DECELERATION MECHANISM AND MOTOR HAVING DECELERATION MECHANISM INSTALLED THEREIN

摘要

According to the present invention, one engagement protrusion part 31c having a spiral shape is provided in a pinion gear 31, a plurality of engagement recess parts 32d engaged with the engagement protrusion part 31c are provided in a helical gear 32, and the engagement protrusion part 31c and the engagement recess parts 32d are each formed to have an arc shape in a direction perpendicular to the axial direction of the pinion gear 31. As a result, the pinion gear 31 and the helical gear 32 can be configured in an arc-shaped protrusion/recess engagement structure that does not deteriorate the state of engagement therebetween. Also, by increasing the number of teeth on the helical gear 32 while keeping the number of teeth on the pinion gear 31 at one tooth, the difference in the number of teeth can be easily increased. Therefore, the deceleration ratio of a deceleration mechanism 30 can be increased without increasing the volume thereof.