Abstract: A capacity control circuit for a fluid displacement apparatus, especially for a rotary vane compressor, which circuit controls the volume of fluid displaced or transmitted through such apparatus. The present invention provides a means to retain the vanes within the rotor guide slits with a fluid pressure differential to modulate the volume throughput of such rotary vane compressor or apparatus. This vane control is provided by controlling the suction or input pressure to such apparatus through a fluid control valve.

Abstract: A hydraulic motor comprises vanes slidable axially in lodgings of a rotor against a continuous stator bottom surface. The motor works with a hydrostatic transmission of power applied to rolling stock. The bottom surface has recesses formed therein on movable elements of stator wherein a constant pilot pressure is fed to said movable elements and the motor is a self regulated variable capacity motor since the capacity thereof results from the depth of the recesses due to the opposition of two forces, one from the pilot pressure and the other from a pressure coming from the resisting torque.

Abstract: A gerotor pump or rotary fluid power transmission having a displacement control device for changing the volume of fluid delivered. The displacement control device operates by changing the eccentric position between the inner and outer rotors. The inlet and outlet ports of the pump are kept separate to maintain a unidirectional flow from the inlet to the outlet port across open mesh crossover zone. The closed mesh crossover zone is moved relative to the open mesh crossover zone and maintains separation between the inlet and outlet ports. As the eccentric position of the outer rotor relative to the inner rotor is changed, the volume of fluid transferred from the inlet port to the outlet port over the open mesh crossover zone is varied between a minimum and maximum amount. In one embodiment, the displacement control device is manually shifted.

Abstract: A variable displacement vane type hydraulic pump of simple construction automatically varies its output flow rate, between a maximum value and zero, in response to changes in the output pressure. The pump is characterized by a laterally shifting flow modulating member located in a central recess of a vane carrying rotor and whose lateral position is dictated by the pressure existing at the outlet port. The pump can run continuously at a no-flow condition without overheating or stalling and its rotor direction may be reversed by merely reversing the functions of its two ports.

Abstract: A control ring in sliding contact with the radially outer ends of fluid displacing vanes on a pump rotor, is angularly adjustable about a pivot formation in a pump housing on one radial side of the rotor opposite a limited sealing surface on the housing having a center of curvature on the rotor axis. A sealing element pivotally mounted on the control ring is biased into wiping contact with the sealing surface to divide the pump housing into inlet and outlet pressure chambers.

Abstract: A control device for a positionable pump has a body with inner and outer diameters eccentric to each other mounted in the pump housing bore and is actuated by hydraulic pressure in one angular direction. An opposing spring force acts in the opposite direction for controlling the angular position of the body. A controlled member is nested in the inside diameter of the body and a power rotated control member is nested within and drivingly engages the controlled member and is eccentric thereto, being a pair of pumping elements. The pump elements being gerotor or vane type elements utilized to pump fluids and which depend upon the eccentric position of their relative components for a fixed delivery of fluids. The body is controlled in infinitely angular positions relative to the pump housing to regulate the eccentric position of such pumping elements and thereby controlling the volume output of said pump elements relative to the demand of the external system increasing and diminishing needs.

Abstract: A variable displacement vane pump is provided in which a pair of rings having oval-shaped inner contours are rotatably mounted in side-by-side relationship. The rings are adapted for relative rotation to each other from a first position wherein the inner contours are in register with each other and a moved position wherein the inner contours are out-of-register, and means are provided for effecting the relative rotation, which include a gear system operatively connected to the rings. A rotor member is mounted for rotation within the rings and is formed with a plurality of circumferentially spaced recesses which extend the entire axial length of the rotor. Each of the recesses carries a pair of vanes in abutting relationship. The vanes are mounted for radial movement in the recesses and are adapted for slidable contact with the inner contours of the rings. The vanes form two side-by-side rows of vanes with each row in tracking relationship with the inner contours of the rings.

Abstract: A vane-type variable displacement pump is controlled by a first stage servo-valve. The servo-valve is controlled by a second stage which may optionally include devices which provide any of several desired control effects.

Abstract: A variable displacement vane type pump having a pivotally mounted ring member controllable to vary the eccentricity between the rotor and the ring thus controlling the pump displacement. The ring is positioned on the pivot such that the center thereof is always located in one quadrant relative to axes through the pivot point and the center of the pump rotor to continually maintain the net ring reaction force, due to internal pressure, directed to one side of the pivot connection in opposition to the displacement control pressure, which is impressed on a portion of the outer surface of the ring, whereby control stability throughout the displacement range is improved.

Abstract: The casing of a pump defines a threaded hole into which is inserted an outer block for reacting radially directed forces transmitted by a second inner block from a movable, pressurized cam ring surrounding the pump rotor. The blocks have mutually parallel mating surfaces arranged generally tangential to the ring. Onto one of such surfaces is bonded an anti-friction bearing material, such as a woven fabric or metal, to facilitate sliding action between them. The eccentric position of the cam ring is partly established by the action of system pressure acting on control pistons while the guided motion of the inner block further positions the ring to optimal adjustments made to the outer block.

Abstract: An adjustable volume vane-type rotary pump is disclosed in which volume control is obtained by adjusting the eccentricity of a control ring against which the vanes run. The control ring is urged towards its position of maximum eccentricity by a spring and position control of the ring is obtained by a piston and cylinder system operating in opposition to the spring. Operation of the piston and cylinder assembly is dependent on the dynamic pressure of fluid delivered by the pump so that when a certain speed of rotation is achieved the pressure exerted by the piston and cylinder system will be sufficient to overcome the force of the spring and adjust the position of the control ring.

Abstract: The casing of a pump defines a threaded hole into which is inserted an outer block for reacting radially directed forces transmitted by a second inner block from a movable, pressurized cam ring surrounding the pump rotor. The blocks have mutually parallel mating surfaces arranged generally parallel to a plane tangential to the ring. Onto one of such surfaces is bonded an anti-friction bearing material, such as a woven fabric or metal, to facilitate sliding action between them. The eccentric position of the cam ring is partly established by the action of system pressure acting on control pistons while the guided motion of the inner block further positions the ring to optimal adjustments made to the outer block.

Abstract: An internal-external gear pump wherein the fluid displacement thereof is variable. The internal gear is rotatably driven by a drive shaft about a fixed axis and the external gear is rotatably driven by the internal gear about a controlled movable axis eccentric to the fixed axis. Movement of the external gear axis causes the eccentricity between the internal and external gear axes to vary, thereby resulting in a change in the depth of gear tooth mesh such that the volume of fluid displaced by the meshing teeth is varied. The position of the external gear axis is established by a control ring which rotatably supports the external gear, and is mounted in a stationary housing so as to be rotatably positionable within arcuate limits about a fixed axis eccentric to both the axes of the internal and external gears.

Abstract: A variable-output pump has an output-adjusting element which is acted upon by a differential piston arrangement having oppositely facing active surfaces of a smaller and of a larger active area. Control fluid is permanently admitted to the smaller active area of the differential piston arrangement to act on the same and urge the output-adjusting element of the pump toward a low-output position. A biasing spring acts against the force of the fluid acting on the smaller surface, and the control fluid is also selectively admitted to the larger surface to urge the adjusting element toward higher outputs. A control slide controls the admission of the control fluid to the larger surface of the differential piston arrangement and has a housing provided with a bore in which a slide is mounted for movement longitudinally of the bore. The slide has an end face acted upon by the control fluid and another end face acted upon by a spring.