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.

Abstract: A bearing system for reducing end clearance and axial vibrations includes a bearing housing and a bearing. The bearing is a thrust bearing and may be of any type, such as a flat thrust face, a taper land thrust bearing or a tilt pad thrust bearing. The bearing housing includes a cavity to hold the bearing. A fluid cavity is formed between the bearing and the bearing housing. At least one fluid passageway extends through the bearing housing to feed fluid to the fluid cavity. As fluid is introduced to the fluid cavity the pressure in the cavity moves the bearing outward, away from the bearing housing and towards the rotating thrust collar, reducing the clearance, or space, between the face of the bearing and the thrust collar, reducing or eliminating the vibrations.

Abstract: There is provided a spindle motor including: a lower thrust member fixedly attached to a base member; a shaft fixedly attached to at least one of the lower thrust member and the base member; a sleeve disposed on an upper portion of the lower thrust member and rotatably installed on the shaft; a rotor hub coupled to the sleeve to thereby rotate together therewith; and an upper thrust member fixedly attached to an upper end portion of the shaft and forming a liquid-vapor interface together therewith, wherein the sleeve has an inclination part formed at an upper end portion thereof so as to form the liquid-vapor interface together with the upper thrust member, the inclination part having an outer diameter larger in an upper portion thereof than in a lower portion thereof.

Abstract: A hydrodynamic axial sliding bearing is disclosed. The bearing includes a substantially planar sliding surface.

Abstract: There are provided a hydrodynamic bearing assembly and a method of manufacturing the same. The hydrodynamic bearing assembly includes: an oil sealing part formed between a fixed member and a rotating member; and an oil barrier film disposed so as to prevent leakage of oil from the oil sealing part and including a self-assembled monolayer formed on a surface of at least one of the fixed member and the rotating member. The oil barrier film may be easily formed at room temperature and be continuously used for a long period of time without being damaged due to external impacts.

Abstract: To manufacture a shaft member, which is excellent in both accuracy and strength at low cost, a shaft member (2) includes a shaft portion (21) and a flange portion (22) provided to one end of the shaft portion (21). The flange portion (22) has an annular shape, and the shaft portion (21) and the flange portion (22) are fixed by a welded portion (23), which is formed by applying a laser beam (35) to an upper end of an inner periphery thereof.

Abstract: Bearing assemblies and apparatuses are disclosed. Such bearing assemblies may be employed in bearing apparatuses for use in downhole motors of a subterranean drilling system or other mechanical systems. In an embodiment of the present invention, a bearing assembly includes a plurality of bearing elements distributed circumferentially about an axis. Each bearing element includes a superhard bearing surface. The plurality of bearing elements defines a plurality of gaps. Each gap is formed between circumferentially-adjacent bearing elements of the plurality of bearing elements. Further embodiments of the present invention include bearing apparatuses and downhole motors that may utilize any of the disclosed bearing assemblies.

Abstract: An axial piston machine includes a housing and pistons situated in cylinder bores of a rotatable cylinder member, which pistons are supported on a pivoting cradle, the pivoting cradle being supported via at least one pivoting bearing having a bearing gap that has fluid acting on it. The axial piston machine further includes a control and/or regulating device is provided for the control and/or regulation of the fluid pressure in the bearing gap.

Abstract: Hydrodynamic bearing assemblies and apparatuses are disclosed. Such hydrodynamic bearing assemblies may be employed in bearing apparatuses for use in downhole motors of a subterranean drilling system or other mechanical systems. In one embodiment of the present invention, a hydrodynamic bearing assembly includes a plurality of bearing elements distributed circumferentially about an axis. Each bearing segment includes a superhard bearing surface. The plurality of bearing elements defines a plurality of seams. Each seam is formed between circumferentially-adjacent bearing elements of the plurality of bearing elements. Further embodiments of the present invention include hydrodynamic bearing apparatuses and downhole motors that may utilize any of the disclosed hydrodynamic bearing assemblies.

