A circular knitting machine comprises a rotatable knitting needle cylinder which carries a plurality of knitting needles through knitting stations. A needle-moving jack is pivotally connected with each of the knitting needles and is movable in a needle-raising stroke and a needle-lowering stroke to effect needle raising and lowering, respectively. Each of the needle-moving jacks has a butt thereon which is received in a cam track which operates to effect the raising and lowering of the needle-moving jack. A mechanism is provided for controlling the operation of each knitting needle as it progresses through the stations. The mechanism specifically effects pivoting of the needle-moving jack so that the butt thereon is removed from the cam track. The means which effects the pivoting movement of each needle-moving jack comprises a movable selector jack which cooperates with the needle-moving jack and effects the pivoting movement of the needle-moving jack in response to actuation of electromagnetic means. The electromagnetic means controls the movement of each selector jack so that a selector jack is moved to effect the pivoting movement of the needle-moving jack or not moved to allow the needle-moving jack with which it is associated to remain with its butt in the cam track.
This application is a continuation of co-pending application Ser. No. 303,546, filed Nov. 3, 1972, now abandoned. Application Ser. No. 303,546 is a division of application Ser. No. 150,052, filed June 4, 1971, now U.S. Pat. No. 3,742,733. Application Ser. No. 150,052 was a continuation-in-part of application Ser. No. 824,227, filed May 13, 1969, now abandoned.
The needle selection device has multiple selectors arranged in axial grooves formed in the skirt of the needle cylinder, each selector arranged below a needle and oscillatable in a radial plane of the needle cylinder from an active position, in which a butt protrudes radially from its groove, for the engagement of the butt with cams for actuating the selectors arranged around the needle cylinder to move the selectors along their groove in the needle cylinder so as to activate the overlying needle, to an inactive position, in which the selector is positioned in its groove in the needle cylinder so that it does not interfere with the selector actuation cams. The device has selector extraction elements to transfer the selectors from the inactive position to the active position and selection elements to transfer the selectors from the active position to the inactive position or to keep them in the active position. Each selector is provided with a selection element protruding radially from the grooves of the needle cylinder and oscillatable in the plane of arrangement of its selector. The selection element is made of a material that can be magnetized, and an electromagnet is provided for magnetizing the selection element and magnetic elements interact with the selection element after magnetization to make it oscillate into an idle position, in which the selection element engages a selector sinker cam laterally facing the needle cylinder, or into an active position, in which the selection element does not interfere with the sinker cam.
For needle selection in a circular knitting machine, a device is disclosed which comprises a plurality of superimposed selecting levers, individually pivoted to a common structure and selectively movable between a position where they do not interfere with the pattern jack butts and a position where they interfere therewith, to urge them toward the needle cylinder. The selective movement is accomplished by means of electromagnets, one for each selecting lever, which are energized in accordance with the machine knitting program and move intermediate, preferably rod-like, drive elements the axial displacement whereof results in a pivotal movement of the respective selecting levers between the cited positions. The engagement of the intermediate elements with the selecting levers is accomplished through geometrical coupling. A minimal force is sufficient for the actuation, so that the size of the electromagnets can be minimized, while a prompt response is ensured.
A circular knitting machine, comprising a footing with a rotatable, vertical needle cylinder, axial slots on the outer lateral surface of the needle cylinder, that accommodate each a needle, a sub-needle arranged below each needle in a corresponding axial slot connected bilaterally to the needle and having a radial heel, the sub-needle being oscillatable on a radial plane of the needle cylinder, sub-needle actuation cams, for producing movement of the sub-needle along the axial slot to actuate the overlying needle.
Disclosed is a knitting needle driving mechanism of a jacquard knitting machine for driving knitting needles by using piezo-electric elements in which a rear end portion of a piezo-electric body is movably supported in a groove of a supporting body or a housing, a front end portion of the piezo-electric body is movably connected to a rear end portion of a finger which is arranged so as to be aligned with the piezo-electric body and supported at the rear end portion thereof by the supporting body or the housing, and an intermediate portion between the front end portion and the rear end portion of the piezo-electric body is inserted into a rotatable member rotatably mounted on the supporting body or the housing. This knitting needle driving mechanism is small in size, high in response speed and prolonged in lifetime.
