Patent GB-781118-A (GB)
Title: Proofing press
IPC: B41F27/00
Filed: 1955-05-13
Abstract: 781,118. Rotary proof printing and transfer presses. MASCHINENFABRIK GOEBEL GFS. May 13,1955 [May 15, 1954; Nov. 17, 1954], No. 13964/55. Class 100(2) In a rotary proof-printing press, which is adapted for transfer of carbon tissues, the forme cylinder 4 is in operative engagement with driving means but the impression cylinder 2 is not driven until cooperating means on the two cylinders are engaged at a determined position, whereupon the cylinder 2 is driven for a short period by these means, and continued rotation of this cylinder is effected through gearing or by peripheral contact with the cylinder 4. The press shown is for intaglio printing, the cylinder 4 being mounted in adjustable bearings which allow cylinders of larger or smaller diameter to be accommodated. This cylinder dips into an ink container 11 which is supported by means 12, adjustable by a lever 13, and doctor blade 6 for removing surplus ink is carried by a pivoted lever 7 provided with an extension 10 on which is an adjustable weight 9. The shaft 3 of the impression cylinder 2 is mounted in fixed bearings, and has freely rotatable thereon a gear which meshes with a motor-driven gear 27 and a wide gear 29 (not shown) secured on the shaft 30 of the forme cylinder 4, so that the latter is always rotating. A disc 32 secured to the gear 29 (not shown) has a recess 33 therein, and a disc 34, secured on the shaft 3 and supporting a toothed segment 31, has a guide frame 35 thereon in which is a slide 36 carrying a forward roller 38 adapted to engage the recess 33 in the driven disc 32 to form the initial driving connection between the two cylinders. After this initial rotation, the gear segment 31 meshes with the gear 29 (not shown) and subsequent rotation of the cylinder 2 is by peripheral contact between the cylinders 2, 4, the cylinder 2 being stopped at or before the completion of one revolution. The slide 36 is urged forwardly by a spring, and is held in the retracted position by a transversely slidable pin 42 engaging a roller 40 in the slide. The slide is automatically retracted before the full rotation of the cylinder 2 by the action of cams 43, 44, 45, and the roller 40 brought into engagement with the pin 42. The pin 42 is retracted by a hand lever to allow the slide 36 to move forward and start the rotation of the cylinder 2. When the roller 38 engages the recess 33 the speed of the press is reduced momentarily either by the application of a brake or other means which may be controlled by the hand lever for moving the release pin 42, and the speed may then be increased by the actuation of a contact device by the rotation of the cylinder 2. The cylinder 2 is provided with sheet-register stops 18, adjustable by micrometer screws 21, and a lever 20, and with sheet-grippers 15. The operative surface 14 has a bigger radius than the remainder so that there is no contact with the cylinder 4 in the inoperative position shown in Fig. 1. The proof sheet is disposed initially on a displaceable feed table 22 against adjustable side stops 23. Instead of printing the second. colour directly on to the proof sheet, a transparent web is drawn from a roll 47,  housed in the cylinder 2, around the proof sheet and gripped by the grippers 15, or wound on to another roll and printed with the second colour. It can then be seen whether this pattern is in register with the first. Transferring carbon tissues:-The proof press can be utilized to transfer a carbon tissue from the impression cylinder 2 to the forme cylinder 4, in which case the container 11 has water therein. The carbon tissue comprises a sheet coated with gelatine joined to a leading reinforcing strip by an adhesive which allows the strip to be stripped from the tissue when the tissue has been wrapped around the moistened cylinder 4, so that the gelatine layer adheres thereto. The leading strip has registration holes therein which fit over pins in the recessed portion of the cylinder 2, and the strip is also held by the grippers 15. The tissue is thus accurately registered on the cylinder 2, and is applied accurately to the cylinder 4 in view of the co-operating driving means . described above.