Abstract: An alternating current generator for vehicles includes a stator, a rotor having a Lundell type core and a magnetic field winding, first and second cooling fans which are fixed to an axial end surface of the Lundell type core and generate cooling air along with the rotation of the rotor, and a fan base which is disposed between the second cooling fan and the Lundell type core and regulates the cooling air. The Lundell type core includes a plurality of U-shaped clearances formed in the outer periphery of the axial end surface being circumferentially spaced apart from each other. The fan base includes a plurality of alternately and circumferentially disposed large-diameter portions and small-diameter portions, with at least one of the small-diameter portions being disposed axially confronting a U-shaped clearance.

Abstract: An alternating current generator for vehicles includes a stator, a rotor having a Lundell type core and a magnetic field winding, first and second cooling fans which are fixed to an axial end surface of the Lundell type core and generate cooling air along with the rotation of the rotor, and a fan base which is disposed between the second cooling fan and the Lundell type core and regulates the cooling air. The Lundell type core includes a plurality of U-shaped clearances formed in the outer periphery of the axial end surface being circumferentially spaced apart from each other. The fan base includes a plurality of alternately and circumferentially disposed large-diameter portions and small-diameter portions, with at least one of the small-diameter portions being disposed axially confronting a U-shaped clearance.

Abstract: An alternator for a vehicle is provided which is equipped with a heat dissipator and a cooling air generator. The heat dissipator is disposed in a rectifier to cool rectifying devices. The cooling air generator generates a flow of cooling air to the heat dissipator. The heat dissipator has a plurality of sub-fins formed thereon. Each of the sub-fins is defined by a combination of a protrusion and a recess. The protrusions are formed on one of opposed major surfaces of the heat dissipator, while the recesses are formed on the other major surface, one in coincidence with each of the protrusions in a thickness-wise direction of the heat dissipator. This permits the heat dissipator to be pressed to form the protrusions and the recesses to make the sub-fins simultaneously, thus allowing a heat-dissipating area to be increased to ensure a desired degree of heat capacity thereof.

Abstract: An alternator has front and rear bearings, supported by front and rear frames, to rotatably support a shaft of a rotor extending along axial direction. A washer is located between the rear frame and the rear bearing to apply pressing force to the rear bearing slightly movable along axial direction. The washer has a ring-shaped base portion concentrically located with the rear bearing, slanting portions extending from the base portion toward outside of radial direction such that two adjacent slanting portions arranged as each pair along circumferential direction are inclined to different sides of axial direction, and flattened portions extending from respective slanting portions toward outside and being parallel to the base portion. Flattened portions shifted to front side are in contact with the rear bearing, and flattened portions shifted to rear side are in contact with the rear frame.

Abstract: An alternator for a vehicle is provided which is equipped with a heat dissipator and a cooling air generator. The heat dissipator is disposed in a rectifier to cool rectifying devices. The cooling air generator generates a flow of cooling air to the heat dissipator. The heat dissipator has a plurality of sub-fins formed thereon. Each of the sub-fins is defined by a combination of a protrusion and a recess. The protrusions are formed on one of opposed major surfaces of the heat dissipator, while the recesses are formed on the other major surface, one in coincidence with each of the protrusions in a thickness-wise direction of the heat dissipator. This permits the heat dissipator to be pressed to form the protrusions and the recesses to make the sub-fins simultaneously, thus allowing a heat-dissipating area to be increased to ensure a desired degree of heat capacity thereof.

Abstract: An alternator has front and rear bearings, supported by front and rear frames, to rotatably support a shaft of a rotor extending along axial direction. A washer is located between the rear frame and the rear bearing to apply pressing force to the rear bearing slightly movable along axial direction. The washer has a ring-shaped base portion concentrically located with the rear bearing, slanting portions extending from the base portion toward outside of radial direction such that two adjacent slanting portions arranged as each pair along circumferential direction are inclined to different sides of axial direction, and flattened portions extending from respective slanting portions toward outside and being parallel to the base portion. Flattened portions shifted to front side are in contact with the rear bearing, and flattened portions shifted to rear side are in contact with the rear frame.

Abstract: AC generator for vehicles is provided with a frame that supports a rotor and a stator, a rectifier that rectifies an output of the stator and has an output terminal, and a rear cover that covers electric parts including the rectifier. The rear cover is provided with a drain hole in the side part of the output terminal, and a wall part that adjoins the drain hole provided in the output terminal side.

Abstract: A brush assembly for an alternator includes a brush, a brush holder holing the brush, and a slip ring cover for covering a slip ring on a rotary shaft of the alternator. The brush holder and the slip ring cover respectively have first and second through-holes that can be brought into alignment with each other by application of a mechanical force. The alignment allows a retainer to be placed through both the first and second through-holes to retain the brush in the brush holder against the spring force of a spring, thereby permitting installation of the brush assembly onto the rotary shaft to be carried out without interference between the brush and the slip ring. The first and second through-holes are brought out of the alignment by removal of the mechanical force and the retainer, thereby blocking foreign matters from entering inside through both the first and second through-holes.

Abstract: A vehicle alternator is disclosed having a stator, a rotor, a frame surrounding the stator and the rotor, a bowl-shaped end cover mounted on the frame and defining an electric component-part compartment, a brush unit held in sliding contact with slip rings of a rotary shaft, and a rectifier unit. The rectifier unit includes a terminal block embedded with A.C. conductive segments for multi-phase windings of a stator coil. The end cover includes a base wall portion and protective partitioned compartments axially protruding from a base wall portion of the end cover toward the frame at circumferentially spaced positions for the multi-phase windings, respectively, for surrounding at least one circumference of a connecting portion between an exposed end portion of each A.C. conductive segment and a diode lead and a connecting portion between the exposed end portion of each A.C. conductive segment and a stator lead.

