Abstract: A seal assembly (10, 110) has an inner seal carrier (14, 114) with seals (16, 116, 18, 118), an outer carrier (30, 130) with inner curved surface (144) matching an outer curved surface (146) of the inner seal carrier for angular pitch adjustment of 3° to 5° for the inner seal carrier within the outer carrier, a flexible seal (36, 136) between the outer carrier and the bearing housing (28, 128), and oil within a cavity (20, 120) between the seals, preferably above atmospheric pressure. Shoulder bolts (140) allow lateral movement of the seal assembly with respect to the bearing housing. The seal assembly allows for misalignment and lack of parallelism of the shaft relative to the bearing housing whilst preventing contamination of the bearing.

Abstract: A rotation system (10) is disclosed having at least one axial gas bearing, containing: a housing (11), a shaft (12) that can be rotated relative to the housing (11), at least one bearing plate (13) attached to the shaft (12), and at least one bearing assembly (14) which supports the bearing plate (13) relative to the housing (11), via an axial gas bearing. The bearing assembly (14) has, from inside to outside, a radially inner region (15) supporting the bearing plate (13), a radially central region (16) and a radially outer region (17) held by the housing (11). The radially inner region (15) contains at least one axial bearing element (19) and at least one retention element (20). The bearing plate (13) is supported by the axial bearing element (19), and the retention element (20) holds the axial bearing element (19) in the axial direction.

Abstract: A bearing assembly is for movably coupling first and second members, one being movable relative to the other. A plain bearing section includes an inner ring connectable with the first member and an outer convex bearing surface. An outer ring is disposed about the inner ring and has an inner concave bearing surface disposed against the inner ring bearing surface. The two bearing surfaces are formed such that one bearing surfaces slides against the other when the movable member displaces about a first axis and two bearing surfaces engage to prevent displacement between the two rings when the movable member displaces about a second axis. An elastomeric bearing section is disposed about the plain bearing section, is connected with the second member and formed such that at least a portion of the elastomeric bearing section flexes when the movable member angularly displaces about the second axis.

Abstract: A hydrodynamic plain bearing includes a bearing shell having an inner surface which forms a bearing surface for a rotating shaft or the like. The bearing surface has a plurality of surface segments separated from each other and disposed successively in the circumferential direction of the bearing shell. At least the bearing surface or the entire bearing shell is made from CuCr1Zr.

Abstract: A composite sliding bearing is disclosed. The composite sliding bearing has an inner ring, formed of split rings halved by a center in an axial direction, which has V-section inclined surfaces formed on the outer diameter surfaces of the split rings, bearing pads disposed separately on the inclined surfaces of the split rings along the outer diameter surface of the inner ring, and an outer ring on the inner diameter surface of which is formed a V-section umbrella-shaped inclined surface corresponding to the outer diameter surface of the inner ring. A radial load and axial load applied to the bearing are supported by sliding the inner diameter surface of the outer ring on the sliding surfaces of the bearing pads in a condition in which the bearing pads are fluid lubricated.

Abstract: A device of the axial-directional oil chamber of hydrostatic spindle comprises integrated oil seal structures at both the axial direction and the radial direction. The oil seal structures increase the work area of the oil chamber by extending and thus connecting an axial-directional oil seal edge to a radial-directional oil seal edge. Then, the rigidity of the axial hydrostatic bearing can be increased, and thus the application capability of the hydrostatic spindle can be upgraded to perform the multi-task machining from the mono-task machining.

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 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 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: The fluid dynamic bearing device includes a housing, two bearing sleeves fixed to the housing at positions axially spaced apart from each other, and a shaft member inserted along inner peripheries of the bearing sleeves. The housing includes a spacer portion protruding further radially inwardly than inner peripheral surfaces to which the bearing sleeves are fixed. An axial fluid path is formed in the spacer portion, and the axial fluid path communicates to flow paths formed by axial grooves of the bearing sleeves.

