32 results about "Elliptic motion" patented technology

The invention belongs to the technical field of cutting processing, and particularly discloses a vibration cutting device monitoring and control system based on a flexible piezoelectric sensor, comprising a cutting module, a signal detection module, a signal processing module and a feedback control module: the cutting module is used for cutting according to an elliptical motion track based on a preset vibration signal; the output end of the signal detection module is connected with the input end of the signal processing module and used for detecting vibration signals of the cutting module in real time. The output end of the signal processing module is connected with the input end of the feedback control module, and the signal processing module is used for analyzing and processing the vibration signals and identifying abnormal changes and interference factors in the vibration signals; and the output end of the feedback control module is connected with the input end of the cutting module, and the feedback control module is used for predicting a vibration signal of the cutting module at a future moment based on the abnormal change and the interference factor, generating a compensation signal based on an error between the predicted vibration signal and a preset target vibration parameter, and adjusting the vibration signal of the cutting module in real time.

The invention discloses a friction-force-adjustable dual-piezoelectric stick-slip driving platform and method capable of achieving rollback suppression, and belongs to the technical field of micro-driving precision positioning. The platform is mainly composed of a base, a crossed roller guide rail, a working sliding table, a ceramic friction plate, a grating ruler, a grating ruler reading head, a fastening screw and a driving transmission module. A flexible structure in the driving transmission module comprises two symmetrically-distributed variable-rigidity flexible beams, high-consistency bidirectional movement is completed by means of the parasitic movement principle, ordered excitation signals are cooperatively applied to enable contact points to execute an elliptic movement track, and rollback displacement is effectively reduced. The mode of combining initial pre-tightening and dynamic piezoelectric pre-tightening is provided, and friction force self-adaptive adjustment is achieved so as to adapt to different mass loads; large-stroke cross-scale sub-nanometer positioning is realized by adopting a double piezoelectric ceramic driving principle. According to the invention, the design requirement of a large-range and high-precision compatible driver can be met, large-stroke cross-scale sub-nanometer positioning can be realized, the output characteristic is ensured, the overall structure is compact, and the device is suitable for batch production.

The invention discloses a multi-degree-of-freedom piezoelectric motor stator structure, a piezoelectric motor and a driving method, and different voltage signals are applied to piezoelectric patches around a stator to excite first-order extension and multi-order bending modal motion, so that a driving foot of the stator generates elliptical motion, and further a mover is pushed to move. Based on the two-degree-of-freedom piezoelectric stator, the two-degree-of-freedom piezoelectric stator is suitable for plane multi-degree-of-freedom driving and rotation multi-degree-of-freedom driving, and the applicable range of the piezoelectric stator is greatly widened; and the two driving modes are simple in structure assembly design, and are suitable for a microminiature multi-degree-of-freedom precision driving system. As the motor can meet the driving requirements of planar and rotary driving occasions, the assembly design requirements of the motor are greatly reduced, and decoupling movement in different directions can be realized; according to the multi-degree-of-freedom driving mode based on the two-degree-of-freedom piezoelectric stator, the design flexibility is high, and the performance of the motor is effectively improved.

The invention belongs to the technical field of piezoelectric driving, and relates to a piezoelectric driver, a working method thereof and a driving mechanism. The piezoelectric actuator is mainly composed of a driving body, a driving foot, a pre-tightening force mechanism and a bolt. The driving body generates a non-resonance induction mode and brings first direction displacement and second direction displacement to be generated near a resonance mode under the excitation of a plurality of paths of driving electric signals due to the synergistic strain effect of a plurality of piezoelectric bodies, and the tail end of the driving foot forms an elliptical motion track through the synergistic effect of the displacements in two orthogonal directions. The driving mechanism comprises a piezoelectric actuator, a sliding block, a carrying platform and a fixing mechanism, the piezoelectric actuator is fixed to the sliding block and moves together with the sliding block during driving, a fixed piezoelectric actuator in a traditional scheme is converted into a moving part, and the advantages of being long in stroke and large in thrust are achieved. According to the invention, the beneficial effects of wide frequency band, large output and high-precision driving can be achieved, and miniaturization of a driving system is facilitated.

