Patent GB-928174-A (GB)
Title: Guillotine type paper cutting machine
IPC: B26D7/06
Filed: 1961-08-22
Abstract: 928,174. Guillotine cutting machines. MIEHLE-GOSS-DEXTER Inc. Aug. 22, 1961 [Aug.26, 1960], No. 30262/61. Class 31 (1). The knife bar 225, Fig. la, of a guillotine paper cutting machine is guided adjacent its ends between the front surfaces 11a of rear uprights 11 and the rear surfaces of gib members 14 secured to front uprights 12 by means of fastenings 16 which are adjustable to vary the spacing between the surfaces 11a, 12a at each end of the knife bar to compensate for wear of the knife bar. The knife bar is connected by means of pull-rods 220, 238, Fig. 1c, bell-crank levers 208, 234 and rods 204, 224 to a crank-pin 200 carried by a crank-arm 196 on a crank-shaft 180 which is driven from a shaft 55 through pinions 61, 183, 186, Fig. 4, gears 140, 63, 192 and a spring-urged friction clutch 154, 157 disposed between the gear 140 and a sleeve 143 keyed to the crank-shaft 180. The shaft 55 is driven from a motor-driven flywheel 58, Fig. 2, by means of a clutch 80 and the shaft has a brake 66 mounted thereon. The clutch is operable by a cam 91A and the brake by a pressure-plate 73, the plate 73 and cam 91A being integrally mounted on a collar 93 splined on the shaft 55. The collar 93 is straddled by a fork-like element 94 connected to the piston-rod 112 of a piston 106 movable in an hydraulic cylinder 103. The piston-rod is surrounded by a spring 123 which biases the piston to effect brake engagement and clutch disengagement. When pressure-fluid is admitted to conduit 109 it overcomes the pressure of spring 123 so as to effect clutch engagement and brake disengagement. A safety latch 249, Fig. 9, rockable about a fixed pin 252 has an arm 249a, the surface 249b of which is engageable by a roller 238 carried by the crank arm 196 so as to effect electrical cut-off and thus prevent a cutting cycle from starting. The latch has a further arm 255 connected with the plunger link 262 of a solenoid 273 which when energized rocks the latch clockwise about the pin 252 to withdraw the latch from the roller 238<SP>1</SP> and cause an abutment 293 to engage and reciprocate a plunger 296 to close a switch 300a to permit the cutting cycle to take place. Counter-clockwise rotation of the latch is prevented by a fixed stop 258 engaging the arm 255. The crank arm 196 carries a spring-influenced shading member 280 which as the crank arm revolves clockwise engages the surface 249b and remains there until such time as the roller 238<SP>1</SP> engages the latch. The clamp 300, Fig. 12, is connected by links 352 and bell-crank levers 336 to a rod 348 in turn connected by a bell-crank lever 336 and a pullrod 324 to one end of a pivotally-mounted lever 308 the other end of which is connected to the piston-rod 386, Fig. 13, of a piston movable in a rockably-mounted hydraulic cylinder 380. To prevent unintended downward movement of the clamp, a bottom dashpot portion 369 of a vent valve 365 is forced upwardly. The cylinder 380 has a pre-fill valve 388 which is normally biased to the closed position and openable by suction within the cylinder. The hydraulic system includes multi-way valves 392, 396 for operating the clamp and knife, respectively. The back gauge 600, Fig. 18, has a guide 612 in which are disposed nuts 624, 628, Fig. 20, which are forced apart by a spring 644 to engage the threads of a screw 616, the nut 624 being relatively immovable within the guide while the nut 628 may move longitudinally but is restrained against rotation. The screw is driven from a countershaft 658, Fig. 21, which is driven optionally at high or low speed by means of an electric motor 662 having high and low speed shafts 668, 665, respectively. The drive from the motor shafts to the shaft 658 includes belts and pulleys and electromagnetic clutches, and the drive from the motor shaft 665 also includes a friction clutch. The clamp has secured to the bottom surface thereof a false plate 804, Fig. 24, having an upwardly-turned flange 824 which touches the rear tips of the clamp fingers 828 so as to prevent any portion of the clamp plate from moving or being pushed under the knife.