135 results about "Magnetostrictive transducers" patented technology

A magnetoclastic transducer for sensing a torque in a shaft (150) is formed by circumferentially magnetising a magnetisable, integral portion (156) of the shaft. To assist in the emanation of a flux-dependent torque, the transducer element portion (156) of the shaft may have further circumferentially magnetised portions (154, 158) to each side. These further portions (154, 158) are of opposite polarity magnetisation to that of the transducer element (156). The external magnetic flux emanated by the transducer (156) is a function of torque and is detectable by a magnetic field sensor (160). An alternative means for the same purpose is to provide the transducer element at a portion (172) of the shaft (170) having an integral annular section of raised profile projecting beyond adjoining portions of the shaft. The shaft may be provided with a series of circumferentially magnetised portions of alternating polarity. A number of ways of achieving circumferential magnetisation are described, together with other directions such as axial. A shaft having the whole or an integral portion of it magnetised can also be used to provide a force transducer sensitive to bending moment induced in the shaft by a force to be measured.

The present invention is directed to a high-powered (e.g., >500 W) ultrasonic generator for use especially for delivering high-power ultrasonic energy to a varying load including compressible fluids. The generator includes a variable frequency triangular waveform generator coupled with pulse width modulators. The output from the pulse width modulator is coupled with the gates of an Isolated Gate Bipolar Transistor (IGBT), which amplifies the signal and delivers it to a coil that is used to drive a magnetostrictive transducer. In one embodiment, high voltage of 0-600 VDC is delivered across the collector and emitter of the IGBT after the signal is delivered. The output of the IGBT is a square waveform with a voltage of ±600V. This voltage is sent to a coil wound around the ultrasonic transducer. The voltage creates a magnetic field on the transducer and the magnetorestrictive properties of the transducer cause the transducer to vibrate as a result of the magnetic field. The use of the IGBT as the amplifying device obviates the need for a Silicon Controlled Rectifier (SCR) circuit, which is typically used in low powered ultrasonic transducers, and which would get overheated and fail in such a high-powered and load-varying application.

An ultrasonic waterjet apparatus (10) has a mobile generator module (20) and a high-pressure water hose (40) for delivering high-pressure water from the mobile generator module (20) to a hand-held gun (50) with a trigger and an ultrasonic nozzle (60). An ultrasonic generator in the mobile generator module (20) transmits high-frequency electrical pulses to a piezoelectric or magnetostrictive transducer (62) which vibrates to modulate a high-pressure waterjet flowing through the nozzle (60). The waterjet exiting the ultrasonic nozzle (60) is pulsed into mini slugs of water, each of which imparts a waterhammer pressure on a target surface. The ultrasonic waterjet apparatus (10) may be used to cut and de-burr materials, to clean and de-coat surfaces, and to break rocks. The ultrasonic waterjet apparatus (10) performs these tasks with much greater efficiency than conventional continuous-flow waterjet systems because of the repetitive waterhammer effect A nozzle with multiple exit orifices or a rotating nozzle (76) may be provided in lieu of a nozzle with a single exit orifice to render cleaning and de-coating large surfaces more efficient. A water dump valve (27) and controlling solenoid are located in the mobile generator module (20) rather than the gun (50) to make the gun lighter and more ergonomic.

Apparatus and method for controlling the frequency of the current in the excitation coil of the handpiece of a dental magnetostrictive ultrasonic scaling unit, or similar transducer. A microprocessor continually samples a predetermined function of the current through the excitation coil, and adjusts the frequency for a function maximum, performing coarse and fine frequency adjustments. The function can be proportional to the current, its time-derivative, or combination thereof A voltage-controlled oscillator is employed, controlled by pulse-width modulation from the microprocessor. The base frequency scan is performed each time the handpiece is energized by the practitioner, assuring automatic optimal frequency adjustment at all times and under all conditions. Apparatus according to the invention does not require transformers, sensing coils, or complex power- or impedance-sensing circuitry, and covers a wide range of resonant frequencies for different insert types. A configuration with multiple handpieces is supported.

Devices including a magnetostrictive transducer, an oscillating system and a tool for ultrasonic impact treatment of constructions, construction units and components of machines and mechanisms are disclosed. The invention provides high reliability of magnetostrictive transducers, oscillating systems and their components, tools and their parts affected by simultaneous action of static, dynamic and impact load on a work surface, high stability of characteristics and interchangeability thereof under conditions of small-scale, full-scale and mass production. The invention also includes design solutions with the use of new methods of the realization and manufacturing technique of the above.

