| 摘要 |
<p>A marking pattern (21) is provided on a lead screw (7) in parallel with the thread of the lead screw. A carriage (3) driven along by the lead screw (7) contains a transducer (25) for sensing the marking pattern on the lead screw to produce electrical output signal pulses indicative of incremental displacement of the carriage (3). A printhead (1) can be mounted on the carriage (3) and the electrical output signal pulses from the transducer (25) used to control printing operations. The marking pattern (21) can be designed to provide control signals for other purposes, for example for controlling start-up, running, deceleration and reversal of a motor (9) driving the lead screw (7).</p> |
