Abstract: Provided is a commutator of a motor including a body and hooks forming coil-receiving spaces between the body and inner surfaces of the hooks, wherein the hooks include recesses concavely formed on the inner surfaces of the hooks, and coils are seated on the recesses. Thus the present disclosure provides an advantageous effect of increasing fixing force of the hooks.

Abstract: A method of fabricating an armature for a motor includes providing a laminated assembly having a length, a central axis, and a plurality of open slots each extending the length and each configured to locate one conductor at a first greater radial distance from the central axis and another conductor at a second lesser radial distance from the central axis. A first conductor is inserted into a first one of the slots at the greater radial distance such that the first conductor extends out of the first one of the slots. A free end of the inserted first conductor is bent in each of a first direction and a second direction orthogonal to the first direction. A second conductor is inserted into a second one of the slots at the lesser radial distance such that the second conductor extends out of the second one of the slots. A free end of the inserted second conductor is bent in each of the two orthogonal directions.

Abstract: A commutator is formed by providing an electrically insulating commutator body. First and second areas are defined on the commutator body covering a brush contact surface in an alternating manner. At least the surfaces of the first areas are formed of laser direct structured material. The first areas are treated by a laser to form metal particle layers. Conductive layers are formed on the metal particle layers by a plating process to form commutator segments. Terminals are connected to the conductive layers for connecting the commutator to rotor windings.

Abstract: A commutator has a plurality of commutator segments fixed to an insulating support member. The commutator segments are formed by cold or hot forming a copper billet cut from a length of copper wire. Each billet has a volume approximately equal to the volume of one commutator segment. Each commutator segment has a main body and an anchor integrally formed with the main body. The commutator segments are spaced about a circle and then an insulating support member is molded to the commutator segments to fix the commutator segments to the support member.

Abstract: A dc motor includes a stator having multiple field magnet poles, and an armature having an armature core, armature coils, and a commutator, and brushes brought into contact with the commutator. The armature coils include concentrated winding coil units wound on respective teeth, and connecting wire units that electrically connect each of the concentrated winding coil units together. A segment group of the commutator includes a first segment and a second segment placed adjacent to each other, to which the concentrated winding coil units are connected, the segment group also includes a third segment disposed next to the adjacent placement, and only the connecting wire unit is connected to the third segment. The connecting wire units include connecting wire units that pass through slots and connect each of the concentrated winding coil units together.

Abstract: A commutator motor is configured such that an armature includes an armature core having teeth and slots, an armature coil, and a commutator having segments. The armature coil includes coil units in which windings are wound on the teeth, and jumper wire units for interconnecting between the coil units. Segment group includes first and second segments to which the coil units are connected, and a third segment to which only the jumper wire unit is connected. The first and second segments are disposed adjacent to each other, and the third segment is disposed next to the adjacent arrangement. The configuration includes the jumper wire unit that is wired from the third segment such that each of one part of the wire unit running to one side and the other part of the wire unit running to the other side is wired to pass through the same slot to interconnect between the coil units.

Abstract: In a direct-current motor armature 3 corresponding to an 8-pole-10-slot-20-segment or 12-pole-15-slot-30-segment, a connection wire 25 for short-circuiting segments 14 having the same degree of electric potential is provided to a commutator, a coil 12 is connected electrically to the segments 14 having a potential difference that is equal to a potential difference between the adjacent segments 14, and the coil 12 is wound around teeth 9 to form armature coils 7. Accordingly, an armature for use in a direct-current motor, a direct-current motor, and a method for winding wires around the armature of the direct-current motor for enabling down-sized direct-current motors having extended product life and enhanced performance can be provided.

Abstract: A rotating electrical machine having a shaft, an iron core having slots, an armature winding inserted into the slots, a commutator provided to the shaft and having a plurality of commutator segments that should have same potential. An equalizer connected at one end to a commutator segment among the commutator segments where the commutator segment is in contact with a brush reaches a rear side of the iron core by passing through a slot positioned at a center of a magnetic pole of the rotating electrical machine and returns to the front side by passing through another slot positioned at a center of another magnetic pole so that the equalizer is connected at the other end to a commutator segment where the commutator segment is in contact with a brush of a same polarity as the firstly-mentioned brush.

