Abstract: Disclosed is a double-layer oil film lubrication analysis method and system based on a floating bushing. The method includes: determining a roller motion track and a floating bushing motion track according to a roller displacement and a floating bushing displacement; determining, when the motion tracks are closed end to end, minimum values of inner-layer and outer-layer oil film thickness of the floating bushing according to an oil film thickness at each moment; and determining that an abnormality exists in double-layer oil film lubrication when either of the minimum values of the inner-layer and outer-layer oil film thickness of the floating bushing is less than a preset oil film thickness threshold value. According to the present disclosure, more accurate abnormality analysis of double-layer oil film lubrication can be realized.

Abstract: In order to effect a seal a porous material which comprises one side of two opposing surfaces is used to restrict and evenly distribute externally pressurized gas, liquid, steam, etc. between the two surfaces, exerting a force which is opposite the forces from pressure differences or springs trying to close the two faces together and so may create a non-contact seal that is more stable and reliable than hydrodynamic seals currently in use. A non-contact bearing is also disclosed having opposing surfaces with relative motion and one surface issuing higher than ambient pressure through a porous restriction, wherein the porous restriction is part of a monolithic porous body, or a porous layer, attached to lands containing a labyrinth, the porous restriction and lands configured to not distort more than 10% of a gap created from differential pressure between each side of the porous restriction.

Abstract: An example hydraulic motor comprises: a stator comprising (i) a stator body having plurality of roller pockets, wherein the stator body comprises a plurality of grooves that are longitudinally-extending, and (ii) a plurality of rollers disposed respectively in the plurality of roller pockets; a rotor having a plurality of external teeth configured to engage with the plurality of rollers of the stator, such that the plurality of rollers and the plurality of external teeth define fluid chambers therebetween configured to expand and contract as the rotor rotates within the stator; and an anti-cogging passage configured to provide pressurized fluid from at least one of the fluid chambers to at least one groove of the plurality of grooves of the stator body, such that pressurized fluid provided to the at least one groove applies a radially-inward force on a respective roller toward the rotor.

Abstract: A dual membrane restrictor adapted to be connected to an oil supplying device, a loading device, and a recycling device is provided. The dual membrane restrictor includes a casing and first and second membranes. The casing has a first channel connected to the oil supplying device, first and second chambers, a second channel connected to the loading device, and a third channel connected to the recycling device. The first membrane is disposed in the first chamber divided into first upper and lower chambers by the first membrane. The first channel is connected to the first upper chamber. The second membrane is disposed in the second chamber divided into second upper and lower chambers by the second membrane. The second upper chamber is connected to the first lower chamber and the second channel. The second lower chamber is connected to the second channel and the third channel.

Abstract: A linear motion mechanism includes: a shaft; a base member having a through hole through which the shaft can be inserted; a static pressure bearing provided between the shaft disposed in the through hole and the base member to slidably support the shaft relative to the base member by introducing a pressurized fluid to the shaft; and an annular member provided between the static pressure bearing and the base member to elastically support the static pressure bearing.

Abstract: A roll arrangement for rolling rolling material in a rolling system. The roll arrangement includes a roll that is rotatably mounted by its roll journal in a bearing bush of a chock. A ring gap for receiving a lubricant is formed between the bearing bush and the roll journal. The ring gap is sealed both on the ball side of the chock and on the side of the chock away from the balls, using sealing rings. In order to increase the load capacity or the rolling force of a roll arrangement while maintaining or reducing the construction size thereof and without the roll arrangement overheating, discharge channels are provided in a through-flow angular range of the bearing bush for discharging the lubricant out of the ring gap into an oil-receiving chamber.

Abstract: A pneumatic bearing assembly for a linear guide rail system. The pneumatic bearing assembly provides a substantially frictionless bearing surface between the bearing assembly and the linear guide rail system. The bearing assembly includes a bearing housing to support a payload on the guide rail system and a bearing insert in an interior chamber of the housing. A plurality of pneumatic passages communicate a pressurized pneumatic source through the bearing housing to an interior surface of the bearing insert. The unique orientation of the plurality of pneumatic passages distributes the pressurized pneumatic source to provide a pneumatic cushion between the bearing assembly and the linear guide rail system.

