Patents by Inventor Kenneth L. Larsson

Kenneth L. Larsson 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).

  • Excavating tool cutting insert
    Patent number: 5161859
    Abstract: The invention relates to a tool for breaking or excavating of hard material, such as asphalt. The tool comprises a cutting insert (11) secured to a tool body (10). For purposes maintaining the required cutting force low while ensuring that the risk is low that the cutting insert (11) will get loose the cutting insert (11) is provided with a concave portion (17.sup.1) between the tip portion (12) of the cutting insert and a rear shoulder (13) thereon.
    Type: Grant
    Filed: May 30, 1991
    Date of Patent: November 10, 1992
    Assignee: Santrade Limited
    Inventors: Kenneth L. Larsson, Bert G. Levefelt
  • Drill string element
    Patent number: 4961469
    Abstract: A drill string element for use in top hammer percussive drilling comprises first and second tubes coupled together by a cylindrical thread, and at least one impact-transmitting ord slidably disposed in the tubes. The rod(s) includes abutments which engage restrictions formed at remote ends of the tubes whereby the rod(s) can be removed only by unscrewing the tubes from one another. Remote ends of the tubes define male and female conical threads which enable the element to be connected to similar elements in the forming of a drill string. The conical threads are easier to unscrew than the cylindrical threads to avoid an accidental separation of the tubes of each element when that element is being unscrewed from another element.
    Type: Grant
    Filed: April 24, 1989
    Date of Patent: October 9, 1990
    Assignee: Sandvik AB
    Inventors: Kenneth L. Larsson, Sven P. Liljebrand
  • Excavating tool cutting insert
    Patent number: 4938538
    Abstract: The invention relates to a tool for breaking or excavating hard material, such as asphalt. The tool comprises a cutting insert (11) secured to a tool body (10). For purposes of maintaining the required cutting force low while ensuring that the risk is low that the cutting insert (11) will get loose the cutting insert (11) is provided with a concave portion (17.sup.1) between the tip portion (12) of the cutting insert and a rear shoulder (13) thereon.
    Type: Grant
    Filed: March 6, 1984
    Date of Patent: July 3, 1990
    Assignee: Santrade Limited
    Inventors: Kenneth L. Larsson, Bert G. Levefelt
  • Threaded coupling
    Patent number: 4861209
    Abstract: A threaded coupling for a high frequency percussion drill assembly comprises a rod and a sleeve having external and internal threads, respectively. The threads are of the asymmetrical type and make contact along opposing shoulder portions disposed on only one side of each crown portion. The threads have a maximum diameter from 30 to 40 mm, a pitch of 7 to 11 mm, and a height from 1.2 to 1.6 mm. The parts of the root and crown portions located immediate adjacent the contacting shoulder portions have radii from 3 to 5 mm.
    Type: Grant
    Filed: July 14, 1987
    Date of Patent: August 29, 1989
    Assignee: Sandvik AB
    Inventor: Kenneth L. Larsson