JPH0993868A - Main motor for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low noise self-ventilated main motor for vehicle which can deal with high capacity while enhancing the efficiency of axial fan. SOLUTION: The guide ring 5 of axial fan 4A, 4B is cut off by a specified length and brought close to a short-circuit ring 8 and the inside diameter of guide ring 5 is set substantially equal to that of the short-circuit ring 8 thus suppressing the level difference. Consequently, vortex is eliminated, at the intake port and exhaust port of axial fan 4A, 4B and the efficiency thereof is enhanced. When wind holes 9 are made through the rotor core 1 at the positions corresponding to the blades 6 of axial fan 4A, 4B, the cooling air flow is made uniform and the noise is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a self-ventilated vehicular main motor such as an induction motor mainly used for driving an electric vehicle.

[0002]

2. Description of the Related Art A radial fan is generally used as a cooling fan for a main motor for a self-ventilated vehicle. In the case of a radial fan (not shown), the ventilation volume is almost proportional to the rotation speed of the fan and the outer diameter of the fan blades. Therefore, when the electric vehicle travels at high speed, the current of the main motor is small, and therefore the cooling air flow amount may be small, but the air flow amount becomes unnecessarily large, and the wind noise significantly increases accordingly. It was an obstacle to noise reduction. Therefore, we have proposed a self-ventilated vehicle main motor that has axial fans on both sides of the rotor core first, as a self-ventilated vehicle main motor that can reduce noise while ensuring the required cooling airflow. did.

FIG. 6 is a view showing a cross section of the above-described self-ventilated vehicular main electric motor in which two axial fans are arranged. Figure 6
In the figure, 1 is a rotor core, 2 is a shaft, 3A and 3B are vents, 4A and 4B are axial fans, 6 is blades of axial fans, and 10
Is a bracket, 11 is a bearing box, and 9 is an air hole provided in the rotor core. When the axial fans 4A and 4B fixed to the shaft 2 rotate, cooling air is circulated in the main electric motor for cooling. To do. The axial fans 4A and 4B are the rotor core 1
Are arranged on both sides of the fan and the axial fans 4A, 4B
The blades 6 of the above-mentioned blades have substantially the same inclination with respect to the longitudinal direction of the shaft 2 so that the mutual ventilation effect works. In addition, the diameter of the guide ring 5 of the axial fan is made large in order to secure the ventilation volume as much as possible. Therefore, the inner diameter of the guide ring 5 is considerably larger than the inner diameter of the short-circuit ring 8. .

In the above structure, when the main electric motor for a vehicle is rotating in a certain direction, the cooling air is introduced from the ventilation port 3B at one end of the machine by the discharging action of the axial flow fan 4A and the pushing action of the axial flow fan 4B. As shown by the broken line arrow in FIG. 6, the air gap 9 between the rotor core and the gap between the stator and the rotor.
12 and the like are circulated and discharged from the ventilation port 3A on the other end side of the machine. On the other hand, when the vehicle main electric motor is rotating in the other direction, for example, the discharging action of the axial flow fan 4B and the axial flow fan 4A.
The cooling air is blown by the pushing action of
It is introduced from A, flows through the air holes 9 of the rotor core, the gap 12 between the stator and the rotor, and the like as shown by the solid arrow in FIG. 6, and is discharged from the ventilation port 3B on one end side in the machine. Due to the above-described ventilation action, cooling air flows through the inside of the vehicle main electric motor, and the main electric motor can be cooled regardless of the rotation direction. At that time, the cooling air volume can be secured by using two axial fans that work well in ventilation, and because the axial fan is more efficient than the conventional radial fan, the blades of the axial fan are The outer diameter can be made smaller than that when a radial fan is used, and wind noise can be reduced.

[0005]

An axial fan is a fan that has a characteristic that the static pressure is low and the air volume is large, and when it is installed inside the main motor, the air flow rate changes due to a slight change in the ventilation resistance inside the machine. Change significantly. In the vehicular main electric motor shown in FIG. 6, the diameter of the guide ring of the axial fan has been increased in order to secure as much ventilation as possible. It was found that the step difference of the shape became large between the inner diameter dimensions, and as a result, large vortices (a in FIG. 6) were generated at the inlet and outlet of the axial fan inside the machine. Due to the increase in the ventilation resistance due to the generation of the vortex, the effect of increasing the diameter of the guide ring to secure the maximum ventilation amount was hardly obtained, which was an obstacle to the large capacity. The present invention was created in view of the above points,
A first object of the present invention is to make the flow of cooling air inside the main motor a smooth flow without vortices, to effectively secure a necessary cooling air flow and to achieve low noise. To provide the main motor of. Second of the present invention
It is an object of the present invention to provide a self-ventilated main motor that improves the efficiency of an axial fan and can sufficiently cope with a large capacity of the main motor.

