Showing papers on "Bearing (mechanical) published in 1988"

Turbine engine assembly with aft mounted outlet guide vanes

Abstract: A turbine assembly includes an annular fairing and strut subassembly which provides mechanical strength to the turbine assembly and support for the rotor aft bearing. A readily demountable annular outlet guide vane assembly is mounted to the aft of the fairing and strut assembly for deswirling the exhaust gasses which exit the turbine assembly. The aft mounting of the outlet guide vanes allows for an axially shorter and lighter turbine engine design which removes greater inlet swirl than prior designs, with equal or less pressure loss.

Image bearing member and driving mechanism therefor

Abstract: The improvement is in the driving mechanism and positioning mechanism between an image bearing member and a main assembly of an image forming apparatus using the image bearing member. The image bearing member has a shaft receiving portion adjacent the center thereof to receive a positioning shaft of the main assembly when the image bearing member is mounted in said main assembly. By the receiving engagement, the image bearing member is correctly positioned with respect to the main assembly. The image bearing member is also provided with a driving force receiving portion where the image bearing member is engaged with a driving member of the main assembly so that the image bearing member can be driven from the main assembly. In such an arrangement, the shaft receiving portion and the driving force receiving portion are radially overlapped, at least in part, with each other as seen from a rotational axis of the image bearing member.

Load enhancement effects due to polymer thickening in a short model journal bearing

Abstract: A model bearing is described which is 20.0 mm in diameter and 2.5 mm in length; a short bearing of diameter to length ratio eight. The clearance is large (500 μm) and the rotor may be run true or eccentric on its own shaft; in each case the mean load and frictional (tangential) force is measured as the centreline eccentricity is varied. Comparison is made between the lubricating performance of Newtonian and highly elastic liquids; the latter give load enhancement ratios of up to 300 and reductions in coefficient of friction by factors of the order 30. These effects are greatly in excess of those obtained when dealing with bearing of diameter to length ratio close to unity; possible reasons for this are discussed. A Newtonian oil and a polymer-thickened oil are tested in the same way, the latter oil is found to give load enhancement ratios of 1.4 (true rotor) and 3.5 (eccentric rotor) with corresponding reductions of coefficients of friction by factors of 1.5 (true rotor) and 3.0 (eccentric rotor). Such effects had not previously been observed when using oils in the internal cylinder geometry (journal bearing type) although somewhat similar effects have been found in the external cylinder and squeeze film geometries. The rheological properties of the polymer-thickened solutions are measured and the relevance of the results to friction and load bearing discussed.

Sector interpolation of non-uniform arrays for efficient high resolution bearing estimation

Abstract: Bearing estimation is a fundamental array processing task for which attractive algorithms exist when the array is linear and uniformly-sampled. Since circumstances often require the use of an irregular two-dimensional array, the problem of interpolating a synthetic linear, uniformly sampled array from the real array is considered. Accurate interpolation is achieved by interpolating several synthetic arrays, each of which represents the real array over a limited sector of bearing angles. The utility of the method is demonstrated through a design example and simulation using a circular array and an eigenvector-based bearing estimator for linear, uniformly-sampled arrays. >

Acoustic emission monitoring of rolling element bearings

Abstract: The authors describe experimental efforts aimed at establishing the detection threshold for acoustic emission (AE) and vibration monitoring for a typical defect located in a standard ball bearing. An AE point contact transducer (PCT) has been developed: it is a rugged and compact device that can be used for various machinery diagnostic applications. Stress wave emissions in the frequency range above 100 kHz can provide a clear indication of the defect and thus provide an earlier and more reliable indication of bearing degradation. The digital data acquisition and analysis system used with the AE PCT is described, and AE and vibration analysis results are presented. >

Improvements in Lightly Loaded Rotor/Bearing and Rotor/Seal Models

Abstract: Amelioration des modeles de calcul des systemes rotors-paliers ou rotors-joint d'etancheite faiblement charges

Superconducting rotating assembly

Abstract: A non-contacting superconducting rotating assembly is described which includes a floating, unsupported and stable rotor. The assembly includes first and second bearings comprised of a material which exhibits Type II superconducting properties. The rotor includes a magnetic pole at each of its extremities, each pole resting in a bearing. The polar axis of each pole is colinear with the rotating axis of the rotor. A temperature bath is provided for maintaining the bearings at or below their critical superconducting temperature and a motive mechanism provides for rotation of the rotor. Each magnet pole is thereby levitated and adapted to rotate in a stable, non contacting position by the field and pinning effects generated by the associated bearing.

