Black Decker Inc.

Hung T Du

Earl M Ortt

Brandon L Verbrugge

Richard Thomas Walter

David J Smith

Michael Jeffrey Agnes

Joshua F West

Michael R Sell

John C Stone

Ren H Wang

Howard T White

Robert G Kusmierski

Garrett Patrick McCormick

Michael A Zemlock

Jiaqi Zhang

Frank A Mannarino

Michael A Zemlok

Kevin M Hogan

Allyn Boyce

Shane Ashley Moll

Bhanuprasad V Gorti

Spencer G Maid

James C Benton

Richard H Walter

Mark W Wood

Todd A Hagan

Alan Gene Phillips

Shailesh P Waikar

Sankarshan N Murthy

Robert J Marcinkowski

Michael Anthony Lagaly

Michael P Kunz

Uday S Deshpande

C Kerwin Braddock

Julie Lynn Jones

Barbara Rose

James Andrew Patton

Joshua D West

Daniel U Goodwin

Patrick Gerald Barry

Eric J Samuelsen

Peter Zhao

J Michael Weaver

Deborah Lynn Harr

Garrett P Mccormick

Allison A Smith

Eric L Bernstein

Josh West

Morris R Davies

Therese M Rakosky

Kyle J Wheaton

Antonios M Nicolaidis

Ren Hong Wang

A method of manufacturing an armature for an electric motor, includes: placing a commutator and a lamination stack on an armature shaft, winding magnet wire in slots in the lamination stacks to form coils, attaching ends of the magnet wire to the commutator, and molding plastic around the magnet wire and around the shaft of the armature at ends of the lamination stack. A spinning inertia of the armature is adjusted by adjusting at least one of a mass of the plastic molded and a distribution of the plastic molded. Alternatively and/or additionally, at least one of a resonant frequency and critical speed of the armature is adjusted by adjusting at least one of a geometry of the plastic molded, the physical properties of the plastic and the mechanical properties of the plastic.

Method of manufacturing a power tool with molded armature

A method for forming an armature for an electric motor includes: securing a lamination stack having slots therein on an armature shaft, securing a commutator on one end of the armature shaft, winding magnet wires in the slots in the lamination stack and securing ends of the magnet wires to the commutator, the magnet wires having armature lead wires that extend from the slots to the commutator; and molding plastic over the magnet wires to encase at least the armature lead wires in plastic. Alternatively and/or additionally, plastic is molded over the magnet wires to retain them in the slots and to support the armature lead wires and prevent them from vibrating when the armature rotates during operation.

Method of forming a power tool

An electric motor for a power tool includes a stator and an armature disposed in the stator. The armature includes a lamination stack having slots therein; an armature shaft extending coaxially through the lamination stack; a plurality of magnet wires wound in the slots of the lamination stack; a commutator disposed on the armature shaft to which ends of the magnet wires are electrically coupled; and thermally conductive plastic at least partially encasing the magnet wires, the thermally conductive plastic having a base polymer that is a blend of at least two polymers.

An electric motor has a stator in which an armature is disposed. The armature has a shaft. One of the stator or the armature includes a lamination stack having slots in which magnet wires are wound, the magnet wires having a coating of heat activated adhesive. There is further provided plastic molded around the magnet wires with heat of the plastic activating the heat activated adhesive on the magnet wires during molding of the plastic to bond the magnet wires together.

An electric motor has a rotor and a stator. The rotor or the stator has arced permanent magnets that have essentially the same inner radius (IR) and outer radius (OR). In an aspect, the stator has a stator housing having a plurality of poles. Each pole includes a plurality of flat magnets affixed to an inner surface of the stator housing. In an aspect, flats on the outside of the stator housing key the stator assembly in a power tool housing. In an aspect, flat magnets are pre-magnetized, pre-assembled with alternating magnetic polarities, inserted into a stator housing, and remagnetized to a final, desired magnetic polarity configuration. In an aspect, pre-magnetized magnets and unmagnetized magnets are pre-assembled with unmagnetized magnets between magnetized magnets, the pre-assembled magnets inserted into a stator housing, and the unmagnetized magnets magnetized to a final, desired magnetic polarity configuration. In an aspect, pre-magnetized magnets are inserted between anchors inwardly extending from an inner surface of a stator housing with the anchors retaining each magnet placed in the stator housing between anchors from being angularly displaced by subsequently inserted magnets. In an aspect, pre-magnetized magnets are inserted in recesses in an inner surface of a stator housing with the recesses retaining each magnet placed in the stator housing between anchors from being angularly displaced by subsequently inserted magnets. In an aspect, each pole has at least three magnets, at least one of the magnets being thinner than the other magnets. In an aspect, the outer most magnets are made of magnetic material that is more resistant to demagnetization than at least one of the other magnets. In an aspect, the magnets of each pole are unevenly spaced over the pole In an aspect, a power tool includes such an electric motor.

