Abstract: A method for forming an internal gear is provided comprising providing a powder metal preform workpiece, supporting the workpiece about its periphery, and roll forming said workpiece to produce a set of densified gear teeth of a predefined dimension.

Abstract: A dual plunger valve having nested inner and outer plungers seated within a bore in the valve housing. The valve housing has an inlet port and an outlet port fluidly connected by the bore and sealed from one another by the plungers which are biased towards respective sealing surfaces by a pair of nested biasing elements located between the inlet port and the outlet port. The outer plunger is slidable within the bore and has a lip extending inwardly therefrom. The inner plunger is slidable within the outer plunger between a sealed position and a second position wherein it is in contact with the lip. Pressure in the inlet port which is high enough to overcome the force of the biasing elements causes the inner plunger to slide within the outer plunger to its second position wherein the outer plunger will then begin to slide within the bore to remove the seal between the inlet port and the outlet port.

Abstract: A hydraulic pump has a pair of inlets each with a pair of outlets. The inlets and outlets are arranged to balance the forces on the motor. The flow from the outlets of each pair may be combined to maximize flow or separated to reduce power consumption by recirculating the flow from the outlet to the inlet.

Abstract: A spur pump gear system comprising; a housing have a sealed chamber communicating with an intake port and a discharge port; a shaft journalled for rotation within said chamber; a drive spur gear mounted concentrically on said shaft about a first axis within said chamber, said drive spur gear presenting epi and hypo cycloid tooth profiles; a driven spur gear disposed internally within said chamber for rotation about a second axis, said driven spur gear presenting epi and hypo cycloid tooth profiles; said epi hypo cycloid tooth profile of said drive spur gear engagedly driving said hypo cycloid tooth profile of said driven spur gear.

Abstract: This invention relates to a porting system for a hydraulic device comprising a housing having a chamber communicating with an intake port and an exhaust port; a pair of rotary gears disposed internally of said chamber adjacent said ports and defining expanding and contracting pockets as said gears rotate over said intake and exhaust ports; said ports having a cross-sectional area in the direction perpendicular to the rotation which varies in relation to the rate of change of the expanding and contracting pockets.