Abstract: In a spindle motor, a capillary seal portion having a radial dimension that decreases in an axially downward direction, and a labyrinth seal portion arranged above the capillary seal portion are defined between an outer circumferential surface of a rotating member and an inner circumferential surface of a tubular portion. The capillary seal portion includes a liquid surface of a lubricating oil positioned therewithin. The radial dimension of the labyrinth seal portion is smaller than the radial dimension of an upper end portion of the capillary seal portion, so that the labyrinth seal portion contributes to reducing evaporation of the lubricating oil.

Abstract: The invention relates to a fluid dynamic bearing system that has a stationary sleeve, a stationary shaft disposed in the sleeve and bearing disks disposed on the sleeve and shaft which form an annular disk-shaped space between each other in which an annular disk-shaped component is disposed. A bearing gap filled with a bearing fluid is formed between the stationary and the rotating bearing construction.

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: Provided is a spindle motor having a hydrodynamic bearing with an improved structure to prevent oil leakage due to a centrifugal force generated when the motor is rotating. In the spindle motor, an oil gap is formed between a rotor and a fixing body to form the hydrodynamic bearing to rotate the rotor, and an oil groove is formed in a surface of the rotor or the fixing body, which faces the oil gap. Also, a taper seal is formed in an area that extends from the oil gap and contacts the air, between the rotor and the fixing body, and the rotor constituting the taper seal is placed of the rotation center of the fixing body. Thus, thus the amount of oil in the taper seal is minimized and oil leakage can be stably prevented.

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: 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: An air spindle is provided which allows high-speed operation without reducing the bearing stiffness in the air spindle by reducing the heat generation at bearing portions. By increasing the number of nozzles for the radial bearing or increasing the axial distance between the nozzles, the ratio of the supply air flow rate Q to the bearing stiffness H is set at 2-10 to release heat generation at the bearing portions to outside by the gas.

Abstract: The bearing mainly includes an inner groove and at least a passage. The groove is arranged on an inner surface of the bearing and connected with a reservoir on one end of the bearing by the passage to induce the outflow lubricant backflow to the groove.

Abstract: A spindle motor is disclosed which allows more excellent abrasion resistance and productivity exhibited by making the thrust to be integrally formed at driving shaft and by making each of kinetic pressure-generating grooves that generate fluid kinetic pressure in axial direction to be formed at different formation position from each other that may be less influenced than ever by force of friction with fluid material.

Abstract: A journal bearing apparatus capable of varying the clearance between a bush which protrudes from the inner surface of a sleeve in which a rotation shaft is inserted and the outer surface of the rotation shaft, in the longitudinal direction of a first dynamic pressure generating groove. Moreover, a journal bearing apparatus is capable of varying the clearance between one end of the rotation shaft and the surface of a thrust bearing, in the diametral direction of a second dynamic pressure generating groove. The clearance becomes wider towards the central part from the ends of the bush, or towards the central part from the edge parts of the surface of the thrust bearing. The shape of the end of the bush or the thrust bearing is preferably a circular arc. Thereby, the fluid pressure on the rotation shaft which faces the first and second dynamic pressure generating grooves is uniform.

Abstract: A feed screw mechanism includes a nut having a female thread, and a feed screw shaft having a male thread screw-engaged with the female thread. A thrust pocket is formed along a flank of the female thread of the nut, and pressurized fluid is supplied thereto. A plurality of separated radial pockets are formed on the crest surface of the female thread of the nut, and pressurized fluid is supplied thereto. The thrust pocket is a continuous spiral groove formed along the flank of the female thread of the nut. This structure provides sufficient rigidity in both the radial and thrust directions while reducing the size of the feed screw mechanism.