Abstract: A carbon commutator, for an electric motor, has a plurality of segments forming a brush contact surface and a hub supporting the segments. Each segment has a connector having a terminal for connection of a lead wire, a carbon layer forming the brush contact surface, and a connecting layer fixed to the carbon layer and electrically connecting the carbon layer to the connector. A plurality of micro structures is formed at the interface between the connecting layer and the carbon layer.

Abstract: A multipolar motor is simply wire-wound and an output thereof is capable of being switched. The motor includes at least 8 magnetic poles, an armature including at least 10 tooth sections; a commutator including at least 20 commutator segments, and brush-sets including 2 positive electrode brushes and 2 negative electrode brushes. A hook-holding section arranged to hook-hold conductor wires is installed on each of the commutator segments. Further, a group of coils is defined by using a single conductor wire that is wound onto each of the plurality of tooth sections and hooked onto the plurality of hook holding sections. This motor can switch the state in which the brush-set is energized.

Abstract: The invention relates to a method for producing the rotor winding of an electrical machine having at least four exciter poles in the stator (11) and having a commutator rotor (13) with a number of slots (N) and pole teeth (Z) which deviates from the number of exciter poles, and having a number of individual tooth coils (S) and laminations (L) which is at least twice as high as the number of pole teeth, wherein the individual tooth coils are wound, starting from the first coil (S1) onto in each case that pole tooth with the lowest angular error (Wf) in relation to a pole division (Pt).

Abstract: A commutator includes a cylindrical insulator and commutator pieces, which are formed on the outer circumferential surface of the insulator and arranged side by side in the circumferential direction of the insulator. The commutator pieces are each composed of a conductive plate material, and each includes a connection claw and an engagement claw. The connection claw extends outward in the radial direction of the insulator while being configured to electrically being connected to an armature coil. The engagement claw extends inward in the radial direction of the insulator and engages with the insulator. The commutator pieces each include a recess portion with an undercut formed in a surface facing inward in the radial direction of the insulator.

Abstract: Disclosed herein are an armature for fuel pumps and a manufacturing method thereof, in which a polymer coating film is formed on an armature core such that the armature has corrosion resistance to an alcohol fuel and to a highly corrosive fuel.

Abstract: A motor 10 includes: a yoke on whose inner surface a four-pole magnet is attached; a gear case 15 jointed to an opening portion of the yoke and storing a speed-reduction mechanism; a brush holder 30 stored in an opening portion 15a of the gear case and having a through hole 31 penetrated by a commutator 23 attached to an armature shaft 21 in a center of the brush holder; and a first brush 36, a second brush 35, and a third brush 37 which are stored so as to freely come in and out to/from three brush storing portions 32, 33, and 34 formed so as to interpose the through hole 31 in the brush holder 30. In the motor, the second brush 35 is arranged at a position shifted from the first brush 36 in a rotational direction by 90 degrees, and a third brush 37 is arranged within an included angle opposite to an included angle formed by the first brush 36 and the second brush 35.

Abstract: A commutator motor has a stator, brushes and a rotor. The rotor has a shaft, a rotor core fixed to the shaft, a number of coils wound about the rotor core and a commutator fixed to the shaft next to the rotor core. The commutator has a base and a number of commutator bars fixed to the base in sliding contact with the brushes. The rotor core includes a number of pole bodies extending substantially radially outwards. Each pole body includes a connecting surface at an axial end of the rotor core. The commutator base includes a number of connecting arms extending substantially radially outwards and contacting the connecting surfaces of corresponding pole bodies. At least two of the coils are wound around a corresponding pole body and the connecting arm contacting the connecting surface of this pole body.

Abstract: A brush motor includes a stator and a rotor. The stator includes multiple magnets attached to an inner surface of a stator housing and a brush assembly fixed relative to the housing. The rotor includes a rotor core and a commutator located in a receiving space defined by a mounting portion and an annular sidewall of the rotor core. The commutator includes multiple conductive segments, each of which has a leg penetrating the rotor core and connected with windings on the rotor core.

Abstract: The invention relates to a commutator for an electrical machine, having a commutator body on the outer circumference of which a plurality of electrically conductive, elongated laminations are disposed parallel to the longitudinal axis of the commutator. The laminations disposed adjacent to one another are electrically insulated from one another. The ends of the laminations, oriented toward the wire windings of an armature, are each electrically conductively connected to at least one wire end. According to the invention, it is provided that the ends of the laminations end, perpendicular to the longitudinal axis of the commutator, in planes offset from one another.

