Abstract: A motor is provided that includes magnetic poles, an armature core, armature coils, a commutator, and power supply brushes. The armature core includes teeth arranged in the circumferential direction to extend in a radial pattern. The armature coils include inner layer coils and outer layer coils. Each of the inner layer coils is wound around radially proximal end portions of two circumferentially adjacent teeth or a radially proximal end portion of one of the teeth. The inner layer coils are arranged in the circumferential direction without overlapping each other in the radial direction. Each of the outer layer coils is wound around radially distal end portions of two circumferentially adjacent teeth by distributed winding. The outer layer coils are arranged radially outward of the inner layer coils and are arranged in the circumferential direction without overlapping each other in the radial direction.

Abstract: A motor is provided that includes magnetic poles, an armature core, armature coils, a commutator, and power supply brushes. The armature core includes teeth arranged in the circumferential direction to extend in a radial pattern. The armature coils include inner layer coils and outer layer coils. Each of the inner layer coils is wound around radially proximal end portions of two circumferentially adjacent teeth or a radially proximal end portion of one of the teeth. The inner layer coils are arranged in the circumferential direction without overlapping each other in the radial direction. Each of the outer layer coils is wound around radially distal end portions of two circumferentially adjacent teeth by distributed winding. The outer layer coils are arranged radially outward of the inner layer coils and are arranged in the circumferential direction without overlapping each other in the radial direction.

Abstract: A direct current motor is disclosed. The motor includes a stator, a commutator, an armature core, and brushes. The stator has a yoke and magnetic poles. The magnetic poles are arranged at a predetermined pitch along a circumferential direction of the yoke. The number of the magnetic poles is represented by the expression: 2×P (P is an integer not less than 2). The commutator has segments that are arranged in a circumferential direction of the commutator. The number of the segments is represented by the expression: P×N (N is an odd number not less than 3). The armature core is rotatable integrally with the commutator and includes teeth provided by the number represented by the expression: 2×P×N. A coil is wound around the teeth by distributed winding. Each one of the brushes is pressed against and contacts the segments.

Abstract: A motor has a plurality of excitation coils, a commutator having a plurality of segments, a plurality of supply brushes and a short-circuit line. Each coil is connected to corresponding ones of the segments. The supply brushes include a plurality of supply brushes each having one of an anode and a cathode. At least one supply brush has the other one of an anode and a cathode. The supply brushes each simultaneously contact different one of the segments. The short-circuit line short-circuits segments that simultaneously contact the supply brushes of the same pole. The supply brushes of the same pole separate from the short-circuited segments at different times.

Abstract: A DC motor is provided with a yoke having a polygonal cylindrical shape and an inner wall surface provided with a plurality of consecutive flat surfaces, a plurality of permanent magnets each having a flat plate shape, being fixed on each flat surface on the inner wall surface of the yoke, and an armature arranged rotatably within the yoke. Each permanent magnet has a surface facing the armature. The surface has a rectangle shape provided with a symmetry center. Each permanent magnet is asymmetrical with respect to a line passing through the symmetry center and extending in an axial direction of the yoke. Accordingly, a dimension along the axial direction of the yoke in each permanent magnet decreases toward the outer side from a center part of the permanent magnet.

Abstract: A motor has a plurality of excitation coils, a commutator having a plurality of segments, a plurality of supply brushes and a short-circuit line. Each coil is connected to corresponding ones of the segments. The supply brushes include a plurality of supply brushes each having one of an anode and a cathode. At least one supply brush has the other one of an anode and a cathode. The supply brushes each simultaneously contact different one of the segments. The short-circuit line short-circuits segments that simultaneously contact the supply brushes of the same pole. The supply brushes of the same pole separate from the short-circuited segments at different times.

Abstract: A motor has a plurality of excitation coils, a commutator having a plurality of segments, a plurality of supply brushes and a short-circuit line. Each coil is connected to corresponding ones of the segments. The supply brushes include a plurality of supply brushes each having one of an anode and a cathode. At least one supply brush has the other one of an anode and a cathode. The supply brushes each simultaneously contact different one of the segments. The short-circuit line short-circuits segments that simultaneously contact the supply brushes of the same pole. The supply brushes of the same pole separate from the short-circuited segments at different times.

