The Cessna Aircraft Company

Dennis R Unruh

Robert J Martin

This lower link for a three-bar hitch provides a practical way to determine the tension force present in a lower link independent of any bending or other loadings. The link is formed of two bars which are bent out from each other to an intermediate point and then converge together forming a diamond-shaped opening between the bars and the distance between the intermediate points on the bars is measured by a length measuring device; the length being translatable into the tension force on the link.

Force measuring device

This automatic hydraulic cushioning device for cam plate positioning actuators on variable displacement, axial piston pumps eliminates the noise, vibration, and wear caused by hammering of the positioning actuator on the back plate when the actuator is close to full retraction. A supply of fluid under pressure, which is available at the back plate, is channeled to the cam plate positioning actuator. A valve in the actuator blocks off drainage of the fluid whenever the actuator is close to its fully retracted position. This retained fluid becomes a hydraulic stop and cushion for the actuator thus eliminating the hammering as well as the noise, vibration, and wear which results from the hammering.

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Buhler, KS, United States of America

Dennis R Unruh