Hilti Aktiengesellschaft

Felix Ferlemann

Gerd Daubinger

Horst Rahmsdorf

Sven Jochmann

Horst Rahmsmdorf

Holger Wirtz

Daniel E Spielberg

Frank Brandenburg

A screw driving device () for a hand tool drilling device () includes a screw magazine () for successive feeding of screws or bolts (), a feeder block () that can be axially displaced against the force of a feeder spring (), which at least partially supplies screws () during the back and forth reciprocating movement of the feeder block (), and a driving tool () that can be coupled rotationally in form locked manner with a screw head (), wherein the driving tool () axially moveably receives a rotatingly driven drilling tool () in a coaxial hollow inner space and is spring biased axially by a clutch spring () relative to the screw driving device in a rotation driver position X, in which a drilling tool tip () is axially spaced from the screw head () and is coupled rotationally form locked with the driving tool ().

Screw driving device

A self-drilling screw including a drilling section (1; 4) adjoining a thread section (2; 5) of the screw and formed of first (11; 41) and second (12; 42) parts arranged one after another, within the drilling section (1; 4) having first and second cutting edges (15, 16; 45, 46) a radial extension of which is symmetrical with respect to the longitudinal axis of the screw, in the first, in a drilling direction, part of the drilling section (1; 4), with at least a portion of the second part (12, 42) of the drilling section (1, 4), which is located between the first part (11, 41) and the thread section (2; 5), having in a region of one of the first cutting edges (15; 45), a radial extension (R1; R3) corresponding, at most, to a half of a root diameter (D1; D3) of the thread section (2; 5), and with the second cutting edge (16, 46) having in the second part (12, 42) of the drilling section (1, 4), a radial extension (R2; R4) which is smaller than a half of a pitch diameter (D2; D4) of the thread section (2, 5) and corresponds at least to the half of the root diameter (D1; D3) of the thread section (2; 5).

Self-drilling screw

A rotary tool for imparting rotation to a drill or an attachment element (2), and including a rotation-imparting element (14), and apparatus (6) for storing a cooling medium, and a conduit (7) for delivering the cooling medium to an operational side end region of the drill or of the attachment element (2).

Rotary tool with a cooling apparatus

Growing community of inventors

Windach, Germany

Felix Ferlemann