Abstract: An electric motor assembly includes a circuit board, a rotor assembly, and a stator assembly having a first end coupled to the circuit board and a second end opposite the first end. The stator assembly also includes an annular stator body having a plurality of inwardly projecting teeth. The stator assembly further includes windings wrapped about the stator body to form a plurality of coils. The stator assembly also includes a terminal coupled to an outer periphery of the stator body and extending longitudinally between the first end and the second end. The terminal is coupled to the circuit board at the first end and is coupled to the windings at the second end to electrically connect the windings to the circuit board. The terminal is molded to an attachment member, and the attachment member is molded to the outer periphery of the stator body.

Abstract: A method of manufacturing a brushless electric motor including providing a stator that includes a core defining a plurality of stator teeth, positioning a rotor within the stator, coupling a stator end cap to an end of the core, winding a plurality of coils on the plurality of stator teeth, and overmolding a plurality of coil contact plates within the stator end cap. The coil contact plates short-circuit diagonally opposite coils on the stator.

Abstract: An electric motor assembly includes a circuit board, a rotor assembly, and a stator assembly having a first end coupled to the circuit board and a second end opposite the first end. The stator assembly also includes an annular stator body having a plurality of inwardly projecting teeth. The stator assembly further includes windings wrapped about the stator body to form a plurality of coils. The stator assembly also includes a terminal coupled to an outer periphery of the stator body and extending longitudinally between the first end and the second end. The terminal is coupled to the circuit board at the first end and is coupled to the windings at the second end to electrically connect the windings to the circuit board. The terminal is molded to an attachment member, and the attachment member is molded to the outer periphery of the stator body.

Abstract: A power tool with a combined printed circuit board (PCB) having a doughnut shape and located coaxially with a motor shaft. The combined PCB is secured to a heat sink on one end of the motor and a metal end piece is positioned on an opposite end of the motor. The metal end cap and heat sink are secured to one another via fasteners to provide a rigid coupling. A tabbed end piece is provided between the heat sink and the motor stator and is also secured into place via the fasteners. The tabbed end piece includes wire support tabs that provide strain relief to motor coil leads. The wire support tabs extend axially from circumferential locations of the tabbed end piece and include channels to guide the motor coil leads to solder contact points on the combined PCB.

Abstract: A brushless DC motor for use with a power tool includes a stator surrounding a rotor, an output shaft with first and second ends that is fixed to the rotor to transmit movement of the rotor to the output shaft, first and second bearings positioned on the output shaft adjacent the first and second ends, a fan coupled to the output shaft between the first and second bearings to rotate with the output shaft relative to the stator, and a brass bushing with an outer diameter coupled to the output shaft and positioned between the first and second bearings closer to the first bearing than to the second bearing. A hub portion of the fan is coupled to the output shaft and fins extend radially outward away from the hub portion. An outer diameter of the brass bushing is less than the outer diameter of the hub portion.

Abstract: An electric motor includes a rotor and a stator. The stator includes a first stator segment including a first annular back portion, a first tooth extending radially inward from the first annular back portion, a first flange extending away from the first tooth, a first insulation portion at least partially covering the first annular back portion, the first tooth, and the first flange, and a first coil wound around the first tooth. The stator also includes a second stator segment separate from the first stator segment and axially coupled to the first stator segment, the second stator segment including a second annular back portion, a second tooth extending radially inward from the second annular back portion, a second flange extending away from the second tooth and toward the first flange, a second insulation portion at least partially covering the second annular back portion, the second tooth, and the second flange.

Abstract: A power tool includes a housing, a battery connection portion supported by the housing, a drive mechanism configured to operate a working element, and a brushless DC motor positioned within the housing and connected to the drive mechanism. The motor includes a rotor, stator surrounding the motor, and an output shaft fixed to the rotor such that movement of the rotor is transmitted to the output shaft. The motor also includes a fan coupled to the output shaft to rotate with the output shaft and the rotor, and a brass bushing fixed to the output shaft to rotate with the rotor and the output shaft relative to the stator. The bushing includes a balancing feature.

Abstract: A stator includes insulation including a back insulation portion covering a back stator portion, a first tooth portion covering a first tooth, a second tooth portion covering a second tooth. A first flange portion has a first face that is in facing relationship with the back insulation portion. A second flange portion has a second face that is in facing relationship with the back insulation portion. The first face and the second face together substantially defining a boundary plane, such that a cross-sectional slot area is defined between the back insulation portion, the first tooth portion, the second tooth portion, and the boundary plane. A plurality of conductive wires are arranged in the cross-sectional slot area, the wires defining a cross-sectional winding area within the cross-sectional slot area. A ratio of the cross-sectional winding area to the cross-sectional slot area is greater than or equal to 0.45.

Abstract: A power tool with a combined printed circuit board (PCB) having a doughnut shape and located coaxially with a motor shaft. The combined PCB is secured to a heat sink on one end of the motor and a metal end piece is positioned on an opposite end of the motor. The metal end cap and heat sink are secured to one another via fasteners to provide a rigid coupling. A tabbed end piece is provided between the heat sink and the motor stator and is also secured into place via the fasteners. The tabbed end piece includes wire support tabs that provide strain relief to motor coil leads. The wire support tabs extend axially from circumferential locations of the tabbed end piece and include channels to guide the motor coil leads to solder contact points on the combined PCB.

