Patents by Inventor Jan-Erik Sundstrom

Jan-Erik Sundstrom 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).

  • Method, drilling tool and rock drill bit for transferring impact energy from a top hammer unit
    Patent number: 6021855
    Abstract: The present invention relates to a drilling tool for percussive drilling by means of a top hammer unit, which unit gives compressive pulses. The tool comprises at least one drill tube (12) and a drill bit (11), which cooperates via a connection. The drill bit comprises a bit head (13) provided with crushing means (15) and a shank (17). A shoulder (20) is provided in connection with the bit head, said bit portion having a first abutment surface (21) facing towards a free end of the tube. The free end of the tube facing towards the drill bit is povided with a second abutment surface (23), said top hammer unit being provided to tannsfer compressive pulses to the tube. Each compressive pulse is transferred to the drill bit via the impact surfaces (21, 23). The tube and the drill bit comprise cooperating device (19, 24, 25) for driving and retaining. The tool is defined by that it has a relation between the length of the shank and the length of the bit head that is 5 or more.
    Type: Grant
    Filed: May 6, 1998
    Date of Patent: February 8, 2000
    Assignee: Sandvik AB
    Inventors: Rainer Beccu, Per-Olof Liljebrand, Urban Olsson, Jan-Erik Sundstrom