Abstract:
A method of measuring tension in a moving strand (11, 21, 31) comprising the steps of: causing the strand to pass along a working path (X, P1) between first (A) and second (B) locations: directing across the strand at a predetermined position (P, 8, 14) a jet of gas (Q; Q'; Q1, Q3, Q2, Q4; F) to displace the strand (11, 21, 31) from the working path (X, P1) to a displaced path (ADB, D', P2); measuring the lateral displacement (H, D) of the strand (11, 21, 31) from the working path (X, P1) to the displaced path (ADB, D', P2); using the value of lateral displacement (H, D) and the distances (I1, I2) of the predetermined points along the strand (11, 21, 31) to the first and to the second locations to establish the tension (F) in the strand: characterised in that the velocity of the jet of gas (Q; Q'; Q1, Q2, Q3, Q4; F) is periodically varied. Typically the velocity of the gas jet is varied either by varying the gas flow speed through a nozzle (13; 2, 3; 2, 5, 3, 6; 16) defining the direction of the jet or alternatively the velocity of the gas jet (F) can be varied by varying the radial direction of the gas jet (F) relative to a predetermined location (14) on the working path (P1). The invention is further directed to apparatus for carrying out the method and product achieved by use of the method or apparatus.
Abstract:
The device is used in knitting machines to control technological parameters of the knitting process. In a pistol-like casing (1) of the device are mounted a pick-up (4) for measuring the characteristics of the thread, a unit (7) for catching the thread and pressing it against the measuring pick-up (4), which is provided with thread guides (8) and is located in the front part of the casing (1), and an electronic unit for conversion of the signals of the pick-up (4). The front part of the casing (1) is shaped as a wedge (2) and is provided, on one of its sides, with a slot (3) for the thread. The thread guides (8) are mounted at the face-ends of the wedge (2) with the possibility of reciprocating movement along them and along a trajectory crossing the slot (3).
Abstract:
The invention relates to a method for detecting crack formation in a hoisting member, comprising the steps of measuring a stress under load at two points of the hoisting member, comparing the measured stresses and generating a warning signal when the measured stresses differ too much from each other. The invention also relates to a device for detecting crack formation in a hoisting member, comprising means arranged at two points of the hoisting member for measuring a stress under load, means connected to the measuring means for comparing the measured stresses, and means connected to the comparing means for generating a warning signal when the measured stresses differ too much from each other. Finally, the invention relates to a hoisting frame, comprising a number of hoisting members which are mounted thereon close to its corners, and crack detection devices connected thereto.
Abstract:
Method for monitoring the rigging (4) of a sailing vessel (1). The method comprises a step for measuring elongation, wherein the elongation of at least part of a stay (21) is measured. The invention furthermore relates to a stay (21) provided with elongation-measuring means (32), such as an optical fibre (32) for example, to a measuring device (10) comprising elongation-measuring means (32) which can be fastened to a stay (21), as well as to the use of the data which is obtained by the method for monitoring the rigging (4) of a sailing vessel (1).
Abstract:
A process for manufacturing an optical fibre comprises the steps of producing a glass core rod; measuring the refraction index profile in a plurality of sections of the core rod, for obtaining a corresponding plurality of refractive index profiles; processing the plurality of refractive index profiles for determining a drawing tension variation law; depositing glass soot onto the core rod to obtain a glass preform; consolidating the glass preform; and drawing the optical fibre from the glass preform by applying a drawing tension to the optical fibre, wherein drawing tension is varied in accordance to the drawing tension variation law.
Abstract:
System for monitoring high-tension cables (1) in air stretches as well as a use of the same. The system comprises at least one optic fibre (3) fastened to the high-tension cable (1), said optic fibre comprising at least one Bragg grating (4) with known reflection characteristics, a light source (6) for emitting light within a known range of wavelengths into the optic fibre, and measuring devices (7) for detection of light reflected from the Bragg gratings (4) in the fibre (3) and for recognizing light reflected from each Bragg grating (4) based on their known reflection characteristics.
Abstract:
An optical fiber monitoring method and apparatus is described for monitoring the signal loss within an optical fiber during installation of the optical fiber. The apparatus contains a jig for advancing the optical fiber along a predetermined path, a light source for transmitting light signals along the optical fiber, and a light sensor for detecting the light signals. The detected light signals are converted to an audible signal having a frequency which varies in relation to the detected signal. An audio transducer then outputs the audible signal. Since the frequency of the audio signal is a measure of the signal loss along the optical fiber and, therefore, is a measure of the amount by which the optical fiber is bent during the installation process, the audible signal can be monitored in an "eyes-free" manner to detect excessive bending of the optical fiber in order to prevent damage to the optical fiber during installation.
Abstract:
Verfahren und Einrichtung zur Überwachung eines Antriebsriemens Verfahren zur Überwachung eines Antriebsriemens (7) in einen Riementrieb einer Arbeitsmaschine, insbesondere in einem Riementrieb einer landwirtschaftlichen Arbeitsmaschine, bei demin einer der Arbeitsmaschine zugeordneten Aufzeichnungseinrichtung ein oder mehrere Sensoren, Prüfungs-oder Aufnahmeeinrichtungen vorgesehen sind, durch welche Messdaten ermittelt werden, die einen Betriebszustand der Arbeitsmaschine, des Riementriebs und/oder einen Betriebszustand oder physikalisch-geometrischen Zustand des Antriebsriemens innerhalb des Riementriebs repräsentieren, wobei die Daten mittels einer in der Aufzeichnungseinrichtung vorgesehenen Übertragungseinrichtung in eine von der Arbeitsmaschine entfernte Auswertungseinrichtung übertragen und dort gespeichert und/oder ausgewertet werden.