Showing papers on "Piezoelectric motor published in 2018"

Development of a Nonresonant Piezoelectric Motor With Nanometer Resolution Driving Ability

Abstract: A nonresonant-type piezoelectric motor with a precise driving ability was proposed. The operating principle of the proposed motor is different from the previous nonresonant piezoelectric motors using either the clamping and feeding mechanism (inchworm mechanism) or the inertia drive mechanism. An oblique linear motion formed by the hybrid of two bending motions of a sandwich transducer was used to push the runner step-by-step. Two square-wave voltages were applied to the horizontal and vertical PZT elements to obtain the desired oblique linear motion. The mechanism of the proposed piezoelectric motor was illustrated in detail. Then, transient analyses were performed by ANSYS software to simulate the motion trajectory and to find the response characteristics of the motor. Finally, a prototype was fabricated to verify the mechanism and to test the mechanical output characteristics of the proposed motor. Under the input square-wave voltages of 500 V $_{\text{p-p}}$ , the prototype achieved a step displacement of 5.96 μm, a maximum no-load velocity of 59.64 μm/s, and a maximum thrust of 30 N. This paper provides a new mechanism for the design of a nonresonant piezoelectric motor with long stroke and precise driving ability.

New design for inertial piezoelectric motors

Abstract: We have designed, implemented, and tested a novel inertial piezoelectric motor (IPM) that is the first IPM to have controllable total friction force, which means that it sticks with large total friction forces and slips with severely reduced total friction forces. This allows the IPM to work with greater robustness and produce a larger output force at a lower threshold voltage while also providing higher rigidity. This is a new IPM design that means that the total friction force can be dramatically reduced or even canceled where necessary by pushing the clamping points at the ends of a piezoelectric tube that contains the sliding shaft inside it in the opposite directions during piezoelectric deformation. Therefore, when the shaft is propelled forward by another exterior piezoelectric tube, the inner piezoelectric tube can deform to reduce the total friction force acting on the shaft instantly and cause more effective stepping movement of the shaft. While our new IPM requires the addition of another piezoelectric tube, which leads to an increase in volume of 120% when compared with traditional IPMs, the average step size has increased by more than 400% and the threshold voltage has decreased by more than 50 V. The improvement in performance is far more significant than the increase in volume. This enhanced performance will allow the proposed IPM to work under large load conditions where a simple and powerful piezoelectric motor is needed.

Chosen Analysis Results of the Prototype Multicell Piezoelectric Motor

Abstract: This paper presents the design, modeling, and tests of the prototype multicell piezoelectric motor (MPM). A new concept of the electromechanical structure of the considered prototype is based on three rotating-mode actuators. The electromechanical structure of each actuator has been considered as an independent one—referred to as a “single cell” (single actuator). Combined three resonant actuators generate three traveling waves that as a result improve the stability and performance of the MPM. The results of research carried out using analytical, simulation, and experimental methods cover the torque versus speed characteristics of the prototype MPM.

Torque modeling and characteristic analysis of electromagnetic piezoelectric hybrid-driven 3-degree-of-freedom motor:

Abstract: The electromagnetic piezoelectric hybrid-driven 3-degree-of-freedom motor is a new multi-degree-of-freedom motor. To further analyze the torque characteristics of the electromagnetic piezoelectric ...

Development of a novel long range piezoelectric motor based on double rectangular trajectories driving

Abstract: This paper proposes a novel stepping type piezoelectric motor that can perform long range rotational motion with high resolution. Pseudo-rigid-body method is used to establish the kinematics model of the driving mechanism and analyze the motion trajectory of the driving foot. The static deformation of the driving mechanism is simulated by finite element analysis. In experiments, a motor prototype is fabricated and its performance is tested by the established experimental system. The results indicate that the motor prototype can work stably step by step and all steps have high reproducibility. The prototype can achieve 331.2 μrad maximum stepping angle at the driving voltage of 150 V and driving frequency of 1 Hz. The minimum stable stepping angle and the maximum output torque are 1.47 µrad and 76.44 mNm, respectively. The maximum angular velocity of the motor prototype is about 37,662.1 μrad/s when the driving voltage is 150 V and the driving frequency is 128 Hz. By applying proper driving voltage and frequency, the proposed piezoelectric motor can produce a satisfactory angular velocity.

