| 摘要 |
A device (1) for covering a surface (3) has a drum (2) mounted to rotate and able to wind up or unwind a cover (10). Two flexible belts (31) are fixed at their ends (35) to the four corners of the surface that is to be covered and arranged along the perimeter of the surface. A carriage (21) transversely overhangs the surface (3) and supports the drum. The carriage has at each end a drive wheel and at least two casters allowing for the longitudinal translational movement of the carriage together constituting a triangle of which the drive wheel forms the vertex. Sections (31a) of each flexible belt between their ends and the casters, are pressed against the length of the periphery of the surface, and so that the section (31b) of each belt between the at least two casters (33) runs over the drive wheel (9) without slipping. |
