50results about How to "High electromechanical coupling efficiency" patented technology

A vibrator of a beam type linear ultrasonic motor using bending vibration modes belongs to the technical field of piezoelectric ultrasonic motors and is used for the piezoelectric ultrasonic motors. The vibrator solves the problem that the mechanical output capabilities of the ultrasonic motors are restricted because of low tensile strength and low electromechanical coupling efficiency of ceramic materials in the prior art. The vibrator comprises two driving pads, two end covers, two insulating sleeves, two pairs of piezoelectric ceramics with polarization directions being thickness directions, a flange, two thin-walled beams and mounting bases; wherein, studs extend out from the end faces of the flange along the axis of the flange; each stud is sleeved with a pair of piezoelectric ceramics; an end cover is screwed at the overhanging end of each stud; the tail end of each end cover is provided with a driving pad; each piezoelectric ceramic is composed of two symmetrical half piezoelectric ceramics which are combined after being split; the polarization directions of the two half piezoelectric ceramics are opposite; the splitting lines of the two pairs of piezoelectric ceramics at both sides of the flange are vertical to each other; the polarization directions of the piezoelectric ceramics in each pair are opposite.

The invention discloses a T-shaped linear ultrasonic motor oscillator, which relates to the technical field of a piezoelectric ultrasonic motor and aims at solving the problem that the mechanical output capacity of the prior ultrasonic motor stator is limited. T-shaped front end covers of the T-shaped linear ultrasonic motor oscillator are combined by small end surfaces of three amplitude rods and are arranged in a T shape, a drive foot is connected with a connection position of the amplitude rods, and the three amplitude rods and the drive foot form an integral member; piezoelectric ceramics are polarized along the thickness direction, and opposite to the polarization direction of every adjacent two pieces of piezoelectric ceramics on the same amplitude rod, the polarization ways of the piezoelectric ceramics of two amplitude rods on the same axial line are opposite, each fastening screw passes through a back end cover, the piezoelectric ceramics and a flange and is connected to a blind hole, and the piezoelectric ceramics and the flange are positioned between the back end cover and the amplitude rod, and a piece of electrode plate is arranged between the piezoelectric ceramics and the flange; and an insulating sleeve is fixed outside the fastening screw. The invention is applied to the manufacture field of the ultrasonic motor.

The invention relates to an air-coupled capacitive micromachining ultrasonic transducer, a preparation method and application. A transducer array comprises 16 array elements; each array element is formed by multiple sensing units; each sensing unit is structurally formed by an upper electrode 1, a vibrating diaphragm 2, a cavity 3 and a base 5 sequentially from top to bottom; and each base is usedas a lower electrode. The working frequency of the designed transducer is 100kHz to 2MHz. The transducer array is manufactured based on an SOI bonding process; each vibrating diaphragm is made of monocrystalline silicon; each upper electrode is gold or aluminum; an insulating layer 4 is silicon dioxide or silicon nitride; and the array elements of the transducer are divided through etching the low-resistance-silicon bases to form grooves, so that the array with the multiple array elements is formed. According to the air-coupled ultrasonic transducer, an ultrasonic wave in a metal plate or a composite plate is excited through an air coupling manner and is used for nondestructively detecting internal defects of the plate. The transducer is matched with a phased array system, and pulse drivesignals of the array elements are delay-controlled, so that the phase-controlled deflection and the focusing of an acoustic beam are adjusted, and the freedom degree of detecting is increased.

The invention relates to a sandwich disk stator and an ultrasonic motor which uses the stator, which relate to the technical field of piezoelectric ultrasonic motors. The sandwich disk stator and the ultrasonic motor solve the problem in an existing ultrasonic motor that since a mode that a metallic elastomer is pasted with a piezoelectric ceramic slice is adopted to actuate, the mechanical output ability is restricted. Driving elements with even number in the sandwich disk stator are fixed on the upper end surface of a disk, two pairs of piezoelectric ceramic pieces are fixed between each pair of cantilever beams, and a plurality of comb-shaped driving gears are evenly distributed on the lower end surface of the disk. The ultrasonic motor which uses the stator comprises two stators, a rotor component is composed of a rotor and a wear resistance bush ring, wherein the end surface of the wear resistance bush ring is provided with same taper with the upper end surface of the driving gears, two stators are respectively installed on and under the rotor, the pre-tightening between the stator component and the rotor component can be realized through two stator flanges, and the rotor component is connected with bearing blocks of the two stators through output shafts and bearings on two ends of the rotor in a rotary mode. The sandwich disk stator and the ultrasonic motor have simple structure, can realize big force moment output, and have stable performance.

