Abstract: In a pulse-echo ultrasonic circuit an ultrasonic search signal is periodically transmitted into a workpiece. The ensuing pair of echo signals (entrant and rear surface reflection respectively) are fed to a timing circuit for providing a timing signal responsive to the time interval between the two echo signals. A fixed pulse width pulse generator is triggered responsive to the search signal. The output from the fixed pulse width generator and the timing signal from the timing circuit are selectively fed to a converter circuit for providing an output signal indicative of workpiece thickness or workpiece acoustic velocity. The converter circuit includes adjustable parameters comprising current magnitude and resistance to provide suitable calibration. Similar calibration is achieved also by varying the repetition rate of the search signal.

Abstract: Acoustic discontinuity responsive echo signals are compressed using special evaluating means for increasing the resolution of pulse-echo test apparatus. The acoustic discontinuity responsive echo signal undergoes mathematical convolution with a predetermined signal which latter signal is selected for providing that the mathematical product of the Laplace transform of the echo signal and the predetermined signal is unity. The mathematical convolution is performed by a computer, a correlator or an arrangement of delay lines.

Abstract: An eddy current coil test assembly comprises a printed circuit board having respective conductors which form the excitation coil winding, the sensing coil winding, the input transformer winding, the output transformer winding and the connections between these respective elements. Pot core type transformers are mounted in close proximity to said windings. The printed transformer windings constitute respectively the secondary winding of the input transformer and the primary winding of the output transformer.

Abstract: The invention refers to an ultrasonic measuring means exhibiting improved stability and calibration adaptability. Ultrasonic energy signals are transmitted into a workpiece and echo responsive signals are received therefrom. A timing signal having a pulse width commensurate with the workpiece thickness is generated. The pulse width is measured by a time interval averaging circuit in combination with a programmable counting means for adjusting the quantity of time interval average measurements required for determining the thickness of the workpiece. The programmable means is adjusted to a value commensurate with the acoustic velocity of the workpiece for causing the output of the apparatus to display the dimension of the workpiece measured.

Abstract: A storage battery comprising a thermoplastic cover having a hollow metallic terminal therein and a thermoplastic case having an upstanding metallic core member passing through the terminal is assembled using vibratory energy. The cover and the case undergo relative reciprocating translating motion while under the influence of a static force applied in a direction perpendicular to the plane of the mating surfaces between the cover and case. The terminal and core are dimensioned for providing a peripheral clearance around the core in the direction of the reciprocating motion at least equal to the peak-to-peak displacement of the vibratory motion. The gap existing between the core and the terminal when the battery is assembled is sealed.

Abstract: The invention refers to a method of forming over the edge of a plastic jacket against a workpiece using vibratory energy. Specifically, the workpiece and jacket are disposed on a resiliently mounted anvil. As the jacket forms over and shortens its axial length, the anvil is displaced to provide a decreasing engagement force between the jacket and the horn of the vibratory apparatus. As a result, the jacket is free of scars or distortions in the region of forming.

Abstract: This invention refers to an ultrasonic pulse-echo nondestructive test method and apparatus for causing the axis of an ultrasonic energy search beam path transmitted from an ultrasonic transducer probe to a workpiece to be maintained normal to an irregularly contoured workpiece entrant surface. Electrical circuit means measure and compare the echo signals reflected from the workpiece and cause the search probe to be positioned to maximize the amplitude of the received signals.

Abstract: This invention discloses the plating of a metallic workpiece, particularly aluminum with a layer of tin. The plating is accomplished in the presence of sonic or ultrasonic vibrations at a temperature determined by the phase diagram for a binary alloy to provide for the presence of an alloy interface encompassing both metals. This contrasts with the heretofore achieved adhesive bond.

Abstract: Two telescopingly engaging tubular thermoplastic workpieces are welded together by ultrasonic vibratory energy applied radially. The workpieces are disposed on a mandrel for preventing distorting or collapsing of the opening in the inner workpiece. A tapered hole in the ultrasonic tool in combination with an axial force upon the workpiece provides a radially compressive force upon the outer workpiece to cause intimate contact between the softened workpiece surfaces during welding.

Abstract: This invention refers to a novel arrangement for mounting a vibratory assembly concentrically within a cylindrical housing for use in a vibratory seam welding apparatus. A pair of metal diaphragms support the vibratory assembly at antinodal regions of motion along the longitudinal axis. These diaphragms are constructed for supporting the assembly within the housing and for providing acoustic energy isolation between the vibratory assembly and the housing while being yieldable in the direction of the vibratory motion along the axis of the assembly.

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: This invention refers to an overload protection circuit for an oscillatory circuit driving an electro-acoustic converter and more specifically concerns a circuit for automatically inhibiting the oscillatory circuit in the presence of an overload. The overload protection circuit monitors the collector-emitter voltage signal and the base-emitter voltage signal for providing an overlap signal responsive to the interval when both mentioned voltage signals are in their high condition. Such a condition is indicative of the power dissipated in a switching transistor of the oscillatory circuit. The overlap signal is integrated and the integrated signal is compared to a predetermined voltage level. When the integrated signal exceeds the predetermined voltage level, the oscillatory circuit is inhibited.

Abstract: The present invention refers to a method of ultrasonic testing a workpiece by the pulse-echo technique and an apparatus therefor. An initial portion of a workpiece to be tested is conveyed past an array of electroacoustic transducer probes. The transit time through the workpiece of the transmitted ultrasonic signals from each probe comprising the array is measured. The maximum measured transit time is stored. Subsequently as a slightly shifted second portion of the workpiece is conveyed past this array of transducers, the transit time through the workpiece of ultrasonic signals transmitted by each probe of the array is again measured. The stored value is updated responsive to the latter obtained values. The final updated value is conducted to a flaw detector circuit for terminating a defect gate used in conjunction with testing the workpiece for defects by the pulse-echo test method.

Abstract: An ultrasonic welding and cutting apparatus designed for the manufacture of articles made of two superposed sheet materials includes an anvil means which exhibits a raised pattern of welding and cutting surfaces, and bearing surface means for limiting the motion of an ultrasonically vibrating horn toward the anvil means and for distributing also the impact forces manifest upon the anvil means. The horn is provided with means for reducing the motional excursion of the frontal surface portion which impacts upon the bearing surface means.