Abstract: An inbalance detecting and correcting station for a disk-shaped rotor. The system rotates a rotor up to speed at a measuring station, and detects reflections from the rotor. A peak among the reflections is detected in steady state, and 80% of this peak is taken as a trigger level. The peak is then used to provide a phase reference whenever the reflection exceeds the trigger level. Inbalance data is determined based on the phase 0 detected at this peak. An inbalance correction station corrects for this inbalance, using the same trigger level detected in the inbalance measuring station. This trigger level is coupled from the inbalance detecting station to the inbalance correction station, and a photosensor detects reflections from the same rotor. These reflections from the same rotor are used with the same trigger level to produce pulses at appropriate times without having to re-measure the trigger level.

Abstract: The present invention provides for a method of generating an electronic bobweight signal used to offset an unbalanced signal before the unbalance signal is received at the input portion of the electronic circuitry of the unbalance detection system. The electronic bobweight signal and unbalance signal are matched in their phase angle and are each sampled a specified number of equally spaced times per revolution of the workpiece to provide accurate bobweighted unbalance data without the need for use of physical bobweights and their inherent disadvantages.

Abstract: An unbalance measuring procedure and circuitry therefor employs correction weights for the compensation of unbalance of a rotating component under test. After a measuring run, stored and displayed unbalance information is compensated by a compensating weight at the angular position displayed and a control run is carried out, the results of which are also stored and displayed. The balancing is interrupted and ended if a low level threshold value is not reached. For purposes of automatic adaptation of a balancing unit, the measurement run is simultaneously used as a control and calibration run to check the balancing quality obtained by the initial placement of a compensating weight.

Abstract: The position and magnitude of an unbalance correction in specified correction planes is determined for the purpose of reducing a determined unbalance in a body. Such correction planes may comprise the inner and outer surfaces of a wheel. Incremental correction is provided with respect to magnitude and continuous correction is provided with respect to the position in order to achieve minimalization of the residual static unbalance with only one correction weight per correction plane. The existing unbalance in the correction planes according to magnitude and position is determined, and the influence of various corrections upon the static and the dynamic residual unbalance that can be accomplished with one correction weight per correction plane are also determined. Corrections are provided in the correction planes for balancing that produce the minimally possible static residual unbalance and which fall within predetermined limits in each correction plane.

Abstract: The balancing machine of the present invention automatically determines the position of unbalance in a rotating part and stops the rotating part with the unbalance position in a predetermined location. Sensors on the bearings holding the rotating part generate signals proportional to the instantaneous unbalance. These signals are filtered and digitized at a sampling rate synchronous with the motor driving the rotation. Two contiguous sets of samples, each set spanning several revolutions of the part, are stored. The X and Y components of the unbalance signal are calculated for each sample set and the actual rotation rate of the part is calculated from the assumed rate and any difference in the phase angle of the unbalance location between the first and second sample sets. These calculations are performed during a calculation interval of predetermined length which follows the sampling.

Abstract: A capacitive measuring system for measuring the distance between two relatively movable parts based on measurement of capacitative charge comprising a measuring sensor which forms one plate of the capacitor whose gap is to be measured. With the position of the sensor face in the fixed part of casing being known, the plate distance of the gap capacitor provides a direct measure of the gap.

Abstract: Optimization of running conditions of an automobile wheel is achieved by matching (readjustment of tire relative to rim) after two measuring runs of the tire/rim assembly and in which the static and dynamic unbalance vectors of the tire and rim include coefficients of influence on said running conditions.

Abstract: The present invention relates to an apparatus for detecting and indicating the balance of a rotating body such as a grinding wheel, a spindle or the like in a machine tool such as a grinding machine. The apparatus comprises an original-point detecting means for detecting an original point on the rotating body, a vibration detecting means for detecting vibration caused by an unbalanced condition of the rotating body, an arithmetic means for computing, from the detected vibration, a deviation of said rotating body in each of a plurality of index positions on the rotating body which are angularly spaced from said original point as a reference, a deviation display means for displaying the maximum value of the deviations, and an unbalanced position indicating means for indicating one of the index positions based on the computed deviations.

