Abstract: A screw includes a screw cap and a shank extending downward from the screw cap. The shank has an outer circumferential surface on which a thread is formed. The shank has a lower end forming a tip section. The screw cap is extended downward to form a conic section. The conic section is provided thereon with a reverse prevention mechanism, which is constructed to include at least one step structure. After the screw is screwed into a workpiece, in an attempt to screw the screw out of the workpiece, the reverse prevention mechanism providing a blocking and resisting effect to prevent the screw from being readily screwed out of the workpiece and thus, a reverse prevention effect of the screw can be enhanced to thereby improve overall performance of use of the screw.

Abstract: A screw includes a screw cap and a shank extending downward from the screw cap. The shank has an outer circumferential surface on which a thread is formed. The shank has a lower end forming a tip section. The screw cap is extended downward to form a conic section. The conic section is provided thereon with a reverse prevention mechanism, which is constructed to include at least one step structure. After the screw is screwed into a workpiece, in an attempt to screw the screw out of the workpiece, the reverse prevention mechanism providing a blocking and resisting effect to prevent the screw from being readily screwed out of the workpiece and thus, a reverse prevention effect of the screw can be enhanced to thereby improve overall performance of use of the screw.

Abstract: A structure of a screw is provided, including a shank extending downward from a screw head. The shank has an outer circumferential surface on which a thread extending spirally around is formed. The shank has a lower end forming a tapering tail section. The thread does not extend into the tapering tail section. The tapering tail section is provided with at least one rib raised on a surface thereof. The rib has an edge that is made in a wavy-toothed form so as to improve the capability of the screw for cutting and chip removal and also to reduce a screw-in torque of a screwing operation of the screw to thereby achieve an effect of saving labor and time in conducting an operation and also to prevent the occurrence of defects of wood cracking to enhance the quality of an operation conducted with the screw.

Abstract: Disclosed is a chip removal structure of a screw. The screw includes a screw head. A shank extends downward from the screw head. The shank has an outer circumferential surface on which a thread is formed in a surrounding form. The shank has a lower end that is formed with a tapering tail section. The thread is extended to the tapering tail section. The tapering tail section is formed, through cutting or pressing, with two or more chip removal grooves. The spacing distance of the chip removal grooves can be adjusted as desired. The chip removal grooves are set at an inclination angle and any one of the chip removal grooves may exceed or may not exceed a screw center line. The chip removal grooves on the left side are each 0.5 to 4.5 times in width of the chip removal grooves on the right side.

Abstract: A screw includes a screw cap and a shank extending downward from the screw cap. The shank has an outer circumferential surface on which a thread is formed. The shank has a lower end forming a tip section. The screw cap is extended downward to form a conic section. The conic section is provided thereon with a reverse prevention mechanism, which is constructed to include at least one step structure. After the screw is screwed into a workpiece, in an attempt to screw the screw out of the workpiece, the reverse prevention mechanism providing a blocking and resisting effect to prevent the screw from being readily screwed out of the workpiece and thus, a reverse prevention effect of the screw can be enhanced to thereby improve overall performance of use of the screw.

Abstract: A screw includes a screw cap and a shank extending downward from the screw cap. The shank has an outer circumferential surface on which a thread is formed. The shank has a lower end forming a tip section. The screw cap is extended downward to form a conic section. The conic section is provided thereon with a reverse prevention mechanism, which is constructed to include at least one step structure. After the screw is screwed into a workpiece, in an attempt to screw the screw out of the workpiece, the reverse prevention mechanism providing a blocking and resisting effect to prevent the screw from being readily screwed out of the workpiece and thus, a reverse prevention effect of the screw can be enhanced to thereby improve overall performance of use of the screw.

Abstract: A screw includes a screw cap and a shank extending downward from the screw cap. The shank has an outer circumferential surface on which a thread is formed. The shank has a lower end forming a tip section. The screw cap is extended downward to form a conic section. The conic section is provided thereon with a reverse prevention mechanism, which is constructed to include at least one step structure. After the screw is screwed into a workpiece, in an attempt to screw the screw out of the workpiece, the reverse prevention mechanism providing a blocking and resisting effect to prevent the screw from being readily screwed out of the workpiece and thus, a reverse prevention effect of the screw can be enhanced to thereby improve overall performance of use of the screw.

Abstract: Disclosed is a chip removal structure of a screw. The screw includes a screw head. A shank extends downward from the screw head. The shank has an outer circumferential surface on which a thread is formed in a surrounding form. The shank has a lower end that is formed with a tapering tail section. The thread is extended to the tapering tail section. The tapering tail section is formed, through cutting or pressing, with two or more chip removal grooves. The spacing distance of the chip removal grooves can be adjusted as desired. The chip removal grooves are set at an inclination angle and any one of the chip removal grooves may exceed or may not exceed a screw center line. The chip removal grooves on the left side are each 0.5 to 4.5 times in width of the chip removal grooves on the right side.

Abstract: A structure of a self-drilling screw is disclosed. The screw includes a screw head and a shank extending downward from the screw head. The shank has an outer circumferential surface, around which a thread is circumferentially formed. The shank has a lower end forming a drilling tip section. The thread is extended or not extended into the drilling tip section. The drilling tip section is formed with at least one first chip removal groove. The first chip removal groove has an upper end and at least one second chip removal groove is arranged to extend from the upper end along the shank in a direction toward the screw head.

Abstract: A structure of a screw is provided, including a shank extending downward from a screw head. The shank has an outer circumferential surface on which a thread extending spirally around is formed. The shank has a lower end forming a tapering tail section. The thread does not extend into the tapering tail section. The tapering tail section is provided with at least one rib raised on a surface thereof. The rib has an edge that is made in a wavy-toothed form so as to improve the capability of the screw for cutting and chip removal and also to reduce a screw-in torque of a screwing operation of the screw to thereby achieve an effect of saving labor and time in conducting an operation and also to prevent the occurrence of defects of wood cracking to enhance the quality of an operation conducted with the screw.

Abstract: A screw includes a screw cap and a shank extending downward from the screw cap. The shank has an outer circumferential surface on which a thread is formed. The shank has a lower end forming a tip section. The screw cap is extended downward to form a conic section. The conic section is provided thereon with a reverse prevention mechanism, which is constructed to include at least one step structure. After the screw is screwed into a workpiece, in an attempt to screw the screw out of the workpiece, the reverse prevention mechanism providing a blocking and resisting effect to prevent the screw from being readily screwed out of the workpiece and thus, a reverse prevention effect of the screw can be enhanced to thereby improve overall performance of use of the screw.

Abstract: Disclosed is a method for manufacturing a screw with helical chip discharge channel, including providing a blank, subjecting an end of the blank to form a head and subjecting the blank to rolling to form one or more sections of threads. The screw is formed with one or more helical chip discharge channels, which can be of different helical angle according the different applications. The chip discharge channel can be formed by milling, rolling, or combined rolling and milling. The chip discharge channel is extended into the threads to form tapping edges. As such, the tapping operation is made effortless and the shape of the tapped thread excellent. The extending angle of the chip discharge channel can be changed according to different materials of the workpiece to be fastened. The length of the chip discharge channel can be selected according to different applications.