Patent ID: 6520055
Filing Date: 2003-02-18
Classification: B25B

Abstract:
Screwdriver or screwdriver bit (S), having an input end (1), an output end (2) and a shank (4) located between these ends, the shank extending in a longitudinal direction along an axis of rotation of the screwdriver or the bit from the input end to the output end, the output end being forward of the shank and including a centre section (8) disposed at a forward part of the output end and extending transversely of the axis, wherein the output end is profiled in the form of a group of ribs spaced apart by notches and having at least three ribs (7), which ribs (7) extend from the centre section (8) radially outward from the axis of rotation and longitudinally parallel to the axis, each rib having a front flank (13) and a rear flank (14) wherein the front flank is ahead of the rear flank in a clockwise direction of rotation of the screwdriver or bit about the axis, the rear flank of one of the ribs and the front flank of a successive one of the ribs defining one of the notches of which a base of the notch extends between said one of the ribs and said successive one of the ribs, wherein a front part of each of the ribs is oriented at an angle to the axis of rotation, the front and the rear flanks in a forward region of each of the ribs run substantially parallel to one another, in which forward region of each rib a substantially tangent surface with respect to each front flank (13) lies on a diametral surface through the axis of rotation, wherein each of the notches (9) runs in said longitudinal direction, wherein said front flank and said rear flank (13, 14) of each of the ribs are curved away from one another such that in each of said notches, a boundary outer edge (13â€²) of the front flank (13), in a further course of a curvature of the front flank (13) in a direction of the axis, is curved towards the notch base over a smaller circumferential angle than a further notch boundary edge (14â€²) of the rear flank (14).