Dynamic Modeling and Analysis of a Rotating Piezoelectric Smart Beam

Abstract: In active vibration control study, piezoelectric actuators and sensors are bonded on the surface of a beam. They can change the frequency and modal characteristics of the system. This paper presents an analysis of the frequency response to a rotating piezoelectric smart beam. Hamilton’s principle along with the assumed mode method are employed to derive the governing equations of the first-order approximate coupling model for the piezoelectric smart beam. The coupling is taken into account as the second-order coupling effect of the axial elongation caused by the transverse displacement of the beam. Then, the equations are transformed into a dimensionless form after identifying the necessary parameters. The dimensionless natural frequencies of the piezoelectric smart beam corresponding to the bending and stretching vibrations are obtained through a numerical simulation, with comparison made of those of the beam with no actuator or sensor. Furthermore, the implication is investigated of the structural parameters and bond location on the piezoelectric actuators and sensors. Besides, the common case of a smart beam bonded with multiple pairs of piezoelectric actuators and sensors is studied, and the effects of the first natural frequency and tip deformation are analyzed. The research provides a theoretical reference for the optimization of structural parameters and location of piezoelectric actuators and sensors, thereby preventing the resonance when the excitation frequency is approximately equal to the natural frequency of the beam.

Piezoelectric Motor Using In-Plane Orthogonal Resonance Modes of an Octagonal Plate

Abstract: Piezoelectric motors use the inverse piezoelectric effect, where microscopically small periodical displacements are transferred to continuous or stepping rotary or linear movements through frictional coupling between a displacement generator (stator) and a moving (slider) element. Although many piezoelectric motor designs have various drive and operating principles, microscopic displacements at the interface of a stator and a slider can have two components: tangential and normal. The displacement in the tangential direction has a corresponding force working against the friction force. The function of the displacement in the normal direction is to increase or decrease friction force between a stator and a slider. Simply, the generated force alters the friction force due to a displacement in the normal direction, and the force creates movement due to a displacement in the tangential direction. In this paper, we first describe how the two types of microscopic tangential and normal displacements at the interface are combined in the structures of different piezoelectric motors. We then present a new resonance-drive type piezoelectric motor, where an octagonal plate, with two eyelets in the middle of the two main surfaces, is used as the stator. Metallization electrodes divide top and bottom surfaces into two equal regions orthogonally, and the two driving signals are applied between the surfaces of the top and the bottom electrodes. By controlling the magnitude, frequency and phase shift of the driving signals, microscopic tangential and normal displacements in almost any form can be generated. Independently controlled microscopic tangential and normal displacements at the interface of the stator and the slider make the motor have lower speed–control input (driving voltage) nonlinearity. A test linear motor was built by using an octagonal piezoelectric plate. It has a length of 25.0 mm (the distance between any of two parallel side surfaces) and a thickness of 3.0 mm, which can produce an output force of 20 N.

Finite Element Study on Acoustic Energy Harvesting Using Lead-Free Piezoelectric Ceramics

Abstract: In this article, a numerical investigation is performed for ambient acoustic energy harvesting at a low-frequency acoustic signal. A model of a quarter-wavelength resonator with a rectangular cross section is constructed, and piezoelectric-laminated bimorph plates are placed inside the system. Finite element modeling is implemented to numerically formulate the piezoelectric energy harvester. With the application of acoustic pressure at the open end of the resonator, amplified acoustic pressure inside the tube vibrates the piezolaminated bimorphs inside the tube, thus generating electric potential on the piezoelectric layers. To generate higher voltage and power in the acoustic harvester, multiple piezolaminated plates are positioned inside the resonator. The lead-free piezoelectric material K0.475Na0.475Li0.05 (Nb0.92Ta0.05Sb0.03)O3 (KNLNTS) is laminated on the host structure as a layer of piezoelectric material for the acoustic energy harvester. With the application of an acoustic sound pressure of 1 dB at the opening of the tube, a maximum output voltage of 16.3 V is measured at the first natural frequency, while the maximum power calculated is 0.033 mW. Maximum voltage is obtained when five piezoelectric bimorphs are place inside the resonator. At the second natural frequency, the maximum voltage measured is 8.40 V, obtained when eight piezoelectric bimorphs are placed inside the resonator, and the maximum power calculated is 0.020 mW.

