GB1162667A - Improvements in or relating to Ink Feeding Arrangements for Printing Machines - Google Patents

Abstract

1,162,667. Stencilling apparatus; inking. DARGOLS, and M. G. de SOUZA DIAS. 7 Oct., 1966 [7 Oct., 1965], No. 44964/66. Heading B6C. Ink feeding apparatus for a printing machine having a relatively movable impression member and a spreader element, e.g. a silk-screen and a squeegee, comprises an ink storage cylinder and a piston movable under the action of compressed air to force ink out of the cylinder through duct means to the spreader element. General arrangement (Fig. 1).-A frame 7 is slidable in the directions F on guide-bars 8 under the action of a pneumatic jack (9), Fig. 2 (not shown); a silk-screen 6 is tensioned on the frame 7 so that the screen is movable relative to a squeegee 10 which is pivotally mounted on spindle 10a, and is raised or lowered under the action of a second pneumatic jack (11). The article 5 to be printed is generally cylindrical and is supported on rollers 4 mounted on a carriage 1 which is slidable transversely across the screen 6. Inking apparatus (Fig. 3).-The inking apparatus comprises a cylinder 21 having a piston 24 separating chamber 21a which contains ink, from chamber 21b; the chamber 21a is connected to supply ducts 22 which extend to positions near the lower edge of the squeegee 10, Fig. 1, while chamber 21b connects with a line 25 for compressed air. The piston-rod 23 can ies a pointer 27 co-operating with a scale 26 to indicate the amount of ink remaining in chamber 21a. When the chamber is empty, cylinder 21 is inverted, and channelled block (29), Figs. 4 and 5 (not shown), is removed so that the cylinder can be refilled with ink. Diluent can be added to chamber 21a at any time from reservoir 30 through pipe 31, or from cup 28 through bore 23a in piston-rod 23 when a further rod 29 is removed from the bore. This diluent can also act as a solvent for cleaning the cylinder and supply ducts. Operation.-Pneumatic control circuits, Fig. 2 (not shown), operate when an article 5 is placed on carriage 1 and actuates valve 15 to cause movement of the screen 6 across the article; simultaneously squeegee 10 is lowered and compressed air is admitted to chamber 21b to cause ink to be discharged through ducts 22. At the end of the printing stroke, the squeegee is raised. When pointer 27 reaches zero on scale 26, the main air line is automatically disconnected.