Oil film bearing and bushing

Abstract: An oil film bearing for rotatably supporting the journal surface of a rolling mill roll neck on a hydrodynamically maintained oil film. The bearing includes a bushing adapted to interrupt the load carrying continuity of the oil film and to subdivide the load zone into compound pressure zones.

Split bearing assemblies, method for making

Abstract: Method for making split bearing assemblies by fracture separation, particularly pertaining to engine connecting rods, include steps wherein previously clamped body and cap portions are quickly forced apart longitudinally to cause fracture separation of both pairs of integral legs in a single motion while the cap and body are restrained from substantial relative rotation by a clamp of a fracture separation apparatus.

Modular joint prosthesis assembly and method of removing

Abstract: An improved modular prosthetic joint has a stem portion embedded in a bone with a removable bearing head frictionally mounted on the stem portion. The bearing head has a bore which mates with a tapered shaft of the stem portion. The bearing head has a generally thin wall defining its continuous and unbroken bearing outer surface, with a wall portion extending directly over the tapered shaft which is thinner than the remainder of the bearing head wall. A puller engages an annular shoulder of the bearing head to pierce through the thinner wall portion of the bearing head, engage the tapered shaft and urge the bearing head away from the tapered shaft. Thus, the bearing head is pierced and removed from its associated stem portion, and second replacement bearing head is then mountable on the tapered shaft by impaction.

Side assembled clip for self-aligning bearing

Abstract: A clutch release bearing assembly (1) includes a tubular plastic carrier member (3) for actuating a self-aligning clutch release bearing (15, 33, 35). The bearing (15, 33, 35) is connected to the carrier (3) with a rigid annular clip (9). The rigid clip (9) is formed with recesses (19) or tabs (61) which receive or engage complementary mating portions (23, 62) provided on the carrier (3). A radial flange (11) is formed on the clip (9) for axially restraining the bearing (15, 33, 35) on the carrier (3). Bearing seals (39, 49) may be provided on the flange (11) to prevent debris from entering the bearing assembly (1).

End frame and stator assembly for a dynamoelectric machine

Abstract: An end frame and stator assembly for a dynamoelectric machine such as an alternating current generator. The assembly comprises a slotted stator core that supports a stator winding, a rotor bearing and a metallic heat dissipating insert that supports the bearing. The assembly has a plastic housing that is comprised of plastic material that is molded to the stator core and insert. The plastic housing does not encapsulate the stator winding. The metallic insert conducts heat away from the bearing and also adds stability to the plastic housing.

Magnetic speed sensor with an adaptive threshold circuit for use with a bearing assembly

Abstract: A magnetic sensor bearing utilizes an adaptive threshold circuit for signal processing in order to compensate for external factors such as temperature, stress, aging, and external magnetic fields which all affect a fixed reference signal used with a comparator. As the magnetic sensor's output signal drifts due to these external factors, the adaptive threshold circuit causes the reference signals to drift in a complementary manner so that the magnetic sensor bearing continues to function properly in spite of the external factors.

Printing cylinder sleeve application apparatus and method

Abstract: To prevent shifting of an eccentric (12, 33) about a bearing (8, 26), which it surrounds to provide for adjustable positioning of a printing cylinder (3) in a printing machine, upon release of the eccentric from a sidewall (1) of a printing machine to permit placing a sleeve (15) over the cylinder, the eccentric, in accordance with the invention, is locked in position to the shaft of the cylinder, or to the sidewall, or a releasable jaw of the machine prior to release of the eccentric from clamp holding position between holding jaws (13, 27, 28) which, in operation, retain the eccentric in position on the machine.

