Abstract: A helically continuous projection 1a is formed around a sliding surface 1A of a sliding bearing 1 at a given pitch p. The surface roughness h of the sliding surface 1A, including the projection 1a, is chosen to be equal to or less than one-half the height H of the projection. This provides a sliding bearing 1 which exhibits an improved running-in performance.

Abstract: A dynamic pressure bearing device for use in a motor including a shaft and a frame. Two bearings interconnect the shaft and the frame of the motor. The two bearings contain a noncompressible fluid. A mechanism for minimizing axial vibrational movement of the shaft is part of the bearing device. In one arrangement, the mechanism is a device connected to the shaft, such that a narrow gap is defined between an end of the device and the frame to provide a flow resistance to the noncompressible fluid. The device connected to the shaft maintains a decreasing width to minimize a loss of torque in the motor.

Abstract: Provided is a dynamic pressure gas bearing structure which is applicable to a high-speed rotation driving part such as a hard disk driver or the like and has high rotational accuracy in high-speed rotation. The dynamic pressure gas bearing structure comprises a shaft body and a bearing body. When the shaft body and the bearing body are so arranged that central axes thereof are aligned with each other, a substantially cylindrical gap is defined between the outer peripheral surface of the shaft body and the inner peripheral surface of the bearing body. The gap has at least one gap change portion whose thickness is changed with respect to a central angle corresponding to the circumference along the outer peripheral surface of the shaft body. The gap change rate .alpha. is at least 1.0.times.10.sup.-4 /.degree. and less than 10.0.times.10.sup.-4 /.degree. .

Abstract: A polygon scanner has a lighter rotating shaft on which a polygon mirror is mounted, to prevent a positional deviation of the polygon mirror from the rotating shaft in high speed rotation, in which the rotating shaft is supported through a dynamic pressure air bearing on a fixed shaft, in which the polygon mirror and motor constituent members are mounted on the rotating shaft, and in which the rotating shaft and the polygon mirror are made of respective light weight materials matched with each other in coefficient of thermal expansion, for example of aluminum or an aluminum alloy. Further, an anodic oxide film is formed at least on a portion where the rotating shaft could contact with the fixed shaft, and floating means is provided for constantly floating the rotating shaft relative to the fixed shaft upward in an axial direction thereof.

Abstract: A planet bearing and gear assembly for the carrier of a speed increasing planetary gear train for driving a diesel engine turbocharger or the like includes an enlarged diameter gear bore and associated bearing outer diameter for lightening the gear and increasing the bearing area to at least 50 percent and preferably more than 65 percent greater than those of the bearing inner wall and the outer diameter of an associated support pin. Self-cleaning of unfiltered dirt particles in the engine lubricating oil is provided by dirt expulsion passages formed by flats at the edges of an oil supply groove in the planet bearing while operation with entrained dirt particles capable of passing through the engine lubricating oil filters is improved by increased oil film thickness resulting from reduced bearing loads due to reduction of mass of the planet gears and increased bearing surface.

Abstract: A hydrostatic/hydrodynamic flywheel for a press including a flywheel mounted for rotation about a non-rotating quill. A bronze bushing is disposed between the quill and flywheel. Hydrostatic pad areas are located on the quill opposite the bushing. These pad areas are flooded with pressurized oil or liquid to create a hydrostatic bearing area. During operation, flywheel and bearing rotation cause a hydrodynamic bearing effect to occur. The hydrostatic/hydrodynamic bearing eliminates the need for conventional anti-friction roller or ball bearings, provides indefinitely long life with full-film lubrication, high shock load capacity, high vibration damping, and a high value of radial and tipping stiffness.

Abstract: Disclosed is the improvement in a dynamic air pressure bearing in which a rotor is supported at high speed in the non-contact state. In an optical deflector, a stationary shaft is planted at the center portion of a housing. A stator core is disposed on a stud. A magnet yoke is integrated with a sleeve rotated relative to the stationary shaft. The magnet yoke contains an inner magnet and an outer magnet. A rotary polygonal mirror is mounted on a flange fixed on the sleeve by means of a center screw and a mirror cap. The rotary polygonal mirror is rotated at high speed together with the sleeve relative to the stationary shaft, thus constituting a dynamic air pressure bearing between the shaft and the sleeve. The stationary shaft is constituted of a main body and a ring-like bearing member fitted in the main body. The bearing member is formed of a ceramic material and formed with grooves for generating dynamic air pressure. The sleeve is preferably constituted of a main body and a bearing member of ceramic.