Dynamic optimization of an electromechanical integrated harmonic piezoelectric motor

Abstract: The coupled dynamic equations for an electromechanical integrated harmonic piezoelectric motor are proposed in this study. The vibration responses of the proposed motor are then determined using these equations. The mathematical models of dynamic optimization are established using the multi-objective optimization method. The optimal parameters are obtained through optimization. The vibration displacements are compared with the initial values. The effects of the parameters on the optimized amplitudes are also investigated. Results show that the vibration displacements of the piezoelectric motor decrease by over 89 % after dynamic optimization. These results can be used to improve the performance and decrease the vibration of the piezoelectric motor.

An L-shaped ultrasonic linear piezoelectric motor with two second-order bending coupling modes

Abstract: In order to simplify the motor structure, reduce the difficulty of modal coupling and obtain a wide driving frequency range, a new piezoelectric motor which works on the two second bending vibratio...

Driving device, piezoelectric motor, electronic component conveyance apparatus, and robot

Abstract: A driving device includes a plurality of motive power generators that receive electric power supply and generate motive power, the plurality of motive power generators form a plurality of sets of motive power generators in which two or more of the motive power generators are electrically parallel-connected, and the plurality of sets of motive power generators are electrically series-connected. A driving device includes a plurality of vibrators that receive electric power supply and vibrate and provide drive power for driving a driven member to the driven member, the plurality of vibrators form a plurality of sets of vibrators in which two or more of the vibrators are electrically parallel-connected, and the plurality of sets of vibrators are electrically series-connected.

Double-drive foot-type linear piezoelectric motor and electric excitation method

Abstract: The invention provides a double-drive foot-type linear piezoelectric motor and an electric excitation method, which belongs to the field of piezoelectric motors. The double-drive foot-type linear piezoelectric motor comprises a stator, a mover, a base and a mounting base. The mover is slidably connected with the base. The stator comprises a first driving foot and a second driving foot, wherein thefirst driving foot and the second driving foot are used for driving the mover to slide forward or backward in the sliding direction. The stator further comprises a frame part. The frame part is provided with a mounting space used for mounting the first driving foot and the second driving foot. The first driving foot is provided with a first driving side. A first piezoelectric laminate is arrangedbetween the first driving side and the frame part. A second piezoelectric laminate is arranged between the second driving side of the second driving foot and the frame part. A third piezoelectric laminate is arranged on the first end of the first driving foot. A fourth piezoelectric laminate is arranged on the second end of the second driving foot. The third piezoelectric laminate and the fourthpiezoelectric laminate are connected with a weight respectively. The double-drive foot-type linear piezoelectric motor has the advantages of high precision, low cost and long service life.

Friction material used for piezoelectric motor and preparation method and application thereof

Abstract: The invention discloses a friction material used for a piezoelectric motor and a preparation method and an application thereof. The friction material comprises the following raw materials: polytetrafluoroethylene, polyether-ether-ketone, polybenzoate, carbon fiber, and glass fiber, wherein the feeding mass ratio of polytetrafluoroethylene to polyether-ether-ketone to polybenzoate to carbon fiber to glass fiber is 4-11: 0.5-3:1:0.5-4:0.5-3; The preparation method comprises the following steps: 1) mixing the raw materials according to a formula amount, drying a mixture, and crushing the mixture;2) performing cold press molding on the processed mixture obtained in the step 1), and demoulding to obtain a friction material prefabricated product; and 3) performing sintering molding on the prefabricated product to obtain the friction material. The invention also provides an application of the friction material in the piezoelectric motor. The friction material can achieve excellent effects onfriction coefficient and hardness, can improve the easy tooth trapping and starting difficulty of the friction material, and increases the stalling torque of the friction material.

In-site sample rod of three-dimensional mechanic-electric transmission electron microscope

Abstract: The invention discloses an in-site sample rod of a three-dimensional mechanic-electric transmission electron microscope. The in-site sample rod comprises a sample rod front end, a sample rod shell anda handle, wherein a transmission rod and a piezoelectric ceramic pipe are arranged in the sample rod shell, a differential head rough regulator is arranged on the handle and is used for adjusting a transmission rod to radially move, one end of the transmission rod is connected with the piezoelectric ceramic pipe, a piezoelectric motor is arranged in the handle and is coaxially connected with theother end of the transmission rod, and a transmission rod support point is arranged on the sample rod shell. With the adoption of a mode combining rough regulation and fine regulation, millimeter-level rough moving and nanoscale fine moving can be respectively achieved, the sample loading problem is solved, the moving of a probe within a three-dimensional large range of XYZ is also achieved, the stability of a front-end probe is improved, and the displacement accuracy of the probe is further improved.

