An ultrasonic actuator with increased radiating surface is presented. The increased radiating surface is provided by a plurality of piezoelectric stacks that are each compressed by action of a respective bolt against a common backing structure of the actuator. According to one aspect, each of the stacks includes a plurality of stacked piezoelectric rings with the respective bolt arranged through the central opening of the rings. According to another aspect, one or both of the backing structure and the horn of the actuator include tuning grooves and/or tuning slots to produce amplitude uniformity of displacement through the actuator. According to another aspect, the radiating surface has a symmetrical shape about an axial direction of the actuator with a lateral dimension that is in a range between one quarter and one half of the wavelength of operation of the actuator.

A dual frequency ultrasonic and sonic actuator with constrained impact mass is presented. According to one aspect, displacement of the impact mass is constrained by cavity to which ultrasonic stress from the tip of a horn is applied. According to another aspect, the displacement of the impact mass is constrained by a spring attached to the tip of the horn. According to another aspect, the displacement of the impact mass is constrained by a flexure. The constrained impact mass converts the ultrasonic stress to lower frequency sonic stress that is coupled to a transmitting element for transmission through a surface. According to one aspect, the transmitting element is a longitudinal probe. According to another aspect, the transmitting element is a drill bit used to penetrate though the surface. According to another aspect, the transmitting element is a thumper used to transmit elastic waves though the surface.

An agitator for vibrating a drill string includes an agitator housing, a rotor and an agitation mass. The drill string has a central axis. The rotor is coupled to the agitator housing and being rotatable about an agitator axis. The agitation mass is coupled to the rotor and is rotatable about the agitator axis. During rotation, a center of mass of the agitation mass is spaced apart from the agitator axis to cause deflection of the agitator axis relative to the central axis to produce vibration in the drill string.

A Transducer in a downhole environment with an increased amplitude of the transducer output at lower frequencies. A transducer may include a bender bar, wherein the bender bar may include a first piezoelectric layer disposed on one surface of the bender bar, a second piezoelectric layer disposed on the opposite surface of the bender bar, and a metallic substrate disposed between the first piezoelectric layer and the second piezoelectric layer. The transducer may further include a first fixed end is attached to the bender bar and connects the bender bar to a base, a second fixed end opposite the first fixed end that attaches the bender bar to the base, and a compartment disposed within the base.

An acoustic transducer array and method of making same. A first metal layer is deposited on a first side of a piezoelectric composite to form a common electrode and a second metal layer is provided over the obverse side. Portions of the second metal layer are removed to create a plurality of individual electrodes. A third metal layer may be deposited onto the plurality of individual electrodes, the third metal layer being thicker than the second metal layer. The individual electrodes extend beyond the piezoelectric composite in the elevation direction to create electrode leads. Metal layers may be provided by lithography, a wireframe or a foil sheet.

A well tool can be used in a wellbore that can measure characteristics of an object in the wellbore. The well tool includes an ultrasonic transducer for generating an ultrasonic wave in a medium of the wellbore. The ultrasonic transducer includes a front layer, a rear layer, backing material coupled to the rear layer, and piezoelectric material coupled to the front layer and to the backing material. The rear layer can improve signal-to-noise ratio of the transducer in applications such as imaging and caliper applications.

Spindle for carrying out machining assisted by non-ultrasonic axial oscillations, including a tool-bearing shaft, and an exciting portion, for subjecting the shaft to non-ultrasonic axial oscillations, especially during its rotation. The exciting portion including a first exciting stage, having at least one piezoelectric actuator, and a second exciting stage, having at least one piezoelectric actuator, having a non-zero axial overlap with the first exciting stage, the actuators of the two stages being arranged so that their effects add.

A vibratory compactor is provided. The vibratory compactor may include a compactor plate, a frame coupled to the compactor plate, wherein the frame may include an inner space and a housing. The frame may include a plurality of mounting brackets coupled between a first side member and a second side member of the frame. The vibratory compactor may include a vibration generation device coupled to the compactor plate within the inner space of the frame. The vibratory compactor may include a plurality of isolators, each isolator coupled to one mounting bracket of the plurality of mounting brackets. The housing may be coupled to the plurality of isolators, wherein the housing may include couplers removably coupled to a top surface of the housing. The couplers may be configured for coupling the vibratory compactor to an excavator type vehicle.

An acoustic transmitter for transmitting an acoustic signal through a downhole medium includes a voltage source; a composite load; and switching circuitry that applies voltage from the voltage source across the composite load in response to a drive signal. The composite load includes charge control circuitry, in the form of at least one inductor, connected electrically in series with a piezoelectric transducer that may be electrically modeled as a capacitor.

An efficiency-enhanced resonant system is provided with a backing mass connected to a linear vibrator, a parasitic mass connected to the linear vibrator, a positioning spring, a connecting device, and external biasing springs. The linear vibrator provides vibrating force to the parasitic mass which is connected to the connecting device, grasping a working implement. The use of separate positioning spring and external biasing springs accommodates a tuned system that balances the reduction in backing mass movement, avoids backing mass resonance within the working range of frequencies, and maintains a minimized linear vibrator stroke within the optimal range for one-dimensional implements within desired frequency ranges. The linear vibrator provides vibration that manifests as a frequency range of the natural frequency of the combined assembly of the parasitic mass, positioning spring, external biasing springs, connecting device, and implement, so that the resonant system efficiently performs work with minimized wasted energy.