Abstract: A pneumatic and magnetic bearing type motor provides a hollow rotary member fitted rotatably on a stationary shaft, radial pneumatic bearings having dynamic pressure generating grooves formed on one of the stationary shaft and hollow rotary member, supporting the hollow rotary member in a radial direction with the aid of dynamic pressures generated, and a thrust magnetic bearing supporting the hollow rotary member in a thrust direction thereof. In the motor, the position where the hollow rotary member is supported by the thrust magnetic bearing is substantially coincident with the equilibrium point where moments of the pressures are equal, whereby the motor is substantially free from vibration during operation, and the bearings are substantially prevented from being damaged when the motor is started or stopped.

Abstract: A spindle system is comprised or a journal and thrust air bearing. The journal bearing; has two sets of opposing groove areas. The thrust air bearing has two sets of spiral grooves. The thrust air bearing is gimballed to compensate for misaligment. A bias contact member is connected to the rotating member along the axis of rotation and provides electrical grounding, The spindle system is especially applicable to mounting recording disks in a data storage disk drive.

Abstract: An electric motor construction includes a rotor housing and sleeve which surrounds a shaft/thrust plate. The thrust plate is enclosed in a dead end cavity and is surrounded by a fluid which forms a fluid bearing. The shaft has asymmetrical grooves which create a net pressure gradient from a capillary seal formed near the bottom of the shaft toward the dead end cavity. This helps maintain the capillary seal and reduce the risk of cavitation.

Abstract: In a dynamic pressure bearing having a sleeve and a shaft fitted in the sleeve, dynamic pressure generating grooves are formed on an outer cylindrical surface of the shaft. The dynamic pressure generating grooves consist of first oblique grooves disposed in a first cylindrical zone of the outer cylindrical surface, second oblique grooves disposed in a second cylindrical zone spaced from the first cylindrical zone in an axial direction, and cross grooves (or generally X-shaped grooves) disposed in an intermediate cylindrical zone between the first and second cylindrical zones. The first oblique grooves are oblique in a direction with respect to a generating line of the cylindrical surface and the second oblique grooves are oblique in a direction opposite to the direction in which the first oblique grooves are oblique.

Abstract: A hydrodynamic bearing device incorporates a relatively rotatable shaft 1 and a sleeve 2 internally sealed with the shaft 1. A groove for generating dynamic pressure is formed on an external circumferential surface of the shaft 1 or on internal circumferential surface of the sleeve 2. A circumferential groove 1a is formed at one end of the shaft 1 external to the bearing. An annular sealing plate 3 is secured to the sleeve 2 and interegagging with the shaft 1 external to the bearing and the circumferential groove 1a. A labyrinth is formed between the inner-diametric domain of the sealing plate 3. An annular recessed domain 2c is defined by internal circumferential surface of the sleeve 2 and the sealing plate 3 at a position substantially opposite the circumferential groove 1a. An oil-pooling space 4 thereby formed by the shaft 1, the circumferential groove 1a, the sleeve 2, the sealing plate 3, and the annular recessed domain 2c.

Abstract: A hydrodynamic bearing for limited roller oscillation incorporates a pair of oil slots which clear debris from the roller/pin interface and provide oil to readily lubricate the entire load bearing surface of a pin. The preferred oil slots each extend lengthwise along the pin, and widthwise generally across respective chords of the pin circumference. The oil slots are positioned in spaced relationship such that their respective chords define an angle whose vertex is beyond the circumference of the pin, and their spacing defines an upper load bearing zone along a portion of the circumference of the pin, and opposite therefrom, a larger, lower load bearing zone defined along another portion of the circumference of the pin.

Abstract: A hydrodynamic gas bearing includes a cantilevered shaft having a free end, a fixed end, and a communicating hole for communicating with a passage formed at an end surface of the free end of the shaft. A cover member is rotatably arranged around the shaft to cover a periphery of the shaft. One of an inner surface of the cover member which faces the fixed end of the shaft and an outer surface of the fixed end of the shaft having a herringbone-configured hydrodynamic pressure generating grooves for preventing gas from being fed from a fixed end side to a free end side of the shaft. One of the inner surface of the cover member which faces the free end of the shaft and an outer surface of the free end of the shaft has helical-configured hydrodynamic pressure generating grooves for feeding gas from the free end side to the fixed end side of the shaft.

