Hole cutter with multiple fulcrums

Patent metadata

Field	Value
Publication number	US-2020114435-A1
Application number	US-201916713221-A
Country	US
Kind code	A1
Filing date	Dec 13, 2019
Priority date	Jan 13, 2010
Publication date	Apr 16, 2020
Grant date	—

Abstract

A hole cutter has a cylindrical blade body including a cutting edge and one or more axially-elongated apertures formed within a side wall of the blade body. The axially-elongated aperture is configured to receive a lever, such as a screwdriver, therethrough. Each axially-elongated aperture includes a first fulcrum axially spaced adjacent to the cutting edge, a second fulcrum axially spaced further away from the cutting edge than the first fulcrum, and optionally a third fulcrum axially spaced between the first and second fulcrums. A lever, such as a screwdriver, can be inserted into the aperture and placed against each of the fulcrums to lever slugs out of the interior of the blade body.

First claim

What is claimed is:

1 . A hole cutter comprising:
a substantially cylindrical blade body defining a cutting edge and a longitudinal axis; and at least one elongated aperture formed through the blade body and spaced from the cutting edge such that a portion of the blade body extends between the cutting edge and the elongated aperture, the at least one elongated aperture having a first portion with a first fulcrum surface axially spaced from the cutting edge by a first distance, a second portion with a second fulcrum surface axially spaced from the cutting edge by a second distance greater than the first distance, and an intermediate portion oriented at an acute angle to the longitudinal axis of the blade body and connecting the first portion and the second portion; wherein the at least one elongated aperture is configured to receive therethrough a lever for removing a work piece slug from an interior of the blade body, the lever configured to engage the first fulcrum surface to lever the slug at least partially out of the interior of the blade body and to engage the second fulcrum surface to lever the slug further out of the interior of the blade body, and wherein the first distance is between about ½ inch and about 1 inch in order to lever out a slug having a thickness of about ½ inch or less, and wherein the second distance is between about 1½ inch and 2 inches in order to lever out a slug having a thickness of about 1½ inch or less.

2 . The hole cutter of claim 1 , wherein the first fulcrum surface is curvilinear.

3 . The hole cutter of claim 2 , wherein the second fulcrum surface is curvilinear.

4 . The hole cutter of claim 1 , wherein the at least one elongated aperture comprises a plurality of the elongated apertures formed through the blade body and angularly spaced relative to each other around a circumference of the blade body.

5 . The hole cutter of claim 1 , wherein the first fulcrum surface and the second fulcrum surface are angularly spaced around a circumference of the blade body from each other.

6 . The hole cutter of claim 5 , wherein the hole cutter defines a direction of rotation that is a cutting direction of the cutting edge, and the first fulcrum surface and the second fulcrum surface are angularly spaced around the circumference of the blade body in the direction of rotation in order of decreasing distance from the cutting edge of the fulcrum surfaces.

7 . The hole cutter of claim 1 , wherein the first portion is located at approximately a first end of the aperture and the second portion is located at approximately a second end of the aperture opposite the first end.

8 . The hole cutter of claim 1 , wherein the at least one elongated aperture is oriented generally at an acute angle relative to the longitudinal axis of the blade body.

9 . The hole cutter of claim 1 , wherein the at least one elongated aperture further comprises a third portion with a third fulcrum surface axially spaced from the cutting edge by a third distance that is between the first distance and the second distance, the third distance between about 1 inch and 1½ inch to lever out a slug having a thickness of about 1 inch or less.

10 . The hole cutter of claim 9 , wherein the at least one elongated aperture further comprises a second intermediate portion connecting the second portion and the third portion.

11 . A method of levering a slug out of an interior of a hole cutter that includes a substantially cylindrical blade body defining a cutting edge a longitudinal axis, the method comprising:
inserting a lever into an elongated aperture formed through the blade body and spaced from the cutting edge such that a portion of the blade body extends between the cutting edge and the elongated aperture, the elongated aperture including a first portion with a first fulcrum surface axially spaced from the cutting edge by a first distance, a second portion with a second fulcrum surface axially spaced from the cutting edge by a second distance greater than the first distance, and an intermediate portion connecting the first portion and the second portion and oriented at an acute angle to the longitudinal axis of the blade body; levering the lever against the second fulcrum surface to push the slug at least partially out of the interior of the hole cutter by pushing a bottom of the slug toward the first fulcrum portion; and levering the lever against the first fulcrum surface to push the slug further out of the interior of the hole cutter by pushing the bottom of the slug further toward the cutting edge.

12 . The method of claim 1 , wherein the first fulcrum surface and the second fulcrum surface are angularly spaced around a circumference of the blade body from each other.

13 . The method of claim 12 , wherein the hole cutter defines a direction of rotation that is a cutting direction of the cutting edge, and the first fulcrum surface and the second fulcrum surface are angularly spaced around the circumference of the blade body in the direction of rotation in order of decreasing distance from the cutting edge of the fulcrum surfaces.

14 . The method of claim 11 , wherein the first portion is located at approximately a first end of the aperture and the second portion is located at approximately a second end of the aperture opposite the first end.

15 . The method of claim 11 , wherein the aperture is oriented generally at an acute angle relative to the longitudinal axis of the blade body.

16 . The method of claim 11 , wherein each of the first fulcrum surface and the second fulcrum surface include a curvilinear portion engaged by the lever.

17 . The method of claim 11 further comprising, prior to levering the lever against the second fulcrum surface, levering the lever against a third fulcrum surface in a third portion of the elongated aperture to push the bottom of the slug toward the second portion, the third fulcrum surface axially spaced from the cutting edge by a third distance greater than the second distance.

18 . The method of claim 17 , wherein a second intermediate portion connects the third portion and the second portion.

19 . The method of claim 17 , wherein the third fulcrum surface is angularly spaced around a circumference of the blade body from the first fulcrum surface and the second fulcrum surface.

20 . The method of claim 17 , wherein each of the first fulcrum surface, the second fulcrum surface, and the third fulcrum surface include a curvilinear portion engaged by the lever.

Assignees

• Black & Decker Inc

Inventors

• Novak Joseph Thomas
• Green Matthew Christopher

Classifications

• Y10T408/895

  Having axial, core-receiving central portion · CPC title

• B23B2260/082

  Holes · CPC title

• B23B51/0453 Primary

  with ejecting devices · CPC title

• B23B51/0406

  Operations & Transport · mapped topic

• B23B2251/428

  Operations & Transport · mapped topic