Abstract: A commutator includes a first body and a second body which are separately made of electrically insulating material, a plurality of commutator segments fixed on an outer surface of the first body and a plurality of commutator terminals. The first body is a hollow cylinder with two opposite ends. Each terminal has a contact area for contacting a corresponding one of the commutator segments. The second body has a base and a ring wall extending from the base, and one end of the first body is received in a space defined by the base and the ring wall, with the contact area of each terminal being in tight contact with the corresponding commutator segment at the inner side of the ring wall.

Abstract: The invention relates to a method and device for producing an electric machine, an electric machine with a commutator, having commutator hooks for fixing electric wire windings with solder arranged between the commutator hooks and the wire winding and two electrodes arranged adjacent to each other which are pressed against the commutator hooks. An electric current is passed through the commutator hooks by means of electrodes such that the solder melts and forms a connection to the wire winding.

Abstract: The invention relates to a commutator with contact segments, arranged at a distance from each other and forming a brush running surface. Each contact segment is soldered to a securing portion of a metal segment support piece. The commutator has a hub body made from an electrically insulating material which supports the segment support pieces which are each provided with a winding connector hook. According to the invention, at least one solder barrier recess is provided in the upper side of the securing portion facing the contact segment and/or in the under side of the contact segment facing the securing portion.

Abstract: An arrangement having at least two generator bars for a stator of an electrical generator which are electrically connected to one another via a respective bar end is characterized, according to the invention, by the fact that the respective bar ends, which are electrically connected to one another, of the at least two generator bars are braced with respect to one another by means of a tape.

Abstract: There is provided a rotating electric machine capable of reducing torque pulsation, even when a slight stepped portion is present in an inner diameter shape of a stator core formed by allowing coupling split cores divided in every magnetic pole to be in an annular shape. The stator core is formed by stacking a plurality of laminates prepared by stack of coupling split core members formed by punching steel sheets in an annularly arranged shape in a state where the laminates are rotated one another by a predetermined angle. With such a configuration, it is possible to mutually offset torque pulsation components caused by the shape asymmetry of the laminates and reduce the torque pulsation components of the stator core on the whole.

Abstract: A multipolar motor is simply wire-wound and an output thereof is capable of being switched. The motor includes at least 8 magnetic poles, an armature including at least 10 tooth sections; a commutator including at least 20 commutator segments, and brush-sets including 2 positive electrode brushes and 2 negative electrode brushes. A hook-holding section arranged to hook-hold conductor wires is installed on each of the commutator segments. Further, a group of coils is defined by using a single conductor wire that is wound onto each of the plurality of tooth sections and hooked onto the plurality of hook holding sections. This motor can switch the state in which the brush-set is energized.

Abstract: A piezoelectric thin film resonant element includes a resonant portion having a laminate structure made up of a lower electrode, an upper electrode and a piezoelectric film arranged between these two electrodes. The lower electrode has an ellipsoidal plan-view shape and an outer circumference formed with an inclined portion inclined at an angle (about 30° for example) lying within a range of 25° through 55°. The upper electrode has an ellipsoidal plan-view shape. An additional film is provided on the upper electrode at a portion corresponding to the inclined portion of the lower electrode.

Abstract: A DC motor 12, has a stator housing 16 accommodating a permanent magnet stator and a rotor 15 rotatably mounted confronting the stator. The rotor 15 has a shaft 21, a rotor core 22 fitted to the shaft and having laminations forming salient poles or teeth 27. A commutator 23 is fitted to the shaft adjacent one end of the rotor core and windings 24 are wound about the teeth and terminated on segments of the commutator 23. The windings is formed by a number of coils with each coil being wound around a single tooth of the rotor and each tooth supporting a single coil. Brush gear comprising a plurality of brushes 26 in sliding contact with the commutator 23, transfers electrical power to the windings.

Abstract: A commutator 10 for an electric motor comprises a plurality of commutator segments supported by a base. The segments have an electrically conductive body portion 14 and at least one electrically conductive foldable tang 16 provided on the body portion 14 for engaging a winding lead wire 44 of an electric motor. The foldable tang 16 has a proximal end 18 on or adjacent to the body portion 14, and a distal end 22 remote from the proximal end 18. A wire-accommodating portion 30 is provided on or adjacent to the foldable tang 16, so that, when the tang 16 is folded, the wire-accommodating portion provides a predetermined gap 56 for the winding lead wire 44.