Abstract: A bearing apparatus includes a cylindrical sleeve, a shaft rotatably inserted in the sleeve, lubricating oil arranged in a gap defined between an inner circumferential surface of the sleeve and an outer circumferential surface of the shaft, a seal member arranged at an axially upper end portion of the sleeve projecting from the sleeve, and an annular member fixed to an outer circumferential surface of the axially upper end portion of the shaft to rotate together with the shaft. The annular member includes a projecting portion projecting axially downward. The seal member and an axially lower end portion of the projecting portion overlap each other when viewed in at least one of the axial direction or a radial direction.

Abstract: A journal bearing, in which a lower half carrier ring is disposed on the outer peripheral side of a horizontally installed rotating shaft, and an upstream side pad and a downstream side pad are disposed on the inner side of the lower half carrier ring, includes an upstream side oil supply portion and downstream side oil supply portion which supply lubricant oil to the upstream side pad and downstream side pad, the bearing being characterized in that the supply quantity of lubricant oil supplied from downstream side oil supply nozzles of the downstream side oil supply portion is adjusted so as to be less than the supply quantity of lubricant oil supplied from upstream side oil supply nozzles of the upstream side oil supply portion.

Abstract: A hydrostatic bearing apparatus includes a bearing metal having a hydrostatic portion that allows a grinding wheel shaft to be rotatably supported. The hydrostatic portion has a bearing clearance, a bearing surface portion, a plurality of pockets, and partition plates. Clearances are each formed between the corresponding partition plate and an edge of the corresponding pocket in a rotating direction of the grinding wheel shaft. The clearances are formed in the pocket at upstream and downstream ends in the rotating direction. The bearing clearance has a first bearing clearance and a second bearing clearance. The second bearing clearance is larger than the first bearing clearance.

Abstract: A rotary vacuum pump, for instance a vane pump, has at least one circumferential groove (6) between facing side surfaces of the rotor (2) and of the rotor guide (3) for receiving a lubricating and sealing fluid. The circumferential groove (6) is a partial annular groove, which has an angular extension of less than 360° and has at least one interruption enabling creating a hydrodynamic fluid bearing in a region opposite a discharge region of the pump (1; 101; 121; 201), over the whole axial extension of the facing surfaces. A method of lubricating a rotary vacuum pump is also provided.

Abstract: A bearing with axial variations may include two or more different zones along its axial length either on the surface of a bore formed in the main body of the bearing with axial variations or on the outside diameter thereof. Each zone may include one or more radial holes in fluid communication with one or more grooves, respectively, wherein each groove may be positioned adjacent an interface between a rotating member and a non-rotating member.

Abstract: The invention relates to an installation part for mounting an upper support roll in a roll stand. The installation part has, on its cambered side, a lubricant receiving space, from which at least one lubricant drain hole (130) extends, in the lower region of the installation part, in the direction of the drain side of the installation part.

Abstract: An oil-retaining bearing fan device includes a fan base seat, at least one oil-retaining bearing and at least one magnetic member. The oil-retaining bearing is disposed in a bearing hole of the fan base seat. The oil-retaining bearing has at least one receiving hole for receiving the magnetic member therein. The magnetic member serves to apply a magnetic attraction force to a shaft of the fan device to make the shaft quickly restore to its optimal operation position so as to reduce wear and lower the noises and vibration of the fan device in operation. Therefore, the lifetime of the fan device can be prolonged.

Abstract: Coast-down bearing apparatus and methods are provided. The coast-down bearing includes a plurality of segments each having a radius of curvature substantially equal to an outer radius of a shaft and spaced radially therefrom to define a clearance, with the plurality of segments being configured to receive the shaft when a magnetic bearing drops the shaft. The coast-down bearing also includes a plurality of slots disposed between adjacent ones of the plurality of segments.

