Stepless speed change device

In a stepless speed change device including an internally toothed ratchet formed in an inner circumference of a driving rotary body, and a plurality of pawls whose distal end engage said teeth of said internally toothed ratchet and bottoms of said pawls being pivotally connected to a driven rotary body rotatably provided on an eccentric cam assembly whose eccentricity is adjustable, thereby deriving output at the driven rotary body, said eccentric cam assembly consisting of an inner eccentric cam substantially in the form of a cylinder and an outer eccentric cam substantially in the form of a cylinder snugly rotatably fitted on said inner eccentric cam, said inner and outer eccentric cams being rotated relative to each other to change the eccentricity of the cam assembly, the improvement comprising a floating ring having an inner diameter smaller than a root diameter of teeth of said internally toothed ratchet and arranged in floating condition in side-by-side relation to said internally toothed ratchet and permitting said distal ends of said pawls to inscribe said floating ring.