GB569967A - Improvements in or relating to cut-off machines - Google Patents

Abstract

569,967. Cutting machines for paper &c. NEWTON, E. P. (Ehrsam & Sons Manufacturing Co., J. B.). Dea. 24,1943, No. 21665. [Class 31 (i)] A cutting machine which is especially applicable for cutting plaster board and the like as fed from a forming machine into lengths of adjustable size is constructed with a continuously rotated roller 16 fitted with four knives 17, 18, 19, 20 and a coacting roller 41 fitted with a single knife 64, the roller 41 being driven by means which can be disconnected selectively from its driving means and reconnected thereto in timed relation to cause the single blade to co-operate with any one of the four blades. Sheets can thus be cut which vary from a length equal to the circumference of the roller 16 to a length equal to this plus a multiple of a quarter of the length. The rollers 16, 41 can be arranged alternatively to cut completely or partially by varying the distance between the axis of the rollers, and means for varying the sequence of complete cuts and partial cuts or perforations is provided. The upper roller 41 is mounted in slides which are fitted with rollers 77 engaged by a cam on a shaft 79 which is movable to one of two positions corresponding to complete or partial severing. The work is fed over rollers 110, 111 on adjustable slides 112 which are lowered by eccentrics 120 to cause the work to contact with the lower roller before the upper cutter comes into action. The cutter roller 41 is driven by a one-revolution claw clutch 38, 52, of which the claw 38 is driven by an Oldham coupling from spur wheels 33, 34 driven from the roller 16 which is driven by chain gearing from a motor 27. The claw 52 is normally held from engagement by a trip dog 55 which is held in action by a spring-pressed lever 62. The lever 62 is acted upon by a trip element 76 on a chain 75 driven by bevel gears 66, 67 from the roller 16 to start the clutch, and after one revolution the clutch is thrown out against the action of a spring- pressed lever 49 by the action of the dog 55 on a cam surface 57 on the claw 52. Trip elements 76 may be used to cause the knife 64 to coact with either of the knives 17-20. Other trip elements 99 are provided to cause rotation of the cam shaft 79 through half a rotation and so control the extent of cutting. The elements 99 control the actuation of another one-revolution clutch 84, 105 acting similarly to the clutch 38, 52, and the elements 99 may be arranged to secure the desired sequence of complete or partial cuts. U.S.A. Specification 2,288,921 is referred to.