Abstract: A Prony brake used as a rotational load absorption unit, or dynamometer, to measure power output of a prime mover includes a cylindrical tube disposed within a sealed tank containing coolant water. Disposed within the cylindrical tube is a fixed stator shaft, which is attached to the center of a stator plate having its outer periphery disposed in closely spaced relation to the tube's inner surface, with the stator shaft further coupled to a hydraulic control system. Disposed within the stator plate's outer periphery are plural radially spaced pistons for applying a radially outward friction braking force to the inner surface of the rotating cylindrical tube. The stator shaft is provided with first and second ports and passageways for respectively transporting hydraulic control fluid and lubrication fluid. Also included is a supplemental cooling water supply wherein cooling water is circulated with the Prony brake by the rotating cylindrical tube.

Abstract: A Prony brake used as a rotational load absorption unit, or dynamometer, to measure power output of a prime mover includes a cylindrical tube, or drum, disposed within a sealed tank containing coolant water. Disposed within the cylindrical tube in a sealed manner is a fixed stator shaft. The stator shaft is attached to the center of a generally circular, planar stator plate having its outer periphery disposed in closely spaced relation to the tube's inner surface, with the stator shaft further coupled to a hydraulic control system. Disposed within the stator plate's outer periphery are plural radially spaced pistons responsive to the hydraulic control system for applying a radially outward friction braking force to the inner surface of the rotating cylindrical tube. The stator shaft is provided with first and second ports and passageways for respectively transporting hydraulic control fluid and lubrication fluid.