[0006]

In order to solve the above-mentioned problems, the invention according to claim 1 of the present invention is such that self-ventilation in which cooling fans are circulated in the machine by disposing axial fans on both sides of the rotor core. -Shaped vehicle main electric motor, the guide ring of the axial fan is cut out by a predetermined length so as to be close to the short-circuit ring, and the inner diameter of the guide ring is approximately the same as the inner diameter of the short-circuit ring. It is composed.

According to a second aspect of the present invention, in the first aspect of the invention, the number of blades of the axial fan on both sides of the rotor core is the same, and the blades are arranged in the circumferential direction in which the blade faces the rotor core. The positions are substantially the same, the number of air holes provided in the rotor core is the same as the number of blades, and the air holes are arranged substantially evenly on the circumference corresponding to each blade. According to a third aspect of the present invention, in the first aspect of the invention, the number of blades of the axial fan on both sides of the rotor core is the same, and the positions of the blades in the circumferential direction facing the rotor core are substantially the same. The number of air holes in the rotor core is n times the number of blades (n
Is a positive integer), and n air holes are arranged substantially evenly on the circumference corresponding to each blade.

[0008]

The operation will be described together with the following embodiment. Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0009]

1 and 2 are views showing a first embodiment of the present invention, FIG. 1 is a sectional view of a vehicular main electric motor showing an embodiment of the present invention, and FIG. It is sectional drawing of the main motor for vehicles which shows another Example, and shows the example which has various shapes and which has a pair of axial fan 4A, 4B arrange | positioned at both sides of the rotor core 1. As shown in FIG. 1 and 2, 1 is a rotor core, 2 is a shaft, 3A and 3B are ventilation holes, 4A and 4B are axial fans, 6
Is an axial fan blade, 10 is a bracket, 11 is a bearing box, 9
Is a wind hole provided in the rotor core, and by rotating the axial fans 4A and 4B fixed to the shaft 2, cooling air is circulated in the main motor for cooling. In the case of FIGS. 1 and 2, the relationship between the number of blades 6 and the number of air holes 9
It is assumed that there is no particular restriction on the positional relationship of the air holes on the wing tip surface.

The axial fans 4A and 4B are arranged on both sides of the rotor core 1, and the blades 6 of the axial fans 4A and 4B have substantially the same inclination with respect to the longitudinal direction of the shaft 2, The mutual ventilation action works in harmony. Also,
The guide rings 5 of the axial fans 4A, 4B are cut out by a predetermined length so as to be close to the short-circuit ring 8, and the inner diameter of the guide ring 5 is made substantially the same as the inner diameter of the short-circuit ring 8. The step difference is kept as small as possible, thereby eliminating the generation of vortices at the inlet and outlet of the axial fan to improve the efficiency of the axial fan, and the flow of cooling air inside the main motor is free of vortices. A smooth flow was created to reduce ventilation resistance and ensure the required amount of cooling ventilation. In addition, the diameter of the guide ring of the axial fan in FIGS. 1 and 2 is smaller than the diameter of the guide ring 5 of the axial fan in FIG. 6, so that the necessary cooling airflow can be effectively secured. In addition, the noise can be reduced.

Next, the ventilation effect in this embodiment will be described. When the rotation direction of the vehicle main motor is in a certain direction, for example, the discharging action of the axial fan 4A and the axial fan 4B are performed.
By the pushing action of the
It is introduced from B and flows through the air holes 9 of the rotor core, the gap 12 between the stator and the rotor, etc., as shown by the broken line arrows in FIGS. 1 and 2, and is discharged from the ventilation port 3A on the other end side in the machine. On the other hand, when the rotation direction of the vehicle main electric motor is the other direction, the cooling air is introduced from the ventilation port 3A on the other end side of the machine by, for example, the discharging action of the axial flow fan 4B and the pushing action of the axial flow fan 4A. 1, as shown by the solid line arrow in FIG. 2, the gas flows through the rotor core 9, the gap 12 between the stator and the rotor, and the like, and is discharged from the ventilation port 3B on one end side in the machine. Cooling air flows through the vehicle main electric motor due to the ventilation effect, and the main electric motor can be cooled regardless of the rotation direction.

FIGS. 3 and 4 are views showing a second embodiment of the present invention, and FIG. 3 is a partially enlarged view of the axial flow fan shown in FIGS. 1 and 2 when viewed from the axial direction. FIG. 4 is a diagram showing the positional relationship between the blades of the axial fan and the air holes of the rotor core in the embodiment of FIG. In each figure, the same reference numerals as those in FIG. 6 denote the same components, 2 is a shaft, 6 is a blade, 9 is a wind hole provided in the rotor core, 5 is a guide ring, 7 is a boss, The axial fans 4A and 4B are composed of blades 6, guide rings 5 and bosses 7 as shown in FIG. As shown in FIGS. 3 and 4, in this embodiment, the number of blades 6 of the axial fan and the number of air holes 9 of the rotor core 1 are the same,
The air holes 9 are arranged substantially evenly on the circumference so as to correspond to the blades 6, and the blade end surfaces of the blades 6 do not overlap the air holes 9. Therefore, the amount of ventilation flowing between the blades of the axial fan becomes uniform, the turbulence of the cooling air can be reduced, and the generation of noise can be suppressed while securing a sufficient amount of ventilation.

