Apparatus for turning up the axially outer ends of carcase plies on a tyre building drum

摘要

1,067,641. Tyre building apparatus. CONTINENTAL GUMMI-WERKE A.G. June 8, 1964 [July 30, 1963], No. 23611/64. Heading B7C. Tyre building apparatus comprises a cylindrical drum 1 upon which carcass plies are located, and a coaxially disposed annular airbag secured at its edges and adapted to turn the axially outer ends of the plies around the tyre bead cores 21, at least one edge 7 of the air-bag being displaceably secured to a ring member 9 axially movable with respect to the tyre building drum. The edge 7 of the air-bag is housed within a radially extending slot 8 in the ring member 9, the second edge of the airbag being clamped to the radially outer periphery of an annular disc 4. The drum 1 and members 4, 9 are mounted on a tube 2 which also carries a bead core positioning device comprising two rings 12, 13 displaceable telescopically relative to each other. The ends of the carcass plies are pushed radially inwards around the drum shoulder by means of grippers 15, 16 which are interconnected by annular rubber bodies 18, 19, respectively. The bead core 21 is then advanced against the carcass plies by means of the rings 12, 13. Initial inflation of the annular chamber formed by the air-bag 5 and the members 4, 9 causes the edge 7 of the air-bag to move radially outwardly in the slot 8. Further inflation causes the member 9 to move away from the disc 4 against the action of a spring 11. The air-bag thus moves radially inwardly of the bead core 21, lifts the extreme end 20SP1/SP of the carcass fabric and finally displaces the ring 13 against the action of a spring 14. The rings 12, 13 may then be completely withdrawn and the air-bag further inflated, the grippers 15, 16 being used as an abutment to force the air-bag and hence the end 20SP1/SP of the carcass fabric against the drum 1.