To drastically reduce the input torque by constituting a drastically shifted and enhanced gear.

This shifted gear is provided with a standard gear 2, a gear which has a same pitch diameter as that which is not illustrated here, has a thin tooth, and is shifted negatively, and a - shifted gear 4 having similar shape thereto, and a + shifted gear 3 which is engaged with the teeth and drastically shifted positively. The standard gear which is not illustrated here is assembled concentric with the + shifted gear center 5, and when the -shifted gear 4 is set to the input, the enhanced rotating force is generated in the standard gear. Where, the illustrated 4 kinds of the gears have same number of teeth.