Patents by Inventor Tollief O. Hillestad

Tollief O. Hillestad 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).

  • Patent number: 5582538
    Abstract: A portable tube cutting apparatus which facilitates smooth, even cuts through a boiler tube-wall includes a frame supporting a movable carriage, a motor driven cutting tool secured to the carriage, and an articulated support means which allows for rotation of the cutting apparatus about a fixed point of securement to the boiler tube-wall and thereby permits lateral repositioning of the cutting apparatus relative to the point of securement to the boiler tube-wall. The apparatus has the advantage of permitting relatively long cuts such as up to about 3 feet to be made in a tube-wall While reducing the amount of time and effort needed to install and set up such apparatus relative to conventional track mounted apparatuses.
    Type: Grant
    Filed: April 4, 1994
    Date of Patent: December 10, 1996
    Inventor: Tollief O. Hillestad
  • Patent number: 5199221
    Abstract: A portable tube cutting apparatus which facilitates smooth even cuts. The apparatus has a frame supporting a movable carriage, a motor driven cutting tool secured to the carriage, and vise-like fasteners for supporting the frame from a stationary object, such as the tube which is to be cut. A pair of spaced parallel rods, secured to the frame, pass through a pair of corresponding cylindrically bored guides attached to the carriage to restrict movement of the carriage to a linear path which passes through the tube which is to be cut while the apparatus is being used. A rack and pinion arrangement operably connected to a lever is preferably provided for smoothly advancing the carriage toward the tube.
    Type: Grant
    Filed: February 13, 1992
    Date of Patent: April 6, 1993
    Inventor: Tollief O. Hillestad
  • Patent number: 5033347
    Abstract: An apparatus for cutting boiler tubes comprising a movable carriage having a cutting means where the carriage and cutting means are supported on a lateral supporting beam secured adjacently to a bank of boiler tubes. The movable carriage means is stabilized with a plurality of bearings means for engaging the lateral beam and preventing strain and vibrations during the cutting process. The cutting means is preferably powered by a pneumatic motor.
    Type: Grant
    Filed: May 22, 1990
    Date of Patent: July 23, 1991
    Inventors: Tollief O. Hillestad, Mark W. Hillestad
  • Patent number: 5007778
    Abstract: A portable gas operated rotary tool is provided for milling a surface on the end of a cylindrical workpiece. The tool has a motor powered by a pressurized gas, such as compresseed air. The motor directly drives a rotary milling head which is axially aligned with the axis of rotation of the motor. The motor has a stator chamber which houses a rotor having radial slots. Vanes are journaled within said slots for radial movement within the slot and define progressively expanding cavities. The milling head has a central bore for mounting on an arbor of the motor. The milling head includes blades for milling a frustoconical surface on the workpiece and a non-locking pilot tube to align the tool with the longitudinal axis of the workpiece. An air motor design is also disclosed that provides very high rotary speeds using standard air system pressure, very high horsepower, a low polar amount of inertia and low torque.
    Type: Grant
    Filed: February 21, 1990
    Date of Patent: April 16, 1991
    Inventors: Tollief O. Hillestad, Mark W. Hillestad
  • Patent number: 4915552
    Abstract: A portable gas operated rotary tool is provided for milling a surface on the end of a cylindrical workpiece. The tool has a motor powered by a pressurized gas, such as compressed air. The motor directly drives a rotary milling head which is axially aligned with the axis of rotation of the motor. The motor has a stator chamber which houses a rotor having radial slots. Vanes are journaled within said slots for radial movement within the slot and define progressively expanding cavities. The milling head has a central bore for mounting on an arbor of the motor. The milling head includes blades for milling a frustoconical surface on the workpiece and a non-locking pilot tube to align the tool with the longitudinal axis of the workpiece. A novel air motor design is also disclosed that provides very high rotary speeds using standard air system pressure, very high horsepower, a low polar moment of inertia and a low torque.
    Type: Grant
    Filed: April 6, 1989
    Date of Patent: April 10, 1990
    Inventors: Tollief O. Hillestad, Mark W. Hillestad
  • Patent number: 4889454
    Abstract: A portable gas operated rotary tool is provided for milling a surface on the end of a cylindrical workpiece. The tool has a motor powered by a pressurized gas, such as compressed air. The motor directly drives a rotary milling head which is axially aligned with the axis of rotation of the motor. The motor has a stator chamber which houses a rotor having radial slots. Vanes are journaled within said slots for radial movement within the slot and define progressively expanding cavities. The milling head has a central bore for mounting on an arbor of the motor. The milling head includes blades for milling a frustonconical surface on the workpiece and means to align the tool with the longitudinal axis of the workpiece.
    Type: Grant
    Filed: October 7, 1988
    Date of Patent: December 26, 1989
    Inventors: Tollief O. Hillestad, Mark W. Hillestad
  • Patent number: 4761104
    Abstract: A portable milling tool for milling pipes, tubes, cylinders, and the like has an expandable sleeve at one end thereof for securing and centering the tool to a workpiece. An adjustable in-line rod connects the sleeve to the tool and permits the sleeve to release or secure the workpiece. An in-line shaft moves the tool into or out of engagement with the workpiece. The tool also is of compact design allowing it to be used in on-site situations wherein tool size is a problem as in milling boiler tubes.
    Type: Grant
    Filed: March 21, 1985
    Date of Patent: August 2, 1988
    Inventor: Tollief O. Hillestad
  • Patent number: 4620823
    Abstract: A portable milling tool for milling pipes, tubes, cylinders, and the like has a collet at one end thereof for securing and centering the tool to the work piece. An adjustable in-line rod connects the collet to the tool and permits the collet to secure or release the work piece. An in-line shaft moves the tool into or out of engagement with the work piece. The tool is of compact design allowing it to be used in on-site situations wherein tool size is a problem.
    Type: Grant
    Filed: July 29, 1982
    Date of Patent: November 4, 1986
    Inventor: Tollief O. Hillestad
  • Patent number: 4449871
    Abstract: This tool is for performing precise machine operations on boiler tube ends, while the tubes are in place in the boiler, and it consists primarily of a hand-held housing, including therein a main gear and pinion gear, designed specifically for strength and long life, the combination serving to rotate a cutting tool holder, having a multiple number of cutting blades. It further includes a self-contained air motor, for driving the cutting tool holder, so as to mill the outside diameters of the boiler tubes, and the tool also includes a collet and rod secured to its center shaft, for locking the tool in a boiler tube.
    Type: Grant
    Filed: December 8, 1980
    Date of Patent: May 22, 1984
    Inventor: Tollief O. Hillestad