Abstract: A preassembled carburetor valve of the general type shown and described in U.S. Pat. No. 3,454,036 has a floating disc-type valve without an encircling metal rim. The hollow body is provided with oppositely disposed "cathedral window" openings. The valve body, including the valve seat and the cathedral windows, is die cast.

Abstract: A test fixture for EGR valves has a support with a flat upper surface with a well opening through it spaced from the boundaries of the upper surface. A conduit, open at two ends, communicates with the atmosphere at one end and with the well intermediate its ends. A venturi tube communicates with the other end of the conduit. The venturi tube has a throat portion and an aspirating line communicating at one end with the throat portion of the venturi tube and at the other with a vacuum fitting for connection to the vacuum fitting of an EGR valve resting on the flat upper surface of the fixture. A pressure fitting is connected to the venturi tube to accommodate a complementary fitting from a source of gas under pressure. The venturi tube and conduit are dimensioned and arranged to deliver a vacuum to the vacuum fitting and a pressure to the well of a magnitude at which the EGR valve will operate normally if the EGR valve is in operating condition.

Abstract: A fuel efficiency display device, in the form of an intake manifold suction measuring and display intended to be mounted within the passenger compartment of an internal combustion engine propelled vehicle, includes an elongated housing with a hollow open bottomed outer shell with a mounting boss extending lengthwise of it, a central, open ended sleeve with a cylindrical bore, the sleeve being spaced from and connected to an inside wall of the shell by spiders and a sight tube, fitting within the sleeve, through which an indicator spool slides. The sight tube has an annular shoulder which abuts the upper end of the sleeve.

Abstract: A power assist remotely controlled servo controller for proportionally controlling the operation of a directional control valve, the controller including a servo-controlled force amplifying piston assembly to operate the directional control valve and a pilot pressure balanced piston connected to the servo-controlled piston assembly to control the directional control valve. The balanced pilot pressure forces acting on the pressure balanced piston being controlled by either a hydraulic or electric controller from a remote location.

Abstract: An open center type control valve for a hydraulic motor, wherein pressure fluid from a source is caused to flow from the valve inlet to a motor port at a substantially uniformly metered rate despite fluctuations in the load on the governed fluid motor, due to the operation of a flow control mechanism which regulates bypass of excess fluid through the open center passage to the valve outlet in accordance with variations in the pressure differential between the inlet and outlet end portions of the open center passage.

Abstract: A pressure compensating valve spool assembly for a hydraulic flow control valve the spool assembly being slidably positioned in the central bore of a valve housing for movement from a neutral position wherein fluid will flow through the valve assembly to reservoir to operative positions in either direction to provide fluid communication between fluid inlet passages to one of a pair of cylinder passages in the valve housing, the other of said cylinder passages being connected to one of the pair of reservoir passages. The valve spool assembly includes a symmetrical valve spool having valve members at each end which are responsive to variations in the pressure relation between inlet pressure and cylinder pressure to control the fluid flow rate to the cylinder passage. Any excess flow is bypassed to reservoir at minimum pressure loss.

Abstract: A proportional pressure compensating hydraulic control valve having a valve body and a valve spool mounted in the valve body for movement from a neutral or open center position wherein fluid flows through the valve body to an operating position wherein the flow of fluid through the valve is restricted to direct inlet fluid through a flow control orifice to a pressure passage within the valve body, the pressure passage being connected to one of a pair of cylinder passages, the other cylinder passage being connected to a tank passage. The valve spool in an open center mode controlling the flow of fluid to the control orifice and being pressure compensated to maintain a predetermined flow rate through the control orifice, pressure compensation being achieved by imposing inlet and pressure passage pressures selectively to each end of the valve spool so that the valve spool responds to the pressure differential across the control orifice.

Abstract: A pressure compensating valve spool for a hydraulic flow control valve, the valve spool being slidably positioned in the valve for movement from a neutral position wherein fluid will flow through the valve to operative positions in either direction to provide fluid communication from a fluid inlet passage to one of a pair of cylinder passages, the other of said cylinder passages being in fluid communication with a tank passage. The valve spool includes fluid pressure compensating members positioned within each end of the valve spool to vary the fluid flow rate to the cylinder passages, the fluid flow rate being varied to maintain a constant pressure differential between the pressure in the fluid inlet passage and the pressure of the fluid in the valve spool.

Abstract: A pilot operated check valve having pressure actuated poppet valves positioned to limit flow in one direction through each of two flow paths through the valve, each poppet valve including a one-way check valve to control reverse flow through the two flow paths and a spool positioned in said valve and being responsive to inlet pressure in one or the other of the flow paths to open the check valve in the opposite fluid flow path when the pressure differential between inlet pressure and return pressure is within a predetermined ratio.