JP2000083350A - Alternating-current generator for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the cooling capability of a centrifugal fan and suppress temperature rise in a stator by forming a plurality of fan blades on the rim of a fan plate in the circumferential direction, and forming cooling air turbulent flow inducing means on the positive pressure planes of the fan blades. SOLUTION: Cooling air which flows along the positive pressure planes of fan blades 41 is forcedly separated from the boundaries of the positive pressure planes of the fan blades 41 by projections 43. As a result, the flow of cooling air is accelerated and jetted from the ends of the fan blades 41 on the blow-off side outward in the radial direction. Thus, induced turbulent flow of cooling air collides with and cools a stator coil and is thereafter exhausted from an emission port. Since in this way, the plurality of the projections 43 are formed on the central portions of the positive pressure planes of the fan blades 41, turbulence is produced in the cooling air passed on the fan blades 41. As a result, turbulent flows of the cooling air which collides with the stator coil is accelerated, and efficiency of cooling the stator coil is improved, and temperature rise in the stator 8 is suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicular alternator having a rundle-type rotor attached to an engine of a vehicle, and more particularly to a centrifugal fan structure of a vehicular alternator having improved cooling performance. .

[0002]

2. Description of the Related Art FIG. 13 is a sectional view showing the structure of a conventional vehicle alternator, and FIG. 14 is a perspective view showing a centrifugal fan of the vehicle alternator shown in FIG. In the conventional vehicle alternator, a rundle-type rotor 7 is rotatably mounted via a shaft 6 in a case 3 composed of an aluminum front bracket 1 and a rear bracket 2, and a stator 8 rotates. It is configured to be fixed to the inner wall surface of the case 3 so as to cover the outer peripheral side of the child 7. Shaft 6
Are rotatably supported by the front bracket 1 and the rear bracket 2. A pulley 4 is fixed to one end of the shaft 6 so that the rotational torque of the engine can be transmitted to the shaft 6 via a belt (not shown). A slip ring 9 for supplying an electric current to the rotor 7 is fixed to the other end of the shaft 6, and a pair of brushes 10 are housed in a brush holder 11 arranged in the case 3 so as to be in sliding contact with the slip ring 9. ing. A regulator 17 for adjusting the magnitude of the AC voltage generated by the stator 8 is bonded to the heat sink 16 fitted to the brush holder 11. A rectifier 12 that is electrically connected to the stator 8 and rectifies an alternating current generated in the stator 8 into a direct current is mounted in the case 3.

[0003] The rotor 7 is provided with a rotor coil 13 for generating a magnetic flux by passing a current, and a pair of magnetic poles formed by the magnetic flux generated by the rotor coil 13. And pole cores 18 and 19. The pair of pole cores 18 and 19 are made of iron,
A plurality of claw-shaped claw-shaped magnetic poles 20 and 21 are provided on the outer peripheral edge in a circumferential direction at an equiangular pitch, and are fixed to the shaft 6 so as to face each other so as to engage the claw-shaped magnetic poles 20 and 21. Adjacent claw-shaped magnetic poles 20 and 21 are provided with a certain gap 22 between the magnetic poles so as to prevent magnetic flux from leaking between the claws and to form a cooling air passage for cooling the rotor coil 13. Have been. The stator 8 includes the stator core 1
5 and a stator coil 16 in which a conductor is wound around the stator core 15 and an alternating current is generated by a change in magnetic flux from the rotor 7 as the rotor 7 rotates.

The centrifugal fan 5 has a plurality of polyamide fan blades 5a circumferentially attached to an outer peripheral portion of an iron fan plate 5b, and is fixed to both ends of the rotor 7 in the axial direction. The fan blade 5a has a smooth R-shaped outer surface.

