| 摘要 |
<p>A crank axle unit mounted in a bottom bracket (5) assembled to a bicycle frame, which crank axle unit has a tubular element (2) surrounding and rotatably supporting a crank axle (1), the tubular element being surrounded by the bottom bracket(5), and a first screw ring (3) and a second screw ring (4) screwed into opposite ends of the bottom bracket (5) for positioning and fixing the tubular element (2) in the bottom bracket (5). The first screw ring (3) is fitted on an outside wall in one end region of the tubular element, and includes a threaded portion (3b) for screwing to an inside wall in one end region of the bottom bracket, and tool engaging teeth (10a) provided on an inside wall at an outward end of the first screw ring. The second screw ring (4) is fitted on an outside wall in the other end region of the tubular element, and includes a threaded portion (4a) for screwing to an inside wall in the other end region of the bottom bracket, and tool engaging teeth (11a) provided on an inside wall at an outer end of the second screw ring. The engaging teeth of the two screw rings are arranged at different pitches, but are engageable with the same tool (12a). <IMAGE></p> |
