Hole cutter with chip egress aperture

Patent metadata

Field	Value
Publication number	US-9782839-B2
Application number	US-201113006117-A
Country	US
Kind code	B2
Filing date	Jan 13, 2011
Priority date	Jan 13, 2010
Publication date	Oct 10, 2017
Grant date	Oct 10, 2017

Abstract

A hole cutter has 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. The axially-elongated slot is configured to receive chips flowing from the cutting edge within the interior of the blade body and (i) into the slot, and/or (ii) through the slot, to prevent the collection of such chips within the interior of the blade body and/or at an interface between the blade body and work piece. The axially-elongated slot defines a first end adjacent to the cutting edge, a second end axially spaced further from the cutting edge, and a slot area. The hole cutter further defines a total slot area to blade body circumference ratio within the range of about 0.1 to about 0.3 depending on the size of the hole cutter.

First claim

What is claimed is:

1. A hole cutter for cutting a work piece, comprising:
a substantially cylindrical blade body defining a blade body circumference,
an annular 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-elongated 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 0.13; (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 0.15; (iii) the substantially cylindrical blade body defines a diameter within the range of about 1½ inches to about 3⅜ 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 3½ 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.

2. A hole cutter as defined in claim 1 , wherein one of (i) the substantially cylindrical blade body defines a diameter of about 13/16 inch or less, and the axially-elongated slot defines a slot area to blade body circumference ratio within the range of about 0.13 to about 0.25; (ii) the substantially cylindrical blade body defines a diameter within the range of about ⅞ inch to about 1 7/16 inches, and the two axially-elongated slots define a slot area to blade body circumference ratio within the range of about 0.15 to about 0.33; (iii) the substantially cylindrical blade body defines a diameter within the range of about 1½ inches to about 3⅜ inches, and the at least two axially-elongated slots define a slot area to blade body circumference ratio within the range of about 0.1 to about 0.33; and (iv) the substantially cylindrical blade body defines a diameter of about 3½ inches or greater, and the more than two axially-elongated slots define a slot area to blade body circumference ratio within the range of about 0.1 to about 0.25.

3. A hole cutter as defined in claim 2 , wherein the hole cutter defines a direction of rotation that is the cutting direction of the cutting edge, and the first end of the axially-elongated slot defines a sloped edge surface that slopes away from the cutting edge in a direction opposite the cutting direction.

4. A hole cutter as defined in claim 3 , wherein the first end of the axially-elongated slot defines a maximum width of at least about ⅖ inch, the sloped edge surface is at least about ⅖ inch long, and the sloped edge surface is at least one of curvilinear and rectilinear.

5. A hole cutter as defined in claim 4 , wherein the sloped edge surface is oriented at an acute angle relative to an axis of the blade body within the range of about 35° to about 60°.

6. A hole cutter as defined in claim 2 , wherein the hole cutter defines a direction of rotation that is the cutting direction of the cutting edge, and the second end of the axially-elongated slot is angularly spaced relative to the first end of the axially-elongated slot in a direction opposite the cutting direction.

7. A hole cutter as defined in claim 6 , wherein the axially-elongated slot is oriented at an acute angle relative to an axis of the blade body.

8. A hole cutter as defined in claim 7 , wherein the acute angle is at least about 30°.

9. A hole cutter as defined in claim 8 , wherein the acute angle is within the range of about 35° to about 60°.

10. A hole cutter as defined in claim 1 , wherein the cutting edge is defined by a plurality of saw teeth including tips and gullets between the tips, and the first distance is measured from either (i) a deepest gullet of the cutting edge, or (ii) a plane extending between tips of unset teeth of the cutting edge.

11. A hole cutter as defined in claim 10 , wherein the second distance is at least about 1½ inches.

12. A hole cutter as defined in claim 1 , wherein the axially-elongated slot defines a minimum width of about 0.27 inch to allow insertion of a number 2 screwdriver therethrough.

13. A hole cutter as defined in claim 1 , wherein the cutting edge is bi-metal.

14. A hole cutter as defined in claim 1 , wherein one of (i) the diameter of the substantially cylindrical blade body is about 1 7/16 inches or less, and the axially-elongated slot is oriented substantially parallel to an axis of the blade body, and (ii) the diameter of the substantially cylindrical blade body is greater than about 1 7/16 inches, and each axially-elongated slot is oriented at an acute angle relative to an axis of the blade body and slopes away from the cutting edge in a direction opposite a cutting direction.

15. A hole cutter as defined in claim 1 , wherein the blade body defines a wall region extending annularly about the blade body, and extending axially between the cutting edge and the first end of the axially-elongated slot a distance within the range of about 15/100 inch to about ⅜ inch.

16. A hole cutter as defined in claim 1 , wherein the axially-elongated slot includes two fulcrums extending therein.

17. A hole cutter for cutting a work piece, comprising:
a substantially cylindrical blade body defining a blade body circumference,
an annular cutting edge formed on one end of the blade body, and
means formed through the substantially cylindrical blade body for receiving chips flowing from the cutting edge within an interior of the blade body and at least one of (i) into the means, and (ii) through the means, for preventing 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 means such that the means includes at least one fulcrum extending therein,
wherein the means 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 leas

Assignees

• Novak Joseph Thomas
• Green Matthew Christopher
• Irwin Ind Tool Co

Inventors

• Novak Joseph Thomas
• Green Matthew Christopher

Classifications

• Y10T408/896

  Having product-receiving chamber · CPC title

• B23B2260/072

  Grooves · CPC title

• Y10T408/895

  Having axial, core-receiving central portion · CPC title

• Y10T408/8953

  with lateral outlet · CPC title

• B23B51/04 Primary

  {Drills} for trepanning · CPC title