A Rotary Traveling Wave Ultrasonic Motor With Four Groups of Nested PZT Ceramics: Design and Performance Evaluation.

This study proposes a rotary traveling wave ultrasonic motor utilizing the B (0, 5) axial bending mode of a ring-shaped stator. The proposed motor had a compact structure as only four groups of piezoelectric (PZT) ceramics were nested into the stator to produce a bending traveling wave, a new design method was proposed utilized less PZT ceramics to reduce the volume and to improve the mechanical output characteristics. The operating principle of the proposed motor was illustrated.

An experiment study on temperature characteristics of a linear ultrasonic motor using longitudinal transducers.

The temperature characteristics of a T-shaped linear ultrasonic motor using longitudinal vibration transducers are reported. When the ultrasonic motor is excited by different voltages, the surface temperatures at the driving foot, PZT ceramic and end cap are tested by a thermal imager for obtaining the thermal characteristics of the motor under no-load condition. PZT ceramic shows the maximum temperature increase.

A novel single-mode linear piezoelectric ultrasonic motor based on asymmetric structure.

A novel single-mode linear piezoelectric ultrasonic motor based on asymmetric structure is proposed. The motor adopts the combination of the first longitudinal vibration and the asymmetric mechanical structure to produce the oblique movement on the driving foot; then, the linear output motion is obtained under the friction coupling between the driving foot and the runner. The motor is designed and its operation principle is illustrated in detail.

A Four-Feet Walking-Type Rotary Piezoelectric Actuator with Minute Step Motion.

A four-feet walking-type rotary piezoelectric actuator with minute step motion was proposed. The proposed actuator used the rectangular motions of four driving feet to push the rotor step-by-step; this operating principle was different with the previous non-resonant actuators using direct-driving, inertial-driving, and inchworm-type mechanisms. The mechanism of the proposed actuator was discussed in detail.

Development of a bi-directional standing wave linear piezoelectric actuator with four driving feet.

A bi-directional standing wave linear piezoelectric ultrasonic actuator with four driving feet is proposed in this work. Two sandwich type transducers operated in longitudinal-bending hybrid modes are set parallelly. The working mode of the transducer is not simple hybrid vibrations of a longitudinal one and a bending one, but a special coupling vibration mode contained both longitudinal and bending components.

Influences of Excitation on Dynamic Characteristics of Piezoelectric Micro-Jets.

Piezoelectric micro-jets are based on piezoelectric ink-jet technology and can achieve the drop-on demand requirements. A piezoelectric micro-jet which is designed for bearing lubrication is presented in this paper. In order to analyze the fluid dynamic characteristics of the piezoelectric micro-jet so as to obtain good injection performance, a direct coupling simulation method is proposed in this paper.

A ring-type multi-DOF ultrasonic motor with four feet driving consistently.

A new type of multiple-degree-of-freedom (multi-DOF) ultrasonic motor was developed aiming at high output torque and compact structure. To reach this purpose, a ring type composite stator was proposed with four driving feet uniformly arranged in the inner circumference of the ring stator. The stator employs two orthogonal axial bending modes and a radial bending mode, by exciting two of them simultaneously, to generate elliptic trajectories on driving feet tips and to push sphere rotor around x, y and z axis respectively.

The design and experiment of a novel ultrasonic motor based on the combination of bending modes.

This paper presents a new-type linear ultrasonic motor which takes advantage of the combination of two orthogonal bending vibration modes. The proposed ultrasonic motor consists of eight pieces of PZT ceramic plates and a metal beam that includes two cone-shaped horns and a cylindrical driving foot. The finite element analyses were finished to verify the working principle of the proposed motor.

A cylindrical traveling wave ultrasonic motor using bonded-type composite beam.

A cylindrical traveling wave ultrasonic motor using bonded-type composite beam is proposed in this work. In this new design, a new exciting mode for L-B (longitudinal-bending) hybrid vibrations using bonded-type is adopted, which requires only two pieces of PZT ceramic plates and a single metal beam. In the new motor, the traveling wave of a cylinder can be excited by the L-B vibrations of a bonded-type beam.

