Patent ID: 8061229

Claim:
A gear drive comprising: a first toothed wheel and a second toothed wheel with τ 1 and τ 2 tooth pitch angles of interacting toothed crowns, with single-flow elements or with multi-flow elements with relative angular offsets τ p1,2 1-2 of like engagement phases of successively interacting pairs of said toothed crowns, having face tooth profiles including piecewise conjugate and/or pointwise conjugate convex at a tooth addendum and concave at a tooth dedendum at points of their theoretical contact, extra-pole arc-shaped sections continuously connectable to each other or to other sections; characterized in that said interacting toothed crowns are arranged with face overlap angles φ a1,2 less than said tooth pitch angles τ 1,2 or said relative angular offsets τ p1,2 1-2 , with creating a gap between phases of tooth intermating equal to a discrete intermating angle φ D1,2 whereat τ p1,2 1-2 =0 or φ D1,2 1 whereat τ p1,2 1-2 ≠0 from a disengaging point of said teeth face profiles N 2 , to an engaging point of said teeth face profiles N 1 , wherein minimum one said phase is formed by said extra-pole arc-shaped sections and said drive has a tooth face overlap ratio ε α <1 or a total overlap ratio ε γ <1.