Patents by Inventor Hakan Krekula

Hakan Krekula 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).

  • Publication number: 20170298732
    Abstract: A rock bolt to be embedded in a borehole and a method of manufacturing a rock bolt, the rock bolt including an extended energy-absorbing part, the first end of the energy-absorbing part including an anchor and the second end of the energy-absorbing part including a screw joint for prestressing the rock bolt. The rock bolt includes an extended tubular part with a jacket and a first end section and a second end section, with an internal dimension that is larger than the external dimension of the energy-absorbing part and arranged in such a manner that it surrounds the energy-absorbing part.
    Type: Application
    Filed: September 22, 2015
    Publication date: October 19, 2017
    Applicant: Northern Mining Products AB
    Inventors: HÃ¥kan Krekula, Leif Eriksson
  • Patent number: 9051831
    Abstract: The present invention concerns a tubular rock bolt (1) that can be expanded by a pressurised medium, for insertion into a drilled hole (16) and comprising an extended tubular part (2) with a closed cross-section (12) and provided with a longitudinal stamped part (13) that increases in diameter during the expansion of the rock bolt (1) without the periphery of the tubular part (2) being bent, and an end section (17) at one end (15) of the rock bolt (1) and an end piece (19) arranged at the second end (18) of the rock bolt (1) and provided with a connection part (22) for interaction in a manner that can be released with an expansion means (23). The extended tubular part (2) comprises a reinforcement means (3) that extends internally inside the tubular part (2) between the end section (17) and the end piece (19) and that is attached at the end section (17) and the end piece (19). The invention concerns also the manufacture of a rock bolt.
    Type: Grant
    Filed: June 21, 2012
    Date of Patent: June 9, 2015
    Inventors: Hakan Krekula, Leif Eriksson
  • Publication number: 20140119839
    Abstract: The present invention concerns a tubular rock bolt (1) that can be expanded by a pressurised medium, for insertion into a drilled hole (16) and comprising an extended tubular part (2) with a closed cross-section (12) and provided with a longitudinal stamped part (13) that increases in diameter during the expansion of the rock bolt (1) without the periphery of the tubular part (2) being bent, and an end section (17) at one end (15) of the rock bolt (1) and an end piece (19) arranged at the second end (18) of the rock bolt (1) and provided with a connection part (22) for interaction in a manner that can be released with an expansion means (23). The extended tubular part (2) comprises a reinforcement means (3) that extends internally inside the tubular part (2) between the end section (17) and the end piece (19) and that is attached at the end section (17) and the end piece (19). The invention concerns also the manufacture of a rock bolt.
    Type: Application
    Filed: June 21, 2012
    Publication date: May 1, 2014
    Inventors: Hakan Krekula, Leif Eriksson