Bicycle crank assembly
AssigneeOcean State International, Inc.
InventorRobert H. Girvin
Life of this patent
Estimating the term…
Abstract
A bicycle crank assembly utilizing a hollow crank arm is disclosed. The crank arm is welded to a hub for mounting to an axle and reinforced using a doubler provided at a point of maximum stress to minimize the likelihood of breakage at the maximum stress point. The resulting bicycle crank assembly exhibits reduced weight without a substantial reduction of torsional or bending strength.
Claims19
A bicycle crank assembly comprising:
- a) a cylindrical hub;
- b) a crank arm having a proximal end and a distal end attached to the hub at its proximal end at a connecting junction, a portion of the junction being subject to maximum tensile stress when the crank arm is driving the hub so as to propel a bicycle in a forward direction;
- and
- c) a reinforcing member attached to both the crank arm and the hub, which member extends to a location on the crank arm more distal than the junction, and which member fully overlaps the junction at the portion subject to the maximum tensile stress.
In a bicycle crank assembly in which a crank arm is welded to a cylindrical hub, the improvement which comprises providing a reinforcing member on the assembly at an area of maximum stress between the hub and the crank arm.
Dependencies are inferred from the claim text.