Helical broach for roughing
AssigneeMitsubishi Heavy Industries, Ltd.
InventorYasuhito Katsuki
Life of this patent
Estimating the term…
Abstract
A helical broach 1 for roughing includes a cutting tooth part 30 in which n spline teeth 31 are arranged side by side in an axial direction. The spline teeth 31 each include cutting teeth 32 which are arranged at a predetermined helix angle. The cutting teeth 32 each have an acute angle portion and an obtuse angle portion on both sides thereof in a circumferential direction. The cutting teeth disposed on the first to n−1th spline teeth 31 (S1 to Sn−1) in the circumferential direction are each formed in such a way that its height on the acute angle portion side differs from that on the obtuse angle portion side. The cutting teeth (Sn) of the nth spline tooth (Sn) are each formed in such a way that its height stays constant in the circumferential direction.
Claims3
A helical broach for roughing comprising
- a cutting tooth part in which a plurality of spline teeth are arranged side by side in an axial direction, the spline teeth each including cutting teeth which are arranged at a predetermined helix angle, the cutting teeth each having an acute angle portion and an obtuse angle portion on both sides of a cutting edge thereof in a circumferential direction for cutting a work piece, wherein
- on an obtuse angle portion side of the cutting edge of each of the cutting teeth disposed in the circumferential direction on part of the spline teeth, an inclined portion or a tapered portion for cutting the work piece is formed by gradually increasing a height of the cutting tooth from the obtuse angle portion side toward the acute angle portion side so that the height of the cutting tooth on an acute angle portion side differs from that on the obtuse angle portion side, the part of the spline teeth being spline teeth disposed sequentially from a leading one of the spline teeth, and
- the cutting teeth of the other part of the spline teeth are each formed in such a way that its height stays constant in the circumferential direction.
Dependencies are inferred from the claim text.