| 摘要 |
1,127,039. Telegraphy. ING. C. OLIVETTI & C. S.p.A. 9 Dec., 1966 [24 Dec., 1965], No. 56311/66. Heading H4P. A mechanism for adjusting the timing of the selector cams relative to received start-stop signal elements in a teleprinter comprises a stop lever 14 which, when released by a release lever 36, permits one revolution of the receiver shaft 7 which carries the cams 20. The stop lever 14 is mounted on a plate 51 which is positioned manually about the shaft 7 to adjust the stop position relative to the cams. An intermediate member 46 carried by a lever 18 is engaged by an arm 40 of release lever 36 and an arm 45 of the stop lever 14 such that there is a substantially constant ratio between the effective length of these arms. General operation.-When the Start element is received electromagnet 24, Fig. 1, releases armature 27 so that lever 31 moves anticlockwise. Pin 38 is now released so lever 36 moves clockwise. Arm 18 thus moves anticlockwise, engaging roller 46 with arm 45 of stop lever 14. Lever 14 moves anticlockwise releasing arm 12 and so allowing shaft 7 to rotate. Cam 49, Fig. 4, moves lever 48 clockwise during the stop element, hence tensioning spring 16 and returning the stop lever to rest and thus preventing more than one revolution of shaft 7. In addition arm 50 of lever 14 engages roller 46 to return lever 36 to rest. Adjustment.-A manual arrangement, Fig. 3 (not shown), permits variation of the position of plate 51 which carries the stop lever 14 and lever 48. This variation also causes variation in the position of the pivot 19 of lever 18. Movement of the stop lever pivot permits corresponding movement in shaft 7, so advancing or retarding cams 7 relative to the selector levers 21. The relative movement of the pivot points is such that the effective length of arms 40, 45, and 50 remain substantially constant; this ensures that the release torque imparted by lever 36 to lever 14 is constant. The receiver can be set to operate at a higher speed, in known manner, by operating lever 77. This also brings into operation mechanism for returning armature 26 to the stop position independently of the received stop element. At the end of the revolution of shaft 7 cam 82, Fig. 4, rotates lever 72 clockwise. Lever 86 is moved anticlockwise and pin 89 moves lever 31 clockwise so restoring armature 26. |
