Patents Assigned to Marshalltown Trowel Company
  • Patent number: 6138318
    Abstract: A groover comprising a blade and a handle. The blade is a unitary member composed of and die cast from a zinc alloy. Smooth surface geometry provides for easy cleaning of the groover.
    Type: Grant
    Filed: November 6, 1998
    Date of Patent: October 31, 2000
    Assignee: Marshalltown Trowel Company
    Inventors: Georgia Pyatt, Jack D. Murders
  • Patent number: 6105882
    Abstract: An orifice plate for a texture material applicator having a number of nozzle orifices of differing diameters. Each nozzle orifice is defined by a nozzle extending normally from the plate in the direction of texture material flow. The length of each nozzle is the sum of the thickness of the plate plus the extent of the nozzle beyond the plate. The total length of each nozzle is proportional to its exit diameter.
    Type: Grant
    Filed: November 25, 1998
    Date of Patent: August 22, 2000
    Assignee: Marshalltown Trowel Company
    Inventor: Duane W. Woltjen
  • Patent number: 6032320
    Abstract: A trowel and related method of manufacture in which residual stresses are intentionally imposed upon the bottom working surface and/or the top mounting surface of a trowel blade. Stresses can be imposed, for example, by glass bead peening, shot peening, rolling, and/or brushing the metal trowel blade. Stresses are built up to a working stress level that remains substantially constant with further use of the trowel against abrasive, spreadable surfaces. Imposed stresses on the top and bottom surfaces can also be used to vary the resulting curvature of the blade.
    Type: Grant
    Filed: March 31, 1998
    Date of Patent: March 7, 2000
    Assignee: Marshalltown Trowel Company
    Inventors: Larry J. McComber, Jack D. Murders
  • Patent number: 5791009
    Abstract: A trowel and related method of manufacture in which residual stresses are intentionally imposed upon the bottom working surface and/or the top mounting surface of a trowel blade. Stresses can be imposed, for example, by glass bead peening, shot peening, rolling, and/or brushing the metal trowel blade. Stresses are built up to a working stess level that remains substantially constant with further use of the trowel against abrasive, spreadable surfaces. Imposed stresses on the top and bottom surfaces can also be used to vary the resulting curvature of the blade.
    Type: Grant
    Filed: September 11, 1996
    Date of Patent: August 11, 1998
    Assignee: Marshalltown Trowel Company
    Inventors: Larry J. McComber, Jack D. Murders
  • Patent number: 5781956
    Abstract: A handle for a concrete float comprising a molded outer grip surface shot around a molded plastic core. Two identical components are engaged to form the plastic core. Each component has an interior rib structure and a mounting nose. The mounting nose has a cavity for receiving a screw and a flat mounting surface. The screw passes through the cavity and engages the threaded recesses of the float blade, fastening the handle to the blade.
    Type: Grant
    Filed: January 17, 1996
    Date of Patent: July 21, 1998
    Assignee: Marshalltown Trowel Company
    Inventors: Curtis Dwight Kelsay, Alan Jerome Ness
  • Patent number: 5737795
    Abstract: A bull float for working and finishing concrete and the like is provided. The bull float includes a blade. The blade has a first working surface for contacting the work to be troweled. The first working surface has a leading edge and a trailing edge. The blade also has a leading edge member disposed at the leading edge and carries a second working surface disposed at an angle to the first working surface. The blade further includes a trailing edge member disposed at the trailing edge and carries a third working surface disposed at an angle to the first working surface. The bull float includes a planar metal sheet having a front edge and a rear edge, and having its mid area bowed outwardly relative to the working surface. The front and rear edge of the sheet are secured at points fixed with respect to the leading edge and the trailing edge.
    Type: Grant
    Filed: January 10, 1997
    Date of Patent: April 14, 1998
    Assignee: Marshalltown Trowel Company
    Inventor: Jack D. Murders
  • Patent number: 5713096
    Abstract: A finishing trowel comprised of a blade, a mounting and a handle, wherein the handle is hollow and has a square mounting hole for receiving a square mounting surface. A plastic handle is comprised of a durable inner core material and a grippable outer member. The handle's inner core includes deformable ribs which axially line the mounting hole and provide a secure, lash-free fit onto the mounting surface over a broader range of manufacturing tolerances for the parts. The handle also includes an endcap which cuts into and seals the endcap against an outer grippable material upon tightening of a flanged nut onto the mounting. A lip extends from the handle and encompasses a portion of the mounting to facilitate increased torque transfer from the handle to the mounting and blade. The replaceable handle can also be formed of other grippable materials such as wood.
    Type: Grant
    Filed: June 3, 1996
    Date of Patent: February 3, 1998
    Assignee: Marshalltown Trowel Company
    Inventors: Curtis Dwight Kelsay, Duane Walker Woltjen, Kent Douglas Williams
  • Patent number: 5615445
    Abstract: A taping knife which includes a blade with an elongated handle secured to the blade. The plastic handle includes a durable inner member and a grippable outer core. The hollow inner member is formed from adjoining member halves which have an inner structural support network of ribs. The handle component parts sealably interlock and are secured together upon formation of the outer grippable core whose material flows into certain ribbed network compartments and secures the interlocking parts together.
    Type: Grant
    Filed: December 27, 1994
    Date of Patent: April 1, 1997
    Assignee: Marshalltown Trowel Company
    Inventors: Curtis D. Kelsay, Alan J. Ness
  • Patent number: 5522111
    Abstract: A finishing trowel comprised of a blade, a mounting and a handle, wherein the handle is hollow and has a square mounting hole for receiving a square mounting surface. A plastic handle is comprised of a durable inner core material and a grippable outer member. The handle's inner core includes deformable ribs which axially line the mounting hole and provide a secure, lash-free fit onto the mounting surface over a broader range of manufacturing tolerances for the parts. The handle also includes an endcap which cuts into and seals the endcap against an outer grippable material upon tightening of a flanged nut onto the mounting. A lip extends from the handle and encompasses a portion of the mounting to facilitate increased torque transfer from the handle to the mounting and blade. The replaceable handle can also be formed of other grippable materials such as wood.
    Type: Grant
    Filed: December 8, 1994
    Date of Patent: June 4, 1996
    Assignee: Marshalltown Trowel Company
    Inventors: Curtis D. Kelsay, Duane W. Woltjen, Kent D. Williams
  • Patent number: 5446941
    Abstract: A trowel handle is injection molded from two separate types of plastic. An inner core is molded together with a finger guard from a plastic providing a smooth surface of a first coefficient of friction with the user's hand. The finger guard covers the metal tang of the trowel and protects the user's forefinger and thumb during troweling. An outergrip is molded from a thermoplastic rubber providing a soft, rubber-like surface of a second coefficient of friction with the user's hand.
    Type: Grant
    Filed: July 11, 1994
    Date of Patent: September 5, 1995
    Assignee: Marshalltown Trowel Company
    Inventor: Curtis D. Kelsay
  • Patent number: 5327612
    Abstract: A trowel handle is injection molded from two separate types of plastic. An inner core is molded together with a finger guard from a plastic providing a smooth surface of a first coefficient of friction with the user's hand. The finger guard covers the metal tang of the trowel and protects the user's forefinger and thumb during troweling. An outergrip is molded from a thermoplastic rubber providing a soft, rubber-like surface of a second coefficient of friction with the user's hand.
    Type: Grant
    Filed: March 2, 1993
    Date of Patent: July 12, 1994
    Assignee: Marshalltown Trowel Company
    Inventor: Curtis D. Kelsay