The invention provides a single-shaft elliptical vibration exciter capable of adjusting a motion trail, a vibrating screen and a feeder, and relates to the technical field of vibration exciters. The single-shaft elliptical vibration exciter is mainly composed of a motor, a bottom plate, a rotating shaft, an eccentric sliding block and an adjustable elliptical assembly, when the single-shaft elliptical vibration exciter works, the motor drives the rotating shaft to rotate, a rolling wheel abuts against the inner ring face of a deformation ring under the action of centrifugal force, the eccentric sliding block is forced to do elliptical motion in the radial direction of the rotating shaft, and the centrifugal force generated by the eccentric sliding block is transmitted to the bottom plate; and therefore, the bottom plate generates vibration with an elliptical motion trail. According to the vibration exciter, the oval shape of the inner ring face of the deformation ring can be adjusted at will, then the vibration exciter generates oval vibration meeting the material screening requirement, and the screening effect on different materials is effectively improved. Due to the fact that the shape of the inner ring face of the deformation ring is visible, the shape and the vibration angle of the elliptic motion trail can be specifically adjusted under the condition that the machine is not stopped. In addition, the invention has the characteristics of high energy efficiency ratio and long service life of the bearing.

The utility model discloses a three-rectangular-plate parallel connection type linear moving platform driven by a piezoelectric stator. The three-rectangular-plate parallel connection type linear moving platform comprises a support assembly, a stator assembly, a moving table assembly and a pre-tightening force adjusting assembly. The stator assembly is fixed on a boss of the base, and the top end of the triangular driving foot is in contact with the friction plate; a moving guide rail and a sliding block in the pre-pressure adjusting mechanism form a moving pair, a spring and a gasket are pressed between a pre-tightening bolt and a bolt bracket, and the tightness of the spring is controlled to realize the adjustment of the pre-tightening force between the triangular driving foot and the friction plate; when the linear moving platform device works, a specified electric signal is applied to the piezoelectric ceramic piece, a first-order longitudinal vibration mode and a second-order bending vibration mode of the stator assembly are excited at the same time, through coupling of the longitudinal vibration mode and the bending vibration mode, the triangular driving foot can generate elliptic motion, and under the action of pretightening force, through friction coupling between the driving foot and the friction plate, the linear moving platform device is driven to move. And the moving plate is pushed to linearly move. The utility model has the advantages of compact structure, simple installation and large thrust.

Various embodiments include a piezoelectric actuator for driving motion of a deformable lens. The piezoelectric actuator may include a frame coupled with piezoelectric elements. According to some embodiments, the piezoelectric elements may be activated to produce relative elliptical motion between portions of the frame. The relative elliptical motion may modulate friction between surfaces of the frame, so as to drive motion of at least a portion of the deformable lens.

The present invention discloses a mobile robot based on a multi-degree-of-freedom piezoelectric actuator and an excitation method thereof, wherein the piezoelectric robot includes a rotor, a stator, four connecting rods and four support members. The support member includes a limit cylinder, a spring and a support ball. The stator is wrapped around the outer surface of the rotor. The stator is made of piezoelectric ceramics. The present invention applies a specific combination of electrical signals to the stator to excite a radial bending vibration mode and two vibration modes of the stator in two orthogonal axial bending vibration modes, thereby coupling to form a slight elliptical motion on the driving surface, and driving the rotor to rotate around three axes through friction, thereby realizing translation and rotation in two directions of the piezoelectric robot. The present invention can realize translation and rotation in two directions, and has the advantages of simple and compact structure, no electromagnetic interference, self-locking when power is off, and easy miniaturization. It is suitable for fields such as robot transportation technology, target tracking technology and precision positioning platform.

