Showing papers on "Thrust bearing published in 1993"

Diamond bearing assembly

Abstract: The invention concerns a diamond bearing assembly for a downhole motor. The assembly (10) includes at least one set of opposing, relatively rotating thrust bearing rings (20, 22) each of which includes an annular support element (24, 30) and PCD compacts (26, 32) carried by the support elements. The PCD compacts of the bearing rings oppose one another at a thrust bearing interface (80). Shear limiting means (96, 110) are provided. These means are arranged to shear if frictional forces between the opposing PCD compacts at the thrust bearing interface exceed a critical level. This eliminates relative rotation between the bearing rings and avoids possible overheating and thermal degradation of the PCD. The shear limiting means can also serve as an alignment means to ensure correct axial alignment of the bearing components. The bearing assembly may also include a compact radial bearing capability.

Finite element analysis of grooved gas thrust bearings and grooved gas face seals

Abstract: A finite element method enabling the Reynolds equation solution for any face geometry of gas thrust bearing or of gas seal is presented. Difficulties due to thickness discontinuities are reduced by integration by parts of the terms involving derivatives. The weak form of the finite element Reynolds equation is then solved and the nonlinearity of the equation leads to the use of Newton-Raphson procedure. The process is fast convergent. The problem of oscillating solution is solved by the use of an upwind procedure. Some numerical examples show the accuracy and efficiency of the procedures. It is shown that the developed finite element program provides a numerical tool, more efficient than the method used until now, for the grooved gas seals design. 16 refs.

Magnetic bearing back-up

Abstract: A back-up bearing (50, FIG. 1) is provided for a magnetic journal or thrust bearing by a source of pressurized fluid 52 (such as gas), channels 51 supplying the fluid to the suspension gap 30 between moving bearing armature 25 and stationary armature pole faces 28 1 , 29 1 , and magnet control means 56 responsive to a decrease in gap width at any point below an acceptable minimum to supply the fluid by way of the channel(s) to the gap to form a hydrostatic bearing between stationary and movable armatures to aid or replace the magnetic bearing support. In a journal bearing, (FIG. 3) in which coil-containing spaces (62) exist between radially extending armature limbs the spaces may be closed by an apertured bridging piece (64) extending between pole faces and fluid supplied via that space to provide both increased hydrostatic bearing area and a way of cooling the coil by a low pressure fluid bleed at all times. The armatures faces may be provided with low friction bearing material to permit rubbing contact at very low speeds or rest.

Electromagnetic thrust bearing using passive and active magnets, for coupling a rotatable member to a stationary member

Abstract: An electromagnetic thrust bearing couples a rotatable member relative to a stationary member utilizing a combination of controllable electromagnets and a radially polarized permanent magnet, each physically associated with the stationary member. In one embodiment the rotatable member comprises a shaft having a pair of axially spaced apart thrust discs fixed thereto. A pair of solenoids are disposed about the rotatable member between the spaced apart thrust discs in oppositely facing relating to axially-facing sides of the thrust discs. The solenoids are capable of generating a controllable electromagnetic field. An arcuate radially polarized permanent magnet is disposed between the solenoids to generate a constant flux high density magnetic field between a solenoid housing and the thrust discs. In a second embodiment, a pair of solenoids are disposed about the rotatable member in facing relating on opposite sides of a single thrust disc. A radially polarized permanent magnet is disposed between the solenoids radially outwardly from the thrust disc for generating a constant flux high density magnetic field between solenoid housings and the thrust disc. A sensor determines the axial positioning of the rotatable member relative to the stationary member and provides input for controlling the positioning of the thrust disc(s) by varying the magnetic flux generated by the solenoids.

Air cycle machine with magnetic bearings

Abstract: An air cycle machine for producing a supply of cooled air and including a compressor rotor fixed to a shaft which is driven by a turbine rotor, the turbine serving to expand air which is pressurized by the compressor. Magnetic bearings support the shaft radially in a housing for rotation about a precisely established axis while a magnetic thrust bearing keeps the shaft in a precisely fixed axial position. The housing and the bearings are constructed as two split sections to permit the housing and the bearings to be separated radially and facilitate repair and/or replacement of the shaft and other internal components.