Abstract: A bearing assembly has an outer housing, and an inner mandrel extending into outer housing. Radial bearing sleeves are positioned between the inner mandrel and the outer housing at both of ends of the outer housing. A thrust bearing assembly is positioned within the interior cavity of the outer housing, and includes a fixed bearing carrier fixed to the inner mandrel, first and second floating bearings carriers, and first and second pressure responsive fillers. Floating bearing carriers support hard face bearings that engage hard face bearings on the fixed bearing carrier to withstand axial loads. Pressure responsive fillers permit the floating bearing carriers limited angular adjustment in relation to the fixed bearing carrier to maintain their respective at least one hard face bearing in face to face relation notwithstanding deflections within required radial bearing tolerance.

Abstract: In a toroidal continuously variable transmission unit, a pair of guide surface portions 120, 120 are provided on a trunnion 15 so as to face oppositely each other and to extend in a direction which intersects a rotational center axis of a power roller 11 at right angles and intersects pivot shafts 14 at right angles. When a tangential force along a direction of the pivot shafts 14 is applied to the power roller 11, an outer circumferential surface 110 of an outer ring 28 can be brought into abutment with these guide surface portions 120, 120. By this, the toroidal continuously variable transmission unit with good machinability can be obtained in which the power roller together with the outer ring can be rolling guided smoothly relative to the trunnion by an inexpensive and simple construction while avoiding the offsetting of a shaft portion which supports the power roller.

Abstract: An axial bearing between a first part and a second part that presses with an axial load against the first part and can rotate around a rotation axis relative to the first part comprising a circular or arc-shaped ridge on the first part centered around the rotation axis, a pressure source for providing pressurized hydraulic fluid on a first side of the circular or arc-shaped ridge, an adjustable gap between the circular or arc shaped ridge and a bearing surface on the second part, wherein the pressurized hydraulic fluid flows through the adjustable gap to a second side of the circular or arc-shaped ridge. In accordance with the invention the circular or arc-shaped ridge or the bearing surface include a ridge chamber for locally creating a larger adjustable gap between the circular or arc-shaped ridge and the bearing surface.

Abstract: An axial plain bearing assembly includes a thrust ring provided for common rotation with a rotary component. The thrust ring has a radial seal face on an end face thereof for co-operating with a radial seal face of a non-rotational seal ring of a gas-lubricated mechanical face seal assembly for sealing said rotary and stationary components against each other. A plurality of peripherally spaced gas-pumping grooves is formed in at least one of the radial seal faces of the thrust and non-rotational seal rings. A mass ring connected with the thrust ring is provided at an axial distance from the thrust ring. The mass ring is configured and adapted to exert a balancing force on the thrust ring under centrifugal forces acting on the mass ring during common rotation of the mass and thrust rings to compensate for thermal distortion of the thrust ring during operation.

Abstract: A bearing sleeve 8 is press-fitted into a housing 7, and an axial portion 2a of an axial member 2 is inserted into the inner peripheral surface 8a of the bearing sleeve 8, and then a thrust member 10 is attached to the lower end of the inner peripheral surface 7c of the housing 7 and positioned in a predetermined position to fix it by ultrasonic welding. The lower end of the housing 7 is pressed against the outer peripheral surface of the thrust member 10 with applying ultrasonic vibration, to fix the melting junction surface of the housing 7 on the thrust member 10.

Abstract: In order to easily and inexpensively manufacture a shaft member provided with a flange, which is capable of stably yielding excellent bearing performance, a shaft member (2) is provided with a shaft portion (2a) and a flange portion (2b) coupled with a lower end surface (2a2) of the shaft portion (2a). The shaft portion (2a) is formed into a complete circular shape in cross section, and the flange portion (2b) is provided with a through-hole (2c) in which a part of a circumferential region is retracted to a radially outer side with respect to a lower end of the shaft portion (2a) so as to exhibit a non-circular shape. The shaft portion (2a) and the flange portion (2b) are coupled with each other in a state of butting the lower end surface (2a2) of the shaft portion (2a) and an upper end surface (2b1) of the flange portion (2b) against each other.