The invention provides a single-shaft type vibration exciter with an elliptic motion trail and a vibrating screen, relates to the technical field of vibration exciters, and mainly aims to solve the problem that the elliptic motion trail and the vibration angle of a three-shaft vibration exciter in the prior art cannot be specifically adjusted. The single-shaft type vibration exciter is mainly composed of a motor, a rotating shaft, an eccentric sliding block, a replaceable oval template and a base, when the motor drives the rotating shaft to rotate, a rolling wheel abuts against an oval cylindrical surface under the action of centrifugal force, the eccentric sliding block is forced to do oval motion in the radial direction of the rotating shaft, and the centrifugal force generated by the eccentric sliding block is transmitted to the base; therefore, the base generates vibration with an elliptical motion trail. Due to the fact that the elliptic cylindrical surface is in an elliptic shape meeting the material screening requirement, and the installation angle of the elliptic cylindrical surface is adjustable, accurate control over the elliptic motion trail and the vibration angle can be visually and concrete achieved. In addition, the single-shaft type vibration exciter and the vibrating screen have the advantages of being high in energy efficiency ratio and long in bearing service life.

The invention discloses an automatic positioning vibration mixing and stirring device, and relates to the technical field of stirring devices, the automatic positioning vibration mixing and stirring device comprises a machine body, a Y-axis moving mechanism is movably connected in the machine body, a lifting mechanism is arranged on the inner side of the Y-axis moving mechanism, a vibration mechanism is arranged on one side of the lifting mechanism, and a fixing block is arranged on one side of the vibration mechanism. A motor in the lifting mechanism drives a toothed belt to enable a stirring needle to extend into a test tube, then a vibration mechanism is started, an eccentric wheel rotates to drive a driving piece and an impact block to do elliptical motion, meanwhile, an electromagnet enables the impact block to do up-and-down reciprocating motion to impact a vibration base and drive the stirring needle to do synchronous motion, and liquid in the test tube can be fully stirred; after stirring is completed, the lifting mechanism is lifted, the cleaning mechanism is started, cleaning disinfectant is input through the high-pressure pump, the outer wall of the stirring needle is cleaned in the vibration base, and the technical problems that liquid in the test tube is not fully mixed, the stirring device needs to be independently cleaned after stirring is completed, operation is complex, and the overall efficiency is low are solved.

The invention provides a patch type piezoelectric driving two-degree-of-freedom mechanical arm and a driving method thereof. The mechanical arm comprises a plurality of unit arm sections connected in sequence and connecting assemblies between the arm sections. During working, driving signals with pi / 2 phase differences are applied to the piezoelectric vibrators on the unit arm sections, so that the points, making contact with the adjacent piezoelectric vibrators, of the piezoelectric vibrators generate micro-amplitude elliptical motion, and driving force is generated through the friction effect; the rotation of the unit arm sections around the piezoelectric vibrators of the adjacent unit arm sections and the rotation of the unit arm sections around the axes of the piezoelectric vibrators of the unit arm sections can be realized respectively, and the two-degree-of-freedom rotation of the two arm sections in two orthogonal planes can be realized due to the fact that the unit arm sections and the adjacent unit arm sections are spatially orthogonal. The mechanical arm is easy to seal, microminiaturization is achieved, electromagnetic interference is avoided, self-locking can be achieved in the power failure process, modal coupling frequency consistency adjustment of different phase modals is not needed, and the limitation on the design size, shape and the like of the mechanical arm is reduced.

The invention discloses a multi-stator traveling wave driven hollow rotary ultrasonic motor and a method thereof. The hollow rotary ultrasonic motor comprises a base, a shell, a fixed ring, a stator module, a rotor and a rolling bearing, the stator module comprises a stator bracket and N stator units; the stator unit comprises first to second adjusting bolts, first to second adjusting springs, first to fourth fixing bolts, first to fourth fixing nuts, a stator seat, a metal substrate, first to fourth piezoelectric ceramic pieces, and first to fourth driving feet. During working, the stator units are excited by two-phase signals, so that the driving feet on the stator units generate elliptical motion to drive the rotor to rotate, and the effect of simulating traveling wave driving is achieved by controlling the phases of the signals received by the stator units. According to the invention, a multi-stator traveling wave driving mode is adopted, modular design is adopted, the stator is convenient to disassemble and replace, and the motor has the advantages of large size, large hollow space and the like.

