Abstract: The disclosure is directed to an ultrasonic transducer device that includes a plurality of layers of piezoelectric material. A plurality of conductive electrodes are disposed on the layers of piezoelectric material such that each layer of piezoelectric material has electrodes on opposing surfaces thereof. A series string of electronic delay means is provided, and has successive stages that are respectively coupled between pairs of the electrodes. An input/output terminal is coupled to an end of the series string of electronic delay means. The time delay of each electronic delay means is selected as a function of the ultrasonic wave propagation time through the piezoelectric material across which the electronic delay means is coupled. Preferably, the time delay of each electronic delay means is substantially equal to the ultrasonic wave propagation time through the piezoelectric material across which the electronic delay means is coupled.

Abstract: An ultrasonic atomizing device includes an ultrasonic oscillator system and a housing. The oscillator system comprises a conic-frustum shaped coupler having a projection at the central portion of its large cross-sectional portion, a circular piezoelectric plate provided with electrode plates and having a center hole through which being penetrated the projection, and a resonance plate to be stimulated into vibration. On the other hand, the housing includes a cylindrical wall, a circular cover fixed at one end of the cylindrical wall and a ring shaped cover fixed at the other end of the cylindrical wall. A circular hole of the ring shaped cover accepts and flexibly supports the coupler through a ring shaped rubber packing. The surface of the oscillator is sealed with the housing by fixing the circular cover to the projection by means of screws, in order to prevent invasion or adhesion of liquid to the surface of the oscillator.

Abstract: An acoustic fuel injector-atomizer comprising a horn (74) actuated by piezoelectric crystals (28a, 28b) to form a resonant structure (18) excited by an oscillator signal. The oscillator (16) which generates the excitation signal is self-tuned to the resonant frequency of the structure (18) by means of a first transformer coupling (66, 56) which provides a feedback path between the structure (18) and the oscillator transistor (24) and a second transformer coupling (68, 56) which provides a compensation signal representing static capacitance of the crystals (28a, 28b). The compensation signal is subtracted from the feedback signal of the structure (18) so as to eliminate the static capacitance component as an error source in the self-tuning function.

Abstract: An ultrasonic transducer and its method of fabrication wherein bonding between an impedance matching layer on one side of a piezoelectric layer and a support layer on the other side of the piezoelectric material is made by providing onto each material a smooth, thin gold film on the smooth surfaces of the layers which are to be in contact with one another in the assembled transducer. The layers are bonded to each other by the gold films under moderate temperature and pressure to form the transducer. Sawing of the impedance matching and piezoelectric layers into a plurality of parallel transducers attached to the support layer forms an array.

Abstract: This invention relates to resonators as used in sonic or ultrasonic apparatus. Particularly with bar type resonators there is manifest a reduction of vibrational amplitude at the output surface from the central area toward the lateral edges. In the present arrangement the input surface is provided with pads to increase the mass ratio between the input and output sections for effecting substantially uniform motional amplitude along the entire output surface.

Abstract: An ultrasonic liquid atomizer is disclosed in which the liquid feed to the atomizing surface extends axially through the atomizer. This arrangement enables improved and simplified coupling of the liquid supply tube to the atomizer. In a disclosed embodiment, rear and front horn sections sandwich a driver, and an atomizing section is coupled to the front horn section. A passage axially extends through the rear section, the driver, the front section and the atomizing section to an atomizing surface. The driver includes piezoelectric elements of annular configuration. A tubular member or a liquid supply tube itself is received in the passage. In a preferred embodiment, the tubular member of the liquid supply tube includes a decoupling sleeve section and a stepped portion adapted to engage a stepped portion in the rear section upon coupling the tubular member or liquid supply tube to the atomizer to draw the front and rear sections together.

Abstract: A method of treating material in a vessel includes the steps of vibrating the vessel to produce oscillatory displacement of the vessel wall; and transmitting such displacement to material in the vessel. The vessel may comprise a tube having a tuned cavity in which material is treated; or the vessel may contain relatively movable solid bodies to which the vibration is transmitted to grind or emulsify material flowing between the bodies; or, the vessel may contain a pumping member to which vibration is transmitted to cause material pumping displacement of that member.

Abstract: A method for closing an open end of a thermoplastic tube by applying ultrasonic energy to the end in a direction normal to the longitudinal axis of the tube. A horn adapted to undergo ultrasonic vibrations is provided and includes an open cavity disposed substantially at an antinodal region of longitudinal motion of the horn and oriented normal to the direction of longitudinal motion of the horn. The horn is rendered resonant along its longitudinal axis while the open end concomitantly is urged into the cavity in a direction normal to the direction of longitudinal motion of the horn thereby forming the end to the shape of the cavity.

