Patent GB-980438-A (GB)
Title: Sheet printing machine
IPC: G05D1/06
Filed: 1961-12-05
Abstract: 980,438. Printing-machines. SOC. ALSACIENNE DE CONSTRUCTIONS MECA. NIQUES. Dec. 5, 1961 [Dec. 7, 1960], No. 43465/61. Heading B6C. An offset multi-colour cylinder printing machine comprises an endless conveyer for supporting a length of sheet material 10, such as a textile fabric, to be printed on, means for intermittently advancing the conveyer in a longitudinal direction, an offset roller 6 in each of a series of printing assemblies 21, 22, 23, 24 supported with its axis parallel to said longitudinal direction and adapted to receive an inked pattern from a plate supported on a bedplate 5, and means operable in timed relationship with the advancing means for moving the roller 6 transversely across the surface of the material 10 in rolling engagement therewith during a stationary period of said conveyer to transfer the pattern to said material.The invention is also applicable to the printing of paper, plastics or rigid materials such as sheet metal. Grippers.-The conveyer is moved intermittently by four clamping trucks 26, 27, 28, 29 which engage the sides of the upper run of the conveyer, truck 26 being connected to the piston-rod of a double-acting fluid pressure actuator V1 and the other trucks being interconnected by rods 37, 38 and 39. Each clamping truck comprises a generally rectangular body 46 supported on rollers 47 which engage rails 31 and the flat upper surface 46 of each truck engages the underside of the upper run of the belt and co-operates with an upper member 48 supported by rods slidable in a pair of vertically disposed hydraulic cylinders V2. The members 48 are lowered to grip the edges of the conveyer and the material 10 and then pressure oil is applied to actuator V1 to displace the conveyer forwardly until stop 41 abuts member 43. The members 48 are then raised and the trucks returned until stop 41 abuts member 42. A stationary clamp 56 is provided which is released when the clamping trucks are in a clamped position and vice versa. Inking.-The inking assembly, Fig. 8, of each printing assembly comprises a fountain 71, a fountain roller 72, a swinging messenger roller 73, further rolls 74, 75, 76, 77 and three axially reciprocating rolls 78, 79 and 80. The rolls are rotated from a motor M via a shaft having two threaded sections 83, 84 of opposite pitch. Each roll 78, 79, 80 is reciprocated by a mechanism including a grooved ring 96 engaged by a pivoted fork which engages at its other end a helical groove in the periphery of a cam 99. The rolls 76 and 77 co-operate with three inking rolls 87, 88 and 89 which are mounted in a horizontally reciprocable carriage 92 and which ink the pattern plate. The rolls 87, 88, and 89 are supported in the carriage 92 between pairs of arms 111-112, 115-116, and 117-118 pivoted on pivots 113-114, 121-122, and 123-124, respectively, so as to be vertically displaceable a limited amount. The carriage 92 is mounted on rollers 93 which engage rails 94, 95 and is driven by a motor M1 which rotates lead-screws 135, 136. Operation.-The offset roll 6 in each printing assembly is supported on a carriage 146, Fig. 11, which is reciprocated by an electric motor M2 mounted thereon. The roll 6 is positively rotated by a system of gearing which engages a pair of racks which is reciprocated longitudinally relative to the rails on which the carriage 146 runs by hydraulic actuators V5. The control of the various hydraulic and electric components is derived from a single continuously rotating cam-shaft, Fig. 15 (not shown). Tripping.-Each roll 6 is journalled in pivoted lever arms connected by a member 171 and the piston-rod 175 of an hydraulic actuator V4 is connected to the member 171 so that on the application of fluid pressure the roll may be raised or lowered. The printing assemblies may print black and in three colours in addition and the invention is stated 'to be applicable to wet offset printing or intaglio offset printing.