Patent classifications
Y10T29/49524
Rim for a bicycle wheel and bicycle wheel comprising such a rim
A rim (5) for a bicycle wheel having a body (20) with a substantially annular extension with a radially outer portion (22) shaped for coupling with a tire is disclosed. The radially outer portion (22) has a hole (39) for an inflation valve. The radially outer portion (22) also includes, at the hole (39) and/or in an area proximal to the hole (39), at least one cross section having a different shape from that at an area distal from the hole, so as to form at least one second surface discontinuity (35) along the annular extension of the radially outer portion (22). The second discontinuity (35) makes it easier to assemble to wheel and allows an optimal coupling to be made between the rim (5), inflation valve, and tire, in the case of a tubeless wheel, and between rim (5), air chamber and tire, in the case of a wheel with an air chamber.
Method of forming a sheet steel workpiece
The invention relates to a method for the forming of a workpiece, in particular a blank, composed of sheet steel, in which method the following steps are performed in succession: providing a workpiece composed of multiple steel layers which have been non-detachably connected to one another by roll-bonding and of which at least two steel layers have a different strength and/or elongation at fracture, heating the workpiece, and subjecting the workpiece to hot forming. To ensure a high strength and at the same time the easiest possible formability, the invention proposes that at least one section of the hot-formed workpiece is hardened, and that the workpiece is subsequently subjected to cold forming in the region in which the hardening has been performed. The invention also relates to a corresponding workpiece.