Abstract: Coils are provided on a plurality of tooth sections of a core. The coils are formed by successively winding a conductor on the tooth sections with at least one tooth section between each successive windings, such that each portion of the conductor extending between two tooth sections located with at least one tooth section therebetween forms a jumper wire extending in the circumferential direction of the core. A commutator has a plurality of claw portions projecting to the outside of the commutator. Each of the claw portions electrically connects one of a plurality of segments to one of the jumper wires. When the core and the commutator are attached to a rotary shaft, each claw portion is arranged at a position corresponding to one of the jumper wires as viewed in the axial direction of the rotary shaft.

Abstract: A short-circuit member assembly for short-circuiting a plurality of segments arranged in a circumferential direction is disclosed. The short-circuit member assembly includes first and second short-circuit member groups that are superimposed with each other. The first short-circuit member group includes m first terminals, which are superimposed and joined with m first terminals included in the second short-circuit member group to form m first-terminal joint portions. The m first-terminal joint portions and the remaining first terminals in the short-circuit member groups are arranged in the circumferential direction and connected to the segments. All of the second terminals in the first short-circuit member group are superimposed and joined with all of the second terminals included in the second short-circuit member group.

Abstract: A commutator main body has a cylindrical insulating body, and a plurality of segments arranged in an outer circumference of the insulating body. A short-circuit member is arranged in an end in an axial direction of the insulating body. The short-circuit member has a plurality of first short-circuit pieces and a plurality of second short-circuit pieces. A tabular insulating portion covers first coupling portions of the first short-circuit pieces, and second coupling portions of the second short-circuit pieces. The insulating portion has a restriction recess, and the end in the axial direction has a restriction projection. The restriction projection is engaged with the restriction recess, whereby the movement of the short-circuit member in the circumferential direction with respect to the commutator main body is restricted. Accordingly, the assembly of the short-circuit member in the commutator main body is facilitated.

Abstract: In a direct current electric motor, segment pieces of a commutator are generally planar and are arranged one after another in a circumferential direction about a rotational axis of the commutator. A slidably engaging surface of each segment piece, which is slidably engageable with a plurality of brushes of the motor, extends in a plane that is generally perpendicular to the rotational axis, and each segment piece includes a radially inner engaging portion at a radially inner end part of the segment piece. Each conductive line extends along a corresponding straight line and electrically interconnects between the radially inner engaging portions of corresponding two of the plurality of segment pieces to implement the same electric potential in the corresponding two of the plurality of segment pieces.

Abstract: A stator has four or more magnetic poles. A commutator has a plurality of segments arranged in the circumferential direction and a short-circuit conductor for short-circuiting predetermined segments from among these segments. Each segment has an angular width WS, and there is a gap of an angular width WU between the segments. A substantial angular width WB of each of an anode brush and a cathode brush satisfies (n?1)(WS+WU)+WU<WB<n(WS+WU)+WU, where n is an integer no less than two. A plurality of coils are each connected to the corresponding one of the segments in order to form n closed loops. The closed loops each pass through the corresponding segments and are electrically independent of each other.

Abstract: A stator of a direct current motor includes six magnetic poles. An armature of the direct current motor includes an armature core having eight slots, a plurality of windings wound around the armature core as concentrated windings, and a commutator having twenty-four segments connected to the windings. The plurality of windings are connected to one another to form a single closed loop. The direct current motor further includes an anode power supply brush and a cathode power supply brush that slidably contact the segments. The aspect ratio, which is the ratio of the diameter of the armature core with respect to the length in the axial direction of the armature core is set to a range of 3.2 through 5.6. This increases the constraint torque/mass ratio of the direct current motor.

Abstract: Ferromagnetic bodies, the number of which is n (n is an integer greater than or equal to two), are secured to an inner circumferential surface of a cylindrical yoke. A first gap S1 is provided between ferromagnetic bodies that are adjacent to each other in the circumferential direction. Active magnetic poles, the number of which is m (m is an integer greater than or equal to two), apply magnetic fields to each ferromagnetic body from radially inside. As a result, each magnet has magnetic pole portions the number of which is m. A third gap is provided between each pair of the active magnetic poles that correspond to a common ferromagnetic body. The angular width of the third gap is set greater than a first angular width of the first gap. As a result, all magnetic pole centers are easily arranged at equal angular intervals.