In the conventional vehicular alternator configured as described above, the current is supplied from the battery (not shown) to the brush 10.
Then, the magnetic flux is supplied to the rotor coil 13 via the slip ring 9 to generate a magnetic flux. By this magnetic flux, the claw-shaped magnetic pole 20 of one pole core 18 is magnetized to the N pole, and the claw-shaped magnetic pole 21 of the other pole core 19 is magnetized to the S pole. On the other hand, the rotational torque of the engine is transmitted to the shaft 6 via the belt and the pulley 4, and the rotor 7 is rotated. Then, a rotating magnetic field is applied to the stator coil 16, and an electromotive force is generated in the stator coil 16. The AC electromotive force is rectified to DC through the rectifier 12, and the magnitude thereof is adjusted by the regulator 17 to charge the battery.

[0006] Here, the centrifugal fan 5 rotates with the rotation of the rotor 7, and as shown by arrows in FIG. 13, cooling air flows from the inlets 1 a and 2 a of the front bracket 1 and the rear bracket 2, and is discharged. It is discharged from outlets 1b and 2b. That is, the cooling air flows in the direction of the shaft 6 and is discharged radially outward. Therefore, the cooling air collides with the stator coil 16 and the temperature rise of the stator 8 that constantly generates heat during power generation is suppressed.

[0007]

In the conventional alternator for a vehicle configured as described above, the fan blades 5a of the centrifugal fan 5 are formed in a smooth R-shaped outer surface. The cooling air sucked in from the suction side end flows along the smooth outer surface of the fan blade 5a, and is blown radially outward from the blowing side end. Then, the cooling air blown out from the blowing-side end of the fan blade 5a collides with the stator coil 16 and cools it. However, since the cooling air is not sufficiently disturbed, excellent cooling performance cannot be obtained. was there.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. The fan blades of a centrifugal fan promote cooling air turbulence, improve the cooling performance of the centrifugal fan, and increase the temperature of the stator. It is an object of the present invention to obtain a vehicular AC generator capable of suppressing the occurrence of a vehicle.

[0009]

According to the present invention, there is provided a vehicle alternator having a pair of shafts rotatably supported by a case and a plurality of trapezoidal claw-shaped magnetic poles protruding from an outer peripheral edge. And a rotor disposed in the case and fixed to the shaft such that the pole cores are opposed to each other such that the claw-shaped magnetic poles mesh with each other, and fixed in the case so as to be located on the outer periphery of the rotor. In a vehicle AC generator including a stator having a stator core and a stator coil, and centrifugal fans fixed to both ends of the rotor in the axial direction, the centrifugal fan is disposed in the axial direction of the rotor. A fan plate disposed along both ends of the fan plate, and a plurality of fan blades disposed in a circumferential direction on an outer peripheral edge of the fan plate. Provided Is shall.

Further, the cooling air turbulence promoting means is provided on an outer diameter side of a positive pressure surface of the fan blade.

[0011] The cooling air turbulence promoting means is configured such that a plurality of protrusions are provided in an island shape on the positive pressure surface of the fan blade.

Further, the cooling air turbulence promoting means is configured such that a projection extends from one end in the axial direction of the pressure surface to the other end on the pressure surface of the fan blade. .

Further, the fan blade is mounted on the fan plate so as to be rotatable about an axis parallel to the axis, and is mounted such that the radial angle of the fan blade becomes large when the rotor rotates at a high speed. Things.

Further, the fan blade is formed by bending an outer peripheral portion of the fan plate by press forming, and the cooling air turbulence promoting means is provided on one end of the positive pressure surface of the fan blade in the axial center direction. From the other end to the other end.