A T-shape linear piezoelectric motor with single foot.

A new T-shape piezoelectric motor using the hybrid of two orthogonal longitudinal vibrations is proposed in this work. Six pieces of PZT ceramic plates are bonded on the upside and downside surfaces of a T-shape duralumin alloy base respectively to form the proposed motor. Elliptical movement can be generated on the driving tip by applying sine and cosine voltages to the PZT elements.

Ring-type traveling wave ultrasonic motor using a radial bending mode.

A traveling wave ultrasonic motor utilizing a radial bending mode of a thick ring is proposed. Twenty PZT stacks and 20 block springs are nested alternately into 40 slots cut in the ring's outer surface to produce a traveling wave. The prototype achieves maximum speed and torque of 146 r/min and 1.

A rectangle-type linear ultrasonic motor using longitudinal vibration transducers with four driving feet.

To make full use of the vibrational energy of a longitudinal transducer, a rectangle-type linear ultrasonic motor with four driving feet is proposed in this paper. This new motor consists of four longitudinal vibration transducers which are arranged in a rectangle and form an enclosed construction. Lead zirconate titanate ceramics are embedded into the middle of the transducer and fastened by a wedge-caulking mechanism.

A U-shaped linear ultrasonic motor using longitudinal vibration transducers with double feet.

A U-shaped linear ultrasonic motor using longitudinal vibration transducers with double feet was proposed in this paper. The proposed motor contains a horizontal transducer and two vertical transducers. The horizontal transducer includes two exponential shape horns located at the leading ends, and each vertical transducer contains one exponential shape horn.

A cylindrical traveling wave ultrasonic motor using a circumferential composite transducer.

This paper intends to present and verify a new idea for constructing traveling wave ultrasonic motors that may effectively avoid the drawbacks of conventional traveling wave motors using bonded PZT plates as the exciting elements. In the configuration of the motor's stator, a composite sandwich type transducer is used to excite a traveling wave in a cylinder with two cantilevers as the coupling bridges between the transducer and the cylinder. The design process of the stator is described using the FEM modal analysis method, and the establishment of traveling wave on the cylindrical stator was simulated by FEM transient analysis.

A cylindrical standing wave ultrasonic motor using bending vibration transducer.

A cylindrical standing wave ultrasonic motor using bending vibration transducer was proposed in this paper. The proposed stator contains a cylinder and a bending vibration transducer. The two combining sites between the cylinder and the transducer locate at the adjacent wave loops of bending vibration of the transducer and have a distance that equal to the half wave length of bending standing wave excited in the cylinder.

A rotary ultrasonic motor using bending vibration transducers.

A rotary ultrasonic motor using bending vibration transducers is proposed. In each transducer, two orthogonal bending vibrations are superimposed and an elliptical trajectory is generated at the driving foot. Typical output of the prototype is a no-load speed of 58 rpm and maximum torque of 9·5 Nm under an exciting voltage of 200 V(rms).

A high-power linear ultrasonic motor using longitudinal vibration transducers with single foot.

A high-power linear ultrasonic motor using longitudinal vibration transducers with single foot was proposed in this paper. The stator of proposed motor contains a horizontal transducer and a vertical transducer. Longitudinal vibrations are superimposed in the stator and generate an elliptical trajectory at the driving foot.

Actuating mechanism and design of a cylindrical traveling wave ultrasonic motor using cantilever type composite transducer.

Background: Ultrasonic motors (USM) are based on the concept of driving the rotor by a mechanical vibration excited on the stator via piezoelectric effect. USM exhibit merits such as simple structure, quick response, quiet operation, self-locking when power off, nonelectromagnetic radiation and higher position accuracy.

Principal Findings: A cylindrical type traveling wave ultrasonic motor using cantilever type composite transducer was proposed in this paper.

Control of an ultrasonic transducer to realize low speed driven.

This paper deals with the control of a transducer to realize low speed. A new PWM control is proposed to fit the transducer. By this control method, the transducer is directly excited by pulses whose width can be modulated.