| 摘要 |
<p>1,075,036. Electric selective signalling. DEMAG-ZUG G.m.b.H. May 13, 1965 [July 24, 1964], No. 20328/65. Addition to 1,074,336. Heading G4H. In a digital control device, a counter with five two-state stages supplies actual value signals to AND gates which also receive desired value signals via diodes, the outputs of half the AND gates being connected to a " forward " output and half to a " reverse " output, the "reverse" AND gates being closed to all actual value 1-states corresponding to a numerical value less than or equal to the desired value and the " forward " AND gates being closed to all desired value 1-states corresponding to a numerical value less than or equal to the actual value. A feedback positioning system incorporates the above arrangement for one decimal order, similar arrangements being provided for the other orders. The direction of the positioning motor is controlled by the " forward " and " reverse " outputs of the highest decimal order in which the desired and actual value digits are unequal, by means of inverters and OR gates (e.g. Fig. 2, not shown). Triggers (T1, T2, T3, Figs. 1A, 1B, not shown) respond to the number of AND gates producing a 1- output, and, together with " forward " and " reverse " signals, control logic circuitry (e.g. Fig. 3, not shown) to allow the positioning motor as the end-point is approached.</p> |