Abstract: Multi-recess hydrostatic journal bearings support a rotating shaft and have inclined surfaces, each inclined surface forming a variable radial gap with the surface of the shaft, the variable gaps converging in the direction of rotation of the shaft to increase hydrodynamic forces, reduce a turbulent component of shear friction, and improve the thermal stability of the journal bearing. The inclined surfaces can be formed in one or more of portions of recess bottoms in recesses, portions of gap lands surrounding recesses, and portions of an inner surface of a bushing.

Abstract: A connection element able to be located between a part or neck of a rolling roll and a relative housing bushing as present in a chock for rolling stands, including a first external element and a second internal element, mating and coupled, wherein the second internal element has internally a seating at least partly truncated cone shaped for coupling with the neck of the rolling roll.

Abstract: This invention relates to bearings, and more specifically is directed to active hydrostatic bearings destined for large heavily loaded reciprocating internal combustion engines, like ultra high compression ratio Diesel cycle engines, and homogeneous charge compression ignition (HCCI) and detonation engines working on stoichiometric fuel/air mixture. A fluid handling system therefore, method and apparatus are also disclosed.

Abstract: There are provided a hydrodynamic bearing assembly and a motor including the same. The hydrodynamic bearing assembly includes: a sleeve supporting a shaft and forming a bearing clearance filled with a lubricating fluid; a housing enclosing an outer peripheral surface of the sleeve and including a flange part formed in an upper end portion thereof and extended outwardly; a rotor hub coupled to an upper end portion of the shaft and including an extension wall part extended to be disposed outwardly of the housing; a stopper member fixed to the extension wall part while being disposed under the flange part of the housing, and forming, together with an outer peripheral surface of the housing, a space in which a liquid-vapor interface is formed; and a cover member coupled to a lower end portion of the housing. The sleeve and the housing include first and second circulation holes formed therebetween.

Abstract: There are provided a hydrodynamic bearing assembly and a motor including the same. The hydrodynamic bearing assembly includes: a sleeve having a shaft hole into which a shaft is rotatably inserted; and a hub fixed to an upper end of the shaft and extended in an outer radial direction, wherein an upper surface of the sleeve and a lower surface of the hub have an oil interface formed therebetween to seal oil.

Abstract: There is provided a bearing assembly including: herringbone-shaped first and second fluid dynamic pressure parts formed in upper and lower portions of at least one of an outer peripheral surface of a shaft and an inner peripheral surface of a sleeve in an axial direction to be spaced apart from each other; and a first auxiliary fluid dynamic pressure part formed to be bent upwardly from an end portion of a lower groove of the herringbone-shaped first fluid dynamic pressure part in an axial direction.

Abstract: A bearing unit for a disk drive device is formed by a sleeve concave portion and a shaft concave portion, and is provided with a capillary seal portion in which the gap between the sleeve concave portion and the shaft concave portion is increased in diameter toward the hub side of the sleeve. Assuming that: the outer circumferential diameter at the tilt starting end on the base member side of the shaft concave portion is D0; the inner circumferential diameter at the tilt starting end on the hub side of the sleeve concave portion is D1; the facing outer circumferential diameter of the shaft concave portion, which faces, in the radial direction, the inner circumference at the tilt starting end of the sleeve concave portion, is D2; and the diameter of the most concave inner circumference of the sleeve concave portion is D3, D2 is smaller than D0, D3 is larger than D1, and the difference between D3 and D0 is larger than that between D0 and D2.

Abstract: A dynamic bearing device allows production of a smaller housing at low cost and suppresses ion elution from the resin portion to thereby maintain cleanliness in the dynamic bearing device and exert a desired bearing performance. A dynamic bearing device 1 is equipped with a bearing sleeve 8 fixed to the inner periphery of the housing 7, and a rotary member rotatable relative to the bearing sleeve 8 and the housing 7, in which the rotary member is supported in the radial direction and the thrust direction in a non-contact manner by a dynamic pressure action of a lubricant fluid generated in a bearing clearance. The housing 7 is formed by injection molding of a resin composition containing polyphenylene sulfide (PPS) as the base resin and PAN type carbon fibers as a filler.

