Abstract: A wireless monitoring unit performs condition monitoring associated with a test point location of a host machine. The unit includes a high performance vibration sensor useful for monitoring the host machine for fault conditions and the like. The unit includes a second vibration sensor that has poorer metrological performance, but draws a comparatively insignificant amount of power from the battery. The second sensor takes a vibration measure periodically, which measure is processed to evaluate whether the machine is in a state eligible to undergo a health assessment. Diagnostic monitoring using the high performance vibration sensor is enabled only when the host machine it is in the eligible state. A low power temperature sensor provides additional data for guarding against a false trigger, in effect allowing the processor to distinguish against vibration from another machine propagating to the host machine causing the host machine to vibrate while the host machine is not running.

Abstract: Automatic fault diagnosis is performed on vibration data sensed from a machine. A set of faults to screen for is identified from the machine configuration. For each fault there are characteristic symptoms. For each characteristic symptom, there is a corresponding indication used to diagnose the symptom. The indications are based on analyses of the current vibration data. The diagnosed symptoms have weights assigned according to a Bayesian network, and are used to derive a Bayesian probability for the fault. A fault having a Bayesian probability exceeding a threshold value is identified as being present in the machine. For each fault a confidence level is derived. The confidence level for a first fault is based on a similarity between characteristic symptoms for the first fault and characteristic symptoms for each one of the other faults being screened.

Abstract: A wireless monitoring unit performs condition monitoring associated with a test point location of a host machine. The unit includes a high performance vibration sensor useful for monitoring the host machine for fault conditions and the like. The unit includes a second vibration sensor that has poorer metrological performance, but draws a comparatively insignificant amount of power from the battery. The second sensor takes a vibration measure periodically, which measure is processed to evaluate whether the machine is in a state eligible to undergo a health assessment. Diagnostic monitoring using the high performance vibration sensor is enabled only when the host machine it is in the eligible state. A low power temperature sensor provides additional data for guarding against a false trigger, in effect allowing the processor to distinguish against vibration from another machine propagating to the host machine causing the host machine to vibrate while the host machine is not running.

Abstract: A sensor unit is configured as a single body, removably mounted in its entirety to a test point location on a machine so machine vibrations propagate into the single body. Within are an accelerometer, circuit board, wireless interface, signal processor, and battery. The sensor unit transmits sensor data wirelessly in real time to a data collection unit. A technician with data collection unit in hand goes from machine to machine, along a route of multiple test point locations on multiple machines, mounting and dismounting the sensor unit and collecting machine vibration data. The sensor unit is configured to reduce frequency response impacts of the mass and volume of the circuit board, wireless interface, signal processor, and battery on dynamic behavior of the sensor unit with respect to machine vibrations to achieve a frequency response rating comparable to a wired sensor.

Abstract: Data acquisition and automatic diagnosis is performed at test points by respective wireless monitoring units (WMU). Each WMU tests a first indicator periodically at a first rate to determine whether to test a full set of indicators. Evolution of the first indicator determines the pass/fail result of a reduced assessment of the corresponding test point. The pass/fail result is automatically sent off-site to a central database. When a fail occurs, a full assessment is performed, which includes monitoring the full set of indicators. Automatic diagnosis is performed based on the full set of indicators. The reduced assessment does not include automatic diagnosis of a test point, but is used to decide whether to perform the full assessment and automatic diagnosis. Results of the automatic diagnosis are sent to the central database. Raw data is not sent automatically.

Abstract: A device for assembling together at a determined orientation a sensor (3) with a thread (6) and a support (2) having a tapped hole (12), the device including a first threaded portion (9) adapted to co-operate with the thread (6) of the sensor and a second threaded portion (11), of pitch different from the pitch of the first threaded portion, and suitable for co-operating with the tapped hole (12) of the support. The device also includes a washer (14) presenting on one side a bearing face (15) for bearing against the sensor, and on its other side, a contact face (16) for contacting the support, the washer (14) being provided with a through bore (25) for mounting the assembly element, the washer and the element being mounted together by an assembly system (30) connecting them together in rotation about the longitudinal axis, while leaving them free to move in translation.

