Abstract: A stator which may be employed in an electric rotating machine. The stator includes a stator winding which includes in-slot portions disposed in slots of a stator core. The in-slot portions are arrayed in each of the slots in a form of multiple layers aligned in a radial direction of the stator core. The stator winding is made up of a first winding and a second winding which are connected together through a joint. The first winding is defined by a portion of the stator winding between the joint and an end of the stator winding which is to be connected to an external. The second winding includes the in-slot portion placed within at least one of the slots as an outermost layer that is one of the layers placed most outwardly in the radial direction of the stator core. This results in a great decrease in leakage current.

Abstract: A rotor of a synchronous motor includes a rotating shaft, a plurality of segments, a plurality of permanent magnets, and a field coil. The segments are located radially outward of the rotating shaft and arranged in the circumferential direction of the rotating shaft at a predetermined pitch with spaces formed therebetween. Each of the segments has a recess making up a magnetic reluctance portion and an opposite pair of ends making up salient-pole portions. Each of the permanent magnets is disposed in one the spaces between the segments with a predetermined orientation of its N and S poles. The field coil is wound around the segments to extend in the circumferential direction of the rotating shaft through the recesses of the segments. The field coil creates, when energized with DC current, magnetic flux which magnetizes the pair of ends of each of the segments in opposite directions.

Abstract: A stator includes a stator-core having slots and teeth, and a back-yoke having convex and concave portions. The convex portions are partially inserted into the slots, and the concave portions receive the teeth. The teeth include tip portions whose circumferential widths become larger along a radial direction from the inside to the outside of the stator. The back-yoke includes convex portions whose circumferential widths become larger along the radial direction from the outside to the inside of the stator. The tip portions and the convex portions have substantially the same shape. The length of a joint portion between the tip portion and the convex portion, the circumferential width of the tooth corresponding to a tip surface of the convex portion, the width of a root portion of the tooth, and the circumferential width of the convex portion corresponding to a bottom face of the concave portion are substantially the same.

Abstract: The Lundell motor apparatus includes a controller for controlling a field current passed to a field coil of a Lundell-type rotor of a motor and an armature current passed to a stator coil of the motor in order to generate a required torque. When the field current is If, the armature current is Ia, a d-axis inductance is Ld, a q-axis inductance is Lq, a q-axis current as a q-axis component of the armature current is Iq, a d-axis current as a d-axis component of the armature current is Id, a field torque is Tf, a field flux is ?f, a reluctance torque is Tr, and a combined torque of the field torque and the reluctance torque is ?T, the controller passes the d-axis current Id to the stator coil within a phase angle range in which the combined torque ?T become larger than the field torque Tf in order to generate the reluctance torque Tr which is equal to (Ld?Lq)Id·Iq in addition to the field torque Tf.

Abstract: The Lundell motor apparatus includes a controller for controlling a field current passed to a field coil of a Lundell-type rotor of a motor and an armature current passed to a stator coil of the motor in order to generate a required torque. When the field current is If, the armature current is Ia, a d-axis inductance is Ld, a q-axis inductance is Lq, a q-axis current as a q-axis component of the armature current is Iq, a d-axis current as a d-axis component of the armature current is Id, a field torque is Tf, a field flux is ?f, a reluctance torque is Tr, and a combined torque of the field torque and the reluctance torque is ?T, the controller passes the d-axis current Id to the stator coil within a phase angle range in which the combined torque ?T become larger than the field torque Tf in order to generate the reluctance torque Tr which is equal to (Ld?Lq)Id·Iq in addition to the field torque Tf.

Abstract: A brush holder in a tandem vehicle alternator for a vehicle is composed mainly of a primary brush holder and a secondary brush holder accommodating plural brushes, respectively. The primary and secondary brush holders are independently formed. During a step of producing a brush assembly and of mounting the brush assembly on the tandem vehicle alternator, both of the primary and secondary brush holders are integrated into a single brush holder and tightly fastened by welding using a connection metal member.

Abstract: A stator coil includes a belt-shaped winding band and a same-layer bridging portion. The winding band makes one or more rounds, while turning back in the axial direction a plurality of conductor wires which are aligned in parallel at a pitch of electric angle ? (pi). The same-layer bridging portion connects a pair of the conductor wires which are of the same phase at the end portion of the winding and which are arranged in the same layer of the slot. Such arrangement enables forming a compact multi-phase stator coil.