The present invention relates to a machining equipment, in particular, it relates to a cutting automatic machining equipment. Said machining equipment is characterized by that its cutting-tool is mounted on a supermagneto-striction transducer, said supermagnetostriction transducer is mounted on a machine frame guideway by means of carriage, and utilizes a control equipment to simultaneously implement feeding movement and ultrasonic frequency vibration. Said invention can implement material-removing machining and ultrasonic surface burnishing processing operation so as to raise production efficiency.

The present invention relates to a method and an apparatus for structural diagnosis, which generates torsional waves upon a shaft, beam or pipe having arbitrary cross-sections, such as a circular cross-section, and senses existence or location of the cracks through analyzing reflected waves. The present invention provides a magnetostrictive transducer comprising a plurality of ferromagnetic strips attached, around circumference of a member having an arbitrary cross-section with a fixed inclination; a first housing disposed to surround the ferromagnetic strips, the first housing being made of insulating material; and a coil wound around the first housing. The magnetostrictive transducer according to the present invention can generate torsional waves upon a member when a current is supplied to the coil, and can measure reflected torsional waves. Further, the present invention provides an apparatus and a method for structural diagnosis using the magnetostrictive transducer.

The invention discloses a sub-ultrasonic high-frequency fatigue testing machine. An energy converter used as a driving force source, the energy converter, a tested sample and a driven amplitude transformer form a resonance system, and a prearranged static loading mechanism provides static load for a test piece. The energy converter can be a full-wavelength energy converter or a half-wavelength energy converter. The energy converter converts an electric signal into mechanical vibration under the driving of an external alternating voltage, so the whole system is in a resonance state, and the tested sample has resonance vibration and a stress, thereby the fatigue detection can be realized. The energy converter can be a piezoelectric energy converter or a giant magnetostrictive energy converter. The sub-ultrasonic high-frequency fatigue testing machine allows the sub-ultrasonic high-frequency fatigue tests of the test piece under different stress ratios to be carried out according to the system prearrangement state; compared with traditional high-frequency fatigue testing machines, the sub-ultrasonic high-frequency fatigue testing machine has the advantages of simple structure, small volume, test period shortening, high efficiency and energy saving; and compared with present ultrasonic fatigue testing machines, the sub-ultrasonic high-frequency fatigue testing machine has the advantage of reduction of the frequency effect and the dimension effect to the material fatigue performances.

Magnetostrictive transducers for monitoring wall thinning in a pipe, and an apparatus and method for monitoring wall thinning in a pipe using magnetostrictive transducers are provided. The magnetostrictive transducers generate broadband multimode shear horizontal (SH) waves, and allow the generated SH waves to travel along the pipe, thus correctly monitoring a status of the wall thinning of the pipe. The apparatus includes a transmitting transducer which is installed outside of a pipe and generates shear horizontal (SH) waves traveling along the pipe, a receiving transducer which is spaced apart from the transmitting transducer and measures the shear horizontal (SH) waves traveling along the pipe, and a controller for monitoring wall thinning of the pipe by exciting and measuring output signals of the transmitting and receiving transducers.

The invention relates to a structure defect rapid nondestructive test apparatus under a high speed railway and a method thereof. A signal emission unit, a signal receiving unit, a giant magnetostrictive transducer and a hub-type vibration sensor are arranged on a track monitoring vehicle; an output terminal of a vibration control signal of a processor is connected with a signal input terminal of the giant magnetostrictive transducer through the signal emission unit, the signal output terminal of the hub-type vibration sensor is connected with the signal input terminal of the signal receiving unit, the signal output terminal of the signal receiving unit is connected with the signal input terminal of an analog-to-digital conversion system, the signal output terminal of the analog-to-digital conversion system is connected with a vibration reflection signal input terminal of the processor, when the hub-type vibration sensor detects the railway track on the track monitoring vehicle, the hub-type vibration sensor is rolled on a to-be-detected ballastless track plate and detects the vibration signal reflected by the to-be-detected ballastless track plate. The structure defect rapid nondestructive test apparatus does not require a coupling agent, and has the advantages of simple structure and strong environment adaptation, and can realize rapid structure defect scanning under ballastless track on the high speed railway.

The invention relates to a finishing process technology, in particular to an ultrasound magnetic force composite efficient finishing process device. The ultrasound magnetic force composite efficient finishing process device solves the problems that the applied range of an existing finishing process technology is small, processing efficiency is low, abrasive materials cannot be collected easily and the structure is complex. The ultrasound magnetic force composite efficient finishing process device comprises a working table, a guide rail, a tailstock, a giant magnetostrictive transducer, a clamp, a cylindrical workpiece, a magnetic field generating device, a large belt pulley, a V belt, a fixed support, a small belt pulley and a motor. The magnetic field generating device comprises a ring-shaped magnetic yoke, a tile-shaped permanent magnet pole, a magnetic grinding tool, a sleeve and an end cover. The giant magnetostrictive transducer comprises a rear end cover, a pre-tightening nut, a pressure block, a cooling water inlet, a cylindrical casing, a cylindrical coil stand, a front end cover, a pressure rod, an excitation coil, a cooling water outlet, a pre-tightening spring and a cylindrical rare earth giant magnetostrictive rod. The ultrasound magnetic force composite efficient finishing process device is suitable for finishing process of various mechanical parts.