Abstract: Automatic fault diagnosis is performed on vibration data sensed from a machine. A set of faults to screen for is identified from the machine configuration. For each fault there are characteristic symptoms. For each characteristic symptom, there is a corresponding indication used to diagnose the symptom. The indications are based on analyses of the current vibration data. The diagnosed symptoms have weights assigned according to a Bayesian network, and are used to derive a Bayesian probability for the fault. A fault having a Bayesian probability exceeding a threshold value is identified as being present in the machine. For each fault a confidence level is derived. The confidence level for a first fault is based on a similarity between characteristic symptoms for the first fault and characteristic symptoms for each one of the other faults being screened.

Abstract: A sensor unit is configured as a single body, removably mounted in its entirety to a test point location on a machine so machine vibrations propagate into the single body. Within are an accelerometer, circuit board, wireless interface, signal processor, and battery. The sensor unit transmits sensor data wirelessly in real time to a data collection unit. A technician with data collection unit in hand goes from machine to machine, along a route of multiple test point locations on multiple machines, mounting and dismounting the sensor unit and collecting machine vibration data. The sensor unit is configured to reduce frequency response impacts of the mass and volume of the circuit board, wireless interface, signal processor, and battery on dynamic behavior of the sensor unit with respect to machine vibrations to achieve a frequency response rating comparable to a wired sensor.

Abstract: An acoustic sensor for measuring the linear movement of an internal structure of a nuclear reactor using sound waves, including: an electro-acoustic transducer capable of emitting sound waves; and a waveguide capable of guiding the sound waves emitted by the transducer toward a measurement area of the internal structure, wherein the waveguide is capable of guiding the reflected wave and the waveguide is secured to the measurement area and arranged so as to be capable of extending or retracting in accordance with the movement of the internal structure of the nuclear reactor.

Abstract: The invention relates to a device for measuring at least the pressure of a fluid present in a chamber (16), comprising a sensitive element (36) arranged in a housing (38), supported by a joint (10) inserted between two elements (12, 14) which form said chamber. According to the invention, the housing (38) is open in the direction of the chamber (16) and the sensitive element (36) is enclosed in a material (67) filling said housing.

Abstract: The invention relates to a device for measuring at least the pressure of a fluid present in a chamber (16), comprising a sensitive element (36) arranged in a housing (38), supported by a joint (10) inserted between two elements (12, 14) which form said chamber. According to the invention, the housing (38) is open in the direction of the chamber (16) and the sensitive element (36) is enclosed in a material (67) filling said housing.

Abstract: A piezoelectric rotating motor includes a plurality of piezoelectric elements, a disk-shaped stator having a center portion in which the piezoelectric elements are accommodated, a circular friction zone which is formed on an outer peripheral portion of its one surface and a connecting portion which connects the center portion with the friction zone so as to form a lever transmitting and amplifying the axial strain of the piezoelectric elements to the portion of the friction zone located in the same angular sector as the piezoelectric elements and which has a cone shape at rear side of the friction zone so as to thin its thickness from the center portion to the outer peripheral portion and producing a progressive wave forming an elliptical vibration on the friction zone by the composition of its three dimensional strain due to the piezoelective effect of the piezoelectric elements and a rotor being contracted with the friction zone under pressure.

Abstract: A distribution network of electric signals in a piezoelectric or ultrasonic waves motor, is produced by depositing electrodes of conductive material on one face of a strip in dielectric material, that on the other face of the strip conductive tracks are deposited according to an interconnection diagram, designed beforehand to supply the piezoelectric elements with proper voltage. Drillings are made through the strip between the conductive tracks and the electrodes, and through plating or deposit of conducting material, these drillings are made conductive.