A control method for a piezoelectric motor having a vibrating portion including a piezoelectric element and a transmitting portion transmitting vibration of the vibrating portion to a driven member, and synthesizing longitudinal vibration and flexural vibration by energization of the piezoelectric element to vibrate the vibrating portion and elliptically move the transmitting portion and moving the driven member by the elliptical motion, includes changing an orbit of the elliptical motion according to a load received by the transmitting portion.

A crystal oscillator device is disclosed. The crystal oscillator device includes a crystal piece provided in a casing; a pair of excitation electrodes provided for the crystal piece; a coil provided on the crystal piece; a magnetic flux generating member configured to generate magnetic flux passing through the coil; and an alarm generator configured to generate an alarm based on a signal whose amplitude is equal to or less than a reference value, the signal being generated in the coil.

An apparatus includes a dielectric tile array including a plurality of dielectric tiles; and a plurality of electroactive (EA) material blocks configured to expand or contract in response to being actuated by the application of an actuation voltage.

There is provided a vibration generating device including: a housing having an internal space; a vibration member having one end fixedly attached to the housing; a piezoelectric element installed on the vibration member; and a mass body fixedly attached to the vibration member, wherein the vibration member includes an installation part on which the piezoelectric element is installed, and an extension part extended from at least one side surface of the installation part, and a maximum displacement portion of the vibration member is changed depending on a vibration mode.

The invention concerns an electronic device for controlling a converter from an input voltage to at least one output voltage, comprising a first bridge comprising two first switching branches, each between two terminals of the input voltage and comprising two first switches connected at a first midpoint; at least one second bridge comprising two second switching branches, each between two terminals of the output voltage and comprising two second switches connected at a second midpoint; at least one pair of first and second piezoelectric assemblies, each connected between respective first and second midpoints, distinct from one piezoelectric assembly to the other.

The control device commands, during a respective resonance cycle of the piezoelectric assemblies, a switching of each of the switches to alternate phases at substantially constant voltage across the piezoelectric assemblies and phases at substantially constant load across said piezoelectric assemblies.

It further commands, during each phase with a substantially constant load, into the closed position at the same time at most one respective switch among the switches directly connected to the first piezoelectric assembly and at most one respective switch among the switches directly connected to the second piezoelectric assembly, and into the open position all the other switches of the first and second switching branches.

A converter of an input voltage into at least one output voltage, including a pair of first and second piezoelectric assemblies; a first bridge including two first switching branches each having at least one first switch; a second bridge including two second switching branches each having at least one second switch; each piezoelectric assembly including a first end connected to the first bridge and a second end connected to the second bridge; each first switch being connected between a terminal of the input voltage and a first end; each second switch being connected between a terminal of the output voltage and a second end. It includes at least one complementary switch connected directly between the ends of a pair of piezoelectric assemblies, connected to a same bridge,

An elastic wave device includes a supporting substrate, a high-acoustic-velocity film stacked on the supporting substrate and in which an acoustic velocity of a bulk wave propagating therein is higher than an acoustic velocity of an elastic wave propagating in a piezoelectric film, a low-acoustic-velocity film stacked on the high-acoustic-velocity film and in which an acoustic velocity of a bulk wave propagating therein is lower than an acoustic velocity of a bulk wave propagating in the piezoelectric film, the piezoelectric film is stacked on the low-acoustic-velocity film, and an IDT electrode stacked on a surface of the piezoelectric film.

When frequencies used in the two-frequency measurement of a SAW sensor are represented by f.sub.1 and f.sub.2 (f.sub.2>f.sub.1), an electrical signal processing device is provided without use of oversampling at a frequency higher than twice the frequency f.sub.2 or a two-system low-frequency conversion circuit, in which temperature compensation with the same accuracy as the case where these are used can be realized. Narrow band frequency filtering is applied to a waveform after roundtrips in a delay line type SAW sensor capable of transmitting and receiving multiple frequencies, the two frequencies f.sub.1 and f.sub.2 (f.sub.2>f.sub.1) are extracted, and a delay time is determined utilizing an aliasing obtained by applying undersampling at a frequency lower than twice the frequency f.sub.1.

A transducer device, including an electroactive polymer transducer, which has at least two electrode layers which are situated in parallel to one another and which are connected to one another by inserting an elastic intermediate layer in each case, and including a circuit having electronic components for the purpose of generating an electrical voltage applied to the electrode layers of the polymer transducer, the circuit increasing an input voltage to a voltage which is increased with regard to the input voltage.

The inventive concept discloses a piezoelectric energy harvesting array and a method of manufacturing the same. The manufacturing method may include forming a plurality of piezoelectric energy harvesting devices; connecting masses to one side of the piezoelectric energy harvesting devices and connecting the other side of the piezoelectric energy harvesting devices facing the masses to a base; and individually tuning a resonant frequency of each of the piezoelectric energy harvesting devices to prevent mismatch of resonant frequency when the masses vibrate.