Apparatus and method for adjusting the stitch on a circular knitting machine

An automatic stitch cam adjustment mechanism for a circular knitting machine is disclosed. The knitting machine includes a plurality of knitting needles supported in a rotating needle cylinder for vertical movement parallel to the axis of rotation of the needle cylinder. A plurality of cam support brackets surround the needle cylinder, and a plurality of stitch cam support members are slidably mounted on the cam support brackets for vertical movement thereon. Stitch cams are mounted on the stitch cam support members for engaging the needles and lowering the needles to a loop formation point. A drive motor is connected to each of the stitch cam support members for moving the stitch cam support members up and down. Sensors are included for (1) measuring the position of the movable support members along the vertical path of movement, (2) detecting the rotational speed of the needle cylinder, and (3) measuring a feeding characteristic of the yarn such as yarn feed tension or quantity. A controller is operatively connected to the drive motors and sensors for comparing each of the sensed values with a predetermined knitting machine operating standard and actuating the drive motors for adjusting the stitch cams as needed.