Application of a Mixed Lubrication Model for Hydrostatic Thrust Bearings of Hydraulic Equipment

Abstract: On mixed and fluid film lubrication the characteristics of hydrostatic bearings for hydraulic equipment are studied numerically. By applying a mixed lubrication model derived in a previous paper to the bearings, we clarify the effects of the surface roughness, eccentric or moment loads, supply pressure and speed of rotation on the friction, flow rate, and power losses. Introducing the concept of a ratio of hydrostatic balance, we show that the minimum power loss is given as the ratio becomes close to unity

Scroll type compressor

Abstract: PURPOSE:To prevent seizure trouble or the like due to an outflow of oil by forming a groove in a back surface of an end plate in a turning scroll and also interposing an oil seal material in this groove, thus by interrupting oil passages in the internal/external periphery of a thrust bearing for supporting a plane of the end plate. CONSTITUTION:In a scroll type compressor, both fixed and turning scrolls, formed with volute laps on surfaces of the respective end plates, are meshed by shifting a phase each other. A back surface in an end plate 21 of the turning scroll is supported by a thrust bearing 74. In the above constitution, an oil seal groove 77 is formed in the back surface in the end plate 21 of the turning scroll to interpose an oil seal material 75 in this groove 77. Oil passages with the internal/external periphery in at least one side of the thrust bearing 74 are interrupted. In this way, oil accumulated in a balance weight chamber 61 is prevented from flowing in a suction cavity 16. Accordingly, a seizure trouble or the like caused by insufficient lubricating oil can be prevented from being generated.

Fluid dampened support for rolling element bearings

Abstract: A fluid dampened support for a rolling element bearing such as a ball bearing, needle bearing, roller bearing and the like. The fluid dampened support includes a network of closely spaced beams which support the outer race of the roller bearing for movement in any direction. A liquid is provided in the spaces between the beams to dampen such movement. The structure and space between the beams is designed so as to provide virtually any reasonable damping characteristics. By providing such damping characteristics, the bearings are able to limit or damp out the vibrations occurring when the supported member passes through natural frequencies before reaching operating speed. This allows use of the rolling element bearing in high speed equipment such as compressors and turbines.

Magnetically driven centrifugal pump

Abstract: In a magnetically driven centrifugal pump so designed that a drive power of an electric motor is transmitted from a magnets-embedded drive rotor to a magnets-embedded follower rotor which is opposed to the drive rotor for the formation of a magnetic coupling and is associated with an impeller by a rotating shaft, the rotating shaft is supported with a radial bearing of ceramic material of non-rotation which is fitted into a supporting member fixed in a pump casing, wherein a cushioning member is mounted compressedly in an interspace between a front end of the thrust bearing and a circular edged projection of the supporting member which are opposed to one another.

Bearing thrust assembly for planet gears in planetary gear carrier assemblies

Abstract: A planet gear is rotatably supported in a planet carrier assembly on needle bearings. A first, gear thrust washer bearing member permits relative rotation between the planet gear and the carrier assembly while transmitting thrust forces between the planet gear to the carrier. The thrust forces generated by the needle bearings are transmitted to the first, gear thrust washer bearing member through a second, needle, thrust washer bearing member which is disposed in a recess within the face of the planet gear and freely rotatable relative to the planet gear.

Pad type hydrodynamic thrust bearings having a modular construction

Abstract: A hydrodynamic bearing which includes a carrier (10) and a plurality of bearing pads (23) circumferentially spaced about the carrier. The pads may have a modular construction whereby pad portions are secured to support portions (72). The pads may also be releasably secured to the carrier (10). Various bearing pad constructions are contemplated.

Axial-flow fan motor

Abstract: A sleeve-type plain bearing of an axial-flow fan motor, made of sintered oilless metal, for bearing a rotation of a rotor has plural protrusions on a thrust bearing surface in a direction vertical to an axial direction of the rotor, and thereby lubricant impregnated in the sintered oilless metal is always supplied in spaces formed by the thrust bearing surface, the protrusions and a thrust plate provided on the rotation shaft.