L1B2 Piezo Motor Using D33 Effect

Abstract: In this study, we introduce a new first longitudinal and second bending mode (L1B2) type piezoelectric ultrasonic motor. A rectangular piezoelectric prism with two separate electrodes on one main surface and one uniform electrode on the other main surface was used as a vibrator of the motor. By applying two sinusoidal signals with a phase difference of 180 degrees, one to separate electrode and the other to the uniform electrode, a longitudinal mode was excited. Since the length and the thickness of the prism were selected with a certain aspect ratio, the generated longitudinal mode was disturbed by the second bending resonance mode in thickness direction where d33 coupling coefficient is effective. As a result, an oblique or a narrow elliptical motion with an angle to length and thickness directions on the friction element that is attached on one end surface was obtained. Due to the slim geometry of the vibrator, the motor can be scaled and operated with multiple of them in a parallel structure. The motor has a good controllability and a wide range of moving speed from 1.0 micrometer/s up to 1.0 m/s.

Interval model of the piezoelectric drive

Abstract: Piezoelectric drives are widely used as high precision actuators. The paper deals with the design of interval models for studying of piezoelectric drive's dynamic. Results of such studying can be used for the construction of a precise position control system for a piezoelectric drive. We propose to design an interval model by defining some intervals where piezoelectric motor nonlinearity and uncertainty exist. We show some benefits of the proposed approach for modeling of piezoelectric drive and approve them by given simulations' results.

Inertial linear piezoelectric motor

Abstract: The invention relates to an inertial linear piezoelectric motor. Comprises a bottom plate, a slider, a sliding rail, two mass blocks and a piezoelectric stack; The bottom plate is an elongated plate,one end of which is connected with a slider, and the other end of which is connected with a vertical structure part and a horizontal structure part through a flexure hinge. The vertical structure andthe horizontal structure are hollow rhombus structure with the same structure. The piezoelectric stack is arranged in the hollow rhombus structure of the vertical structure part; the piezoelectric stack is arranged in the hollow rhombus structure of the vertical structure part; The slider is fitted on the slide rail to realize linear sliding along the slide rail. When a harmonic signal of a firstorder frequency is inputted to the piezoelectric stack to produce a first order resonant mode, the whole inertial linear piezoelectric motor moves to the right, and when a harmonic signal of a secondorder frequency is inputted to the piezoelectric stack to produce a second order vibration mode, the whole inertial linear piezoelectric motor moves to the left; As that frequency of the harmonic signal apply to the piezoelectric stack is changed, different vibration mode of the motor can be generated and the movement direction of the motor can be changed.

Electromechanical characteristic testing system for linear piezoelectric motor

Abstract: The invention discloses an electromechanical characteristic testing system for a linear piezoelectric motor. The electromechanical characteristic testing system comprises a moving platform component,a motor bracket component, a force sensing component, a displacement detecting component and a limiting component. The electromechanical characteristic testing system can measure mechanical characteristics and transient characteristics of the linear piezoelectric motor in two directions. By the replacement of a tray, a friction strip fixing block, a friction strip and a compression spring, the measurement of different linear piezoelectric motors can be achieved, which has good universality; and the electromechanical characteristic testing system has the advantages of being high in test precision, wide in measurement range and simple and convenient to operate and has broad application prospects.

Design issues of the piezo motor for the spacecraft reflector control system

Abstract: Creation of large-size reflectors for spacecrafts is a topical issue for the space industry. The accuracy of the reflecting surface form and the structure weight are the main criteria for the reflector design. The accuracy of the reflecting surface form during a long-term operation is provided by adjustment when using piezoelectric motors in the reflector design. These motors have small weight-size parameters and can reach great torque values. The piezo motor is a distributed mechanical-acoustic oscillation system. Mechanical-acoustic oscillations are generated in the piezo motor by a PZT-stack and transmitted to an oscillator element, and then from the oscillator element to a load action element. At high frequencies, when dimensions of the oscillator are proportionate to the wavelength, the energy is transmitted by means of acoustic waves. In this case, mechanical waves practically are not involved in the energy transmission process. This thesis shows a method for selecting the material of a mechanical-acoustic oscillation system according to the efficiency of the acoustic energy transmission via a piezoelectric layered structure.

