Abstract: In previous researches, Grashof Neutral mechanisms are usually considered that when they come its change points, the transmission ratio will become to 0/0 and then the output motion will be uncertain. Based on the continuity of mechanism motion and the L￠Hospital￠s theorem, the transmission ratio at the change points of the mechanisms are analytically derived and through the kinematic analysis, simulation and experiments, it is demonstrated that the rotating mechanisms will smoothly pass through its change poins with certain speed and make the driving crank rotate two turns in a period of motion. Further, when the links have nearly same length, the mechanisms can output intermittent motion with a long pause and self-locking characteristic, they are useful for industry.

Key words: Change point, Grashof, Intermittent motion, L'Hospital's theorem, Neutral mechanism, Period of motion, Lamb wave, Lift-off distance, Lorentz force, Magnetostriction force, EMAT