Abstract: An unbalance measuring station (1) is disclosed toward which a rotor to be balanced is carried by a transport system (7). The station (1) contains an unbalance measurement unit (10) as well as devices (11, 12) for loading the rotor (6) into the unbalance measurement unit. The unit is essentially arranged above the plane of the path of movement of the transport system (7). The unbalance measuring station (1) is particularly suited for use in connection with transfer and assembly lines.

Abstract: Apparatus and methods for use in measuring the uniformity of a body such as a tire, wheel or the like wherein a waveform related to the uniformity of the body is digitally sampled to acquire a series of data samples, each of which is correlated with a respective physical location on the body. According to a first aspect of the invention, a non-repetitive error component of the waveform is corrected for by sampling the same location on the body at two different times and determining the difference between the corresponding data samples. A part of the total difference is allocated to each of the data samples in the series according to a predetermined methematical function which at least approximately describes the non-repetitive component of the waveform. The part of the difference allocated to each sample is then subtracted from it to obtain a corrected series of data sample.

Abstract: A method and apparatus for the automatic balancing of workpiece having diverse surface geometry is disclosed. The balancing machine of the present invention provides for computer numerical controls in the balancing and material removal operations. The processes provide for alternative methods of material removal and further provides for the balancing operation to be self-calibrating and self-programming.

Abstract: Disclosed is a system and method for accurately balancing a wheel/tire assembly. The assembly is mounted onto a shaft of a dynamic wheel balancer to rotate therewith. The shaft and wheel/tire assembly are spun while the balancer senses and stores a first set of information (readings) indicating imbalance. Next, the wheel/tire assembly is released and reoriented at a different angle, for example 180 degrees, on the shaft of the balancer, followed by respinning the wheel/tire assembly while the balancer takes a second set of readings indicating imbalance under these changed conditions. The values of both sets of readings are stored and then compared to note the difference therebetween. The difference represents a measure of the aggregate actual and "apparent" imbalance. For example, if the reorientation is 180 degrees, then the difference will be twice the actual imbalance. If the reorientation is less than 180 degrees, then the difference will be proportionately less than twice the actual imbalance.

Abstract: A system for balancing rotating members comprising a laser head which emits a laser shot in response to a laser control signal to remove material from the rotating member. The laser control signal is produced by a computer which is responsive to a plurality of signals representing vibration of the rotating member and influence coefficients from a memory device. The computer applies less than a calculated number of laser shots at each targeted location of the rotating member and then applies this reduced number sequentially to all targeted locations while calculating whether the vibration signals fall below targeted levels and, if so, discontinuing removal of material by the laser.

Abstract: A method and system for measuring the dynamical behavior of an elongate body which has a floating electrical potential and only forms a total capacitance with its environment and which has a longitudinal axis about which the body rotates, which method includes a contact-free capacitive measurement of changes in the position of the body transverse to the longitudinal axis by means of at least two measuring probes each disposed to form with the body a respective capacitor having a capacitance value corresponding to the distance between the probe and the body, the measurement being performed by: applying to each measuring probe a respective alternating current signal having a frequency selected such that the frequency of the signal applied to each probe differs from that applied to each other probe by at least a selected frequency difference value; deriving from each probe an output signal having an amplitude representative of the capacitance value of the capacitor formed by that probe with the body; and passing

Abstract: The wheel (3) to be balanced is mounted on a rotatable shaft carried by two spaced bearings (6, 4) provided with force sensors ( 8, 10). Two standard weights are mounted on the wheel rim at two points spaced angularly apart. The sensors (8, 10) signal the forces exerted on the bearings by the rotation of the wheel equipped with said weights. The weights are then removed and a new measurement ofthe forces exerted on the bearings is made. The values and the positions of the correcting weights to be placed on the wheel are then determined from the characteristic relationship of the wheel-apparatus assembly obtained by comparison of the results of these two measurements.

