| 摘要 |
The stepping motor of a car dashboard clock includes a rotor with a number of magnets attached to it and a stator presenting a magnetic circuit with a coil. The power supply of the coil controls the rotor rotation. A device for controlling the direction of this rotation includes an ASIC which generates a power supply signal with three characteristic time intervals (t1,t2,t3). During the time t1 the signal applied to the stator coil produces the rotation of rotor in its normal direction. This short time interval enables the rotor to be unlocked from its position relative to the stator magnetic circuit. During the next time interval, t2, the sign of the control signal is reversed so that the rotor moves in the opposite direction. During the last time interval (t3) the rotor rotates in the normal direction to be again locked by the stator magnetic circuit.
|
