Showing papers on "Thrust bearing published in 1990"

Axially stabilized magnetic bearing having a permanently magnetized radial bearing

Abstract: A magnetic bearing arrangement for a rotor, having permanent magnets to absorb radial bearing forces, and having an axial stabilizer which keeps the rotor in a contactless position in relation to the stator. Attached to the stator are electric coils, which interact with magnetizable parts fastened to the rotor. To make the bearing arrangement as independent as possible from the spatial orientation of the rotor axis, and from housing deformations, there is provided, in the vicinity of the rotor center of gravity, a center-of-gravity bearing having a comparatively high radial rigidity and at another point of the rotor there is provided a stabilizer bearing, having a radial rigidity which is less than that of the center-of-gravity bearing. The center-of-gravity bearing supports the major portion of the rotor weight, and the stabilizer bearing is primarily responsible for the static and dynamic stabilization of the entire system.

Dynamic pressure bearing device

Abstract: A dynamic pressure bearing device includes a sleeve and a shaft member which is rotatably fitted into the sleeve. The sleeve is made of an aluminum alloy containing a carbon fiber and has a radial bearing surface formed in an inner peripheral surface and a thrust bearing surface formed in a lower end surface. The shaft member includes a base portion having a thrust receiving surface formed on an upper surface, and a shaft portion extending upright from the base portion and having a radial receiving surface formed on an outer peripheral surface. A first dynamic pressure generating groove is formed in at least one of the radial bearing surface and the radial receiving surface, and a second dynamic pressure generating groove is formed in at least one of the thrust bearing surface and the thrust receiving surface. The shaft member including the shaft portion and the base portion is molded from a synthetic resin as a unitary body. The thrust bearing surface is tapered so that a thrust bearing gap formed between the thrust bearing surface and the thrust receiving surface increases gradually, radially and outwardly.

Magnetic bearings for pumps, compressors and other rotating machinery

Abstract: A rotating machine having a rotor comprising a flexible shaft with a plurality of masses distributed along the shaft. Included within these masses are magnetic disks. Magnetic bearings are attached to the housing and coact to support the rotor in only a radial direction or in both radial and axial directions. Bearing sensors are used to measure the shaft position local to each bearing relative to a face of each bearing. Variable magnetic bearing parameters are controlled so as to change values of stiffness and damping of the magnetic bearings in response to the measurements from the bearing sensors. These controls can be direct analog circuitry, or digital components, or a combination of digital and analog components.

Method and apparatus for providing torque converter having improved stator/clutch assembly

Abstract: A method of manufactore of, and apparatus for, a torque converter assembly having an improved reactor assembly. A torque converter is disclosed having a stator which has improved and simplified casting and machining requirements. A stator hub is provided having a cylindrical bore substantially coaxial with the axis of the transmission shaft to which the torque converter is mounted. An overrunning clutch and thrust bearing cartridge assembly is provided to be fitted into the stator hub bore. The overrunning clutch provides improved lubrication on both sides of the clutch engaging element surfaces, either rollers or sprags, between the inner and outer rings which form the clutch races. Wear surfaces within the clutch assembly are stamped steel instead of aluminum. Clutch load is increased by increasing the roller or sprag dimensions in the direction of the stator axis, while maintaining the same stator hub width. Thrust bearings are mounted to the outside of the overrunning clutch.

Turbocharger bearing assembly

Abstract: An improved bearing assembly is provided for axially retaining journal bearings (14,15) in a turbocharger (10). The turbocharger (10) includes a center housing (24) having an elongated bearing bore (28) for receiving an axially spaced pair of journal bearings (14,15) which in turn support a rotatable turbocharger shaft (12). Lubricating oil is supplied through the center housing (24) for passage to the shaft-bearing interface through radially open oil flow ports (36,37) formed in the journal bearings (14,15). A bearing spacer (42) is interposed axially between the journal bearings (14,15) such that the opposite ends of the bearing spacer (42) define a pair of thrust surfaces (52,54) for engaging and locating the axially inboard faces of the journal bearings (14,15). Additional thrust surfaces are formed on thrust members carried by the turbocharger shaft (12) to engage and locate the axially outboard faces of the journal bearings (14,15). The outer diameters of these thrust surfaces are less than the outer diameter of the journal bearings (14,15) to promote substantially unimpeded, axially bidirectional oil flow over and about the journal bearings (14,15).

