| 摘要 |
1. Device for successively presenting messages, of the type comprising a soft film E serving as a support for the messages and the ends of which are fixed to and are adapted to be wrapped around and unwrapped from two lower rotating cylinders A, B with parallel axes, disposed at neighbouring heights and coupled to a driving member allowing one cylinder A, B to be charged when the other is discharged and vice-versa, means being further provided for organizing the passing-by of the film and defining the periods of exposure, the said film passing around a third cylinder C, rotatably mounted above the said two cylinders, so that the two film ends suspended on either side of said third cylinder equilibrate each other, said driving member comprising at least one motor M coupled to said two lower cylinders A, B by means of at least one transmission element 9 and two respective, preferably electromagnetic, coupling means 4-7, 8, 6, characterized in that the passing-by is stopped by stopping the motor M and by putting the two disconnection means 4-7, 6-8 into the connected state, so that the two cylinders A, B are fixedly connected, preventing any untimely movement of the film E in whatsoever direction. |
