| 摘要 |
PROBLEM TO BE SOLVED: To provide a motor drive control device capable of stably performing motor drive control even in startup or under a high load, an electric tool and a motor drive control method.SOLUTION: An impact driver 1 comprises: a motor 3 including a rotor 3a and a stator 3b including a coil 3c; a Hall IC signal detection circuit 23 for detecting a rotation position of the rotor 3a on the basis of position detection signals outputted from Hall ICs 19i, 19j and 19k; and an induction voltage detection circuit 24 for detecting the rotation position of the rotor 3a on the basis of an induction voltage generated in the coil 3c. The impact driver 1 also comprises a motor current detection circuit 21, a motor rotation speed detection circuit 25 and a trigger manipulated variable detection circuit 22 for detecting a driving state of the motor 3. In accordance with the detected driving state, a microcomputer 26 switches the Hall IC signal detection circuit 23 and the induction voltage detection circuit 24, detects the rotation position and controls supply of a driving voltage from an inverter circuit part 7 to the motor on the basis of the detected rotation position. |
