Chain sprocket with opposite frangible side guide plates
OwnerEarnest D. Mosleyinventor
Life of this patent
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Abstract
A chain sprocket having guide plates comprising flanges of a frangible material located along opposite sides of the sprocket is disclosed teeth and projecting outwardly therefrom to prevent lateral disengagement of the chain under conditions of severe usage, particularly with use of the sprocket and chain assembly on a racing motorcycle. The guide plates are particularly useful in guiding the slack lower reach on of a motorcycle chain during acceleration of a motorcycle, and are also useful in guiding the slack upper reach of the chain during deceleration.
Claims10
A chain driven wheel sprocket for use in driving the rear wheel of a racing motorcycle wherein the sprocket is driven by a sprocket chain mechanically engageable therewith, and the sprocket is provided with opposite frangible side guide flanges having at least substantially parallel opposing flange guide surfaces for retaining therebetween the sprocket chain with a total lateral clearance between the guide surfaces and chain of from 0 to about 0.050 inches, said flange guide surfaces projecting outwardly beyond the chain at least the radial height of the chain and being constructed of a non-metallic frangible material having a minimum elastic limit such that breaking of the guide flange, rather than permanent deforming thereof, occurs under lateral impact or force, whereby continued operation of the chain and sprocket is not substantially impaired after occurrence of such lateral impact or force on the guide flange.
In combination, a sprocket member having peripheral teeth thereon, a sprocket chain engaging a portion of the periphery of the sprocket member for transfer of driving force therebetween, and frangible guide means disposed peripherally of the sprocket member to retain the sprocket chain in radial alignment with the teeth on the sprocket member, the guide means being a lightweight frangible non-metal and including a pair of guide flanges projecting radially outwardly of the teeth with the inner guide surfaces of the guide flanges being spaced axially of the teeth a distance to closely receive the sprocket chain when moving into and out of engagement with the teeth, the inner guide surfaces of the guide flanges extending radially outwardly of the teeth a distance to engage and guide the chain when adjacent the radial outer end of the teeth, the inner guide surfaces having an axial separation which provides a total lateral axial clearance between the inner guide surfaces and the chain of less than about 0.050 inches, whereby transverse displacement of the chain is reduced to no more than about 0.050 inches, and whereby the chain is cleaned in use, the frangible non-metal guide means having a minimum elastic limit such that breaking of the guide flange, rather than permanent deforming thereof, occurs under lateral impact or force, whereby continued operation of the chain and sprocket member is not substantially impaired after occurrence of such lateral impact or force on the guide flange.
Dependencies are inferred from the claim text.