| 摘要 |
<p>983, 598. Electric selective signalling. POTTER INSTRUMENT CO.Inc. April 12, 1962 [April 26, 1961], No. 14220/62. Heading G4H. A high speed printer comprises a number of type rings together forming a type drum 1. The drum is driven continuously and carries a tone wheel 5 which has teeth such that a clock pulse is developed by pick-up 11 each time a new character is positioned beneath the printing hammers 7 (only one shown). The tone wheel has an additional tooth which provides a "start" pulse during the printing cycle. The start and clock pulses are separated by unit 60, Fig. 3 (not shown), and are used in unit 35 to control the type hammers, this unit being fed with positional data from an external source. Pressure sensitive paper is used.</p> |
