US 9,808,869 B2
Hole cutter with chip egress aperture
Joseph Thomas Novak, East Longmeadow, MA (US); and Matthew Christopher Green, Amherst, MA (US)
Assigned to IRWIN INDUSTRIAL TOOL COMPANY, Huntersville, NC (US)
Filed by Joseph Thomas Novak, East Longmeadow, MA (US); and Matthew Christopher Green, Amherst, MA (US)
Filed on Jan. 13, 2010, as Appl. No. 12/687,078.
Prior Publication US 2011/0170971 A1, Jul. 14, 2011
This patent is subject to a terminal disclaimer.
Int. Cl. B23B 51/04 (2006.01)
CPC B23B 51/0406 (2013.01) [B23B 51/04 (2013.01); B23B 51/0453 (2013.01); Y10T 408/896 (2015.01); Y10T 408/8953 (2015.01)] 20 Claims
OG exemplary drawing
 
1. A hole cutter for cutting a work piece, comprising a substantially cylindrical blade body defining a blade body circumference, a cutting edge formed on one end of the blade body, and an axially-elongated slot formed through the substantially cylindrical blade body and configured to receive chips flowing from the cutting edge within an interior of the blade body and at least one of (i) into the slot, and (ii) through the slot, to prevent the collection of such chips within at least one of the interior of the blade body and an interface between the blade body and the work piece, wherein the substantially cylindrical blade body includes at least one protrusion formed along a side edge of the axially-elongated slot such that the axially-elongated slot includes at least one fulcrum extending therein, wherein the axially-longated slot defines a first end adjacent to the cutting edge and axially spaced therefrom a first distance selected to be within the range of about 15/100 inch to about ⅜ inch, a second end axially spaced from the cutting edge a second distance that is greater than the first distance and selected to be at least about one inch, and a slot area, wherein one of (i) the substantially cylindrical blade body defines a diameter of about 13/16 inch or less, only one of the axially-elongated slots is formed through the blade body, and a slot area to blade body circumference ratio is selected to be at least about 0.15; (ii) the substantially cylindrical blade body defines a diameter within the range of about ⅞ inch to about 1-7/16 inches, only two of the axially-elongated slots are formed through the blade body and angularly spaced relative to each other, and a slot area to blade body circumference ratio is selected to be at least about 0.18; (iii) the substantially cylindrical blade body defines a diameter within the range of about 1-½ inches to about 3-⅜ inches, at least two of the axially-elongated slots are formed through the blade body and angularly spaced relative to each other, and a slot area to blade body circumference ratio is selected to be at least about 0.1; and (iv) the substantially cylindrical blade body defines a diameter of about 3-1/2 inches or greater, more than two of the axially-elongated slots are formed through the blade body and angularly spaced relative to each other, and a slot area to blade body circumference ratio is selected to be at least about 0.1.