| 主权项 |
1. In a tire-building drum having a hollow main shaft having an end which is mountable upon a support for supporting the drum in a cantilevered condition above a floor, a plurality of circumferential segments about which a tire carcass can be constructed and which are movable between collapsed positions at which the drum is in a radially-collapsed condition and fully-expanded positions at which the drum is in a radially and fully-expanded condition, a drive rod which is positioned within and is axially movable along the length of the main shaft between a first condition and a second condition, and a swing arm which surrounds the main shaft and is connected between the circumferential segments and the drive rod so that axial movement of the drive rod along the length of the main shaft from the first condition to the second condition effects a rotation of the swing arm about the main shaft from a first position thereabout at which the drum is in its radially-collapsed condition to a second position at which the drum is in its radially and fully-expanded condition, the improvement comprising:
a mechanical assembly for acting between the swing arm and the main shaft so that upon rotation of the swing arm about the main shaft to its second position thereabout, the mechanical assembly biases the swing arm about the main shaft to continually urge the circumferential segments into the fully-expanded positions. |
