Carriage shift mechanism for an electric typewriter

摘要

A cam loosely mounted on a constantly rotating drive shaft is normally held stationary independently of the drive shaft rotation and is permitted to rotate through a prescribed angle upon depression of the shift key or shift lock key of the typewriter. This rotary motion of cam is translated into the upward displacement of the typewriter carriage via a linkage coupled to a rail slidably supporting the carriage thereon. The linkage is further operatively coupled to a toggle joint mechanism adapted to assist the up-and-down motion of the carriage.