Abstract: A housing of a Roots pump is configured by joining a lower housing member and an upper housing member that are separable from each other. With the upper and lower housing members joined together, an upper accommodating portion and a lower accommodating portion form a front bearing accommodating portion and a rear bearing accommodating portion, which accommodate whole bearings, respectively. The Roots pump further includes bearing holders attached to the bearings and fixed to the lower housing member so that the bearings are received in the lower accommodating portion in a positioned state.

Abstract: A groove is provided in the periphery of a pressure receiving area of a pressure receiving surface opposing to the load of axis weight within a bearing surface supporting an axis, and a liquid supply route communicating with the groove is provided so that liquid is supplied to the groove through the liquid supply route. In such a configuration, a bearing having a simple structure and a high compact load capacity and a liquid cooling type screw compressor using the above bearing are provided.

Abstract: A method of fabricating a bearing surface for a gas or air bearing is described. The method comprises taking a bulk bearing portion having at least one bearing surface region and providing a coating on the bearing surface region to define at least one gas pocket. The at least one gas pocket has a depth substantially equal to the thickness of the coating. In one example, laser ablation is used to remove part of the coating to form the gas pockets. The coating may be an anodised coating and the bulk bearing portion may be formed from aluminium. An air bearing component formed using the method is also described.

Abstract: A self-compensating hydrostatic journal bearing is disclosed, which is substantially a base provided for a spindle to mounted thereat passing through a hole thereof, while allowing a gap to be formed between the circumference surface of the hole and the spindle for a hydraulic fluid to flow therethrough. There are at least two oil holes formed on the base, and correspondingly, there are at least two first chambers formed on the circumference surface for allowing each first chamber to be in fluid communication with one of the at least two oil holes, and for each first chamber, there is one second chamber being arranged in the vicinity thereof. When the spindle is forced to bias, the gap axially opposite to the bias is changed for causing the hydraulic fluid to flow inside the channels between the first chambers and the second chambers correspondingly and thus accomplishing a fluid self-compensating process.

Abstract: A contoured region is disposed within a capillary buffer of a Fluid Dynamic Bearing. In one embodiment, the contoured region comprises at least one defined edge for arresting the displacement of a lubricant within the capillary buffer.

Abstract: A plain bearing assembly for mounting a blade to a hub of a wind turbine includes an outer member mountable to one of the blade or hub, and an inner member mountable to the other of the blade or hub and movable relative to the outer member. The plain bearing further includes fluid cavities associated with one of the outer or inner member and arranged to confront the other of the outer or inner member. The fluid cavities are coupled to a pressure source for establishing a pressurized fluid film between the inner and outer members. A method includes monitoring at least one parameter of the fluid film, comparing the at least one parameter to a threshold criteria, and altering a dynamic state of the wind turbine and/or altering the state of the blade bearing assembly if the threshold criteria is exceeded.

Abstract: A wind turbine main bearing realized to bear a shaft of a wind turbine, which shaft is caused to rotate by a number of blades connected to the shaft is disclosed. The wind turbine main bearing includes a fluid bearing with a plurality of bearing pads arranged about the shaft. Also disclosed is a wind turbine with a number of blades connected to a shaft and realized to rotate the shaft, which wind turbine includes as main bearing a wind turbine main bearing. Further described is a method of performing maintenance on a wind turbine, including the steps of halting a rotation of the shaft, operating a lifting arrangement to raise the shaft, and removing a bearing pad of the wind turbine main bearing from the bearing housing of the wind turbine main bearing.

Abstract: A hydrodynamic type oil-impregnated sintered bearing includes a porous bearing body of sintered metal having a bearing surface in which hydrodynamic pressure generating grooves slating against an axial direction are provided. Lubricating oil or the base oil of lubricating grease to be impregnated into the bearing body is selected from among (a) mixtures of poly-?-olefin or hydrogenated compound thereof and ester and (b) ester. The ester is preferably polyol ester. In the cases of the lubricating grease, the thickener of the lubricating grease is preferably composed of urea compound. A plurality of bearing surfaces may be formed on the inner periphery of the bearing body so as to be separated from one another. The hydrodynamic type oil-impregnated sintered bearing may be suitably applied to a spindle motor for information equipment.

