| 摘要 |
<p>A scroll displaying mechanism (1) suitable for use in moving advertising displays, chart recorders and tape readers uses a pair of D.C. motors (18, 19) wired to operate under slightly different speed-controlling voltages in order to maintain the displayed part of the scroll (2) between two rollers (5, 6) taut. A simple belt and pulley drive mechanism for each roller assures quiet and vibration-free operation. The viewing time between frame-advance and the scroll direction reversal are controlled by detection of different length markers (36) positioned along one edge of the scroll. Also disclosed is a simple, easily assembled and disassembled display apparatus (100) which allows both vertical and horizontal adjustment of the size of the viewing window frame, and a roof-mounted model (146) featuring oppositely-faced twin display windows.</p> |
