| 摘要 |
An improved folding ring for a tyre building drum for folding the tyre cord reinforcing plies round the bead wire, in which the helical springs (12) between the spreader levers (9) are supported on rings (14) which in turn are free to rotate with the journal (14) passing through the end of the spreader lever (9). The rings (13) are prevented from rotating on the journal or from axial displacement by the pins (15). The method of support of the springs which allows free rotation, prevents the sticking and frequent spring spring failure in known arrangements. |
