Abstract: Systems and methods involving reconfigurable rotating masses are disclosed. One embodiment may take the form of a system having a motor and coupled weights attached to the motor. Operation of the motor rotates the coupled weights and the weights are dynamically reconfigurable to change the location of the center of mass relative to an axis of rotation.

Abstract: The present invention describes a system for taking the necessary energy for operating the electronic circuit for monitoring a bearing (A) directly from the rotation movement, namely from the kinetic energy of the bearing i.e by energy harvesting or scavenging. All information read on board the bearing (A) by the sensors (4a, 4b) are sent through radio with a wireless communication system to an external data collecting and processing unit (6), that is able to evaluate and communicate the status of the bearing (A) being analyzed. The preferred system embodiment provides that the generator (1) bases its operation on the gyroscope (or Coriolis force) effect a circuit (7) for accumulating the necessary energy for turning the system on.

Abstract: The present invention describes a system for taking the necessary energy for operating the electronic circuit for monitoring a bearing (A) directly from the rotation movement, namely from the kinetic energy of the bearingi.e by energy harvesting or scarvenging. All information read on board the bearing (A) by the sensors (4a, 4b) are sent through radio with a wireless communication system to an external data collecting and processing unit (6), that is able to evaluate and communicate the status of the bearing (A) being analysed. The preferred system embodiment provides that the generator (1) bases its operation on the gyroscope (or Coriolis force) effect a circuit (7) for accumulating the necessary energy for turning the system on.

Abstract: A vibrating plate for compacting soil comprises an upper mass; a lower mass, which is elastically coupled to the upper mass and which has at least one soil contact plate, and; a vibration generator device that acts upon the soil contact plate. The vibration generator device comprises at least four unbalanced masses that can each be rotationally driven about a rotation axis, the rotation axis of at least two of the unbalanced masses being arranged at an angle to the rotation axes of the other unbalanced masses. One of the unbalanced masses depicts a reference unbalanced mass that does not require its own phase adjusting device. On the other hand, a separate phase adjusting device is assigned to each of the other unbalanced masses, enabling the phase position of these unbalanced masses to be individually adjusted with regard to the reference unbalanced mass.

Abstract: A vibrator includes a vibrating table; a plurality of driven unbalanced shafts disposed within the vibrating table and arranged in pairs; and a plurality of unbalanced bodies. A separate unbalanced body is connected to each unbalanced shaft. The unbalanced bodies can assume various vibrating frequencies and angular positions. An adjustment device varies the vibrating frequencies and angular positions of the unbalanced bodies relative to one another. Each shaft is driven by a separate motor; the motors are adapted to rotate in synchronism with one another at a predetermined rotational speed. The adjustment device includes an electronic controller for regulating each of the motors.

Abstract: A controlled vibration experiment device having a vibration model structure to simulate actual mechanical vibration and to monitor and analyze the vibration by a computer monitor. The device has a base plate, a supporting frame, a T-shaped sliding rail, a servo motor, a connecting piece and a decoder with a rotatable shaft. The vibration produced is changed to an electrical signal and input to the computer to display the various type of waveforms. The vibration phenomena is then analyzed by a computerized monitor.

Abstract: A mounting stand in a balancing machine mounting assembly includes a stationary mounting block and a mount for a rotary member to be balanced. The mount is supported on the mounting block by two parallel springs capable of oscillating movement in a mounting plane in the measurement direction. The mounting stand further has at least one measurement value pick-up sensor operatively disposed between the mounting block and the oscillatable mount for detecting oscillation of the mount produced by an out-of-balance rotary member and to supply corresponding measurement signals. A rotatable adjusting unbalance weight of a known magnitude is mounted to the oscillatable mount and can be selectively brought into operation to cause oscillatory movement of the oscillatable system, to perform a calibration.

Abstract: A method is disclosed for providing optimal compaction of various materials by controlling the vibration amplitude of an adjustable amplitude vibratory roller. The vibration amplitude is automatically reduced when excessively high jolting forces are sensed by transducers carried by the roller or its frame. The apparatus for carrying out the method includes a continuously adjustable eccentric element in the vibratory roller, at least two signal transducers mounted on the roller drum or frame and axially separated, to generate signals representing the vibrational movement of the roller. A regulating system responsive to the signals from the signal transducers reset the adjustable eccentric element to vary the vibration amplitude and provide optimal compaction.

