| 摘要 |
An apparatus comprises a frame (14) and a transport assembly (10, 110, 210) supporting the frame (14). The transport assembly (10, 110, 210) is configured to selectively move relative to the frame (14) between a transport position and a brake position. A portion of the frame (14) frictionally engages a portion of the transport assembly (10, 110, 210) in the brake position to affect a brake application that resists the transportation of the frame (14). The portion of the frame (14) is disengaged from the portion of the transport assembly (10, 110, 210) in the transport position to allow for transportation of the frame (14). |
