FLEXIBLE ENGAGING TYPE GEAR DEVICE HAVING THREE-DIMENSIONAL NONINTERFERENCE WIDE RANGE ENGAGING TOOTH FORM

摘要

PROBLEM TO BE SOLVED: To realize the accurate wide range engagement of teeth ranging the whole of a tooth trace even in the case where the number of teeth is few by considering the inclination of a tooth of a flexible external gear in a flexible engagement type gear device and the variation of a motion focus of the origin of tooth form coordinates. SOLUTION: A compound curve BCD is based on the movement locus approximated to a rack of a tooth of a flexible external gear to a rigid internal gear. A curve BC is an envelope to be obtained by axially overlapping the movement locus of each axial rectangular section from an opened part to near an inner end part, and the movement locus 1e of a tooth of the flexible external gear having A-point in the axial rectangular section of the opened part as the top is smoothly connected at the B-point of the curve BC, and the B-point also functions as an inflection point of the locus of the opened part 1e. A curve CD is a part of a movement focus 1i in an axial rectangular section near an inner end part and smoothly connected to the curve BC at a C-point. D-point is a point where a distance in a tooth height direction from a middle point O between A-point and B-point is twice as far as the tooth height of an common addendam of both the gears. Thus the tooth formes do not cause an interference.