Abstract: A piezoelectric fluid atomizer comprises an oscillating plate which is made to resonate by means of an electric alternating voltage. The element causing the oscillations is a piezoceramic converter which is connected to the oscillating plate via a cylindrical extension part. The cylindrical extension with the oscillating plate is constructed as an axial extension of the front side of a bolt which comprises a widened portion in the form of an abutment plate adjacent the cylindrical extension. The bolt supports converter elements which are shaped as rings and which are pressed across the bolt against the abutment plate by means of a pressure plate. A shield which extends across the converter elements is secured on the bolt at some distance behind the pressure plate. In operation an oscillation node is present for the freely suspended part supporting the piezoelectric converter elements, at the area of the abutment plate.

Abstract: An ultrasonic half-wavelength resonator characterized by an input surface and an output surface both being disposed at antinodal regions of the longitudinal vibratory energy travelling through the resonator and a medially disposed nodal region is provided with a plurality of slots disposed in the resonator extending from a region near the input surface to a region near the output surface and passing through the nodal region. The slots being angled relative to the longitudinal axis of the resonator from the input surface to the output surface to provide substantially uniform motion along the output surface of the resonator.

Abstract: A transducer assembly includes a first half wavelength double-dummy section having a pair of quarter wavelength ultrasonic horns and a driving element sandwiched therebetween. A second half wavelength stepped amplifying section extends from one end of the first section and has a theoretical resonant frequency equal to the actual resonant frequency of the first section. When used as a liquid atomizer, the small diameter portion of the stepped amplifying section has a flanged tip to provide an atomizing surface of increased area. To maintain efficiency, the length of the small diameter portion of the second section with a flange should be less than its length without a flange. A decoupling sleeve within an axial liquid passageway eliminates premature atomization of the liquid before reaching the atomizing surface. In a fuel burner incorporating the atomizer, ignition electrode life is increased by locating the electrodes outside the normal flame envelope.

Abstract: A drop generator for an ink jet printer comprises a mechanical vibration amplifier which is adapted, when set in vibration at one end, to cause at least one ink jet emitted from its other end to break up into drops. An electromechanical converter device is fitted at said one end to impart a vibratory movement to the amplifier when it is excited electrically. A compensating block is attached to the electromechanical converter device so as to set up in the latter a nodal vibration zone. A support member holds the generator in position in the printer and the part of the support member which is in contact with the generator is situated in the nodal zone.

Abstract: A control system for a Tonpilz transducer which is positioned between the transducer and the transducer drive amplifier. The control system determines the head velocity of the transducer from the input current and voltage and utilizes this determination in a feedback arrangement to maintain proper transducer excitation.

Abstract: The invention concerns an improved apparatus for removing interior material coatings in various containers such as sanitary bowls. The apparatus may be partially or completely immersed or introduced into liquid in a container to be cleaned and due to an improved arrangement of high frequency vibrator elements in the interior of an immersed apparatus housing, a particularly efficient and uniform power emission may be achieved from the oscillating housing walls, said power providing cavitations at the container walls to be cleaned whereby coatings may be loosened in an effective manner without damaging the container walls.

Abstract: The transducer is formed of at least two metallic blocks (3) with at least one layer 3 of piezo-electric material sandwiched between these metallic blocks, the faces of the layer or layers being metal sprayed to conduct the voltage. One metallic block has at least one projecting element reaching to the opposite metallic block and being connected with the opposite block by means of a binder. Stresses are generated between the layers of piezo-electric material and the metallic blocks originate in the piezo-ceramic material. The faces of contact between the metallic blocks can be either slanted or perpendicular relative to the layers of piezo-electric material. The projecting elements can be made either as dowels or as collars. Oscillations in the transducer are excited by a voltage applied to the transducer terminals.

Abstract: The vibration motor of the invention comprises a concentrator of torsional vibrations including at least two stages. The first one of the stages takes up vibrations from a piezoelectric cell while the second stage contacts a rotor. The concentrator is provided with means for transforming piezoelectric cell vibrations into torsional ones, said means being fashioned as rods provided on the side surface of the first stage. The rods are located in a plane normal to the concentrator axis and inclined each at an acute angle to a tangent at the point where the rod is attached to the line of intersection of the side surface of the first stage with said plane. The rods serve as resonators of longitudinal vibrations propagating therein.

Abstract: An electronically tunable resonant accelerometer is shown wherein the frequency of a resonant peak may be adjusted over a range of frequencies. A piezoelectric element of the accelerometer is used with a seismic mass to generate an output voltage in response to reciprocating motion of the accelerometer. In a compression mode, a feedback loop applies a feedback voltage to a second piezoelectric element mechanically coupled to the first mentioned piezoelectric element. In a cantilever mode, a feedback loop applies a feedback voltage to another location along the first mentioned piezoelectric element which is formed from two bonded piezoelectric elements.

