| 摘要 |
<p>An apparatus (10) for rotating a drum (12) employs a plurality of drive sprockets (20) disposed about the outside surface (14) of the drum (12) and spaced-apart along the length of the drum (12). Each drive sprocket (20) has a first flange (22a), a second flange (22b) and a plurality of pins (24) interconnecting the first flange (22a) and the second flange (22b), spaced-apart about the drum (12) and parallel to the axis (16) of the drum (12). Spaced-apart hydraulic rams (30) each exert a force on one of the drive sprockets (20) so as to cause rotation of the drum (12). Each ram (30) is movable between a linearly retracted first state (A) and a linearly extended second state (A') and has a first end (34) and an opposite second end (32). The first end (34) is secured to the base (18), the second end is engageable with the pins (24) of a selected drive sprocket (20) so that as the ram extends from the first state (A) to the second state (A'), the ram exerts force on a pin (24) in the first direction (B), the first direction (B) being tangential to the outside surface (14) and perpendicular to the axis (16) of the drum (12). Force from the rams (30) is transferred to the drum (12) through the pins (24), the first flange (22a) and the second flange (22b). A plurality of spaced-apart ratchet stops (40) prevent movement of the drum (12) in a direction opposite the first direction (B). Torque applied to the drum (12) by the rams (30) is distributed along the length of the drum (12) at each of the plurality of drive sprockets (20).</p> |