Abstract: Teeth of a first core sub-part and teeth of a second core sub-part are alternately arranged in a circumferential direction. Each tooth has a tooth main body, which may include two tilted portions at two opposed circumferential ends, respectively, of the tooth main body. Each tilted portion is angled relative to a corresponding direction parallel to the axial direction of the core. Each one of the first and second core sub-parts may have fitting recesses and fitting projections, which are engaged with the fitting projections and the fitting recesses of the other one of the first and second core sub-parts. Each tapered wall surface of each fitting recess is angled relative to a corresponding direction parallel to the axial direction. Similarly, each tapered wall surface of each fitting projection is angled relative to a corresponding direction parallel to the axial direction.

Abstract: An electric motor includes a cylindrical yoke main body and a plurality of permanent magnets having an arcuate cross-section. The permanent magnets are secured to a inner circumferential surface of the yoke main body such that the permanent magnets are continuous with one another along the entire circumference of the yoke main body, thereby forming a ring. An even number of magnetic poles are formed in the permanent magnets at predetermined angular intervals along the circumferential direction of the yoke main body. A pair of the magnetic poles that are adjacent to each other in the circumferential direction of the yoke main body have different magnetic polarities from each other. At least one of the permanent magnets is provided with a section where the magnetic polarity changes in the circumferential direction of the yoke main body. This suppresses vibration excited in a stator that causes vibration and noise.

Abstract: Teeth of a first core sub-part and teeth of a second core sub-part are alternately arranged in a circumferential direction. Each tooth has a tooth main body, which may include two tilted portions at two opposed circumferential ends, respectively, of the tooth main body. Each tilted portion is angled relative to a corresponding direction parallel to the axial direction of the core. Each one of the first and second core sub-parts may have fitting recesses and fitting projections, which are engaged with the fitting projections and the fitting recesses of the other one of the first and second core sub-parts. Each tapered wall surface of each fitting recess is angled relative to a corresponding direction parallel to the axial direction. Similarly, each tapered wall surface of each fitting projection is angled relative to a corresponding direction parallel to the axial direction.

Abstract: Teeth of a first core sub-part and teeth of a second core sub-part are alternately arranged in a circumferential direction. Each tooth has a tooth main body, which may include two tilted portions at two opposed circumferential ends, respectively, of the tooth main body. Each tilted portion is angled relative to a corresponding direction parallel to the axial direction of the core. Each one of the first and second core sub-parts may have fitting recesses and fitting projections, which are engaged with the fitting projections and the fitting recesses of the other one of the first and second core sub-parts. Each tapered wall surface of each fitting recess is angled relative to a corresponding direction parallel to the axial direction. Similarly, each tapered wall surface of each fitting projection is angled relative to a corresponding direction parallel to the axial direction.

Abstract: Teeth of a first core sub-part and teeth of a second core sub-part are alternately arranged in a circumferential direction. Each tooth has a tooth main body, which may include two tilted portions at two opposed circumferential ends, respectively, of the tooth main body. Each tilted portion is angled relative to a corresponding direction parallel to the axial direction of the core. Each one of the first and second core sub-parts may have fitting recesses and fitting projections, which are engaged with the fitting projections and the fitting recesses of the other one of the first and second core sub-parts. Each tapered wall surface of each fitting recess is angled relative to a corresponding direction parallel to the axial direction. Similarly, each tapered wall surface of each fitting projection is angled relative to a corresponding direction parallel to the axial direction.

Abstract: A motor has a plurality of excitation coils, a commutator having a plurality of segments, a plurality of supply brushes and a short-circuit line. Each coil is connected to corresponding ones of the segments. The supply brushes include a plurality of supply brushes each having one of an anode and a cathode. At least one supply brush has the other one of an anode and a cathode. The supply brushes each simultaneously contact different one of the segments. The short-circuit line short-circuits segments that simultaneously contact the supply brushes of the same pole. The supply brushes of the same pole separate from the short-circuited segments at different times.