Patents by Inventor H.ang.kan Engstrom

H.ang.kan Engstrom 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).

  • Rock drill having an internal flushing channel
    Patent number: 6102141
    Abstract: A rock drill for percussive drilling includes a shank, a collar connected to a front end of the shank, and a rod portion which at one end connects to the collar while the other end carries a rock cutting means. A central flush channel extends from the front free end of the shank in a direction towards the front end. The central flush channel has a substantially constant diameter (d) along essentially its entire length; a ratio of the diameter (d) to a smallest outer cross sectional width (D) of the rod portion being in the range of 0.35 to 0.43.
    Type: Grant
    Filed: September 8, 1998
    Date of Patent: August 15, 2000
    Assignee: Sandvik AB
    Inventors: H.ang.kan Engstrom, Jan-Gunnar Hedlund, Goran Palmberg