GB1102904A - Tire curing press - Google Patents

Abstract

1,102,904. Moulding tyres. NRM CORPORATION. 13 July, 1965 [28 Sept., 1964], No. 29691/65. Heading B5A. A tyre press for curing radial cord tyres, in which a tyre band is placed over an inflated bladder and held between upper and lower moulds 1 and 2 respectively, includes radially movable tread sectors 101 which, when the moulds 1 and 2 are brought into moulding position, are urged radially inwardly by a cam and lever mechanism to abut steps 41 and 21 of the moulds. The upper mould is attached to a platen 3 carried by a bolster 115 attached to the upper vertically and laterally movable part 123 of the press. Relative vertical movement between the bolster and platen is provided by a number of air springs 137 on rods 142 which urge the bolster upwardly to abut the heads 134 of screws 130. An annular housing 46 depending from the platen has circumferentially spaced openings therearound in each of which a block 86 attached to a tread sector is radially slidable. A lever 70 is pivoted at 80 to each block and at 68 to the housing 46, and carries a pin 77. When the moulds 1, 2 are brought into their operative position with the lower surfaces 107 of the sectors 101 in engagement with the surface 22 of the lower mould, further downward movement of the part 123 forces the bolster downwardly relative the platen 3. Cam members 148 circumferentially spaced around the bolster are thereby caused to engage the pins 77 which pivot the levers and force the tread sectors radially inwards. An annular plate 153 around the bolster carries pairs of lugs 156, one pair for each sector, which engage behind the sector blocks 86 to lock them in their radially innermost positions. After the moulding process and when the part 123 is raised, the lugs 156 engage the pins 77 to pivot the levers in the opposite direction and move the tread sectors radially outwardly. In the moulding position the tyre beads engage upper and lower rings 25 and 12, the upper ring forming part of a vertically adjustable assembly including a bladder ram 32 which, after moulding, moves down to force the bladder 18 into a well 16; simultaneously, plates 29 are moved radially outwardly by a pivoted link mechanism to below the upper bead of the tyre. This ensures that the tyre is carried upwardly with the upper mould after treatment. A tube 28 of the assembly is then moved downwardly and the ring 25 is lowered from the upper mould, causing the tyre to be stripped therefrom. The plates 29 are then retracted and the tyre drops away from the press.