Abstract: An ultrasonic probe has a piezoelectric vibrator composed of an array of piezoelectric vibrator elements, and an electrode plate having as many electrode patterns as the number of the piezoelectric vibrator elements. The piezoelectric vibrator elements and the electrode patterns are electrically connected to each other by an auxiliary electrode plate disposed therebetween. A method of manufacturing the ultrasonic probe is also disclosed.

Abstract: A system and method for nondestructively inspecting and monitoring materials that indicates the structural integrity of the material is disclosed. The inspection method includes the following steps. First, the material to be subsequently monitored, is tagged by dispersing a small amount of finely divided particles throughout the material. The tagged material is then applied in accordance with its application, such as adhesive material to two pieces to be joined to form an adhesive joint. When the adhesive joint or other material is to be inspected, the tagged particles are activated to cause an inherent structural resonance in the tagged material. The activation and structural resonance of the material is then monitored and measured with a probe. Finally, the structure resonance of the material is related to the structural integrity of the adhesive joint, the matrix-reinforcement interface integrity of a composite material, or the state of cure of a resin.

Abstract: Hot target ultrasonic measurement system in which an ultrasonic transducer for transmitting ultrasonic energy along a measuring path toward the hot steel ingot target receives a reflection echo of ultrasonic energy from the hot target along the measuring path, and electronic circuit for determining the range to the hot target from the time of transmission of said ultrasonic energy to the receipt of reflection of ultrasonic energy from said target. The temperature or speed of sound in the media in the measuring path is measured and used in the range measurement.

Abstract: An ultrasonic ground speed sensor has a single transducer which both transmits and receives ultrasonic signals. The sensor is mounted on a vehicle in alignment with the direction of the vehicle, the transducer having a built-in angle with the body of the sensor unit. The transmitted signal is clocked by a 16 MHz clock, with the signal received by the transducer selectively filtered and amplified. A temperature sensor is also used to determine the speed of the transmitted and received signal. A 64-cycle sample period is used, as well as multiple counters and a signal processor to increase accuracy and minimize erroneous readings. A drop-out detector and monitoring system sensor is also described. The vehicle speed is calculated from a Doppler-based formula as a function of both the sum and difference of the transmitted and received signal frequencies. Also disclosed is a gasket seal having leak holes for drainage from the interior of the sensor.

Abstract: An apparatus for inspecting a tire for structural defects as the tire is rotated on a stand comprises a movable transducer transmitter for directing a plurality of successive collimated bursts of ultrasonic energy against the tire surface, said bursts passing through the tire and forming inspection areas having the same diameter and overlapping each other as the tire is rotated during an inspection cycle. A movable receiver transducer located on the other side of the tire from the transmitter is constantly positioned to receive the collimated ultrasonic energy that passes through each inspection area. Coordination control elements are provided for moving the transmitter transducer and the receiver transducer from one side of the tire to the other generally parallel to its axis of rotation while successive ultrasonic bursts are directed through the tire as it rotates during each inspection test and while maintaining substantially the same distance between the transducers for each burst.

Abstract: The invention solves the problem of measurement of internal stresses in cylindrical objects, such as axles, shafts and tubes made of material with varying non-uniform homogeneous mechanical properties. The method consists in that a beam of ultrasonic waves is thrown onto the surface of a cylindrical object being tested, said beam being refracted at an angle of 90 degrees. Next the times of passage for every type of waves are measured. On the basis of the calculated differences of the times of passage with a standard the absolute values of components of stresses are calculated. The method is applicable for non-destructive testing of properties and structure of materials and products.

Abstract: The present invention utilizes measurements of the characteristic standing pressure wave frequencies in normally liquid-filled pipes to detect the presence of gas bubbles or gas pockets within the pipes. Because gases, for example air, are more compressible than liquids, gas in a pipe causes the natural frequencies of standing waves to be shifted from their values with no gas. The characteristic standing wave frequencies are determined from a Fourier transform of pressure fluctuations within the pipe. The pressure fluctuations, measured using a hydrophone or other pressure transducer, are due to either background flow noise (passive technique) or a deliberately induced pressure transient (active technique). The technique is sufficiently sensitive to detect relatively small gas bubbles as well as complete gas blockage. The apparatus required depends somewhat on whether the particular application requires use of the active or passive technique.

