| 摘要 |
<p>1. Demonstration screen with several blackboards which can be slid in upper and lower guide rails (2, 3) running horizontally and with a projection screen that is supported so that it can be tilted on its lower edge (4) behind the plane of the rearmost guide rails, characterized in that projection screen (1) has a tilting device (10) near its upper edge (7), by means of this tilting device (10) the upper edge (7) of the projection screen (1) is capable of swivelling in front of the frontmost, upper guide rail (2) and that the projection screen (1) has a lifting device (16, 12) for the vertical adjustment of the projection screen (1).</p> |