Abstract: A machine and method for a hydrostatic axial sliding bearing that has bearing and sealing functions and is capable of exhibiting reduced power losses. The hydrostatic axial sliding bearing of the machine is defined by axial sliding bearing surfaces that are separated by a fluid film and adapted for movement relative to each other during operation of the machine. The machine has first and second elements that define a first and a second of the axial sliding bearing surfaces. In combination, the first and second axial sliding bearing surfaces function as bearing and sealing surfaces for the hydrostatic axial sliding bearing. The machine is adapted so that the first and second axial sliding bearing surfaces move relative to each other in a first direction of motion, and at least the second axial sliding bearing surface has a surface profile with an oscillatory waveform in the first direction of motion.

Abstract: Hydrodynamic bearing assemblies and apparatuses are disclosed. Such hydrodynamic bearing assemblies may be employed in bearing apparatuses for use in downhole motors of a subterranean drilling system or other mechanical systems. In one embodiment of the present invention, a hydrodynamic bearing assembly includes a plurality of bearing segments distributed circumferentially about an axis. Each bearing segment includes a superhard bearing surface. The plurality of bearing segments define a plurality of seams. Each seam is formed between circumferentially-adjacent bearing segments of the plurality of bearing segments. Further embodiments of the present invention include hydrodynamic bearing apparatuses and downhole motors that may utilize any of the disclosed hydrodynamic bearing assemblies.

Abstract: According to the preferred embodiment of the present invention, a production method of a fluid dynamic bearing including: a shaft arranged along a center axis; an annular portion expanding radially outwards from the shaft; a sleeve having a top surface opposed to an under surface of the annular portion, for supporting the shaft and the annular portion in a relatively rotatable manner; and a lubricating fluid interposed between the shaft and annular portion and the sleeve, includes the step of preparing the annular portion having a substantially annular edge surrounding the center axis on the under surface; the step of applying a forming liquid for forming a solid lubricating film on the radially outer side of the edge of the under surface; and the step of evaporating a solvent of the forming liquid.

Abstract: A highly position-stabilized indexable table or “dial” in which the dial is supported relative to a steel surface on a frame by one or more air bearings. A flexure mechanically connects the indexing motor to the dial in such a way as to be torsionally non-compliant, but axially compliant to decouple the dial from the motor shaft along the Z-axis. In one embodiment, the air bearings are mounted to the frame at uniformly angularly displaced positions under the dial. In another embodiment, the bearings are partially integrated into the dial. Negative (suction) preload can be used in either embodiment to increase air bearing stiffness and/or to allow inverted processing; i.e., mounting part fixtures on an undersurface of the dial.

Abstract: A thrust bearing device comprising a runner portion attached to a rotational axis and having a plane perpendicular to the axial direction of the rotational axis, and a fixed portion having a sliding surface facing the plane of the runner portion, wherein the fixed portion has a plurality of oil grooves extending in radial directions formed on the sliding surface, a plurality of tapered lands formed among some of the plurality of oil grooves on the sliding surface and having a tapered plane and a plane, a plurality of flat parts formed among the remainder of the plurality of oil grooves on the sliding surface and having only a plane, and a plurality of oil supply openings formed in each of the plurality flat parts and pressurized oil is externally supplied.

Abstract: A thrust yoke is fixed into a second recessed portion of a base with adhesive. The second recessed portion has a first surface to be in contact with the bottom surface of the thrust yoke, and a second surface axially opposing the bottom surface of the thrust yoke with a gap therebetween. The thrust yoke has a bent portion at its radial end. The bent portion is bent downward. The thrust yoke also has a protruding portion extending downward from the bent portion. The protruding portion axially opposes the second surface of the second recessed portion of the base with a gap therebetween.

Abstract: A shaft, a circular plate portion and a cylindrical portion are integrally formed with one another through cutting operations to provide a rotor hub of a motor. An inner region on the lower surface of the circular plate portion is formed continuously with the outer peripheral surface of the shaft, and a hub thrust portion is provided in the inner portion so as to axially face a sleeve thrust portion on a sleeve main body. A stepped portion on the lower surface of the circular plate portion is disposed on the outer side of thrust dynamic pressure grooves on the sleeve thrust portion. In this manner, the stepped portion is disposed in a region where a thrust bearing portion is not provided, so that the hub thrust portion can be formed at a low cost in manufacturing the rotor hub by cutting.