Abstract: The dynamic properties of a machine are defined by its kinetic energy, potential energy and dissipation functions. The machine is also identifiable by the nonviscous friction therein. These properties form the basis for the dynamic analysis of any machine. When the response of a single degree of freedom machine is observed while being driven by a forced periodic input torque, information is obtained whereby these functions together with the nonviscous friction characteristic may be determined. The apparatus and method by which such determinations may be made have applications in machinery development, quality control and diagnosis.

Abstract: A hammer-type device is driven by a cam and spring arrangement in reciprocating motion to strike a moving train wheel for producing vibrations therein which are used to detect defects in the wheel.

Abstract: A method of determining the phase angle of a vibrating mechanism using line segments of selected angles. The motion of the line segments on the vibration mechanism is observed and the phase angle of the vibratory mechanism is determined using information from the observation.

Abstract: A rotating eccentric weight apparatus and method for generating coded shear wave signals for use in seismic exploration. The apparatus includes a rotatable eccentric and a position sensor capable of detecting each instant that the eccentric passes a particular angular position about its axis of rotation and generating a code signal for use in correlating the raw seismic data obtained. In one embodiment, the apparatus includes an outrigger shovel which transmits a sinusoidal shear wave signal generated by the rotating eccentric while the rest of the apparatus is caused to alternately decouple from and impact against the earth surface to transmit a coded train of pressure wave impulses into the earth.

Abstract: Apparatus and method for measuring the crevice gap clearance between the tubes and tube supports in a heat exchanger includes setting the tube into vibration until it impacts against the tube support plate and determining by accelerometers mounted on the tube the distance the tube has moved.

Abstract: A method and an apparatus is disclosed for measuring weighing and/or mass of an object. The object to be measured is subjected to an input frequency signal supplied to a piezoelectric crystal. Another piezoelectric crystal supporting the object is caused to vibrate in response to the input frequency signal and the mass and/or weight of the supported object. This second vibrating piezoelectric crystal will then produce a frequency output signal, whose amplitude is a function of the mass (and/or weight) of the object being measured. The frequency of the input and the output signals are substantially the same.

Abstract: An apparatus for use in the medical diagnosis of human and other bodies and also for use in the automatic machine interrogation of individuals for identifying persons such as those seeking credit or admittance to a security area. Oscillatory wave energy, preferably a sonic signal, is applied with a selected polarization to a first part of a body. The polarization of the wave energy transmitted through a portion of the body is detected at a second part of the body. Data representing the shift in polarization is stored for subsequent comparison to a polarization shift which is subsequently measured by the same steps. Comparison of the data representing the two polarization shifts can be used for quantitative and qualitative medical diagnosis as well as for an automatic machine decision whether the polarization shifts are sufficiently similar that they were derived from the same individual. The use of multiple frequencies permits the derivation of a polarization shift characteristic over a range of frequencies.

Abstract: Apparatus responsive to the pressure of a fluid contained in or surrounding a stiff but resilient hollow body comprises a stiff, but resilient ring mounted concentric with the body by means of four equi-spaced radially extending stiff struts. Electromagnetic means is provided for exciting natural vibrations of the ring at a resonance frequency, which will be dependent upon the pressure of the fluid in the body. Means is provided for measuring the frequency of vibration, enabling the pressure of the fluid to be determined, e.g. from a pressure-frequency calibration curve for the apparatus.

Abstract: A system responsive to pressure differential is provided for non-destructive testing of the bonding between a face sheet and the attached core of a laminated or like composited structure, including an internally evacuated transducer arranged to glide easily over the surface being scanned while maintaining a constant or pulsating vacuum. Displacement of the face sheet is detected by the transducer which generates a signal indicative of the extent of the defective bond.

Abstract: This invention relates to an automatic method and apparatus for quick and convenient testing of one or more geophones of a geophysical data acquisition system through the generation and analysis of the impulse response characteristics of such geophones. In particular, geophone response characteristics related to first and second adjacent absolute peak amplitudes associated with the damped equation of motion of the geophone coils are detected and digitally indicated in a surprisingly accurate manner, irrespective of whether or not the testing is carried out in a laboratory or field environment.

