Patent GB-518393-A (GB)
Title: Improvements in and relating to methods of and apparatus for applying centre spots tocrown caps
IPC: B21D51/46
Filed: 1938-09-22
Abstract: 518,393. Caps for bottles and the like. FARRER, J. O. (Continental Can Co., Inc.). Sept. 22, 1933, No. 27691. [Class 125 (iii)] Centre spots for crown caps are formed from fusibleadhesive coated material by a punch unit to which the spot is held by evacuation of air pressure and which moves bodily in the direction of the length of the strip of material to feed it forward. The spot is carried through a heat zone and applied to the cap by pressure exerted by the punch unit and a blast of air through the unit. The table 5 supports a punch turret A, a transfer turret B, and a spot setting turret C which all rotate about vertical axes. The turret A has a rotor 12 secured to the shaft 6 and the periphery of the rotor has a number of bores in which punch sleeves 14 are reciprocable and are arranged above openings in a die plate or ring 15. Each sleeve 14 acts as guide for a plunger 24 secured by an actuator nut head 26 at its upper end while its lower end passes through the stripper finger 16 and the ring 15. Each sleeve 14 has an external thread 19 so that it is adjustable in the clamp bead 20 which has a roller 21 travelling in a cam groove. A spring 35 is arranged to force the plunger 24 upwards and the sleeve 14 downwards. Each plunger has a duct 29 which is in communication with a suction duct 31 for part of the turret revolution and in communication with a pressure duct 33 for another part: Crown caps 41 are fed by a shoot 42 to notches 40 in a ring 39 which is removably secured to the under face of the rotor 12. The strip 66 for the spots is fed to a pair of feed rollers 67 the lower of which is cooled in a liquid bath 68 to prevent the strip from becoming tacky. The strip then passes between drag rollers 69 to the punch unit. The drag rollers ensure that the strip remains slack between the rollers 67, 69. The turrets are rotated through gearing from the shaft 81 and the rotation of the turret A causes a punch to be operated by cam action to' descend and punch spot from the strip. The bore of the punch is connected to the suction duct to hold the spot to the punch and the movement of the turret carries the punch to feed the slack strip ready for the next punch. As the formed spot is carried forward it passes over gas burners 72 connected to the gas pipe 71 to heat the adhesive on the spot. The heating zone ends just before the point 77 where the crown caps are introduced from the shoot 42. At this point the punches start moving downwards until the heated spots are pressed into the caps and the connection to the suction duct is broken. The pressure by the punch is maintained and the punch bore is connected to the pressure duct; the air pressure continues until the punch rises and the spotted cap is delivered to the transfer turret B, The cap then passes to the carrier on the turret C where spring plungers 55 hold the spots in the caps under pressure for about three-quarters of a revolution of the turret, when the plungers are raised and the spotted caps are discharged, along the track 60.