A method for transmitting data from an actuator to a control unit controlling the actuator. The control unit controls a piezoelectric element contained in the actuator. In order to transmit the data, in the actuator, a load being or not being connected in parallel with the piezoelectric element.

Disclosed is a method and device for electrically activating an electromechanical element (8) for positioning an element to be driven which is in contact at least intermittently with the electromechanical element (8). By temporal sequence or by the successive execution of a static friction phase and a slip phase, the element to be driven performs a discrete drive step in a first drive direction, while by temporal sequence or successive execution of a slip phase and a static friction phase the element to be driven performs a discrete drive step in a second drive direction which is oriented contrary to the first drive direction. By appropriate repetition, a plurality of discrete drive steps and thus a large travel can be realized, which is limited in principle only by the extent or length of the element to be driven.

An ultrasonic piezoelectric motor includes a frame, a carrier, and a Z-direction piezoelectric driver. The carrier is disposed on an inner side of the frame and moveable in a Z direction relative to the frame, the carrier is configured to receive a camera lens, and the Z direction is parallel to an optical axis of the camera lens. A Z-direction piezoelectric driver is located between the frame and the carrier. The ultrasonic piezoelectric motor periodically abuts against the carrier using the Z-direction piezoelectric driver and drives the carrier to move in the Z direction to focus a camera module.

An object of the present technique is to provide a drive circuit, an electronic device, and a method of controlling a drive circuit that can reduce power consumption. The drive circuit includes: a control circuit that controls application of an AC voltage to a capacitive load; an inductive element which constitutes a closed circuit along with the capacitive load; a diode, which is connected in series to the inductive element between the capacitive load and the inductive element so as to constitute the closed circuit; and a switch element, which is connected in series to the diode between the capacitive load and the inductive element so as to constitute the closed circuit.

A motion control system and method for controlling a stick-slip piezo motor includes an electronic controller and an analog driver for moving a mechanical device. When operating in a digital circuit mode, an electronic controller controls a digital-to-analog converter for moving the stick-slip piezo motor at a low speed. When operating in a faster analog circuit mode, the electronic controller, via an analog driver, operates to control an analog hardware circuit to move the stick-slip piezo motor at a high speed. The electronic controller operates in the digital circuit mode at start-up of the piezo motor.

A fluid jet dispenser using at least two multilayer piezoelectric actuators is provided. The fluid jet dispenser includes a dispensing head and an electrical driver. The dispensing head includes at least two d.sub.31-mode multilayer piezoelectric actuators, a displacement magnifying element mechanically coupled to the d31-mode multilayer piezoelectric actuators, a piston, and a nozzle. More preferably, the two d31-mode multilayer piezoelectric actuators operate in an anti-phase condition. The electrical driver is electrically coupled to the d31-mode multilayer piezoelectric actuators for displacing the actuators in directions substantially perpendicular to polarization of piezoelectric layers in the d31-mode multilayer piezoelectric actuators in response to charging and discharging of the actuators by the electrical driver, to generate a fast movement of the piston to jet a pressurized fluid out of the nozzle of the dispensing head.

A pre-loaded piezoelectric stack actuator comprising a stack of piezoelectric material. Caps are coupled at opposed ends of the stack. Each of the caps includes projecting fingers. Insulating plates are stacked between the ends of the stack and the caps. A pair of pre-loaded spring plates are coupled to the stack. The spring plates define slots. The fingers on the caps extend through respective ones of the slots at respective ends of the spring plates for coupling the spring plates to the stack. A method of pre-loading the piezoelectric stack actuator includes the step of mounting the stack, the caps, the insulating plates, and the spring plates in a pre-load tool that applies a pre-load tensile stretching force to the spring plates. The pre-load tensile force is subsequently released and the actuator is removed from the tool.

Systems, methods, and computer-readable media are disclosed for haptic feedback devices with reduced power consumption. In one embodiment, an example device may include a first spring, a mass coupled to the first spring, and a resonant piezoelectric actuator coupled to the first spring. The resonant piezoelectric actuator may be configured to impart a force on the mass via the first spring responsive to an applied voltage. The device may include a power source configured to supply the applied voltage to the resonant piezoelectric actuator, where motion of the mass generates vibration.

A driving control apparatus that controls driving of a vibration actuator having a plurality of electromechanical energy conversion elements. The driving control apparatus includes a controller configured to generate a plurality of driving signals each of which has a same waveform and has a different phase, and to respectively apply the plurality of driving signals to different elements of the plurality of electromechanical energy conversion elements. The controller changes the waveform according to the phase. A shape of a first waveform according to a first phase is closer to a square wave shape than a shape of a second waveform according to a second phase that is larger than the first phase.

The invention relates to a method for activating at least one portion, to be specific a change portion, of an electromechanical element (3), comprising the following steps: providing an electromechanical element, wherein at least the change portion has at least two electrodes, which are spaced apart from one another, and arranged between the electrodes a polycrystalline and ferroelectric or ferroelectric-piezoelectric material with a multiplicity of domains, wherein, in an initial state, at least some of the domains have directions of polarization that are different from one another; generating an electrical field between the electrodes of the change portion by applying an electrical voltage in the form of at least one voltage pulse with a defined amplitude and a defined duration; transforming some of the domains with directions of polarization that are different from one another into a state of the same direction of polarization as a result of the at least one voltage pulse, and thereby producing an increase in the extent of the electromechanical element along a direction of extent V that is defined and persists without the presence of an electrical voltage, or transforming some of the domains with the same direction of polarization into a state with directions of polarization that differ from one another as a result of the at least one voltage pulse, and thereby producing a decrease in the extent of the electromechanical element along the direction of extent V that is defined and persists without the presence of an electrical voltage. The invention also relates to the use of an electromechanical element activated by this method as an adjusting element and to the arrangement of an electromechanical element activated by this method between two elements (1, 2) that are to be moved with respect to one another.