Patent GB-379069-A (GB)
Title: Improvements in or relating to cutting and collecting mechanism for use in printing machines
IPC: B41F13/54
Filed: 1931-07-30
Abstract: 379,069. Cutting and associating apparatus for printing-machines. HOE & CO., Ltd., R., 109, Borough Road, London. -(Hoe & Co., Inc., R.; 138th Street, New York, U.S.A.) July 30, 1931, No. 21828. [Class 100 (i).] In a cutting and collecting mechanism for use in rotary web printing-machines, the cutting- cylinder is provided with means for automatically varying its circumferential length when the thickness of the product varies. The cutting-cylinder 11, Fig. 1, is provided with a cutting-knife 12 with cheek-blocks 13, and the collecting-cylinder 14 is provided with a cooperating abutment 15. Known pin-operating mechanism which engages a web or group of webs 17 to hold it on the cutting-cylinder includes pins 16, a pin holder 18, an operating arm 19, a shaft 21, and a cam roller 22 which engages a stationary cam fixed to the frame of the machine. Similar pins 23 and operating- mechanism are used in the collecting-cylinder 14. When a paper having two sections is to be delivered, the pins 16 engage the end of the web, and as the cylinder 11 rotates, the web is carried around the cylinder and cut when the knife 12 and the abutment 15 engage. As the cylinders rotate the pins 16 are withdrawn and the pins 23 engage both the cut end of the web and the cut section on the cylinder 11. Both sections are then carried forward by the cylinder 14 and at the next revolution of the cylinder 11 the second section of the web is cut, after which the two sections are folded and passed on to a delivery-mechanism. The diameter of the cutting-cylinder is such that it will cut the maximum thickness of the product ; means is provided for increasing the effective circumferential length of the cylinder when a thinner product is cut and comprises a shaft 24 rotatably supported in bearings in the end of the cylinder 11, an eccentric member 25 keyed to the shaft and provided with a face 26 adapted to support the webs 17, and thrust rods 27, which engage the eccentric 25, arranged to slide in recesses 28. The thrust rods 27, acted upon by springs 29, tend to thrust the eccentric 25 outwardly, the outward motion being governed by a block 31 engaged by a projection 32<1> framed on a casting 32 secured to the shaft 24. The block 31 is adjustable by means of a screw supported in lugs 34 secured to the end wall of the cylinder 11. When the webs are taken by the pins 16, rotation of the cylinder 11 will bring the face of the eccentric into engagement with the webs, and if a thick product is being handled the eccentric will be forced into the recess of the cylinder. If a thinner product is being handled the eccentric will protrude beyond the surface of the cylinder 11 to an extent that is governed by the thickness of the product, and is held in that position by the tension of the web on the one side and the pressure of the springs 29 on the other. The thinner product will, by reason of the increase in the circumferential length of the cylinder 11, be cut into sections of longer length than with the usual form of cutting-cylinder having a proper diameter for cutting heavy products. In the modification shown in Fig. 4, a large portion of the surface of the cutting-cylinder is cut away, forming a recess 42 in which are mounted interlocking segments 43, 44, supported on rotatably mounted shafts 45, 46 respectively. Springs 48 in recesses 49 in the cutting-cylinder act on the inner surfaces of the interlocking segments 43, 44 to thrust them outwards, and screws 47 engaging the segments and threaded in the cylinder adjust the maximum outward movement of the segment. In another modification a single movable segment is used which is pivoted at one side and is thrust outwardly by spring-pressed thrust members. Adjusting- screws provided in lugs at each end of the cylinder engage lugs on the thrust members to limit the outward movement of the segment. In a further modification the cutting-cylinder is recessed to accommodate a spring-pressed block, which block is retained by adjusting- screws.