| 摘要 |
PURPOSE:To flow currents having gentle edge variation to the coils of the commutatorless motor to prevent the generation of noise by a method wherein the signals having gentle edge variation are supplied time-divisionally according to the change-over timing to a plurality of switching elements. CONSTITUTION:Position detection signals (a), (b) outputted from Hall elements HG1, HG2 receive wave shaping by a control circuit 1 to form a signal (c), and is supplied to T type flip flops FF's 2, 4 directly and through an inverter 3. Outputs of the FF's 2, 4 are converted into a signal (g) by passing through a NAND gate 5, and is inputted to an integration circuit 6 through resistors R1, R2, transistors Tr1, Tr2. Output (e) of the integration circuit 6 is supplied to a switching circuit 8 through an amplifier 7, while output thereof is used as the reset signal (f) of the FF's 2, 4 through an amplifier 9. Moreover the control circuit 1 outputs switching signals (h)-(k) corresponding to rise of the signal (g). Accordingly, the transistors Q1-Q8 are made to ON, OFF time-divisionally corresponing to the signals (e), (h)-(k), and currents (l), (m) are flowed to the coils 10a, 10b. |
