 of the cam 93. The clutch 151 effects drive of the chains only when the arm 161 moves downwardly and this action corresponds to the periods in the machine cycle when the presser member 80 is inoperative; a spring-pressed detent 182 co-operates with a disc 180 on the shaft 135 to prevent rotation of the latter when the clutch is ineffective. The timing of the machine cycle provides for the stopping of a bar 140 when, having passed around the curved end track 146a, it arrives at the entry end of the press at position 60a, its jaws 200, 201 being opened at this stage by the cam 282 and interdigitated with a series of pivoted stop fingers 250 which are then in their upper positions for correctly locating the leading edge of a sheet fed at that time from the conveyers 53, 54; any tendency of the bar 140 to be rocked about its axis when the jaws are opened is counteracted by causing the cam 282 to act through levers 301, 303 to give the bar a compensating rocking movement and maintain the jaws in correct position. The entry of the sheet between the jaws is controlled by guides on the stop fingers 250 and upper pivoted guides 331. With a sheet positioned in the jaws, a cam 320 driven from the motor 41 acts through a linkage to lower the stop fingers 250 and raise the upper guides 331, the cam 282 allows the jaws 200, 201 to grip the sheet, the crank 166 is effective to drive the chains 137, 138 through a distance sufficient to position the gripped sheet in the press (position 60b) and the presser member 80 performs an operating cycle on the sheet. Just prior to the stopping of the chains and the action of the presser member, a stop pin 341 at each side of the machine is urged upwardly by a motor-driven cam 350 for engaging the bar 140 and so properly locating the sheet in the press; at the same time, a pin 400 at each side is raised by a motor-driven cam 410 to lift both the bar 140 and leading edge of the sheet, and a bell-crank 415 is moved by the cam 410 into engagement with the trailing edge of the bar 140. After the pressing operation, the cams 350, 410 lower the bar 140 (and therefore strip the sheet from the die) and withdraw the stop pins 341 and bellcrank 415, and the crank 166 is then effective to move the chains sufficiently far to bring the bar with the gripped sheet to the delivery end of the machine (position 60c). Cams 482 at this point act similarly to the cams 282 to open the jaws 200, 201 so that the sheet can drop on to delivery belts 450 which move either longitudinally or laterally of the machine. The stop fingers 250 may be adjustable to vary the bite of the sheet in the jaws 200, 201. Specification 727,119 is referred to.