To obtain a mechanism in which a disk with a permanent magnet is rotated by a mutual action of the permanent magnet and an electromagnet and a simple construction is provided so as to be easily made and smoothly, continuously rotated at high speeds and in which rotational speeds can be varied in a non-step manner and moreover a simple motor whose performance can be maintained for a long time can be made.

Several permanent magnets are attached to the periphery of a circular plate (disk) of thick paper or plastics to form a rotor 1 which is rotated by a mutual action between the magnets and an electromagnet. In that case, magnetic forces of the electromagnet is controlled by utilizing a lead switch 4 which acts by sensing magnetism, whereby the rotor is rotated while the timing of the mutual action of magnetism is being maintained. As a result, high speed rotation can be smoothly maintained so that a simple motor whose rotational speeds can be varied in a non-stop manner can be made. And an ON/OFF operation of the electromagnet effected by turning on or turning off the lead switch can be visually checked.