An asymmetrical, direct current excited brushed motor may include a motor shaft; a commutator with a number of lamellae arranged in the circumferential direction; an armature with a number of armature teeth and armature grooves, where anchor windings are arranged in the armature grooves to form coils; at least one brush pair for supplying the coils with power, including two brushes contacting the lamellae; and a number n of permanent magnets in the stator to form a magnetic field, where n is a multiple of 2 and n>2, and where the number of armature teeth is unequal to a multiple of n. A position angle between the brushes of a brush pair is equal to or less than 90 and unequal to a multiple of the position angle between two directly consecutive lamellae.

A distributed winding arrangement for an electric motor is provided that reduces brush arcing while reducing the size of the commutator. The electric motor is comprised generally of an armature having a plurality of spaced apart posts defining a plurality of spaced apart winding slots; a stator disposed coaxially with the armature; and a commutator having a plurality of commutator bars, where the number of commutator bars is an integer greater than the number of winding slots but less than twice the number of winding slots provided by the armature.

A distributed winding arrangement for an electric motor is provided that reduces brush arcing while reducing the size of the commutator. The electric motor is comprised generally of an armature having a plurality of spaced apart posts defining a plurality of spaced apart winding slots; a stator disposed coaxially with the armature; and a commutator having a plurality of commutator bars, where the number of commutator bars is an integer greater than the number of winding slots but less than twice the number of winding slots provided by the armature.

According to the present invention, a coil is continuously wound in a single pass around each of a series of teeth, and connected to each segment.

According to the present invention, a coil is continuously wound in a single pass around each of a series of teeth, and connected to each segment.

A brush motor includes a stator and a rotor. The rotor includes a rotary shaft with a rotor core and commutator fixed thereto. The commutator includes an insulating base and commutator segments fixed to the insulating base. The stator includes 2P stator poles, where P is an integer greater than 1. The rotor comprises m teeth, where 4P>m>2P, and 2m is an integral multiple of P. The rotor includes a rotor winding, which is a concentrated winding having m first elements and m second elements. Each tooth is wound with one of the first elements and one of the second elements. the m first elements form a plurality of element groups, each having n first elements connected in series, and being connected only to corresponding commutator segments at both ends thereof, where Pn2. Both ends of each second element are connected to corresponding commutator segments.

A brush motor includes a stator and a rotor. The rotor includes a rotary shaft with a rotor core and commutator fixed thereto. The commutator includes an insulating base and commutator segments fixed to the insulating base. The stator includes 2P stator poles, where P is an integer greater than 1. The rotor comprises m teeth, where 4P>m>2P, and 2m is an integral multiple of P. The rotor includes a rotor winding, which is a concentrated winding having m first elements and m second elements. Each tooth is wound with one of the first elements and one of the second elements. the m first elements form a plurality of element groups, each having n first elements connected in series, and being connected only to corresponding commutator segments at both ends thereof, where Pn2. Both ends of each second element are connected to corresponding commutator segments.

A hand held power tool that includes a housing, a power source input configured to receive power from a power source, and a brushed motor located within the housing. The brushed motor is configured to receive power from the power source input. The brushed motor includes a first primary stator pole including a first pole neck and a first pole arc, a second primary stator pole including a second pole neck and a second pole arc, a first stator interpole including a first interpole neck, and a second stator interpole including a second interpole neck. The first stator interpole and the second stator interpole are each positioned between the first primary stator pole and the second primary stator pole.

A hand held power tool that includes a housing, a power source input configured to receive power from a power source, and a brushed motor located within the housing. The brushed motor is configured to receive power from the power source input. The brushed motor includes a first primary stator pole including a first pole neck and a first pole arc, a second primary stator pole including a second pole neck and a second pole arc, a first stator interpole including a first interpole neck, and a second stator interpole including a second interpole neck. The first stator interpole and the second stator interpole are each positioned between the first primary stator pole and the second primary stator pole.

In a 4-pole, 6-slot, 18-segment electric motor, one forward winding coil (91) and two reverse winding coils (92, 93) are wound on each tooth (12). When the forward winding coils are formed of coils corresponding to a U phase, a V phase, and a W phase and the reverse winding coils are formed of coils corresponding to a U phase, a V phase, and a W phase, the coils, which correspond to a U phase, a W phase, a W phase, a V phase, a U phase, a U phase, a W phase, a V phase, and a V phase, are electrically connected in this order between the adjacent segments. When the number of turns of the coils (91) corresponding to a U phase, a V phase, and a W phase is denoted by T1, the number of turns of the coils (92), which correspond to a U phase, a V phase, and a W phase and first come into sliding contact with a brush, is denoted by T2, and the number of turns of the coils (93), which correspond to a U phase, a V phase, and a W phase and later come into sliding contact with the brush, is denoted by T3, T2>T1>T3 is satisfied.