JPH05111222A - Ac generator for vehicle - Google Patents

Abstract

(57) [Abstract] [Object] In the invention of claim 1, the wind noise by the fan is reduced, and further, the air volume is increased or prevented from being reduced. According to the second aspect of the invention, the side plate is fixed to the fan with high productivity. According to the invention of claim 1, a side plate is fixed to the end of the blade of the fan, the difference between the inner radius of the side plate and the inner radius of the intake hole of the bracket is made larger than the blade width, and the inner radius of the side plate is intaken. Make it smaller than the outside radius. According to the second aspect of the invention, the projection for welding is provided on either one of the end portion of the blade of the fan and the side plate to perform projection welding.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicular AC generator of a salient pole rotary type rotor supported by a bracket, and particularly to reducing wind noise of a fan attached to both ends of a magnetic pole iron core.

[0002]

5 and 6 are a longitudinal sectional view and a front view of a conventional vehicular AC generator. In the figure, 1 is a stator, which comprises a stator core 2 and a stator coil 3. 4 is a rotor, which is configured as follows. Reference numerals 5 and 6 are magnetic pole cores of opposite polarities, and both magnetic pole tooth portions 5a and 6a are alternately projected in the circumferential direction. 7 is an exciting coil held between the magnetic pole cores 5 and 6, 8 is a rotary shaft to which the magnetic pole cores 5 and 6 are fixed, 9 is a pair of slip rings fixed to the rotary shaft 8 via an insulating sleeve, 10 Reference numerals 11 and 11 denote fans fixed to the magnetic pole cores 5 and 6.

Next, 12 and 13 are front brackets and rear brackets, which connect the stator core 2 with tightening bolts 14. Due to ventilation, the front bracket 12 has a plurality of intake holes 12a at its end and a plurality of exhaust holes 12b at its outer periphery.
And are provided. Further, the rear bracket 13 is provided with a plurality of intake holes 13a at the end and a plurality of exhaust holes 13b at the outer peripheral part for ventilation. The rotating shaft 8 is a bearing 15
And 16 through front bracket 12 and rear bracket 1
It is supported by 3. Reference numeral 17 denotes a pulley fixed to the rotary shaft 8, and the rotation of the engine is transmitted via a belt to rotate the rotor 4.

A rectifier 18 rectifies the AC voltage induced in the stator coil 3 into a DC voltage and outputs the DC voltage, and a voltage adjuster 19 detects the rectifier output voltage and controls the exciting current to adjust the terminal voltage to a predetermined value. It is a vessel. 20 is a brush holder,
The held brush 21 is pressed against the slip ring 9 to pass an exciting current.

In the above AC generator, when the rotor 4 is rotated, an AC voltage is induced in the stator coil 3 to supply electric power and generate heat. The stator 1 part and the rotor 4 part are cooled by the ventilation generated by the rotation of the fans 10 and 11.

The cooling air generated by the rotation of the fan 10 is indicated by an arrow A.
As described above, the air is taken in through the air intake hole 12a of the front bracket 12, the stator 1 part is cooled, and is discharged through the air exhaust hole 12b.
The cooling air generated by the rotation of the fan 11 is sucked through the intake holes 13a of the rear bracket 13 as indicated by an arrow B, and the rectifier 1
8, the voltage regulator 19, the current collector unit, and the stator 1 unit are cooled and discharged from the exhaust hole 13b.

[0007]

In the conventional vehicle alternator as described above, the surfaces of the front bracket 12 and the rear bracket 13 that face the blades 10a of the fan 10 and the blades 11a of the fan 11 are uneven. However, there was a problem that the wind noise was high and the noise was loud.

The present invention has been made to solve the above problems, and an object thereof is to obtain a vehicle alternator in which wind noise of a fan is reduced.

[0009]

According to a first aspect of the present invention, in a vehicle alternator, a side plate is fixed to an end portion of a fan blade, and an inner radius of the side plate and an inner radius of an intake hole of a bracket. Is larger than the blade width, and the inner radius of the side plate is smaller than the outer radius of the intake hole.

According to the second aspect of the present invention, in order to fix the side plate to the axial end portion of the fan blade, a welding projection is provided at a required welding position on the end portion of the blade or the inner surface of the side plate, and the side plate is projection welded to the blade. It was done.

[0011]

In this invention, since the difference between the inner radius of the side plate and the inner radius of the intake hole of the bracket is larger than the width of the fan, a sufficient intake amount can be obtained from the intake hole. Is increased. Further, since the inner radius of the side plate is smaller than the outer radius of the intake hole, the smooth outer surface of the side plate corresponds to the unevenness due to the intake hole, so that noise is reduced.

According to the second aspect of the present invention, the side plate can be fixed to the blade of the fan by projection welding, and the productivity is improved.

[0013]

EXAMPLES Example 1. FIG. 1 is a longitudinal sectional view of an automotive alternator according to the present invention, which is 1-9, 12-21, 5a, 6
a, 12a, 12b, 13a and 13b are the same as those in FIG. Reference numeral 30 denotes a fan that is fixed to the end of the magnetic pole core 5 and has a side plate 31 fixed to the end of the blade 30a.
A fan 32 is fixed to the end of the magnetic pole core 6, and a side plate 33 is fixed to the end of the blade 32a.

FIGS. 2A and 2B are front views showing the front fan 30 and the rear fan 32. In FIG. 2A, a side plate 31 is fixed to the end of each bent blade 30a of the fan 30 by projection welding or the like. In FIG. 2B, the side plate 33 is fixed to the end of each bent blade 32a of the fan 32 by projection welding or the like. Reference numeral 32b is a reinforcing rib formed by pressing, and reference numeral 32c is a protruding portion for passing a connecting wire of the exciting coil 7 on the back surface side. Although the fan 30 is also provided with a reinforcing rib by pressing, it is not shown.

