Abstract: Apparatus for creating vibratory forces in a specimen in which the specimen is positioned within a carrier which is rotated about a remote axis, preferably vertical, to generate centrifugal forces directed radially outward from the remote axis. The carrier is also rotated about an axis perpendicular to the direction of the radial centrifugal force so that the force on any particle is cyclically reversed at a frequency determined by the frequency of the rotation about the perpendicular axis. The rate of rotation about the remote axis may be varied to vary the amplitude of the centrifugal force and the rate of rotation about the perpendicular axis may be varied to vary the frequency of the vibratory force generated by this combination. The specification discloses an apparatus in which a solid specimen may be mounted for the generation of cyclically-varying vibration forces and also an apparatus for receiving a liquid which may be subjected to cyclically-varying vibrational forces.

Abstract: An apparatus and method for determining a velocity of propagation and the thickness of different substances such as pipe walls utilizes a transducer connected to an A-scan. This material is placed in a holder between the transducer and a reflecting surface, the holder containing a fluid having a known velocity of propagation. The transducer converts high voltage electrical pulses produced by a generator into ultrasonic vibrations and also converts echo signals received from the reflecting surface and the material back into electrical pulses. A display device connected to the transducer displays these pulses and their exact position on the display device is used to determine the velocity of propagation and the thickness of the material.

Abstract: An alignment control is described whereby the orientation of a turntable can be adjusted from outside of a tank in which an ultrasonic test system operates. The alignment control employs a diaphragm which is mounted over an opening in the bottom of the tank and is formed of a material capable of being flexed while supporting liquid inside the tank. The diaphragm is firmly gripped by a pair of clamp plates respectively located inside and outside of the tank. The clamp plates effectively support the turntable through a drive shaft and bearing with a pivot control connected between the outer clamp plate and an external segment of the tank. External alignment of the turntable as well as external rotational drive are advantageously provided.

Abstract: An automatic weld flaw detector comprises a comparator for comparing the height of an echo from a detected flaw upon movement of a probe over each unit distance with a maximum echo height already known, a counting circuit adapted to work in response to the comparing action of the comparator so as to determine the distance the probe has covered, a device adapted to be actuated by the output from the comparator thereby to memorize separately the maximum value of echo height and the output at that moment from the counting circuit, and a recorder connected to the memorizing device.

Abstract: A device for indicating the interval for the flow of a predetermined volume of fluid. The fluid flow measurement device includes a housing having a cavity therein for being interposed along a fluid line. A flexible diaphragm having a convolution therein is included within the cavity for dividing the cavity into a first and second chamber. The flexible diaphragm prevents the flow of the fluid between the first and second chambers. A fluid port connects the second chamber to the fluid flow line. A fluid outlet connects the first chamber to the fluid flow line. The apparatus also includes a bypass for diverting the fluid flow from the fluid port of the second chamber through a fluid inlet into the second chamber, whereby the fluid flowing into the second chamber will displace the flexible diaphragm into the first chamber thereby expelling the predetermined volume of fluid from the first chamber.

Abstract: A drum rotatable about an axis through its center of gravity carries troughs located in a circle concentric to said axis and which are charged at a certain level with flowing material to be measured as to quantity, whereby the drum is influenced by a driving moment from the weight of the charged material. After a certain rotation of the drum, the troughs discharge the charged material at a lower level than said charging level. Means are provided for counteracting rotation of the drum by said driving moment, said means including interconnected scoops arranged in a circle concentric to an axis through the common center of gravity of the scoops, said last axis forming an angle with a vertical line. The drum rotates the scoops around said last-mentioned axis, and the scoops successively elevate a second material from a certain level and discharge it at a higher level.

Abstract: A fluid flow meter of the variable area flow passage type is provided wherein the variation in said flow passage area is effected by the vertical displacement of a control boundary which is supported by a substantially horizontal annular diaphragm element. Said control boundary is shaped and sized so that the overall displacement required for the flow rate range desired is within the stroke capacity delivered by the total, up and down, free flexing action of said diaphragm element, thereby achieving substantially constant differential pressure operation at a very reasonable value which is due almost entirely to gravity. The resulting unit is very compact and stable and is characterized by very smooth linear response between vertical displacement and fluid flow rate. Said vertical displacement can be measured by various means but is preferably transduced to an equally linear, smooth and steady electrical signal by a direct connection with a specially adapted differential transformer.

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: A plurality of circular cross section elongated vibrometer reeds each having a predetermined frequency response to a vibration in a given plane are secured to a vibration transmission medium in predetermined orientations. The medium is secured in vibrating communication with a machine frame, for example, a helicopter frame, to transmit frame vibrations to the reeds. Each reed is oriented to respond to at least one vibration associated with a known source of vibration in an environment of complex vibrations produced by a plurality of sources in the machine.

Abstract: A device for measuring the flow of a fluid in a pipe by creating aneasily measurable pressure differential which is related to flow comprises a diaphragm transversely contained in the pipe or an associated branch pipe. The diaphragm has a multiplicity of closely spaced fluid flow holes which are so shaped as to increase fluid flow velocity through the diaphragm, and means are provided downstream faces of the diaphragm said means being intended to be connected to a differential pressure indicating or recording instrument from which a fluid flow measurement can be derived.