Abstract: A spin index fixture has a housing which is provided with an air inlet shaft for permitting pressurized air to enter the housing and to propagate through grooves disposed along the outer surface of the sleeve. The air then enters into a clearance volume between the housing and the spindle and serves as an air bearing. The spindle is further provided with impelling recesses disposed circumferentially along the outside surface of the spindle at an axial location that is in alignment with the pressurized air inlets. The force of the air against the recesses rotates the spindle about its axis when the pressurized air supply contacts the recesses.

Abstract: An externally pressurized air bearing spindle comprises: a first cylindrical bearing portion having a journal bearing surface opposing an outer circumferential surface of a main shaft with a small journal bearing clearance therebetween, a thrust bearing surface opposing one end surface of a thrust plate disposed on the main shaft with a small thrust bearing clearance therebetween, and plural bearing nozzles formed in the journal bearing surface and the thrust bearing surface and arranged in planes perpendicular to an axis thereof; and a second cylindrical bearing portion having a thrust bearing surface opposing the other end surface of the thrust plate with a small thrust bearing clearance therebetween and plural bearing nozzles formed in the thrust bearing surface and arranged in a plane perpendicular to an axis thereof; the arrangement being such that the main shaft is supported on the bearing surfaces without contact by the action of compressed air fed through the bearing nozzles into the bearing clearance

Abstract: A dynamic pressure generating bearing includes a rotational body, a radial bearing provided adjacent to a center of the rotational body to rotatably support the rotational body around the radial bearing and at least one thrust bearing provided on one end of the radial bearing. When the rotational body is stably rotated, a minimum clearance generated between the rotational body and the thrust bearing is always greater than a minimum clearance generated between the rotational body and the radial bearing.

Abstract: A novel means for the design of the pockets of a hydrostatic spindle and the flow supply, collection, and pocket injection means to allow for very high speed rotation with a minimum of heat generation, mid maximum load capacity; furthermore the concept of self compensation is used to make the design insensitive to contaminants and thereby allow for the use of water based hydrostatic fluids, whereas the design of the compensator region is also advanced to facilitate high speed use. Accordingly, the present invention allows designers to increase the allowable speed and accuracy of rotary motion hydrostatic bearings. Design methodologies are presented for designing self compensating hydrostatic bearing spindle pockets and compensators to minimize the effects variation in stiffness with angular position, cavitation in bearing pockets, and turbulent shear power generation.

Abstract: A fluid bearing assembly for rotatably supporting a rotary-driven spindle having smooth bearing surfaces. Each bearing has a stationary housing holding an annular bearing race that presents a smooth continuous bearing surface facing a complementary bearing surface of the spindle; together the race and spindle define a continuous, thin, uniform crevice space. The smooth race bearing surface is interrupted by a plurality of circumferentially spaced pressure generating zones, each capable of dynamically compressing a fluid body contained in the zone into the crevice in either direction of rotation of the spindle at higher speeds. Pressurized fluid is supplied to flow through each zone and out of the crevice while exerting a predetermined hydrostatic force against the spindle at lower rotational speeds.

Abstract: A spindle device with a built-in motor comprises a casing, a working spindle having a large radius portion formed with a bore and a small radius portion extending from the large radius portion, the large radius portion being housed in the casing, and the small radius portion protruding from the casing and having a working tool mounted thereon, a cylindrical motor rotor attached to an inner surface of the large radius portion of the working spindle, a fixed shaft provided in the casing and loosely inserted into the motor rotor, and a motor stator mounted on an outer surface of the fixed shaft opposed to the motor rotor. The casing is formed with an air passageway having a plurality of injection nozzles which are open at an inner surface of the casing opposed to an outer surface of the large radius portion of the working spindle.

Abstract: The bearing pedestal for the rotating shaft 12 includes journal and axial thrust bearings 16 and 26, respectively. Both of the journal and thrust bearings have passages 70 and 80, respectively, and recesses 74 and 82 in the respective pad faces for flowing high pressure lubricant between the pads and the shaft to displace the shaft and pads relative to one another to minimize the required breakaway torque and metal-to-metal contact. Each thrust bearing includes a plurality of circumferentially spaced pads 26 and lubricant directors 30 between the pads. The lubricant director includes a rib 34 extending generally tangentially and radially outwardly to channel lubricant from a preceding pad to a succeeding pad in the direction of shaft rotation and to channel the lubricant for flow tangentially from the thrust bearing into an annular cavity 39 for return to sump 42.