FIG. 5 is a diagram showing a third embodiment of the present invention.
FIG. 3 is a partially enlarged view of the axial fan shown in FIGS. 1 and 2 as viewed in the axial direction. In this embodiment, the number of air holes 9 of the rotor core 1 is made to be multiple times the number of blades 6 of the axial fan in the second embodiment, and FIG. The case where the number is three times the number of blades (n = 3) is shown. That is, in this embodiment, as shown in FIG. 5, at the position where the blades 6 of the axial flow fans 4A and 4B face the rotor core 1, a plurality of air holes 9 are formed in the space equally partitioned by the blades. The blades 6 are arranged substantially evenly so that the blade end surfaces of the blades 6 do not overlap the air holes 9. Since the present embodiment is configured as described above, it is possible to reduce the turbulence of the cooling air as in the second embodiment, and to suppress the generation of noise while ensuring a sufficient air flow amount. it can.

Also, since the number of air holes is set to be a multiple of that of the second embodiment, the temperature distribution of the rotor core can be made more uniform than that of the second embodiment by the increased number of air holes. The cooling efficiency can be improved. Although the shape of the air holes is circular in the above-described embodiments, the shape and size of the air holes can be appropriately selected, and the number of air holes can be appropriately selected as necessary. .

[0015]

As described above, the present invention can obtain the following effects. (1) Cut the guide ring of the axial flow fan by a predetermined length so as to be close to the short-circuit ring, and make the inner diameter of the guide ring approximately the same as the inner diameter of the short-circuit ring to minimize the step difference in shape. Keeping the size small, this improves the efficiency of the axial fan by eliminating the generation of vortices at the inlet and outlet of the axial fan, and makes the flow of cooling air inside the main motor smooth and free of vortices. In this way, it is possible to reduce the ventilation resistance and effectively secure the required cooling ventilation volume, and it is possible to sufficiently cope with the increase in the capacity of the vehicle main motor. Further, the diameter of the guide ring of the axial flow fan is small and small, so that noise reduction can be achieved. (2) In the above-configured self-ventilation type main motor for a vehicle, the number of blades of the axial fan on both sides of the rotor core is the same, and the positions of the blades facing the rotor core in the circumferential direction are substantially the same. In addition, the number of air holes provided in the rotor iron core is the same as the number of blades, and the air holes are arranged substantially evenly on the circumference so as to correspond to each blade. It is possible to make the amount of airflow flowing through the airflow uniform, reduce the turbulence of the cooling airflow, and ensure the required amount of airflow, while further reducing noise. Also, by making the number of air holes provided in the rotor core a multiple of the number of blades, the temperature distribution of the rotor core can be made uniform by the increased number of air holes, and each blade of the axial fan can be made uniform. Make the amount of ventilation flowing between the
Moreover, the cooling efficiency can be improved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a vehicle main motor showing an embodiment of the present invention.

FIG. 2 is a sectional view of a vehicular main motor showing another embodiment of the present invention.

FIG. 3 is a partially enlarged view of an axial fan according to an embodiment of the present invention as viewed in the axial direction.

FIG. 4 is a diagram showing the positional relationship between the blades of the axial fan and the air holes of the rotating individual iron core in the embodiment of FIG.

FIG. 5 is a partial enlarged view of an axial fan according to another embodiment of the present invention as viewed in the axial direction.

FIG. 6 is a cross-sectional view of a self-ventilated traction motor for a vehicle in which two axial fans are arranged.

[Explanation of symbols]

 1 rotor core 2 axis 3A ventilation port 3B ventilation port 4A axial flow fan 4B axial flow fan 5 guide ring 6 blade 7 boss 8 short circuit ring 9 air hole 10 bracket 11 bearing box 12 gap a vortex

Claims (3)

[Claims] 1. In a self-ventilation type main motor for a vehicle, in which axial fans are arranged on both sides of a rotor core and cooling air is circulated in the machine, a guide ring of the axial fan is long enough to insert a short-circuit ring. A main motor for a vehicle, characterized in that the guide ring is cut out by a small amount so as to be close to the short-circuit ring, and the inner diameter of the guide ring is approximately the same as the inner diameter of the short-circuit ring. 2. The number of blades of the axial fan on both sides of the rotor core is the same, the positions of the blades in the circumferential direction where the blades face the rotor core are substantially the same, and the air holes provided in the rotor core are The number of blades is the same as the number of blades, and the air holes are arranged substantially evenly on the circumference so as to correspond to the blades.
Main electric motor for vehicle as described. 3. The number of blades of the axial flow fan on both sides of the rotor core is the same, and the positions of the blades in the circumferential direction where the blades face the rotor core are substantially the same. 2. The vehicle according to claim 1, wherein the number of blades is n times (n is a positive integer), and n air holes are arranged substantially evenly on the circumference corresponding to each blade. The main motor.