Further, a ring-shaped plate is provided so as to cover an end surface of the fan blade provided on an outer peripheral edge portion of the fan plate in a circumferential direction on a side opposite to the fan plate.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. Embodiment 1 FIG. FIG. 1 is a perspective view showing a centrifugal fan applied to an automotive alternator according to Embodiment 1 of the present invention,
2 and 3 are a perspective view and a plan view, respectively, showing the fan blades of the centrifugal fan shown in FIG. In each figure, the fan blade 41 is made of polyimide, is formed in a smooth R-shaped outer surface shape, and has a small hemispherical projection 43 as a cooling air turbulence promoting means having an island at the center of one outer surface. A plurality are provided in a shape. Then, a plurality of fan blades 41 are provided on the outer peripheral portion of the iron fan plate 42 at an equal pitch in the circumferential direction or at an uneven pitch so that the outer surface on which the protrusion 43 is provided is a front surface in the rotational direction, that is, a positive pressure surface. The centrifugal fan 40 is attached and configured. The first embodiment is configured similarly to the vehicle alternator shown in FIG. 13 except that a centrifugal fan 40 is used instead of the conventional centrifugal fan 5 shown in FIG. I have.

Here, the flow of the cooling air generated by the centrifugal fan 40 rotating integrally with the rotor 7 will be described with reference to FIG. The rotation of the centrifugal fan 40 on the front side causes the case 3 to move from the inlet 1 a of the front bracket 1 to the case 3.
The cooling air that has flowed into the inside reaches the front-side centrifugal fan 40, and the fan plate 4
It is turned radially outward along 2 and enters the suction side end of the fan blade 41. Then, the cooling air flowing along the pressure surface of the fan blade 41 is forcibly separated from the interface of the pressure surface of the fan blade 41 by the projection 43. As a result, the turbulence of the cooling air is promoted, and the cooling air is blown radially outward from the blowing end of the fan blade 41. The turbulence-promoted cooling wind collides with the stator coil 16 and cools the stator coil 16.
It is discharged from the discharge port 1b. A part of the cooling air on the front side goes straight in the axial direction of the shaft 6, and enters the gap 22 between the magnetic poles through the space between the adjacent claw-shaped magnetic poles 21 of the pole core 19 on the front side. The cooling air that has entered the gap 22 between the magnetic poles cools the rotor coil 13 and the pole cores 18 and 19 to which the heat of the rotor coil 13 is transmitted, and then joins with the cooling air sucked from the rear side.

On the other hand, the cooling air flowing into the case 3 from the suction port 2a of the rear bracket 2 due to the rotation of the centrifugal fan 40 on the rear side cools heat-generating components such as the regulator 17, the rectifier 12, the brush 10, the slip ring 9, and the like. I do. Thereafter, the cooling air reaches the rear-side centrifugal fan 40, and is turned radially outward along the fan plate 42 by the action of the centrifugal fan 40, so that the fan blade 41
Into the suction side end of Then, the cooling air flowing along the pressure surface of the fan blade 41 is forcibly separated from the interface of the pressure surface of the fan blade 41 by the projection 43. As a result, the turbulence of the cooling air is promoted, and the cooling air is blown radially outward from the blowing end of the fan blade 41. The turbulence-promoted cooling air flows into the stator coil 16.
After cooling the stator coil 16, the discharge port 2 b
Is discharged from Part of the cooling air on the rear side goes straight in the axial direction of the shaft 6, and enters the gap 22 between the magnetic poles passing between the adjacent claw-shaped magnetic poles 20 of the pole core 18 on the rear side. The cooling air that has entered the gap 22 between the magnetic poles is applied to the rotor coil 13 and the pole core 1 to which the heat of the rotor coil 13 is transmitted.
After cooling 8 and 19, it joins with the cooling air sucked in from the front side.

According to the first embodiment, since the plurality of projections 43 are provided at the center of the positive pressure surface of the fan blade 41, the cooling air passing through the fan blade 41 can be disturbed. . Therefore, the stator coil 1
6 is turbulently accelerated, and the stator coils 16
Can be improved, and the temperature rise of the stator 8 can be suppressed. In the first embodiment, the cooling air turbulence promoting means is formed by providing a large number of protrusions 43 on the positive pressure surface of the fan blade 41 in an island shape. Similar effects can be obtained by providing a large number of concave portions or a large number of minute irregularities on the positive pressure surface of the fan blade 41 to constitute the cooling air turbulence promoting means.

