Patents by Inventor David G. Doan

David G. Doan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5501478
    Abstract: An occupant propelled three wheeled vehicle, e.g., a tricycle, includes a frame, a seat, a front driven wheel, two laterally spaced steerable rear wheels and handlebar steering mechanism. The front wheel is driven via a gear and chain arrangement by a pedal assembly which is located at least partially rearwardly of the front wheel axis. The handlebar steering mechanism is located forward of the seat and controls the steering of the rear wheels by simultaneously rotating each rear wheel about a respective vertical axis. The handlebar steering mechanism includes levers which independently control the braking of the two rear wheels and the front wheel. The handlebar steering mechanism also includes a gear shift lever permitting the user to selectively choose a desired gearing ratio between the pedal assembly and the front drive wheel. The seat is positioned with respect to the pedal assembly for substantially upright pedalling, as opposed to recumbent pedalling.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: March 26, 1996
    Assignee: Robert L. Doan
    Inventor: David G. Doan