Rotary engine with variable compression ratio

Abstract: A rotary engine in which two rotors having interleaving radial vanes (3,4,8,9) revolve inside a cylindrical cavity and are connected to a planetary output gear system which causes them to alternately speed up and slow down. An axial shaft (5) attached to one rotor and passing through the other rotor contains a thrust bearing (10) to prevent the rotors from moving apart. The rotor vanes and disk-shaped end plates (1,6) which contain cooling means divide the cylindrical cavity into four chambers in which intake, compression, explosion and exhaustion occur. A passageway (39,39') containing an adjustable, pressure-sensitive valve (40) vents the compression chamber to the intake chamber to allow the compression ratio to be varied and to provide for a greater compression ratio than expansion ratio.

Magnetic bearing-type turbine compressor

Abstract: PURPOSE:To decrease excess electric energy and calorific value and also to improve reliability of thrust control by arranging an adjusting valve in a connecting pipe of the back surface of a compressor disc to an outlet of a diffuser on the outlet and then controlling this adjusting valve. CONSTITUTION:A turbine disc 8 for adiabatic expansion high pressure gas is attached on one end of a shaft 12, and a compressor disc 2 for adiabatically compressing gas by power of the turbine disc 8 is attached on the other end. And the shaft 12 is supported by a journal bearing 13 and a thrust bearing to be controlled by electric current of electromagnets 14A, 14B. In this case, thrust force to act on the thrust bearing is always made to act on the turbine side. Moreover, an adjusting valve 19 is arranged in a connecting pipe 11 for connecting the back surface of the compressor disc 2 to the outlet of a diffuser 3 provided on this outlet. Moreover the current values of the electromagnets 14A, 14B for controlling the thrust part are detected, and a control unit 18 is operated by the adjusting valve 19.

Linear bearing compensation system

Abstract: An alignment compensation system for use with parallel linear bearings which isolates the linear motion system load or carriage plate from alignment errors in the system. Spherical bearings are mounted in bearing blocks, each spherical bearing having a support shaft therethrough to support a plate connected to a carriage or load plate. One of the bearings shafts is free to laterally float within its bearing block, thus providing for compensation of lateral misalignment of the linear bearing track. The other spherical bearing is held fixed within its bearing block. The linear system load or carriage plate is mounted on the spherical bearing shafts, thus isolating the carriage plate from alignment errors in the linear motion system.

Thrust bearing assembly

Abstract: The thrust bearing fits on a rotatable shaft having an annular groove or in a rotatable housing with an annular groove. One of the thrust bearing races has an axially extending flange with deflective tabs projecting from the flange. The deflective tabs deflect radially when the race is pushed over the end of the rotatable shaft or into a rotatable housing. The deflected tabs spring back into the annular groove when the thrust bearing is fully seated.

Thrust bearing assembly

Abstract: A fractional horsepower motor has a thrust bearing assembly (10) mounted on the motor shaft (62) to dampen the axial movement of the shaft (62). The assembly (10) includes a thrust collar (12) formed of resinous material and a thrust plate (14) formed of metal with a wave spring (16) positioned therebetween. Apertures (52) in the thrust plate (14) receive resilient hook projections (18) formed on the thrust collar (12) as a means for coupling the plate (14) to the collar (12). Torque transmitting projections (20) formed on the thrust collar (12) engage notches (36) formed in the thrust plate (14). The hook projections (18) and the torque transmitting projections (20) act together to capture and hold the wave spring (16) between the collar (12) and plate (14).

Magnetic bearing and mechanical thrust bearing device for positioning a body rotating relative to a stator body

Abstract: Device for positioning a rotating body movable about an axis in relation to a stator body including a magnetic bearing and a locking/releasing device. The locking/releasing device embodies a plurality of clamps with pads adapted to radially grip a shaft of the rotating body. The clamps are articulated on the stator body about axial pins spaced from the rotational axis and evenly distributed in an angular manner about the rotational axis, and can be pivotally moved about the axis, by a moving control part between a released configuration in which the gripping pads are at a maximum distance from the axis and a locked configuration in which the pads are at a minimum distance from the axis suitable for inducing radial clamping of the shaft.

