| 主权项 |
1. A cutting tip having a conical body substantially rotationally symmetric about a center axis and having a profile in a longitudinal section through the center axis, the profile comprising:
a convex portion extending from a cutting end situated on the center axis, to an inflection point located at an axial and radial distance from the cutting end, towards a base portion of the body; a concave portion extending from the inflection point to a point located at a greater radial and axial distance from the cutting end and axially closer to the base portion, at least one of the concave portion and the generally convex portion including a first linear portion, defined by a portion of a first line, the first line extending from a first point at a first radial position at an angle of about 45 degrees relative to the center axis, to a second point at a second radial position and axially spaced from the first point, and a second linear portion defined by a portion of a second line, the second line extending from a third point, forming an approximate middle point of the first line, to a fourth point at the second radial position and at an axial distance from the second point corresponding to about half a length of the first line; and a transition portion disposed between each two adjacent linear portions, each transition portion having a radius that provides a smooth transition between the adjacent linear portions. |
