Circular knitting machine for hosiery or the like

A circular knitting machine for hosiery or the like, comprising at least one needle cylinder which has a vertical axis and has, on its lateral surface, a plurality of axial slots, each of which accommodates a needle and a needle actuation element, wherein said actuation element comprises at least one connecting element, which is provided, on its side directed toward the outside of the needle cylinder, with at least one movable heel;

• said connecting element being able to oscillate on a radial plane of the needle cylinder for the transfer of said movable heel from an active position, in which said movable heel protrudes radially from the corresponding axial slot of the needle cylinder to engage corresponding connecting element actuation cams which face the lateral surface of the needle cylinder and define paths which can be followed by said movable heel, in the active position, as a consequence of the actuation of the needle cylinder with a rotary motion about its own axis with respect to said connecting element actuation cams, to an inactive position, in which said movable heel is contained in said axial slot of the needle cylinder so as to not engage said connecting element actuation cams, and vice versa;
• said connecting element actuation cams comprising at least one extraction cam or one retraction cam, which has a portion whose profile is inclined with respect to an ideal plane which is perpendicular to the axis of the needle cylinder and can be engaged by said movable heel in the active position;
• extraction means being provided which act on said connecting element to transfer its movable heel from said inactive position to said active position and to keep said movable heel of the connecting element in said active position substantially over the entire extension of said portion of the extraction cam or of the retraction cam.