Abstract: A blood pump apparatus comprises a housing, a centrifugal pump section including an impeller and rotating inside the housing to feed a fluid by a centrifugal force, an impeller rotational torque generation section for attracting thereto said impeller and rotating said impeller; and a plurality of grooves for hydrodynamic bearing provided on an inner surface of said housing at a side of said impeller rotational torque generation section, each of the grooves for hydrodynamic bearing having a first side and a second side both extending from a periphery of said portion in which a groove for hydrodynamic bearing is formed toward a central side thereof and opposed to each other, a third side connecting one end of said first side and one end of said second side to each other, and a fourth side connecting said other end of said first side and said other end of said second side to each other; said first side and said second side are formed as a circular arc respectively in such a way that centers of said circular arcs

Abstract: A plate-like material is pressed and a middle concave portion centered on a center axis is formed in one axial surface of the material. Likely, an annular concave portion centered on a center axis and radially outwardly arranged is formed in one and/or the other axial surface of the material. The material is then cut along a radially outer rim of the middle concave portion, and between a radially outer rim and a radially inner rim of the annular concave portion. In this way, a thrust plate having indented portions at radially inside and outside portion of the one and/or the other axial surface thereof is manufactured. A burr formed in press working is accommodate within the indented portion and does not axially protrude from the one and/or the other axial surface of the thrust plate.

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 fluid dynamic bearing is constructed to support stably a rotating body to which a non-uniform force is applied, and a hard disk drive (HDD) employing the fluid dynamic bearing is provided. The fluid dynamic bearing includes a journal bearing part supporting a rotary shaft in a radial direction of the rotary shaft, a thrust part formed at one end of the rotary shaft, a thrust bearing part facing the thrust part and supporting the rotary shaft in a longitudinal direction of the rotary shaft, and a plurality of grooves formed on a surface of the thrust bearing part and/or the thrust part. The plurality of grooves include a first groove group including a plurality of grooves having the same shape and arrangement, and a second groove group adjacent to the first groove group and including at least one groove asymmetric with respect to the grooves of the first groove group.

Abstract: A hydrodynamic bearing set, for use with a thrust disk disposed between planar surfaces of a housing, includes first and second topfoils disposed adjacent first and second thrust disk axial bearing surfaces and removably secured to the housing. An underspring is secured between each planar housing surface and the corresponding topfoil. Dual-leaf spring pairs attached to at least one topfoil periphery function to urge the topfoils away from the thrust disk axial bearing surfaces by applying a force against a planar housing surface, another topfoil, or a spacer washer secured between adjacent topfoil dual-leaf pairs or frictionally retained within the housing. Alternatively, a wavy washer, a conical spring, a Belleville washer, or a coil spring can be substituted for the dual-leaf spring pairs.

Abstract: A hydrodynamic bearing device which realizes power saving, reduction of a time period necessary for stabilizing rotation, and enhancement in durability to startup and halting of the motor at the same time by accelerating circulation of a lubricant in the vicinity of a flange with torque loss being kept low is provided. A flange (3) is fixed to one end of a shaft (2). On an inner surface of one of openings of a sleeve (1), a step portion (1C) is provided. When the shaft (2) is inserted into the sleeve (1), the flange (3) is in close vicinity to the step portion (1C). An inner diameter of the step portion (1C) is smaller in end portions in an axial direction than in a central portion. Thus, a gap between an outer surface (3C) of the flange (3) and a surface of the step portion (1C) which opposes the outer surface (3C) is narrow in the vicinity of boundaries of the outer surface (3C) of the flange (3) than in the vicinity the central portion.

Abstract: A hydrodynamic plain bearing is provided and includes a raceway which is rotatable about an axis of rotation and which is mounted in the axial direction on a plurality of carrying segments (12). A lubricating oil film is formed between the raceway and the carrying segments (12) in a bearing gap. In such a plain bearing, a circulation of the lubricating oil is brought about in a simple way in that the plain bearing is equipped with an integrated pumping device (15) for pumping the lubricating oil around in a circuit.

