GB746100A - Apparatus for decorating or printing on non-planar surfaces of articles - Google Patents

Abstract

746,100. Stencilling apparatus. VALIELA, J. Jan. 21, 1954, No. 1871/54. Class 100 (2). In a machine for printing an article having non-planar surfaces by applying the design by a silk-screen stencil to an elastic offset diaphragm which is then pressed on to the article by fluid pressure, the diaphragm-carrying section of the machine table is hinged to the recessed article-supporting section, e.g. as described in Specification 646,394, but the stencil frame is slidable along the table to and from a position over the diaphragm. Two stencil frames sliding in directions at right angles to each other may be used with a single diaphragm for two-colour printing. In Fig. 1 the stencil frame 13 is fixed by bolts and wing-nuts to a metal or other frame 14 slidable by handles 16 along guide grooves 20 in the top of the table 11, from the inoperative position shown to its printing position in which an adjustable bolt 22 contacts a fixed stop 23; a squeegee with two handles 18 is provided. The rubber &c. offset diaphragm 25 is stretched over a circular foraminate plate 26 by a clamping ring 33, the plate forming one surface of a hollow metal block 27 hinged at 40 to the table 11 so that the diaphragm 25 may be turned over the article 60 to be printed, and then forced into contact therewith by compressed air admitted through a conduit 31 to the interior of the block 27, the latter being isolated by a cross-tube 38 from a light floating tube 36 open to atmosphere and leading to a small reinforced opening 35 in the diaphragm 25, whereby air trapped between the diaphragm and the article 60 may escape, and whereby after printing air may re-enter to allow the diaphragm to retract. The ceramic article 60, such as a plate, is supported by an exchangeable frame 51 having an inclined part 52 and a cylindrical part 53 containing an adjustable platform 55; to centre the plate three sliding radial fingers spaced at 120 degrees around the outer part of the frame 51 are simultaneously moved inwards against the rim of the plate by a handle 70 which rotates a spring- biased ring 63 having cam channels engaged by pins on the radial fingers; for small plates an inner ring 71 may be inserted to provide extended support slots for the radial fingers. The lock to hold the diaphragm block 27 in position during printing, consisting of a roller 76 and handle 77 at the top of a rotatable post 75, may be coupled to a control valve 79 which connects a conduit 82, leading to the conduit 31, either to a source of compressed air at 81 or to atmosphere. Fig. 4 shows an ejector for lifting the printed plate 60 to facilitate removal by hand: a rod 65 is projected through an opening in the inclined part 52 of the frame 51 by a spring- loaded plunger 91 carrying a sliding block 87 to which the rod 86 is pivoted.