Patents by Inventor Niels Halfdan Boa

Niels Halfdan Boa 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).

  • Hammer drilling devices
    Patent number: 4047722
    Abstract: In a drilling device, especially a hammer drill, a tool is coupled to a tool receiving means by co-operating male and female coupling elements which ensure uniform rotational motion of the tool in relation to the tool receiving means; additional transition and guiding surfaces being provided for inserting or removing the tool single-handed.
    Type: Grant
    Filed: August 19, 1975
    Date of Patent: September 13, 1977
    Assignee: H. Reinholdt A/S
    Inventors: Mogens B. Nielsen, Niels Halfdan Boa, Jimmy Jensen