Abstract: A spindle system is comprised of a journal and thrust air bearing. The journal bearing has two sets of opposing groove areas. The thrust air bearing has two sets of spiral grooves. The thrust air bearing is gimballed to compensate for misalignment. A bias contact member is connected to the rotating member along the axis of rotation and provides electrical grounding. The spindle system is especially applicable to mounting recording disks in a data storage disk drive.

Abstract: A radial sliding-contact bearing for rotary rolls has a cylindric fixed inner portion (2), a sleeve (4) rotatable thereon, and a gap (6) between the sleeve and the inner portion intended for a water film which in operation forms a rotary bearing for the sleeve. On its peripheral surface the inner portion has recesses (8') for facilitating an even distribution of the water over the surface of the inner portion (2) in operation. The water is fed to the gap (6) through first and second longitudinal rows of nozzle openings (14, 16) in the peripheral surface of the inner portion (2), which are connected to a common water supply channel (18) in the inner of the inner portion.

Abstract: A hydrodynamic gas bearing includes a cantilevered shaft having a free end, a fixed end, and a communicating hole for communicating with a passage formed at an end surface of the free end of the shaft. A cover member is rotatably arranged around the shaft to cover a periphery of the shaft. One of an inner surface of the cover member which faces the fixed end of the shaft and an outer surface of the fixed end of the shaft has herringbone-configured hydrodynamic pressure generating grooves for preventing gas from being fed from a fixed end side to a free end side of the shaft. One of the inner surface of the cover member which faces the free end of the shaft and an outer surface of the free end of the shaft has helical-configured hydrodynamic pressure generating grooves for feeding gas from the free end side to the fixed end side of the shaft.

Abstract: A gas supported bearing includes a first stationary bearing element having a longitudinal axis and a first bearing surface. A second rotating bearing element is coaxially aligned with respect to the first bearing element and includes a second bearing surface. A pneumatic load ramp is formed in one of the bearing surfaces to apply an asymmetric load to either bearing element to eliminate bearing whirl instability.

Abstract: A dynamic pressure bearing device has a bearing and a shaft which is partly accommodated in the bearing. A sliding surface of the bearing is provided with dynamic pressure grooves of circular shape. When the direction of relative movement between the shaft and the bearing is reversed, fluid within the dynamic pressure grooves can move its flowing direction change along the circular dynamic pressure grooves. Further, the dynamic pressure grooves, being of circular shape, can generate dynamic pressures of equal levels irrespective of the direction of the movement.

Abstract: A pump integral with an electric motor has an integral rotor and impeller assembly that rotates within a stator casing and is supported on hydrostatic radial and thrust bearings. The pump avoids having to provide external seals or friction type bearings. The unit has a stator with windings therein contained within a pump casing which has an axial liquid entry and a liquid outlet. An integral rotor and impeller assembly is mounted for rotation on a fixed axial shaft within the stator. The integral rotor and impeller assembly is positioned axially relative to the stator casing by hydrostatic thrust bearings where the pressure for the thrust bearing fluid is generated by radial ducts located within the integral rotor and impeller assembly.

Abstract: A gas supported bearing includes a first stationary bearing element having a longitudinal axis and a first bearing surface. A second rotating bearing element is coaxially aligned with respect to the first bearing element and includes a second bearing surface. A pneumatic load ramp is formed in one of the bearing surfaces to apply an asymmetric load to either bearing element to eliminate bearing whirl instability.

Abstract: An electric motor, in which the thrust bearing action is performed by the magnetic attraction forces induced between a annular stator core with toroidal coils and magnets confronting the stator core, includes at least a cup-shaped member with a central cylindrical portion opened at the center, the cup-shaped member serving as a magnet yoke and a seat on which an element to be driven by the motor is mounted, and a cylindrical rotary sleeve press-fitted in the central cylindrical portion. This construction contributes to a reduction of the weight, size and manufacturing cost of the motor.

Abstract: An optical deflector of an air bearing type has a fixed shaft; a rotary shaft having a hollow portion fitted onto the fixed shaft; a support device disposed between an end portion of the fixed shaft and an end portion of the hollow portion opposite thereto and supporting the rotary shaft in an axial direction thereof; a radial air bearing formed between an inner circumferential face of the hollow portion and an outer circumferential face of the fixed shaft; a polygon mirror fixed to the rotary shaft; a driving device for rotating the rotary shaft; a device for deflecting light irradiated onto the polygon mirror by rotating the rotary shaft through the driving device; a device for forming a flange for fixing the polygon mirror thereto integrally with the rotary shaft; and a device for setting an upper end portion of the support device on a fixed shaft side thereof to be lower than an upper end face of the polygon mirror.