Abstract: The present invention provides a universal balance machine which can be utilized as a hard or soft balancing machine. Since the stiffness of the machine suspension is easy and readily changed, hard and soft balancing may be done on the same machine.

Abstract: Method and apparatus are described for bringing a rotating body, set in rotation by a drive, to a standstill as the conclusion of a work cycle. The rotating body may be placed in bearings in a balancing machine where it is investigated for unbalance. Characteristic values for the drive and the rotating body obtained during the acceleration phase are utilized in conjuction with one another for purposes of stopping the rotating body at an exact and specific position for machining purposes at that position on the surface of the rotating body.

Abstract: A machine and method for conveniently dynamically balancing heavy rotational members such as large vehicle wheels is disclosed. The machine employs a horizontal rotatable shaft that is movable vertically so as to align and engage the center of the member as it stands vertically in the ground. Thereafter the shaft is raised vertically until the member clears the ground and is rotatable for balancing. In preferred embodiments the balancing mechanism is manually powered and detachable from the machine's base for transport and the base is constructed with its vertical member angled so as to preload and stress the base by the weight of the member and eliminate play in the base. The machine offers portability and transport advantages.

Abstract: The balancing machine comprises a shaft (2) mounted on a frame (1) by means of two bearings (3, 4), under each of which a force sensor (5, 6) is mounted. The shaft (2) is driven by a motor (10) and a chain transmission. The chain (16) of this transmission has a pulling side which is taut and at right angles to the plane passing through the axes of sensitivity of the sensors (5, 6), while its driven side is slack.

Abstract: A magnetic axis is imparted to an object which effects three-dimensional rotational movement. The magnetosensitive semiconductor elements are disposed in the directions of three axes or two axes of a space determined for the object in such a manner that the elements are not in contact with the object. Any variation in direction of the magnetic axis resulting from movement of the object is detected by the magnetosensitive semiconductor elements. The detection signals from the magnetosensitive semiconductor elements are electrically processed so that the three-dimensional rotational position and movement of an object may be detected without contact and continuously.

Abstract: A tire balancing machine in which the tire is mounted on an axle which is pivotally mounted relative to a road wheel while maintaining the axis of rotation of the tire parallel to the axis of rotation of the road wheel, the tire being spring loaded against the road wheel to simulate the weight load borne by the tire in normal use and the road wheel driven at a speed to rotate the tire at its intended operating speed, sensors being provided to measure the magnitude and location of the horizontal and vertical asymmetrical forces developed at the tire patch, the force measurements being utilized to determine the location and amounts of weight to be applied to the wheel rim to offset the asymmetrical forces generated by the tire in use.

Abstract: Method and apparatus for taking into account position inaccuracies of attachment surfaces for later attachment of components, that possess mass on a rotor, such as a crankshaft with crankpins, during balancing of the rotor. The attachment surfaces such as crankpins function as sites for the later assembly of components that possess mass. Differences between the ideal and actual positions of each attachment surface are determined and are taken into account during the balancing procedure.

Abstract: A light weight, low speed, low cost dynamic balancing machine useful for wheel balancing includes a light weight base, sensors for detecting unbalanced signals and attendant noise, and a low energy drive employing a small electric motor driving elastic belts for rotating the body to be balanced.

Abstract: A method and apparatus for balancing of a motor armature and fan coupled thereto is disclosed. The apparatus includes a pair of spaced end brackets for supporting an armature of the motor and the fan for rotary movement. At least one motor bracket is coupled between the end brackets and includes means for detachably mounting a set of field coils for the motor thereon. The motor bracket further includes a recess therein which, when the set of field coils is detached from the motor bracket, exposes the armature to permit the armature and fan to be rotated as a unit so that the balance of the unit can be determined. The method and apparatus are particularly adavantageous for balancing a motor-fan system in which the motor is of the split-field coil type.