Abstract: In a reluctance rotary electric machine, a movable part is arranged opposing part of an alignment of a plurality of stator poles to be movable in a predetermined direction. In the movable part, at least one pair of salient poles is configured to magnetically couple to the excited at least one first pair of the plurality of poles so as to form a first magnetic flux in loop thereamong. A segment magnetic-path portion is arranged to be magnetically separated from the at least one pair of salient poles. The segment magnetic-path portion works to magnetically couple therethrough between the at least one second pair of the plurality of stator poles so as to form a second magnetic flux in loop thereamong. The first magnetic flux and second magnetic flux create a reluctance force to move the movable part in the predetermined direction.

Abstract: According to the present invention, an alternator includes a rotor, a stator, and at least one cooling fan. The rotor includes a rotary shaft, a field core, and a field coil. The field coil has first and second ends that are opposite to each other in an axial direction of the rotary shaft. The stator includes an armature core and an armature coil. The armature core has first and second ends that are opposite to each other in the axial direction. The first end of the armature core is closer to the first end than the second end of the field coil. An axial distance between the first and second ends of the field coil is less than that between the first and second ends of the armature core. The first end of the field coil protrudes outward from the first end of the armature core in the axial direction.

Abstract: According to the invention, a tandem alternator includes a rotary shaft, a first and a second power generation unit that are arranged in tandem in the axial direction of the rotary shaft, a housing, a slip ring-brush mechanism provided around a rear end portion of the rotary shaft, and a first and a second rectifier that are respectively fixed to a front and a rear end face of the housing, and a controller. The controller is electrically connected between the first rectifier and the slip ring-brush mechanism to control, at least, supply of the first field current to the first field winding. The controller is configured to form a freewheeling circuit when the first field current is interrupted. The controller is fixed to the rear end face of the housing to minimize the distance from the controller to the slip ring-brush mechanism, thereby minimizing resistance loss of the freewheeling circuit.

Abstract: A rotor of a synchronous motor includes a rotating shaft, a plurality of segments, a plurality of permanent magnets, and a field coil. The segments are located radially outward of the rotating shaft and arranged in the circumferential direction of the rotating shaft at a predetermined pitch with spaces formed therebetween. Each of the segments has a recess making up a magnetic reluctance portion and an opposite pair of ends making up salient-pole portions. Each of the permanent magnets is disposed in one the spaces between the segments with a predetermined orientation of its N and S poles. The field coil is wound around the segments to extend in the circumferential direction of the rotating shaft through the recesses of the segments. The field coil creates, when energized with DC current, magnetic flux which magnetizes the pair of ends of each of the segments in opposite directions.

Abstract: According to the invention, a tandem alternator includes a rotary shaft, a first and a second field arranged in tandem on the rotary shaft, and a first and a second armature arranged in tandem in the axial direction of the rotary shaft. The first armature is provided on an outer periphery of the first field to constitute a first power generation unit. The second armature is provided on an outer periphery of the second field to constitute a second power generation unit. The first and second fields are arranged to abut each other in the axial direction of the rotary shaft, so as to minimize the axial length of the alternator. The first and second fields are configured to respectively create a first and a second magnetomotive force whose directions are opposite to each other, so as to minimize magnetic leakage between the first and second power generation units.

Abstract: A vehicular electric rotary machine of a heat pipe cooling type is disclosed including heat pipe means 14, 14A, 15, 15B, associated with a cooling fin 51, 52 and a rear end wall 122 of a rear frame 12, which have regions exposed to an exhaust passage 19 to be cooled by a cooling wind Wa for thereby radiating heat of a rectifier.

Abstract: The Lundell motor apparatus includes a controller for controlling a field current passed to a field coil of a Lundell-type rotor of a motor and an armature current passed to a stator coil of the motor in order to generate a required torque. When the field current is If, the armature current is Ia, a d-axis inductance is Ld, a q-axis inductance is Lq, a q-axis current as a q-axis component of the armature current is Iq, a d-axis current as a d-axis component of the armature current is Id, a field torque is Tf, a field flux is ?f, a reluctance torque is Tr, and a combined torque of the field torque and the reluctance torque is ?T, the controller passes the d-axis current Id to the stator coil within a phase angle range in which the combined torque ?T become larger than the field torque Tf in order to generate the reluctance torque Tr which is equal to (Ld?Lq)Id·Iq in addition to the field torque Tf.

