Patent GB-386002-A (GB)
Title: Improvements in or relating to mechanism for use in printing machinery for selectiveprinting
IPC: B41L47/42
Filed: 1931-07-09
Abstract: 386,002. Printing-machines. ADDRESSOGRAPH-MULTIGRAPH, Ltd., (formerly ADDRESSOGRAPH, Ltd.), Grange Road, Willesden Green, and WOODHAMS, G. H., 101, Geary Road, Dollis Hill, both in London. July 9, 1931, No. 19818. [Class 100 (ii).] Addressing and like machines ; platen machines.-A printing-machine having intermittently-operated impression mechanism is provided with a plurality of impression surfaces each adapted to print a predetermined amount of matter from the type or the like in printing position, the impression surfaces being automatically brought in sequence into operative position, and each being selectively retained in operative position for a predetermined number of consecutive operations before being automatically removed and the next surface substituted therefor. As applied to an addressing machine, the impression mechanism comprises a rotatable four-sided platen block 2, each side of which carries a rubber &c. pad 3, the configuration of which determines the impression obtained from the printing device D. The block 2 is secured on two pins 4 journalled in members 20 projecting from a framework 21 which may be adjusted to vary the impression pressure by means of screws 5, which are operated by screws 23 meshing with a worm wheel 5<1> on the screws 5. One of the members 20 is removably mounted to enable the block 2 to be substituted. On one of the pins 4 is freely mounted, by means of two limbs, a bracket 7 carrying a pivotably mounted double-ended pawl 8. Ratchet and cam wheels 9, 10 respectively are rigidly secured to a stud 11 rotatably journalled in the upper end of the bracket 7. Rigidly mounted on the pin 4 between the two limbs of the bracket is a sprocket member 13 having teeth 14 equal in number to the impression surfaces of the block 2, one end of the pawl 8 being adapted to engage the teeth 14 and the other end being urged into engagement with the cam wheel 10 by a spring 15. The cam wheel 10 is provided with a number of deep and shallow recesses arranged in accordance with the particular number of operations desired with each impression surface and the sequence in which the impression surfaces are to be brought to operative position. The ratchet wheel 9 is provided with the same number of teeth as there are recesses in the cam wheel 10. A pawl 16 pivotally mounted on the framework 21, and spring-pressed into engagement with a throw-out lever 17, is positioned so that it lies in the path of the ratchet wheel 9. The bracket 7, together with its mechanism, is caused to rock about the pins 4 by means of a link 12 operated from some part of the machine, the operative stroke being from right to left. When the upper end of the pawl 8 is seated in a deep recess in the cam wheel 10 its lower end is adapted to engage the teeth 14 of the sprocket 13, so that upon actuation of the bracket 7 in a counterclockwise direction by the link 12, the sprocket 13 is rotated to move the impression block 2 to present a fresh impression surface in operative position. When the upper end of the pawl 8 engages a shallow recess in the cam wheel 10, the other end is maintained clear of the sprocket 13 and no rotation of the block 2 takes place. Actuation of the bracket 7 by the lever 12 in a clockwise direction brings the ratchet wheel 9 into engagement with the pawl 16 to rotate the stud 11, and consequently the cam wheel 10 to present the next recess to the pawl 8. With the pawl 16 in operative position the stud 11 is partially rotated upon each actuation of the lever 12, and the recesses in the cam wheel 10 are brought in succession to the pawl 8, so that according to the depth of recess presented to the pawl, the block 2 will or will not be rotated, and the particular arrangement of the recesses on the cam wheel 10 will determine the number of impressions to be taken from each impression surface 3. The arrangement can be varied by the substitution of a new cam wheel. Continuous printing from the same impression surface 3 is obtained by moving the pawl 16 out of operative position by the throw-out lever 17, and setting the cam wheel 10 by means of the stud 11 so that the pawl 8 engages a shallow recess and the other end is therefore clear of the sprocket 13 ; when it is desired to present each of the impression surfaces 3 in sequence once only to operative position, the pawl 8 is engaged in a deep recess in the wheel 10, thus allowing the - other end to engage the sprocket 13. The impression block 2 may be rotated by hand by providing a knurled head on one of the pins 4. The block 2 may have any number of sides, and it may be assoicated with yielding means which prevent any undesired movement of the block after the positioning of an impression surface 3.