Hydraulically damping elastic bearing

Abstract: Hydraulically damping elastic bearing, in particular engine mounts for motor vehicles, with two rigid end walls opposite one another in the axial direction and at least two chambers containing damping fluid arranged axially one behind the other, whereby the chambers are connected for fluid communications with one another by a passage running in an annular fashion. For the variable modification of the length of the passage, partitions are inserted in the component containing the passage, which partitions divide the passage into individual passage segments connected for fluid communication with one another by an opening.

Frictional Instabilities in Ball Bearings

Abstract: Computer modeling techniques are used to investigate instabilities in the motions of ball and cage in a ball bearing. As the friction at ball/race and ball/cage contacts increases, the cage mass center whirl orbit changes from circular to polygonal and then to a rather erratic shape under excessive friction. The corresponding variations in whirl velocities also increase to represent bearing squeal. It is shown that cage instabilities are directly dependent on the ball/race traction slope, under low slip velocities, and the friction coefficient at the cage interfaces. Under steep traction slopes, the variation in traction at higher slip rates is also significant in high-speed bearings. In particular, it is found that a negative traction slope, in the high-slip region, may produce appreciable ball skid which promotes excessive interaction in the cage pockets and, perhaps, the most damaging instability of the cage, where the mechanical interactions progressively increase to indicate significant potentials fo...

Compact ferrofluidic electrically conducting sealed bearing

Abstract: A sealed, rolling element bearing includes an inner race attached to a shaft, an outer race attached to a housing, a plurality of rolling elements in an annular region and a pair of shields extending inwardly from the outer race toward the inner race so as to substantially enclose the annular region. The shields have a closely-spaced, noncontacting relationship with the inner race thereby defining gaps. The elements of the bearing are of magnetically permeable material, and the sealed bearing includes means for producing a magnetic field in the gaps and in the regions where the rolling elements contact the races. A ferrofluid is retained by the magnetic field in the gaps for sealing and in the regions of contact between the rolling elements and the races for lubrication. A reservoir of ferrofluid in the regions between the two seals replenishes ferrofluid lost at the sealing and lubrication areas. The magnetic field can be produced by permanent magnetization of the bearing assembly or by axially polarized permanent magnets located on either or both ends of the outer race. Such a bearing may be used with a magnetic or nonmagnetic shaft and permits relative motion between the shaft and the housing. The housing material is of nonmagnetic type when external magnets are used.

Door mirror for vehicles

Abstract: The door mirror according to the present invention is a so-called tiltable door mirror for vehicles. The bearing member to bear the shaft of the mirror base which is to be fixed to the vehicle door is formed integrally with the synthetic resin-made mirror housing. The bearing member is formed as a bearing cylinder inside the mirror housing. Being in contact with the bearing surface of the bearing cylinder, the shaft pivotably supports the mirror housing. There is provided between the inner wall of the bearing cylinder and the shaft a U-shaped leaf spring which is in contact at the one end thereof with the inner wall of the bearing cylinder and at the other end with the flat surface formed at a part of the shaft, whereby the friction generated under the action of the leaf spring helps to block the mirror housing from pivoting and thus the mirror housing can be held in the normal position. The shaft has disposed at the end thereof a stopper to prevent the mirror housing from moving axially of the shaft. When a big external force is applied to the mirror housing, the portion of contact between the leaf spring and the shaft moves from the flat surface to the circumferential surface against the force of the leaf spring, so that the mirror housing is pivoted slowly from the normal position to a front or rear position with respect to the normal position. The door mirror of the present invention consists of a reduced number of elements and has a simplified structure. Furthermore, since it can be installed very easily, the manufacturing costs can be reduced very much.

Clutch release bearing

Abstract: An improvement to clutch release bearings which comprise an operating element and a drive element retained together and controlled by axially-acting elastic members formed by a limited number of separate elastic clamps. The elastic clamps are operable to apply a radial flange of the drive element against a radial flange of the operating element. Each elastic clamp comprises an axial part and a radial part. The axial part extends across the flange of the operating element through an opening in the flange. Two axial channels are provided in association with this opening to hold this elastic clamp radially in place. The invention is particularly applicable to self-centering clutch release bearings for automobiles wherein the bearings are capable of permanent self-centering.