Abstract: The present invention relates to a method for producing a rotor of a commutator motor, particularly in a direct current design, comprising a stator having a plurality of stator poles, wherein the rotor comprises a plurality of armature teeth which are disposed on the circumference of the rotor having interposed rotor grooves, and a commutated, which has a plurality of disks and associated winding hooks, comprising the following steps: winding bridges of the commutated by connecting winding hooks of the disks of the commutated, winding windings of armature teeth, and connecting the respective winding ends to winding hooks of the disks of the commutator. The invention further relates to such a commutated motor, particularly in a direct current design, and to an anti-lock breaking device.

Abstract: The claw-pole-rotor shaft has a front end with a radially larger-sized section, two knurled regions known as crimping regions, intended to be assembled with the claw-pole rotor by local deformation of the material of the claw-pole rotor, and a centring region for centring the claw-pole rotor, the crimping regions being positioned on each side of the centring region while the centring region projects radially with respect to the crimping regions of the shaft, these themselves projecting radially with respect to the section of larger radial size at the front end of the shaft. The claw-pole rotor is characterized in that it is equipped with such a shaft while the rotary electrical machine is characterized in that it is equipped with such a rotor.

Abstract: Disclosed is a motor in which a commutator (10) is provided with connecting wires which short-circuit equipotential segments; brushes (21) are constituted by a low-speed brush (21a), a high-speed brush (21b), and a common brush (21c) used in common by the low-speed and high-speed brushes, and are juxtaposed along the circumferential direction. The circumferential brush width (W2) of the high-speed brush is set to be smaller than the circumferential brush width (W1) of the low-speed brush. The high-speed brush and the low-speed brush are formed so that simultaneous sliding contact with equipotential segments (15) can be avoided. Additionally, armature cores (8) are provided such that a plurality of teeth (12) is point-symmetrical about a rotary shaft (3) at equal intervals in the circumferential direction, and the teeth and slots (13) are formed so as to exist alternately at intervals of 90 degrees in the circumferential direction.

Abstract: A slip ring module (76) for a rotor (40) of an electrical machine (10), in particular, an alternator is disclosed, comprising at least one first slip ring (79) with at least one first connecting conductor (103) held in sections of an insulation material (101) for the slip ring module (76), in electrically conducting connection with at least one first slip ring (79) and with an end (115) of the connection conductor (103), facing away from the first slip ring (79), provided for connection to an excitation coil (61). The invention is characterised in that the slip ring module (76) has a further formed conductor (139) forming a direct electrical connection from the first connection conductor (103) to a surface (142) of the slip ring module (76). An electric machine is also provided, in particular, an alternator for motor vehicles, comprising a rotor (40), supporting an excitation coil (61), said slip ring module (76) providing the power supply to the excitation coil (61).

Abstract: A brush holder having brush holding portions and coil holding portions is disclosed. Each brush holding portion holds a brush such that the brush is slidable on a commutator attached to a rotary shaft. Each coil holding portion holds a choke coil electrically connected to one of the coils. The brush holder includes a holder base member and brush holding members that are assembled to the holder base member so as to form the brush holding portions. Each brush holding member includes a coil supporting portion, which forms the coil holding portion between the corresponding brush holding member and the holder base member.

Abstract: The invention relates to a commutator for an electrical machine, having a commutator body on the outer circumference of which a plurality of electrically conductive, elongated laminations are disposed parallel to the longitudinal axis of the commutator. The laminations disposed adjacent to one another are electrically insulated from one another. The ends of the laminations, oriented toward the wire windings of an armature, are each electrically conductively connected to at least one wire end. According to the invention, it is provided that the ends of the laminations end, perpendicular to the longitudinal axis of the commutator, in planes offset from one another.

Abstract: A brushless slip ring has a first conductive rotating member, and a second conductive non-rotating member that is positioned a predetermined distance away from the first conductive rotating member. A conductive semi-solid material electrically couples the first conductive rotating member to the second conductive non-rotating member. The semi-solid material is configured to transfer electric current from the rotating member to the non-rotating member.