Abstract: A method of arranging windings in a parallel delta configuration in a stator assembly includes connecting a first lead of a first winding to a first terminal. The first terminal is electrically connected to a printed circuit board assembly (PCBA) located at a first axial end of the stator assembly. The method also includes wrapping the first winding about a first tooth of a lamination stack to form a first coil, extending the first winding about at least a portion of a circumference of the lamination stack at a second axial end of the stator assembly toward a second tooth located opposite the first tooth, connecting the first winding to a second terminal electrically connected to the PCBA, wrapping the first winding about the second tooth of the lamination stack to form a second coil, and connecting a second lead of the first winding to the first terminal.

Abstract: A power tool with a combined printed circuit board (PCB) that reduces internal wiring of the power tool and provides a large amount of air flow to internal components. In some instances, the combined PCB has a surfboard shape and includes a motor control unit and power switching elements (Field Effect Transistors or FETs). The combined surfboard PCB is located above the trigger, but below the motor and drive mechanism. In other instances, the combined PCB has a doughnut shape and is located coaxially with a motor shaft. The combined PCB may be positioned between a doughnut-shaped control PCB and the motor.

Abstract: An electric motor includes a rotor assembly including a rotor shaft, a rotor body fixedly coupled to the rotor shaft, and a plurality of magnets coupled to the rotor body. The electric motor also includes a stator assembly at least partially received within the rotor body. The stator assembly includes a stator mount including a stator support portion and a motor support portion. The stator assembly also includes a stator core assembly fixedly supported by the stator mount, the stator core assembly defining a central bore that receives the rotor shaft and the stator support portion. The electric motor also includes a bearing having an outer race and an inner race, the outer race being supported by the stator core assembly, and the inner race supporting the rotor shaft for rotation relative to the stator assembly. The stator core assembly further defines a bearing pocket adjacent to the central bore.

Abstract: An electric motor includes a stator assembly including a lamination stack and a printed circuit board assembly (PCBA) coupled to the lamination stack at an axial end of the stator assembly. The stator assembly also includes a plurality of windings wrapped about the lamination stack to form a plurality of coils. The plurality of windings includes a first winding defining a first coil of the plurality of coils and a second coil of the plurality of coils located opposite from the first coil. The stator assembly further includes a plurality of terminals configured to electrically connect the plurality of windings to the PCBA. The plurality of terminals include a first terminal and a second terminal. The first coil and the second coil are connected in parallel between the first terminal the second terminal.

Abstract: A method of manufacturing a brushless electric motor including providing a stator that includes a core defining a plurality of stator teeth, positioning a rotor within the stator, coupling a stator end cap to an end of the core, winding a plurality of coils on the plurality of stator teeth, and overmolding a plurality of coil contact plates within the stator end cap. The coil contact plates short-circuit diagonally opposite coils on the stator.

Abstract: A power tool with a combined printed circuit board (PCB) that reduces internal wiring of the power tool and provides a large amount of air flow to internal components. In some instances, the combined PCB has a surfboard shape and includes a motor control unit and power switching elements (Field Effect Transistors or FETs). The combined surfboard PCB is located above the trigger, but below the motor and drive mechanism. In other instances, the combined PCB has a doughnut shape and is located coaxially with a motor shaft. The combined PCB may be positioned between a doughnut-shaped control PCB and the motor.

Abstract: Power tools described herein include a housing, a brushless direct current (DC) motor, a non-conductive terminal mount, and a plurality of terminals. The housing has a motor housing portion, a handle portion, and a battery pack interface. The brushless DC motor is located within the motor housing portion and has a rotor and a stator. The non-conductive terminal mount is located on an outer peripheral surface of the stator and includes an angled surface. The angled surface is not substantially parallel to a longitudinal axis of the motor. The plurality of terminals is mounted on the angled surface of the terminal mount. Each of the terminals is angled in a first direction such that the terminals are not substantially parallel to the longitudinal axis of the motor.

Abstract: A power tool with a combined printed circuit board (PCB) having a doughnut shape and located coaxially with a motor shaft. The combined PCB is secured to a heat sink on one end of the motor and a metal end piece is positioned on an opposite end of the motor. The metal end cap and heat sink are secured to one another via fasteners to provide a rigid coupling. A tabbed end piece is provided between the heat sink and the motor stator and is also secured into place via the fasteners. The tabbed end piece includes wire support tabs that provide strain relief to motor coil leads. The wire support tabs extend axially from circumferential locations of the tabbed end piece and include channels to guide the motor coil leads to solder contact points on the combined PCB.

Abstract: A motor assembly for use with a power tool includes a motor housing, a brushless electric motor disposed at least partially in the motor housing, and a PCB assembly coupled to the motor housing. The PCB assembly includes a heat sink, a power PCB coupled to a first side of the heat sink, and a position sensor PCB coupled to a second side of the heat sink opposite the first side and in facing relationship with the motor.

Abstract: An electric motor assembly includes a circuit board, a rotor assembly, and a stator assembly having a first end coupled to the circuit board and a second end opposite the first end. The stator assembly also includes an annular stator body having a plurality of inwardly projecting teeth. The stator assembly further includes windings wrapped about the stator body to form a plurality of coils. The stator assembly also includes a terminal coupled to an outer periphery of the stator body and extending longitudinally between the first end and the second end. The terminal is coupled to the circuit board at the first end and is coupled to the windings at the second end to electrically connect the windings to the circuit board. The terminal is molded to an attachment member, and the attachment member is molded to the outer periphery of the stator body.

Abstract: A method of forming a molded rotor assembly for an electric motor includes providing a lamination stack, molding an insulative material to the lamination stack to form an integral fan and magnet retention coupled to the lamination stack, the lamination stack and the integral fan and magnet retention together forming a rotor body, and pressing a shaft into a central aperture formed in the rotor body to achieve an interference fit between the shaft and the lamination stack.