Abstract: An arrangement in which at least one ultrasonic sensor is coupled to an article to be tested by a liquid coupling medium in an automatic ultrasonic testing of strips, sheets, and pipes that follow each other as individual pieces. The sensor is positioned along a testing path at a constant distance away from the article by a holder. The sensor has a sound emisson surface, and at least one separate free jet of coupling medium is positioned at a side of the sensor in a plane crossing the testing path. The free jet intercepts a central axis of the sound emission surface, and a layer of coupling medium is formed between the sound emission surface and the surface of the article. Testing of the article includes interior regions covered by all surfaces of the article, as well as the end regions and edges of the article.

Abstract: The surface of a cement intimate mixture filled portion in a building is tapped by a hammer, and a tapping sound thus generated is received by a micropone and converted to an electrical signal. The electrical signal representing the attenuation characteristic, which is different depending on the presence or absence of a defective unfilled portion in the cement filled portion, is sampled to obtain a maximum peak value and/or an integrated value. The maximum peak value and/or the integrated value is compared with a reference value to decide the presence or absence of a defect in the cement filled portion.

Abstract: An apparatus is provided for determining the natural frequencies of a longitudinally oscillating band excited by a transmitting oscillator, and whose oscillations are received by a receiving oscillator and evaluated. At least one of the exciting oscillator and the receiving oscillator is a sandwich oscillator having metal end masses. The oscillations are transmitted longitudinally along the pre-tensioned length of the band disposed between the transmitting oscillator and the receiving oscillator. An attachment device for attaching the band to the respective oscillators includes a roller which is spring-biased to rest in a groove formed in one face of each of the respective oscillators.

Abstract: A procedure for analyzing air content of a liquid, e.g. pulp slurry, wherein the ratio I.sub.att /I.sub.sc between ultrasound attenuation and scattered ultrasound attenuation and/or the logarithm log (I.sub.att /I.sub.sc) is determined. The respective measuring apparatus comprises an ultrasound transmitter (1) and an ultrasound receiver (2) and a scattered ultrasound receiver (3), the latter being disposed to measure members (4) for determining the ratio I.sub.att /I.sub.sc and/or the logarithm log (I.sub.att /I.sub.sc).

Abstract: A colloid analyzer is provided employing a relatively low frequency, low power, continuous "acoustic" wave signal propagated in the direction of spaced electrodes mounted adjacent to the side wall of a chamber or vessel containing a colloid sample. The chamber further comprises a series of probes for respectively sensing the pH, temperature, and conductivity of the sample(s) being analyzed. A piezoelectric transmitter generates the acoustic drive signal. The spaced electrodes in conjunction with an electronic signal processing circuit serves as a receiver and generates an output signal relating to the magnitude and polarity of the zeta potential of the particles being "acoustically" excited by the drive signal. A computer responsive to the signal processing circuit's output signals and/or the vessel probes' output signals alternately develop a graphical output relating to zeta potential, and/or one relating to the surface charge density of the analyzed colloid for given levels of titration.

Abstract: The multicomponent transducer of the present invention comprises a housing having interior surfaces forming an enclosed cavity and a single inertial mass immersed in a magnetic fluid contained therein. The inertial mass is levitated in the magnetic fluid by means of ferrohydrodynamic forces. The housing cavity and the inertial mass are generally spherical in shape such that the inertial mass is substantially unconstrained with respect to the directions of motion to which it is responsive. The multicomponent transducer also includes motion sensing means for sensing selected components of motion of the inertial mass and for generating signals representative of the magnitude and periodicity of the relative motion of the inertial mass with respect to the housing along one or more separate axes. The multicomponent transducer of the present invention has amplitude and phase responses similar to those of conventional transducers.