Embodiment 2 In the second embodiment, as shown in FIGS. 4 and 5, a plurality of projections 43 are provided in an island shape on the outer diameter side of the pressure surface of the fan blade 41a. According to the second embodiment, since the protrusion 43 is provided on the outer diameter side of the positive pressure surface of the fan blade 41a having a high cooling air velocity, the cooling passing through the fan blade 41a is different from that of the first embodiment. The disturbance caused by the wind can be promoted. Thus, the cooling performance of the stator 8 can be further improved.

Embodiment 3 In the third embodiment, as shown in FIGS. 6 and 7, a projection 44 having a semicircular cross section as a cooling air turbulence promoting means is provided on the outer diameter side of one outer surface (positive pressure surface) of the fan blade 41b. The shaft 6 extends from one end of the shaft 6 in the axial direction to the other end thereof in parallel with the axial direction of the shaft 6. In the third embodiment, the protrusion 44 is provided on the outer diameter side of the pressure surface of the fan blade 41b from one end in the axial direction of the shaft 6 to the other end. The flow of the cooling air flowing along the positive pressure surface is blocked in the entire area of the shaft 6 in the axial direction. Therefore, according to the third embodiment, the turbulence in the cooling air passing through the fan blade 41b can be reliably generated as compared with the first and second embodiments, and the cooling performance of the stator 8 is further improved. Can be done.

Embodiment 4 In the fourth embodiment, as shown in FIG. 8, a plurality of fan blades 41b are mounted on the outer peripheral portion of the fan plate 42 at a constant pitch or at a variable pitch in the circumferential direction. The centrifugal fan 40a is configured so as to sandwich a plurality of fan blades 41b arranged in the circumferential direction in opposition to the fan plate 42 and to sandwich the fan blades 41b.

In the fourth embodiment, the fan blade 4
The cooling air that has entered from the suction side end of the fan blade 41b flows along the pressure surface of the fan blade 41b, and is forcibly separated from the interface of the pressure surface of the fan blade 41b by the protrusion 44.
The turbulence is promoted, and the air is blown radially outward from the blow-side end of the fan blade 41b. Since the cooling air passage surrounded by the fan blade 41b, the fan plate 42, and the plate 45 is formed, the cooling air that has entered from the suction side end of the fan blade 41b is blown out in a direction other than the radial direction. Is suppressed. Therefore, according to the fourth embodiment, the cooling air that has entered from the suction side end of the fan blade 41b is blown radially outward from the blowing side end of the fan blade 41b without any leakage. The amount of cooling air supplied for cooling increases, and the turbulence of the cooling air by the projections 44 increases, so that the cooling performance can be further improved.

Embodiment 5 FIG. 9 is a partially broken plan view showing a centrifugal fan applied to the automotive alternator according to Embodiment 5 of the present invention, and FIG. 10 is a partially broken enlarged view showing a main part of the centrifugal fan shown in FIG. FIG. 11 is a plan view, and FIG. 11 is a sectional view taken along the line XI-XI in FIG. In each of the figures, a plurality of fan blades 41c are attached to the outer peripheral portion of the fan plate 42 at a constant pitch in the circumferential direction or at a variable pitch. The protrusion 44 is provided on the outer diameter side of the pressure surface of the fan blade 41c so as to extend from one end of the shaft 6 in the axial direction to the other end. In addition, the ring-shaped plate 45
Are mounted so as to sandwich a plurality of fan blades 41 b arranged in the circumferential direction in opposition to the fan plate 42. The fan blade 41c is rotatably mounted between the fan plate 42 and the plate 45 about an axis 46 parallel to the axial direction of the shaft 6.
Further, the fan blade 41c is urged in the rotation direction of the shaft 6 around the axis 46 by a coil spring 47 as an elastic member.

