| 摘要 |
1,120,599. Selective signalling. INTERNATIONAL STANDARD ELECTRIC CORP. 12 Aug., 1966 [19 Aug., 1965], No. 36146/66. Heading G4H. The outputs S1, S2 from a two-phase resolver, Fig. 1, are so combined, by phase shifting circuits, as to produce two signals 16, 17 which respectively lead and lag the phase of the reference signal applied to the resolver rotor by an amount proportional to the angular displacement of the resolver rotor from its reference position (equally inclined to both stator windings), and their phase difference is digitized by using their zero-crossovers to start and stop the counting of relatively high frequency clock pulses. The counter indication is held steady for a short period before being reset 250 times per second. A three-phase synchro followed by a Scott transformer could be used in place of the twophase resolver, and the output of the counter could be converted into an analogue voltage. |
