A lever mechanism for exerting variable torque about the axis of a valve spindle in which a stationary abutment member, a movable abutment member rotatable with the spindle, and a pivot pin are mounted on a valve with a lever arm which provides an initial mechanical advantage between the lever and the spindle until after some rotation has occurred, spindle and lever move in unison with a final mechanical advantage, the initial mechanical advantage being greater than the final mechanical advantage.
A linkage, particularly for an aircraft control surface utilizing an arrowhead cam and a follower member. The shape of the arrowhead in cooperation with the location of the pivot points of this cam and of the follower predetermines the output motion of the follower in response to input motion on the arrowhead cam. The linkage produces a variable gain; i.e., a different output response at the follower for the same increment of input motion at different places in the total range of input motion.
A valve control linkage is disclosed which provides a variable rate of relative motion between a valve spool and a control lever. The relative rate of valve spool displacement with respect to the lever motion is lowest adjacent the neutral position of the lever.
