| 摘要 |
<p>A bicycle bottom bracket (10) for mounting a cartridge bottom bracket unit (34) comprising a sleeve (39) in which a crankshaft (35) is mounted by means of a bearing. One end of the sleeve (39) has a taper (55) and protrusions (50) which engage with a complementary taper (56) and grooves (51) in a lug (16a) of the bottom bracket (10). A fixing nut (57) which may have a tapered exterior (58) screws onto male threads (46) on one end of the sleeve (39) to draw the complementary tapers together. The protrusions may be omitted and the sleeve (39) screwed directly into female threads in the bottom bracket (10). The effects of deformation of female threads due to thermal deformation of the bottom bracket do not impair smooth rotation of the crankshaft and the tapping of one or both female threads in the bottom bracket may be omitted. More efficient assembly is thereby afforded. <IMAGE></p> |