Abstract: The fluid-tight coupling is designed for connecting a fixed hydraulic line with a rotary hydraulic line. The fixed line (1) carries on its end an axially movable tubular piston (7) provided with a hemispherical head (8); the rotary line (2) has an offset end portion (15), the axis (Y) of which is eccentric with respect to the axes (X) and (Z) of the pipes (1) and (2), this end portion (15) being also provided with a hemispherical head (16); between the two hemispherical heads (8, 16) is interposed a wobbling rotary core piece (17) formed with a central orifice (18) and with two opposed concave conical bearing surfaces for fluid-tight engagement with both hemispherical heads (8, 16) respectively. In a preferred embodiment, the axial thrust exerted on the hemispherical head (16) corresponding to the rotary pipe (2) is supported by a hydrostatic bearing (24, 25) and the rotary pipe (2) is also supported by a hydrostatic bearing (22).

Abstract: A static pressure gas bearing is incorporated in a housing wherein a slotted groove with a small volume and a throttling control valve are positioned close together. Compressed gas is injected onto the bearing surface from the slotted groove. This configuration provides a static pressure gas bearing in which it is difficult to develop self-induced vibration.

Abstract: A centrifugal classifier comprising a housing, which is provided with inlets for material to be classified and classifying air or with an inlet for material to be classified and classifying air and with outlets for fines and for coarses, and at least one rotor, which essentially consists of an annular series of blades and is movably mounted in the housing. The rotor is movably mounted in the housing by at least one bearing, which is adapted to be purged by a fluid and which serves also as a seal between the rotor or rotor shaft and the housing.

Abstract: A housing has a vertically extending cylindrical bore, with a radical bearing surface formed on the inner peripheral surface, and a thrust bearing surface formed on the inner bottom surface of the cylindrical bore. A shaft member which is supported rotatably in the cylindrical bore of the housing has a radial receiving surface and a thrust receiving surface respectively formed on the outer peripheral surface and the bottom surface. A dynamic pressure generating groove of a spiral shape is formed in at least one of the radial bearing surface and ther radial receiving surface. When the shaft member is rotated, a gas in the housing is sucked by the pumping action of the dynamic pressure generating groove and flows into a pressure chamber between the thrust bearing surface and the thrust receiving surface through a radial space between the radial bearing surface and the radial receiving surface. The pressure in the pressure chamber maintains the shaft member in a floating position by a predetermined amount.

Abstract: A high speed drilling system is disclosed for high speed drilling of very small holes in workpieces such as printed circuit boards. The X-Y positioning system includes air bearings to provide lift between the stationary guide beams, the crossbeam and the top table, and further includes a vacuum preloading apparatus for providing a preloading force between the table and the guide beam. The preload force dampens Z axis oscillations which can result in drill bit breakage. The top table is a lightweight honeycomb structure, whose effective rigidity is virtually that of the guide beam due to the vacuum preloading. The system includes pairs of spindles, one a conventional spindle for drilling holes larger than about 0.125 inches, and the other a high speed spindle for drilling holes in the range of about 0.003 to 0.125 inches. The high speed spindle includes a stationary spindle body carrying the stator of the rotary drive motor.

Abstract: A shaft support comprising a shaft supported by a radial and an axial static fluid bearing, which shaft is rotatably arranged in a bearing sleeve and is provided with a flange-shaped compensation member, of which a part is situated in a compensation space. The compensation space is connected to a pressure source so that a radially acting resulting force is exerted on the compensation member and the shaft. The shaft support is particularly suitable for use with comparatively accurate bearings having a comparatively high bearing capacity.