Abstract: A method of and apparatus for balancing a rotary body is disclosed. The apparatus includes an unbalance detection unit which rotates the body in first and second spaced bearings, the location of the first and second bearings defining first and second bearing planes, respectively. The forces developed by rotation of the body are sensed at the first and second bearing planes and the forces about the first bearing plane are summed to determine the weight and angular location of a mass compensation which, if effected, would substantially statically balance the body. An iterative technique is utilized which determines the axial location of the mass to be removed or added which would reduce to a minimum the dynamic unbalance of the body. The body is then passed to an unbalance correction unit which removes or adds the mass at the determined angular and axial locations to minimize the static and dynamic unbalances.

Abstract: A method and apparatus for measuring vibrational forces emitted by a reaction wheel assembly during rotation of its rotor includes a low mass carriage (12) supported on a large mass base (10). The carriage (12) is in the form of an octagonal frame having an opening which is adapted for receiving the reaction wheel assembly (W) supported thereon by means of a mounting ring (22). The carriage (12) is supported on the base (10) by means of air bearings (A) which support the carriage in a generally frictionless manner when supplied with compressed air from a source (50). A plurality of carriage brackets (34) and a plurality of base blocks (30) provide for physical coupling of the base (10) and carriage (12). The sensing axes of the load cells (B) are arranged generally parallel to the base (10) and connected between the base and carriage such that all of the vibrational forces emitted by the reaction wheel assembly (W) are effectively transmitted through the sensing axes of the load cells.

Abstract: Method of dynamic balancing of rotating machines in assembled condition, the machines being symmetrical to their center of weight. The effective value of the speed of radial vibrations arising from unbalance when the machine is running at no-load speed and is vibro-isolated from the surrounding media are measured by measuring the relative acceleration phases of the vibrations. Correction masses are estimated for each balancing plane by dividing the measured effective speed values by a constant characterizing the machines of a given type, which is determined beforehand. When the machine is dismantled, correction masses are placed in the balancing planes at angles obtained from the determined relative acceleration phases plus 270.degree. they added along the directional rotation of the rotor of the machine. These angles are measured according to a mark on the shaft of the machine.

Abstract: A vibration monitoring system analyzes tachometer signals of a rotating engine to ascertain the period of rotation from which sampling pulses at predetermined intervals can be generated. Sampled accelerometer data is processed by a nonrecursive tracking digital filter to determine peak velocity or displacement of rotating engine. In a different operating phase, apparatus determines the rotational location of the peak relative to an index or reference point on the rotating engine. The magnitude and location of the peak can be signaled for subsequent correction of the imbalance. The rotational velocity is monitored so that changes in velocity during a measurement invalidate the results and cause a repetition of the measurement cycles.

Abstract: Wheel balancing apparatus includes a shaft for rotating the wheel. Sensing devices are provided on spaced bearings for the shaft to obtain dynamic and positional data concerning the imbalance of the rotating wheel. A feeler arm is mounted so as to be angularly and axially slidably movable about and along an axis parallel to the wheel axis, in such a manner that contact means on the arm are brought successively into contact with opposite edges of the wheel disc. Potentiometers are associated with the arm to sense its axial and angular position when the contact means are in contact with the wheel edges. The radius and thickness of the wheel can then be derived from these positions.

Abstract: Dynamic unbalance of a rigid rotor is corrected by machining the rotor in a direction parallel to the rotor axis of said rotor by subtracting or adding weights corresponding to a corrective weight in two planes for compensating initial unbalanced vectors corresponding to correction angle directions and corrective weights in the planes. Prior to effecting the machining, center of gravity position of a corrective machining weight is calculated for effecting corrective machining in the axial direction; the corrective machining corresponds to the corrective weight. The initial unbalanced vectors in the two planes are corrected into unbalanced vectors in new planes respectively including the centers of gravities of the corrective machining weights determined during the calculating step. Correction angular positions and corrective machining weights around the respective planes are obtained by repeating the calculating and correcting steps.