The application discloses a cage type dynamic-rotor integrated piezoelectric actuator and a control method thereof. The actuator comprises three parts of a ring-shaped piezoelectric vibrator, a fixed holder and a circular arc slide rail. Two driving feet are symmetrically arranged on the outer side of the ring-shaped piezoelectric vibrator in the diametric direction, and two rotating shafts are arranged in the vertical direction. A plurality of piezoelectric ceramics are symmetrically attached to the grooves on the two sides of the circular ring. The working principle of the application is that two different vibrations are generated by the piezoelectric vibrator, and after coupling, an elliptical motion is output at the driving feet, and the rotation is driven through the reaction force of the friction. The application innovatively designs a stator-rotor integrated piezoelectric rotary actuator. The piezoelectric vibrator is not only a driving power source, but also a motion mechanism, so that the structure and function are integrated, an additional rotor and a fixing device are not needed, the overall structure of the actuator is simplified, and the weight of the actuator is reduced.

The invention discloses a novel underwater robot based on a patch type piezoelectric transducer, and relates to the field of piezoelectric driving. The device comprises a patch type piezoelectric transducer, a clamping structure, a base body, two tension springs, four bearings, a first axle, a second axle, four wheels and two bearing boxes. The patch type piezoelectric transducer is fixed between two vertical plates of the base body through a clamping structure, two wheel shafts of the wheel are clamped in wheel shaft holes of the base body through bearings and limiting gaskets, and two tension springs are hung on bolts on the two sides of the base body and are in a stretching state, so that two plane driving feet at the bottom of the piezoelectric transducer abut against the two wheel shafts. When the robot works, the patch type piezoelectric transducers are excited, the two plane driving feet at the bottoms of the patch type piezoelectric transducers generate elliptical motion in the same direction, the two wheel shafts are driven to rotate through friction, then the wheels are driven to rotate, and movement of the robot is achieved. According to the technical scheme, the problems that an existing underwater robot is large in size, complex in structure and difficult in dynamic sealing in the high-water-pressure environment are solved.

The invention discloses a vibration driving micro-robot for narrow environment detection based on machine vision, and belongs to the field of narrow area detection. Aiming at the problem that the narrow area is difficult to detect, the novel device is designed, the structure is simple, meanwhile, a self-powered micro power supply is carried, and the condition of the narrow area is uploaded to the cloud in real time through visual navigation flaw detection and visual defect analysis. The invention discloses a vibration-driven micro-robot for narrow environment detection based on machine vision. The vibration-driven micro-robot comprises a camera assembly 1, a robot main body assembly 2 and a robot leg assembly 3, by exciting a first-order bending vibration mode, the tail end of the leg forms an elliptical motion track, the amplitude, frequency and motor phase difference are adjusted through PWM waves, multiple motion modes are achieved, a battery is arranged in the main body module, an external power source is not needed, and a camera is carried to construct a whole-process closed-loop crack analysis system. And the method is of great significance in improving the application of the micro-robot in narrow area detection.

The invention discloses a camera focusing mechanism and module based on an ultrasonic micro-motor structure, and belongs to the field of camera focusing mechanism design, and the camera focusing mechanism comprises an ultrasonic micro-motor driven by a piezoelectric film, an inclined plane driven structure, a spring structure, and a housing provided with a notch structure and a housing projection structure. When the stator structure of the ultrasonic micro motor is excited and driven by an external signal to generate a standing wave or a traveling wave, the stator bulge structure does elliptic motion, and the elliptic motion pushes the friction layer, the magnetic material layer and the inclined plane driving structure in the rotor structure to do rotary motion; in the rotating process, the limiting column is matched with the notch structure, the degree of freedom in the rotating direction is restrained, the inclined face is driven by the driving structure to do linear motion in the optical axis direction, and the shell protruding structure and the outer edge of the rotor structure are used for achieving the limiting effect in the plane direction. According to the invention, higher adjustment precision and higher response speed can be realized, and the method is more beneficial to being embedded into a camera module structure applied to a mobile phone and other terminals.

