Abstract: 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.

Abstract: 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 a first plastic, such as by insert molding. 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. Where the commutator is a tang type commutator, the commutator ring has notches at axial ends of the slots which is filled with the second plastic when the second plastic is molded. The mold used to mold the first plastic includes projections that extend between the tangs of the commutator and against the notches at axial ends of the slots of the commuter.

Abstract: An electric motor, power tool using the electric motor, and method of making the electric motor includes making a stator to have pole pieces on which field coils are disposed. Each field coil has a plurality of coils where each coil serves a different function in that field coil. In an aspect, one of the coils is a run coil and wound with larger wire and another of the coils is a brake coil wound with smaller wire.

Abstract: A tool and method for winding and forming a field coil for field assembly, such as a stator, includes separable tool halves defining a winding cavity therebetween. The winding cavity receives magnet wire that is wound therein, such as by rotating the tool or a winding nozzle. The magnet wire generally conforms to the shape of the winding cavity such that when the tool halves are separated, a field coil having a net shape is produced. Once the magnet wire is sufficiently deposited within the winding cavity, wires of the coil may be bonded together either through a resistive heating process such as by passing an electrical current through the coil or through other heating or chemical bonding methods to thereby maintain the net shape of the field coil once it is removed from the tool.

Abstract: A cylinder/magnet assembly for a field of an electric machine, such as a stator of a brush type motor or a rotor of a brushless motor, alternator or generator, is formed by stamping a blank to form anchors extending upwardly from a surface of the blank and stamping holes in the blank where first and second portions of the anchors meet an inner surface of the cylinder to facilitate rolling of the cylinder from the blank. After a cylinder is rolled from the blank, pre-formed magnets are placed around an inner surface of the cylinder and plastic molded around the magnets and anchors to secure the magnets to the cylinder. In an aspect of the invention, the holes act as magnetic chokes. In another aspect of the invention, the anchors are formed as flux spreaders. In another aspect of the invention, the north and south poles of a cylinder and magnet assembly have unequal distribution angles.

Abstract: A stator of an electric motor is formed by inserting pre-formed magnets on a cylinder having anchors and plastic is molded around the magnets and anchors to secure the magnets to a surface of the cylinder, forming a cylinder/magnet assembly. A pilot feature is formed in at least one endwall of the plastic molding when it is molded. An end plate is located with respect to the cylinder/magnet assembly by mating a corresponding pilot feature of the end plate with the pilot feature in the endwall of the plastic molding. In another aspect of the invention, magnets are inserted into magnet receiving pockets of a cylinder and plastic molded therearound with the magnet pockets holding the magnets in place during molding of the plastic. In another aspect of the invention, the north and south poles of a cylinder and magnet assembly have unequal distribution angles. In another aspect of the invention, the north and south poles of a cylinder and magnet assembly have unequal numbers of magnets.

Abstract: A cylindrical magnet ring assembly having a cylinder magnet flux ring (102) formed with a plurality of inwardly projecting anchors (108); a plurality of permanent magnets (104), wherein the magnet can be formed with step portions (112) in the inner radial surface; a molded plastic member (106) being molded around the magnets and anchors to secure the magnets to a surface of the cylinder flux ring. There are several variations of the embodiments of the invention. Few embodiments are the following: in one aspect of the invention, magnets are inserted into magnet molded around an assembly ring (806) and the molded plastic secures the assembly ring to the flux ring; in another aspect, there are two assembly rings, a first assembly ring (is inserted into the one side of the cylinder flux ring then the second assembly ring is inserted into the other side of the cylinder flux ring and mated to the first assembly ring, after that the molded plastic secures the two assembly rings.

Abstract: A power tool motor pack that includes common components adapted to couple to a first component customized for a first power tool application and to couple to a second component customized for a second power tool application. When the motor pack is used in the first power tool application, the common components are coupled to the first customized component. When the motor pack is used in the second power tool application, the common components are coupled to the second customized component.

Abstract: A brush assembly has a base with a member to secure the base to a motor end cap assembly. A brush housing is associated with the base. The brush housing includes first and second open ends. A brush, defining an axis, is slidably supported within the housing. The brush extends from one of the first and second open ends. The brush includes a surface with a spring retention plunge. The spring retention plunge defines an arcuate face angled relative to the axis. A biasing member exerts a force directly on the arcuate face to bias the brush into contract with a commutator. An electrical connection is made between the commutator and a power supply.

