Showing papers on "Bearing (mechanical) published in 1978"

Rotary-anode X-ray tube

Abstract: A rotary-anode X-ray tube, comprising a rotary anode which is journalled in a vacuum-tight housing by means of at least one sleeve bearing whose mutually co-operating bearing surfaces are made of W or Mo or of an alloy of W and Mo. The bearing is lubricated by Ga or a Ga alloy having a melting point below 25° C. The Ga or Ga alloy lubricant is in molecular wetting contact with the bearing surfaces so that the bearing surfaces are completely separated from each other in the loaded condition. During standstill, as well as during rotation, the lubricant is not forced out of the bearing, so that the bearing surfaces cannot become fused. The wear and the bearing noise are therefore extremely low. The desired, thorough wetting is obtained by making the bearing surfaces, as well as the Ga alloy, oxide-free before they are brought into contact with each other.

Hydrodynamic air lubricated compliant surface bearing for an automotive gas turbine engine. 1: Journal bearing performance

Abstract: A 38.1 mm (1.5 inch) diameter Hydresil Compliant Surface Air Lubricated Journal Bearing was designed and tested to obtain bearing performance characteristics at both room temperature and 315 C (600 F). Testing was performed at various speeds up to 60,000 rpm with varying loads. Rotating sensors provided an opportunity to examine the film characteristics of the compliant surface bearing. In addition to providing minimum film thickness values and profiles, many other insights into bearing operation were gained such as the influence of bearing fabrication accuracy and the influence of smooth foil deflection between the bumps.

Wind powered electrical generator

Abstract: A wind powered electrical generator having a rotatable wind wheel (21) carrying one of the armature (42) or field structures and a plurality of windvanes (45) connecting the rim to a central shaft (28), a stator (39) carrying the other of the armature or field structures, and a supporting structure (22) for the windwheel rotor shaft and the stator. The armature winding is carried by the windwheel at its perimeter, and the field structure is a ring structure which lies just radially outward of the armature winding and is carried by the fixed housing structure which perimetrally surrounds the windwheel. Bearing support (48) provided at the perimeter of the windwheel by low friction bearings carried by the fixed housing structure minimizes bearing stresses developed at the supporting shaft under wind loading conditions. The electical output of the generator is compared against a reference standard to generate corrective error signals when the phase of the generated electrical signal differs from that of the reference standard. Corrective mechanisms utilized are means for changing the angle presented by the windwheel blades to the wind; a braking structure; and a feedback field winding.

Apparatus for measuring bearing forces

Abstract: An apparatus for the measuring of external forces by means of a preloaded roller bearing, provided with at least two strain gauges which serve to measure the forces applied to the bearings, in which apparatus the resistance variations of the strain gauge(s) are recorded individually, amplified individually and rectified individually, whereby signals which are proportional to the external forces are obtained through subtraction from the rectified signals, while due to said subtraction those parts of the individually amplified and rectified signals due to internal forces are eliminated.

Optimum Bearing and Support Damping for Unbalance Response and Stability of Rotating Machinery

Abstract: This paper presents a rapid approximate method for calculating the optimum bearing or support damping for multimass flexible rotors to minimize unbalance response and to maximize stability in the vicinity of the rotor first critical speed. A multimass rotor is represented by an equivalent single-mass model for purposes of the analysis. The optimum bearing damping is expressed as a function of the bearing stiffness and rotor modal stiffness at the rigid bearing critical speed. Stability limits for aerodynamic cross coupling and viscous internal rotor friction damping are also presented. Comparison of the optimum damping obtained by this approximate method with that obtained by full scale linearized transfer matrix methods for several rotor-bearing configurations shows good agreement. The method has the advantage of being quickly and easily applied and can reduce analysis time by eliminating a time consuming search for the approximate optimum damping using more exact methods.

Filtration effects on ball bearing life and condition in a contaminated lubricant

Abstract: Ball bearings were fatigue tested with a noncontaminated lubricant and with a contaminated lubricant under four levels of filtration. The test filters had absolute particle removal ratings of 3, 30, 49, and 105 microns. Aircraft turbine engine contaminants were injected into the filter's supply line at a constant rate of 125 milligrams per bearing hour. Bearing life and running track condition generally improved with finer filtration. The experimental lives of 3 and 30 micron filter bearings were statistically equivalent, approaching those obtained with the noncontaminated lubricant bearings. Compared to these bearings, the lives of the 49 micron bearings were statistically lower. The 105 micron bearings experienced gross wear. The degree of surface distress, weight loss, and probable failure mode were dependent on filtration level, with finer filtration being clearly beneficial.