Abstract: A method of positioning a shaft and associated seal in turbomachinery utilizing electromagnetic bearings. The method includes applying electrical power to the electromagnetic bearings' windings, the shaft center being in a first position and the shaft being in contact with the associated seal. Power adjustment to the electromagnetic bearings moves the shaft. Shaft movements can manipulate the seal, the movements being of decreasing amplitude to a position in which the seal is out of contact with the shaft when the shaft is rotated at its centered position during normal operation. The shaft is in its centered position during normal operation when the shaft axis is substantially coaxial with an axis of the electromagnetic bearings. Movements of decreasing amplitude may include oscillations of decreasing amplitude about one or more axes, or may include a spiral rotation with a decreasing radius to move the shaft center from initial to final positions.

Abstract: A plain bearing assembly for a wind turbine includes a bearing housing having a passageway configured to receive a shaft and a bearing surface defining the passageway and having a cylindrical configuration. The bearing surface includes lower and upper portions defined relative to a first midline plane and first and second sides defined relative to a second midline plane. A plurality of fluid cavities is in the bearing surface, wherein at least one fluid cavity is located in the lower portion and at least one fluid cavity is located in the upper portion. The at least one cavity in the lower portion includes first and second pairs of longitudinally spaced fluid cavities on the first and second sides of the bearing surface respectively. A wind turbine having such a plain bearing assembly is also disclosed.

Abstract: A hydrodynamic type oil-impregnated sintered bearing includes a porous bearing body of sintered metal having a bearing surface opposed to a sliding surface of a rotating shaft, hydrodynamic pressure generating grooves slanting against an axial direction provided in the bearing surface, and lubricating oil or lubricating grease impregnated in pores inside the bearing body, wherein a rate of area of surface holes on the bearing surface is set within a range of 3%-15%, the surface holes being distributed substantially uniformly over the whole area of the bearing surface including areas of the hydronamic pressure generating grooves, wherein the lubricating oil or a base oil of the lubricating grease forms a lubricating film in a bearing clearance, and wherein the lubricating oil or a base oil of the lubricating grease is a lubricating oil selected from among mixtures of poly-?-olefin or hydrogenated compound thereof and a defined phosphoric ester.

Abstract: A bearing apparatus includes a shaft, a thrust cup including an annular potion and a cylindrical portion, a rotating member including a through hole defined therein, and a lubricating oil. A second gap defined between a lower surface of the rotating member and an upper surface of the annular portion of the thrust cup includes a first region in communication with a capillary seal portion, and a second region positioned radially inward of the first region and having an axial dimension smaller than that of the first region. A lower end portion of the through hole is open at a location radially outwardly away from a boundary between the first and second regions, so that a local circulation of the lubricating oil arises within the first region during rotation of the rotating member.

Abstract: A lid member (10) is formed in a cup-like shape while having a plate portion (10a) and a cylindrical fixed portion (10b) axially protruding from an outer peripheral end of the plate portion (10a). An outer peripheral surface (10b1) of the fixed portion (10b), which serves as a fixation surface (B), is fixed to an inner peripheral surface (7a) of a housing (7) as an outer member (A). An axial dimension of the fixation surface (B) is larger than a thickness of the plate portion (10a), and hence it is possible to thinly-form the plate portion (10a) and to increase a fixing force between the lid member (10) and the housing (7). As a result, an axial dimension of a fluid dynamic bearing device can be reduced and durability thereof can be simultaneously increased.