Dynamic pressure type fluid bearing apparatus

Abstract: A dynamic pressure type fluid bearing device includes: a shaft; a sleeve into which the shaft is fitted to be rotatable relative to the shaft; two dynamic pressure generating grooves provided on either peripheral surface of the shaft or the inner peripheral surface of the sleeve; and a lubricant held between the shaft and the sleeve. The device has a void, enclosing air, interposed between the two dynamic pressure generating grooves, wherein each of the dynamic pressure generating grooves is not less than four microns in depth and makes an acute angle of less than 20° with a rotational direction of the shaft or the sleeve. The fluid bearing device can include: a sleeve; a shaft fitted into the sleeve, one end surface of which is in contact with a thrust bearing fixed to the sleeve; a dynamic pressure generating groove provided on either the inner peripheral surface of the sleeve or the peripheral surface of the shaft; and a lubricant provided to enclose a space between the shaft and the sleeve as well as the thrust bearing, wherein the dynamic pressure generating groove is not less than four microns in depth and makes an acute angle of less than 17° with a rotational direction of the shaft or the sleeve.

Gas dynamic bearing for spindle motor

Abstract: A spindle motor comprising a stator including a support shaft positioned on a base, a cap-shaped rotor rotatably and concentrically disposed around the support shaft, thrust and radial bearings disposed between the stator and the rotor, a stator coil secured to the stator, and a rotor magnet member secured to the rotor opposing the stator coil. The thrust and radial bearings are hydrodynamic bearings. A movable piece that constitutes a part of the thrust bearing is secured to the lower end of a cylindrical portion of the rotor and extended outwardly or inwardly from the cylindrical portion, or is disposed above the rotor. The stator coil is secured to the outer peripheral portion of the support shaft above or below the radial bearing. The rotor magnet member is securd to the inner peripheral surface or inner top surface of the rotor. Either a radial or axial gap is provided between the stator coil and the rotor magnet member.

Auxiliary bearing design for active magnetic bearings

Abstract: A magnetic bearing rotating structure includes a rotor magnetically supported in a housing by a magnetic bearing. A back-up bearing arrangement is used to resist impact on the rotor, including a fixed bumper bearing for resisting a sudden impact, and an auxiliary bearing for rotatably supporting the rotor while the magnetic bearing resumes operation.

Bearing structure for downhole motors

Abstract: A bearing assembly for a downhole motor comprising a pair of annular support rings, each having a plurality of polycrystalline diamond thrust bearing inserts mounted thereon. The rings are oriented to have the respective inserts face and bear against each other. In operation, drilling mud passes through the space between the inserts to cool the inserts. The rings are made of tungsten carbide to prevent erosion of the areas at the bases of the inserts, thereby improving the life of the thrust bearings.

Earth boring bit with recessed roller bearing

Abstract: A roller cutter earth boring bit having longer roller bearings recessed into surrounding bit structure for increased load carrying capacity. The elimination of thrust bearing shoulders from the bearing pin structure between sets of roller bearings enables the use of such longer roller bearings.

Two-stage submersible propulsor unit for water vehicles

Abstract: A two-stage submersible propulsor unit comprises a shroud having a water inlet and a water outlet, a shaft assembly centrally mounted within the shroud, an upstream and a downstream propeller, each of which includes a separate hub rotatably mounted on the shaft assembly, first and second electric motors separately rotating the upstream and the downstream propellers. Each motor includes a rotor mounted around the outer periphery of one of the propellers and a stator mounted around the shroud, and first and second thrust bearing assemblies for absorbing the thrust load generated between the hubs of the first and second propellers and the shaft assembly. Both thrust bearing assemblies are contained within a housing located on the downstream end of the shaft assembly. The shaft assembly includes a stationary outer shaft where the first and the second propellers are rotatably mounted, and a rotatable inner shaft which is connected to the hub of the upstream propeller for transferring thrust from the upstream propeller to the first thrust bearing assembly located in the downstream end of the shaft assembly. The foregoing arrangement advantageously avoids positioning a thrust bearing assembly in front of the upstream propeller which in turn would interfere with the smooth flow of water into the unit, and create noise.