The invention relates to a cantilever longitudinal-bending composite transducer type cylindrical traveling-wave ultrasonic motor vibrator belonging to the technical field of piezoelectric ultrasonic motors and solving the problems that the mechanical output capability of a motor is restricted because the prior ultrasonic motor vibrator adopts a metal elastic body to bond piezoelectric ceramic thinplates to excite, and the mechanical output capability and the controllability of an ultrasonic motor are lowered because a plurality of transducers are simultaneously driven. The cantilever longitudinal-bending composite transducer type cylindrical traveling-wave ultrasonic motor vibrator comprises a cylinder and a cantilever longitudinal-bending composite sandwich transducer which are connectedinto a whole by two cantilevers, a fastening screw is fixedly screwed with a rear end cover after passing through central through holes of a front end cover and the two cantilevers, four longitudinalvibration piezoelectric ceramic plates are arranged between the two cantilevers, two pairs of bending vibration piezoelectric ceramic plates are respectively arranged between the front end cover andthe first cantilever and between the rear end cover and the second cantilever, and the adjacent bending vibration piezoelectric ceramic plates and the adjacent longitudinal vibration piezoelectric ceramic plates have opposite polarization directions. The cantilever longitudinal-bending composite transducer type cylindrical traveling-wave ultrasonic motor vibrator is used for the field of manufacturing ultrasonic motors.

The invention discloses a flexural vibration sandwiched energy converter-typed round disc stator and an ultrasonic motor to which the stator is applied, and relates to the ultrasonic motor field. The invention solves the problem in the existing ultrasonic motor, that mechanical output capacity is restrained due to the adoption of elastic metal body stuck on piezoelectric ceramic pieces for excitation. Even flexural vibration sandwiched energy converters of the stator are symmetrically arrayed and fixed between a round disc at the upper end and a round disc at the lower end; both the front end cover and the back end cover of the sandwiched energy converter are a quadrangular with a rectangle cross section narrowing down gradually, the small end faces of the front end cover and the back end cover are fixedly connected with the upper round disc and the lower round disc; two pairs of piezoelectric ceramic pieces are respectively and fixed between the front end cover, the back end cover and the flange. A rotor with a shaft and a rotor without a shaft in the ultrasonic motor both take the shape of a round disc and are embedded respectively from the top and the bottom of a stator cylinder, a wearable cushion is fixed at the end face, contacting the round disc, of the rotor and the stator is fixed to a base through the flange on the energy converter. The flexural vibration sandwiched energy converter-typed round disc stator and the ultrasonic motor of the invention are applicable to the manufacturing field of the ultrasonic motors.

The invention provides a rotary motor using composite bending vibration biped linear ultrasonic oscillators, belonging to the technical field of piezoelectric ultrasonic motors. The invention solves the problems that the existing patch type rotary piezoelectric ultrasonic motor has low coupling efficiency, and the mechanical output capability is difficult to improve. The rotary motor provided by the invention comprises n oscillators, a rotor assembly, a base, n plate springs, n pre-pressing screws and 4n baffle plates, wherein n is a positive integer; the center of the base is provided with a central through hole and a bearing seat; the rotor assembly is arranged in the central through hole; n rectangular section slots are uniformly distributed on the base along the outer circumference direction of the bearing seat; one oscillator is arranged in each rectangular section slot; one plate spring is also arranged in each rectangular section slot; and the two ends of each plate spring are respectively connected fixedly with two installing seats of the oscillator positioned in the rectangular section slot. The rotary motor provided by the invention can realize large-torque output.

