Opto-Electronic Testing of Movable Operating Elements of a Knitting Machine in the Process of Manufacturing Jersey Fabrics

The possibilities of detecting flaws of basic elements of knitting needles, namely, the needle beard (hook) and the latch, in real time are considered. The paper is devoted to consideration of the basic problems of this testing, namely, impact phenomena appearing in the interaction between the needle and the cam, large (greater than 200%) dispersion of the needle location in the dynamic regime, and unsteady (in the optical sense) background whose characteristics vary not only from one to another machine but also during the working shift. Optic characteristics of needles as objects of optic testing are investigated. Box-diagram and characteristics of transmitter-receiver units of testing the needle beards and latches are given and their optimum parameters are estimated analytically and confirmed experimentally. The results of a comparison of the designed device with standard mechanical probes and the best foreign analog are presented. The advantages of the device demonstrated in both cases are related not only to change in the underlying physical principle, but in the great measure also with a more adequate structural and algorithmic organization.