Abstract: A transducer for measuring the amplitude of vibration of a member vibrating at a constant frequency. An outflow aperture is supplied from a compressed air supply, and opposite to the outflow aperture an obstructing element is arranged which can close the outflow aperture, the outflow aperture and element undergoing relative motion transverse to the direction of air flow. The average quantity of outflowing air is measured.

Abstract: Fluid flow in small bore conduits is measured and controlled utilizing a Doppler flowmeter to measure flow rate. The fluid is then passed through a static chamber in which sound speed in the fluid is measured by a velocimeter. The outputs of the flowmeter and the velocimeter are multiplied to correct the measured flow rate for errors due to its sound speed dependency. The corrected flow rate may be then used to control a pump to provide the desired flow rate.

Abstract: A pressure-difference type mass flowmeter with constant volumetric recirculation effected by a pump, with an annular flow path having four junctions each having a spur path. One pair of the alternate spur paths serve as inlet and outlet of the fluid flow to be measured, while the other pair of the alternate spur paths are connected to the recirculation pump. Four sections of the annular flow path defined by the four junctions are each provided with static fluid pressure sensing point, and a transducer gives a readout of difference in average static pressures of one pair of the alternate sensing points and of the other pair of the alternate sensing points. This readout is linearly proportional to the fluid mass flow rate.

Abstract: A unit for measurement of the velocity of air flowing into or out of an opening such as the heating or air conditioning register or grill. An open end of a collecting section is placed over the opening and the air flows through a measuring section at the opposite end of the chamber. The measuring section includes a pair of hollow manifold tubes each having a smaller diameter, hollow sensing tube mounted coaxially therein. Air flows into a plurality of probes communicating with the interior of one manifold tube, into the associated sensing tube, through a velocity meter, through the other sensing tube into the other manifold tube, and out through a second plurality of probes also positioned at the opposite end of the collecting section. An orifice or constriction in the line leading to the flow meter inlet controls the flow and allows for full scale deflection of the meter within a selected range to permit accurate calibration.

Abstract: An apparatus for providing an ultrasonic sectional view stating the proportion of meat and lard in biological material. The apparatus comprises a transducer unit and an ultrasonic pulse generator providing a periodically scanning window. Said transducer unit comprises at least two multi-crystal units, the longitudinal axes of which may form a variable angle. The joint between the multi-crystal units comprises an angle information unit. By means of said angle information unit and the means for visualizing reflected ultrasonic echoes it is possible to visualize marginal surfaces.

Abstract: A transducer positioner for testing conduits from the interior comprising a standard pulse-echo ultrasonic instrument converted to a detection package comprisingA. a head which positions at least two transducers simultaneouslyB. a connecting tube to provide a water column for coupling each transducer to the conduit to be testedC. connecting cables from each transducer to the ultrasonic source instrument, andD. a terminal box containing connectors and a calibration transducer.

Abstract: A scanning acoustic microscope wherein a high frequency acoustic plane wave is focused by an acoustic lens to scan an object at the focal plane and is then recollimated by a second acoustic lens, detected with a piezoelectric detector, and the detected acoustic signal applied to an oscilloscope to provide a visual display.

Abstract: An electroacoustical flow meter for measuring flow rates in open and closed channels includes two sets of transducers, one set being positioned upstream relative to the other set. Flow rates are determined by computing the difference between upstream and downstream transit times of acoustical signals transmitted along various paths through the channel. A receiver in the flow meter monitors the acoustical signals received after each transmission. When an acoustical signal is received which has been attenuated due to disturbances such as obstructions along the signal path or interfering reflected signals, the receiver transmits a flag signal. This flag signal is utilized to minimize flow rate reading errors which normally result from such disturbances.

Abstract: Apparatus for use in inspecting ferromagnetic wall members. The apparatus comprises a telescopically extendable pole member having a carriage attached to the extendable end of the telescope. The carriage comprises a mounting frame attached to one of its ends to the extendable end of the telescope. A shaft extends through the mid portion of the mounting frame generally perpendicular to the telescope. Wheels consisting at least in part of permanent magnetic material are rotatably mounted on each end of the shaft. An ultrasonic transducer is attached to the other end of the mounting frame. An electric current carrying cable is electrically connected to the transducer and a waterline having an open end adjacent the end of the transducer is attached to the mounting frame.

Abstract: Apparatus for a color coded visualization of ultrasonic field patterns resenting differences in acoustical impedance within a solid or liquid body. Colored ultrasonic images are obtained in response to a multifrequency interrogation of a test specimen by a multifrequency energization of an ultrasonic transducer with indications of characteristic color being obtained at the loci of discontinuities or inhomogeneities in the specimen (solid and/or liquid) being examined. Colored images are provided by an electronic superposition of images on a color television monitor subsequent to the images being color encoded in accordance with at least two, but preferably the three primary colors of red, green and blue.