Abstract: In a wire bonding head, a transducer block depends from a carriage block via a special link mechanism including a main link member pivotally attached to the carriage block at its one end and to the transducer block at its other end so that the bonding tool tip may move along a vertical and linear path without any lateral displacement as the transducer block moves toward and away from the carriage block. Because the carriage block essentially undergoes a pivotal motion around the pivot on the carriage block, the effective inertia of the transducer block is kept small as compared to the case where a translational motion is caused to the transducer block. The structure according to the present invention is relatively simple and low in cost, and can be made free from plays particularly when the pivots consist of spring pivots using flexures.

Abstract: First and second ultrasonic sensors 1A and 2A are arranged facing each other, and these ultrasonic sensors 1A and 2A are provided with first and second reflectors 1 and 2 on their surface, respectively, and thereby, a propagation time t.sub.t of ultrasonic wave in a distance L within a medium subject to measurement is determined from the following equation t.sub.t =(t.sub.4 -t.sub.3 +t.sub.2 -t.sub.1)/2.

Abstract: A portable ultrasonic underwater sensor 15 has a piezoelectric element 21 disposed in a case 22 constructed as a cylinder 24 and having a truncated cone 25 both being integrally and axisymmetrically formed so as to constitute a vibrator 22A. A piezoelectric element 21 and the vibrator 22A are bonded together with a center of the piezoelectric element 21 matches the center of a reverse face of the truncated cone 25 of vibrator 22A, whereby the vibrator 22A is entirely resonant in a vibration mode in which flexional vibration at the center of the truncated cone 25 is a maximum amplitude, and wherein means for holding the vibrator 22A is located along a vibration nodal line on an external side face of the vibrator 22A.

Abstract: A method and apparatus for ultrasonic wave measurement wherein the time interval between like order echoes selected with respect to adjacent transmitted waves is controlled to be equal to an integral multiple of a period (t.sub.3) of a continuous oscillation wave. In addition, the time interval between like order echoes adjacent to each other that are selected with respect to the same transmitted wave is controlled to be equal to the period (t.sub.3) of the continuous oscillation wave. The period (t.sub.3) of the continuous oscillation wave that is obtainable under the above controlled state, is measured, and the result of the measurement is used as ultrasonic wave propagation time for obtaining the absolute sound velocity.

Abstract: In an ultrasonic oscillator which comprises an ultrasonic vibrator for driving an ultrasonic vibrator horn of an ultrasonic atomizer, a balanced circuit in which the ultrasonic vibrator is connected so that a balanced condition is established with respect to the damping capacity of the ultrasonic vibrator, and amplifier means for sending a signal to the balanced circuit and which includes a feedback circuit for positively feeding back the signal output from the balanced circuit, the feedback circuit is connected to means for adjusting the feedback quantity so that, when the ultrasonic oscillator starts the oscillation, the signal feedback quantity output from the balanced circuit is adjusted to make the gain of the amplifier means much greater than 1, and when the oscillator is in the steadily oscillating condition, the signal feedback quantity output from the balanced circuit is adjusted to broaden the allowable frequency band width of the ultrasonic vibrator.