Orbiting member fluid displacement apparatus with rotation preventing mechanism

Abstract: The present invention discloses a reliable rotation preventing/thrust bearing device for use in an orbiting member fluid displacement apparatus. The rotation preventing/thrust bearing device includes a discrete fixed portion, a discrete orbital portion, and bearing elements. The fixed portion includes a first annular race and a first ring, both of which are formed separately. The first annular race is placed in a loose fit surrounding a first annular step in an inner surface of the housing and the first ring is attached to the housing. The orbital portion includes a second annular race and a second ring, both of which are formed separately. The second annular race is placed in a loose fit surrounding a second annular step in an end plate of the orbiting member and the second ring is attached to the end plate of the orbiting member. A plurality of pockets of the rings face one another in generally aligned pairs. A bearing element is received in each aligned pair of pockets to prevent the rotation of the orbiting member by the bearing elements interacting with the first and second rings and to carry the axial thrust load from the orbiting member. The first and second annular anti-weal plates are overlaid surrounding the first and second annular races, respectively. The first and second annular anti-wear plates are fixedly placed within the first and second annular steps respectively in order to prevent the circumferential and radial movement thereof.

Actuating drive, in particular for heating valves, ventilation valves or air-conditioning valves in motor vehicles

Abstract: An actuating drive, in particular for heating valves, ventilation valves or air-conditioning valves in motor vehicles, consisting of a drive housing, an electric motor having an integrated thrust bearing (pivot bearing), a step-down drive and an output drive shaft. In conventional actuating drives, O-ring seals are used to decouple body noise, but these are installed in a fixed position so that both the rotor as well as the stator are forced to adopt the predetermined position with respect to one another. If the motor tolerances interact unfavourably, it is possible for a bearing and a thrust washer to touch in this case, as a result of which the efficiency is reduced. The present invention is intended to overcome these disadvantages. This is done by the position of the stator not being influenced by receptacles in the drive housing and by at least one elastomer buffer being used which decouples the motor from body noise axially as well, this elastomer buffer being designed such that it can compensate for motor inaccuracies with the aid of a flexible region.

Spindle motor using dynamic pressure bearings

Abstract: A spindle motor with an H-type pneumatic dynamic bearing has a high durability against repeated starts and stops of rotation. The H-type bearing is composed of a radial bearing member, thrust plates firmly fixed to opposite ends of the radial bearing member and a cylindrical radial sleeve, which form a radial pneumatic dynamic bearing and thrust pneumatic dynamic bearings. A stator core is fixedly secured around a rotary member, which is in turn fixedly secured around the cylindrical radial sleeve. A total thrust clearance a+a' of the thrust bearings is represented by an inequality of (a+a')/A< 2.5/104 based on a sliding surface diameter A of each thrust plate, a and total radial clearance b+b' of the radial bearing is represented by an inequality of (b+b')/B<5/104 based on a sliding surface diameter B of the radial bearing member.

Radial bearing assembly for a high intertia flywheel of a canned motor pump

Abstract: A canned pump is described which includes a motor, an impeller, a rotatable shaft, and a high inertia flywheel mounted on the shaft and within a hermetically sealed housing. The flywheel comprises a heavy metal disk made preferably of a uranium alloy and having an inner circumferential annular recess portion. One embodiment employs a radial bearing assembly mounted to a bearing housing member, which also carries a thrust bearing assembly, for bearing surface contact with the inner circumferential surface of a stepped portion of the flywheel assembly. A second embodiment employs a radial bearing assembly mounted on the bearing housing member for bearing surface contact with a journal on the outer surface of the shaft. These arrangements locate the radial bearing assembly within the vicinity of the inner circumferential annular recess portion of the flywheel.

Motor, a printer having such a motor and a disk drive system having such a motor

Abstract: A motor has a rotor mounted on a stator to rotate about a rotation axis. The rotor is driven due to the interaction of a drive coil on the stator and a permanent magnet on the rotor. A magnetic thrust bearing, having permanent magnets on the stator and rotor, applies a radial thrust force. The radially outer surface of the permanent magnet on the rotor abuts a part of the rotor, so as to resist forces on the permanent magnet at high speed rotation or due to thermal deformation. The permanent magnets on the stator and the rotor may be axially offset by an offset of not more than 1/4 the axial length of the permanent magnets, or the axial length of the longer of the permanent magnets if they have different axial lengths. This generates an axial thrust at the thrust bearing, which counteracts the attractive force between the permanent magnet and the drive coil, and also the weight of the rotor.

