Abstract: A control circuit and specific embodiments thereof are provided using a four-port infinitely variable pilot operated pressure-compensator spool valve and a three-port infinitely variable pilot operated load sense spool valve in series to regulate the output pressure of a variable displacement radial piston pump. The valves are so constructed that both must be correctly positioned to put the pump into full stroke, while either valve can de-stroke the pump. The three-port valve is pilot controlled between the load sense pressure and the outlet pressure, while the four-port valve is controlled between the pump inlet and outlet pressures. A check valve and orifice are positioned between the two control valves and the crankcase control line of the pump to assist in stabilizing the pump output. A relief valve is provided on the crankcase line to minimize output spikes. In an alternative embodiment, a single three-port valve is controlled between the inlet and outlet pressures of the pump.

Abstract: A gas-contaminant separator includes inlet ports at the bottom of each leg of an inverted V-shaped housing and an outlet port at the top vertex. The total cross-sectional area of the inlet ports provide flow velocities below two meters per second and of the outlet port provides flow velocities below one and a half meters per second. First baffles are provided proximate the inlet ports to direct gas-contaminant mixtures towards and into a first contact with each other. Second baffles, disposed above the first contact zone cooperate with the housing to define a primary sedimentary precipitation zone and cause first retroversions of the mixtures towards and across the tops of the first baffles with the bulk of the contaminants being centrifugally precipitated by the first retroversions into the primary sedimentary precipitation zone for sedimentary precipitation to the bottoms of the housing.

Abstract: A gas-oil separator includes a bowl shaped housing open to the bottom for mounting to the rocker arm cover of an internal combustion engine. The housing and an encircling gasket at the bottom is secured to the rocker arm cover by a pair of bolts passing through the top of the housing and threaded to a clamp plate positioned inside of the rocker arm cover. First, second, and third baffles are secured to the clamp plate and sequentially spaced therefrom so as to be disposed within the housing. The clamp plate contains a pair of openings for the flow of mixed engine blow-by gases and oil, and a pair of holes for exit of the separated oil; the housing contains an outlet port proximate the top for the exhaust of the separated blow-by gases. The first baffle plate contains three openings which are completely out of line with the two openings in the clamp plate.