Abstract: In a synchronous reluctance motor composed of a stator core and a rotor core, convex grooves are formed along q-axis in an outer circumferential surface of the rotor core. A rotor coil is wound in the convex grooves. Applying a direct current to the rotor coil generates a torque of a current magnetic flux ?i in addition to a reluctance torque. Each convex groove formed at the q-axis prevents decreasing the reluctance torque. The rotor coil has a cross sectional shape in a diametrical direction of the rotor coil so that the rotor coil has a maximum diametrical width at the q-axis position, and the diametrical width of the rotor coil is gradually decreased according to the distance from the q-axis position.

Abstract: In a tandem AC generator for a vehicle having dual armature core-Lundel type field core pairs placed in series, an intermediate ring as a cylindrical spacer is placed between the dual armature cores. One armature core, the intermediate ring, and the other armature core are pressed and tightly fastened to each other in the direction of a rotary shaft by front and rear housings by a through bolt. A circumference wall part of the front housing accommodates one armature core and the intermediate ring completely and further accommodates a part of an outer circumference surface of the other armature core. This simple construction of the tandem AC generator provides improved and superior vibration proof.

Abstract: According to the invention, a tandem alternator includes a rotary shaft, a first and a second power generation unit arranged in tandem in the axial direction of the rotary shaft, a housing accommodating the power generation units and having a plurality of air holes formed through a front end wall thereof, a pulley provided on a front end portion of the rotary shaft which protrudes outside from the first end wall of the housing, and a first and a second rectifier working to respectively rectify AC powers output from the first and second power generation units. The first rectifier is so fixed to the outer surface of the front end wall of the housing as to be located on the radially outside of the pulley and cover only part of the air holes. The second rectifier is fixed to the outer surface of a rear end wall of the housing.

Abstract: The vehicle-use tandem electric rotating machine includes a first stator-rotor pair, a second stator-rotor pair, and a controller individually controlling a first field current flowing into a first field coil of the first stator-rotor pair and a second field current flowing into a second field coil of the second stator-rotor pair. The first stator-rotor pair is configured to generate electric power to be supplied to essential electric loads, and the second stator-rotor pair is configured to generate electric power to be supplied to non-essential electric loads. The controller is configured to restrict the second field current from flowing into the second field coil when rotational speed of a vehicle engine driving the tandem electric rotating machine is lower than a predetermined threshold speed set above an idle speed of the vehicle engine.

Abstract: According to the invention, there is provided a rotor for a rotating electrical machine which includes a rotary shaft, a pair of first and second pole cores fixed on the rotary shaft, a plurality of permanent magnets, and a magnet holder holding the permanent magnets. The magnet holder is made of a non-magnetic metal and has a plurality of holding portions and a plurality of connecting portions. Each of the holding portions is interposed between circumferentially adjacent two of claws of the first and second pole cores, so as to hold a corresponding one of the permanent magnets between the adjacent two claws. Each of the connecting portions circumferentially extends, through the radially inner side of a distal end portion of one of the claws of the first and second pole cores, to connect end portions of adjacent two of the holding portions which circumferentially bracket the distal end portion.

Abstract: In a SPM synchronous motor has a rotor and a stator, a permanent magnet is divided to magnet parts magnetized in a diameter direction of the rotor and serve as rotor magnetic poles. The rotor magnetic poles are alternately arranged along a circumferential direction of the rotor. The rotor core has a plurality of salient poles made of soft magnetic material. Each salient pole projects from the circumferential surface of the rotor core toward a gap between the rotor and the stator, and is placed at a central part of the corresponding magnet part in the circumferential direction. This structure increases a magnitude of a d-axis inductance Ld and enhances the effects obtained by performing a weakening magnetic flux control using a negative d-axis current Id during a high speed rotation of the motor within a power source voltage limiting range.