| 摘要 |
PURPOSE: A screw having ribs is provided to completely cover itself to a component to drive a screw and to shorten the time required to drive the screw. CONSTITUTION: A screw includes a screw part(1) and a head(2) having a dish-shaped hole. The two parts are connected to an intermediate conical part(3). The intermediate conical part reduces the danger, distributes the force to drive a screw into the end of an object as well as reinforces the connection. Also, the head is arranged on a surface(20) of the conical part, connected between an upper edge(22) and a base(23) of the head and includes a rib(21) inclined toward the direction to drive the screw. The rib has a triangular section so the screw as to be completely covered. |
