| 摘要 |
<p>The controller has a control unit (1) which is carried by the motor stator and supplies the coils in the stator. The unit produces PWM signals in which simultaneously the period of the signal gives speed information and the mark-to-space ratio gives direction information along a single input wire (3) to a receiver unit. Typically, a mark-to-space ratio equal to one would represent a transition in direction while the frequency might be 3 200 Hz. In the receiver, a frequency divider (9) produces the clock signals from the modulated signal which is also fed through an RC integrating filter (7) to Schmitt comparators (8). The comparators compare the ratio to one or more thresholds representing a change of direction of rotation and blocking of the supply to the coil or coils.</p> |
