Screw chip removal structure

A chip removal structure of a screw, the screw comprising a screw head, a shank extending downward from the screw head, the shank having an outer circumferential surface on which a thread is formed in a surrounding form, the shank having a lower end that is formed with a tapering tail section, wherein the tapering tail section comprises or does not comprise the thread, the tapering tail section or the tapering tail section and a portion of the thread being cut or press from two sides thereof toward a center to form a double-sided cutting tip section in the form of a plate, wherein an upper portion of the double-sided cutting tip section connected to the thread is formed, through cutting or pressing, with at least one chip removal grooves, wherein the chip removal groove has an inclination angle of 1°-89° or 91°-179°, wherein the chip removal groove exceeds a screw center line of the screw to each form an over-center-line chip removal groove, the chip removal grooves on the left side being 0.5 to 4.5 times in width of a rightmost chip removal groove.

A chip removal structure of a screw, the screw comprising a screw head, a shank extending downward from the screw head, the shank having an outer circumferential surface on which a thread is formed in a surrounding form, the shank having a lower end that is formed with a tapering tail section, wherein the thread is extended to the tapering tail section, the tapering tail section or the tapering tail section and a portion of the thread being cut or pressed from one side thereof toward a center to form a single-sided cutting tip section in the form of a plate or a single-sided tapering tail section plus a portion of the thread, wherein an upper portion of the single-sided cutting tip section connected to the thread is formed, through cutting or pressing, with at least one chip removal grooves, wherein the plurality of chip removal grooves have an inclination angle of 1°-89° or 91°-179°, wherein the plurality of chip removal grooves are not extended to a bottom of the tapering tail section and are formed on one, same side or two sides of the tapering tail section, and the plurality of chip removal grooves exceed a screw center line of the screw to each form an over-center-line chip removal groove, the chip removal grooves on the left side being 0.5 to 4.5 times in width of a rightmost chip removal groove.

A chip removal structure of a screw, the screw comprising screw head, a shank extending downward from the screw head, the shank having an outer circumferential surface on which a thread is formed in a surrounding form, the shank having a lower end that is formed with a tapering tail section, the thread being extended to the tapering tail section, wherein the tapering tail section is formed, through cutting or pressing, with a chip removal groove, the chip removal groove being not extended to a bottom of the tapering tail section, wherein the chip removal groove has an inclination angle between 1°-89°, the inclination angle of the chip removal groove being 8°-25°, the chip removal groove having a width equal to or greater than a radius of an outside diameter of the thread.