Returning to FIG. 1, the positional relationship between the front fan 30 and the intake holes 12a of the front bracket 12 is set as follows. r ₁ : intake hole inner radius, r ₂ : fan inner radius, r
R ₃ −r ₁ ≧ w, and r ₃ <r _{4 where 3} : inner radius of side plate, r ₄ : inner radius of intake hole, w: blade width.
It is set to _{r 1 <r 2 ≦ r 3} <r 4. In this way, the side plate 31
By making the difference between the inner radius and the inner radius of the intake hole 12a equal to the width of the blade 30a, the decrease in the air volume is eliminated, and by increasing it, the air volume is increased. This is because the intake from the intake holes 12a to the blades 30a becomes smooth and the intake amount increases. However, the outer radius of the intake hole 12a is made larger than the inner radius of the side plate 31. In this way, since the outer radius of the intake hole 12a is large, the intake amount increases and the air amount increases. Further, when r ₃ = r ₄ , the wind noise reduction effect is small. r
By setting ₃ <r ₄ , the order dispersion effect of the wind noise becomes large.

The stator core 2 has a diameter of 135 mm and 16 poles,
The number of blades of the front fan 30 is 11 and the rear of the side plate 31 is 8
In the case of a three-phase AC generator having 4 mm, the number of blades of the subsequent fan 32 is 13 and the inner diameter of the side plate 33 is 81 mm, the actual measurement result shows that the air volume is increased by 1.3 times as compared with the case without the side plate. Also,
Wind noise is about 3 dB at 12000 to 18000 r / min
Fell.

Embodiment 2. The side plate 31 is fixed to the end of the blade 31a of the fan 30 as shown in FIG. A projection 30c for welding is provided on the end of each blade 30a of the fan 30 by pressing for projection welding. The side plate 31 is fixed by projection welding to the end of each blade 30a.

Further, as shown in FIG. 3B, each blade 30a
A welding seat portion 30d is bent and formed in the circumferential direction at the end of the sheet by pressing. A welding projection 30e is provided on the welding seat portion 30d by pressing. This each feather 3
The side plate 31 is projection-welded and fixed to the end of 0a.

Example 3. Although the projection 30c or 30e for welding is provided on the blade 30a in FIG. 3 described above, FIG.
You may provide the welding protrusion 31a in the side plate 31 like (B). The side plate 31 is provided with a welding projection 31a at a required welding position corresponding to the blade 30a by pressing. This side plate 31 is fixed to each blade 30a of the fan 30 by projection welding. As described above, the side plate 31 is attached to the fan 30.
Is firmly fixed with high productivity. The fan 32 also has the above-mentioned 3
Similar to 0, the side plate 33 is fixed to the blade 32a by projection welding.

[0020]

As described above, according to the present invention, the side plate is fixed to the end of the blade of the fan, and the difference between the inner radius of the side plate and the inner radius of the intake hole of the bracket is made larger than the blade width. And since the inner radius of the side plate was made smaller than the outer radius of the intake hole,
The air volume is increased and the noise caused by wind noise is reduced. According to the second aspect of the invention, the side plate is fixed to the end portion of the fan blade with high productivity.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a vehicle generator according to a first embodiment of the present invention.

2A and 2B are front views of the front fan and the rear fan of FIG.

3 (A) and 3 (B) are perspective views showing each example in which a blade for welding is provided on a blade of a fan before showing Embodiment 2 of the present invention.

4 (A) and 4 (B) are a front view and a sectional view of a side plate to be welded to a blade of a fan before showing another example according to Embodiment 3 of the present invention.

5A and 5B are a vertical sectional view and a front view of a conventional vehicle generator.

[Explanation of symbols]

 1 Stator 4 Rotor 5, 6 Magnetic pole core 7 Excitation coil 8 Rotation axis 12 Front bracket 12a Intake hole 12b Exhaust hole 13 Rear bracket 13a Intake hole 13b Exhaust hole 15, 16 Bearing 30 Front fan 30a Blades 30c, 30e For welding Protrusion 31 Side plate 31a Welding protrusion 32 Rear fan 32a Blade 33 Side plate

Claims (2)

[Claims] 1. A stator coupled to a front bracket and a rear bracket, and a stator fixed to a rotating shaft supported by bearings on both brackets, and a plurality of pairs of magnetic poles are formed in the circumferential direction to form an exciting coil. A rotor having a magnetic pole core held therein and a pair of front and rear fans attached to both ends of the magnetic pole core are provided, and each of the brackets has a plurality of intake holes at its end and a plurality of air holes at its outer periphery. In a vehicular AC generator in which exhaust air holes are provided and the inside of the fan is cooled by the rotation of the rotor with a fan, the fan has a side plate fixed to the end of the blade, and at least one of the fans is The front fan is characterized in that the difference between the inner radius of the side plate and the inner radius of the intake hole of the corresponding bracket is made larger than the blade width and the inner radius of the side plate is made smaller than the outer radius of the intake hole. Generator. 2. A stator connected to a front bracket and a rear bracket, and a stator fixed to a rotating shaft supported by bearings on both brackets, and a plurality of pairs of magnetic poles are formed in the circumferential direction to form an exciting coil. A rotor having a magnetic pole core held therein and a pair of front and rear fans attached to both ends of the magnetic pole core are provided, and each of the brackets has a plurality of intake holes at its end and a plurality of air holes at its outer periphery. In a vehicular AC generator in which the exhaust holes are provided and the inside of the fan is cooled by the rotation of the rotor by a fan, a welding projection is provided on either one of the end of each blade of the fan or the corresponding side plate. An alternator for a vehicle, wherein a side plate is provided and fixed to a fan blade end by projection welding.