摘要 |
<p>908,179. Electric selective signalling systems. STANDARD TELEPHONES & CABLES Ltd. May 8, 1959 [May 14, 1958], No. 15881/59. Drawings to Specification. Class 40 (1). In a shaft-digitizer ambiguous indications from a coded scale are avoided by using two identical (except as mentioned below) coded scales displaced angularly with respect to each other by half of the smallest scale division, one of the scales carrying an additional track which selects which of the two coded-scales is to be used for indicating the shaft position for every position of the shaft. The scales can be sensed either photo-electrically or by brushes.</p> |