Abstract: The present invention is used with a stopper mechanism for mechanically stopping the rotation of a motor. A pair of brushes is disposed such that a line which passes through the center of a rotor and connects the centers of the paired brushes is offset by a predetermined angle from a line which connects the centers of paired magnets. A commutator is disposed in such a manner as to be offset from a reference position by the same angle as the predetermined angle by which the paired brushes are offset. The predetermined angle falls within a range between an angle obtained by dividing 70° by the number of pairs of stator poles and an angle obtained by dividing 290° by the number of pairs of stator poles. Specifically, in the case of two stator poles, the predetermined angle falls within a range of 70° to 290° inclusive. In the case of four stator poles, the predetermined angle falls within a range of 35° to 145° inclusive.

Abstract: A motor 10 includes: a yoke on whose inner surface a four-pole magnet is attached; a gear case 15 jointed to an opening portion of the yoke and storing a speed-reduction mechanism; a brush holder 30 stored in an opening portion 15a of the gear case and having a through hole 31 penetrated by a commutator 23 attached to an armature shaft 21 in a center of the brush holder; and a first brush 36, a second brush 35, and a third brush 37 which are stored so as to freely come in and out to/from three brush storing portions 32, 33, and 34 formed so as to interpose the through hole 31 in the brush holder 30. In the motor, the second brush 35 is arranged at a position shifted from the first brush 36 in a rotational direction by 90 degrees, and a third brush 37 is arranged within an included angle opposite to an included angle formed by the first brush 36 and the second brush 35.

Abstract: A fuel pump includes a pump portion for pumping fuel. The fuel pump further includes a magnet having magnetic poles circumferentially alternate with each other. The fuel pump further includes an armature on a radially inside of the magnet. The armature includes a rotor core provided with a coil formed of a wire. The armature is rotatable for driving the pump portion. A commutator, which is in a substantially disc shape, is provided to an axial end of the armature for rectifying electricity supplying to the coil. The rotor core has an axial end having an outer circumferential periphery defining a commutator-side collar portion extending toward the commutator. The coil is formed by winding the wire between an outer circumferential periphery of the commutator and the commutator-side collar portion.

Abstract: A short-circuit member includes a short-circuit conductor and a short-circuit insulator. The short-circuit conductor includes superimposed first and second short-circuit member formation groups. Each of the short-circuit member formation groups has outer terminals, inner terminals, and linking portions. The outer terminals contact one another and the inner terminals contact one another between each of the short-circuit member formation groups. The linking portions are maintained in non-contact between each of the short-circuit member formation groups.

Abstract: Stable electrical connections between coils and a commutator are realized without causing slackening of the coils wound on individual magnetic teeth. An armature of a rotary motor includes an armature core structured splittably into magnetic tooth members which are individually wound by concentrated-winding type coils, and a commutator having the same number of segments as the number of the magnetic tooth members, the individual segments having connecting terminals, wherein an end portion of the coil concentratedly wound on one of the magnetic tooth members is connected generally in a straight line to the connecting terminal of the segment which is located at a position offset in a circumferential direction by a specific angle from the aforementioned one magnetic tooth member, and a conductor line connected to the connecting terminal of the segment is concentratedly wound on another magnetic tooth member adjacent to the aforementioned one magnetic tooth member.

Abstract: A commutator has an electrically non-conductive base and a plurality of commutator segments fixed to the base. Each segment comprises an electrically conductive connector and a segment part, wherein the connector has a segment portion, a terminal portion and anchors all formed as a monolithic construction. The terminal and anchors extend from the segment portion at radial ends thereof. The anchors fix the connectors to the base by being embedded therein. The segment part is a part of an annular disc forming an electrically conductive brush-contacting layer fixed to a side of the segment portion remote from the base. The segment portions are circumferentially separated by slits into which the base extends and the segment parts are separated circumferentially by slots. The slots are aligned with the slits, are narrower than the slits and extend axially into the material of the base within the slits between adjacent connectors.

Abstract: The invention relates to a method and device for producing an electric machine, an electric machine with a commutator, having commutator hooks for fixing electric wire windings with solder arranged between the commutator hooks and the wire winding and two electrodes arranged adjacent to each other which are pressed against the commutator hooks. An electric current is passed through the commutator hooks by means of electrodes such that the solder melts and forms a connection to the wire winding.