In the centrifugal fan 40b configured as described above, a rotational moment in the direction opposite to the rotational direction of the rotor 7 is generated around the shaft 46 with the rotation of the rotor 7 by the fan blade 41.
Acts on c. This rotational moment causes the fan blade 41c to move the shaft 46 against the urging force of the coil spring 47.
The rotor 7 is turned around in a direction opposite to the rotation direction of the rotor 7. Therefore, the radial angle θ of the fan blade 41c shown in FIG. 9 is changed according to the rotation speed of the rotor 7. That is,
As the rotation speed of the rotor 7 increases, the fan blade 4
The radial angle θ of 1c increases.

In the region where the rotation speed of the rotor 7 is low, the radial angle θ of the fan blade 41c is small. Therefore, the cooling air that has entered from the suction side end of the fan blade 41c flows along the pressure surface of the fan blade 41c, and is forcibly separated from the interface of the pressure surface of the fan blade 41c by the projections 44, and turbulence is promoted. The fan blade 41c is blown radially outward from a blow-side end of the fan blade 41c, and is used for cooling the stator coil 16. When the rotation speed of the rotor 7 increases, the radial angle θ of the fan blade 41c gradually increases. When the radial angle θ of the fan blade 41c exceeds a predetermined value, the cooling air that has entered from the suction side end of the fan blade 41c flows along the positive pressure surface of the fan blade 41c, and flows in the radial middle of the positive pressure surface. The separation and turbulence are promoted from the interface of the positive pressure surface, and the air is blown radially outward from the blow-out end of the fan blade 41 c to be used for cooling the stator coil 16. At this time, the projections 44 are not involved in promoting the turbulence of the cooling air.

In each of the above embodiments, the higher the rotation speed of the rotor 7, the more the turbulence of the cooling air by the projections 43 and 44 is promoted, and the cooling performance is improved. Causes the wind noise generated when the wind noise is generated. However, in the fifth embodiment, in the high-speed rotation range, the radial angle θ of the fan blade 41c increases, and the protrusion 44 does not contribute to the promotion of the turbulence of the cooling air. Therefore, according to the fifth embodiment, the cooling performance can be improved without deteriorating the wind noise. In the fifth embodiment, the coil spring 47 is used as the elastic member. However, the elastic member is not limited to the coil spring 47, and for example, a plate spring may be used.

Embodiment 6 FIG. FIG. 12 is a perspective view showing a centrifugal fan applied to the automotive alternator according to Embodiment 6 of the present invention. In FIG. 12, the fan blade 48 is formed by bending an outer peripheral edge of an iron fan plate 49 at a plurality of positions at equal pitches or unequal pitches by press working. The groove 50 as the cooling air turbulence promoting means is parallel to the axial direction of the shaft 6 such that the groove 50 extends from one axial end of the shaft 6 to the other radial end of the positive pressure surface of the fan blade 48. Is recessed.
Further, the ring-shaped plate 45 is
The fan blades 48 are arranged so as to sandwich a plurality of fan blades 48 arranged in the circumferential direction in opposition to the fan blades 48.

In the centrifugal fan 40c configured as described above, the cooling air that has entered from the suction side end of the fan blade 48 flows along the positive pressure surface of the fan blade 48,
The concave portion 50 forcibly separates and promotes turbulence from the interface of the positive pressure surface of the fan blade 48, and is blown radially outward from the blowout side end of the fan blade 48 to be used for cooling the stator coil 16. In addition, fan blade 4
8. Since the cooling air passage surrounded by the fan plate 49 and the plate 45 is formed, the cooling air that has entered from the suction side end of the fan blade 48 is prevented from being blown out in a direction other than the radial direction. You. Therefore,
In the sixth embodiment, the same effect as in the fourth embodiment can be obtained.

