The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 04, 1978
Filed:
Nov. 01, 1976
Clive Waddington, Stratford, CT (US);
Avco Corporation, Stratford, CT (US);
Abstract
An improved Waddington drive, employed here as a bicycle wheel hub, provides an automatically shifting transmission driven by an operator's foot pedal crank. A number of planet gears journaled for rotation in the hub engage and revolve around a fixed sungear on a mounting shaft thereby carrying and rotating the hub with them. The planet gears are connected through one-way clutches to cranks whose arms follow a cylindrical cam, the eccentricity of which is variable as a function of speed and torque. The cam is pivotally mounted from the rotating input shaft and its eccentricity is controlled by the reaction force between the cam and its followers, the centrifugal force on the cam, and a restoring force developed by a cantilever spring urging the cam to return to an initial eccentricity selectable to match the operator's capabilities. The centrifugal control force is developed by a flyweight integral with the cam and by a counterweight serving to dynamically balance the input shaft.