Abstract: An armature where at least one of a first winding wire and a second winding wire is wound around slots that are opposed to all magnetic poles serving as a same magnetic pole in a predetermined winding direction so as to correspond to a predetermined winding number as a total winding number between respective slots, so that the plurality of coils are formed, and a slot from which the first winding wire is led out and a slot into which the second winding wire is led are located circumferentially at both sides of commutator segments with which the first winding wire and the second winding wire are conductive.

Abstract: In a rotating machinery having armature windings constituted by a lot of strands, when the armature winding is constituted by four layers, a step number of the strands becomes half with respect to two layers of armature windings so as to facilitate manufacturing an armature winding of 540 degree transposition in which a transposition pitch is elongated and a circulating current loss is reduced, but since an output voltage becomes twice, for securing a voltage limit value caused by an isolation resisting force, one layer of armature windings are constituted by sub windings separated into at least two layers in a vertical direction, a transposition is independently applied to each of the sub windings, the sub windings are connected to the armature windings of the other slot while keeping an isolation of the sub winding at an armature winding end region by at least two connecting methods, and the sub winding constructs a parallel circuit by the armature windings of a plurality of slots.

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: An electric motor includes an armature core, a commutator including a plurality of commutator segments, a neck disposed between the armature core and the commutator, and a plurality of wires each connected between two adjacent commutator segments and wound around the armature core via the neck. The wires include a first wire connected between first two adjacent commutator segments and a second wire connected between second two adjacent commutator segments positioned opposite to the first two adjacent commutator segments with respect to the axis of the armature core. The first wire and the second wire extend along the neck such that they do not contact with each other.

Abstract: A commutator (10) includes a core (12) having a generally annular periphery (15). A plurality of commutator bars (14) is provided in a spaced relation about the periphery of the core. At least two of the commutator bars have a width different from each other.

Abstract: The invention relates to a commutator with contact segments, arranged at a distance from each other and forming a brush running surface. Each contact segment is soldered to a securing portion of a metal segment support piece. The commutator has a hub body made from an electrically insulating material which supports the segment support pieces which are each provided with a winding connector hook. According to the invention, at least one solder barrier recess is provided in the upper side of the securing portion facing the contact segment and/or in the under side of the contact segment facing the securing portion.

Abstract: A commutator having a plurality of segments, a short-circuit member assembly, a holding portion, and a plurality of spacing members is disclosed. The short-circuit member assembly includes a plurality of short-circuit pieces. Each short-circuit piece has an outer terminal, an inner terminal arranged radially inward from the outer terminal and circumferentially offset from the outer terminal at a predetermined offset angle, and a connecting portion connecting the inner terminal to the outer terminal. The holding portion covers the segments and at least a portion of the short-circuit member assembly to hold the segments and the short-circuit member assembly. The spacing members each have an insulated support portion and a plurality of insulated spacing projections formed integrally with the support portion. Each support portion extends in a radial direction of the short-circuit member assembly.

Abstract: In a rotary electric machine, coils to be wound around an armature are wound so as to have a good magnetic balance. In a rotary electric machine formed with four poles, ten slots, and twenty commentator segments, a pair of coils that respectively conduct an electric current to the commutator segments adjoining an arbitrary commutator segment at both sides in the circumferential direction are caused to face permanent magnets, that are adjoining poles, to be poles opposite from each other, and one coil is wound in a normal winding state, and the other coil, in a reverse winding state.

Abstract: The invention relates to an electrical machine (10), and to a method for producing such an electrical machine, especially for adjusting mobile parts in a motor vehicle. Said machine comprises a rotor (20) on which a bipolar electrical winding (25) having a plurality of coils (26) is arranged. Said coils (26) are configured to give two symmetrical coil sections (27) each which are disposed symmetrical to each other relative to the axis of rotation (23) of the rotor (20), both coil sections (27) being simultaneously commutable.

Abstract: A rotary electric machine and a commutator for the rotary electric machine are disclosed wherein the commutator includes an insulating member carrying thereon a plurality of commutator segments each having a brush contact surface. Each commutator segment has an embedded portion formed with a tab tail, molded to the insulating member, and has a riser portion radially extending outward from the brush contact surface to be electrically connected to armature coils. The insulating member has a large diameter portion and an increased wall thickness portion, axially extending from the large diameter portion in a direction away from the riser portion, with a sum of axial wall thicknesses of the increased wall thickness portion and the large diameter portion lying in a value two times an axial wall thickness of the riser portion. The increased wall thickness portion is formed in a tapered shape.