GB372950A - Improvements in or relating to molds for molding rubber stamps or dies - Google Patents

Abstract

372,950. Printing surfaces. EVANS, R., 63, Eastwood Avenue, Highland Park, Illinois, U.S.A. May 15, 1931, No. 14459. [Classes 100 (ii) and 100 (iii).] A mould for moulding rubber printing stamps or dies comprises a number of intaglio type locked up in a frame and provided with grooves or channels for the escape of air from the intaglio recesses during the moulding operation. As shown in Fig. 8, intaglio types 17, type spaces 18 and line spacers 19 are locked up in a frame 10 by means of screws 13 and clamping plates 20, 22 and the types 17 and spaces 18 are provided with communicating grooves 23, 24 through which air can escape when a sheet of rubber is pressed on to the mould. The air can pass freely out of the mould through passages 26 between packing strips 25 at the ends of the rows of type. To facilitate the alignment of the lower faces of the types in one plane, the types may be provided with shoulders 28, Fig. 4, on which the line spacers 19 may rest and be pressed down, or the line spacers may be provided with heads 35, Fig. 7, on one or both sides to press upon the upper faces of one or adjacent lines of type. These heads may be tapered as shown so that the moulded type are formed with inclined sides. The alignment also may be effected by a rod engaging notches 29, Fig. 5, in the types. The depth of the moulded type bodies may be varied by using spacers 19, Fig. 3, extending more or less above the level of the types 17 or the types may be formed with side flanges 30, Fig. 5, on one or both sides for this purpose. Thin knife-like plates 27, Fig. 3, may be arranged in the mould to facilitate cutting up the moulded sheet of rubber. The lower ends of the types may be provided with positive type characters 31, Fig. 5, to facilitate composing the mould.