Lubricant system for a rotary cone rock bit

Abstract: A radially disposed thrust bearing surface formed in a rotary cone is provided with at least a pair of grooves and a ramp surface on the trailing edge of the grooves. The groove provides a lubricant reservoir and the ramp serves to generate hydrodynamic pressures during rotation of the rotary cone on the thrust surface of a journal bearing thereby distributing a film of lubricant on the opposing thrust bearing surfaces.

Plastics housing thrust bearing with complete sealing

Abstract: A thrust ball bearing (10) for a McPherson strut provides rubbing seals that are integral with rigid plastics housings by making a pair of sealing flanges (38,40) on an upper housing (20) flexible enough to continuously engage a pair of sloped seal surfaces (26,28) on a lower housing (18).

Low flow tilting pad thrust bearing

Abstract: The bearing pads of a hydrodynamic tilting pad thrust bearing are cut from a ring and arranged in a circle within a retainer (30) for bearing the load of a collar fastened to a rotating shaft. The leading and trailing edges of respective adjacent pads contain open edge grooves (19) which together form a pocket for receiving and dispensing lubricating and cooling oil under controlled conditions. Semicircular grooves (16,17) in the edges of the adjacent pads together form generally circular ducts through which the oil is conducted to the pockets.

Tapping attachment for a punch press

Abstract: A tapping attachment (1) for threading a relatively large number of holes through a sheet metal part at a relatively low cost per hole The tapping attachment includes a thrust bearing assembly (6) which is aligned with a turret-type punch press or the like and movable in response to an axially directed force generated by the punch press The axially directed force applied from the press to the thrust bearing assembly is transferred to a spline shaft (26) The spline shaft is rotated within and moved linearly relative to a screw threaded roller nut (74), whereby the axially directed force is converted into a rotating force for advancing and turning a tap (80) at high speeds of rotation A nitrogen reservoir (14) is provided so that a supply of gas is available for returning the thrust bearing assembly and the spline shaft to their initial positions in order that a new hole can be tapped in response to another axially directed force Also provided is an oil reservoir (12) so that a supply of oil is available for lubricating and cooling the tap via an oil spout

Fixed swash plate for an axial piston machine

Abstract: A fixed swash plate for an axial piston machine of fixed capacitive type, which has a casing housing therein a cylinder, is formed to have its divided surfaces on the horizontal plane along the axis of the rotary shaft of the cylinder, wherein a support member constituting a fixed swash plate is formed to be easy to produce and the casings merely sandwich therebetween the support member, whereby a thrust bearing constituting the fixed swash plate is held in the state of being slanted at a predetermined angle other than 90° with respect to the axis of rotary shaft. Also, the rotation direction of the fixed capacitive type axial piston machine is easy to change by inverting at an angle of 180° the assembling direction of support member constituting the fixed swash plate.

Loading cam mechanism for toroidal type continuously variable transmission

Abstract: In a toroidal type continuously variable transmission having a center shaft, input and output discs mounted on the center shaft, friction rollers confined in a toroidal cavity formed between the input and output discs, and a loading cam mechanism for applying an axial thrust load on the input disc in accordance with an input torque, there is provided an annular oil receiving member which forms an annular oil reservoir around the center shaft for collecting a lubricating oil discharged from a hole of the center shaft, and storing the oil so as to immerse cam rollers and/or a thrust bearing of the loading cam mechanism.

Hydrostatic spindle device

Abstract: A hydrostatic spindle device has a housing, a hydrostatic radial bearing at each end of the housing, a spindle rotatably and translatably supported by the hydrostatic radial bearings, and extending through the bearings. A hydraulic motor is attached to one end of the spindle and a cutting tool or workpiece is attached to the other end. The interior of the housing comprises a cylinder in which a piston, fashioned integral with the spindle travels. Pressurized hydraulic fluid suitably introduced by an electrohydraulic servo control system precisely controls the translational position, velocity, and acceleration of the spindle. Hydrostatic thrust bearings at each end of the cylinder prevent the piston, when rotating, from wearing either end surface of the cylinder.

