Abstract: A single-cylinder circular knitting machine with anti-twist device includes a needle cylinder in which there is a cavity which is open upward and can be connected, through a perforated region which extends around the needle cylinder axis, to a suction device so as to retain the product during its forming against the walls of the cavity. An inner tubular body is arranged inside the cavity and can be connected to a suction device for drawing the finished product through the inner tubular body. The inner tubular body is controllably movable along an axial direction from a first position, in which its upper end is proximate to the upper end of the needle cylinder, to a second position, in which its upper end is proximate to the bottom of the cavity.

Abstract: The thread guide structure for double-cylinder circular knitting machines comprises a thread guide body which has an elongated configuration and has, proximate to one of its longitudinal ends, a thread dispensing passage. The thread guide body has a first part and a second part which are mutually articulated proximate to an intermediate region of the thread guide body. The first part, which is provided with the thread dispensing passage, is oscillatable with respect to the second part about an oscillation axis which is arranged transversely to the longitudinal extension of the thread guide body.

Abstract: The thread feed unit has a supporting block which can be associated with a knitting machine laterally to the needle cylinder or cylinders and is provided with at least one thread guide which has a body provided with an elongated configuration associated with a supporting element and slidable along a direction substantially parallel to its longitudinal extension. The supporting element is associated with the supporting block for oscillation about an oscillation axis transverse to the sliding direction of the thread guide body. A first thread guide actuator is provided and controllably acts on the supporting element to oscillate the thread guide about the oscillation axis, and a second actuator controlling the thread guide body to slide it longitudinally with respect to the supporting element. The first actuator and the second actuator are associated with the supporting block and can be actuated independently of one another.

Abstract: The twin-cylinder circular knitting machine with knitted fabric tensioning device having members for retaining the fabric proximate to a knitting forming region. A first fluid-activated piston is accommodated in the upper needle cylinder and is provided with a hollow stem which is open at its ends. The lower end of the stem is engageable, by means of the sliding of the piston parallel to the axis of the needle cylinders, with the knitted fabric being formed in order to apply tension thereto. The retention members have dimensions for allowing the stem to slide outside of the retention members. The tensioning device also has an auxiliary actuation piston which acts on the piston to achieve its descent at a controlled rate at least until the lower end of the stem of the piston makes contact with the fabric in the region comprised between the retention members and the knitting forming region.

Abstract: The circular knitting machine has a pneumatic service circuit with pneumatically actuated service devices arranged around the needle cylinder. An annular body surrounds the needle cylinder, and a main duct is defined in the annular body. The main duct is supplied with pressurized air and is connected to the supply ducts of pneumatic actuators which actuate the service devices. Valve for operating the actuators are arranged between the actuator supply ducts and the main duct.

Abstract: The circular knitting machine for socks, stockings or the like, in particular for producing knitting with towelling stitches, comprises, at the set of knitting-forming cams which actuate the motion of the needles during the engagement of the thread or threads at one feed of the machine, an additional cam. The additional cam is arranged above the central cam and defines a descending portion which is engageable with the heel of the needles, excluded from knitting at that feed and raised with respect to the needles which knit at that feed. The controlled lowering of the needles which do not knit at the feed facilitates the positioning of the thread or threads fed at the feed and the correct forming of the loops by the needles which knit at that feed.

Abstract: The machine has a rotatable needle cylinder and a casting-off sinker actuation device including a coaxial sinker ring supporting a cam and an external countercam. The needle cylinder supports a plurality of casting-off sinkers each having a heel which follows a path, extending around the needle cylinder axis, which is partially defined by the cam and the countercam. A pin is connected to the countercam and is engaged by an actuation element associated with the sinker ring and bilaterally engaging the pin. The actuation element is controllably activatable for bilaterally moving the countercam with respect to the needle cylinder along a direction having a radial component, toward or away from the axis of the needle cylinder.