| 摘要 |
<p>Information is stored on document sheets which are slotted into envelopes formed in a long roll of transparent plastics material. The roll may be moved by a motor to bring to a chosen position any of the documents stored in the pockets in it. The control system associated with the motor allows automatic reversal of the motor direction under the control of a time switch, and also automatic reversal on reaching the end of the roll. Documents may be advanced one by one, and may also be selected by the operator overriding the automatic controls. Using a counter, documents may be located automatically, and the number of the selected document displayed. The sequence of operation and the priority of particular functions may be altered according to the operators requirements. Normally, the priority of the operations is start, selection, forward or reverse motion and automatic feed-through.</p> |
