Abstract: A rotatable sprocket assembly transmits force from a chain into rotation of a wheel on a bicycle. A plurality of sprocket segments having peripheral teeth are mounted on a pair of sprocket housings so that the combined periphery of the sprocket segments is substantially circular. The sprocket segments are slidable relative to the housing in a substantially radial direction so as to vary the diameter of the combined sprocket segments. Each sprocket segment is formed from a plurality of hinged subsegments, with each subsegment having a single tooth thereon. The sprocket segments of one housing overlap the adjacent sprocket segments on the other housing so that the pairs of overlapping teeth combine to effectively form a single tooth. The sprocket segments are movable angularly relative to the sprocket housings, so that in combination with the radial displacement of the sprocket segments, the total number of effective teeth on the sprocket assembly can be varied in increments of one tooth.
Type:
Grant
Filed:
October 14, 1988
Date of Patent:
August 28, 1990
Assignee:
Autra-Bike Co., Inc.
Inventors:
Keith C. Chilcote, Robert J. Malahowski
Abstract: An improved hydraulic brake apparatus for bicycles wherein brake pads are operably associated with both the front and rear wheels of the bicycle and manually actuated by a brake handle to enforce braking conditions. The improved brake apparatus includes an immersed valve member in a vertical hydraulic mechanism designed for simple and efficient performance, an improved linkage that provides increased mechanical advantage, self-adjusting retraction screws that allow for customary pad wear, an improved housing clamp for mounting the housing to the handlebar and an enhanced hose fitting that is likewise designed for simple, effective performance.
Abstract: A rotable sprocket assembly transmits force from a chain into rotation of a bicycle wheel. Sprocket segments having peripheral teeth are mounted on a pair of sprocket housings so that the combined periphery of the sprocket segments is substantially circular. The housings are stationary relative to each other and each is oriented in a plane which is normal to a central rotational axis. The sprocket segments are slidable relative to the housing in a radial direction so as to vary the diameter of the combined sprocket segments. Each sprocket segment is formed from a plurality of hinged subsegments, with each subsegment having a single tooth. The sprocket segments of one housing overlap the adjacent sprocket segments on the other housing so that the pairs of overlapping teeth combine to effectively form a single tooth.