Abstract: A laying roller for textile yarns which, via a central air supply, supplies two air feed channels which are separated from each other. Each channel feeds air via a respective one of two porous sintered bearing bushings which are axially separated from each other. The air passing through the porous bushings builds up an air cushion for supporting a surrounding roller shell.

Abstract: A dynamic pressure bearing device induced a housing having a sleeve and a thrust receiver and a shaft fit into the sleeve. Herringbone-shaped grooves for generating dynamic pressure comprising outer groove segments and inner group segments are disposed to at least one of the inner cylindrical surface of the sleeve and the outer cylindrical surface of the shaft at two axially spaced apart positions. The axial length of the outer groove segment is longer than that of the inner groove segment, and the difference of the axial length for the outer and the inner groove segments is greater in the lower herringbone-shaped grooves than in the upper herringbone-shaped grooves.

Abstract: A rotor shaft provided with a fan is rotatably supported by pneumatic bearings for the purpose of high speed rotation with low noise. The rotor shaft provided with the fan can also be supported at one end by a resilient bearing so as to provide high speed rotation even if the concentricity of the bearings is low.

Abstract: A piston for a gas-operated linear actuator wherein a double-acting piston moves axially within a cylinder in response to gas pressure applied intermittently to chambers on either side of the piston. The piston has reservoirs in the form of holes in each of its faces and a pair of spaced-apart circumferential grooves, one communicating with the holes in one piston face and the other with the holes in the other piston face, the two sets of grooves and holes being kept out of communcation with one another. Gas under pressure introduced into one chamber forces the piston to move toward the opposite chamber, and a portion of the gas passes into the holes and out through the adjacent groove, providing a stream of gas between piston and cylinder walls, producing a gas-bearing effect.

Abstract: A piston engine having a reciprocating piston, which is journalled in a radial direction with respect to the direction of translation by means of at least one dynamic groove bearing located within the piston and is separated from a compression space by an annular sealing gap at an outer surface of the piston. The piston engine is suitable for use in compressors and cryo-coolers, more particularly for cooling of computer processors.

Abstract: A dynamic pressure-type fluid bearing usable in a polygon mirror scanner for a laser beam printer includes a sleeve having an inner peripheral surface and a bottom face, and a journal having an outer peripheral surface cooperating with the inner peripheral surface of the sleeve across a predetermined clearance, and an end face cooperating with the bottom face of the sleeve. In an embodiment, the sleeve is rotatable relative to the journal and is held by a magnetic retaining force in such a manner that a predetermined gap is formed between the bottom face of the sleeve and the end face of the journal even when the bearing is at rest. The bottom face of the sleeve includes a porous body so that the gap between the bottom face and end is communicated with the outside of the bearing.

Abstract: A gas bearing including a support having a longitudinally extending cylindrical bore, of a predetermined diameter and an elongated generally cylindrical shaft rotatable within the bore of the shaft being of a predetermined diameter less than the diameter of the bore in the support. The outer surface of the shaft is uniquely provided with a plurality of circumferentially spaced, longitudinally extending recesses of a predetermined depth, each of which defines an elongated, generally radially outwardly extending step of a predetermined height. The outer surface of the shaft is also provided with a plurality of circumferentially spaced, longitudinally extending grooves of a predetermined depth disposed proximate the steps.

Abstract: A single-ended turbomolecular vacuum pump operable in the free molecular flow pressure range having an improved bearing assembly located between the motor and the pump rotor discs is disclosed. The improved bearing assembly which is of the "plain" or "sleeve" liquid lubricated type with the bearing surfaces has a relatively high ratio of journal diameter to bearing axial length and includes lubricant ports radially disposed about both the centers of the bearing and the journal. The improved bearing assembly is characterized by improved heat transmission capabilities, high tolerance for misalignment, long life and significant reduction of pump vibration.

Abstract: A dynamic pressure air bearing which comprises a sleeve member, with a shaft member arranged coaxially therein. Air is introduced through a clearance between the sleeve member and the shaft member by the rotation of either the sleeve member or the shaft member, and the dynamic pressure of the air acts on the inner surface of the sleeve member and the surface of the shaft member. Ceramics cover at least one of the inner surface of the sleeve member and the surface of the shaft member. The ceramics include at least one type selected from among SiN, SiCN, SiC, SiO, TiN, TiC, TiCN, BN, BC, BCN, Al.sub.2 O.sub.3, WC, and diamond.