The invention discloses a sandwich type piezoelectric driving seabed mobile robot and a working method thereof, the whole seabed mobile robot is bilaterally symmetrical, and the seabed mobile robot comprises a sandwich type piezoelectric vibrator, two driving wheel structures and a pre-tightening force applying module. Flexible hinges used for clamping are arranged on the four faces in the middle of the sandwich type piezoelectric vibrator, the front ends of the interiors of the two ends are conical faces, the rest are variable cross-section through holes, and all the parts of the sandwich type piezoelectric vibrator are pressed into a whole through bolts. The pre-tightening force applying module applies pre-tightening force by screwing the sleeve, and the thrust bearing and the rolling bearing bear tangential force and axial force of the output shaft. During working, two second-order bending vibration modes which are mutually orthogonal in space and have a pi / 2 phase difference in time are excited by giving a simple harmonic voltage signal to the piezoelectric ceramic group located at the maximum vibration mode, mass points on the inner conical surface of the output end of the piezoelectric vibrator do elliptical motion, and the driving wheel structure is driven to rotate through friction; the robot can advance or retreat by changing the phase difference of the simple harmonic voltage signals.

The application belongs to the technical field of vibrating screening devices, and discloses a single-machine driving energy-saving horizontal elliptical vibrating screen and a parameter determination method thereof. The single-machine driving energy-saving horizontal elliptical vibrating screen comprises a vibration exciter, an outer mass body, an inner mass body, a shearing rubber spring and a vibration isolation spring. The vibration isolation spring is connected to a foundation and a main mass body. The vibration exciter is located at the centroid of the outer mass body and is composed of an eccentric rotor and an induction motor. The vibration exciter rotates around the center of its rotation axis, thereby generating a vibration excitation force to make the inner mass body generate a certain vibration intensity. The movement track of the inner mass body is an elliptical movement. According to the use requirement, a corresponding number of inner mass bodies can be installed to improve the production rate and reduce the power consumption, thereby realizing the engineering application value.

The invention discloses a piezoelectric-driven bionic sea turtle underwater swimming robot and a control method thereof, relates to the field of underwater robots, and solves the problems of poor driving flexibility, high energy consumption and insufficient silence in the prior art. The robot comprises a main body driving assembly and anterior and posterior limb driving assemblies; the main body driving assembly comprises a main body piezoelectric vibrator composed of a main body piezoelectric vibrator base body and four ceramic pieces, the limb driving assembly comprises a limb piezoelectric vibrator composed of a limb piezoelectric vibrator base body and two ceramic pieces and a hydrofoil, and the limb piezoelectric vibrator and the hydrofoil are assembled in a pre-tightening mode through a tension spring. During control, the forelimb and the main body electric vibrator respectively apply two-phase simple harmonic signals with phase difference, and the two-phase simple harmonic signals cooperatively vibrate to generate relative elliptical motion to drive the hydrofoil to backwards push water to obtain propulsive force; then the limb position recovery is realized by the inverted main body piezoelectric vibrator; the robot continuously advances in a reciprocating alternating mode of propelling and recovering; a simple harmonic electric signal is applied to one of the two forelimbs to realize yawing movement of the forelimb. The robot is compact in structure, accurate in movement, low in consumption, mute and high in flexibility.

