A vibration-sensor-integrated vibration exciter 4 has a chassis 21, an excitation unit 22, a magnet 23, a yoke 24, a vibration sensor 25, a fixed plate 26, a moving plate 27, coil springs 28a to 28d, a retaining plate 29, and a crisscross plate 30. Shafts 31a to 31d are fixed to the fixed plate 26. The excitation unit 22 is fixed to the crisscross plate 30. Four vibration-proof rubber members 32a to 32d are installed to the crisscross plate 30 at 90-degree pitches with same radius centering on the excitation axis of the fixed excitation unit 22. The crisscross plate 30 is installed to the retaining plate 29 through the vibration-proof rubber members 32a to 32d. A vibration applied to the chassis 21 is absorbed by the vibration-proof rubber members 32a to 32d, to prevent the yoke 24 from being dislocated in lateral direction due to the vibration.

Example implementations relate to receiving vibration notifications from vibration sensors. In example implementations, a subset of a plurality of vibration sensors from which vibration notifications are expected may be identified based on a position of a train along a track. The plurality of vibration sensors may be arranged in a predetermined order on the track. Whether vibration notifications have not been received from consecutive, with respect to the predetermined order, vibration sensors in the subset may be determined.

Example implementations relate to receiving vibration notifications from vibration sensors. In example implementations, a subset of a plurality of vibration sensors from which vibration notifications are expected may be identified based on a position of a train along a track. The plurality of vibration sensors may be arranged in a predetermined order on the track. Whether vibration notifications have not been received from consecutive, with respect to the predetermined order, vibration sensors in the subset may be determined.

A position sensor comprises a waveguide of magnetostrictive material which extends along a measurement path and which is configured for conducting mechanical pulses triggered by magnetostriction. A transducer at a first end of the waveguide serves for coupling a current pulse into the waveguide and for detecting a mechanical pulse conducted by the waveguide in the direction of the transducer. A damping element of an elastomer material is provided at a second end of the waveguide for damping a mechanical pulse propagating in the direction of the second end, wherein the hardness of the elastomer material increases as the distance from the transducer increases. The invention furthermore relates to a method of manufacturing a damping element of such a position sensor.

Disclosed is a method for detecting a value which represents the temperature of a vibrating element of an ultrasonic transducer. The ultrasonic transducer has a resonant frequency (f.sub.r). The method comprises the steps of operating the ultrasonic transducer with an electric measuring signal at a measuring frequency (f.sub.m) which is above the resonant frequency, and of detecting the absolute value of the complex impedance of the ultrasonic transducer at this measuring frequency (f.sub.m) and, building thereon, ascertaining the desired value, which is to represent the temperature of a vibrating element of an ultrasonic transducer, as a function of the detected absolute value of the complex impedance of the ultrasonic transducer at this measuring frequency (f.sub.m).

A solids detector may include a receptor configured to extend at least partially into a flow path of a fluid through a conduit. Further, the solids detector may include a sensor configured to receive an acoustic wave generated due to one or more solid particles in the fluid impacting the receptor. Additionally, the sensor may be configured to generate an electrical signal based on the acoustic wave. The electrical signal may be indicative of one or more impact energies of the one or more solid particles that impacted the receptor.

A position sensor comprises a waveguide of magnetostrictive material which extends along a measurement path and which is configured for conducting mechanical pulses triggered by magnetostriction. A transducer at a first end of the waveguide serves for coupling a current pulse into the waveguide and for detecting a mechanical pulse conducted by the waveguide in the direction of the transducer. A damping element of an elastomer material is provided at a second end of the waveguide for damping a mechanical pulse propagating in the direction of the second end, wherein the hardness of the elastomer material increases as the distance from the transducer increases. The invention furthermore relates to a method of manufacturing a damping element of such a position sensor.

A vibration-sensor-integrated vibration exciter 4 has a chassis 21, an excitation unit 22, a magnet 23, a yoke 24, a vibration sensor 25, a fixed plate 26, a moving plate 27, coil springs 28a to 28d, a retaining plate 29, and a crisscross plate 30. Shafts 31a to 31d are fixed to the fixed plate 26. The excitation unit 22 is fixed to the crisscross plate 30. Four vibration-proof rubber members 32a to 32d are installed to the crisscross plate 30 at 90-degree pitches with same radius centering on the excitation axis of the fixed excitation unit 22. The crisscross plate 30 is installed to the retaining plate 29 through the vibration-proof rubber members 32a to 32d. A vibration applied to the chassis 21 is absorbed by the vibration-proof rubber members 32a to 32d, to prevent the yoke 24 from being dislocated in lateral direction due to the vibration.

A vibration-sensor-integrated vibration exciter 4 has a chassis 21, an excitation unit 22, a magnet 23, a yoke 24, a vibration sensor 25, a fixed plate 26, a moving plate 27, coil springs 28a to 28d, a retaining plate 29, and a crisscross plate 30. Shafts 31a to 31d are fixed to the fixed plate 26. The excitation unit 22 is fixed to the crisscross plate 30. Four vibration-proof rubber members 32a to 32d are installed to the crisscross plate 30 at 90-degree pitches with same radius centering on the excitation axis of the fixed excitation unit 22. The crisscross plate 30 is installed to the retaining plate 29 through the vibration-proof rubber members 32a to 32d. A vibration applied to the chassis 21 is absorbed by the vibration-proof rubber members 32a to 32d, to prevent the yoke 24 from being dislocated in lateral direction due to the vibration.

A device to detect a rotational run speed of a piece of rotating machinery. The device includes a processor in communication with a magnetic flux sensor, a vibration sensor, and a memory which includes instructions. The processor is configured to receive magnetic flux data and apply a fast Fourier transform to the magnetic flux data to generate transformed magnetic flux data. The processor is configured to determine a prominent fundamental frequency in the transformed magnetic flux data. For an electrical machine, this prominent fundamental frequency corresponds to the synchronous speed or the speed of the stator magnetic field. The processor is configured to receive vibration data and apply a fast Fourier transform to the vibration data to generate transformed vibration data. The processor is configured to determine an isolated frequency focal band based on the prominent fundamental frequency in the transformed magnetic flux data and to determine the rotational run speed of the piece of rotating machinery based on the isolated frequency focal band and the transformed vibration data. By defining a relatively limited frequency band in which only the vibrational peak corresponding to the true rotational speed of the rotor will be located, it can be avoided to erroneously determine the speed based on a harmonic having a large amplitude.