| 摘要 |
976,332. Electric selective signalling systems. INTERNATIONAL BUSINESS MACHINES CORPORATION. Nov. 18, 1963 [Nov. 19, 1962], No. 45356/63. Heading G4H. A shaft-position digitiser in which a pair of brushes 13, 14, Fig. 1, are sequentially brought into contact with contacts 12 is characterized in that a diode recoding matrix 15 is printed on the disc which supports the contacts 12. Two brushes 13, 14 are used instead of one to prevent "dead" zones and to prevent ambiguities. They are so arranged in a transistor circuit Fig. 6 that brush 13 is normally earthed (via 21) and brush 14 inoperative and so that as soon as brush 13 leaves a contact 12 brush 14 becomes earthed (via 22) and thus constitutes the operative brush. |
