Abstract: An accelerometer (102) senses acceleration in a specific direction through the voltages produced by multiple piezoelectric sensors (114, 302, 304) electrically arranged in parallel in response to the acceleration. The main axes of sensitivity of the piezoelectric sensors are aligned and point in the same direction. The parallel arrangement enables to control the thermal noise level of the output signal of the accelerometer that originates in a bias resistor (116) connected in parallel to the parallel arrangement of the piezoelectric sensors.

Abstract: The present invention relates to a method of manufacturing a bearing component, in which a visually undetectable identification mark is created on a surface of the component by means of laser marking performed in a protective gas environment. The protective gas environment prevents the formation of a visible oxide layer, while the temperatures induced at the component surface and below the component surface, due to the laser marking, are sufficient to alter the microstructure of the bearing steel from which the component is made. The altered microstructure is revealable by applying an etchant to the visually undetectable mark, thereby allowing authentication of the bearing component.

Abstract: The present invention resides in a method of providing a mark on a surface of a metal component, where the mark comprises a symbol (301) representing a first entity of information and the method comprises a step of laser marking, in which a controllable laser beam is used to form the symbol (301) from two or more separate line segments (33 1-334), each line segment (33 1.334) having at least one point of overlap with another line segment. According to the invention, the method further comprises a step of embedding a second entity of information within the mark by modifying a sequence in which the two or more separate line segments (33 1-334) are formed.

Abstract: The present invention relates to a method of manufacturing a bearing component, in which a visible identification mark is created on a surface of the component using a laser beam. The laser marking creates an oxidised layer on the component surface and, in an underlying region, alters the microstructure of the bearing steel from which the component is made. According to the invention, the mark is then rendered visually undetectable with the naked eye, by removing at least the oxidised surface layer of the mark. This exposes the altered microstructure, which is revealable by applying an etchant to the visually undetectable mark.

Abstract: A combination of a bearing component and a sensor, wherein: (a) at least a portion of the bearing component is formed from a bearing steel; (b) the sensor comprises a sensor element and a support therefor; (c) at least a portion of the support is formed from a low carbon steel comprising no more than 0.2 wt. % carbon or from nickel or an alloy thereof or from titanium or an alloy thereof; and (d) the bearing component and the support are welded or brazed to one another via said respective portions.

Abstract: The present invention defines a strain sensor for measuring strains induced on a component surface (34). The strain sensor comprises a strain gauge (31) and a support member (32), whereby the support member is attached to the component surface only at first and second attachment places. The support member comprises a beam portion (39) that is adapted to bend in response to a relative displacement of the first and second attachment places, and the strain gauge is integrated on a surface (33) of this beam portion. To ensure a strong and stable bending response of the beam portion, the attached support member comprises at least one flexure hinge (45).

Abstract: The present invention defines a bearing unit comprising a bearing provided with one or more strain sensors, where the bearing comprises an inner ring and an outer ring, and where the one or more strain sensors (10) comprises a sensing element (14) integrated on a support member (12). According to the invention, the support member is a thin flat plate made of a metal material and is attached to a surface (5) of the bearing only by means of a first weld seam (21) and a second weld seam (22) located at first and second lateral ends of the support member. The present invention also defines a method of attaching the strain sensor (10) to the bearing surface (5).

Abstract: A device for attachment to a motor vehicle wheel includes an arrangement which, during movement or driving of the motor vehicle, detects vibrations which occur, evaluates the vibrations for an incipient fault state of a wheel bearing of the vehicle wheel, and delivers a signal when the monitoring or evaluation yields or indicates the incipient fault state.

Abstract: A combination of a bearing component and a sensor, wherein: (a) at least a portion of the bearing component is formed from a bearing steel; (b) the sensor comprises a sensor element and a support therefor; (c) at least a portion of the support is formed from a low carbon steel comprising no more than 0.2 wt. % carbon or from nickel or an alloy thereof or from titanium or an alloy thereof; and (d) the bearing component and the support are welded or brazed to one another via said respective portions.

Abstract: A device for attachment to a motor vehicle wheel includes an arrangement which, during movement or driving of the motor vehicle, detects vibrations which occur, evaluates the vibrations for an incipient fault state of a wheel bearing of the vehicle wheel, and delivers a signal when the monitoring or evaluation yields or indicates the incipient fault state.

Abstract: A device for attachment to a motor vehicle wheel includes an arrangement which, during movement or driving of the motor vehicle, detects vibrations which occur, evaluates the vibrations for an incipient fault state of a wheel bearing of the vehicle wheel, and delivers a signal when the monitoring or evaluation yields or indicates the incipient fault state.

Abstract: Method and sensor arrangement for determining a contact force vector acting on a rolling element hearing in operation. Sensor signals are received from a plurality of sensors measuring performance characteristics of the rolling element bearing. The received sensor signals are processed to determine the contact force vector. The plurality of sensors are arranged to measure a bearing component deformation, and the step of processing comprises the step of determining the contact force vector using an inverse transformation of a finite element analysis model which describes the rolling element bearing. The finite element analysis model is simplified using at least one generalized mode shape, the at least one generalized mode shape being a mathematical description of a natural mode deformation of a component of the rolling element bearing, such as the inner or outer ring.

Abstract: Method and sensor arrangement for determining a load vector acting on a rolling element bearing (1) in operation. A plurality of N sensors (8) are provided which measure displacement and/or strain for determining displacement and/or strain in one of the elements (5, 6, 7) of the rolling element bearing (1). Furthermore, a mode shape coefficients calculator (11) is provided, connected to the plurality of N sensors (8), for determining a deformation of the element (5, 6, 7) by calculating amplitude and phase of N/2 Fourier terms representing at least one radial mode shape of the ring shape element (5, 6, 7). Also, a bearing neural network (12) is present, connected to the mode shape coefficients calculator (11), the bearing neural network (12) being trained to provide the load vector on the rolling element bearing (1) from the N/2 Fourier terms.

Abstract: Disclosed is a rotational speed sensor comprising a rotatable ring. The rotational speed sensor has K magnetic pole pairs distributed angularly over the rotatable ring. Also, sensors are positioned relative to the rotatable ring such that a varying magnetic field is detected. The sensors comprise a first pair being positioned 2?L/K radians apart. The sensors further comprise a second pair being positioned 2?M/K radians apart. The first pair of sensors and second pair of sensors are positioned at a relative position of (2?/K)*((2n?1)/2 radians. L, M are integers between one and K and n is an integer greater than one.

Abstract: Sensor assembly for measuring a load on a bearing having at least one bearing ring (11), the at least one bearing being provided with a cavity (12) for holding the sensor assembly. The sensor assembly comprises a series mounting between opposing sides (17, 18) of the cavity (12), the series mounting comprising a piezoelectric plate (16) and a spring (19) with spring stiffness k. Alternatively, the sensor assembly further comprises a body (14) with mass in mounted between the piezoelectric plate (16) and the spring (13), to allow simultaneous load measurement and health monitoring.

Abstract: A method for analysing regularly recurring mechanical vibrations comprises the steps of plotting an amplitude/time spectrum associated with the vibrations, dividing the amplitude/time spectrum into time intervals shorter than the shortest time lapse between two consecutive excitations, subjecting those parts of the amplitude/time spectrum defined by each time interval to a Fourier transformation in order to obtain an amplitude/vibration-frequency interval spectrum associated with each time interval, and subjecting those amplitudes in each amplitude/vibration frequency interval spectrum associated with certain vibration frequencies to a Fourier transformation in order to obtain an excitation-frequency spectrum associated with the respective vibration frequency.