Abstract: A thrust bearing assembly comprising a bearing runner and a bearing carrier, the carrier defining a plurality of thrust pad sites annularly around the carrier, with a thrust pad disposed at a site and with the carrier limiting movement of the thrust pad in a direction generally radial to the longitudinal axis of the runner while allowing the thrust pad to move in a direction generally parallel to the longitudinal axis. Though the range of movement is limited, the pads can tilt under load to form a hydrodynamic wedge as is known in the art. An embodiment comprises a bearing runner having a wear resistant face and a bearing carrier defining thrust pad sites disposed annularly around the carrier. In one implementation, at each site, a deflection element (e.g., Belleville washer) is disposed in a cavity and a pad is disposed over the deflection element. The pad can be at least partially disposed within the cavity. The wear resistant face contacts the pad.

Abstract: The present invention aims to improve the efficiency of a clamping step for combining a flange with a shaft and to improve productivity. The shaft and the flange are tentatively combined in the tentative clamping step. In the tentative clamping step, a concave part at the end of the shaft is pressurized by a metal mold such as a ball to be enlarged in an outer circumferential direction, thereby pressurizing this concave part against the inner circumference of the flange so as to fix the concave part. The combined body made by tentatively combining the shaft and the flange is strongly combined in a proper clamping step. In order to correct a distortion such as a warpage of the flange that has been solidly combined by the proper clamping step, sandwiching the flange by the upper and lower metals, the flange is pressurized and a flash molding is carried out.

Abstract: A fluid dynamic pressure effect can be sufficient without receiving a large effect of viscous friction of lubricating oil with changes in the environmental temperature in which it is used, and smooth starting of the rotating shaft can be ensured by regulating the gap between the rotating shaft and bearing within a suitable range. An outer diameter of the bearing, D, a length in an axial direction of the bearing, L, a gap at a radial side which is between the rotating shaft and the bearing, C, and an inclining height of the bearing end surface to which the flange is faced, ?, satisfy the expression L/D<C/?. It is preferable that the inclining height, ?, be 2 to 6 ?m, the inner diameter of the bearing be 1 to 3 ?m, and the gap at a radial side, C, be 1 to 4 ?m.

Abstract: The hydrodynamic bearing device comprises a sleeve 1, a shaft 2, a thrust bearing portion, and a lubricating fluid 5. The sleeve 1 has a bearing hole 1C. The shaft 2 is inserted into the bearing hole 1C in a state of being able to rotate relative to the sleeve 1. The thrust bearing portion has a hydrodynamic groove for generating pressure in the axial direction. The lubricating fluid 5 is held in a gap formed by the thrust bearing portion. The hydrodynamic bearing device is further constituted so that the value of a wear amount function F6 falls into a specific range. With the hydrodynamic bearing device, the required bearing performance can be satisfied, and the thrust bearing portion has a longer intermittent service life.

Abstract: A hydrodynamic bearing device is provided for use with a spindle motor. The hydrodynamic bearing device has a sleeve made of a sintered metal that is obtained by sintering a sintering material that is iron, an iron alloy, copper, a copper alloy or a mixture thereof. This sintered metal has independent pores, which do not communicate with each other, by selecting conditions for forming a desired sintered body within a predetermined range. The conditions includes a grain size of powdered metal of a material for the sintered metal, a molding pressure when the molded body is formed, sintering temperature and sintering period in the sintering step.

Abstract: A thrust plate used in a fluid dynamic pressure bearing of the present invention includes a concave portion in which a lower end portion of a shaft is accommodated. The thrust plate is immersed in a lubricant, and is disposed between the lower end portion of the shaft and a bottom-portion upper surface of a bearing housing without being fixed to the bearing housing. Accordingly, the thrust plate radially moves in accordance with the position in which the lower end portion of the shaft is in contact with the concave portion of the thrust plate. As a result, the centers of the shaft and the thrust plate motor can be aligned satisfactorily.