Abstract: Asymmetries of rotatable members such as aircraft propellers can be balanced out by the careful addition of counterweights at proper positions on the members. An accelerometer coupled to the mounting of an unbalanced rotating member produces a signal containing a component indicative of the unbalance. This signal would be useful for helping in the balancing process but it may also contain noise components from which the useful component has to be extracted without too much alteration. A fixed frequency band-pass filter could be used but the results then have to be manually corrected if the actual frequency varies from that associated with the filter or a manually turnable filter could be used but then of course the filter has to be tuned for each test.

Abstract: A first processing circuit receives signals from a vibratory acceleration and a speed of rotation and position sensor and comprises integration and filter means for providing a signal (sb) representative of the amplitude of any untrue running. A second processing circuit receives the output signal (sw) from the speed of rotation and position sensor and the signal (sb) and includes means for determining the phase difference between the signals (sw) and (sb). A memory (33) stores information representative, for different revolving systems and/or test conditions, of the difference between the measured phase difference and the angular position of an imbalance causing untrue running with reference to an origin on the revolving system. Appropriate information is read from the memory and combined with the measured phase difference in response to the actuation of selection means to provide an accurate output of the angular position of any imbalance causing untrue running.

Abstract: A system for dynamically balancing a wheel utilizes low speed (preferably 50 to 100 rmp) rotation of the wheel that can if desired be provided manually. In manual operation as the rotation is imparted to the wheel by an operator, the rotational speed of the wheel is measured, and an indicator notifies the operator when sufficient rotational speed has been imparted to the wheel to enable a balancing operation to be carried out. Thereafter the wheel is allowed to coast and decelerate until the sensed forces have adequately settled out, then the forces of imbalance transmitted by the rotatable shaft are measured. When the measurements are obtained, any detected imbalance of the wheel is displayed on a suitable indicator mechanism.

Abstract: An apparatus for measuring and monitoring the angular velocity of the shaft of a rotating machine. In this apparatus, a plurality of sensors is positioned adjacent the shaft of the rotating machine for generating sequential pulses with periods proportional to the angular velocity of the shaft. The pulses are generated at intervals such that, during the period between adjacent pulses from one sensor, pulses are generated by each of the other sensors. An oscillator is provided for generating reference pulses at a predetermined pulse repetition rate, and a plurality of counting devices are coupled to respective sensors and to the output of the oscillator for counting the pulses generated by the oscillator. An averaging and reciprocal circuit is coupled to the output terminals of the counting devices for obtaining the average of the counting device outputs and then generating the reciprocal of the average value.

Abstract: A dynamic electric wheel balancer for measuring the imbalance condition in a vehicle wheel and indicating the position and correction weights required for balancing the wheel in one or two planes. The wheel balancer contains a rotating shaft in order to make the dynamic measurements. The shaft is freewheeling during measurement and is brought up to a predetermined minimum r.p.m. value through a motor and clutch arrangement. In order to take the measurements, piezoelectric sensors are used to measure the vertical force components exhibited by the imbalance condition of the vehicle wheel secured to the rotating main shaft. The measured force components are converted into digital form. The balancer finds the definite integral of each of the forces generated by the piezoelectric transducers and uses the cross correlation data generated by these integrations to find the zero crossing points and the peak determinations.

Abstract: An apparatus for determining the imbalance in a rotating object has a drive means for rotating the object about an axis. Transducers measure the force of imbalance of the rotating object, with each transducer producing an electrical signal in response thereto. Electronic means receives the signals from the transducers and calculates the imbalance in the object. Drive means is directly coupled to the rotating object, such as a tire, with the drive means in the hub of the wheel on which the tire is mounted. Cantilever support means having a substantially planar surface provides support for the drive means onto the transducers in the frame of the apparatus.