The present invention discloses an in-plane traveling wave type linear feeding device and its working method. The device includes a base, a first connecting piece, a second connecting piece, a front beam, a rear beam, a middle beam, a first to fourth piezoelectric unit, a first to second pre-tightening bolt, a piezoelectric bimorph, a first to third stopper, and M + N + P adjusting bolts; during operation, a sine signal U1 is applied to the first piezoelectric transducer, and a sine signal U2 is applied to the second piezoelectric transducer. The frequencies and voltages of U1 and U2 are the same and have a phase difference of π / 4. The longitudinal vibration modes of the first piezoelectric transducer and the second piezoelectric transducer are excited, and the longitudinal vibrations with a phase difference of π / 4 are superposed to induce a traveling wave mode of the middle beam; in the traveling wave mode, the vibration form of a single particle on the middle beam is elliptical motion, so that the material placed on the middle beam moves in the direction of the traveling wave propagation under the friction force of the elliptical motion of each particle; adjusting the phase difference between U1 and U2 to -π / 4 can realize the reverse transportation of the material. The structure of the present invention is simple and the transportation stability is high.

The application discloses a high-viscosity fluid piezoelectric ultrasonic atomization device, which comprises a piezoelectric ceramic base, the bottom side of the piezoelectric ceramic base is fixedly connected with a piezoelectric ceramic, a variable amplitude plate is eccentrically fixed to the top side of the piezoelectric ceramic base and can amplify high-frequency vibration generated by the piezoelectric ceramic inverse piezoelectric effect, a plurality of pipe grooves are arranged at the end of the variable amplitude plate corresponding to vibration transmission, light holes communicating with the side walls of the pipe grooves are arranged at the two side ends of the variable amplitude plate, clamping limiting pieces are connected to the light holes and used for positioning metal liquid passing pipes in the pipe grooves, based on the eccentric layout of the variable amplitude plate, micro-elliptical motion can be formed at the vibration end of the variable amplitude plate, the high-viscosity fluid in the metal liquid passing pipe can alternately present positive pressure and negative pressure, and then transient cavitation and liquid flow are excited and generated, the application has the advantages of simple structure, convenient use, solution to the problem of effectively atomizing high-viscosity fluid at low cost and suitability for atomization scenes of high-viscosity fluid which cannot be diluted or atomized after being heated.

The invention provides a plate-shaped piezoelectric linear motor based on an in-plane first-order bending longitudinal mode, and belongs to piezoelectric motors. The motor is composed of a plate-shaped stator and a linear guide rail, the plate-shaped stator comprises a single driving foot made of wear-resistant materials and a vibrator body made of piezoelectric ceramics, and the linear guide rail is pressed on the single driving foot through pre-pressure. The oscillator body is provided with three (or'two ') polarization subareas, wherein the left polarization subarea and the right polarization subarea (or the left polarization subarea) form an A phase, and the middle polarization subarea (or the right polarization subarea) forms a B phase. Two orthogonal working modes of the stator are respectively an in-plane first-order bending vibration mode and a first-order symmetrical longitudinal vibration mode, two paths of sinusoidal signals with the phase difference of pi / 2 are applied to the A phase and the B phase of the stator, and the two orthogonal working modes of the stator are excited at the same time, so that mass points on the contact surface of the single driving foot generate elliptic motion, and a guide rail is driven through the friction effect. Compared with an existing piezoelectric motor, the motor adopts a low-order working mode, and the operation speed and the operation stability of the motor are higher.

The present invention relates to the technical field of elastic rubber detection, and discloses an elliptical motion mechanism and a simulated three-dimensional loading test device. The elliptical motion mechanism includes a workbench, in which a first adjustment mechanism, a second adjustment mechanism, and a third adjustment mechanism are arranged. The first adjustment mechanism includes a slider A, a screw A, a support A, and a pin A. The second adjustment mechanism includes a support B, a pin B, a screw B, and two sliding assemblies. The sliding assemblies include the slider B, a slide bar, and a rotating pin. The third adjustment mechanism includes a support C, a slider C, a screw C, and an output shaft. When power is input to rotate the pin A and the slider A, the third adjustment mechanism can output the motion of an elliptical trajectory on the output shaft, and the parameters of the output elliptical trajectory can also be adjusted. The three-dimensional loading test device includes the above-mentioned elliptical motion mechanism and a vertical actuator. It only requires two prime movers to simulate three-dimensional loading conditions, is relatively inexpensive, and has a simple control scheme.