Bearings having spaced pads and methods of making the same

Abstract: A hydrodynamic thrust, journal or combined radial and thrust bearing and methods of manufacturing the same. The bearing includes a bearing pad structure that may change shape and move in any direction (six degrees of freedom) to optimize formation of a converging wedge for hydrodynamic operation, equalization of load on the bearing pads in thrust bearings and to adjust for any shaft misalignment. The bearing pad may be formed so as to contact the shaft in the installed state and to deflect under fluid film pressure. The shape of the pads may be altered to achieve desired deformations under load. The pads are supported by a support structure which can include one or more beam-like members. The support structure preferably includes a primary support portion, a secondary support portion and a tertiary support portion.

Drum motor for vcr

Abstract: A drum motor for a VCR includes radial and thrust hydrodynamic bearings that are composed of a rotor-side bearing member formed by bringing a pair of first and second thrust plates into direct contact with both end surfaces of a radial bearing element and integrating them into one unit, and a stator-side bearing member in the form of a radial sleeve the inner peripheral surface and both end surfaces of which respectively cooperate with the outer peripheral surface of the radial bearing element and the mutually facing surfaces of the first and second thrust plates. A rotor magnet is secured to a rotating shaft. A motor casing is secured to the outer peripheral surface of the radial sleeve. A stator unit is secured to the motor casing. A dynamic pressure generating groove is provided on either each end surface of the radial sleeve or each of the mutually facing surfaces of the first and second thrust plates. The run-out of a rotor-side unit in both the thrust and radial directions is made extremely small and the change in the relative height of the rotor-side unit in the thrust direction due to a change of the position of the motor in which it is used is minimized.

High pressure gas fitting for repeated connection and disconnection

Abstract: A high pressure fluid fitting is provided for repeated connection and disconnection. The fitting includes a threaded nipple and a flanged nipple configured for abutting end-to-end mating with one another. A thrust bearing formed from a metal harder than the flanged nipple is positioned adjacent the flange and on the side thereof opposite the mating face of the flanged nipple. A coupling nut with an inwardly extending annular flange is disposed over the flanged nipple and is threadedly engageable with the threaded nipple. The flange of the coupling nut moves against the thrust bearing and urges the nipples into tight sealing engagement. The smoothness and hardness and chemical dissimilarity of the thrust bearing avoid galling and other friction related damage to the fitting, and hence lead to an extended life for the fitting.

Linear actuation roller bearing nut

Abstract: A device for convening rotational motion of a threaded shaft to linear motion in parallelism with the shaft and having a high load carrying capacity and operating efficiencies that are on the order of 98 percent (98%), with the device including a roller bearing nut for the shaft that is arranged to provide a linear motion unit (for the device) and a housing annular structure arranged to be fixed from rotation and including a plurality of circularly and concavely shaped thrust teeth of essentially "V" configuration 360 degrees (360°) thereabout, of which such thrust teeth are of identical size and configuration and are disposed in coaxial side-by-side relation normally of the desired direction of linear motion and at a formula defined pitch that also exceeds the pitch of the shaft threading; cooperating between the shaft threading and the thrust teeth are a set of thrust rollers seated about the linear motion unit in uniformly spaced relation, with each thrust roller having two (and only two) spaced pairs of similar flanges each riding on both the shaft threading and one of the thrust teeth of the housing, with the spacing of such flanges of each such thrust roller being similar and formula defined, and with each thrust roller pair riding on only certain of the opposing thrust teeth, though the rest of such teeth are similarly engaged by the flange pairs of the other thrust rollers involved.

Thrust bearing for high speed screw compressors

Abstract: A screw compressor assembly, comprising a housing, a pair of rotors rotatably journaled in said housing, a bearing system supporting the rotors including a radial cylindrical roller bearing and thrust bearing means rotatably supporting the journals in the housing including a first angular contact thrust ball bearing having a predetermined contact angle in the range of between about 30° and 35°, and a second back-up angular contact bearing having a contact angle less than said contact angle of said first thrust bearing and in the range of between about 15° and 20°, the difference between the contact angles of the thrust bearing and backup bearing being at least between about 10° and 20° whereby the internal force due to centrifugal force is small and therefore the induced axial force in the bearing system is minimized.