A MEMS device includes a fixed portion fixed to a pedestal, a movable portion arranged inside the fixed portion and configured to be displaceable with respect to the fixed portion, a connecting portion that connects the fixed portion and the movable portion, a piezoelectric element disposed on at least one of the fixed portion or the connecting portion, and a detection portion that output a signal corresponding to a distortion of the movable portion. A voltage is applied to the piezoelectric element on the basis of the output signal of the detection portion thereby reducing the distortion transmitted from the fixed portion to the movable portion.

A vibration type motor (1) includes a vibrator (111) that includes a piezo element (111a), a contacting portion (111c), and a holding portion (111d), and generates a first vibration and a second vibration, a friction member (112) that makes frictional contact with the contacting portion of the vibrator, a holding member (113) that holds the holding portion of the vibrator, and a biasing member (114) that biases the holding portion of the vibrator to the holding member, and a condition of A3/A1<A4/A2 is satisfied where A1 and A2 are respectively amplitudes of the contacting portion in the first vibration and the second vibration, and A3 and A4 are respectively amplitudes of the holding portion in the first vibration and the second vibration in a state where the vibrator is not held by the holding member.

An ultrasonic motor, is disclosed having an ultrasonic actuator in the form of a rectangular piezo-electric plate, which has two generators for acoustic standing waves and on which at least two friction elements are arranged, an element to be driven, and an electric excitation device. The piezoelectric plate of the actuator is divided into two pairs of diagonally oppositely disposed sections by two virtual planes which extend perpendicularly to each other and which extend through the center line of the main surfaces of the actuator, wherein each of the generators includes two parts which can be operated in an antiphase manner and each of which is arranged in a diagonal section of the piezoelectric plate, and the friction elements are arranged on one or two end faces of the piezoelectric plate.

Provided is a method of manufacturing an oscillator, including: arranging an electrode on a piezoelectric ceramics free from being subjected to polarization treatment, to thereby provide a piezoelectric element; bonding the piezoelectric element and a diaphragm to each other at a temperature T1; bonding the piezoelectric element and a power supply member to each other at a temperature T2; and subjecting the piezoelectric ceramics to polarization treatment at a temperature T3, in which the temperature T1, the temperature T2, and the temperature T3 satisfy a relationship T1>T3 and a relationship T2>T3.

The invention relates to an electronic circuit (100) for controlling charging of a piezoelectric load (190). The electronic circuit comprises a charge pump (111) configured to supply a charging current to the piezoelectric load dependent on a charge control signal (131), a measurement circuit (113) configured to obtain a load voltage corresponding to a terminal voltage at a load terminal of the piezoelectric load, a comparator circuit (114) configured to compare an adjustable reference voltage with the load voltage. The electronic circuit is configured to determine the charge control signal dependent on the comparison so that the control signal controls delivery of the charging current dependent on the comparison. The electronic circuit is further configured to set the adjustable reference voltage to a target voltage (VT) and to set the adjustable reference voltage to a low limit voltage (Vlow), being lower than the target voltage, when the load voltage reaches the target voltage.

A vibration type driving apparatus includes a first vibrator including an electro-mechanical energy conversion element and configured to be in pressure contact with a driven member, a second vibrator including an electro-mechanical energy conversion element and configured to be in pressure contact with the driven member, and a first electric element connected in series with the second vibrator. The first vibrator is connected to a driving circuit, the second vibrator and the first electric element are connected in parallel with the first vibrator, the second vibrator is connected to the driving circuit via the first electric element, and a resonance frequency f of the first vibrator and a resonance frequency f2 of the second vibrator satisfy a relationship f1<f2.

A driving circuit for a vibration type actuator includes an inductor and a capacitor which are connected in series to an electric-mechanical energy conversion element, in which, in a case where a series resonance frequency based on the inductor and the capacitor is set as fs, and a resonance frequency in a vibration mode other than vibration used for driving of the vibrator is set as fu, 0.73.Math.fu<fs<1.2.Math.fu is satisfied.

A device for charging and discharging a capacitive actuator connectable to an output connection has a first capacitor disposed between an input connection and a reference potential. The device has a series connection composed of a first and a second power switching element which is connected in parallel with the first capacitor. The device additionally has a first coil with a first connection connected to the center tap of the series connection, wherein the second connection of the first coil is connected to the reference potential via a third power switching element and to the output connection via a fourth power switching element. Wherein the power switching elements have diodes connected in parallel therewith such that they are reverse-biased from the input connection or the output connection to the reference potential. Wherein a connection of the fourth power switching element is connected to the input connection via a diode.

A vibration type driving apparatus includes a first vibrator including an electro-mechanical energy conversion element and configured to be in pressure contact with a driven member, a second vibrator including an electro-mechanical energy conversion element and configured to be in pressure contact with the driven member, and a first electric element connected in series with the second vibrator. The first vibrator is connected to a driving circuit, the second vibrator and the first electric element are connected in parallel with the first vibrator, the second vibrator is connected to the driving circuit via the first electric element, and a resonance frequency f of the first vibrator and a resonance frequency f2 of the second vibrator satisfy a relationship f1<f2.

A driving circuit for a vibration type actuator includes an inductor and a capacitor which are connected in series to an electric-mechanical energy conversion element, in which, in a case where a series resonance frequency based on the inductor and the capacitor is set as fs, and a resonance frequency in a vibration mode other than vibration used for driving of the vibrator is set as fu, 0.73.Math.fu<fs<1.2.Math.fu is satisfied.