Double swingarm front suspension for bicycles and motorcycles
OwnerHorst Leitnerinventor
Life of this patent
Estimating the term…
Abstract
A suspension system for the front wheel of a bicycle or motorcycle, which has a minimum amount of friction. The suspension system includes an upper and a lower swingarm, with a spring and elastomer combination, which works as a friction damper on the inside coils on the spring. The relative angle and length of the swingarm to one another, permits the linear movement of the wheel on impact, to optimize suspension performance. The invention also desirably incorporates various elements which provide for the structural rigidity of the suspension assembly and light weight. In particular, the design preferably incorporates standard bicycle or motorcycle components. For example such components may include wheels, brakes, axles and steering components.
Claims12
A suspension system for a bicycle having a frame, a steering shaft defining a steering axis secured to and pivotable relative to said frame, and a front wheel defining an axle, comprising:
- a support member secured to said steering shaft;
- a fork defining a pair of generally straight parallel fork arms having an upper end and a bottom end, each of said pair of fork arms defining an axis, said bottom end of said fork retaining said axle of said front wheel;
- a top arm pivotably secured to said support member proximate said steering shaft and pivotably secured to said upper end of said fork;
- a lower arm comprising a single piece straddling said front wheel, said lower arm pivotably secured to and straddling said support member distal said top arm from said steering shaft, and pivotally secured to said upper end of said fork at a position spaced toward said bottom end of said fork from said top arm;
- means for resisting movement of said lower arm toward said steering shaft, wherein said top arm and said lower arm have different lengths and are nonparallel with respect to one another such that said bottom end of said fork arms moves linearly in response to impact transmitted through said front wheel.
A suspension system for a bicycle having a frame, a steering shaft defining a steering axis secured to and pivotable relative to said frame, and a front wheel defining an axle, comprising:
- a support member secured to said steering shaft;
- a fork defining a pair of generally parallel fork arms having an upper end and a bottom end, said bottom end of said fork retaining said axle of said front wheel;
- a top arm, said top arm pivotably secured to said support member proximate said steering shaft and pivotably secured to said upper end of said fork;
- a lower arm comprising a single piece having a top end pivotably secured to and straddling said support member distal said top arm from said steering shaft and a bottom end straddling said front wheel pivotally secured to said top end of said fork at a position spaced toward said bottom end of said fork from said top arm;
- a biasing member secured between said support member and said lower arm, wherein said top arm and said lower arm have different lengths and are nonparallel with respect to one another such that said bottom end of said fork arms moves substantially linearly in response to impact transmitted through said front wheel and, when said suspension is fully compressed, said bottom end of said lower arm is positioned proximate said steering shaft.
A suspension system for a bicycle having a frame, a steering shaft defining a steering axis secured to and pivotable relative to said frame, and a front wheel defining an axle, comprising:
- a fork defining a pair of generally parallel fork arms having an upper end and a bottom end, said bottom end of said fork retaining said axle of said front wheel;
- a mechanism, comprising:
- a support member secured to said steering shaft;
- a top arm pivotably secured to said support member proximate said steering shaft and pivotably secured to said upper end of said fork;
- a lower arm comprising a single piece having a top end pivotably secured to said support member distal said top arm from said steering shaft, said lower arm further defining a bottom end pivotally secured to said top end of said fork at a position spaced toward said bottom end of said fork from said top arm;
- a biasing member secured between said support member and said lower arm,
- wherein said top arm and said lower arm have different lengths and are nonparallel with respect to one another such that said bottom end of said fork arm moves substantially linearly in response to impact transmitted through said front wheel, said mechanism is located below substantially the entire steering shaft and, when said suspension is fully uncompressed, substantially the entire mechanism is positioned above said wheel.
A suspension system for a bicycle having a frame, a steering shaft defining a steering axis secured to and pivotable relative to said frame, and a front wheel defining an axle, comprising:
- a fork defining a pair of generally straight parallel fork arms having an upper end and a bottom end, each of said pair of fork arms defining an axis, said bottom end of said fork retaining said axle of said front wheel;
- a mechanism, comprising:
- a support member secured to said steering shaft;
- a top arm pivotably secured to said support member proximate said steering shaft and pivotably secured to said upper end of said fork;
- a lower arm comprising a single piece pivotably secured to said support member distal said top arm from said steering shaft and pivotally secured to said upper end of said fork at a position spaced toward said bottom end of said fork from said top arm;
- means for resisting movement of said lower arm toward said steering shaft,
- wherein said top arm and said lower arm have different lengths and are nonparallel with respect to one another such that said bottom end of said fork arms move substantially linearly in response to impact transmitted through said front wheel, said mechanism is located below substantially the entire steering shaft and, when said suspension is fully compressed, said bottom end of said lower arm is positioned proximate said steering shaft, and wherein further, when said suspension is fully uncompressed, substantially the entire mechanism is positioned above said wheel.
Dependencies are inferred from the claim text.