Abstract: A method of and apparatus for monitoring the processing of a multifilament yarn to indicate a number of protrusions in the yarn is provided. In this method, a multifilament yarn is passed through a light beam directed from a light emitting device to a light receiving device, and the amount of light received by the light receiving device is measured at predetermined time intervals. From the measured amounts of light over a predetermined time period a measuring and computing device produces a frequency distribution, and a threshold level representative of an ideal yarn is calculated from the frequency distribution. The number of measurements that fall outside that threshold level is recorded and is indicative of the number of filament breaks and loops in the yarn.

Abstract: A method of and apparatus for monitoring the processing of a multifilament yarn to indicate a number of protrusions in the yarn is provided. In this method, a multifilament yarn is passed through a light beam directed from a light emitting device to a light receiving device, and the amount of light received by the light receiving device is measured at predetermined time intervals. From the measured amounts of light over a predetermined time period a measuring and computing device produces a frequency distribution, and a threshold level representative of an ideal yarn is calculated from the frequency distribution. The number of measurements that fall outside that threshold level is recorded and is indicative of the number of filament breaks and loops in the yarn.

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.