Patent application number | Description | Published |
20090126184 | Method of making an armature - An armature for an electric motor has a lamination stack on a shaft with a commutator mounted on one end of the shaft. Magnet wires wound in slots in the lamination stack, the commutator and armature shaft are at least partially encapsulated in thermoset. 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, such as phenolic, in the commutator ring before the commutator ring is mounted on the armature shaft. Prior to molding the thermoset, the commutator ring is sealed. The seal prevents the thermoset from flowing into the slots between the commutator ring segments or over the commutator ring. | 05-21-2009 |
20090200891 | Electric Motor Having A Field Assembly With Slot Insulation - 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. | 08-13-2009 |
20100013336 | Anchoring System For A Stator Housing Assembly Having An Overmolding; Power Tool With Same - A permanent magnet electric motor has a stator and a rotor The stator has a stator housing with opposed axial ends and features skived in the stator housing to extend radially inwardly from an inner surface of the stator housing proximate to at least one of the axial ends of the stator housing. An overmolding of material is molded around the features. In an aspect, the overmolding of material is a magnetic composite material and is molded to form magnets. In an aspect, magnets are placed on the inner surface of the stator housing and the overmolding of material is a plastic that is over molded around the magnets and the features. In an aspect, the features hold the magnets in place during the molding of the overmolding around the magnets. In an aspect, the magnets have essentially the same inner radius and outer radius and the overmolding of material is thicker at edges of each magnet than at the center of each magnet. In an aspect, the magnets are flat magnets and the overmolding of material is thicker at edges of each magnet than at the center of each magnet. In an aspect a power tool has such a permanent magnet DC motor. In an aspect, a power tool has a housing with a permanent magnet electric motor in the housing, with an member coupled to the electric motor. The electric motor has a rotor and a stator but not an end plate. The stator has a stator housing having opposed axial ends and a plurality of magnets affixed to an inner surface of the stator housing and an overmolding of material molded around the magnets. The overmolding of material includes a pilot feature that mates with a pilot feature of a bearing support of the power tool. | 01-21-2010 |
20110126399 | METHOD OF MAKING AN ARMATURE - An armature for an electric motor has a lamination stack on a shaft with a commutator mounted on one end of the shaft. Magnet wires wound in slots in the lamination stack, the commutator and armature shaft are at least partially encapsulated in thermoset. 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, such as phenolic, in the commutator ring before the commutator ring is mounted on the armature shaft. Prior to molding the thermoset, the commutator ring is sealed. The seal prevents the thermoset from flowing into the slots between the commutator ring segments or over the commutator ring. | 06-02-2011 |
20130055554 | METHOD OF FORMING A POWER TOOL - 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. | 03-07-2013 |
20130057090 | 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. | 03-07-2013 |
20130162068 | OVERMOLDED STATOR ASSEMBLY LAMINATION STACK FOR A POWER TOOL - A power tool is provided, including a housing, a permanent magnet electric motor in the housing, and an output member coupled to the electric motor. The electric motor includes a rotor and a stator with at least a North pole and a South pole. The stator includes a lamination stack having loose laminations held together via an overmolded resin. The overmolded resin include a longitudinal overmold layer covering at least a portion of at least one of an inner or outer surfaces of the lamination stack, and two end cap portions extending laterally from the ends of the longitudinal overmold layer to firmly cover ends of the lamination stack. | 06-27-2013 |
20130270934 | STATOR ASSEMBLY FOR A BRUSHLESS MOTOR IN A POWER TOOL - A power tool includes a motor having a stator assembly and a rotor pivotably arranged inside the stator. The stator assembly includes a lamination stack defining a plurality of poles; a plurality of field windings each arranged at at least two opposite poles of said plurality of poles and connected together around the stator assembly; and a plurality of conductive terminals longitudinally arranged along an outer surface of the lamination stack and electrically coupled to the plurality of field windings and a power source. | 10-17-2013 |
20130291371 | METHOD OF FORMING A POWER TOOL - 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. | 11-07-2013 |
20130300221 | METHOD OF FORMING A POWER TOOL - 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. | 11-14-2013 |
20130342041 | STATOR ASSEMBLY FOR A BRUSHLESS MOTOR IN A POWER TOOL - A power tool is provided including a housing and a motor housed inside the housing. The motor includes a stator assembly and a rotor pivotably arranged inside the stator assembly. The stator assembly includes a lamination stack defining poles extending radially towards a center of the lamination stack, pole teeth extending laterally with respect to ends of the poles, and stator slots formed between adjacent poles. The stator assembly also includes field windings wound around the poles. Electrically non-conductive tooth damper inserts are longitudinally arranged inside the stator slots between adjacent field windings, each tooth damper insert including a radial outer end in contact with an outer wall of the slot and a radial inner end arranged at an open end of the slot and engaging lateral edges of two opposing teeth within the slot. | 12-26-2013 |
20140076953 | Motor and Electronics Cooling System for a High Power Cordless Nailer - A battery powered tool includes a housing containing a motor assembly. A fan positioned in the housing is rotated by the motor assembly. The fan has a circular ring/body and further has multiple fan blades directly connected to the circular ring body. The circular ring/body defines a concave shaped surface having the fan blades directly connected to the concave shaped surface. A housing cover includes: first and second extending walls; a slot created between the first and second extending walls; and multiple air intake vents all positioned in a lower housing zone separated from an upper housing zone by the slot. An electronics module is positioned in the housing proximate to the housing cover lower housing zone such that air entering the intake vents passes only through the lower housing zone and past the electronics module to cool the electronics module before entering the fan. | 03-20-2014 |
20140100687 | Power tool hall effect mode selector switch - A mode selector switch for a power tool that can have a source of a magnetic field and use a magnetoresistive component to produce an output signal that changes when the strength of the magnetic field changes. The power tool can have a microprocessor that changes an operational mode of the power tool based on a change of the output signal from the magnetoresistive component. The magnetoresistive component can be a Hall effect sensor and the power tool can be a nailer. The power tool can have a switching means which changes an operational mode based upon a change in the strength of the magnetic field upon a magnetoresistive component. A method of controlling a power tool, having a step of changing an operational mode of a power tool based upon identifying a change in output from a magnetoresistor. | 04-10-2014 |
20140360008 | METHOD OF FORMING A POWER TOOL - 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. | 12-11-2014 |
20150042183 | MOTOR HAVING A TWO-PIECE STATOR END RING - A power tool is provided including a housing and an electric motor disposed in the housing. The motor includes a stator having a lamination stack having separately-formed pole pieces and field coils disposed on the pole pieces, and an armature disposed in the stator. An end ring is disposed at an end of the lamination stack, the end ring including at least two ring pieces mated together around a portion of the field coils extending beyond pole tips of the pole pieces. | 02-12-2015 |