Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A method of manufacturing a power tool includes forming an armature by placing an electrically insulative sleeve on an armature shaft, securing a lamination stack having slots therein on the armature shaft with the insulative sleeve disposed therebetween, securing a commutator on one end of the armature shaft with the insulative sleeve disposed therebetween, winding magnet wires in the slots in the lamination stack and securing ends of the magnet wires to the commutator, and molding thermally conductive plastic to at least partially encase the magnet wires in plastic. The armature is then disposed in a stator to form an electric motor and the electric motor is disposed in a power tool. In an aspect, electrically insulative plastic is molded in the slots of the lamination stack to form slot liners and around the ends of the lamination stack to form end spiders.

Abstract: A method of making an armature includes placing a commutator and a lamination stack on an armature stack. Coil windings wound in slots in the lamination stack, the commutator and armature shaft are at least partially encapsulated in a first plastic. The commutator has a commutator ring divided into a plurality of segments with slots between the segments that are filled with a second plastic when the commutator is made by molding a core of the second plastic in the commutator ring before the commutator ring is mounted on the armature shaft. The mold used to mold the first plastic includes projections that extend between the tangs of the commutator and against notches at axial ends of the slots of the commutator. The notches filled with the second plastic and the projections of the mold prevent plastic flash from getting into the slots of the commutator ring.

Abstract: A method for forming an armature for an electric motor includes securing a lamination stack having slots therein on an armature shaft. A commutator is secured on one end of the armature shaft. Magnet wires are wound in the slots in the lamination stack and ends of the magnet wires are secured to the commutator. Plastic is molded around the lamination stack, commutator and magnet wires. Excess plastic is machined off. The magnet wires can have a layer of heat activated adhesive that is activated when the plastic is molded. Slots in the lamination stack can include slot liners formed of thermally conductive plastic. A fan can be formed when the thermally conductive plastic is molded to encapsulate the magnet wires.

Abstract: An electric motor has an armature and a stators. The armature has a lamination stack having slots therein. An internal shaft extends coaxially through the lamination stack. A plurality of magnet wires are wound in the slots of the lamination stack. A commutator is disposed on the armature shaft to which ends of the magnet wires are electrically coupled. The internal is shaft coupled to an external pinion and bearing journal by an insulated coupling. The magnet wires are at least partially encased in thermally conductive plastic. The magnet wires can have a layer of heat activated adhesive that is activated when the plastic is molded. Slots in the lamination stack can include slot liners formed of thermally conductive plastic. A fan can be formed when the thermally conductive plastic is molded to encapsulate the magnet wires. A power tool has the electric motor.

Abstract: Magnet wires wound in slots in a lamination stack of a dynamoelectric machine are encapsulated, in whole or in part, with plastic. The plastic may be thermally conductive and have features molded therein that enhance heat transfer. The plastic may stiffen the armature and increase its critical speed. Characteristics of the plastic, its geometry and its distribution may be varied to adjust spinning inertia and resonant frequency of the armature. The magnet wires may be compressed into the slots, by application of iso-static pressure or by the pressure of the plastic being molded around them. Larger magnet wire can then be used which increases the power of the electric motor using the armature having the larger magnet wire. A two or three plate mold may be used to mold the plastic around the armature. Balancing features can be molded in place. The plastic can have a base polymer that is a blend of two or more polymers and various thermally conductive fillings.

Abstract: Magnet wires wound in slots in a lamination stack of a dynamoelectric machine are encapsulated, in whole or in part, with thermally conductive plastic. Pre-formed features having a thermal conductivity higher than the thermally conductive plastic are insert molded when the plastic is molded. The pre-formed features may include a finned end cap and a fan. Alternatively, end domes of the plastic over end coils of the wound magnet wires have a metallic layer on them, such as by being metallized. The end domes can be formed with features which are also metallized. The thermally conductive plastic can have a phase change additive in it. The magnet wires can have a layer of heat activated adhesive that is activated when the plastic is molded. Slots in the lamination stack can include slot liners formed of thermally conductive plastic. A fan can be formed when the thermally conductive plastic is molded to encapsulate the magnet wires.

Abstract: Magnet wires wound in slots in a lamination stack of a dynamoelectric machine are encapsulated, in whole or in part, with plastic. The plastic may be thermally conductive and have features molded therein that enhance heat transfer. The plastic may stiffen the armature and increase its critical speed. Characteristics of the plastic, its geometry and its distribution may be varied to adjust spinning inertia and resonant frequency of the armature. The magnet wires may be compressed into the slots, by application of iso-static pressure or by the pressure of the plastic being molded around them. Larger magnet wire can then be used which increases the power of the electric motor using the armature having the larger magnet wire. A two or three plate mold may be used to mold the plastic around the armature. Balancing features can be molded in place. The plastic can have a base polymer that is a blend of two or more polymers and various thermally conductive fillings.

Abstract: Magnet wires wound in slots in a lamination stack of a dynamoelectric machine are encapsulated, in whole or in part, with thermally conductive plastic. Pre-formed features having a thermal conductivity higher than the thermally conductive plastic are insert molded when the plastic is molded. The pre-formed features may include a finned end cap and a fan. Alternatively, end domes of the plastic over end coils of the wound magnet wires have a metallic layer on them, such as by being metallized. The end domes can be formed with features which are also metallized. The thermally conductive plastic can have a phase change additive in it. The magnet wires can have a layer of heat activated adhesive that is activated when the plastic is molded. Slots in the lamination stack can include slot liners formed of thermally conductive plastic. A fan can be formed when the thermally conductive plastic is molded to encapsulate the magnet wires.