Abstract: An instrument is provided with several sensing elements to enable several parameters of a processed yarn to be measured or determined. In order to minimize the total sensing element/guide contact with the yarn within the complete process threadline, the yarn is guided through the instrument by contact only with the inlet and outlet guiding elements of the instrument and contact operative sensing elements. One particular instrument consists, in succession, of an interlace sensing device, a tension sensing device and an oil content sensing device. The electrical resistance of the yarn is measured between two pins of the oil content sensing device and in this case, the first pin is also a tension sensing pin of the instrument, and the second pin of the oil content sensing device is also the outlet guide of the instrument.

Abstract: Interlaced or twisted yarn is passed between an optical transmitter and receiver to produce an original signal which varies in response to the changes in dimension of the yarn. Such original signal is compared using cross-correlation with an expected signal as produced by an ideally processed yarn to produce a processed signal indicating by its value the degree of matching of the original signal with the expected signal. The amplitude of the processed signal is noted relative to a predetermined threshold value representing an acceptably processed yarn. The expected signal is devised by performing a frequency analysis on the original signal to establish a peak frequency which is used to determine the distance between nodes in an ideally processed yarn.

Abstract: A method of monitoring on-line the initial modulus of a spun and at least partially drawn textile yarn is provided. The method consists of forwarding the yarn from a forwarding point to a package, winding the yarn on the package whilst traversing the yarn adjacent the package at a periodically disturbed speed, and continuously measuring the short term variation in yarn tension due to the change in yarn path length between the forwarding point and the package. An alarm is initiated if the sampled data is equals predetermined limits. The initial modulus of the yarn is calculated from the amplitude of the tension variations.

Abstract: An instrument is provided with several sensing elements to enable several parameters of a processed yarn to be measured or determined. In order to minimize the total sensing element/guide contact with the yarn within the complete process threadline, the yarn is guided through the instrument by contact only with the inlet and outlet guiding elements of the instrument and contact operative sensing elements. One particular instrument consists, in succession, of an interlace sensing device, a tension sensing device and an oil content sensing device. The electrical resistance of the yarn is measured between two pins of the oil content sensing device and in this case, the first pin is also a tension sensing pin of the instrument, and the second pin of the oil content sensing device is also the outlet guide of the instrument.