Here, when the fan blade is formed by bending and raising the outer peripheral edge of the fan plate by press working, the positive pressure surface of the fan blade is pressed and bent. No protrusion can be formed on the surface. Also, it is extremely difficult to form a projection on the positive pressure surface of the fan blade after pressing. However, in the sixth embodiment, since the concave groove 50 is formed on the pressure surface of the fan blade 48, for example, in the step of punching the fan plate 49 from the plate material, the concave groove 50 is formed at a portion corresponding to the pressure surface of the fan blade. 50 engraved and punched fan plate 49
The fan blade 48 can be formed by bending and raising the outer peripheral edge portion by press working. At this time, since the projection formed when the concave groove 50 is carved is formed at a portion corresponding to the negative pressure surface of the fan blade, the bending caused by the press working is performed without any problem.

As described above, according to the sixth embodiment,
Since the fan blade 48 integrally formed with the fan plate 49 can be easily formed from a plate material by press working, there is no need to configure the fan plate and the fan blade as separate parts as in the above-described embodiments. And the cost is reduced.

[0032]

Since the present invention is configured as described above, it has the following effects.

According to the present invention, the shaft rotatably supported by the case and the pair of pole cores having a plurality of trapezoidal claw-shaped magnetic poles protruding from the outer peripheral edge engage the claw-shaped magnetic poles with each other. A rotor fixed to the shaft and disposed in the case so as to face the stator, and a stator having a stator core and a stator coil disposed in the case so as to be located on the outer periphery of the rotor. A centrifugal fan fixed to both ends in the axial direction of the rotor, wherein the centrifugal fan is a fan plate disposed along both ends in the axial direction of the rotor. And a plurality of fan blades arranged in the circumferential direction at the outer peripheral edge of the fan plate, and the cooling air turbulence promoting means is provided on the positive pressure surface of the fan blade. Offered Cooling air is promoted turbulence is enhanced cooling performance of the centrifugal fan, it is possible to obtain a vehicle AC generator capable of suppressing temperature increases in the stator.

Further, since the cooling air turbulence promoting means is provided on the outer diameter side of the positive pressure surface of the fan blade,
Turbulence of the cooling air is promoted, and the cooling performance can be further improved.

Further, since the cooling air turbulence promoting means has a plurality of projections provided on the positive pressure surface of the fan blade in an island shape, the cooling air turbulence promoting means can be easily constituted. .

In addition, the cooling air turbulence promoting means is configured such that the projection extends from one end of the positive pressure surface in the axial direction to the other end of the positive pressure surface of the fan blade. The turbulence of the cooling air is promoted in the entire axial direction of the pressure surface, and the cooling performance can be improved accordingly.

Further, the fan blade is mounted on the fan plate so as to be rotatable about an axis parallel to the axis, and is mounted such that the radial angle of the fan blade increases when the rotor rotates at a high speed. Therefore, the fan blades rotate around the axis in the high-speed rotation range of the centrifugal fan, and the cooling wind turbulence promoting means prevents the cooling wind from promoting the turbulent flow, thereby reducing the temperature rise of the stator without deteriorating the wind noise. Can be suppressed.

The fan blade is formed by bending the outer peripheral edge of the fan plate by press molding, and the cooling air turbulence promoting means is provided on one end of the positive pressure surface of the fan blade in the axial direction. The groove is formed from the groove to the other end, so that the fan blade integrally formed on the fan plate can be easily manufactured from the plate material by pressing, improving the productivity and reducing the cost. Is achieved.

Further, since the ring-shaped plate is disposed so as to cover the end face of the fan blade provided on the outer peripheral edge of the fan plate in the circumferential direction on the side opposite to the fan plate, the fan blade The cooling air that has entered from the suction side end is blown out from the blowing side end without leakage, so that turbulence is promoted and cooling performance can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a centrifugal fan applied to an automotive alternator according to Embodiment 1 of the present invention.

FIG. 2 is a perspective view showing a fan blade of the centrifugal fan applied to the automotive alternator according to Embodiment 1 of the present invention;

FIG. 3 is a plan view showing a fan blade of the centrifugal fan applied to the automotive alternator according to Embodiment 1 of the present invention;

FIG. 4 is a perspective view showing a fan blade of a centrifugal fan applied to an automotive alternator according to Embodiment 2 of the present invention.

