GB426804A - Improvements in or relating to platen printing presses - Google Patents

Abstract

426,804. Printing-machines. THOMPSON & SON, Ltd., T. C., and THOMPSON, F. S., 26, Buxton Street, London Road, Manchester. Oct. 13, 1933, No. 28308. [Classes 100 (i) and 100 (ii)] A platen printing-machine of the kind in which a gripper arm 10 mounted on a pivoted platen 7 is oscillated about an axis perpendicular to the plates and takes a sheet from a pile 27 and transfers it to the platen during the upward movement thereof by moving across the platen from the position shown in dotted lines, Fig. 2, to the full line position, is constructed so that the gripper arm 10 releases the sheet before the printing operation, and a registering device registers the sheet on the platen clear of the gripper arm before the impression. The gripper arm 10 and the registering means return to their initial positions during or after the return of the platen to its open position, and the printed sheet is removed by a second gripper device 31 which reciprocates laterally of the machine. The arm 10 is oscillated through 90‹ at each operation of the platen by means of a cam 11, Fig. 3, on the main drive shaft x, which oscillates a lever 16 and reciprocates in guides 19 a rack 18 engaging a pinion 20 on a shaft 21 connected by a universal joint 22 to a shaft 23 geared by bevel wheels 24, 25 to the shaft of the arm 10. To lock the arm 10 in its positions of rest radial members 63, 64 associated with the cam 11 engage at intervals notches in a disc 60 on the shaft 21. The grippers on the arm 10 are of known kind and are operated by a link 32, lever 34, and a cam 37 on the shaft x. The grippers 31 are carried by a slide 45, Fig. 2, which is reciprocated on guide bars 46 by means of a link 49, and an oscillating lever 47 formed with a sinuous slot 52 which is engaged by a crank pin 50 on a disc 51 fitted to a shaft 53 driven by worm gearing from the shaft x. The grippers 31 are opened and closed by strikers 54, 55 operated from a lever 58 which is operated by a cam 59 on the reverse side of the crank disc 51. According to the Provisional Specification an oscillating segmental gear may replace the sliding rack 18.