Abstract: A gas-static bearing including a bearing shell formed of porous material compacted at bearing surfaces thereof for supporting a shaft, the bearing surfaces being distributed over a first group of surfaces consisting of at least two cylindrical jacket surfaces disposed concentrically to one another and about a longitudinal axis of the bearing shells and a second group of surfaces consisting of a plurality of circular surfaces disposed in succession along the axis.

Abstract: A slidable vane motor is used in conjunction with an externally located combustion member in which fuel is burned and compresses air for delivery to the combustion member and expands the combusted gas resulting from the fuel combustion in the compressed air. The vane motor and combustion member thus cooperate to form an external combustion engine. The energy extracted from the expansion of the gas is greater than the energy required to compress the air. The energy difference is delivered by a drive shaft external to the engine. The motor vanes slide quasi radially in guiding slots as the motor rotates to cause volumes of air trapped between contiguous vanes to decrease and trapped volumes of gas to increase concurrently. The vanes are thus subjected to pressure differentials which are applied quasi normally onto the vane sliding surfaces. The resulting torque is reacted by the action of high pressure air cushions located between the cooperating surfaces of the vanes and their slots.

Abstract: An external combustion engine including a rotary motor providing the means for compressing air and expanding combusted gases, and an externally located combustion member in which fuel is burned. The combustion member comprises a sleeve and a free piston reciprocating therein, thereby forming combustion chambers between its two ends and the end closures of the sleeve, as it reaches the end of its stroke. The back and forth motion of the piston is independent of the rotation of the motor as these two components are not mechanically connected, having only ducting connections therebetween. The combustion member air admission, combusted gas exhaust, the fuel injection and the ignition are all timely controlled and activated as a result of the free piston motion and location in the sleeve. The fuel/air ratio is continuously monitored so as to prevent high combustion temperatures.

Abstract: The bore of a bearing bush for a gear pump has a first recess located in a zone of load concentration in the bore, the first recess being supplied with a fluid under pressure. A second recess in the bore is located wholly outside the zone in which concentrated loads occur and acts as a reservoir for fluid, to prevent cavitation within the bore as a result of low pressures caused by radical movements of a shaft within the bush. A passage connects the second recess with a zone of lower pressure within the pump.

Abstract: A vertical motor pump including an upper bearing and a lower bearing located on the motor side for journaling a rotary shaft for rotation at an upper portion and a lower portion respectively of a rotor, at least one of the upper and lower bearings being constituted by a ball bearing. The vertical motor pump further includes a hydrostatic lubricated bearing system for journaling the rotary shaft besides the ball bearing, for bearing a radial thrust during operation.

Abstract: A fluid bearing in which parts of the bearing land are free to move relative to the bearing member on which they are mounted, so that in use the speed of the relative movement of the two confronting surfaces that define the bearing clearance is less than the speed of relative movement of the bearing members themselves. This reduces the power losses due to shearing effects within the thin film of fluid continuously passing through the bearing clearance in contact with these confronting surfaces. The invention applies particularly to rotary bearings of journal and end-thrust type, in which the moving lands may be ring-shaped units, mounted for rotation about the bearing axis and supported by relatively friction-free bearings--for instance gas bearings--on the bearing member in which the bearing recess is formed.

Abstract: An axial thrust balancing system including a sleeve for balancing an axial thrust applied to a rotary shaft and a bush defining therebetween a clearance having arranged therein at least one pressure chamber for dividing the clearance into a plurality of smaller clearances. The axial division of the clearance reduced the ratio of the axial length of the clearance to the diameter of the sleeve and stabilizes the bearing characteristics of a film of fluid in the clearance, thereby inhibiting the generation of a self-excited vibration of the shaft up to a high rotation velocity.

Abstract: A gyro assembly including a rotor, stator, hysteresis motor and conical hydrodynamic bearings for supporting the rotor relative to the stator.

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.