Abstract: A hydrostatic bearing pad in which separation between a housing and a pad member and entry of an adhesive into an air supply groove are prevented to obtain stable bearing performance is provided. The hydrostatic bearing pad includes the pad member having a bearing surface forming a hydrostatic bearing and having air supply holes formed therein, and the housing bonded to the pad member with the adhesive. The air supply groove for supplying compressed gas to the pad member is formed in a surface of the housing bonded to the pad member, in a manner corresponding to arrangement of the air supply holes. An adhesive inflow groove is formed between a bonded portion, where the housing and the pad member are bonded to each other with the adhesive interposed therebetween and the air supply groove. The adhesive inflow groove is formed along the air supply groove in the surface of the housing bonded to the pad member.

Abstract: An inertial navigation system is provided. The system includes a sensor block, an outer shell that substantially surrounds the sensor block and a plurality of gas pads connected to the outer shell that float the sensor block in gas creating a near frictionless environment to allow the sensor block to rotate in all directions. Each of the plurality of gas pads is adapted to receive pressurized gas. The outer shell and the sensor block are separated by a gap created by the pressurized gas at each pad.

Abstract: A method of fabricating a bearing surface (11,13) for a gas or air bearing (2) is described. The method comprises taking a bulk bearing portion (30; 44) having at least one bearing surface region and providing a coating (32; 42) on the bearing surface region to define at least one gas pocket (34; 40). The at least one gas pocket (34; 40) has a depth substantially equal to the thickness of the coating (32; 42). In one example, laser ablation is used to remove part of the coating (32; 42) to form the gas pockets (34; 40). The coating (32; 42) may be an anodised coating and the bulk bearing portion (30) may be formed from aluminium. An air bearing component formed using the method is also described.

Abstract: An oil film bearing (1) for roll pins (4), which or whose pin bush (3) that is placed thereon is surrounded by a bearing bush (3) placed in an insert (2). The bearing bush has at least two inner lying hydrostatic pockets (9, 9?), which are arranged, in essence, in a common axial line and which can be supplied with a pressure medium via a check valve (18) and via boreholes (6, 6?) extending inside the bearing bush (5). Throttles (15, 15?) inside the boreholes (6, 6?) ensure an optimal hydrostatic bearing even when the roll pin (4) or the pin bush (3) is in an oblique position inside the bearing bush (5). The aim of the invention is to improve an oil film bearing of the aforementioned type whereby economically assuring the hydrostatic function of the bearing and in which the inspection of the throttles (15, 15?) is possible without further ado.

Abstract: This invention introduces a new category of engineered surfaces and corresponding production processes for better wear resistance and lower friction loss. The structured surfaces can be applied on many automobile components with frictional surfaces. The composite structure settles the usual conflicts between surface functions and stresses. Two sets of multiple-step processes are introduced to achieve high production efficiency and low cost. Unlike traditional surface technologies that generate single and uniform layers on the whole part surface, the new technology processes the part surface selectively for more effective surfaces with versatile functions.

Abstract: A hydrodynamic fluid film bearing for supporting a rotation shaft of a turbo or rotary apparatus includes a sleeve having a circular inner opening for receiving a rotation shaft therein, at least one metallic foil member of arc shape having one end fixed to the inner surface of the sleeve and arranged along the inner opening of the sleeve, and at least one elastic member disposed at the sleeve between the sleeve and the foil member. A bearing housing for receiving a bearing of a rotary apparatus is further provided, in which the bearing housing includes a circular opening for receiving the bearing therein, and the circular inner opening of the bearing housing includes grooves for cooling air passage formed at regular interval in the axial direction on the inner surface of the bearing housing. The bearing received in the bearing housing is preferably a hydrodynamic fluid film bearing.

Abstract: In a radial minute gap between a substantially columnar shaft and an inner peripheral face of a substantially cylindrical sleeve, oil is retained and a radial dynamic pressure bearing is formed. A plurality of recessed portions are arranged in a circumferential direction on at least one of an outer peripheral face of the shaft and the inner peripheral face of the sleeve and a first hill portion is provided to an axial end portion of each the recessed portion. Thus, it is possible to achieve a dynamic pressure bearing with which sufficient radial shaft support can be obtained in spite of a short axial length.