The present invention provides a double-layer sector array folded coil structure integrated in a flexible circuit board, and designs and develops an arrayed omnidirectional type horizontal shear modal magnetostrictive transducer. Based on the magnetostrictive effect of ferromagnetic material nickel, the transducer realizes excitation of omnidirectional horizontal shear modal SH wave in the plate structure. Test verifies that the developed arrayed omnidirectional type horizontal shear modal magnetostrictive transducer can excite single SH0 modal waveguide inaluminum plate, and verifies that the developed omnidirectional type horizontal shear modal magnetostrictive transducer has better frequency response characteristics. The developed omnidirectional type horizontal shear modal magnetostrictive transducer and an array combined imaging algorithm can achieve efficient defect imaging on plate structure in wide range and board structure, and has very great value and potential in health monitoring and non-destructive evaluation of the plate structure.

The invention discloses a giant magnetostictive ultrasonic spindle which comprises a stem, wherein a secondary winding is fixed by the stem through a screw a; electric energy is conducted to the secondary winding from a primary winding; a bearing is arranged between the secondary winding and the primary winding; a positioning pin is arranged on the primary winding; a positioning block is insertedinto the positioning pin; the positioning block is connected with an ultrasonic wave generator through a lead; the center of a giant magnetostictive telescopic rod is hollowed, is subjected to axial slicing treatment and is further stuck by using an epoxy resin; in addition, a stripy hole is communicated with a through hole c; the lead is wound on the giant magnetostictive telescopic rod; direct current is overlapped in an excitation coil to provide an offset magnetic field; a rear cover plate, the giant magnetostictive telescopic rod and an amplitude variable rod are fastened through pre-tightening bolts; the stem is connected with the amplitude variable rod through a screw b; the amplitude variable rod is connected with a tool head through an elastic clamp; a gap is formed between the stem and the rear cover plate. By adopting the giant magnetostictive ultrasonic spindle, the problem that a giant magnetostictive ultrasonic transducer radiates heat in practical processing can be effectively solved.

The present invention is a high-performance magnetostrictive transducer of using multi-layer winding coil, belonging to acoustics sensor technology field. The invention utilizes permanent magnet to generate bias magnetic field around the sensor, adding alternating voltage onto two terminal of enameled wire will generate alternating magnetic field on the stranded steel wire, because of theferromagnetic material has magnetostrictive effect that will produce partial mechanical vibration in the stranded steel wire, the vibration movement will spread from the excitation source to two directions simultaneity and being captured by the receiving sensor via magnetostrictive reaction. The solenoid surrounded by multi-layer enameled wire and between the two near layers are separated by black adhesive tape, the surrounding direction of each layer in the section between every two steps is identical, among the enameled wire surrounded is connected in parallel or series mode for inspiring and receiving signal. The invention resolves the present status of receiving signal of the magnetostrictive transducer in the stranded steel wire is in low breadth value and poor signal-noise ratio, improving the detection range and detection accuracy effectively.

The invention provides an abrasion test machine of erosion and cavitation erosion compound for liquid-solid two-phase flow. It sets the inner casing cover in the out steel cover in the same axis, the magneto striction transducer passes through the out and inner casing covers. The terminal installed the cavitation sample on the amplitude pole in one end of magneto striction transducer dips into the horizontal water jar which the parallel axis is installed with a hollow principle axis, which one end is connected with the principle axis; the other is installed with the erosion sampling pan. So it can provide the liquid-solid two-phase flow erosion condition and cavitation condition.

The invention discloses a double-rod type giant magnetostriction ultrasonic vibration device. The device comprises a knife handle, a variable amplitude rod and a tool head are sequentially connected to the lower end of the knife handle, a cavity is formed in the lower part of the knife handle, a giant magnetostriction transducer is arranged in the cavity, a sealing bearing, an elastic check ring and a sleeve are arranged on the outer side wall of the knife handle, the elastic check ring and the sleeve are used for fixing the sealing bearing, a shell is arranged outside the sealing bearing, anupper end cover and a lower end cover are arranged at the upper end and the lower end of the shell respectively, the outer side of the knife handle is also provided with a primary side winding and a secondary side winding, and the primary side winding and the secondary side winding are located below the shell in sequence. According to the double-rod type giant magnetostriction ultrasonic vibrationdevice, the problem of magnetic flux leakage of the giant magnetostriction transducer is solved.