Lubricating device for power transmission unit

Abstract: In a power transmission unit, a protrusion is provided on an inner wall of the transmission housing to be splashed with lubricating oil pumped up by rotation of an idler gear on the idler shaft, and an oil receiver is arranged under the protrusion to receive the lubricating oil dropping from the protrusion thereby to convey the oil into the bearing at one side of the idler shaft.

Bearing assembly with thermal adaptor

Abstract: A machine tool spindle bearing assembly employing front and rear bearings each having radially compressed rolling elements between an inner race press fitted on the spindle and an outer race press fitted into a section of a thermal adaptor mounted on the spindle housing through a heat barrier section. The combined masses of each outer race and the section of the thermal adaptor supporting the outer race are related to the total mass of the rolling elements of the bearing so that, in response to the heat generated by the rolling contact forces between the rolling elements and the outer race, the mean diameter of the track of the outer race increases to twice the increase in diameter of a rolling element. The thermal barriers of the thermal adaptors are radially rigid; the thermal barrier of the front thermal adaptor is axially rigid and the thermal barrier of the rear thermal adaptor is axially flexible.

Equipment for the detection of rotation parameters in particular for a wheel-velocity sensor

Abstract: A wheel velocity sensor of the type having a toothed rotor and a stator with a detecting head mounted adjacent the rotor in proximity with the rotor teeth. The rotor is assembled with the bearing seal in the wheel hub as an integrated unit, being encased within a cavity formed in the seal to receive the rotor. The detecting head of the stator contacts the face of the seal, which is coated with a low friction material, so that a constant gap is maintained between the detecting head and rotor during rotation of the wheel to obtain more accurate wheel velocity signals.

Soft inplane helicopter rotor

Abstract: A helicopter rotor hub assembly (10) in which a blade grip (30) extends inboard of a yoke (14) and transfers centrifugal forces to the yoke (14) through a spherical elastomeric bearing (38). Pitch change of the grip (30) and blade (32) is accommodated by the spherical elastomeric bearing (38) which also acts as the pivot point for lead-lag motion of the blade (32) and grip (30). A lead-lag damper (22) is located inboard of the elastomeric bearing (38) and is connected between one end of the grip (30) spaced away from the lead-lag pivot and the yoke (14) for damping the lead-lag motion between the grip (30) and yoke (14).

Retainer for bearing lock nut

Abstract: A retainer for preventing relative rotation of a lock nut threaded on a shaft to preload an adjacent bearing assembly includes a serrated bore for engaging a splined shaft portion extending through a bore and axially-extending projections for engaging notches or the like formed in the lock nut. A device, such as a sprocket wheel, mounted outward of the retainer maintains the retainer in axial engagement with the lock nut. The retainer can be deformed during assembly to facilitate proper alignment of the lock nut on the shaft. The retainer is advantageously employed to maintain preloads on tapered roller bearings utilized to support the final drive shafts in heavy earthmoving equipment.

Bearing support structure combining fluid damping and spring damping apparatus

Abstract: A bearing support structure capable of reliable operation in a rotary machine is disclosed. Various construction details which enable the damping of vibratory energy are discussed. Fluid damping and spring damping apparatus are combined in forming an effective structure for damping synchronous and non-synchronous vibratory energy. The system is built around a plurality of arcuate beams which effect spring damping, and which collaterally form chambers for the containment of a fluid damping medium.

Axial bearing for a roller drill bit

Abstract: An axial thrust bearing for a roller drill bit comprising a pair of one piece diamonds mounted in the axial end face of the journal and the interior of the cutting roller supported for rotation on the journal. Each diamond is mounted on a cup-shaped casing made of a softer metal than the journal and cutting roller. Preferably the confronting engaging bearing surfaces of the diamonds are spherical.

Bearing with bearing cage

Abstract: An annular cage for the rollers of a bearing is located in the annular space between two bearing races and is normally spaced from both races when concentric. The cage is so constructed that, when unbalanced forces on the cage during rotation in the bearing tend to move the cage from its concentric position into contact with a piloting surface, hydrodynamic forces are developed which act to keep the cage out of contact with that surface.

Compliant hydrodynamic bearing with improved support element

Abstract: A compliant, hydrodynamic fluid film bearing for supporting a rotating rotor on a stationary mount, includes a bearing sheet supported by a compliant resilient support member formed of two sheets, each having raised resilient elevations in the form of corrugations. One of these sheets is inverted with respect to the other and the corrugations on the two sheets are vertically aligned and face in opposite directions, each corrugation forming one-half of an elongated tubular spring. A metal sheet lies between the two support sheets and all three sheets, and the bearing sheet, are fastened at one end to a pair of spacer blocks. The yield strength of the support member is thus raised above the yield strength of a single support sheet while maintaining low stiffness.

