| 摘要 |
The device comprises, in combination: an obturator 1 integral with the element whose movement is to be controlled and in which openings 4 are made; a generator L for signals at a frequency which can be transmitted by optical fibres; fibre-optic lines 7 to 15 determining, depending on the position of the obturator 1, the connection of the generator L to the receivers R1 to R4 which are provided with suitable circuits, so that required electrical signals are present at the output 5 or at the output 6 and are different depending on whether the obturator 1 is at rest and as a function of the speed when it is moving. Application especially in the railway field, for obtaining positive safety. <IMAGE> |
