Patents by Inventor Robert W. Engstrom

Robert W. Engstrom 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: 7882907
    Abstract: The earth boring bit 10 is designed to bore an angular non-vertical hole into underlying strata. The bit 10 includes a plurality of steeply inclined cutting faces or edges 22 that define a relatively narrow included angle A therebetween. The bit's design ensures that the apex of the bit 10 will contact the surface S and/or other hard strata before the radially outwardly disposed gauge portion of the bit 10. This design reduces or obviates drill chattering or “walking” when the bit 10 is used to drill a hole at an angle that is not vertical relative to the surface or strata S. The bit 10 also includes an interchangeable flow control restrictor that optimizes the velocity of fluid pumped through the bit 10 and thus efficiently flushes debris from the hole as the hole is being drilled.
    Type: Grant
    Filed: October 11, 2007
    Date of Patent: February 8, 2011
    Inventor: Robert W. Engstrom
  • Publication number: 20100230175
    Abstract: The earth boring bit 10 is designed to bore an angular non-vertical hole into underlying strata. The bit 10 includes a plurality of steeply inclined cutting faces or edges 22 that define a relatively narrow included angle A therebetween. The bit's design ensures that the apex of the bit 10 will contact the surface S and/or other hard strata before the radially outwardly disposed gauge portion of the bit 10. This design reduces or obviates drill chattering or “walking” when the bit 10 is used to drill a hole at an angle that is not vertical relative to the surface or strata S. The bit 10 also includes an interchangeable flow control restrictor that optimizes the velocity of fluid pumped through the bit 10 and thus efficiently flushes debris from the hole as the hole is being drilled.
    Type: Application
    Filed: October 11, 2007
    Publication date: September 16, 2010
    Inventor: Robert W. Engstrom
  • Patent number: 5735360
    Abstract: A rotary mining bit is particularly suitable for use in the drilling of blasting holes in the mining industry, but may also be used for drilling wells and the like in both soft materials and hard, rocky materials. The bit comprises a central hollow body with a plurality of wings extending outwardly therefrom, with each wing having a leading edge with a plurality of cutting tooth sockets disposed therealong and each of the sockets having a cutting tooth affixed therein. The outermost cutting teeth on each wing describe a gauge row diameter, which defines the diameter of a hole formed using the present bit. The outermost cutting teeth are each angled outwardly, away from the axis of the bit and lateral edge of the wing. An inner or apex row of teeth describes a smaller cutting circle diameter, with intermediate teeth on each row preferably being irregularly spaced between the outermost and innermost teeth on each respective wing, so each intermediate tooth describes a different diameter circle from the others.
    Type: Grant
    Filed: November 12, 1996
    Date of Patent: April 7, 1998
    Inventor: Robert W. Engstrom