Abstract: A hydraulic bearing that supports a rotating shaft comprises a bearing metal. On a surface of the bearing metal, a hydrostatic pocket and a land portion are formed. The land portion is defined by the hydrostatic pocket and generates hydrodynamic pressure in response to a rotation of the rotating shaft. The hydraulic bearing further comprises a pressure fluid supplying source and an oil-supplying hole. The oil-supplying hole is opened in the hydrostatic pocket and provides pressure fluid from the pressure fluid supplying source to the hydrostatic pocket. On the land portion, a drain hole that drains the fluid is formed. On the way of a drain passage, a check valve is disposed. Since the drain hole does not separate the land portion, deterioration of bearing rigidity is restrained. Further, since the fluid is drained through the drain hole, thermal expansion of the bearing metal due to heat generation of the fluid is restrained.

Abstract: A fluid dynamic bearing has a shaft (11) fitted in a sleeve (12) for rotation, with a fluid filled therebetween. The shaft (11) and/or sleeve (12) is formed with a pattern consisting of grooves (111g) and lands for generating a pressure distribution in the fluid and then covered with a diamond-like carbon film (11c) over the surface of the grooves and the surface of the lands.

Abstract: A hydraulic bearing that supports a rotating shaft comprises a bearing metal. On a surface of the bearing metal, a hydrostatic pocket and a land portion are formed. The land portion is defined by the hydrostatic pocket and generates hydrodynamic pressure in response to a rotation of the rotating shaft. The hydraulic bearing further comprises a pressure fluid supplying source and an oil-supplying hole. The oil-supplying hole is opened in the hydrostatic pocket and provides pressure fluid from the pressure fluid supplying source to the hydrostatic pocket. On the land portion, a drain hole that drains the fluid is formed. On the way of a drain passage, a check valve is disposed. Since the drain hole does not separate the land portion, deterioration of bearing rigidity is restrained. Further, since the fluid is drained through the drain hole, thermal expansion of the bearing metal due to heat generation of the fluid is restrained.

Abstract: A hydraulic bearing device that supports a rotating shaft comprises a bearing metal. On a surface of the bearing metal, a hydrostatic pocket and a land portion are formed. The land portion is defined by the hydrostatic pocket and generates hydrodynamic pressure. The hydraulic bearing device further comprises a pressure fluid supplying source and an oil-supplying hole. The oil-supplying hole is opened in the hydrostatic pocket and provides pressure fluid from the pressure fluid supplying source to the hydrostatic pocket. On the land portion, a drain hole that drains the fluid is formed. Since the fluid is drained through the drain hole, thermal expansion of the bearing metal due to heat generation of the fluid is restrained. Moreover, since the drain hole does not separate the land portion, deterioration of bearing rigidity is restrained.

Abstract: The hydrostatic fluid bearing comprises a cylindrical stator having orifices for introducing a fluid under pressure, on its inside surface the stator has a split ring constituted by an assembly comprising a plane metal plate and a layer of self-lubricating composite material. The layer of composite material has cells for surrounding orifices for introducing fluid under pressure, once the assembly has been put into place inside the stator.

Abstract: A hydrodynamic gas bearing structure includes a columnar shaft body (1) and a hollow cylindrical bearing body (2) arranged opposing the shaft body (1) with a space (3) maintained in the radial direction therebetween. In a cross section perpendicular to the central axis of the shaft body (1) and the bearing body (2), either the shaft body (1) or the bearing body (2) has a convex polygonal shape with at least ten vertexes. Accordingly, a hydrodynamic gas bearing structure can be obtained in which ½ whirl can be suppressed even at a high speed rotation of 20,000 rpm or higher and run out associated with the rotation can be suppressed.

Abstract: In a dynamic pressure bearing device which has a shaft (3), a bearing (10) rotatable relative to the shaft (3), and capillary seal portions (13, 14) for holding a lubricating fluid (15) in a bearing clearance and in which the shaft (3) and the bearing (10) are relatively rotatably supported by dynamic pressure of the lubricating fluid (15) in the bearing clearance is scattered by centrifugal force so that the lubricating fluid (15) is kept in a constant quantity by the capillary seal portions (13, 14).