An Analysis of the Mechanical Forces in Latch Needle Cam Systems

The majority of textile fabrics are either woven or knitted. Knitted fabrics are most frequently produced on weft knitting machines. The range of machinery is very diverse but the same basic mechanism is employed to convert textile yarn into knitted textile fabric. The mechanism is a specialized needle and cam system known as a latch needle cam system. This paper develops a general model for the mechanical forces that arise in normal operation of a latch needle cam system. The limitations of previous models are noted. The model may be used to predict mechanical forces for any specified cam profile and for the most common needle and cam arrangements. The model will be used in a following paper on yarn forces in latch needle cam systems. The performance of the model will be reported in a following paper describing an experimental programme and experimental results