FIG. 5 is a plan view showing a fan blade of a centrifugal fan applied to the automotive alternator according to Embodiment 2 of the present invention.

FIG. 6 is a perspective view showing a fan blade of a centrifugal fan applied to an automotive alternator according to Embodiment 3 of the present invention.

FIG. 7 is a plan view showing a fan blade of a centrifugal fan applied to a vehicle alternator according to Embodiment 3 of the present invention.

FIG. 8 is a perspective view showing a centrifugal fan applied to an automotive alternator according to Embodiment 4 of the present invention.

FIG. 9 is a partially broken plan view showing a centrifugal fan applied to an automotive alternator according to Embodiment 5 of the present invention.

FIG. 10 is a partially broken enlarged plan view showing a main part of a centrifugal fan applied to an automotive alternator according to Embodiment 5 of the present invention.

11 is a sectional view taken along the line XI-XI in FIG.

FIG. 12 is a partially broken perspective view showing a centrifugal fan applied to an automotive alternator according to Embodiment 6 of the present invention.

FIG. 13 is a sectional view showing a conventional vehicle alternator.

FIG. 14 is a perspective view showing a centrifugal fan applied to a conventional vehicle alternator.

[Explanation of symbols]

3 cases, 6 shafts, 7 rotors, 8 stators,
15 Stator core, 16 Stator coil, 18, 19
Pole core, 20, 21 Claw-shaped magnetic pole, 40, 40a, 4
0b, 40c Centrifugal fan, 41, 41a, 41b, 4
1c, 48 fan blades, 42, 49 fan plates, 43, 44 protrusions (cooling air turbulence promoting means), 45
Plate, 46 axes, 47 Coil spring (elastic member), 50 concave groove (cooling air turbulence promoting means).

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference)

Claims (7)

[Claims] A shaft rotatably supported by a case and a pair of pole cores having a plurality of trapezoidal claw-shaped magnetic poles protruding from an outer peripheral edge thereof are opposed to each other so as to mesh with each other. A rotor fixed to the shaft and disposed in the case, a stator having a stator core and a stator coil disposed in the case so as to be located on the outer periphery of the rotor, and the rotor A centrifugal fan fixed to both ends of the rotor in the axial direction, wherein the centrifugal fan includes a fan plate disposed along both axial ends of the rotor; An alternator for a vehicle, comprising: a plurality of fan blades arranged in a circumferential direction on an outer peripheral portion of a plate; and cooling air turbulence promoting means provided on a positive pressure surface of the fan blade. 2. The vehicle alternator according to claim 1, wherein said cooling wind turbulence promoting means is provided on an outer diameter side of a pressure surface of said fan blade. 3. The vehicular vehicle according to claim 1, wherein the cooling air turbulence promoting means comprises a plurality of protrusions provided in an island shape on a pressure surface of the fan blade. Alternator. 4. The cooling wind turbulence promoting means is characterized in that a projection is provided on the pressure surface of the fan blade so as to extend from one end to the other end in the axial direction of the pressure surface. The vehicle alternator according to claim 1 or 2, wherein: 5. The fan blade is mounted on the fan plate so as to be rotatable around an axis parallel to the axis, and is mounted so that the radial angle of the fan blade increases when the rotor rotates at a high speed. The vehicle alternator according to any one of claims 1 to 4, characterized in that: 6. The fan blade is formed by bending an outer peripheral edge of the fan plate by press molding, and the cooling air turbulence promoting means is provided at one end of the positive pressure surface of the fan blade in the axial center direction. 2. The alternator for a vehicle according to claim 1, wherein the alternator is constituted by a concave groove formed so as to reach from the other end to the other end. 7. A ring-shaped plate is provided so as to cover an end surface of the fan blade provided on an outer peripheral edge of the fan plate in a circumferential direction on a side opposite to the fan plate. The vehicle alternator according to any one of claims 1 to 6.