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.

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.

A downhole acoustic emitter including a support housing with a cavity and ports, in which housing are disposed a rod-type magnetostrictive transducer with an electrical coil on the rods, and an acoustic waveguide in the form of a cylinder which transitions into a tapering cone. The cylindrical portion of the acoustic waveguide is disposed inside the support housing, and the conical portion is disposed outside the housing. The upper end surface of the acoustic waveguide is coaxially joined to the lower emitting surface of the magnetostrictive transducer by soldering, and the acoustic waveguide is joined at its middle portion, which coincides with the zero vibration point of the waveguide, to the support housing by a threaded joint. The downhole acoustic emitter is provided with an emitting element, the upper end of which is coaxially joined to the lower end of the acoustic waveguide by a threaded joint. The magnetostrictive transducer has a length of 200-280 mm and is made of Permendur, and the ports are arranged around the perimeter of the support housing in two rows, the first of which is level with the top turns of the electrical coil of the magnetostrictive transducer, and the second row is level with the bottom turns of the coil. The emitting element is in the form of a cylinder or a prism with a square cross-section.

A downhole acoustic transmitter has a piezoelectric transducer, an enclosure in which the piezoelectric transducer is housed, a transducer preload means which applies a selected compressive force against the transducer such that a mechanical preload is applied to the 5 transducer, and an acoustic tuning element which has a first end coupled to the transducer preload means or the transducer, and an open second end. The acoustic tuning element is not coupled to anything but the transducer preload means or transducer, so the transducer preload means effectively has a second open end and thus can maintain the same preload compressive force on the transducer even when the transmitter is subjected to tension and 10 compressive forces during operation.

Methods of mitigating current overload of an ultrasonic system having an ultrasonic stack under load at startup are provided. The methods include beginning an ultrasonic cycle in the ultrasonic system having the ultrasonic stack that runs a closed loop phase control through the weld cycle by ramping up the power of the ultrasonic stack under load. During ramping up of the power of the ultrasonic stack under load, a controller lowers the phase to a negative phase. After ramping up the power of the ultrasonic stack under load is complete, the controller raises the phase to 0 degrees and the ultrasonic stack is operating at steady state and with the phase at 0 degrees.

A device and a method for generating percussive pulses or vibrations for a construction machine, in which a piston is reversibly reciprocated in a working space in a housing between a first reversal point and a second reversal point, wherein, for the purpose of generating the percussive pulses or vibrations, the piston is set into a reversible movement by means of a pressure fluid and the said pressure fluid is led into and out of the working space in the region of the first reversal point and the second reversal point. The position of the piston is detected by way of a measuring means, in that depending on the detected position of the piston a control unit controls at least one controllable valve, through which pressure fluid is led into and/or out of the working space, wherein by the control unit the movement of the piston is controlled.

A novel mode of ultrasonic oscillation is generated in a Langevin ultrasonic transducer comprising a metal block, a metal block provided with a supporting means protruding in a ring shape on its side surface, and polarized piezoelectric elements fixed between these metal blocks, by connecting the ultrasonic transducer to a base via the supporting means, whereby supporting the ultrasonic transducer on the base in a restrained state, and applying to the piezoelectric elements a voltage having such frequency that the ultrasonic transducer generates an ultrasonic oscillation with back-and-forth motion in a direction perpendicular to plane surfaces of the piezoelectric elements which has no oscillation node within the ultrasonic transducer; this novel ultrasonic oscillation mode is utilized for performing ultrasonic machining methods as well as for ultrasonic transmission method.

The present invention relates to a method and a device for controlling an ultrasound tool unit for machining a workpiece on a machine tool. For this, a plurality of parameter sets are stored on a storage device of a control device of the machine tool. When controlling an ultrasound transducer of the ultrasound tool unit received on a work spindle of the machine tool on the basis of a sensor signal input into a controller by means of a generator operated by the controller, on the basis of a first parameter set, which is associated with the ultrasound tool unit and sets the operation of the controller, an operating setting of the controller is switched by changing the first parameter set setting the operation of the controller on the basis of a second parameter set, which is associated with the ultrasound tool unit, of the plurality of parameter sets stored on the storage device.

A system and downhole tool comprising an ultrasonic transducer with a piezoelectric material embedded in a backing and a method of determining a parameter using the ultrasonic transducer. A self-noise of the transducer can be reduced by the piezoelectric material being at least partially embedded in the backing. The ultrasonic transducer can include an encapsulating material that encapsulates the backing.

A pneumatic vibration device with a rotatable piston shaft comprises a piston body and a gas diverter. The piston body comprises a piston shaft, an input shaft and a piston cylinder body. The piston shaft comprises a hollow spindle with two ends connected to a first piston and a second piston through connection bearings respectively. The first piston and the second piston are connected through an inner sleeve. The spindle is connected to a rotary connection member. The input shaft stretches into the inner sleeve and is matched and connected with the rotary connection member. The gas diverter comprises a first gas diversion port and a second diversion port. The pneumatic vibration device is compact in structure and high in adaptability, and can realize rotation and vibration of drilling tools.