Patent GB-191205004-A (GB)
Title: Improvements in Printing Machines.
Inventor: LAKE WILLIAM EDWARD
IPC: B41F3/30
Filed: 1912-02-28
Granted: 1912-12-19
Abstract: 5004. Lake, W. E., [Huebner-Bleistein Patents Co.]. Feb. 28. Cylinder offset machines; printing-surfaces.- Relates to cylinder offset printing-machines for producing designs from a primary printing- surface on to a secondary printing - surface, proof-sheet, or the like, particularly applicable for building up a design on a secondary surface by making thereon a series of impressions. The design may be made on to a photographic surface and fixed by exposure to light beneath a pivoted light-chamber. The machine comprises a frame A supporting primary and secondary printing-plate beds B, C. From these beds depend screws D, d<8> passing through screwed sleeves d<1>, d<9>, which are rotated by bevel-gear d<3> from shafts d<4>. These shafts are turned to adjust the beds to the correct printing position by hand-wheels on two transverse shafts. These shafts are operated rapidly to trip the beds by gear sectors on hand-levers carried by eccentrically-mounted shafts e<1>, e<8>. During the initial adjustment, these sectors are out of gear, but when this is effected, they are thrown into gear by operating the eccentric bearings of the shafts e<1>, e<8>. The beds B, C are furnished with plate clamps I for attaching flexible plates, which can be set slightly oblique to the edges of the beds by thumb-screws i<5> which bear on eccentrics i<4> on the transverse shafts i<3>. The beds may be provided with an adjustable plate-holder K, Fig. 19, by means of which a plate may be secured in any desired position. The holder comprises a baseplate K<1> attached by depending pins to the bed C, and a centrally - pivoted plate K<2> having parallel upstanding flanges k<2> accommodating a sliding bed K<3>. The plate K<2> is roughly set by hand and can then be finely adjusted and clamped by a worm or a screw k<4>, turning in a block k<8> pivoted in a block k<9> moving in a guide k<10>. The block k<9> is clamped in the guide by a screw k<11>. The screw k<4> is held into or out of engagement with a sector k<6>, k<7> on the end of the plate K<2> by a slide k<12> which works over a screw k<13>. The plate K<3> carries a screw l<1> mounted in pivoted bearings, which can be rocked into or out of engagement with a rack l on the plate K<2>. The screw is rocked out of engagement with the rack to permit the plate to be roughly adjusted by hand and then into engagement for the final accurate adjustment. Centrally pivoted on the plate K<3> is a plate K<4>, which can be roughly set and then adjusted by a screw l<6>. The bed C is provided with suction parts for holding a sheet of paper, and with gauges integral with the plate-straining grippers, against which the sheets may be positioned when the machine is used for printing direct on to paper. Co-operating with the beds are two offset cylinders F, M, the former being of full length for printing a complete design, the latter shorter and adjustable axially for repeating a smaller design. These cylinders are mounted in carriages G provided with rollers N<5> engaging the underside of rails g<6> on the frame. The cylinders carry wheels N, N<1> at each end consisting of two bevelled surfaces g' with oblique teeth g<3> between, which engage corresponding racks g<2> on the frame. The cylinders are driven by gearing n<2>, n<3> from electric motors mounted on the carriages G. The wheels N, N' are loose on the offset cylinder M, but are connected to flanges n<4> thereon by spring dogs n<7> which can be held out of engagement by screws n<8>. The flanges n<4> are connected by tubes n<5> which pass through the cylinder M. The cylinder can be adjusted relatively to the wheels by disengaging the dogs n<7> and turning the cylinder by means of a handle n<9>, which works against a scale n<10>. The cylinder is adjusted axially by turning the screwed shaft P by means of a handle p'. The cylinders F, M are furnished with blanket rods f<1>, m'. In order to permit the cylinders F, M to be turned while their carriages are stationary, short sections R, R<1> at each end of the racks g<2> can be depressed out of engagement with the cylinder. gear wheels. These sections are formed on slides r, which can be raised into position against springs r<2> by diskes r<3>, r<6> on shafts r<4>, r<7>. To enable the primary and secondary surfaces to be placed in the same relative positions on the beds B, C, a registering-device is provided comprising a sheet of glass in a frame which is grooved to fit over the tracks g<2> on the frame and provided with pins adapted to fit into recesses in the frame. The glass is ruled with centrally-intersecting lines, and provided with circular apertures through which the plates are accessible. When photographic impressions are being produced, the secondary surface, after printing, is exposed beneath a light - chamber S which is pivoted on one side of the frame, so that it can be turned out of the way. Within the chamber is a series of lamps s, and across the face thereof are four screens on rollers s<5> so that any desired part of the plate can he exposed.