Abstract: One embodiment of a hybrid vertical axis rotating load carrying bearing with continuously variable operating conditions able to carry surprisingly heavy weight, and occasionally easily able to carry drastically more weight than that; The preferred embodiment has 3 different types of bearings combined to form one ideal bearing. The first type of bearing is a half ball and female sliding bearing. The second type of bearing is a floating bearing that surrounds the sliding bearing. The third type of bearing is rolling bearings. In this preferred embodiment with 3 different types of bearings, the rolling bearings are partially engaged under ideal load weight conditions, and nearly fully engaged under severe load weight conditions. The sliding and floating bearings are always fully engaged into the vertical weight load no matter what the vertical weight load may be. Another embodiment is the hybrid bearing containing two types of bearings; a floating bearing and rolling bearings.

Abstract: There are provided a thrust plate with which there is less warpage when the thrust plate has been incorporated into a hydrodynamic bearing device, which improves the reliability of the hydrodynamic bearing device, as well as a hydrodynamic bearing device, a spindle motor, and an information apparatus equipped with this thrust plate, and a method for manufacturing a thrust plate. With a thrust plate that is provided at one end of a shaft of a hydrodynamic bearing device and that closes off one end of a sleeve formed so as to surround the shaft via a lubricating fluid (oil), a laser irradiated portion is provided to the opposite side of the thrust plate from the side facing the shaft in order to reduce the warpage that is produced by the formation of a hydrodynamic groove on the side facing the shaft, and the warpage that occurs during assembly, etc.

Abstract: An axial thrust bearing for axially supporting a rotating shaft of an exhaust gas turbocharger connected to a lubricating oil circuit includes a profiled annular bearing surface which contacts an essentially flat sliding surface, the bearing surface having a plurality of radially extending grooves which are open on the outside circumference, a plurality of coplanar flat trap surfaces located between respective pairs of adjacent grooves, and a plurality of wedge surfaces located between adjacent pairs of respective grooves. Each wedge surface forms a lubricating oil gap which narrows circumferentially toward an adjacent flat trap surface and which narrows radially toward the outside circumference.

Abstract: An exemplary center housing for a turbocharger includes a bore for supporting a turbocharger shaft, a lubricant feed port, a first lubricant outlet port, a second lubricant outlet port and a valve operably disposed to provide a first path from the lubricant feed port to the first lubricant outlet port and a second path from the lubricant feed port to the second lubricant outlet port wherein the valve responds to pressure generated by axial movement of the turbocharger shaft to increase resistance of the first path or the second path. Various other exemplary mechanisms are also disclosed.

Abstract: A flange on a shaft of a fluid dynamic bearing unit is to be provided with a hole connecting an outer periphery of the flange and an outer periphery of the shaft. A radial groove is provided on a surface of two flange half pieces, and a vertical groove communicating with the radial groove is provided on an inner circumferential surface of the flange half pieces. Upon combining the two flange half pieces with the grooves facing each other and attaching them to the shaft, a path connecting an outer periphery of the flange and an outer periphery of the shaft is formed. The groove may be formed in a desired cross-sectional shape such as a semicircle, triangle or rectangle. The groove may be formed only on either of the flange half pieces, and the groove can be formed by a simple process such as pressing.

Abstract: A fluid dynamic bearing motor including a stationary sleeve, a rotating shaft axially disposed through the sleeve, a journal gap between the shaft and the sleeve, the gap defined by first and second interfacial surfaces of the shaft and sleeve, at least one set of fluid dynamic grooves formed on the first interfacial surface of the journal gap, and at least one step defined on the second interfacial surface of the journal gap.

Abstract: An exemplary thrust collar for a turbocharger includes a substantially annular body that includes an axis of rotation, a bore, opposing end surfaces where one of the end surfaces is substantially normal to the axis of rotation and capable of seating a back end of compressor wheel, and a surface disposed in the bore where the surface is substantially normal to the axis of rotation and capable of seating a surface of a turbocharger shaft. The axial distance between the end surface for seating a back end of a compressor wheel and the surface disposed in the bore for seating a surface of a turbocharger shaft is selected to improve balancing of a rotating assembly. Various other exemplary devices, systems, methods, etc., are also disclosed.

Abstract: Thrust cam (1) for a gear wheel transmission (17), characterized in that it is at least made of two separate parts (2,3) which can move in relation to each other.

