| 摘要 |
<p>1,162,966. Selective signalling. SIEMENS A.G. 7 June, 1968 [12 Aug., 1967], No. 27327/68. Heading G4H. The length of thread 1 fed by a pulley 2 is measured by shaping and integrating 4 pulses from a Hall plate co-operating with a magnet 3 rotated by the pulley, so as to produce a D.C. potential corresponding to the speed of the pulley, which potential is applied to a variable speed motor 5 which drives a counting mechanism 6. The counter can be preset to a required length and used to control 7, stopping of thread feed when the required length has been fed.</p> |
