JPH11178281A - Totally-enclosed fan-cooled electric rotating machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a totally-enclosed fan-cooled electric rotating machine, the internal temperature of which is made uniform, so as to suppress the local degradation of an electrical insulating material or the like and whose life can be prolonged. SOLUTION: A totally-enclosed fan-cooled electric rotating machine is provided with an outer fan 23 on end side (on the side opposite to its connection) in the axial direction. The totally-enclosed fan-cooled electric rotating machine is constituted, in such a way that a heat dissipating finned part 32 on the outer circumference of a motor body is divided into an intake side A and an evacuation side B by a lower wind guide 25 and that the ventilation direction of a cooling wind taken into from the other end side in the axial direction by the outer fan 23 faces opposite on the intake side A and the evacuation side B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fully-closed external fan-type rotating electric machine, and more specifically, to extend the service life of the fully-closed external fan-type rotating electric machine by devising a cooling structure thereof.

[0002]

2. Description of the Related Art FIG. 5 is a side view of a conventional fully enclosed fan-shaped electric motor, partially cut away. As shown in FIG. 1, the fully-closed outer fan-shaped electric motor 1 includes an outer fan 3 at one end in the axial direction (opposite to the coupling side). A ventilation inlet 5 is provided at an end surface of the outer fan cover 4 that covers the outer fan 3, and a ventilation outlet 8 is provided at the other axial end (connection side).

[0003] Further, a heat radiation fold 6 is provided on a jacket (frame) of the motor body 2. The heat-dissipating folds 6 are provided with a large number of heat-dissipating folds (cooling fins) 6a formed along the axial direction at predetermined intervals in the circumferential direction. Reference numeral 10 in the figure denotes an umbrella provided for sun protection or rain protection, which covers the upper half of the outer periphery of the motor body.
Also, 7 in the figure is a frame leg for supporting the motor body 2,
Reference numeral 9 denotes a rotating shaft of the motor body 2 rotatably supported by bearings 11 and 12. The above-described outer fan 3 has a rotating shaft 9
Is joined to.

Therefore, according to the fully-closed outer fan-shaped electric motor 1 having the above-described structure, the electric motor main body 2 is activated and the outer fan 3 is driven together with the rotating shaft 9.
Is rotated, air is taken in from the ventilation inlet 5 on the non-connection side, and the taken-in cooling air flows in one direction through the radiating fold 6 of the motor body 2 and is discharged from the ventilation outlet 8 on the connection side.
That is, in the conventional fully-closed external fan-type electric motor 1, one-way ventilation is performed on the entire circumference. At this time, the heat transmitted from the inside of the motor body 2 is radiated to the cooling air.

[0005]

However, in the above-mentioned conventional fully-closed external fan-type electric motor 1, since the air flows in one direction in the entire circumference, the anti-connection side (the outer fan 4 side) cools well, but the connection side has a relatively low temperature. Will be expensive. That is, while the cooling wind absorbs heat radiation while flowing through the heat radiation folds 6 of the motor body 2, the temperature rises, so that on the connection side, the amount of heat transmitted from the inside of the motor body and radiated to the cooling wind decreases. . Therefore,
The temperature of the connection side is higher by 10 to 15 ° C. in the coil temperature inside the motor body than that of the anti-connection side.

For this reason, the thermal deterioration (life) of the coil insulating material, the bearing 12 and its lubricant mainly on the connection side is accelerated as compared with that on the non-connection side. Since the life of the motor is determined by the local thermal deterioration (life) of the coil insulating material and the like, there is a certain limit even in a long life design.

FIG. 2 shows an example of the life of the epoxy insulating material (a general concept). As shown in FIG. 2, the thermal deterioration (lifetime) of the electrical insulating material and the bearing grease is 10 ° C.
Half-life theory (If the operating temperature rises by 10 ° C, the life will be halved)
Is generally known. As described above, the life of a rotating electric machine often depends on the deterioration of the electric insulating material. When the life of the electric insulating material reaches the end of its life, the life of the electric insulating material can be restored only by completely repairing the electric insulating material. Since the life of the bearing and its lubricant also depends on the operating temperature, it is important to design the bearing to minimize the maximum temperature.

Accordingly, the present invention has been made in view of the above-mentioned prior art, and has as its object to provide a totally enclosed external fan-type electric rotating machine capable of equalizing the internal temperature, suppressing local deterioration of an electrically insulating material or the like, and extending the life. Make it an issue.

