Abstract: The present invention relates to a measuring transformer which contains a primary conductor which carries current to be measured, and a secondary coil which is magnetically coupled thereto. The primary conductor is shaped helically and forms a body, like a helical spring, which surrounds the secondary coil with at least one turn. The primary conductor is preferably formed by a tube having a spiral groove which passes through its wall. The primary conductor has inherent stability which is very high such that no special holding means are required for the secondary coil. The secondary coil is extremely easy to install in the primary conductor and there are no problems with installation tolerances and the like.

Abstract: A capacitive sensor has a pair of plate-shaped electrodes (4) spaced apart from one another and defining a measurement slot (3) therebetween. Guides (5) mask out edge zones of the measurement slot (3) and reduce its width. These guides (5) are formed as the two legs of an elongated U-shaped guiding part (7) which can be inserted into the measurement slot (3) and can be fixed in the latter.

Abstract: The surface of a yarn (G) is imaged on a sensor (7) having a plurality of sensor elements of differing structural arrangement. The signals of the individual sensor elements are compared with one another, and the structure of the examined yarn surface is determined on the basis of correspondence with the appropriate sensor element. The structure to be examined is formed both by the actual yarn surface and by the yarn edge, including projecting fibers and possible impurities, such as foreign fibers, included in the yarn.

Abstract: The system includes a control system for deriving control variables from parameters which influence the productivity of the spinning machine (RS). Besides parameters which are measured by sensors, for the purposes of the control consideration is also given to those parameters which are not measurable or measurable only with difficulty. The last-mentioned parameters are included in the control system by means of a fuzzy logic, for which purpose the control system exhibits a fuzzy controller (FC).

Abstract: A device for measuring the mass of fiber slivers contains an entry part for the fiber sliver to be measured and a measuring part adjoining the entry part. Arranged on the measuring part are two measuring members working on different measurement principles, specifically a so-called fiber-sliver mechanically, and so-called active-pneumatic measuring member for measuring the pneumatic pressure generated by the fiber sliver at a contraction. In addition to measuring the mass of fiber slivers, the device can be used for obtaining a characteristic variable for their composition or for separate regulation and monitoring in a control stage.

Abstract: Test material (F) such as a textile yarn is illuminated and the light reflected from the test material is measured so that the presence of a foreign substance can be determined from a change in the reflected light. When detecting foreign substances which are darker than the test material (F), an image of the test material in front of a light background (4) is projected onto a sensor (3), and for the detection of lighter foreign substances an image of the test material in front of a dark background is projected onto the sensor. The apparatus and method may be used in combination with an electronic yarn clearer for the purpose of detecting foreign fibers in yarns.

Abstract: A device for measuring the mass of fiber slivers contains an entry part for the fiber sliver to be measured and a measuring part adjoining the entry part. Arranged on the measuring part are two measuring members working on different measurement principles, specifically a so-called fiber-sliver mechanically, and so-called active-pneumatic measuring member for measuring the pneumatic pressure generated by the fiber sliver at a contraction. In addition to measuring the mass of fiber slivers, the device can be used for obtaining a characteristic variable for their composition or for separate regulation and monitoring in a control stage.

Abstract: The creation of fault diagnosis takes place using a knowledge-based evaluation of signals which signal the quality of the products produced, for example using spectrograms obtained in the investigation of parameters of textile fiber or filament structures. A first evaluation unit (NA) is provided for the detection of characteristic deviations of the spectrograms, which unit generates a so-called fault descriptor (SD) for each such deviation. A second evaluation unit (WA) uses a knowledge base (WB) to determine possible fault causes for each fault descriptor.

Abstract: A separation device for a warp drawing-in machine contains a dividing-off member for dividing off the foremost dropwire of a drop-wire stack. This dividing-off member includes a separating device and a transport device. The separating device subjects to pressure one of the end edges of the dropwire to be divided off to thereby bend this dropwire outwards. The transport device is provided for entry into the gap formed as a result of the outward bending of the dropwire and for conveying the separated dropwire away from the stack. With this separation device, all types of dropwires can be individually separated easily and at a high frequency.

