Life Fitness, LLC

Zhenyu Tian

Joseph Gajewski

William J Kreuger

Thomas M Niec

An exercise machine has a first frame member, a second frame member that is movable with respect to the first frame member, and a locking device having at least one cam that is rotatable into and between a locked position in which the cam abuttingly engages and thereby retains the second frame member in position with respect to the first frame member and an unlocked position in which the cam is spaced from and thereby frees the second frame member for movement with respect to the first frame member. The cam has an engagement surface with a contour that follows a logarithmic spiral curve defined by the following parametric equations: x(t)=r(t)cos(t)=aecos(t), and y(t)=r(t)sin(t)=aesin(t), wherein e is the base of natural logarithms and a and b are arbitrary positive real constants.

Growing community of inventors

Berkeley, CA, United States of America

Zhenyu Tian