Practical cross recessed screw

Abstract

The invention discloses a practical cross recessed screw which comprises a screw body, a screw head, a cross recess, an external thread, a first conical surface and a second conical surface. The upper portion of the screw body is connected with the screw head. The screw head is a circular truncated cone body, and a first chamfer is formed in the circular side line of the upper end face of the screw head. Four side grooves which are evenly distributed in the circumferential direction are formed in the first chamfer. The cross recess is formed in the end, away from the screw body, of the screw head. The external thread is arranged on the partial outer surface of the screw body, and tracking grooves are formed in the outer edge of the external thread. A first conical surface is arranged on the screw body and located below the external thread, and the first conical surface and the screw body are provided with a second conical surface. According to the practical cross recessed screw, the total length of the first conical surface and the second conical surface is designed to be one half of the length of the screw body, so that a longer pressing-in distance is achieved when the screw enters media at the beginning, and subsequent screwing-in of the screw is better facilitated; second chamfers are formed in intersection lines of the cross recess and the top head end face, and therefore the cross recess cannot be damaged when a hammer is used for knocking the screw.

Description

【Technical field】 [0001] The invention relates to the technical field of hardware fittings, in particular to the technical field of practical cross-recessed screws. 【Background technique】 [0002] Screws can be divided into: slotted ordinary screws, hexagon socket and hexagon socket flower screws, cross recessed ordinary screws, ring screws, set screws, self-tapping screws, self-tapping locking screws. Among them, the cross-recessed ordinary screw has similar functions to the slotted ordinary screw and can be replaced with each other, but the groove shape of the cross-recessed ordinary screw has higher strength, is not easy to twist and bald, and has a more beautiful appearance. When in use, it must be loaded and unloaded with the matching cross-shaped screwdriver. However, there are many inconveniences in the use of cross-recessed ordinary screws. For example, when the screw first enters the medium, time is often wasted on fixing the screw; when the screw is damaged in the...

AI Technical Summary

Problems solved by technology

However, there are many inconveniences in the use of cross-recessed ordinary screws. For example, when the screw first enters the medium, time is often wasted on fixing the screw; when the screw is damaged in the cross-recess, it is difficult to remove the screw from the medium by means of a screwdriver. Take it out; the debris produced by the friction between the thread on the screw and the medium has nowhere to go, which will hinder the further tightening of the screw

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