Abstract: An upstanding knitting cylinder carries a multiplicity of needle jacks on its circumference. In order to selectively more the needle jacks up and down on the knitting cylinder during the rotation thereof, a vertical flow of selector fingers capable of engagement with butts on the needle jacks are rigidly mounted to respective sleeves which in turn are rotatably mounted on fixed horizontal shafts disposed in parallel spaced relation to one another in a vertical plane. Disposed opposite the respective sleeves on the fixed shafts are several pairs of electromagnet assemblies which are arranged in two diagonal rows in order to reduce the vertical dimension of the needle selector. An armature secured to each sleeve is held opposite each pair of electromagnet assemblies so as to be alternately attracted thereby, with the consequent bidirectional rotation of the sleeves and, therefore, the pivotal motion of the selector fingers to engage and disengage the needle jack butts.

Abstract: A piezoelectric needle selector utilizes an upstanding knitting cylinder having a multiplicity of needle jacks mounted thereto for independent movement in a direction parallel to the axis of the knitting cylinder. A plurality of piezoelectric actuators, each having a stack of planar piezoelectric elements coupled at one end to a plunger, are mounted via respective holders to a fixed support frame disposed adjacent the knitting cylinder. The selective application of voltage pulses to the piezoelectric actuators results in the linear travel of the associated plungers toward and away from the knitting cylinder. The linear travel of the selected plungers is translated into the movement of the desired needle jacks up and down on the knitting cylinder, as by several needle select levers pivoted by the plungers and acting on the usual butts on the needle jacks.

Abstract: An upstanding knitting cylinder carries a multiplicity of needle jacks on its circumference. In order to selectively move the needle jacks up and down on the knitting cylinder during the rotation thereof, a vertical row of selector fingers capable of engagement with butts on the needle jacks are rigidly mounted to respective sleeves which in turn are rotatably mounted on fixed horizontal shafts disposed in parallel spaced relation to one another in a vertical plane. Disposed opposite the respective sleeves on the fixed shafts are several pairs of electromagnet assemblies which are arranged in two diagonal rows in order to reduce the vertical dimension of the needle selector. An armature secured to each sleeve is held opposite each pair of electromagnet assemblies so as to be alternately attracted thereby, with the consequent bidirectional rotation of the sleeves and, therefore, the pivotal motion of the selector fingers to engage and disengage the needle jack butts.

Abstract: A knitwork tensioning device has a fabric locking mechanism normally disposed in the lower needle cylinder of a double cylinder circular knitting machine. The fabric locking mechanism has a set of locking fingers capable of fluid pressure actuation for locking the fabric being knitted against the bottom end of an inner movable tube within the upper needle cylinder. The fabric locking mechanism is itself capable of fluid pressure actuation for movement into the upper needle cylinder. Locked against the inner movable tube by the locking fingers, the fabric is stretched as the fabric locking mechanism travels with the inner movable tube up into the upper needle cylinder under fluid pressure. The upper needle cylinder has also mounted therein an outer movable tube slidably fitted over the inner movable tube.

Abstract: A device for selectively lifting a multiplicity of needles which are mounted to an upstanding, rotatable cylinder for up and down sliding motion. Each needle has a shank with two butts formed in vertically spaced positions thereon, so that there are formed tow rows of such butts extending circumferentially of the cylinder. The upper one, for example, of the two rows of butts includes a group of butts that are longer than the other butts of the same row. Slidably supported adjacent the cylinder are a pair of cams which are independently moved, as by solenoids, toward and away from the cylinder and which have sloping cam surfaces for relatively sliding engagement with the respective rows of butts when the cams are thrusted toward the cylinder in rotation.