Abstract: A plate-like material is pressed and a middle concave portion centered on a center axis is formed in one axial surface of the material. Likely, an annular concave portion centered on a center axis and radially outwardly arranged is formed in one and/or the other axial surface of the material. The material is then cut along a radially outer rim of the middle concave portion, and between a radially outer rim and a radially inner rim of the annular concave portion. In this way, a thrust plate having indented portions at radially inside and outside portion of the one and/or the other axial surface thereof is manufactured. A burr formed in press working is accommodate within the indented portion and does not axially protrude from the one and/or the other axial surface of the thrust plate.

Abstract: A device for changing the control times of an internal combustion engine (camshaft adjuster (1)) having a pressure medium distributor (21) arranged within a camshaft (11) is provided. The pressure medium distributor (21) is provided at its front end with a radially extending shoulder (42), this shoulder (42) forming part of the camshaft axial mounting.

Abstract: A thrust bearing assembly including a flexible thrust washer sandwiched between first and second races. The thrust washer includes notches between adjacent support regions. When a thrust load is applied to the bearing assembly, the thrust washer elastically flexes at the notched or unsupported regions and creates undulations in the washer's dynamic surface to create an initial hydrodynamic fluid wedge with respect to the corresponding dynamic surface of the second race. The gradually converging geometry created by these undulations promotes a strong hydrodynamic action that wedges a lubricant film of a predictable magnitude into the dynamic interface between the thrust washer and the second race in response to relative rotation. This lubricant film physically separates the dynamic surfaces of the thrust washer and second race from each other, thus minimizing asperity contact, and reducing friction, wear and bearing-generated heat, while permitting operation at higher load and speed combinations.

Abstract: A high-accuracy, long-life hydrodynamic bearing that does not cause oil film breakage in bearing clearances and a disc rotation apparatus using the bearing is disclosed. Oil film breakage is avoided as negative pressure is prevented from generating between the shaft and sleeve of the hydrodynamic bearing. Herringbone shaped dynamic pressure generating grooves, located on the thrust bearing section and the radial bearing section of the hydrodynamic bearing, are oil filled and have optimum shapes. The optimum shapes prevent the generation negative pressure and thus prevents the coagulation of air bubbles that can cause oil film breakage. The disc rotation apparatus, that holds a reproduction/recording disc, is concentrically secured to the hydrodynamic bearing and rotated. The disc is put into contact with magnetic or optical heads while rotating in the disc rotation apparatus. Both the hydrodynamic bearing and the disc rotation apparatus experience high reliability.

Abstract: A high-accuracy, long-life hydrodynamic bearing that does not cause oil film breakage in bearing clearances and a disc rotation apparatus using the bearing is disclosed. Oil film breakage is avoided as negative pressure is prevented from generating between the shaft and sleeve of the hydrodynamic bearing. Herringbone shaped dynamic pressure generating grooves, located on the thrust bearing section and the radial bearing section of the hydrodynamic bearing, are oil filled and have optimum shapes. The optimum shapes prevent the generation negative pressure and thus prevents the coagulation of air bubbles that can cause oil film breakage. The disc rotation apparatus, that holds a reproduction/recording disc, is concentrically secured to the hydrodynamic bearing and rotated. The disc is put into contact with magnetic or optical heads while rotating in the disc rotation apparatus. Both the hydrodynamic bearing and the disc rotation apparatus experience high reliability.

Abstract: A turbomachine has a rotor shaft, which is mounted in a bearing arrangement containing a hydrodynamic axial bearing, and a rotor disposed on the rotor shaft. A hydrostatic axial bearing is additionally provided in the immediate vicinity of the hydrodynamic axial bearing, the hydrostatic axial bearing absorbing the axial force acting on the rotor shaft at rest, completely or at least for the most part, relieving stress on the hydrodynamic axial bearing during start-up processes of the rotor shaft, and being shut off during operation at the rated speed of rotation.

Abstract: A hydrodynamic bearing having an improved air discharging path for discharging air from the bearing when a shaft is inserted into the bearing, and an apparatus for driving a polygonal mirror using the hydrodynamic bearing.