Thrust bearing system for counter-rotating propeller shafts, particularly ships propeller shafts

Abstract: Two propeller shafts are disposed coaxially one within another. A collar of the inner propeller shaft grips into the hollow outer propeller and supports the inner shaft axially over axial friction bearing elements. The axial friction bearing elements are surrounded by a shaft connecting piece, which is divided in the axial direction and at least one half of which can be removed radially, in order to create access to the axial friction bearing elements. By way of the axial friction bearing elements, axial forces of the inner propeller shaft reach the hollow outer propeller shaft and, from the latter, by way of further axial friction bearing elements, further reach a bearing housing, which is preferably also divided in the longitudinal direction.

On the Significance of the Inlet Pressure Build-Up in the Design of Tilting-Pad Bearings

Abstract: An operating tilting-pad thrust bearing generates a fore-region which is responsible for maintaining, at the bearing entrance, a pressure which is higher than the ambient pressure. This entrance pressure, in the presented analysis, is obtained by applying to the fore-region the momentum integral theorem. The solution of the lubricating film region is then obtained by using this modified inlet pressure. This solution yields the pressure distribution, the load carrying capacity, the film ratio and the frictional force for several values of the modified Reynolds number and various pivot positions

Motor-driven foldable type door mirror

Abstract: In a motor-driven foldable type door mirror using two stages of worm gears as reduction gear mechanism, an idle gear is interposed between a gear at a reduction gear and a gear of a clutch mechanism to provide a larger reduction ratio and for no interference of the second-stage worm gear with the assembling of the clutch mechanism. Also, to minimize the abrasion, caused by a thrust load developed at the second-stage worm, of both ends of the rotating shaft of the second-stage worm as well as of the thrust bearings which bear both the ends of the rotating shaft, balls for the thrust bearings are interposed between both the ends of the second-stage worm and the thrust bearings.

Variable displacement compressor with shaft end play compensation

Abstract: A variable displacement compressor having a rotary drive shaft coupled to a gas pressure positioned wobble plate carried by a drive mechanism including a drive journal and journal sleeve on the rotary drive shaft and a drive lug connected to the drive shaft having a slot operatively connected by a coupling pin to the journal. Thrust bearings located in the cylinder head and front head of the compressor axially position the drive mechanism within a gas pressured crankcase. The rear thrust bearing includes a race engaged by a coil spring on the shaft to provide relative axial movement between the shaft and the rear thrust bearing to compensate for end play between the thrust shoulders and the thrust bearings following assembly of the cylinder head and front head. The coil spring has a first predetermined biasing force when the wobble plate is in a full stroke position to maintain a minimum spring load on the thrust bearings to reduce wear during operation of the compressor at high air conditioning loads and the coil spring is shifted into a compressed position to provide an increased load on the thrust bearings in a direction to resist load reversals on the shaft when the compressor is operating under low air conditioning load conditions.

Submersible thrust bearing apparatus

Abstract: A thrust bearing including a ring-like form plate body, and a plurality of rib members provided on the ring-like form plate body of the thrust bearing. Such a plurality of rib members may be provided on a thrust runner. The rib members cause a difference in load deformation amount in a circumferential direction according to thrust load and generate a wedge-shaped form clearance between a sliding face of the thrust bearing and a sliding face of the thrust runner. Since the wedge-shaped form clearance is formed by utilizing the load deformation, even when the thrust load becomes large, the wedge-shaped form clearance does not become narrow. The occurrence of dynamic pressure by the wedge effect and the formation of a water film can be assured, and the temperature increase between the sliding face of the thrust runner and the sliding face of the thrust bearing can be restrained.

Thrust bearing with spiral grooved face

Abstract: A thrust bearing having a spiral element and a flat element is provided wherein bothy elements are arranged so as to be rotatable relative to each other and the spiral element is made of ceramic having a pattern of spiral grooves on the surface thereof opposing the flat element. The spiral grooves are formed by a shot-blasting process applied through a resin mask having a spiral pattern, the depth of the grooves being kept within the range between 3 μm and 50 μm.

