Control system for axial piston fluid energy translating device
AssigneeAbex Corporation
InventorsEllis H. Born, William H. Meisel, Alan H. Viles
Life of this patent
Estimating the term…
Abstract
A variable displacement axial piston pump has a rocker cam for controlling the output of the pump. The rocker cam is driven by a fluid motor member. A valve with a follow-up device regulates pressure fluid flow to the fluid motor member to move the rocker cam. Both the fluid motor member and a part of the follow-up device are rigidly secured to and movable with the rocker cam to provide precise positioning of the rocker cam.
Claims10
A control device for a fluid motor having a movable fluid motor member, comprising an input member for setting the desired position of said fluid motor, a valve shoe having a pressure fluid supply port and carried by said input member, a flat valve plate having a pair of fluid receiving ports, passage means for connecting both of said fluid receiving ports to said fluid motor, said input member being alternatively movable between a first position in which said fluid supply port is aligned with one of said fluid receiving ports to thereby move said movable fluid motor member in one direction, a second position in which said fluid supply port is aligned with the other of said fluid receiving ports to thereby move said movable fluid motor member in another direction and a null position in which said fluid supply port is misaligned with both of said fluid receiving ports and said fluid motor is inoperative, said valve plate being movable in direct response to movement of said movable fluid motor member to misalign said fluid receiving ports and said fluid supply port when said fluid motor reaches the position set by said input member, and differential area means on said valve shoe responsive to fluid pressure to move said shoe away from said valve plate a predetermined distance to permit limited fluid flow therebetween and thus create a hydrostatic bearing.
A control valve for controlling pressure fluid, comprising a flat valve plate having a pair of fluid receiving ports, an input member, a valve shoe having a fluid supply port carried by said input member and slidable on said valve plate, said input member alternatively movable between a first position in which said fluid supply port is aligned with one of said fluid receiving ports, a second position in which said fluid supply port is aligned with the other of said fluid receiving ports, and a null position in which said fluid supply port is misaligned with both of said fluid receiving ports, means biasing said valve shoe toward said valve plate, and self-modulating pressure responsive means opposing said biasing means to move said shoe away from said valve plate a predetermined distance to permit fluid flow therebetween and thus create a hydrostatic bearing said self-modulating pressure responsive means includes a plurality of fluid receiving pockets formed in said shoe adjacent said valve plate, means for supplying pressure fluid to each of said pockets including a fixed orifice, and variable outlet means automtically adjustable to regulate the pressure of the supply fluid in said pockets to move the shoe relative to the valve plate such that said predetermined distance is maintained.
A control valve for controlling pressure fluid, comprising a flat valve plate having a pair of fluid receiving ports, an input member, a valve shoe having a fluid supply port carried by said input member and slidable on said valve plate, said input member alternatively movable between a first position in which said fluid supply port is aligned with one of said fluid receiving ports, a second position in which said fluid supply port is aligned with the other of said fluid receiving ports, and a null position in which said fluid supply port is misaligned with both of said fluid receiving ports, means biasing said valve shoe toward said valve plate, and self modulating pressure responsive means opposing said biasing means to move said shoe away from said valve plate a predetermined distance to permit fluid flow therebetween and thus create a hydrostatic bearing, said biasing means comprises a first area on said shoe responsive to fluid pressure to create a first force biasing the shoe away from said plate and a second area on said shoe responsive to fluid pressure to create a second force biasing said shoe toward said plate, the sum of the first and second forces comprising a resultant force biasing said shoe toward the valve plate and said self-modulating pressure responsive means include a third area means, means restricting the flow of pressure fluid to said third area means, and variable outlet means from said third area means, said third area means being responsive to fluid pressure to create a third force to oppose said resultant force and move said shoe away from said valve plate until said third force equals said resultant force.
A control device for a fluid motor having a movable fluid motor member, comprising an input member for setting the desired position of said fluid motor, a flat valve plate having a pair of fluid receiving ports, a valve shoe mounted in a bore in the input member and positioned between the input member and the valve plate wherein the valve shoe is axially movable and tiltable in the bore to accommodate variations in parallelism and distance between the input member and the valve plate, a pressure fluid supply port opening into a flat surface in said valve shoe adjacent said valve plate, a source of pressure fluid, passage means for connecting both of said fluid receiving ports to said fluid motor, said input member being alternatively movable between a first position in which said fluid supply port is aligned with one of said fluid receiving ports to thereby move said movable fluid motor member in one direction, a second position in which said fluid supply port is aligned with the other of said fluid receiving ports to thereby move said movable fluid motor member in another direction and a null position in which said fluid supply port is misaligned with both of said fluid receiving ports and said fluid motor is inoperative, said valve plate being movable in direct response to movement of said movable fluid motor member to misalign said fluid receiving ports and said fluid supply port when said fluid motor reaches the position set by said input member, and differential area means on said valve shoe responsive to fluid pressure to move said shoe away from said valve plate a predetermined distance to permit limited fluid flow therebetween and hydrostatically balance the shoe.
A control device for a fluid motor having a movable fluid motor member, comprising an input member for setting the desired position of said fluid motor, means for pivotally attaching the input member to a housing, a manual control arm for pivoting the input member, a first valve shoe mounted in a bore in the input member between the input member and the housing, a flat surface on said first valve shoe adapted to slide on a flat surface on said housing, said first valve shoe adapted to move axially and tilt in said bore to accommodate variations in parallelism and distance between the input member and the housing, a first fluid supply port in said housing which opens into the flat surface of the housing adjacent the first valve shoe, a source of pressure fluid for said first fluid supply port, a second bore in the first valve shoe in fluid communication with said first fluid supply port, a flat valve plate having a pair of fluid receiving ports, a second valve shoe mounted in the bore in the input member and positioned between the input member and the valve plate, a second flat surface on said second valve shoe adapted to slide on said flat valve plate, said second valve shoe adapted to move axially and tilt in the first said bore to accommodate variations in parallelism and distance between said input member and said valve plate, a third bore in the second valve shoe in fluid communication with said second bore for receiving said pressure fluid, a second pressure fluid supply port opening into said second flat surface in said second valve shoe adjacent said valve plate, passage means for connecting both of said fluid receiving ports in the valve plate to said fluid motor, said input member being alternatively movable between a first position in which said second pressure fluid supply port is aligned with one of said fluid receiving ports to thereby move said movable fluid motor member in one direction, a second position in which said second pressure fluid supply port is aligned with the other of said fluid receiving ports to thereby move said movable fluid motor member in another direction and a null position in which said second pressure fluid supply port is misaligned with both of said fluid receiving ports and said fluid motor is inoperative, said valve plate being movable in direct response to movement of said movable fluid motor member to misalign said fluid receiving ports and said second pressure fluid supply when said fluid motor reaches the position set by said input member, and differential area means on said second valve shoe responsive to fluid pressure to move said second shoe away from said valve plate a predetermined distance to permit limited fluid flow therebetween and hydrostatically balance the shoe.
Dependencies are inferred from the claim text.