Drill
AssigneeDrebo Werkzeugfabrik GmbH
InventorsMartin Stumpp, Alexander Zurn, Peter Kehrle, Tobias Berg
Life of this patent
Estimating the term…
Abstract
A drill with a drill flute (12) includes symmetrical fluted lands (20) helically extend around a core, wherein grooves (18) remain between the fluted lands, said grooves having a width (72) that exceeds the spine thickness or width (24) of the fluted lands (20), and wherein the grooves (18) comprise a convex core reinforcement (22) at the groove bottom thereof. The width (24) of the fluted lands (20) at the drill head side end (16) is smaller than at the shank side end (14) of the drill helix (12), and at least increases in certain areas. The core reinforcement (22) at the drill head side end (16) is more convex than at the shank side end (14), thus has larger radii (40, 42).
Claims19
A drill, said drill comprising:
- a drill helix (12) having a core, a drill end (16) and a shank end (14) and fluted lands (20) helically extending around the core, wherein said fluted lands are symmetrical in a cross sectional view taken perpendicularly to a longitudinal axis of the drill, wherein grooves (18) remain between the fluted lands, said grooves (18) having a width (72) that exceeds a spine width (24) of the fluted lands (20), and wherein the grooves (18) comprise a convex core reinforcement (22) at a groove bottom thereof,
- wherein the spine width (24) of the fluted lands (20) at an area disposed near a drill end (16) is smaller than at an area disposed near the shank end (14) of the drill helix (12) and increases in certain areas, and wherein a cross sectional maximum width of the core reinforcement (22) taken perpendicular to a longitudinal axis of the drill is greater at the drill end (16) of the core reinforcement (22) than a cross sectional maximum width of the core reinforcement (22) taken perpendicular to the longitudinal axis of the drill at the shank end (14) of the core reinforcement (22).
A drill, comprising:
- a drill helix (12) having a drill end and a shank end, wherein fluted lands (20) helically extend around a core, wherein said fluted lands are symmetrical in a cross sectional view taken along an axis that is perpendicular to a longitudinal axis of the drill, wherein grooves (18) remain between the fluted lands (20), said grooves having a width (72) that exceeds the spine thickness or width of the fluted lands (20), and wherein the grooves (18) comprise a convex core reinforcement (22) at the groove bottom thereof,
- wherein the width (24) of the fluted lands (20) at the drill end (16) is smaller than at the shank end (14) of the drill helix (12), and decreases in certain areas, and wherein a cross sectional maximum width of the core reinforcement (22) taken perpendicular to the longitudinal axis of the drill is greater towards the shank end (14) than at the drill end (16).
Dependencies are inferred from the claim text.