梅花孔薄頭 短牙螺絲

a) 此規範定義了 十字孔盤頭螺絲 (Cross recessed raised cheese head screws) 的規格. 這些螺絲具有凸起的圓柱形頭部, 一般常見孔型為 十字孔 type H (Phillips), 米字孔 Type Z (Pozi), 和 梅花孔 (Hexalobular socket / 6 lobe)

三角牙螺絲 DIN 7500

Square neck under head

a) DIN 7500 specifies self-tapping screws for metal, also known as thread-forming screws. These screws are designed to form or cut threads in a pre-drilled hole in metal materials, without requiring a pre-cut thread.

b) The screw shank has a three-lobe shape instead of a round cross-section, which reduces friction during installation, and facilitates smooth material displacement and efficient thread formation.

c) The long dog point (the extended, unthreaded tip of the screw) acts as a pilot, helping to align the screw with the pre-drilled hole during installation, and faciliates smooth installation.

d) A standard trilobe thread forming screw without dog point is avaialble upon request.

a) A ribbed neck screw is a type of fastener designed with a special feature on its shank or neck. Instead of a smooth or threaded surface, the neck of the screw has ribbed, serrated, or knurled features. These ribs or serrations provide additional grip and resistance when the screw is driven into a material, preventing it from rotating or loosening.

a) 鑽尾螺絲是一種設計用於在旋入過程中自動鑽孔並切割螺紋的螺絲，無需預先鑽孔。它具有類似鑽頭的尖端，能夠輕鬆穿透工件。這種設計有助於加快安裝過程並提高效率。鑽尾的形狀和材質會影響螺絲的鑽孔能力，從而決定在不同材料中的表現。

b) 頭部下方的鋸齒狀設計會在螺絲頭部與材質之間產生額外的摩擦，幫助防止螺絲鬆動。鋸齒狀表面為螺絲起子等工具提供更好的抓握力，使得在安裝過程中可以施加更大的扭矩，從而提高螺絲的固定效果。