Patent GB-1031931-A (GB)
Title: Register microscope for precision measured mounting work of printing surface or its components
IPC: B41B1/00
Filed: 1963-02-15
Abstract: 1,031,931. Printing apparatus. R. T. RAIVIO. Feb. 15, 1963 [Feb. 16, 1962], No. 6305/63. Heading B6C. [Also in Division G2] A device for registering a printing surface with a model surface comprises supports 1, 33, Fig. 3, for the two surfaces and an enlarging optical system 80, 81, 84, 90, for viewing superimposed images of corresponding regions of the two surfaces, the supports and optical system being so movable relative to one another in the printing direction that the two surfaces may be conjointly explored in the printing direction. The cylinder support 33 having two points So, So<SP>1</SP>, Fig. 10 (not shown) on its periphery appears, through prisms 80, 81, to be in the position of a circle, centre Q, with points S and S<SP>1</SP>, point S being initially coincident with the. corresponding point U on the printing surface on bed support 1. Assuming a pure rolling motion of the cylinder 33 on bed 1 to the point Q<SP>1</SP>, point S<SP>1</SP> arrives at S<SP>11</SP> which in general is not coincident with the corresponding point U' because of a difference of scales. This is corrected by superimposing an additional rotation on the cylinder 33 about the point Q<SP>1</SP>, i.e. a glide movement. This is done by the shaft 26 of cylinder 33, which rotates by gearwheels 24, 25, Fig. 1 (not shown), thereon engaging fixed racks 22, 23, also having a further gear 34 with a different number of teeth from gear 25, to engage and slide a rack 35 longitudinally as the shaft 26 rotates. This movement is transmitted by a lever 36, whose fulcrum 37 can be adjusted to vary the lever ratio, to a further rack 39 rotating a gear 40 fixed to a shaft 40a carrying the cylinder 33. In modifications the movement is transmitted to the bed 1 which is then supported in bearings, and cylinder 33 is fixed with respect to shaft 26, or the glide movement is obtained by an eccentric on shaft 26 and a lever operating thereagainst fitted to an end piece 21, the movement being transmitted by a lever to the optical system. For cylindrical printing surfaces, Figs. 8a, 8b, 8c (not shown), the cylinder 46 carrying the printing surface rotates about an axis parallel to the model carrier cylinder 33 and gears 47, 48, and 49, 50, intermesh, the sum of both sets of teeth being the same but the gear ratios being different so that gear 50 which is free to rotate on shaft 48a of gear 48 rotates at a different speed from gear 48 fixed to shaft 48a and a connecting bar 51 is skewed. This motion is transmitted by an adjustable fulcrum 52 and pin 53 to provide the glide motion of cylinder 33. For a flat bed construction gear wheels 47, 49, are replaced by a rack 54 corresponding to racks 22, 39 but fixed to the frame of the device. A flat bed 1 and printing cylinder 46 may be combined in one device, Figs. 9a, 9b (not shown). The basic picture fixed on the sheet 61 forming the outer surface of cylinder 33 may be skewed in both directions by an adjusting screw 66, Fig. 1 (not shown), adjusted parallel to the cylinder axis by an adjustment 60 and longitudinally by a screw 45. The carriage supporting cylinder 33 comprises end pieces 20, 21 and guide bars 17, 18, the frame 69 carrying the optical system being slidable by wheels 72-75 on the bars 17, 18, which are so arranged and of different strengths that when under stress by a chin engaging a chin rest 93, for moving the optical system, the superimposed images are not distributed.