Modular compliant hydrodynamic bearing with overlapping bearing sheet

Abstract: A resilient, compliant, hydrodynamic fluid film bearing, for positioning between a stationary member and the bearing surface of a rotor, includes a bearing module formed as a unitary one-piece article having a resilient support section and a bearing surface section which overlaps its own resilient support section, or that of the next adjacent module, to provide a low cost bearing which is easy, fast and economical to manufacture and assemble.

Support element for compliant hydrodynamic journal bearings

Abstract: A compliant hydrodynamic fluid journal bearing system tolerant of strong misalignment forces includes an end section at each axial end of the bearing system which lies parallel to the direction of rotation of the rotor. The end sections are more compliant than the central section of the bearing system and can deflect independently of it to conform independently with a misaligned rotor bearing surface without distorting other portions of the bearing. The surface area of the bearing which is thus made available to bear loads is maximized, thereby increasing load capacity and misalignment tolerance of the bearings.

Insulation molded, load bearing, prefabricated panels

Abstract: A prefabricated building panel capable of bearing weight supporting loads, comprised of a pair of spaced apart rectangular metal frame members which are joined along one side by fastening bolts holding them in rigid relationship with respect to each other, and which have on their opposite side a locking means for locking one pair of panel frame members to the fastening bolts of another pair of frame members, and having the interior panel space defined by the frame members filled with an expandable polymeric insulative material which is molded directly to the panel frame members. As a result, load bearing steel stud frame members can be provided with insulation already installed at the factory, thereby eliminating separate insulating steps at the job site.

Sensor for generating nuclear magnetic resonance signals

Abstract: A sensor for generating nuclear magnetic resonance signals comprises a radio-frequency NMR coil wound around a frame accommodating a rotor with a test sample. The rotor is rotatably mounted in a gas bearing which is formed by the surface of revolution of the rotor, the internal surface of the frame and a gap between the above-mentioned surfaces. The compressed gas is delivered to the gap so as to produce the gas pillow of the gas bearing and to provide thermostatic control of the test sample. The rotor is provided with a rotation means.

Clutch release bearings

Abstract: There is disclosed a clutch release bearing comprising a plastic operating member having an axial sleeve and a transverse flange, and a drive or thrust member comprising a ball bearing. One of the races, here the outer, is adapted to bear against a washer bearing member through an annular holding member disposed on one side of the transverse flange. Passageways are formed in the flange to provide access for an associated actuating member to the bearing member from the other side of the flange. The holding member for the bearing member preferably comprises a washer portion, a slotted annular rim divided into segments with radially outwardly extending annular lip on the free end of the rim bearing against a transverse shoulder formed on a radially inwardly extending bead at the free end of an axial rim on the operating member. Alternatively, the annular holding member may consist of a washer, or an axially extending rim.

Bearing and motor temperature monitor

Abstract: A system for monitoring the temperature of a plurality of bearings and motors, for example in a grain elevator, includes a plurality of sensors associated with the respective bearings and motors whose temperatures are to be monitored. A first circuit energizes a display for providing a readout of the temperature at each sensor location, and a second circuit compares the temperature at each sensor with a maximum desired temperature for its associated bearing or motor, and energizes an alarm when this desired maximum is exceeded. A third circuit drives a display indentifying the sensor being monitored by the first and second circuits. A malfunction detector circuit produces an observable indication in response to an open circuit condition at any of the sensors. The sensors each comprise a temperature sensitive diode and a matching resistor encased in a housing by a highly thermally conductive material, the housing being suitably formed to be mounted in a close thermal relationship with the motor or bearing to be monitored.

Method for the advance indication of damage to wheel bearings

Abstract: In a method for advance indication of the possibility of damage occurring to wheel bearings of vehicles, particularly railroad vehicles, the temperatures of the wheel bearing sets of a plurality of wheels are monitored by temperature detectors fixedly mounted on the vehicle A determined value is derived from the measured values of temperature, and this determined value is compared with the temperature of a further temperature detector, in order to produce a warning signal The warning system is incorporated in the vehicle itself, and provides a warning to the vehicle personnel

Apparatus for lubrication of a differential bearing mounted between concentric shafts

Abstract: An apparatus is provided to supply oil to a differential bearing mounted between relatively rotating concentric shafts, for example, inside a gas turbine engine. In one form, the apparatus includes a fixed nozzle that injects oil into an annular collector dam mounted on the outer floating shaft. The dam construction utilizes centrifugal force to cause the oil to flow forward through passages into an interior area of the outer shaft. Inside such shaft, the oil is directed by dispensers into an oil transfer tube that traverses the distance inside the shaft from the dispensers to the bearing. The inside wall of the tube is flared to a larger diameter at the forward end, and the centrifugal force resulting from shaft rotation forces the oil forward into the bearing. At the forward end, the transfer tube contacts the outer race of the bearing thereby lubricating the bearing throughout a 360 degree surface area. After lubricating and traversing the rotating contact surfaces of the bearing, the oil is directed to a scavenge cavity for recycling through the engine lubrication system.