Abstract: The invention relates to a gas bearing with a bearing surface arranged on a gas permeable element to which a pressure medium can be supplied from an external source. The bearing surface is arranged on a less permeable surface layer, through which holes are made. In order to ensure good gas flow through the holes, the holes extend into the porous material a distance corresponding to at least half the diameter of the holes, and those portions of the holes which are situated inside said surface layer are limited by porous material.

Abstract: The invention disclosed herein relates to an inherent variable fluid restrictor for regulating fluid pressure in a hydrostatic bearing. The inherent variable fluid restrictor is comprised of a restrictor land surrounding a fluid supply port, a collection gallery around the restrictor land and containing a fluid cross-feed port, an isolation land around the collection gallery, and a bearing pocket around the isolation land. A flow channel connects the fluid cross-feed port to a diametrically opposed bearing pocket.

Abstract: A radial bearing comprising a cylindrical bearing member and a shaft arranged therein, the member and the shaft being rotatable with respect to each other and one of the cooperating bearing surfaces of the member and the shaft being provided with a pattern of shallow lubricant-pumping grooves which, during relative rotation between the member and the shaft, build up a pressure in a lubricant present between the shaft and the member. In one axial zone of the member or the shaft the relevant bearing surface is provided along one half of its circumference with a groove pattern which is arranged to pump in one circumferential direction, and along the other half of its circumference with an identical groove pattern which is arranged to pump in the opposite circumferential direction.

Abstract: A vibration-controlling bearing for controlling vibration developing in a rotary shaft supported in a housing of a rotary machine including a bearing member of a cylindrical shape interposed between an outer peripheral surface of the rotary shaft and an inner peripheral surface of the housing and spaced apart therefrom by respective gaps. A dynamic pressure is generated between an inner peripheral surface of the bearing member and the outer peripheral surface of the rotary shaft. Communicating ducts are formed in the bearing member for transmitting a portion of the dynamic pressure generated to a gap between the outer peripheral surface of the bearing member and the inner peripheral surface of the housing.

Abstract: A bearing system comprises two hydrodynamic bearings 5 and 7 by means of which two bodies 1 and 3 are rotatably supported relative to one another. Each of the bearings 5 and 7 has an inner and an outer pattern of helical grooves, which patterns in the direction of rotation for which the bearing system is intended build-up in opposite direction a pressure in lubricant. A reservoir 17 is situated between the bearings 5 and 7 and has two patterns 27 and 29 of feed grooves which pump lubricant towards the bearings 5 and 7 during operation.

Abstract: In an electric motor unit, a spindle is rotatably supported by bearing sections of a dynamic-pressure type, and is floated along its axis by a magnetic thrust bearing. At the bearing sections, air current layers are formed in the gaps between journals of the spindle and bearings by elongated parallel grooves formed along the axis, and the spindle is supported by pressure distributed over the air current layers. In the thrust bearing, rotor magnets fixed to the spindle are attracted to stator magnets fixed to the housing and surrounding the rotor magnets. The spindle is floated along the axis by the attraction between the magnets.

Abstract: A shaft is fixed within a motor housing in an electric motor unit. The shaft is provided with bearing sections having herringbone-shaped grooves formed therein. The shaft is inserted into a hollow cylindrical spindle and the journal sections in the smooth inner surface of the spindle are allowed to face the bearing sections so as to constitute a dynamic pressure type radial bearing supporting the spindle in the radial direction. Stator ring magnets are fixed to the motor housing, and rotor ring magnets are fixed to the hollow cylindrical shaft. The inner surface of the stator magnets faces the outer surface of the ring magnets. These magnets are magnetized such that the mutually facing regions have opposite magnetic poles. The stator and rotor magnets form a magnetic thrust bearing; that is, the spindle is suspended by the attractive force generated between the magnets.

Abstract: A hydrokinetic spindle including a housing having a bearing in which the journal portion of a shaft is mounted. The shaft has a helical groove having a progressively decreasing cross-section formed on the journal surface thereof and extending from one end of the journal portion to the other which picks up a predetermined amount of fluid lubricant from fluid pickup posts leading from at least one fluid reservoir formed in the housing and directs the lubricant to and upon the shaft under pressure thereby maintaining a film of fluid lubricant under pressure between the shaft and the bearing of the housing. The housing and shaft are sealed in an artificial atmosphere.

Abstract: This disclosure is concerned with improvements in hydrostatic guide bearings of a shaft in which the journal of the shaft takes on the form of a sleeve and the bearing comprises a first and a second set of chambers placed within concentric races respectively opposite the internal and external walls of the journal.