Abstract: The warp threads (Ka) are clamped as a thread layer, are divided off individually from this and are stretched with a simultaneous measurement of the tensile force and/or stretching. These operations take place before the weaving process in a step of the weaving preparation process in which the warp threads are in the form of a prepared warp-thread layer. The device contains means (1, 2) for clamping the warp-thread layer, means (4) for dividing off the warp threads and means (FP) for measuring the tensile force and/or stretching of the divided-off warp threads, the means (1, 2) for clamping the warp-thread layer forming an integral part of a warp preparation machine, preferably of a knotting unit or of a drawing-in unit.

Abstract: An apparatus and method for effecting a warp change in weaving machines involves clamping the warp yarns of a new warp on a tying-in frame by way of clamping members. In addition, the warp yarns of the woven-out warp, the end portion of which has previously been pulled forwards over a specific length, are lifted over the tying-in frame and laid onto a roller assigned to the clamping members. The warp yarns of the woven-out warp are then fixed on the roller and pulled back out of the weaving machine over the specific length as a result of the rotation of this roller. These operations can be carried out by a single person, so that the warp change is simplified substantially. The tying-in frame and roller are mounted on a common carrier which is mountable on a warp-beam transport unit.

Abstract: A drawing unit contains two drawing zones, one of which is variable and driven by two motors. The desired draw is set by means of a control of the speed of one of the motors, preferably of the motor for the predrawing zone. This control of the speed is carried out by way of a draw correction value which is calculated from the deviation between the desired draw and the actual draw calculated from the speed of the fibre sliver at the entrance and at the exit of the drawing unit. This draw regulation allows a rapid reaction to fluctuations in the draw, simple correcting measures and drift-free operation.

Abstract: The thread monitor serves to detect the passage in a textile machine of a thread (F) moving in a direction transverse to the thread length. The monitor contains a pivoting member (B) which can be actuated by the thread and a sensor (7) monitoring the actuation of this pivoting member. The pivoting member (B) is designed in such a way that, during the passage of the thread, the pivoting member (B) is deflected from its rest position and then returned into its rest position, the sensor (7) being designed for detecting this return. The pivoting member (B) is elastic and in one-piece and the sensor (7) is sensitive to pressure. The monitor may be used in thread storage means and thread-transfer devices, particularly those in weaving and in warp-thread preparation apparatus.

Abstract: A method for producing uniform nonwoven webs from a supply of unordered fibre material includes discharging a quantity of fibre material onto a needle-type transport system having needles which are movable along a transport path, taking-up the fibre material by way of the needles on the needle-type transport system, transporting the fibre material in the needle-type transport system to an end of the transport system, discharging the fibre material onto an opening roller, separating the discharged fibre material on the opening roller and transferring the fibre material which has been separated on the opening roller onto a cylinder. An apparatus for producing uniform nonwoven webs includes a needle-type transport system for transporting fibre material along a transport path, an opening roller positioned along the transport path adjacent one end of the transport system and a rotatable cylinder positioned adjacent the opening roller for receiving the fibre material from the opening roller.

Abstract: The presence of yarns of a tentered yarn layer on a textile machine is checked by traversing a feeler transversely across a row of the threads to deflect the yarns. A pressure sensor of the feeler deflects each deflected yarn and generates a signal in response thereto. An optical sensor of the feeler detects each yarn and generates a second signal in response thereto which is compared to the first signal.

Abstract: A meter provides an arrangement for the optional connection of its voltage circuit to a current path or to a calibration system. The arrangement includes an opening, provided in the housing of the meter for inserting a contact device connected to the calibration system, and a pivoting lever. On insertion of the contact device into the opening, the pivoting lever can be moved from an operating position, connecting the voltage circuit to the current path, into a calibration position connecting the voltage circuit to the calibration system. Consequently, the arrangement can be changed over between the operating position and the calibration position with a minimum possible cost.