The utility model discloses a piezoelectric driving device and a lens module, the piezoelectric driving device comprises a first piezoelectric element, a second piezoelectric element, an elastic piece, a friction piece and a carrier, the first piezoelectric element and the second piezoelectric element are respectively connected with the top surface and the bottom surface of the elastic piece; the bottom end of the friction piece is connected with the top face of the elastic piece, the top end of the friction piece abuts against the carrier, the first piezoelectric element and the second piezoelectric element jointly drive the top end of the friction piece to generate elliptic motion, and therefore the carrier is driven to move in the first direction. Through the comprehensive effect of the two motion modes of the first piezoelectric element and the second piezoelectric element, the top end of the friction piece can generate elliptical motion, and therefore the carrier is driven to move in the first direction. The structure of the piezoelectric driving device is simplified, the precision requirement of parts is lowered, and the cost can be reduced during large-scale production.

The application discloses a patch type spherical rotor multi-degree-of-freedom ultrasonic motor and an excitation method thereof. The ultrasonic motor comprises a piezoelectric vibrator, a base, a spherical rotor and a pre-tightening module. The piezoelectric vibrator comprises a stator and a piezoelectric ceramic sheet. The stator comprises a first base body, a second base body and first to fourth driving feet. The base comprises a fixing cylinder and a web. The pre-tightening module comprises a threaded rod, a bearing, a bearing seat, a clamping hemisphere, a spring, a pre-tightening nut and a gasket. Different excitation signals are applied to the piezoelectric ceramic sheet, so as to excite two modes of an axial symmetric bending mode and two orthogonal axial bending modes of the stator, thereby coupling to form a micro-elliptical motion on the four driving feet, and the spherical rotor is driven by friction to rotate in three degrees of freedom. The application can realize three degrees of freedom rotation, has the advantages of adjustable pre-pressure, simple and compact structure, no electric self-locking, easy miniaturization and the like.

The present invention discloses a three-degree-of-freedom piezoelectric actuator and its working method. The piezoelectric actuator includes a piezoelectric vibrator, a spherical rotor, a clamping frame, and first to fourth connecting rods; the piezoelectric vibrator includes a stator and first to eighth piezoelectric ceramic sheets. By applying excitation signals with a specific combination to the first to eighth piezoelectric ceramic sheets, two vibration modes out of one radial bending vibration mode and two orthogonal axial bending vibration modes of the stator are excited, so as to couple and form a micro-amplitude elliptical motion on the driving surface of the stator, and the spherical rotor is driven to obtain rotational motion in three degrees-of-freedom directions by using the frictional force. The present invention can achieve rotational motion in three degrees of freedom, has the advantages of simple structure, power-off self-locking, and easy miniaturization, and is applicable to fields such as space pointing mechanisms, optical target tracking, and robot joint technologies.

The present invention discloses a dual-rotor rotary piezoelectric motor, belonging to the field of piezoelectric actuators. The motor drives the rotor to perform rotary motion by controlling different deformation modes of the flexible beam, achieving independent control of the speeds and output torques of the two rotors of the motor respectively. In the present invention, piezoelectric ceramics are pasted on the surface of the flexible beam with driving feet to form a piezoelectric stator. Different-phase and different-frequency alternating voltages are applied to multiple piezoelectric ceramics respectively. The inverse piezoelectric effect of the piezoelectric ceramics is utilized to stimulate the stator to generate different deformations, so that the end parts of the driving feet on the surface of the flexible beam generate elliptical motion trajectories to drive the two coaxial rotors to perform rotary motion. Four groups of stators are evenly installed on the base, and the independent control of the rotational speeds and output torques of the two rotors is achieved by using different driving modes of the four groups of stators.