Abstract: A motor includes an annular armature core, a cylindrical yoke, and a permanent magnet that is fixed to the yoke in such a manner as to face the armature core in the radial direction. A plate-like magnetism guiding portion is located between the armature core and the permanent magnet. The magnetism guiding portion is made of a soft magnetic material, and has a first surface facing the permanent magnet and a second surface facing the armature core. With respect to the axial direction of the motor, the length of the first surface is equal to that of the permanent magnet, and the length of the second surface is less than that of the first surface With respect to the axial direction of the motor, the length of the permanent magnet is greater than that of the armature core.

Abstract: An insulator is mounted in an armature core. Coils are wound around teeth of the armature core by way of concentrated winding. A power feeding member, which supplies a current to the coils, includes a connecting portion. A separating portion, which is provided in the insulator, is located in the teeth. The separating portion separates each of the coils to a first portion and a second portion. The connecting portion is electrically connected to the first portion. Accordingly, while preventing damage to the coils, the coils are easily connected to the power feeding member.

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 stator of a direct current motor includes six magnetic poles. An armature of the direct current motor includes an armature core having eight slots, a plurality of windings wound around the armature core as concentrated windings, and a commutator having twenty-four segments connected to the windings. The plurality of windings are connected to one another to form a single closed loop. The direct current motor further includes an anode power supply brush and a cathode power supply brush that slidably contact the segments. The aspect ratio, which is the ratio of the diameter of the armature core with respect to the length in the axial direction of the armature core is set to a range of 3.2 through 5.6. This increases the constraint torque/mass ratio of the direct current motor.

Abstract: The armature of a motor comprises a core constituted by assembling a plurality of split core members. Each split core member has at least two teeth. The method for manufacturing the armature comprises the steps of: winding a conductive wire on each tooth of each split core member to form a first coil on the teeth; spanning the conductive wire extending from a winding finishing end of the first coil from each tooth to the other tooth; winding the conductive wire on the tooth to which the conductive wire is spanned to form a second coil on the first coil; joining a winding starting end of the first coil and a winding finishing end of the second coil in each tooth to form a single coil; and mutually assembling the plurality of split core members each comprising the coils. As a result, productivity is improved, while reducing size.

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: Coils are provided on a plurality of tooth sections of a core. The coils are formed by successively winding a conductor on the tooth sections with at least one tooth section between each successive windings, such that each portion of the conductor extending between two tooth sections located with at least one tooth section therebetween forms a jumper wire extending in the circumferential direction of the core. A commutator has a plurality of claw portions projecting to the outside of the commutator. Each of the claw portions electrically connects one of a plurality of segments to one of the jumper wires. When the core and the commutator are attached to a rotary shaft, each claw portion is arranged at a position corresponding to one of the jumper wires as viewed in the axial direction of the rotary shaft.

Abstract: A method for winding a wire in a rotating electric machine provided with an armature including a plurality of core members. Each core member has two teeth arranged at an interval of 180 degrees. A connecting portion and an annular portion connect the two teeth. The core members are joined together so that the teeth extend radially. The wire is wound around each tooth of the armature. The method includes separating a tooth from an adjacent tooth when the core members are joined together, and winding a wire around the separated tooth.

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: 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: The armature of a motor comprises a core constituted by assembling a plurality of split core members. Each split core member has at least two teeth. The method for manufacturing the armature comprises the steps of: winding a conductive wire on each tooth of each split core member to form a first coil on the teeth; spanning the conductive wire extending from a winding finishing end of the first coil from each tooth to the other tooth; winding the conductive wire on the tooth to which the conductive wire is spanned to form a second coil on the first coil; joining a winding starting end of the first coil and a winding finishing end of the second coil in each tooth to form a single coil; and mutually assembling the plurality of split core members each comprising the coils. As a result, productivity is improved, while reducing size.