GB1386760A - Segment moulds for vulcanizing tyres - Google Patents

Abstract

1386760 Moulding tyres G GAZUIT 4 May 1973 [4 May 1972] 21375/73 Heading B5A A tyre vulcanizing mould includes sidewall mould members 12, 17 and radially movable segments 3, each of the latter composed of parts 19, 20 joined by screws 26, 27 allowing slight movement therebetween, and an annular bladder 29 housed between the segment parts. When the mould is almost closed pressure fluid is supplied to the bladder causing the parts 20 to move radially inwardly a further slight amount to exert pressure on the tyre. The major radial movement of the segments is effected by a ring 4 which includes, for each segment, a lug 6 with a cam slot 7 in which a stud 8 on an arm 9 extending from a segment engages. Partrotation of the ring by a ram 5 effects segment movement. Fig. 4 shows the segments in their radially inner positions in which a slight clearance is provided between opposed surfaces 4a, 19a of the ring and the segment parts 19; when pressure fluid is supplied to the bladder 29 such surfaces are brought into abutment and the parts 20 are moved inwardly to bring surfaces 24 into abutment with surfaces 25 of the members 12, 17. In a modification, Fig. 7, not shown, the lower mould part is divided into separate elements with a space therebetween housing an annular bladder into which pressure fluid is fed when the mould is closed, causing the tyre sidewalls to be additionally pressurized. In the mould-closed position the mould part 2 is locked to the ring 4 by a bayonet connection 37, 38.