Self-propelled vehicle

Abstract: Self-propelled vehicle with articulated arms able to move in a tube or in a laminar space defined between two approximately parallel surfaces. It comprises a body equipped with at least one driving and guide wheel which bears on a surface on which the vehicle moves and at least two pivoting arms articulated on the body and terminated by bearing members which slide or roll on a surface facing and opposite to the first surface. It also comprises a device which transmits a pivoting torque to the arms in such a way that said arms bear on said opposite surface and by reaction apply the driving wheel against the first surface. A particular application is to the inspection of pipes within a nuclear installation in a radioactive atmosphere.

Bearing arrangement for shaft of rotary compressor

Abstract: A slide bearing journals the rotor shaft in the compressor housing with a clearance radially of the shaft; and an anti-friction bearing mounted on the shaft journals it axially thereof, the housing having a fixed support surface against which the anti-friction bearing abuts axially in one direction and which allows radial movement thereof. Yielding means are provided to press the anti-friction bearing against the support surface with a predetermined precise force.

Endoprosthesis for a knee joint

Abstract: A knee joint endoprosthesis includes a femoral component, a tibial component and a slide bearing providing for relative pivotal movement between the components and formed of a femoral bearing half carried by the femoral component and a tibial bearing half carried by the tibial component. The bearing halves are arranged for being pressed to one another while free from being connected to one another. There is further provided an arrangement for cardanically guiding the bearing halves with respect to one another with degrees of freedom in horizontal and vertical directions.

Vertical axis hermetic rotary helical screw compressor with improved rotary bearings and oil management

Abstract: In a vertical hermetic compressor, an inner cylindrical housing coaxially mounted within a sealed outer enclosure, sealably carries at its lower end, paired helical screw rotors defining with the inner housing a screw compressor compression chamber and supports coaxially with one of the screw rotors and constituting an axial extension thereof the compressor electrical drive motor by longitudinally spaced tapered roller bearings. Oil is bled from the sump and fed to the suction inlet tube to the compressor upstream of the working gas filter. Compressed working fluid is discharged axially downwardly with the lower tapered roller bearing assembly providing a minimal high pressure gap between the screw rotor ends and the stationary end plates. Entrained oil from the discharge passage which extends through the electric motor rotor seeks the suction side of the compressor through the upper of the two tapered roller bearing pack assemblies for controlled continuous lubrication of the upper bearing assembly. The compressed working fluid discharges axially through the center of the sealed outer enclosure at its upper end free of oil which is separated by impact with a curved plate deflector overlying the upper end of the electric motor and by centrifugal force provided by the electric motor rotor rotation. The upper bearing pack assembly for the screw rotors may employ needle bearings instead of tapered roller bearings and the lower bearing pack assemblies may incorporate radially extending needle bearings for thrust take up in lieu of one set of tapered roller bearings, with the needle bearings carried by a spherical, self-aligning mounting assembly. A capillary line passing through the compressor inlet passage carries oil from the sump to an injection port opening to a closed thread just after suction cut off for lubricating and sealing of the screw rotors.

Method and apparatus for making an encapsulated plug-in blade fuse

Abstract: A method and apparatus for making an encapsulated, three-piece electrically conducting component, such as a fuse, are provided wherein a progressive stamping die is used to form a pair of spaced apart blades in a sheet stock of electrically conducting metal. Each blade has at one end a terminal portion connected to a carrier member formed from the strip and at the other end a pair of spaced-apart rear bearing members and a flexibly hinged front bearing tongue disposed between the rear bearing members. The rear bearing members have a cradle with a substantially concave cross section for receiving a conducting wire therein. In the die, the tongue is forced outwardly away from the rear bearing members to provide an opening between the distal end of the bearing tongue and the cradles of the rear bearing members. A continuous wire may be inserted into the blades. Then the force on the tongue is relieved to permit it to move back toward the rear bearing members to securely clamp the wire in the cradles. The wire is severed on each side of a pair of blades to form a three-piece structure with a wire segment extending across, and being clamped between, a pair of spaced-apart blades. A plurality of such three-piece conducting components, still connected to the carrier member, may be then placed in a suitable molding apparatus wherein each wire segment and portions of the pair of blades of each component is encapsulated with a unitary body of electrically insulating thermoplastic material.