Devices and method include relatively moving elements having one or more bearing surfaces defining a gap between the elements into which a fluid is received. At least one of the bearing surfaces comprises a varying topography to provide pressurized volumes of the fluid in order to define a hydraulic bearing to support at least one of the elements during movement.

A throttle unit is equipped with a grooved block including at least one minute groove formed on a plane surface, and an opposite block having a plane surface which is opposite to the minute groove. The grooved block and the opposite block are detachably joined so as to be opposite to each other. A throttle fluid path is formed by the minute groove and the plane surface of the opposite block. At least one surface of each of the minute groove is constituted by a curved surface or an inclined surface that is inclined with respect to the plane surface of the grooved block.

The method comprises depositing a coating of metal material on the inside surface of the body (4) of the stator (36), impregnating said coating with a self-lubricating composite material (20), machining internal cells (28) in the thickness of the coating (10), and machining orifices (34) leading into the cells.

A lubricant supported electric motor includes a stator presenting an stator raceway, and a rotor movable relative to the stator and presenting a rotor raceway disposed in spaced relationship with the stator raceway to define a gap therebetween. A lubricant is disposed in the gap for supporting the rotor relative to the stator. The stator defines at least one hydrostatic support chamber disposed in radially recessed relationship relative to the stator raceway and in fluid communication with the gap. The stator also defines a passageway disposed in fluid communication with the at least one hydrostatic support chamber for providing lubricant to the at least one hydrostatic support chamber and the gap. A flow restriction mechanism is disposed in fluid communication with the passageway for controlling and balancing a supply and pressure of the lubricant in the hydrostatic support chamber.

A hydrostatic bearing spindle device includes: a spindle includes tapered portion having tapered radial receiving surface and flange having first thrust receiving surface and second thrust receiving surface formed at rear side from first thrust receiving surface; first thrust bearing has first thrust bearing surface facing first thrust receiving surface; second thrust bearing has second thrust bearing surface facing second thrust receiving surface; radial bearing facing tapered radial receiving surface; rotation regulator regulates relative rotation of one of first thrust bearing and second thrust bearing with respect to the other; and housing has first screw groove which is screwed with first thrust bearing and second screw groove which is screwed with second thrust bearing. Second screw groove has larger screw pitch than first screw groove does when tapered portion expands rearward, and first screw groove has larger screw pitch than second screw groove does when tapered portion expands frontward.

A hydrostatic bearing spindle device includes: a spindle includes tapered portion having tapered radial receiving surface and flange having first thrust receiving surface and second thrust receiving surface formed at rear side from first thrust receiving surface; first thrust bearing has first thrust bearing surface facing first thrust receiving surface; second thrust bearing has second thrust bearing surface facing second thrust receiving surface; radial bearing facing tapered radial receiving surface; rotation regulator regulates relative rotation of one of first thrust bearing and second thrust bearing with respect to the other; and housing has first screw groove which is screwed with first thrust bearing and second screw groove which is screwed with second thrust bearing. Second screw groove has larger screw pitch than first screw groove does when tapered portion expands rearward, and first screw groove has larger screw pitch than second screw groove does when tapered portion expands frontward.

A control system of a machine tool includes a hydraulic pressure adjuster. The hydraulic pressure adjuster includes a sequence program controller that includes components for adding a function of adjusting a hydrostatic pressure of a static pressure oil supplied to a hydrostatic pressure guide mechanism, which are a pressure setting unit, a constant acceleration motion controller, a workpiece-weight calculator and a supply state adjuster.

A throttle unit is equipped with a grooved block including at least one minute groove formed on a plane surface, and an opposite block having a plane surface which is opposite to the minute groove. The grooved block and the opposite block are detachably joined so as to be opposite to each other. A throttle fluid path is formed by the minute groove and the plane surface of the opposite block. At least one surface of each of the minute groove is constituted by a curved surface or an inclined surface that is inclined with respect to the plane surface of the grooved block.

A noncontact fluid bearing is manufactured by disposing a flow controller in a cavity of a carrier to form a pressure chamber within the cavity. A sealing layer of the flow controller is located between a porous layer of the flow controller and the pressure chamber and has micro through holes communicating with the pressure chamber and pores of the porous layer. Because the sealing layer is located in the pressure chamber and a surface of the porous layer is exposed by a housing of the carrier, the noncontact fluid bearing can be processed from the exposed surface of the porous layer to conform standards of thickness and flatness. Furthermore, the sealing layer peeling from the noncontact fluid bearing is prevented.

A system includes a hydraulic transfer system configured to exchange pressures between a first fluid and a second fluid, where the first fluid has a pressure higher than the second fluid, includes a sleeve comprising an elliptical shape, a cylindrical rotor disposed within the sleeve in a concentric arrangement, where the cylindrical rotor is configured to rotate circumferentially about a rotational axis and has a first end face and a second end face disposed opposite each other. The system includes a first and second end cover having a first and second surface which interface with a first and second end face of the rotor. The system includes a first and a second radial clearance disposed between the sleeve and the cylindrical rotor, where the radial clearances are configured to increase or decrease based at least in part on a pressure differential.