Abstract: A system for measuring the vibration frequency of a vibrating object useful for the adjustment of the vibration frequency of a piano string or like vibrating objects. In this system, the vibration of the vibrating object is converted to an electric signal, based on which signal is sought the difference between the vibration frequencies of any two adjacent harmonics of the vibrating object, i.e. the fundamental vibration frequency of the vibrating object is sought. The electric signal is led to a counter via a voltage-controlled variable band-pass filter. The middle frequency of the pass-band of this filter is controlled by a sweeper and varies continuously. For each agreement of this middle frequency of the pass-band with any one of the harmonics, the output of the filter presents a peak. The frequency corresponding to each peak is detected by a counter. The fundamental frequency is calculated from the difference between the frequencies corresponding to any adjacent peaks of the outputs of the filter.

Abstract: Apparatus for non-destructively monitoring the bonding quality of an ultrasonic bonding system by detecting the amplitude deviation of a vibrating bonding tool between the vibration amplitude thereof in the freely vibrating (no-load) condition and the vibration amplitude during an ultrasonic bonding operation.

Abstract: An instrument for determining the complex mechanical response of samples incorporates two parallel sample arms each pivotally mounted at their central portion by flexure pivots of precisely known spring constants. The sample is mounted on one end of each. An electromechanical driver acts on the other end of one arm to maintain the arms and sample in mechanical oscillation about the pivots. A displacement transducer senses the mechanical motion. A feedback amplifier between the displacement transducer and the driver maintains the oscillation at a constant amplitude and at a resonant frequency determined primarily by the sample. With this arrangement the driver and displacement sensor are removed from the sample and its usual thermal chamber. This improves the stability of the instrument. At the same time the arms are dynamically balanced about the pivots and hence are relatively insensitive to vibrational upset.

Abstract: A method and apparatus for analyzing a damped structural specimen permits undamped mobility values and modal accelerations to be determined. The specimen is excited by vibrations in conventional fashion, and both actual and modified mobility response curves or characteristics are determined from measured responses. The modified mobility curve is produced by adding to a signal representing the vibratory force applied to the specimen an artificial force signal generated electronically. The generated artificial force signal simulates the addition or subtraction of mass at the point on the specimen where responses are measured. An undamped mobility value of the damped specimen is determinable at resonant frequencies indicated by the modified mobility curve. From the undamped mobility value and the corresponding frequencies, it is possible to determine modal accelerations for the various vibratory modes of the specimen.

Abstract: Three embodiments of an improved photo acoustic cell for use in analyzing solid and quasi-solid samples are disclosed. Each cell includes a sample holding chamber having one wall or portion of one wall thereof made from a light transparent material. The sample holding chamber in each embodiment is connected to a microphone by a thin tube which renders the cell, which includes the chamber tube and microphone, an acoustical resonant structure at a frequency within the response characteristics of the microphone. In one embodiment, means are disclosed for pressuring the inside of the cell as well as equalizing the pressure on the outside of the tube. In a second embodiment, the sample to be analyzed forms a portion of the cavity walls and means are provided for reducing the pressure in the cavity to hold the sample securely to the remaining structure for defining the cavity. In this embodiment a fiber optic element brings the light into the chamber.

Abstract: A previously charged capacitor is discharged through a coil having a core situated in the vicinity of the steel tooth. The discharge creates a surge of magnetic circulation whose attractive forces cause a bending of the steel tooth which then executes flexural vibrations. A sensor senses the flexural vibrations and furnishes an electrical signal whose amplitude and/or frequency characteristics are examined to detect defects in the tooth.

Abstract: A method for the medical diagnosis of human and other bodies and also for use in the automatic machine interrogation of individuals for identifying persons such as those seeking credit or admittance to a security area. Oscillatory wave energy, preferably a sonic signal, is applied with a selected polarization to a first part of a body. The polarization of the wave energy transmitted through a portion of the body is detected at a second part of the body. Data representing the shift in polarization is stored for subsequent comparison to a polarization shift which is subsequently measured by the same steps. Comparison of the data representing the two polarization shifts can be used for quantitative and qualitative medical diagnosis as well as for an automatic machine decision whether the polarization shifts are sufficiently similar that they were derived from the same individual. The use of multiple frequencies permits the derivation of a polarization shift characteristic over a range of frequencies.