For a piezoelectric actuator used to linearly drive a driven element by inducing elliptical motion in a vibrating element through vibration of the piezoelectric element, a drive device is provided that improves control at very low speeds and / or enables the use of a smaller boost circuit to provide the drive voltage for the piezoelectric actuator. According to one embodiment, a drive device for axially driving a driven element is provided. The driving device includes: a piezoelectric actuator, wherein the piezoelectric actuator includes a vibrating element in contact with a driven element and one or more sets of piezoelectric elements attached to the vibrating element; and a controller, wherein each set of piezoelectric elements includes one or more piezoelectric elements, and in each set of piezoelectric elements, a first electrode for expanding or contracting a first region of the piezoelectric element in the set of piezoelectric elements and a second electrode for expanding or contracting a second region of the piezoelectric element in the set of piezoelectric elements are arranged along the axial direction, wherein in each set of piezoelectric elements, a common third electrode or a separate third electrode paired with the first electrode and the second electrode is provided, such that the vibrating element of the piezoelectric actuator has: a bending mode, wherein the middle portion along the axial direction becomes convex or concave, thereby causing the ends of the vibrating element to move along the axial direction at both ends; and an expansion / contraction mode, wherein one end expands / contracts at both ends of the axial direction, while the other end expands / contracts with opposite phases over time, thereby causing the ends of the vibrating element to move in a direction perpendicular to the axial direction. The controller is used to cause the vibrating element to vibrate by applying oscillating voltage signals of the same frequency to the first and second electrodes, thereby driving the driven element in contact with the vibrating element along the axial direction. When the oscillating voltage signals applied to the first and second electrodes are in phase, a first mode of vibration based on the bending mode is generated in the vibrating element; when the oscillating voltage signals applied to the first and second electrodes are in opposite phase, a second mode of vibration based on the expansion / contraction mode is generated in the vibrating element, wherein the controller is used to control the speed of the driven element by controlling the phase difference between the voltage signals applied to the first electrode and the voltage signals applied to the second electrode. Another aspect of the invention provides a small boost circuit for providing a drive voltage for a piezoelectric actuator.

The vibrating screen (PV) has a screen platform (11), two side walls (12) and a mechanical vibrator (VM) which consists of two members (20), which rotate at the same rotation and in opposite directions, where each of the end sections (20a) of each member (20) carries an eccentric weight (30) and is supported on bearings (21) which are supported on the side walls (12) of the vibrating screen (PV). The members (20) have their end portions (20a), one next to the other, which are supported on bearings (40) which are fixed to a same bearing housing (50) which is fixed to beams (13), transverse and with opposite ends fixed to the side walls (12) of the vibrating screen (PV).Each end portion (20a) of one member (20) carries an eccentric weight (30) with a total mass different from that of the eccentric weights (30) of the end portions of the other member (20), said members (20) rotating in defined phases, defining the inclination of the main axis of an elliptical movement which is transmitted to the sieve platform (11).

The invention discloses a novel underwater robot based on a sandwich type piezoelectric transducer, and relates to the field of piezoelectric driving. The device comprises a sandwich type piezoelectric transducer, a clamping structure, a base body, two tension springs, four bearings, a first axle, a second axle and four wheels. The sandwich type piezoelectric transducer is fixed between two vertical plates of the base body through a clamping structure, two wheel shafts of the wheel are clamped in wheel shaft holes of the base body through bearings and limiting gaskets, and two tension springs are hung on bolts on the two sides of the base body and are in a stretching state, so that two plane driving feet at the bottom of the piezoelectric transducer abut against the two wheel shafts. When the robot works, the sandwich type piezoelectric transducer is excited, the two plane driving feet at the bottom of the sandwich type piezoelectric transducer generate elliptical motion in the same direction, the two wheel shafts are driven to rotate through friction, then the wheels are driven to rotate, and movement of the robot is achieved. According to the technical scheme, the problems that an existing underwater robot is large in size, complex in structure and difficult in dynamic sealing in the high-water-pressure environment are solved.