Milwaukee Electric Tool Corporation

Brett A Parendo

David Hlavac

Alexander R Greenhill

Richard Hohnl, Jr

Ingolfur Ludviksson

Michael J Zimmermann

Douglas W Allen

James J Van Essen

Max R Sawa

James Ernest Pangerc

Carter A Gibson

Bryan C Ward

Andrew J Schulz

WeiJie Wu

Gang Huang

Marcus Carli

Jr Richard Hohnl

A method of manufacturing a drill bit includes providing a piece of bar stock having a first end, a second end opposite the first end, and an axis of rotation extending centrally through the bar stock between the first and second ends, cutting the first end of the bar stock to form a first tip angle at an oblique angle measured through the axis of rotation, cutting the first end of the bar stock at a second tip angle measured through the axis of rotation to form first tip surfaces and second tip surfaces. The first tip surfaces have the first tip angle and the second tip surfaces have the second tip angle. The second tip angle is smaller than the first tip angle. Finally forming a flute in the bar stock between the first and second ends and forming a shank at the second end of the bar stock.

Drill bit

An accessory tool includes an adapter end, and a shank coupled to the adapter end and including a first length. The shank includes a tool engagement portion, and a first reduced portion disposed between the tool engagement portion and the adapter end. The first reduced portion has a second length. The shank additionally includes a second reduced portion formed in the tool engagement portion between the first reduced portion and an end of the shank. The second length is 2.5% to 15% of a total length of the accessory tool.

Accessory tool

A step drill bit includes a shank and a body having a proximal end adjacent the shank and a distal end opposite the proximal end. The body defines a plurality of axially stacked, progressively sized steps including a first step at the distal end, a terminal step at the proximal end, and a plurality of intermediate steps having incrementally increasing diameters disposed between the first and terminal steps. The step drill bit also includes a plurality of cutting edges each disposed along one of the plurality of steps. Each edge defines a helix angle and a radial rake angle. The radial rake angle and the helix angle of the cutting edge at the terminal step is greater than the radial rake angle and the helix angle of the cutting edge at the first step.

Step drill bit

A drill bit includes a body having a first end, a second end opposite the first end, and an axis of rotation extending centrally through the body. The drill bit includes a cutting head with a cutting tip on the axis of rotation and a cutting portion. The cutting portion includes first tip surfaces on opposite sides of the axis of rotation and second tip surfaces on opposite sides of the axis of rotation. Each first tip surface extends radially outward from the cutting tip to a corresponding second tip surface. Each second tip surface extends from a corresponding first tip surface to an outer periphery of the body. The first tip surfaces define a first tip angle measured through the axis of rotation that is oblique. The second tip surfaces define a second tip angle measured through the axis of rotation that is smaller than the first tip angle.

A drill bit includes a body having a first end, a second end, and an axis of rotation extending centrally through the body from the first end to the second end. The drill bit also includes a shank adjacent the second end. The drill bit further includes a cutting head adjacent the first end. The cutting head includes a pilot tip and a cutting portion. The cutting portion has first tip surfaces and second tip surfaces on opposite sides of the pilot tip. Each first tip surface extends radially outward from the pilot tip to a corresponding second tip surface. The first tip surfaces define a first tip angle through the axis of rotation that is less than 180 degrees. The second tip surfaces define a second tip angle through the axis of rotation that is smaller than the first tip angle.

A drill bit includes a shank extending along a bit axis and a body with a proximal end adjacent the shank and a distal end opposite the proximal end. The body defines a plurality of axially stacked, progressively sized steps including a first step at the distal end and a terminal step at the proximal end. The drill bit also includes a flute in the body. The flute defines an elongated groove that extends from the distal end to the proximal end. The drill bit further includes a plurality of cutting edges formed in the body. Each cutting edge is disposed along one of the plurality of steps and defines a helix angle and a rake angle. The helix angle of the cutting edge at the terminal step is greater than the helix angle of the cutting edge at the first step. A ratio of the helix angle to the rake angle of the cutting edge at the first step is in a range from 0.5 to 2.4, and a ratio of the helix angle to the rake angle of the cutting edge at the terminal step is in a range of 0.9 to 1.7.

A tool, such as a hole saw, including an open end cap geometry is provided. The end cap includes spokes extending between a hub and a rim. A plurality of openings are defined between the spokes, hub and rim. The area of the openings is substantially large relative to the area of the end cap such that the end cap is relatively lightweight and provides access into the hole saw for debris removal. The spokes are shaped and positioned to provide strength to the end cap.

Hole saw with open end cap geometry

An accessory tool includes an adapter end having a maximum outer dimension, and a shank coupled to the adapter end. The shank includes a tool engagement portion including a cross section having a maximum outer width, a first reduced portion disposed between the tool engagement portion and the adapter end and having a first minimum outer dimension and a first length, and a second reduced portion formed in the tool engagement portion between the first reduced portion and an end of the shank. The second reduced portion is engaged by the tool to secure the shank to the tool, and has a second minimum outer dimension and a second length. The maximum outer dimension is greater than the maximum outer width. The maximum outer width is greater than the first minimum outer dimension and greater the second minimum outer dimension. The first length is greater than the second length.

An accessory tool includes an effector end and a shank coupled to the effector end. The shank includes a tool engagement portion that is configured to be received within a tool and a reduced diameter portion disposed between the tool engagement portion and the effector end. The shank defines a first length, and the reduced diameter portion defines a second length that is 10% to 45% of the first length.

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Milwaukee, WI, United States of America

Brett A Parendo