Abstract: A stator of an electric motor is formed by inserting pre-formed magnets on a cylinder having anchors and plastic is molded around the magnets and anchors to secure the magnets to a surface of the cylinder, forming a cylinder/magnet assembly. A pilot feature is formed in at least one endwall of the plastic molding when it is molded. An end plate is located with respect to the cylinder/magnet assembly by mating a corresponding pilot feature of the end plate with the pilot feature in the endwall of the plastic molding. In another aspect of the invention, magnets are inserted into magnet receiving pockets of a cylinder and plastic molded therearound with the magnet pockets holding the magnets in place during molding of the plastic. In another aspect of the invention, the north and south poles of a cylinder and magnet assembly have unequal distribution angles. In another aspect of the invention, the north and south poles of a cylinder and magnet assembly have unequal numbers of magnets.

Abstract: An electric motor, power tool using the electric motor, and method of making the electric motor includes making a stator that includes pole portions that have dovetail features that are received in corresponding recesses of the back iron portion.

Abstract: A stator assembly for an electric motor includes a stator housing, an expandable flux ring inserted into the stator housing and a plurality of magnets on an inner surface of the flux ring. Overmold material is molded around the magnets in the flux ring, such as by injection molding. The pressure of the overmold material as it is being molded expands the flux ring pressing the flux ring into engagement with the stator housing. The overmold material secures the magnets to the flux ring and the flux ring to the housing. One of the flux ring and stator housing has a dimple that engages a hole in the other of the flux ring and stator housing to align the flux ring and stator housing. In an aspect, the overmold material is molded to form at least one of a commutator end or rear bearing support, front bearing support and fan baffle. In an aspect, the overmold material is molded to form a keying feature. The keying feature can be slots of different widths between magnetic poles of the stator assembly.

Abstract: An electric motor, power tool using the electric motor, and method of making the electric motor includes making a stator that includes pole portions that have axially opposed ends that gradually decrease in width. The pole portions may also have dovetail features that are received in corresponding recesses of the back iron portion.

Abstract: An electric motor, power tool using the electric motor, and method of making the electric motor includes making a stator that includes pole portions that have axial lengths less than an axial length of a back iron portion. Alternatively, or in addition, the pole portions have axially opposed ends that decrease in width. Alternatively, or in addition, the pole portions have dovetail features that are received in corresponding recesses of the back iron portion.

Abstract: An electrically conductive brush box is located against the upper surface of a base and has crimping tabs located against an oppositely disposed crimping surface. The base is formed of high temperature resistant plastic. A field case housing has a seat with a retention member adapted to retain the base against the seat. A screw is threaded into the field case housing such that the head presses against a surface of the base member to retain the base member in the seat. The screw member is located in non-contacting relationship with the electrically conductive brush box. A spacer member is adapted to space the portion of the crimping tab against the crimping surface away from the field case housing. The brush box includes a biasing member holder and the crimping tabs are located adjacent the holder.

Abstract: A stator assembly for an electric motor includes a stator housing, a flux ring inserted into the stator housing after the stator housing is formed and a plurality of magnets on an inner surface of the flux ring. Overmold material is molded around the magnets in the flux ring, such as by injection molding. The overmold material secures the magnets to the flux ring and the flux ring to the housing. In an aspect, the overmold material is molded to form at least one of a commutator end or rear bearing support, front bearing support and fan baffle.

Abstract: A field case housing has a substantially cylindrical wall segment, an end segment and a flange all having a substantially constant wall thickness. The flange has reinforcing ribs connected to the wall segment and aperture reinforcing bosses. The end segment, the wall segment and the flange are formed as a single, integral part adapted to reduce warping of the housing during molding. A cylindrical guide member is located in the field case housing and a conical guide member is located in the fan baffle. The cylindrical guide member is adapted to insure a screw passing through the cylindrical guide member is guided to a point within the conical guide member. The fan baffle has a transverse wall with an aperture and guide walls extending adjacent the aperture. The guide walls are adapted to guide an armature past the magnets without contacting and damaging them.

Abstract: A cylinder/magnet assembly for a field of an electric machine, such as a stator of a brush type motor or a rotor of a brushless motor, alternator or generator, is formed by stamping a blank to form anchors extending upwardly from a surface of the blank and stamping holes in the blank where first and second portions of the anchors meet an inner surface of the cylinder to facilitate rolling of the cylinder from the blank. After a cylinder is rolled from the blank, pre-formed magnets are placed around an inner surface of the cylinder and plastic molded around the magnets and anchors to secure the magnets to the cylinder. In an aspect of the invention, the holes act as magnetic chokes. In another aspect of the invention, the anchors are formed as flux spreaders. In another aspect of the invention, the north and south poles of a cylinder and magnet assembly have unequal distribution angles.

Abstract: 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.

Abstract: An electric motor has a field assembly, such as a stator, 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. 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. The pole pieces and return path pieces are formed with mating features that are mated to hold the pole pieces and return path pieces together.