To provide a DC motor never causing the stepping-out of a magnet coupling.

A starting current is limited by a circuit 40 in which a high resistor R is connected in parallel to a current limiting circuit built in a drive circuit IC 36 containing a control circuit of Hall elements 34u, 34v, and 34w attached to a brushless DC motor 16 to significantly increase the build up time of the brushless DC motor 16. Therefore, a drive magnet gently starts to rotate from a resting state, consequently allowing a driven magnet to rotate followingly at the same speed according to it. The rotation thus can reach a regulated rotating speed without stepping-out, and the pump device can be rotated in a normally stabilized state.