Patent ID: 7121394
Filing Date: 2006-10-17
Classification: F16D

Abstract:
1. A hub assembly for a bicycle which has a hub axle, comprising: a hub shell which is adapted to be mounted on and rotatable relative to the hub axle about an axis, and which has an inner tubular wall surface that is adapted to be spaced apart from the hub axle so as to define an annular accommodation space therebetween, that extends along the axis, and that terminates at an inner periphery, said inner tubular wall surface having a plurality of retreat bores which are angularly displaced from one another about the axis, which are disposed proximate to said inner periphery, and which respectively extend outwardly and radially; a spoke-mounting member including a tubular mount which extends from said inner periphery outwardly and radially, and which has a plurality of access openings that are angularly displaced from one another around the axis and that respectively extend along the axis to be communicated with corresponding ones of said retreat bores, respectively; a plurality of pawls disposed respectively in said retreat bores, and movable between a driven position, where said pawls extend radially into said annular accommodation space, and an idle position, where said pawls retreat radially into said retreat bores; a flywheel mounting cylinder which is adapted to be rotatably mounted on the hub axle, and which has a tubular coupling wall that confronts said tubular mount; and an annular drive member including a coupling segment which is coupled to be rotated with said tubular coupling wall, and a toothed segment which is opposite to said coupling segment along the axis and which extends into said annular accommodation space to confront said pawls radially, said toothed segment being coupled with said pawls to form a uni-directional mechanism that enables transmission of drive when said toothed segment engages said pawls in the driven position to thereby drive said hub shell to rotate in a clockwise direction, and that disenables the transmission of drive when said toothed segment passes over said pawls by forcing said pawls to the idle position to thereby enable said hub shell to remain unmoved in a counterclockwise direction.