Piezoelectric actuator, piezoelectric motor, robot, electronic component conveyance apparatus, printer, and manufacturing method of piezoelectric actuator

Abstract: A piezoelectric actuator includes a vibrator having a vibrating part including a piezoelectric element and a transmitting portion provided in the vibrating part and transmitting drive power to a driven part, and an energizing part that may energize the vibrator toward the driven part, wherein the energizing part has a base portion connected to the vibrator and a pair of spring portions integrally formed with the base portion.

Vibrator, piezoelectric actuator, piezoelectric motor, robot, electronic component conveyance apparatus, and manufacturing method of vibrator

Abstract: A vibrator includes a vibrating part including a pair of vibrating plates and a piezoelectric material provided between the pair of vibrating plates, a supporting part including a pair of supporting plates and an interplate portion provided between the pair of supporting plates, and a wire provided in the vibrating part and the supporting part, wherein the wire is exposed from the supporting part.

Driving device, piezoelectric motor, robot, electronic-component conveying device, and printer

Abstract: A driving device includes a plurality of vibrating bodies including transmitting sections configured to transmit vibration to a driven section and a control section configured to change vibration tracks of the transmitting sections of at least a pair of the vibrating bodies independently from one another. When a direction in which the driven section and the vibrating bodies are arranged is represented as a first direction and a direction orthogonal to the first direction is represented as a second direction, at least the two vibrating bodies have a plurality of vibration modes in which amplitudes in at least one of the first direction and the second direction of the transmitting sections are different, and the control section drives the at least two vibrating bodies in any one vibration mode among the plurality of vibration modes.

Piezo-electric motor for bowed rotor mitigation

Abstract: A piezoelectric motor comprising one or more concentric stator rings arranged to transfer energy and provide torque to an engine rotor or to an engine transmission. Such a piezo-electric motor improves spatial integration of an engine turning motor in a gas turbine engine.

Oscillator, piezoelectric actuator, piezoelectric motor, robot, electronic component transfer device, and printer

Abstract: PROBLEM TO BE SOLVED: To provide an oscillator with superior bonding strength, a piezoelectric actuator having the oscillator, a piezoelectric motor, a robot, an electronic component transfer device, and a printer.SOLUTION: An oscillator has a base part, a piezoelectric element with an electrode, an adhesive arranged between the base part and the electrode which the piezoelectric element has and bonding the base part and the piezoelectric element, and a terminal part electrically connected to the electrode which the piezoelectric element has. The electrode which the piezoelectric element has is provided with a part not including gold on a joint surface with the adhesive, while a surface of the terminal part is provided with a part including gold.SELECTED DRAWING: Figure 1

Optical zoom lens device

Abstract: The utility model discloses an optical zoom lens device, including solid fixed cylinder, solid fixed cylinder in be provided with the motion subassembly that can do the back and forth movement in solid fixed cylinder and be used for drive motion subassembly to be the drive assembly of back and forth movement, drive assembly is including passing the lead screw and the drive lead screw pivoted piezoelectric motor of motion subassembly, gu still be provided with the position detecting device who is used for inspection mirror head motion position in the fixed cylinder, position detecting device isincluding setting up magnetism resistive sensor and the relative position sensing magnetic sheet that sets up with magnetism resistive sensor on the motion subassembly. The utility model discloses apiezoelectric motor's driving method and the cooperation of magnetism resistive sensor position sensing mode, through closed loop control system, the control accuracy of improvement camera lens and the speed of motor can realize that the precision is detected to the position below the 1um.

Piezoelectric driving device, piezoelectric motor, robot, electronic component conveying device, printer, and method of manufacturing piezoelectric driving device

Abstract: PROBLEM TO BE SOLVED: To provide a piezoelectric driving device capable of exhibiting a large driving force, a piezoelectric motor, a robot, an electronic component conveying device, a printer, and a method of manufacturing the piezoelectric driving device.SOLUTION: The piezoelectric driving device includes a piezoelectric element having a piezoelectric body and an electrode arranged on the piezoelectric body. The piezoelectric driving device has a vibrating portion which vibrates in a second direction orthogonal to a first direction which is a direction in which the piezoelectric body and the electrode are arranged. When a length of a vibrating portion in the first direction is denoted as L1 and a length of the vibrating portion in the second direction is denoted as L2, L1/L2 is in a range of 1/5 or more and 10/7 or less.SELECTED DRAWING: Figure 2