Abstract: An ultrasonic transducer device is disclosed, comprising an elongated front end mass, an elongated tail mass, a pair of piezoelectric elements disposed between said front end mass and said tail mass, an electrode disposed between said piezoelectric elements, means for clamping said front end mass and said tail mass together with said piezoelectric elements and said electrode clamped therebetween, and a mounting member having an opening therein slidably receiving said piezoelectric elements and portions of said front end mass and said tail mass, said opening having a sufficiently loose fit with said piezoelectric elements and said masses to obviate any substantial damping of ultrasonic vibrations. Preferably, said electrode comprises a plate projecting outwardly beyond said piezoelectric elements, said mounting member having an internal peripheral slot within said opening and slidably receiving said electrode plate to restrain said piezoelectric elements and said masses against longitudinal movement.

Abstract: An ultrasonic transducer comprising a first cylindrical member which includes a mechanical vibration amplifying part formed in symmetry around the axis thereof and having a gradually increased cross-sectional area toward a base portion thereof, the base portion having a flat surface perpendicular to the axis thereof, and an annular rigid part formed with the mechanical vibration amplifying part coaxially therewith, the annular rigid part being extended from the outer wall of the base portion axially and radially outwardly to have sufficient rigidity and weight, and the annular rigid part being provided, in the proximity of the outer wall of the base portion, with an annular groove or gap having a predetermined axial depth in order to reduce the diameter of the flat surface.

Abstract: An ultrasonic, surgical and dental probe comprises a piezoelectric crystal transducer assembly positioned in compression between a pair of body members in a housing. Each body member along with the transducer assembly is mounted on a hollow connecting rod. An interchangeable operative tip, disposed within the hollow connecting rod, is releasably secured to the housing. In a first embodiment, one end of the tip contains a keyhole slot that snap fits to a transverse pin in the housing. In another embodiment, the body of the tip contains a set of threads which engages a corresponding set of threads formed on the inner wall of the connecting rod. Also disclosed is a unique dental descaling tip used in conjunction with the ultrasonic probe. The working end of the tip which contacts the surface of the teeth contains a first orifice. The orifice discharges fluid for irrigation as the working end of the tip cuts into accretions formed on the teeth during ultrasonic vibration.

Abstract: The scaler includes a transducer and an energizing circuit. The transducer includes a tubular piezoelectric transducer element which is maintained in compressive stress when energized by an axial tension bolt adapted to mount a vibratory work tool. The energizing circuit drives the transducer element at its resonant frequency and maintains resonant frequency within an optimum band width, despite changes in capacitive reactance of the transducer element produced by torque applied thereto as the work tool is pressed against an object. A fluid delivery system delivers fluid to the work tool via the tension bolt to effect scaling.

Abstract: A transducer assembly includes a first half wavelength double-dummy section having a pair of quarter wavelength ultrasonic horns and a driving element sandwiched therebetween. A second half wavelength stepped amplifying section extends from one end of the first section and has a theoretical resonant frequency equal to the actual resonant frequency of the first section. When used as a liquid atomizer, the small diameter portion of the stepped amplifying section has a flanged tip to provide an atomizing surface of increased area. To maintain efficiency, the length of the small diameter portion of the second section with a flange should be less than its length without a flange. A decoupling sleeve within an axial liquid passageway eliminates premature atomization of the liquid before reaching the atomizing surface. In a fuel burner incorporating the atomizer, ignition electrode life is increased by locating the electrodes outside the normal flame envelope.

Abstract: A flowmeter transducer assembly specially designed for high temperature operation includes only dry-coupled elements. A subassembly preassembled before installation on the pipe section consists of a piezoelectric element held between front and backing electrodes. The backing electrode is backed by a contact electrode while leaving a gap therebetween to prevent reflection of acoustic energy back to the rear of the transducer. The subassembly is introduced into a housing clamped directly on a flow section of a pipe, where the pipe wall is an acoustic wave transmitting or receiving window. In a different embodiment the pipe may serve as the front electrode in dry coupling.

Abstract: A supersonic transducer including means for detecting its vibrating speed and for changing the frequency of the energizing current in response thereto. This invention utilizes the property that when an electrostrictive vibrator is vibrated resonantly, its dynamic admittance varies depending upon the difference in its stress distribution. The electrostrictive vibrator is divided into portions of large and small stresses to cancel the applied brake currents. Simultaneously, a signal is derived that is proportional to the difference of the dynamic currents so as to provide an effective energization by detecting the resonant frequency of the vibrator in order to automatically adjust the applied frequency of the supersonic transducer.