Clutch release bearing device

Abstract: A clutch release bearing device including a clutch release bearing abutted to a diaphragm spring of a clutch of a vehicle, and a holding arrangement for holding the bearing in a predetermined condition The holding arrangement includes a sleeve of synthetic resin, a metal anvil extended radially outwardly therefrom to receive an operation force applied by a fork member, and a bearing case for connecting the clutch release bearing to the bearing holding arrangement The sleeve, the anvil and the bearing case are coupled to each other by punching a portion of the bearing case axially to engage with the periphery of a through hole formed in the anvil and then molding the sleeve to the engaged portions of the anvil and bearing case

Bearing material and plastic bearing.

Abstract: A bearing material mainly comprising plastics and a plastic bearing made thereof. The bearing material is composed of 30 to 98 wt % of glassy carbon and 70 to 2 wt % of plastics, and has persistent, excellent abrasion resistance, sliding properties, and heat resistance.

Bearing of an axle drive bevel pinion

Abstract: A pinion shaft of an axle drive bevel pinion mating with a bevel gear is disposed in two tapered roller bearings, the joint outer race of which is flanged onto the axle housing. In order to lubricate the tapered roller bearings with splash oil and avoid dirt deposits in the bearing area, the outer race of the tapered roller bearings has an oil feeding duct to a collecting pipe arranged above, and at its underside, an oil return duct to the transmission oil sump.

Bi-compliant rotor stepper motor for an actuator in a disc drive

Abstract: The disclosure relates to a technique for effectively floating the rotor (37) of a disc drive motor, thereby permitting small motions in the axial (non-critical) direction while maintaining significant stiffness of the radial (critical) direction. This is achieved by providing an electromagnetic actuator inluding a stepper motor having a housing, a stator located within the housing, and a rotor (37) positionable relative to the stator driving a motor shaft to wind and unwind a band (14) and thereby position the carriage. The drive shaft (12) passes through ball bearings (30) which support the shaft for rotation. The ball bearings themselves fit within an annular end bell portion (39) of the motor housing which defines a channel for the bearing. An injected elastomer (33) forms a tight-fitting ring between the bearings and the internal wall of the end bell (39), thereby radially supporting the outer race of the bearing. Preload springs (36) are then installed on both sides of the rotor between the internal end walls of the end bells and both outer races of the bearing. the installation of these springs effectively floats the rotor to allow some distortion of movement of the rotor in the axial direction, while minimizing or eliminating the radial deflection components.

Segmented sliding bearing arrangement for portable lathe

Abstract: A portable lathe tool includes fixed and rotating split rings (12, 22) the fixed ring (12) arranged to be secured to a pipe workpiece (18), the rotating ring (22) being relatively rotatable with respect thereto for carrying a tool (34) capable of performing a machining operation on the workpiece as it is driven around the circumference of the latter. A bearing arrangement for supporting the relatively rotating ring on the fixed ring is disclosed as having a plurality of discrete, circumferentially spaced bearing segments (48), each having converging radial and thrust bearing surfaces (52) for engaging the rear end area of the rotating ring for axially, radially and rotationally locating and guiding the rotating ring relative to the fixed ring. An adjustment system (53) is provided for accurately locating and adjusting the position of each of the bearing segments relative to the fixed ring to permit compensation for wear and dimensional variations.

Earth boring bit with convergent cutter bearing

Abstract: An earth boring bit having a body and a cantilevered bearing shaft extending inwardly and downwardly from the body. A rotatable cutter with an open end is assembled over the shaft, which has a journal surface formed around a longitudinal axis. The cutter has a bearing surface sized to permit assembly over the journal surface of the shaft. At the open end of the cutter bearing surface is a seal recess which includes an intersecting wall that defines an annular, generally curved corner to oppose the journal surface of the shaft. The cutter bearing surface has a curved outer region that converges from the annular corner of the seal recess into an inner region to reduce the stress the corner induces upon the journal bearing surface of the shaft, including the stress induced by cutter cocking during drilling.