Patents by Inventor Hsueh-Er Chang

Hsueh-Er Chang 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).

  • Stair-climbing vehicle
    Publication number: 20080164665
    Abstract: A vehicle for carrying object can overcome stairs and special geography. Rotators having wheels with of without auxiliary wheel are used. Various combinations of rotators and auxiliary wheel are possible.
    Type: Application
    Filed: January 5, 2007
    Publication date: July 10, 2008
    Inventor: Hsueh-Er Chang
  • Wheel apparatus
    Publication number: 20080018166
    Abstract: A wheel is designed to overcome special ground surfaces, like stairs. A carrying device can be equipped with at least one of such wheel so that a user can haul the carrying device to pass through special ground surfaces, like stairs, with ease and smoothness.
    Type: Application
    Filed: July 21, 2006
    Publication date: January 24, 2008
    Applicant: HSUEH-ER CHANG
    Inventor: Hsueh-Er Chang