An armature includes an armature core, teeth, a commutator, concentrated winding wires, and distributed winding wires. Each of the teeth includes a first branch portion and a second branch portion. Each of segments in the commutator has a riser. A start end and a terminal end of the concentrated winding wire are pulled out separately in a direction getting closer to the commutator and in a direction away from the commutator. The conductor between the concentrated winding wires is hooked by the riser by which the conductor between the other concentrated winding wires is not hooked. A start end and a terminal end of the distributed winding wire are pulled out separately in a direction getting closer to the commutator and in a direction away from the commutator. The conductor between the distributed winding wires is hooked by the riser by which at least one of the conductor between the concentrated winding wires and the conductor between the other distributed winding wires is not hooked.

A brush-commutated direct-current motor comprises a stator which is fitted with a plurality of field poles, a rotor which can rotate in relation to the stator about a rotation axis and which has a plurality of pole teeth, a plurality of windings, wherein a plurality of windings are arranged on each pole tooth, a commutator which is arranged on the rotor and has a plurality of lamellas, wherein each winding is connected to one of the lamellas by means of a first winding arm and is connected to another of the lamellas by means of a second winding arm, and a plurality of short-circuiting links which each electrically connect two windings to one another and to this end are each arranged on at least two lamellas of the commutator. The plurality of windings of the plurality of pole teeth are formed by a plurality of wire turns.

A brush-commutated direct-current motor comprises a stator which is fitted with a plurality of field poles, a rotor which can rotate in relation to the stator about a rotation axis and which has a plurality of pole teeth, a plurality of windings, wherein a plurality of windings are arranged on each pole tooth, a commutator which is arranged on the rotor and has a plurality of lamellas, wherein each winding is connected to one of the lamellas by means of a first winding arm and is connected to another of the lamellas by means of a second winding arm, and a plurality of short-circuiting links which each electrically connect two windings to one another and to this end are each arranged on at least two lamellas of the commutator. The plurality of windings of the plurality of pole teeth are formed by a plurality of wire turns.

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.

[Problem] To reduce the size of a linear actuator motor without increasing the operating noise thereof, and to thereby achieve a quieter, more compact linear actuator. [Solution] A linear actuator including: a shaft that is rotated in the forward and reverse directions by a motor via a double start worm and a worm wheel; a screw nut that is screwed and mounted to the shaft; and a piston tube that is fixed to the screw nut and that advances or retreats in accordance with the rotation of the shaft. The motor includes: a four-pole magnet; an armature formed by lap winding an armature coil; a commutator; brushes that are vertically arranged at positions offset by approximately 90; and an equalizer for connecting coils in the armature coil that are to undergo potential equalization.

[Problem] To reduce the size of a linear actuator motor without increasing the operating noise thereof, and to thereby achieve a quieter, more compact linear actuator. [Solution] A linear actuator including: a shaft that is rotated in the forward and reverse directions by a motor via a double start worm and a worm wheel; a screw nut that is screwed and mounted to the shaft; and a piston tube that is fixed to the screw nut and that advances or retreats in accordance with the rotation of the shaft. The motor includes: a four-pole magnet; an armature formed by lap winding an armature coil; a commutator; brushes that are vertically arranged at positions offset by approximately 90; and an equalizer for connecting coils in the armature coil that are to undergo potential equalization.

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 DC commutator motor includes a yoke, a field magnet, and an armature. A shaft is positioned on a central axis of the armature. A plurality of commutator segments is positioned in a circumferential direction of the shaft. A plurality of armature slots is formed on an outer periphery of an armature core. An upper coil is wound the number of turns Na through two armature slots, which are located apart from each other with the predetermined number of armature slots therebetween, at their opening sides. A lower coil is connected in parallel with the upper coil and wound the number of turns Nb through the two armature slots at their bottom sides. The number of turns Na is smaller than the number of turns Nb.

A DC commutator motor includes a yoke, a field magnet, and an armature. A shaft is positioned on a central axis of the armature. A plurality of commutator segments is positioned in a circumferential direction of the shaft. A plurality of armature slots is formed on an outer periphery of an armature core. An upper coil is wound the number of turns Na through two armature slots, which are located apart from each other with the predetermined number of armature slots therebetween, at their opening sides. A lower coil is connected in parallel with the upper coil and wound the number of turns Nb through the two armature slots at their bottom sides. The number of turns Na is smaller than the number of turns Nb.