Abstract: An actuator includes a piezoelectric element, a vibration plate, a support, a holder, and first and second fixing portions. The vibration plate has the piezoelectric element joined thereto and bends and vibrates in accordance with expansion and contraction of the piezoelectric element. The support supports the vibration plate on a base to allow bending and vibration of the vibration plate. The holder holds an object of vibration to the vibration plate. The first fixing portion is coupled to the support and fixes the support to the base. The second fixing portion is coupled to the holder and fixes the object of vibration to the holder. The first and second fixing portions are each displaceable in a direction intersecting the direction of the expansion and contraction of the piezoelectric element.

Abstract: A device and method using the electromechanical properties of piezoelectric materials to generate and deliver electrical power to a high speed electrically powered rotatable shaft. The device has a stationary module that is connected to an electrical source; and has a rotatable module, which is mechanically connected to the electrically powered rotatable shaft. The rotatable module rotates relative to the stationary module. When the stationary module is electrically energized, the stationary piezoelectric component expands and causes the rotatable piezoelectric component to compress. When the rotatable piezoelectric component compresses, it generates electrical power transferred to the electrically powered rotatable shaft. Thus, electrical energy can be delivered to the electrically powered rotatable shaft without a direct electrical connection. The present invention is particularly useful in applications requiring large diameter through-hole dimensions.

Abstract: A piezo actuator comprises a piezo material having a first, top surface, a second, bottom surface, and a third, circumference surface. The piezo material has a polarity and the piezo material includes one or more mounting holes in the piezo material, the one or more mounting holes being positioned substantially central in at least the top surface or the bottom surface of the piezo material. The actuator also comprises at least one contact point for contacting a load to be actuated, the at least one contact point being positioned on the third, circumference, surface of the piezo material, and a set of electrodes being positioned on the top surface of the piezo material and at least one electrode being positioned at the bottom surface of the piezo material.

Abstract: A method is disclosed for closed-loop motion control of an ultrasonic motor having at least one actuator with an excitation electrode and at least one common electrode, an element to be driven, a controller and at least one electrical generator for generating at least first and second excitation voltages U1 and U2 to be applied to the electrodes of the actuator for vibration of the actuator. A friction element of the actuator, due to its vibration, intermittently contacts the element to be driven with a driving force. The method includes providing the at least two excitation voltages U1 and U2 with different resemblance frequencies, a frequency difference deviating from a servo sampling frequency of the controller by 5 kHz at the most, and simultaneously applying the excitation voltages to the electrodes of the actuator.

Abstract: A flyback converter includes a primary side circuit to receive an input voltage signal, a secondary side circuit to generate an output voltage signal using the input voltage signal, a synchronous rectifier switch, and a synchronous rectifier controller. The synchronous rectifier controller receives an attenuated drain-source voltage signal of the synchronous rectifier switch and the output voltage signal. The synchronous rectifier controller includes a threshold voltage generator to generate a first voltage signal using the output voltage signal, a first comparator to compare the attenuated drain-source voltage signal to the first voltage signal and, in response, generate a first comparison signal, and a second comparator to compare the attenuated drain-source voltage signal to a second voltage signal and, in response, generate a second comparison signal.

Abstract: 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.

Abstract: The present disclosure relates to an axial flux motor for a reaction wheel, and method of using and making the same. The motor includes a stator and a rotor. The stator comprises a printed circuit board (PCB) including a first motor coil. The rotor is coupled to a first ring-shaped magnet having an alternating pole arrangement. In a further embodiment, the rotor includes permanent magnets, and the stator PCB includes a first motor coil, and a first high thermal conductivity element.

Abstract: A three-degrees-of-freedom adjustment device driven by piezoelectric ceramics includes a Z-direction deflection mechanism at a bottom, an X-direction deflection mechanism mounted at the bottom, a Y-direction deflection mechanism mounted on the X-direction deflection mechanism, and a stage mounted on a deflect block of a deflection mechanism angle output; wherein the Z-direction deflection mechanism is located at the bottom, including a mounting substrate and two pre-compressed piezoelectric stacks; the piezoelectric stacks in the Z-direction deflection mechanism deflect in a Z direction under equal voltages; the X-direction deflection mechanism is similar to the Y-direction deflection mechanism in principle, including a deflection mechanism frame and a pair of piezoelectric stacks, wherein the X-direction deflection mechanism and the Y-direction deflection mechanism are vertically mounted, and are perpendicular to the Z-direction deflection mechanism plane as a whole.

Abstract: An electromechanical stator includes an actuator section, a support section and a spring section. A continuous sheet of elastic material constitutes at least a part of each of these sections. The actuator section includes a vibration body and a moved-body interaction portion. The vibration body includes an electromechanical volume. The spring section is elastic, with a spring constant, enabling provision of a normal force in the vibration direction upon displacement of the fixation point. Also an electromechanical motor and a method of operating such an electromechanical motor are disclosed.

Abstract: A vibration type actuator including vibrating elements and a contact element that is brought into contact with each other in a first direction. The vibration of the vibrating elements includes vibration in a first vibration mode in the first direction and vibration in a second vibration mode in a second direction intersecting the first direction. In the vibrating elements, a minimum value of a resonance frequency in the second vibration mode is greater than or equal to a maximum value of a resonance frequency in the first vibration mode, and a ratio of a difference between the maximum value and the minimum value of the resonance frequency in the second vibration mode to the minimum value of the resonance frequency in the second mode is less than or equal to a predetermined value.

