PURPOSE: To obtain a large revolving torque resulting in the fixed number of revolution by spirally arranging the S pole of a permanent magnet on a non-magnetic body rotating cylinder, disposing the N pole of the permanent magnet on the external surface of a semicircular non-magnetic substance plate and combining driving gears using both poles as magnetic teeth under the state of striding and sitting.

CONSTITUTION: Permanent magnets 2 are arranged continuously in rows along circumferences on the external surfaces of mounting frames 1 having a shape that the plate of a non-magnetic body is bent in a semicircular form, thus manufacturing driving gears 11. A permanent magnet 4 is disposed spirally and continuously on a non-magnetic body rotating cylinder 3, in which both sides of a shaft are supported by bearings, thus constituting a driven gear 12. The driving gears 11 are combined on the external upper section of the horizontally installed rotatable driven gear 12 in a striding and sitting manner at very short intervals, and held under the non-contact state, and the driving gears 11 are formed in horizontally movable structure. Accordingly, the number of revolution is kept constant with the increase of the diameter of the driven-gear revolution body 3 even at the time of constant linear moving length, thus obtaining a large revolving torque.