Abstract: In a knitting machine, a plurality of stepping motors (10) is controlled by an electronic control unit (35) and each motor transmits horizontal oscillations to a tube bar (5). Each oscillation is built up of a plurality of horizontal-movement steps, each step being delimited between two limit points to which a centered positioning of the threading tubes (8) in the spaces defined between the needles (9) corresponds. A photoelectric sensor interlocked to the control unit detects the passage before a given read point of optical locators reproduced on plate-like elements, each associated with the drive shaft of one of the motors, in order to check whether the individual bars perform correct movements. Should a cutoff in the electric supply to the knitting machine (4) occur, each tube bar (5) would be stopped at anyone of the limit points.

Abstract: A circular knitting machine in which the inactivation or activation of a vertical jack below each needle is determined by a flexible fork located radially of the cylinder within a ring structure completely surrounding the machine cylinder and rigid therewith. A number of forks and radial grooves equal to the number of needles is provided, said forks being able to flex within said grooves and being selected by a magnetic force.

Abstract: A triple needle height selective means for knitting machines. For each needle, there is provided two columns of perforations in a pattern strip and two selector levers receiving the dictates from the columns of perforations. A racket is associated with an individual needle having two heads and a single effective tail, the heads being positioned at two distinctive heights. Depending upon which selector lever is activated, motion is transmitted through the racket to elevate the needle to a corresponding height.