Self-boring and self-tapping screw
AssigneeSpax International GmbH & Co. KG
InventorFrank Langewiesche
Life of this patent
Estimating the term…
Abstract
The invention relates to a self-boring and thread-forming tapping screw having a screw shaft with a screw tip at one end and at the other end a force application member for the transmission of a turning moment. The screw shaft includes a threaded section with the screw tip and an adjacent thread-free section of the shaft including the force application member. The threaded section has a shaft core and a self-tapping thread. The threaded section includes a core section axially displaced from the tip and having a polygonal core cross section. Corners of the core cross section define an enveloping circle with an enveloping circle diameter larger than a shaft diameter of the thread-free section.
Claims9
A self-boring and self-tapping screw comprising a screw shaft with a screw tip at one end extending axially to a force application member for the transmission of a turning torque at the other end, the screw shaft including a threaded section disposed between the screw tip and a thread-free section of the shaft, the thread-free section including the force application member, the threaded section including a shaft core and a thread, the threaded section further includes a core section axially displaced from the screw-tip, the core section has a polygonal core cross section with corners defining an enveloping circle having an enveloping circle diameter larger than a shaft diameter of the thread-free section of the shaft;
- wherein the thread runs along the entire core, including the polygonal core section, and the polygonal core section is provided within the threaded section adjacent the thread-free section of the shaft.
Dependencies are inferred from the claim text.