| 摘要 |
<p>An automatic ticket stamping facility for use on public transport systems utilises a non-contact sensing stage. The ticket is inserted in a slot between a print roller (1) and a contact plate (2). The end of the ticket, which carries a magnetic surface coating, passes into the air gap (11) of an electromagnetic sensing unit. The sensor has a soft iron core (8), with a primary coil (14) wound onto it. A secondary coil (16) is obtained from a transformer stage and this controls the operation of the printer contact plate. Insertion of the ticket into the gap modifies the output of the secondary coil. A number of separate sensing coils responsive to different magnetic ticket zones may be used to generate an identification code.</p> |