Abstract: An actuator with a rectangular shape] is made of polarized electromechanical material having two large main surfaces and at least four side surfaces, two of which being longer than the other two side surfaces. At least one friction element is arranged on at least one of the shorter side surfaces. At least two active electrodes are arranged on one of the main surfaces, with one common electrode arranged on the other of the main surfaces The electromechanical material of the actuator is excitable to perform standing wave deformations due to an electric field generated therein for moving the friction element to drive an element. The actuator aspect ratio for its length to its thickness is between 3.9 and 4.1 and an aspect ratio for the length relative to width is between 2 and 5.

Abstract: A vibration wave motor includes a vibrator; a first holding member configured to hold the vibrator; a second holding member; an elastic coupling member configured to couple the first holding member and the second holding member to each other; a friction member; and a pressurizing unit, wherein the vibrator and the friction member relatively move due to vibration of the vibrator, wherein the elastic coupling member includes a first coupling portion and a second coupling portion, and wherein one of the first coupling portion and the second coupling portion is arranged on a straight line that is parallel to a direction of the relative movement and passes through a pressurizing gravity center and another of the first coupling portion and the second coupling portion is arranged on a straight line that is orthogonal to the direction of the relative movement and passes through the pressurizing gravity center.

Abstract: A door, in particular a high-speed industrial door, with an intelligent door leaf is disclosed. The door has a door leaf which is guided by lateral guides and covers a door opening, and which has a first and a second side, a driving means for moving the door leaf between an open and a closed position, a door control means for controlling the driving means, as well as an electrically self-sufficient door leaf means arranged in the door leaf. The door control means also has a first communication unit. In addition, the door leaf device comprises at least one sensor unit for detecting at least a physical quantity, an energy converter which converts non-electrical energy into electrical energy, a second communication unit and at least one actuator unit. The first and second communication units communicate wirelessly with each other.

Abstract: A flap actuator for adjusting the orientation of a flap or the like, the actuator. The actuator includes: a static arcuate member having a radius of curvature; a piezoelectric motor biased to be in operable contact with the static arcuate member; a housing for housing the piezoelectric motor; and a flap orientation shaft operably connecting between the housing and the flap. The distance between the shaft and the static arcuate member is essentially equal to the radius of curvature of the static arcuate member.

Abstract: In a vibration unit, a piezoelectric element enters an internal space of a through hole; and thereby, a second case member can be arranged proximate to a first case member. Therefore, a thickness of the vibration unit can be reduced, namely, a height of the vibration unit can be reduced. As described above, since the thickness of the vibration unit is reduced, a size of the vibration unit can be reduced.

Abstract: A vibration device that includes a flat plate that has a first main surface and a second main surface; a vibrator that is configured to vibrate along a first direction parallel to the first main surface; a connecting member that connects the vibrator to the first main surface of the flat plate; a support member having a cavity or a recess in a portion thereof facing the vibrator; and a cushioning material connecting the first main surface of the flat plate to the support member, the cushioning material being disposed so as to not overlap with the vibrator in a plan view of the vibration device. A combined length of the vibrator and the connecting member in a second direction perpendicular to the first main surface of the flat plate is larger than a length of the cushioning material in the second direction.

Abstract: A contact body that makes it possible to easily verify whether or not the resin has been properly impregnated in the pores. A metallic sintered body having a plurality of pores, as a main body, is in contact with a vibration element in a vibration actuator. The contact body includes a sliding portion that has a sliding surface in contact with the vibration element, and a non-sliding portion adjacent to the sliding portion and not in contact with the vibration element. The non-sliding portion is provided with a resin lump containing hard particles and resin, and the resin lump is formed to be lower in height in a vertical direction than the sliding surface. In the sliding portion, part of hard particles and resin is exposed on the sliding surface.

Abstract: A voltage converting apparatus includes a comparison circuit, a compensation signal generator, and a voltage converter. The comparison circuit generates a comparison result according to an output voltage, an input voltage, and a compensated feedback signal. The compensation signal generator provides a compensation signal held to be equal to a reference voltage at a first time interval in an enable period in a working cycle and sets the compensation signal to be a ramp signal at a second time interval in the enable period. The compensation signal generator generates the compensated feedback signal according to a feedback signal and the compensation signal. The voltage converter generates a control signal according to the comparison result, performs a voltage converting operation through an inductor according to the control signal, and generates the output voltage. The feedback signal is generated according to a current on the inductor.

Abstract: A converter circuitry between a first network, which may be either a poly-phase medium-voltage alternating current (AC) network, at least one polyphase low-voltage AC network or at least one direct-current (DC) network, and a second network, which may be either a polyphase medium-voltage AC network or a medium-voltage DC network, wherein the converter circuitry comprises at least one power bus and low-voltage power cells both at the first and at the second network side such that each power cell is connected to a power bus via a transformer. Each power bus is connected to a low-voltage power unit, which is able to supply pre-charging power via the power bus to all power cell intermediate DC-link filtering capacitors before the converter is started. The low-voltage power unit is also able to take care of a resistor braking in case the first network cannot take the power supplied by the load connected to the second network.

Abstract: A power conversion device includes a conversion circuit constituted of a plurality of arm circuits and a bypass circuit. The bypass circuit includes a full-wave rectification circuit, a positive-side connection arm, and a negative-side connection arm. The full-wave rectification circuit is connected between a plurality of AC connections, a positive-side intermediate node, and a negative-side intermediate node, and configured to convert AC voltages generated at the plurality of AC connections into a DC voltage across the positive-side intermediate node and the negative-side intermediate node and output the DC voltage. The positive-side connection arm blocks a current in a direction from a positive-side DC terminal toward the positive-side intermediate node. The negative-side connection arm is connected between the negative-side intermediate node and a negative-side DC terminal and blocks a current in a direction from the negative-side intermediate node toward a negative-side DC terminal.