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