An electric tool includes: a housing; a motor accommodated in the housing and providing power to a working component, the motor includes a stator including an excitation winding and a rotor including an armature winding, and the excitation winding is connected in series to the armature winding; a first power input unit, capable of connecting to an external AC power source so as to provide an alternating current to the motor; a second power input unit, capable of connecting to a battery component so as to provide a direct current to the motor; and a power source control unit, controlling the motor to obtain power input by using one of the first power input unit and the second power input unit. The electric tool can adapt to an AC power source and a DC power source, and the motor has a simple structure.

An electric tool includes: a housing; a motor accommodated in the housing and providing power to a working component, the motor includes a stator including an excitation winding and a rotor including an armature winding, and the excitation winding is connected in series to the armature winding; a first power input unit, capable of connecting to an external AC power source so as to provide an alternating current to the motor; a second power input unit, capable of connecting to a battery component so as to provide a direct current to the motor; and a power source control unit, controlling the motor to obtain power input by using one of the first power input unit and the second power input unit. The electric tool can adapt to an AC power source and a DC power source, and the motor has a simple structure.

A brush holder has a core side position regulator engaged with a first connection plate to regulate a relative position. The core side position regulator has a projection part projected toward an armature core in the axial direction, and a fitting groove portion defined on both sides of the projection part in a circumferential direction. The relative position in the circumferential direction is regulated by an engagement between the projection part and a slit of the first connection plate. The relative position in the axial direction is regulated by an engagement between sides of the slit and the fitting groove portion. A width of the projection part in the circumferential direction is larger than a width of a brush in the circumferential direction.

A motor assembly includes: a motor housing including: at least one brush receptacle having top and bottom ends; a locking element extending from the top end toward the bottom end; and a housing spring member; at least one brush holder apparatus including: a brush holder housing sized to be received within the brush receptacle, including: an upper surface and a lower surface; a receiving aperture; and an open end; a brush spring enclosed by the brush holder housing; and a brush located inside the brush holder housing; wherein the brush holder apparatus is inserted inside the brush receptacle; and wherein the housing spring member urges the brush holder apparatus toward the top end such that the locking element is received inside the receiving aperture.

A commutated DC motor (10) includes a stator (12) and a rotor (14) mounted in the stator (12). The stator (12) has 2P magnetic poles, wherein P is an integer greater than 1. The rotor (14) includes a rotor shaft (81) with a rotor core (85), and a commutator (83) fixed thereto. The rotor core (85) has multiple teeth defining mP slots therebetween, wherein m is an odd integer greater than 1. The commutator (83) has kmP segments, wherein k is 1 or 2. A rotor winding (87) formed by winding a single continuous wire is received in the slots of the rotor core (85) and connected to the segments of the commutator (83), and has km winding units. Each winding unit includes P coils in series connection and is directly connected to only two segments.

A commutated DC motor (10) includes a stator (12) and a rotor (14) mounted in the stator (12). The stator (12) has 2P magnetic poles, wherein P is an integer greater than 1. The rotor (14) includes a rotor shaft (81) with a rotor core (85), and a commutator (83) fixed thereto. The rotor core (85) has multiple teeth defining mP slots therebetween, wherein m is an odd integer greater than 1. The commutator (83) has kmP segments, wherein k is 1 or 2. A rotor winding (87) formed by winding a single continuous wire is received in the slots of the rotor core (85) and connected to the segments of the commutator (83), and has km winding units. Each winding unit includes P coils in series connection and is directly connected to only two segments.

A motor assembly includes: a motor housing including: at least one brush receptacle having top and bottom ends; a locking element extending from the top end toward the bottom end; and a housing spring member; at least one brush holder apparatus including: a brush holder housing sized to be received within the brush receptacle, including: an upper surface and a lower surface; a receiving aperture; and an open end; a brush spring enclosed by the brush holder housing; and a brush located inside the brush holder housing; wherein the brush holder apparatus is inserted inside the brush receptacle; and wherein the housing spring member urges the brush holder apparatus toward the top end such that the locking element is received inside the receiving aperture.