Patents by Inventor Qingzhu Mao

Qingzhu Mao 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: 6251036
    Abstract: A carbon fiber arrow shaft comprises a hollow tube, a reinforced carbon fiber, and a resinoid binder. The hollow tube has a length between 500-900 mm, an inner diameter between 2-10 mm, and a tube wall thickness between 0.3-2 mm. The reinforced carbon fiber and the resinoid binder form a resin-impregnated carbon fiber. The carbon fiber arrow shaft is formed by directly and continuously winding the resin-impregnated carbon fiber around the hollow tube. The carbon fiber arrow shaft has a head section (L1), a middle section (L2) and a tail section (L3). A winding angle of the carbon fiber at the head section (L1) is changed from a larger winding angle to a smaller winding angle, a winding angle at the middle section (L2) stays constant, and a winding angle at the tail section (L3) is changed from a smaller winding angle to a larger winding angle. The lengths of the head section (L1) and the tail section (L3) are between 25-250 mm.
    Type: Grant
    Filed: March 1, 2000
    Date of Patent: June 26, 2001
    Assignee: Beijing Institute of Aeronautical Materials
    Inventors: Xiang Wu, Qingzhu Mao, Wenhao Chen, Dahai Sun, Minyong Liu, Weifang Chen