Patents Represented by Law Firm Brown & Wood
  • Patent number: 5988964
    Abstract: A drive-in dowel including an inner sleeve (2) having a load application element (3), a cone-shaped widening section (5) formed at a front, in a setting direction (S), end of the inner sleeve (2), and a substantially cylindrical support section (6) adjoining the cone-shaped widening section (5) and having an outer diameter (w) which is smaller than a largest diameter (d) of the cone-shaped widening section (5), and an outer sleeve (7) arranged coaxially with the inner sleeve (2) and having, in its front, in the setting direction (s), region, a plurality of expansion tabs (8) separated from each other by longitudinal slots and radially expandable upon the outer sleeve (7) being impact driven over the cone-shaped widening section (5) of the inner sleeve (2), with the expansion tabs (8) being provided with annularly arranged, chisel-like cutters (11).
    Type: Grant
    Filed: September 23, 1998
    Date of Patent: November 23, 1999
    Assignee: Hilti Aktiengesellschaft
    Inventors: Reinhard Lins, Erich Wisser, Helmut Gassner, Susanne Kossian, Michael Werner
  • Patent number: 5975217
    Abstract: A tool for drilling and/or chiseling has a striking mechanism (6) within a guide tube (9) for reciprocating a first piston (7) and, via an air cushion, for reciprocating a second piston (19) within the guide tube. The second piston drives a driving anvil (17) in the driving direction. Between the first and second pistons (7, 19) the guide tube (9) has a series of radially extending first air passages (10) arranged in a first plane (E1) extending perpendicularly of the driving direction. A control body can be shifted over the guide tube (9) and is connected to the driving anvil (17). The guide tube (9) has a second series of radially extending second air passages (11) therethrough arranged in a second plane (E2) spaced from the first plane (E1) at a distance (A) opposite to the driving direction.
    Type: Grant
    Filed: April 7, 1998
    Date of Patent: November 2, 1999
    Assignee: Hilti Aktiengesellschaft
    Inventors: Jens Frenzel, Helmut Nussrainer, Reinhard Schulz, Hans-Werner Bongers-Ambrosius