| 摘要 |
<p>796,316. Electric selective signalling. BENDIX AVIATION CORPORATION. Sept. 28, 1954 [Oct. 2, 1953], No. 28002/54. Class 40 (1). An object is positioned along a closed path along which a number of discrete positions are designated by numbers expressed in binary code, the sense of movement corresponding to the shorter distance of travel from the actual to the desired positions being automatically selected. In one embodiment, a shaft 20, Fig. 1, is to be rotated into any one of sixteen positions represented by the four-digit conventional binary numbers 0000, 0001, 0010, &c., Fig. 4. Rotation is effected by a reversible motor 21 having clockwise and counterclockwise input busses MR, ML, respectively, which are selectively connected by circuit 24 to a current source 23. The actual angular numerical position of the shaft 20 is set up on relays PR1 ... PR4, which are energized from source 34 through the contacts on a coding switch 25, rotating with the shaft 20, and brushes 30 ... 33. The " ordered " numerical position is set up on relays OR1 ... OR4 over signal lines L1 ... L4 from the transmitter, which may comprise a shaft having a coding switch such as 25. In one arrangement of the relay contacts in circuit 24 they fall into groups A ... D, Fig. 2, comprising the contacts of pairs of relays PRI, OR1, ... PR4, OR4, respectively, which in the upward position represent the digit O and in the downward position the digit 1. If the first digits of the actual and ordered numbers are the same the source 23 is connected to the output K of group A and, if they are different, to output L, these outputs forming the inputs of group B. Groups B, C and D are similar and compare in pairs the second, third and fourth digits of the actual and ordered numbers. For example, in group B if the second digits are the same inputs K and L are connected to outputs K and L respectively. When K is energized it is connected to the bus MR to energize the motor 21 clockwise if the digits are 01 and to the counterclockwise bus ML if the digits are 10. When L is energized, digits 01 connect it to ML and digits 10 to MR. The motor and shaft are thus driven to the ordered position by the shortest route until all the compared digits coincide when the source 23 is connected only to one of the terminals STOP to energize a motor brake or indicator lamp L.</p> |
