Patent ID: 7770682

Claim:
A pedal- and motor-assist power system for a bicycle which has, at least one drive wheel, and a bicycle frame with front and rear ends, said system comprising: a) a pedal section comprising: i. first and second pedal members; ii. a crank shaft connecting the pedal members; iii. a crank housing in which the crank shaft is located; b) a sprocket section having a chain-and-sprocket drive connection to said drive wheel; c) a motor section; d) a speed-reducing drive section connecting to said motor section and having a drive output; e) a power-assist drive section comprising a power assist drive member concentrically mounted around said crank shaft and having a power-assist drive connection between the drive section drive output and the sprocket section; f) said system being characterized in that the sprocket section has a first pedal overrunning drive connection with said pedal section and the power-assist drive connection has a second overrunning drive connection; whereby said bicycle is able to operate in four operating modes, namely: i. a power-assist mode where a bicycle rider is pedaling to supply power, and the power-assist section is providing power; ii. a pedal-only mode where power is being supplied solely by pedaling the bicycle; iii. the power-assist-only mode where the bicycle rider is not providing power by pedaling, but power is supplied by the power output section; iv. a coasting no-power mode where the bicycle is traveling with the pedal section stationary, and no power is being supplied by either the pedal section or the power-assist drive section, and g) said power-assist drive member having a tubular configuration with first and second power-assist member portions on opposite sides of the bicycle, said power-assist drive member and said crank housing being positioned concentrically around a center axis of said crank shaft; and h) said power-assist drive section comprising a length adjustable power-assist drive section comprising a power-assist mid-section positioned between said first and second power power-assist portions, and power-assist position adjustment member mounted to the power-assist mid-section so as to be movable to different positions along the power-assist mid-section in a manner that the distance between the two first and second power-assist portions, are adjustably spaced apart whereby the power-assist system could be used in bicycles having different width dimensions in a drive-section of the bicycle.