Improvements in or relating to electronic measuring apparatus

摘要: 762,499. Selective signalling by counting impulses. BRITISH TABULATING MACHINE CO., Ltd. Oct. 22, 1954 [Nov. 30, 1953], No. 33174/53. Class 40 (1). [Also in Group XL (b)] A shaft, e.g. of a weighing machine, signals its position sending impulses to counter which is stepped one direction for clockwise and the other counter-clockwise rotation shaft. Discrimination between two directions obtained causing shaft generate sets quadrature, deriving from set trains corresponding respectively dark-to-light light-to-dark transitions rendering or train effective control trigger-circuit accordance with relation set. As shown, carries disc rings alternate opaque transparent portions cooperating lamp photo-cells 1, 2 arranged on radius. It will be seen that when rotates clockwise, cell 1 take place light conversely, moves counterclockwise, transitions. The same effect can produced single obturating ring staggered. polycathode discharge tubes. Discriminating arrangement. Each lightto-dark transition made produce short + impulse line 17 each dark-tolight 18. either way produces an 19 these bi-stable circuit 5 so it state while opens gates 6 7 dark. Accordingly, 6, open, reach trigger 8 via 20 21 according as counter-clockwise. Circuit determines whether gate 9 10 shall open readiness at 2. An thus sent pair scale marks 24 25 rotation. Counter circuit. Impulses operate units 53 known manner. When passes electrode 0, lefthand half valve 50 conducts right-hand cut off. negative passed left-hand 52 cause conduct provided equipment adding determined bias voltage 22 furnished 8. " add then given tens tube 54. If subtracting, cessation 0 changes over resulting causes 51 biasing subtract". subtract "-impulse tube.