Rim for a spoked bicycle rear wheel
OwnerJiri Kramperainventor
Life of this patent
Estimating the term…
Abstract
A rim for a spoked bicycle rear wheel has rim holes laterally displaced by an amount (E) from an axis passing through the center of the cross-section of the rim. Such a rim can be subject to undesired tilting under stress imposed by spokes connected between the rim and the wheel hub and placed under tension. The rim side containing the spoke nipples is more highly loaded. To bring about balance of the tensions on both rim sides, the rim cross-section has an asymmetrical shape so that there is more rim material on the more highly loaded side and so that that side is also stiffer. The compressive forces in the rim material are better balanced, making it possible to use less expensive, conventional materials.
Claims19
A rim for a spoked bicycle rear wheel comprising
- a generally annular rim having an axis, two rim edges and a central plane (M) substantially perpendicular to the axis;
- means defining a plurality of spoke anchoring points distributed around said rim for attachment to one end of each of a plurality of spokes the other ends of which are connectable to a wheel hub, said anchoring points having an average axial position defining a second plane (N) axially offset from said central plane;
- said rim being shaped and dimensioned such that said rim has
- a first cross-sectional configuration before said rim is subjected to tensile forces through spokes attached to said anchoring points in which said rim is asymmetrical relative to said central plane and said rim edges have different external diameters, and
- a second cross-sectional configuration after said rim is subjected to said tensile forces in which said rim can be either asymmetrical or symmetrical relative to said central plane and in either case, in said second cross-sectional configuration, said rim edges have substantially the same external diameters.
A rim for a spoked bicycle rear wheel comprising
- a generally annular rim having an axis of rotation, two rim edges and a central plane substantially perpendicular to the axis;
- means defining a plurality of spoke anchoring points distributed around said rim, each for attachment to an end of one of a plurality of spokes the other ends of which are connectable to a wheel hub, said anchoring points having an average axial position defining a second plane axially offset from said central plane;
- said rim having a first portion located on one side of said central plane and including a first set of walls having a first rim edge and said anchoring points;
- said rim having a second portion located on the other side of said central plane and including a second set of walls having a second rim edge, said first and second portions being non-symmetrically shaped, said second set of walls having cross-sections smaller than cross-sections of said first set of walls;
- said rim having a first cross-sectional configuration before said rim is subjected to tensile forces transmitted through spokes attached to said anchoring points wherein the diameters of said first and second rim edges are substantially equal;
- and
- said rim having a second cross-sectional configuration after said rim is subjected to tensile forces transmitted through said spokes attached to said anchoring points wherein the diameters of said first and second rim edges are substantially equal.
Dependencies are inferred from the claim text.