| 摘要 |
PROBLEM TO BE SOLVED: To obtain a driving device which enhances the high-speed rotation characteristic of a stepping motor by a method wherein one phase out of windings with N-phases is provided with an exciting sequence which can apply a power-supply voltage. SOLUTION: For example, in a five-phase stepping motor, an exciting sequence is given to an output part wherein five motor windings which are connected annularly and five sets of switching element groups are provided. Consequently, a current is made to flow to three or four windings out of the five motor windings. That is to say, when clock pulses are inputted, the exciting sequence is shifted by one pulse portion. Then, a phase which is excited is shifted to four phases→three phases→four phases→three phases. Then, when the number of the exciting sequence is an odd number, a current is made to flow to the three windings out of the five motor windings, and a state that a power-supply voltage can be applied to one winding out of the three windings is set. As a result, the frequency of the clock pulses is raised, and ths stepping motor is turned at high speed. When the current of the steeping motor is reduced, its reduction amount is reduced, and the high-speed rotation characteristic of the stepping motor can be enhanced. |
