Rotational speed control device and rotational speed control method for brushless DC motor per minute

摘要

Apparatus for controlling the number of rotations per minute of a brushless DC motor, the apparatus comprising: a brushless DC motor that rotates at a constant speed when a rotation current is applied, and stops rotating when a stop current is applied; a pulse applying unit that outputs input pulses according to a pulse apply frequency, which is predetermined or inputted by a user; a rotation detecting unit that detects the number of rotation pulses, and outputs a predetermined output signal per rotation of the brushless DC motor; and a current controlling unit that applies the rotation current to the brushless DC motor in correspondence with the input pulse, and the stop current to the brushless DC motor in correspondence with the output signal.