The invention relates to a U-type double-pin linear ultrasonic motor vibrator, which relates to the field of piezoelectric ultrasonic motors and solves the problem of limited output capability of the prior mechanism. The U-type double-pin linear ultrasonic motor vibrator is characterized in that a vertical horn and a horizontal horn which are connected with end covers are of quadrangular prisms having rectangular sections and gradually thinning; big end faces of the vertical horn and the horizontal horn are provided with blind holes; driving pins are cuboids, the upper end faces of the driving pins are connected with a small end face of the vertical horn, and the upper parts of the side faces of the driving pins are connected with a small end face of the horizontal horn; flanges are provided with double-screw bolts which are fixedly connected with the blind holes and are sleeved with two pieces of piezoelectric ceramic plates; two independent end covers have the same structure and comprise double-screw bolts which are fixedly connected with the blind holes and are sleeved with four pieces of piezoelectric ceramic plates; all the piezoelectric ceramic plates are polarized along the thickness direction, the polarization directions of adjacent piezoelectric ceramic plates are opposite to each other, and electrode slices are arranged on positions applying driving signals; and the double-screw bolts of the flanges and the independent end covers are sleeved with insulation bushes. The invention is applied to the field of motors and has the advantages of high electromechanical coupling efficiency and large momental output.

The invention provides a bend-twist coupling type piezoelectric driving track traveling device and a working method thereof. The device comprises a metal track, two annular components and a variable cross-section piezoelectric transducer, wherein the annular components are arranged at two ends of the variable cross-section piezoelectric transducer; the variable cross-section piezoelectric transducer comprises a plurality of sets of piezoelectric ceramic pieces, two pre-tightening wedge blocks and a variable cross-section beam; and the piezoelectric ceramic pieces are arranged in a certain order and are fixed in a groove of the variable cross-section beam through the pre-tightening wedge blocks. According to the bend-twist coupling type piezoelectric driving track traveling device and the working method thereof, by stimulating the piezoelectric ceramic pieces, a torsional vibration mode and a bending vibration mode are stimulated on the variable cross-section beam, so that a traveling wave, with n (n being greater than or equal to 2) wave crests and wave troughs shown all together, rotating along the peripheral direction is coupled on the annular components, the mass points on the outer surfaces of the annular components carry out micro-amplitude elliptical motions and drive the metal track to move through the action of friction, and the device has the advantages of compact structure, large force (torque) weight ratio, high environmental suitability, structure form flexibility, high speed, high electro-mechanical coupling efficiency and the like.

The invention relates to a bending vibration sandwich transducer type disk double rotor ultrasonic motor which relates to the technical field of piezoelectric ultrasonic motors. The ultrasonic motor solves the problem in an existing ultrasonic motor that the mechanical output ability is restricted and a single stator only can realize single movement output. The bending vibration sandwich transducer type disk double rotor ultrasonic motor of the invention comprises a stator component, an upper end rotor component, a lower end rotor component, an upper end outer cover, a lower end outer cover, a rotated bearing, a bearing pre-tightening end cap and a bearing support, wherein continuous comb-shaped driving gears are manufactured on the upper end surface of a disc, a wear resistance bush ring is fixed on the end surface of an upper end disc rotor, which is contacted with the disk, the wear resistance bush ring is fixed on the end surface of a lower end disc rotor, which is contacted with the small end surface of a rear end cap, an upper end output shaft and a lower end output shaft are connected with the bearing block through a bearing in a rotary mode, the upper end outer cover and the lower end outer cover are respectively fixed on the upper end surface and the lower end surface of a cylinder flange, and thereby the upper end outer cover and the lower end outer cover are coaxial with the disk. The bending vibration sandwich transducer type disk double rotor ultrasonic motor can be applied in the manufacture field of ultrasonic motors.

The invention relates to a CoFe2O4/PVDF composite bone scaffold and a preparation method thereof. The CoFe2O4/PVDF composite bone scaffold is prepared by the following steps: mixing and stirring ethanol suspension of CoFe2O4 and ethanol suspension of PVDF, performing solid-liquid phase separation on the obtained CoFe2O4/PVDF mixed suspension, drying and ball-milling the obtained solid phase to obtain composite powder, and performing selective laser sintering on the composite powder. According to the CoFe2O4/PVDF composite bone scaffold provided by the invention, remote non-contact electrical stimulation on bone cells can be realized by externally applying an alternating magnetic field, so that growth of osteoblasts and regeneration and reconstruction of defective tissues are promoted.