Self-regulating lubricant supply for thrust bearings

Abstract: In a rotating shaft machine, the rotating shaft is usually equipped with a thrust collar which cooperates with stationary thrust bearings on either side of the thrust collar to prevent excessive axial movement of the rotating shaft. Lubrication is furnished to each bearing to protect the bearing as the shaft migrates toward that bearing. Prior art lubrication systems provided either equal amounts of lubrication fluid to equal sized bearings or a lesser amount of lubrication fluid to a smaller thrust bearing. It has been discovered that the total flow requirement for lubrication fluid can be reduced by using a lubrication fluid distribution means which tracks the position of the thrust collar and provides lubrication in response to the position of the thrust collar relative to the thrust bearings.

Power supply unit for a vacuum pump with magnetic thrust bearings and with an auxiliary power supply for the thrust bearings in case of a power failure

Abstract: Power supply system for a vacuum pump (1) comprising a rotor supported by magnetic bearings (3) and driven by an electronic motor whose rotor, integral with the rotor of the pump, is of the type comprising magnetic poles, the stator (2) of the electric drive motor, as well as the magnetic bearings (3) being powered by the mains (10), by way of electronic power circuits (7, 11) and control circuits (4, 6, 12), characterised in that it further comprises an auxiliary power circuit (14) whose output is connected to the circuit for powering the said magnetic bearings and which receives as input its energy supply, by way of a switch (15) closing automatically in the event of a mains power failure, the said drive motor operating as an alternator.

Bearing mounting arrangement for a lift mast

Abstract: A bearing mounting arrangement for a lift mast assembly has a retaining device which maintains a bearing member from movement relative to a first member of a lift mast assembly and directs a flow of lubricant past a second surface of the bearing member and into a groove opening at a first surface in the bearing member. The retaining device includes an elongated retaining member disposed in an aperture in the bearing member and the first member. The retaining device forcibly engages the bearing member and aligns the apertures in the bearing and first members. The bearing mounting arrangement is particularly useful for mounting a lift mast assembly on a material handling vehicle and a thrust bearing member on a side shaft carriage.

Bearing cooling system in horizontal shaft water turbine generator

Abstract: A bearing cooling system for a water turbine having a rotatable shaft connected at one end to a movable blade portion and supported by a journal bearing and by a thrust bearing having a collar, comprises a heat pipe including a first container surrounding and spaced from the rotatable shaft and extending axially from a predetermined engaging position adjacent the one end of the shaft to the journal and thrust bearings. The thrust bearing engages the outer surface of the first container, and the shaft and thrust bearing and inner surface of the container define walls of a sealed first chamber surrounding a portion of the rotatable shaft and communicating with the journal and thrust bearings. The system is adapted to include a fluid contained in the first chamber for absorbing heat generated by the journal and thrust bearings. A second container is spaced from and surrounds a portion of the first container adjacent the one end of the shaft. The first and second container together define a second chamber for receiving and containing flowing water from the turbine for cooling the fluid in the first chamber.

Magnetically driven pump

Abstract: of EP0431332The invention relates to a magnetically driven pump so designed that a drive power of an electric motor (15) is transmitted from a magnets-embedded drive rotor (16) to a magnets-embedded follower rotor (14) opposed to one another by way of a magnetic coupling, the follower rotor (14) and an impeller (5) being secured respectively to the opposite ends of a rotating shaft (4) to which a thrust bearing (3b) of ceramic material is fastened for receiving an axial load. A cushioning member (7), for example, a dish-shaped plate spring, is mounted on the rotating shaft (4), so as to push the thrust bearing (3b) from the rear, in the position between the thrust bearing (3b) and a flange (6) provided on the rotating shaft (4) for determining the position of the follower rotor (14).

Rotary supporting portion

Abstract: PURPOSE:To improve durability and reliability of a rotary supporting portion of various kinds by forming the inner circumferential portion of a race attached to a thrust bearing as an inner extended portion and approaching one portion of the inner extended portion to one end of a radial bearing. CONSTITUTION:The inner circumferential portion of a race 12 is extended inward the inner circumferential edge of a holder 10 constructing a thrust bearing 7 to be an inner extended portion 7. The press portion 19 of the inner extended portion 17 is approached to the end edge of a holder 8 constructing a radial bearing 6 so as to prevent the holder 8 from moving toward the fitting portion of the thrust bearing 7. Thus, durability and reliability of a rotary supporting portion of various kinds can be improved.