Abstract: A procedure and a device are provided for determining the correlation between the unbalance of a rotor in at least one correction plane thereof and the measurement signal generated by such unbalance at one or more of the rotor supports. The vibration signals of the rotor are measured at different bearing support stiffness.

Abstract: A dynamic balancing machine having a rotatably driven mounting shaft for articles to be balanced has a fixture upon which known weights are mounted at two known calibration planes ralative to the shaft. Data taken by force sensors coupled to the shaft during two shaft spins with the known weights mounted in each calibration plane are used to calculate sensor output correction factors applied to unbalance data taken during the spin of a mounted unbalanced article for a pair of unbalance measurement planes spaced along the shaft. The unbalance calibration and measurement planes are axially displaced along the shaft from the location of the force sensors. The disclosure is directed toward apparatus and method for obtaining machine calibration.

Abstract: In accordance with the invention, a magnetic field sensor is disposed on a stationary part of a centrifuge near an annular member of a rotor and is adapted to detect those variations in a gap which exists between the annular member and the sensor. The variations in the gap arising from deflection and/or precession of the rotor axis.

Abstract: A dynamic vehicle wheel and tire balancing system with manual rotation of the shaft to which the wheel and tire is attached. A computer within the system receives entered premeasured values of wheel dimensions and are in response to the output of a rotational speed sensor determines a proper rotational speed of the shaft at which point it automatically decouples the manually operated crank from the wheel shaft so that there can be no externally applied disturbances for the subsequent measurements of imbalance. Twin spaced transducers along the shaft determine the wheel runout attributable to imbalances in both inner and outerwheel rims and the computer provides output signals indicative of the correct balance weight and the mounting positions of the weights on the wheel rim.

Abstract: A method of and a system for reducing an excessive amplitude of unbalance vibration occurring in a rotor by actually measuring and comparing the unbalance vibration amplitude of the rotor with a desired level for judgement as to whether the desired value is exceeded, selecting a certain correction plane combination in accordance with the measured unbalance vibration amplitude. A correction mass to be added to the rotor is calculated using an influence coefficient corresponding to the selected correction plane combination, assuming that the correction mass is added to the rotor, estimated residual vibration amplitudes and root mean squares thereof are calculated at respective correction plane position combinations each having at least any two of positions of a plurality of correction planes on the rotor.

Abstract: An unbalance measurement device is provided for a balancing machine for determining the unbalance of a rotor according to position and magnitude. The balancing machine has a drive motor, transducers, a spindle supporting the rotor to be balanced, and an increment disc fixed to the spindle. Filter circuitry for analog signals is provided for the purpose of reducing extraneous signals by means of a filter whose mid-frequency is controlled by a high control frequency. Due to this filtering, changes in the rotational frequency of the rotor to be balanced do not influence the determination of the position of the unbalance. In addition, in the case of correction in several planes, interference of the measurement in one plane caused by the preceding measurement in the other plane is prevented.

Abstract: A dynamic electric wheel balancer for measuring the imbalance condition in a vehicle wheel and indicating the position and correction weights required for balancing the wheel in one or two planes. The wheel balancer contains a rotating shaft in order to make the dynamic measurements. The shaft is free wheeling during measurement and is brought up to a predetermined minimum r.p.m. value through a motor and clutch arrangement. After measurements have been made, a solenoid actuated brake, which takes advantage of the force factors associated with a flywheel forming part of the main shaft, brings the rotating shaft to a halt. Prior to taking the measurements, the wheel balancer is calibrated by employing a known weight located at a known position on a face plate forming part of the main shaft. In order to take the measurements, piezoelectric sensors are used to measure the vertical force components exhibited by the imbalance condition of the vehicle wheel secured to the rotating main shaft.