Abstract: The vehicle-use generator driven by a vehicle engine at a rotating shaft thereof includes a rotor rotatably mounted to the rotating shaft, a stator fixedly located radially outward of the rotor, a cooling fan fixed to the rotor to rotate together with the rotating shaft in order to generate cooling air for cooling the stator, and a housing that houses the rotor and the stator and rotatably supports the rotating shaft. The housing is provided with ribs arranged in a circumferential direction of the rotating shaft so as to form cooling air outlet windows. The ribs are inclined with respect to a radial direction of the rotating shaft, and shaped such that widths of the ribs are gradually changed cyclically in the circumferential direction.

Abstract: AC generator for vehicles is provided with a frame that supports a rotor and a stator, a rectifier that rectifies an output of the stator and has an output terminal, and a rear cover that covers electric parts including the rectifier. The rear cover is provided with a drain hole in the side part of the output terminal, and a wall part that adjoins the drain hole provided in the output terminal side.

Abstract: An automotive alternator has slip-rings connected to a rotor shaft and a brush device covering the slip-rings. The brush device is composed of a brush holder supporting brushes therein and a slip-ring cover firmly connected to the brush holder. The slip-ring cover includes a wall curved in a U-shape and a pair of flat walls closing the axial ends of the curved wall. Openings for ventilating the brushes and the slip-rings are formed between the curved wall of the slip-ring cover and the sidewalls of the brush holder. When the brushes are positioned downward of the slip-rings, the openings are open to the downward of the slip-rings. Therefore, water is prevented from entering into the brush device through the openings.

Abstract: A vehicle alternator for generating electric power has a stator, a rotor, a rectifier, a regulator case, and a cooling fin part. A stator winding is wound on the stator. The rotor is placed on opposite faces to the stator. The rectifier rectifies an alternating current output voltage excited in the stator winding. The regulator case accommodates a regulator substrate for adjusting the output voltage and a heat sink. On one surface of the heat sink the regulator substrate is mounted. The cooling fin part has plural cooling fins bonded to the other surface of the heat sink. The cooling fin part and the heat sink are made of a same material of a superior thermal expansion coefficient, such as copper or copper alloy.

Abstract: A vehicle alternator is disclosed having a stator, a rotor, a frame surrounding the stator and the rotor, a bowl-shaped end cover mounted on the frame and defining an electric component-part compartment, a brush unit held in sliding contact with slip rings of a rotary shaft, and a rectifier unit. The rectifier unit includes a terminal block embedded with A.C. conductive segments for multi-phase windings of a stator coil. The end cover includes a base wall portion and protective partitioned compartments axially protruding from a base wall portion of the end cover toward the frame at circumferentially spaced positions for the multi-phase windings, respectively, for surrounding at least one circumference of a connecting portion between an exposed end portion of each A.C. conductive segment and a diode lead and a connecting portion between the exposed end portion of each A.C. conductive segment and a stator lead.

Abstract: A brush assembly for an alternator includes a brush, a brush holder holing the brush, and a slip ring cover for covering a slip ring on a rotary shaft of the alternator. The brush holder and the slip ring cover respectively have first and second through-holes that can be brought into alignment with each other by application of a mechanical force. The alignment allows a retainer to be placed through both the first and second through-holes to retain the brush in the brush holder against the spring force of a spring, thereby permitting installation of the brush assembly onto the rotary shaft to be carried out without interference between the brush and the slip ring. The first and second through-holes are brought out of the alignment by removal of the mechanical force and the retainer, thereby blocking foreign matters from entering inside through both the first and second through-holes.

Abstract: A vehicle alternator for generating electric power has a stator, a rotor, a rectifier, a regulator case, and a cooling fin part. A stator winding is wound on the stator. The rotor is placed on opposite faces to the stator. The rectifier rectifies an alternating current output voltage excited in the stator winding. The regulator case accommodates a regulator substrate for adjusting the output voltage and a heat sink. On one surface of the heat sink the regulator substrate is mounted. The cooling fin part has plural cooling fins bonded to the other surface of the heat sink. The cooling fin part and the heat sink are made of a same material of a superior thermal expansion coefficient, such as copper or copper alloy.

Abstract: The vehicle-use generator driven by a vehicle engine at a rotating shaft thereof includes a rotor rotatably mounted to said rotating shaft, a stator fixedly located radially outwardly of the rotor, a cooling fan fixed to the rotor to rotate together with the rotating shaft in order to generate cooling air for cooling the stator, and a housing housing the rotor and the stator and rotatably supporting the rotating shaft. The housing is provided with a plurality of ribs arranged in a circumferential direction of the rotating shaft so as to form a plurality of cooling air outlet windows. The plurality of the ribs are inclined with respect to a radial direction of the rotating shaft, and shaped such that widths of the plurality of the ribs are gradually changed thereamong cyclically in the circumferential direction.

Abstract: An automotive alternator has slip-rings connected to a rotor shaft and a brush device covering the slip-rings. The brush device is composed of a brush holder supporting brushes therein and a slip-ring cover firmly connected to the brush holder. The slip-ring cover includes a wall curved in a U-shape and a pair of flat walls closing the axial ends of the curved wall. Openings for ventilating the brushes and the slip-rings are formed between the curved wall of the slip-ring cover and the sidewalls of the brush holder. When the brushes are positioned downward of the slip-rings, the openings are open to the downward of the slip-rings. Therefore, water is prevented from entering into the brush device through the openings.