A physical quantity detecting device includes a vibrating element and a charge amplifier. The vibrating element includes a first detection electrode, a second detection electrode, a third detection electrode, and a fourth detection electrode. The first and fourth detection electrodes have the same electrical polarity, the second and third detection electrodes have the same electrical polarity, and the first and second detection electrodes have opposite electrical polarities. The first and fourth detection electrodes are connected to the charge amplifier, and the second and third detection electrodes are connected to the charge amplifier.

A piezoelectric element device includes: a substrate including a plurality of vibrating portions having a first vibrating portion and a second vibrating portion; a piezoelectric element group in which a plurality of piezoelectric elements having a first piezoelectric element and a second piezoelectric element provided in the plurality of vibrating portions are coupled in parallel to each other; a plurality of load detectors having a first load detector including the first vibrating portion and the first piezoelectric element provided in the first vibrating portion and a second load detector including the second vibrating portion and the second piezoelectric element provided in the second vibrating portion; and a resin layer covering the piezoelectric element group. The first load detector resonates at a first resonance frequency, the second load detector resonates at a second resonance frequency, the first resonance frequency and the second resonance frequency are different from each other, the first resonance frequency changes in accordance with a load applied to the first load detectors via the resin layer, the second resonance frequency changes in accordance with a load applied to the second load detectors via the resin layer, and a first resonance frequency change range, which are changeable range of the first resonance frequency, and a second resonance frequency change range, which are changeable range of the second resonance frequency, do not overlap each other.

An wheel fastening inspection method includes: directly or indirectly applying vibration to a turbine shaft to be inserted to a bearing housing, the turbine shaft being provided with wheels at both ends protruding from the bearing housing, at least one of the wheels being fastened by a fastening member, and a rotary member being fastened by a fastening force generated by the fastening member to the turbine shaft to be integrally rotated with the wheel; measuring the vibration of the turbine shaft; and determining whether or not a vibration frequency at which a peak of the measured vibration of the turbine shaft is given is included in a setting range previously set.

A physical quantity detecting device includes a vibrating element and a charge amplifier. The vibrating element includes a first detection electrode, a second detection electrode, a third detection electrode, and a fourth detection electrode. The first and fourth detection electrodes have the same electrical polarity, the second and third detection electrodes have the same electrical polarity, and the first and second detection electrodes have opposite electrical polarities. The first and fourth detection electrodes are connected to the charge amplifier, and the second and third detection electrodes are connected to the charge amplifier.

A device (10) for monitoring strain of an elongate member (12) is deployed underwater. The device (10) comprises a first clamp (14) configured to embrace and couple to the elongate member (12) at a first axial location, a second clamp (16) configured to embrace and couple to the elongate member at a second axial location separated from the first axial location, and a sensor which is responsive to an angle between the first clamp and the second clamp.

A vibrator includes a vibrator element and a base on which the vibrator element is installed. In addition, when n is set to a natural number equal to or greater than 2, and j is set to a natural number equal to or greater than 1 and equal to or less than n, the vibrator element includes n inherent vibration modes having resonance frequencies different from each other, and when a resonance frequency of a main vibration of the vibrator element in the n inherent vibration modes is set to .sub.1 in a relationship between an arbitrary integer k.sub.j and a resonance frequency .sub.j corresponding to each of the n inherent vibration modes, the following three expressions are all satisfied. $\left(\frac{{.Math.}_{j=2}^n{k}_j{}_j}{-k_1}-{}_1\right)/{}_1$$.Math.{}_1.Math.0.13\underset{j=1}{\overset{n}{.Math.}}.Math.k_j.Math.10$

A resonator element includes a resonator blank having a base portion, a vibrating arm, a linking portion, and a connecting portion connects the base portion and the linking portion to each other, in which, when a thickness of the resonator blank is set to T, a width of the base portion is set to W1, and a width of the connecting portion is set to W2, a relationship of 50 mT210 m is satisfied, and a relationship of 0.067W2/W10.335 is satisfied, and in which, when a width of the arm section of the vibrating arm is set to W3, and a width of the hammer head is set to W4, a relationship of W42.8W3 is satisfied.

An environmental condition may be measured with a sensor (10) including a wire (20) having an ultrasonic signal transmission characteristic that varies in response to the environmental condition by sensing ultrasonic energy propagated through the wire using multiple types of propagation, and separating an effect of temperature on the wire from an effect of strain on the wire using the sensed ultrasonic energy propagated through the wire using the multiple types of propagation. A positive feedback loop may be used to excite the wire such that strain in the wire is based upon a sensed resonant frequency, while a square wave with a controlled duty cycle may be used to excite the wire at multiple excitation frequencies. A phase matched cone (200, 210) may be used to couple ultrasonic energy between a waveguide wire (202, 212) and a transducer (204, 214).

A vibration control component, comprising at least one bearing element, one spring element and one sensor device, wherein the sensor device comprises at least one sensor and at least one control unit and wherein the sensor device is formed to detect relative movements of the spring element and/or the bearing element.

An intensity measuring device according to one aspect is connected to a sensor device that outputs a signal waveform related to an elastic wave generated by shot processing, and measures an intensity of the shot processing based on the signal waveform. The intensity measuring device includes a waveform acquisition unit configured to acquire the signal waveform from the sensor device; a time-series data generation unit configured to generate time-series data of an effective value of the signal waveform; an average value acquisition unit configured to obtain an average value of the effective values for a predetermined time length based on the time-series data; and an intensity acquisition unit configured to obtain the intensity of the shot processing based on the average value of the effective values.