| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent any large influence on control of a lighting tool in an irradiation direction due to fluctuation of power supply to a stepping motor. SOLUTION: In an irradiation direction control device 1, a driver 4 for directing the irradiation of a lighting tool 5 to a desired direction comprises a stepping motor 6. When a detector 9 detects a power source voltage or current to be supplied to the stepping motor 6, the voltage or current is sent to a controller 3, thus limiting an allowable range of a rotating speed of the stepping motor 6. For example, the controller 3 stepwise or continuously defines the allowable range of the rotating speed of the stepping motor 6 according to a decrease in power source voltage or current. Otherwise, in the case where it is detected that the power source voltage of current is deviated from the predetermined range, the controller 3 stops the control of the stepping motor 6.</p> |
