Patent GB-1189204-A (GB)
Title: Device for Cutting Sheet Material
IPC: B26F1/00
Filed: 1967-07-11
Abstract: 1,189,204. Cutting apparatus. GERBER SCIENTIFIC INSTRUMENT CO. 11 July 1967 [21 Sept., 1966], No. 31767/67. Heading B4B. A device for cutting sheet material comprises a cutter head 20, Fig. 1, having a reciprocating cutting tool, rotatable about its longitudinal axis to enable the cutting edge to be kept tangential to the line of cutting, the cutter head being movable along a carriage 72 in direction Y and the carriage being movable in direction X so that the cutter head has a two-dimensional movement with respect to material 22 supported on a table 26. The material 22 may be held to the surface 28 of the table by vacuum. The surface 28 is preferably made of rubber. A computer 34 controls the movement of the cutter head along the line to be cut, the rotation of the cutting tool and the lifting of the cutter head between a cutting and a non-cutting condition. The computer has an input device in the form of a magnetic tape transport mechanism 76 which handles a tape having recorded thereon coded information utilized by the computer to drive two-dimensional command signals. A motor 78, Fig. 2, is operable to shift the cutter head between its cutting and non- cutting condition, a motor 40 is operable to rotate the tool about its longitudinal axis, while motors 46 and 48 are operable to drive the carriage 72 in the X direction and the part 60 of the carriage to which the cutter head is attached in the Y direction. The cutter head comprises a frame 62, Figs. 5 and 6, fixed to the carriage part 60 and a plate 72 carrying the cutting tool 90 and its operating mechanism. The plate is movable vertically along guide rails 66, 68 with respect to the frame 62. The plate 72 is operable by the motor 78 through a cam 86 co-operating with a roller 88 carried by the plate. The plate 72 is lockable in its raised inoperative position. The cutting tool 90, Figs. 5, 6 and 11, is supported for reciprocation by two spaced bushings 102 retained in an annular guide member 104 fixed to a bracket 106 attached to the plate 72. The guide member 104 is externally threaded to receive a presser member 110 having a face 112 adapted to engage the sheet material to be cut. The member 110, which is adjustable on the guide member 104 to vary the depth of cutting, is held in a selected angular position by detent means comprising a spring-biased ball plunger 118 fixed to the member 110 engageable in one of a number of grooves 116 on the member 104. The cutting tool 90 is reciprocated by a motor 120, fixed to the plate 72, the shaft 126 of the motor being extended by an eccentric pin 128 oscillating a connecting rod 172 connected at its other end with a part 174 attached to a chuck for the cutting tool. The chuck is rotatable with respect to the part 134 by means including a gear 172 meshing with a gear 174 fixed to the shaft 176 of the motor 40. The motor 40 has associated therewith a switch (42), Fig. 10 (not shown), for providing a signal representative of the tool angle. The cutting tool may produce either a continuous cut or perforate the sheet material by a series of spaced cuts or perforations.