Abstract: Method for determining, non-destructively, degradation of certain physical roperties of textile materials wherein a sample of the textile material is held under tension and caused to ring to generate acoustic signals and the frequency of the acoustic signal is compared with the frequency generated from a control of the same material, with any significant difference in frequency of response of the sample as compared with the control indicating a change in physical property.

Abstract: A method of testing wear-resistance of articles which comprises measuring the rate of propagation of ultrasonic oscillations in a reference article which has the lowest admissible wear resistance. The rate of propagation of ultrasonic oscillations in the articles being tested is compared with the rate in the reference article. The reference article is placed into a liquid in the suspended state and the articles being tested are placed into the same liquid. Those articles, which ascend to the surface, are rejected.

Abstract: A method for measuring the axial force exerted on a body to be measured by applying two ultrasonic frequencies respectively having a transverse-wave vibration mode and a longitudinal-wave vibration mode to a body on which an axial force is exerted, measuring the natural frequencies of the body in the transverse-wave and longitudinal-wave vibration modes, obtaining the result of a computational operation (e.g., the result of a subtraction) on the measured natural frequencies, and measuring from this result the axial force exerted on the body in accordance with the predetermined result-versus-axial force calibration values.

Abstract: Nuclear reactor fuel rod leakage is determined by measurement of vibrational characteristics of a resilient, flexible means sealed within the upper end caps of the fuel elements. The flexible means, which is preferably a metallic diaphragm, is set into motion and the vibration measurements are made by a special tool which fits over the end cap of the fuel element to be tested.

Abstract: Surface properties, such as, hardness, of a test piece are determined by holding a mechanical resonator, for example, in the form of a sensor rod against a surface of the test piece with a static force sufficient to maintain steady contact with the test piece surface at a contact surface on the sensor rod shaped to provide an increasing area of contact with increasing plastic and/or elastic indentation or deformation of the test piece surface, exciting the test piece into vibration with a frequency which is varied so that the vibrations transmitted from the test piece to the sensor rod will cause the latter to attain a state of resonance, for example, as indicated when a maximum amplitude of the vibration of the sensor rod is sensed, measuring the amplitude of vibration of the excited test piece at a region of the latter which is adjacent to, but outside of the area of contact of the test piece with the contact surface on the sensor rod, for example, by means of an auxiliary sensor, and further varying the fr

Abstract: The invention refers to a measuring circuit for determining the properties of a workpiece, particularly hardness, using the contact impedance method in which a probe resonating at an ultrasonic frequency provided with a workpiece engaging tip is utilized. The measuring circuit uses digital counters for producing a digital count which is the difference between the free-resonant frequency of the test probe and the resonant frequency of the probe when the probe is in forced contact with the workpiece. A read-only-memory (ROM) converts the difference frequency count to a hardness value, such as Vickers or Rockwell. The disclosed arrangement obviates the need for zeroizing the circuit and, hence, is self-compensating in respect to drift and thermal stability.

Abstract: Resonant vibration is employed for imparting oscillations to a stressed wire, cable or metallic strip for the purpose of measuring its tension or for setting the vibrated member at a desired tension. A U-shaped magnetic resonator has an air gap to receive a stressed wire or cable and to impart vibrations thereto, the air gap being of such a width as to permit the received element to vibrate freely at its resonant frequency. The tension of the stressed element can be measured by varying the frequency of the resonator and noting when the condition of resonance exists or the tension of the element may be set by varying its tension while subjected to a steady predetermined pulsating magnetic flux field until the condition of resonance is noted. Either operation is performed in the absence of current flow through the stressed element.

Abstract: A sonic generator sends a collimated acoustical wave into the section of earth under test and resonance conditions are established depending upon the nature and depth of discontinuities in the path of the acoustical wave. These resonance conditions are monitored by observing and recording electrical relationship in the power supply section of the sonic generator.

Abstract: An electronic apparatus and method suitable for automatic machine interrogation of individuals for identifying persons such as those seeking admittance to secure areas or seeking an extension of credit. Acoustical wave energy is applied by an oscillator and transducer to the person's body, such as one end of an arm. Another transducer contacts another body part, such as the other end of the arm, to receive the body-transmitted energy. The frequency response characteristics of the body part are then detected by suitable correlation means to determine the amplitude and phase transfer functions. Comparison of a previously known transfer function of a person with a subsequently measured transfer function permits a machine decision whether the functions represent the same person.