GB838600A - Plate locating mechanism for stereotype plate finishing machine - Google Patents

Abstract

838,600. Printing surfaces. MIEHLEGOSS-DEXTER Inc. April 9, 1958 [ApriI 15, 1957], No. 11301/58. Class 100(2) A method of making partial size stereotype printing plates consists in casting a full sized semi-cylindrical stereotype plate with the impression for at least one partial size plate at the periphery thereof, milling in the underside of such plate and adjacent at least one straight edge thereof a row of tension lock-up pockets, sawing the plate into sections thereby to produce individual partial size plates and milling a second row of tension locked-up pockets adjacent the newly sawn edge of the or each individual plate bearing the impression while locating the plate by means of the tension lock-up pockets previously milled on the full-sized plate. The machine for milling the tension lock-up pockets in the semi-cylindrical plate may be of the type described in Specification 838,598 and includes milling cutters 23 and a saddle 24 on which an inverted stereotype plate 25 may be held by clamps 29 (Fig. 5). The machine, however, additionally includes engaging members 43, 44 for tabloid size plates. After the full sized plate has been milled it is sawn in two. The members 43, 44 are then rotated to the position shown in Fig. 6 to engage the pockets adjacent the milled edge of the tabloid plate 41 whilst pockets are milled in the sawn edge by the cutters 23. Two hooks 43 are provided and one biasing finger 44. The hooks 43 are pivotally mounted on rods 49 supported by bodies 51 carried in recesses 53 formed in the saddle 24. The hooks are held in each of the two positions by springs 68 which co-operate with nose portions 66 on the hooks. The biasing finger 44 is rotatably mounted on a shaft 70 journalled in the saddle. An operating handle is provided for turning the shaft 70. A torsion spring 71 has one end connected to the shaft 70 and the other end 74 bears on the finger 44 to urge it, when the shaft is rotated clockwise, as viewed in Fig. 6, against the edge of the tabloid plate 41. In a second embodiment the hooks 43 are replaced by hooks 87 (Fig. 13) which slide vertically in the saddle 85, are normally urged by springs 89 to a position beneath the surface of the saddle, but may be raised to engage a tabloid plate by cams 93 on shafts 95 which may be rotated by means of key members inserted through suitable openings in the saddle. In a further embodiment, Fig. 18, two tabloid plates may be held on the saddle and milled simultaneously. Two sets of rotatable plate engaging hooks 131 rotatable on shafts 126, 127 are provided which are held in position, similarly to hooks 43. by a spring 133. A plate retaining member in the form of a plunger 134 is provided which is operated by a handle 136. The plunger 134 is held in non-operative position by means of spring-loaded detents. Specifications 628,134, 688,566 and 838,597 also are referred to.