Patent GB-659919-A (GB)
Title: Improvements relating to method of making bottle closures
IPC: B21D51/48
Filed: 1949-03-17
Abstract: 659,919. Printing on and forming bottle caps. MID-WEST BOTTLE CAP CO. March 17, 1949, No. 7368. Convention date, March 22, 1948. [Class 100 (ii)] A method of making bottle caps from metallic foil comprises the steps of forming intaglio or depressed characters in a mouthspanning portion of the foil, covering the recess or recesses of the characters with a layer of ink and forming the caps from the foil while the ink is still wet. The formed caps may then be stacked in nested relation. As described, metal foil in the form of a blank strip 15 is fed from a roll 16 over tensioning rollers 18, 19, across female die members 21, 22 of a printing mechanism 23, through feed-rolls 24, 26, the roll 26 having an annular recess 38 so as not to touch the inked portion of the strip 15, thence to the cap-forming mechanism 27, the caps then falling on to a shoot 56, with side rims 57, leading to a conveyer belt 59 from whence they pass down a shoot 73 to be fed by rotating scraws 64, 65 up a belt 69, on which their edges rest, to a tube 74 in which they accumulate in a stack 75. The cap-shape, formed by the mechanism 27, of a rim 54 and pleated edge 55 is such that the inked top-portions 53 of the caps are held in the stack slightly apart and very slightly offset by the pleating, so that the ink is free to dry. The strip 15 may be of aluminium, or of laminated foil of foil and paper or foil and paper with an intermediate layer of a plastic adhesive wax or the like. The feed-rolls 24, 26 are intermittently rotated in timed relation with the printing mechanism 23 so that the portion of the strip 15 printed by a first die 31 is centred under a second die 32. Printing mechanism.-The printing mechanism 23 comprises a platen 28 supporting female die members 21, 22, formed of a relatively mouldable material such as heavy blotting paper, for co-operation with the male dies 31, 32 having raised characters such as stereotype plates and carried by an impression cylinder 29 which is mounted for rotation for inking the dies and for linear movement towards and away from the platen 28 for impressing the foil strip. Ink is supplied from a fountain 34 through rollers 35, 36 to the cylinder 29, doctor rollers 37 spreading the ink evenly over the die surfaces 31, 32, the foil being recessed and inked by the one operation. Cap forming mechanism.-The cap forming mechanism 27 comprises a stationary blanking die 42 co-operating with a male die 43 to sever the cap blank from the strip, the blank then being held against the edge of a female skirt forming die 44, the position shown in Fig. 4. Central retaining members 49, 48 grip the strip and hold it in alignment, the recessed characters in the part 53 lying in a recess 51 in the member 49, while die elements 46, 47 form the annular rim 54 on the cap, the cap then being formed with the annular skirt 55 by die elements 44, 45. The male dies 45, 47 and plate 48 pass through a deflector plate 50 and on return, a spring 52 pushes out the plate 48 to eject the finished cap, which passes on to shoot 56. Reference has been directed by the Comptroller to Specification, 647,611, [Group XVII].