Abstract: A method and an apparatus for marking the amount and location of unbalance on a rotatable body, such as a vehicle wheel. The apparatus uses a conventional system for determining the amount and location of unbalance in the body. A marking device is actuated to mark one or both sides of the body with a mark or marks representative of the amount and location of determined unbalance. The beginning and ending points of the mark can be representative of the beginning and end points of the correction mass to be applied to the body. The marks also can be representative of the predetermined weights of correcting masses to be applied to the body. Application of marks representative of the amount and location of unbalance to the bodies provides a visual indicator that facilitates subsequent check of the correct application of unbalance correction masses to the body.

Abstract: A workpiece to be balanced, which during a measuring run is driven or rotating in the coupling-free mode and is provided with a mark for contact-free pick-off to generate a reference signal, is to be positioned subsequently, that the unbalance is at a predetermined location below a marking or correcting device. To this end pulse sequences synchronous with the supporting rollers carrying the workpiece are generated. The pulses are counted in a counter between the reference signal and an unbalance position signal derived from the unbalance signal. For the positioning the counter is counted down to zero by these pulses starting from the reference pulse. When the counter passes through zero the unbalance is in the plane of the pick-off device for detecting the mark.

Abstract: An apparatus for balancing a body to correct for unbalance determined during a measurement run on a balancing machine. The body to be balanced is rotated at a measuring speed by compressed air and the unbalance is determined. A braking device then is applied to the body to brake the body and rotate the body at a low speed. When a predetermined portion of the body is located in a desired angular position, a stopping device, such as a pawl, is actuated to stop rotation of the body. Appropriate mass is then added to or removed from the body to correct the unbalance. If necessary, the pawl is released, and body is incrementally rotated so that unbalance can be corrected on several portions of the body. The apparatus, instead of balancing the body, is usable to mark the body as to the location of unbalance.

Abstract: A procedure for determining the magnitude and angular position of the unbalance of a rotor is described together with an apparatus for accomplishing same. A series of impulses are generated as the rotor rotates, and these impulses relate to the periphery of the rotor. When the unbalance is determined the particular impulse number at the time of that determination is noted, and such impulse is representative of a particular point on the periphery of the rotor.

Abstract: A shaft vibration evaluator employs measured displacement of a shaft in the vicinity of a bearing together with known or measured shaft eccentricity to calculate the dynamic bearing load so that damaging loads can be avoided. Shaft vibration or motion is assumed to be elliptical having major and minor axes which are inclined at angles with respect to the bearing displacement sensors. The magnitude of the major and minor axes and the angular displacement are calculated from the measured parameters and provide one set of inputs to the load calculator. Bearing eccentricity can be calculated from a knowledge of shaft speed, lubricant temperature and known bearing geometry. For a given eccentricity, a set of four damping coefficients and four spring coefficients of the bearing may be derived. These coefficients are the remaining inputs to the dynamic load calculator.

Abstract: A method and apparatus for determining and indexing the angular location of unbalance of a rotatable body. Such unbalance is determined by mounting the body on a balancing machine and rotating the body to obtain an unbalance measurement. The method and apparatus provide for the subsequent rotation of the body to a correction position over the shortest possible distance.

Abstract: An off-the-car wheel unbalance measuring system has a rotationally driven wheel mounting shaft supported in a pedestal together with a pair of force transducers mounted in the pedestal adjacent to and spaced along the shaft. The force transducers are coupled mechanically to the shaft and provide periodic electrical output signals indicative of unbalance forces transmitted through the shaft when the shaft is driven rotationally. The angular position of the shaft is monitored with respect to an angular reference position at a predetermined number of angular increments during each full revolution of the shaft. The transducer output signals are converted in electrical circuitry within the system to digital form, and a multiplication operation is performed on the digitized signals at each angular increment using sine and cosine representative factors corresponding to that particular angular increment.