Real-time measuring device for variable pitch angle of propeller blade

The invention relates to a real-time measuring device for a variable pitch angle of a propeller blade. The device comprises a cam, a push rod assembly and a displacement sensor; the cam is arranged inthe root of the propeller blade and rotates with the blade in an integrated manner; the push rod assembly comprises a push rod, a universal ball bearing, a casing and a spring; the universal ball bearing is mounted at one end of the push rod, the other end of the push rod is positioned in the casing, the push rod is in sliding fit with the casing, the spring is arranged between the push rod and the casing and acts an elastic push force on the push rod, and under the effect of the elastic push force, the universal ball bearing at one end of the push rod abuts against the cam always; and the displacement sensor monitors a sliding displacement of the push rod in real time. A cam-push rod-indicating disc-displacement sensor contact measuring scheme is employed, and a current vortex sensor isused to measure the propel