Motor with permanent magnets having essentially the same inner and outer radius; and method of manufacturing a motor stator housing with permanent magnets

A cordless power tool () has a transmission () having multiple speed ranges In the light torque range, the speed of a motor () of the cordless power tool is held constant to hold an output speed of the transmission () constant until motor power reaches a predetermined percentage of the maximum watts out of the motor.

Cordless power tool having multi-speed transmission and constant speed in light torque range

A power tool has a motor having a stator made by separately forming pole pieces and field coils. The field coils are placed over necks of the pole path pieces. An armature has an outside diameter of at least 0.625 the outside diameter of the stator is placed in the stator. The housing has a girth of 200 mm or less with the motor wound to provide a maximum watts out to housing girth ratio of at least 5 maximum watts outs to 1 mm of housing girth. The field coils may be formed so that they extend beyond pole tips of the pole pieces.

Power tool with motor having a multi-piece stator

An electric motor has a stator in which an armature is disposed. The armature has a lamination stack having slots in which magnet wires are wound. An armature shaft extends coaxially through the lamination stack and a commutator is disposed on the armature shaft to which ends of the magnet wires are electrically coupled. The magnet wires are at least partially encased in thermally conductive plastic. When the thermally conductive plastic is molded, a balancing feature is formed of the thermally conductive plastic. In aspects, the balancing feature can include a layer of the plastic from which plastic can be removed during balancing; one or more balancing rings adjacent axial sides of the lamination stack from which plastic can be removed to balance the armature; or one or more balancing rings having one or more pockets therein in which one or more weights are disposed to balance the armature.

Method for forming a power tool

A power tool has a motor having a stator made by separately forming pole pieces, return path pieces and field coils. The field coils are placed over necks of the pole path pieces and the return path pieces are affixed to the pole pieces. An armature having an outside diameter of at least 0.625 the outside diameter of the stator is placed in the stator. The field coils may be formed so that they extend beyond pole tips of the pole pieces.

Power tools with motor having a multi-piece stator

A power tool has an electric motor with field windings. Each field winding includes two coils. When the motor is first energized, the two coils of each field winding are connected in series, reducing in-rush current. Upon expiration of a soft start period, the two coils of each field winding are connected in parallel. In another aspect, the field windings that are connected in series with a separate start winding when the motor is first energized. Upon expiration of the soft start period, the start winding is bypassed. In another aspect, the field windings are connected in series with a start impedance when the motor is first energized and a time delay relay having a set of delay contacts coupled across the start impedance energized. Upon expiration of the soft start period, the time delay contacts close, bypassing the start impedance. In an aspect, the motor is a universal motor.

Soft start for electric motor of a power tool

A method of forming a power tool includes forming and balancing an armature by securing a lamination stack having slots therein on an armature shaft securing a commutator on one end of the armature shaft, winding magnet wires in the slots in the lamination stack and securing ends of the magnet wires to the commutator, and molding plastic to at least partially encase the magnet wires in plastic and forming a balancing feature. Plastic is removed from the balancing feature during dynamic balancing of the armature. The armature is then disposed in a stator to form an electric motor and the electric motor is disposed in a power tool.

An electric motor has a field assembly, such as a stator, for a dynamoelectric machine has field coils that are wound to a net shape. Lead wires are brought out from the ends of each field coil. The field coils are insulated with insulating sleeves or insulating slot liners. The field coils are assembled with stator core pieces, such as pole pieces and return path pieces, into the stator. The stator core pieces are formed prior to being assembled with the field coils. In an aspect of the invention, the pole pieces and return path pieces are separately formed and then assembled together with the field coils, which have also been separately formed.

Electric motor having a field assembly with slot insulation

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Reisterstown, MD, United States of America

Hung T Du