[0009]

According to the present invention, there is provided a fully-closed external fan-type rotary electric machine in which an external fan is provided at one end in an axial direction. The cooling fan is divided into an intake side and an exhaust side, and the ventilation direction of the cooling air sucked in from the other end in the axial direction by the outer fan is configured to be opposite between the intake side and the exhaust side.

Therefore, according to this fully enclosed outer fan type rotary electric machine, the heat radiation folds on the outer periphery of the rotary electric machine main body are divided into an intake side and an exhaust side, and the cooling fan sucked from the other end in the axial direction by the external fan has a ventilation direction. Are arranged so that the intake side and the exhaust side are opposed to each other, so that the amount of heat released to the cooling air is leveled and the internal temperature is made uniform as compared with the related art.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a sectional view of a fully-closed external fan motor according to an embodiment of the present invention, FIG. 2 is a sectional view taken along line II-II of FIG.
FIG. 3 is a sectional view taken along the line III-III of FIG. 1, and FIG. 4 is an explanatory view showing variations of a method of dividing the intake side and the exhaust side.

As shown in FIG. 1, a fully-closed external fan motor 21
Has an outer fan 23 at one end in the axial direction (opposite side of connection). As shown in FIGS. 1 and 2, the outer fan 23 is covered by an outer fan cover 27 and faces a blade core (boss) 23 a, a main plate 23 b fixed to the blade core 23 a, and an inner surface of the main plate 23 b. Shroud 23d provided as a main plate 23b
Blade pieces 2 interposed between the blade and the shroud 23d
3c, the rotating shaft 2 of the motor body 22 having a blade core 23a rotatably supported by bearings 28 and 29.
4.

As shown in FIGS. 1 and 3, a radiating fold 32 is provided on a jacket (frame) of the motor body 22. A large number of heat radiation folds (cooling fins) 32a formed along the axial direction are provided on the heat radiation fold portion 32 at predetermined intervals in the circumferential direction. Incidentally, reference numeral 33 in the figure denotes an umbrella provided for sun protection or rain protection, and covers the upper half of the outer periphery of the motor body. 34 in the figure.
Are frame legs for supporting the motor body 22.

As shown in FIGS. 1 and 2, a downwind guide 25 is interposed between the outer fan 23 and the motor body 22 on the opposite side of the connection. The lower wind guide 25 has an arc shape and is fixed to a lower portion of the end face of the electric motor body 22. Therefore, as shown in FIGS. 1 and 3, the heat radiation fold 32 on the outer periphery of the electric motor body is divided into an upper intake side A and a lower exhaust side B by the downwind guide 25. The reason why the exhaust area on the exhaust side B is made larger than the intake area on the intake side A is that the frame leg 34 on the exhaust side B blocks a part of the ventilation path on the exhaust side B, so that This is taken into account, and the air distribution between the cooling folds 32a on the intake side A and the exhaust side B is made equal to each other so that the wind speed is the same.

An upper wind guide 26 is provided between the shroud 23 d of the outer fan 23 and the outer fan cover 27.
The upper wind guide 26 is in the shape of an arc and the lower wind guide 25
And both ends are fixed to both ends of the downwind guide 25.

Therefore, according to the fully enclosed fan-type electric motor having the above-described structure, the electric motor main body 22 is activated and the electric motor 22 is rotated together with the rotating shaft 24 as shown by arrows and the like in FIGS. When the outer fan 23 provided on the connection side rotates, air is taken in from the ventilation inlet 30 on the connection side, and the taken-in cooling air is
Flows from the connection side to the anti-connection side through the intake side A,
On the non-connection side, it is guided to the outer fan 23 by the upper wind guide 26, and then guided to the exhaust side B by the lower wind guide 25 from the outer fan 23, and the exhaust side B flows from the non-connection side to the connection side. The air is exhausted from the ventilation outlet 31. That is, the ventilation direction of the cooling air taken in from the connection side is opposed to the intake side A and the exhaust side B.

As a result, the maximum temperature is suppressed as much as possible (the average temperature is the same as in the conventional case), that is, the amount of heat radiated to the cooling air is leveled and the internal temperature is made uniform. Therefore, it is possible to suppress the deterioration of the local electric insulating material, the bearing and the lubricant thereof, and to prolong the service life. That is, the cooling performance of the motor is improved, and the reliability and the service life can be extended.

When the radiating fold 32 is divided into the upper intake side A and the lower exhaust side B as described above, if there is a difference in ventilation temperature in the vertical direction, the lower side of the motor will reach the maximum temperature. It is conceivable that the stator core has sufficient heat conduction in the circumferential direction in combination with sufficient circulation ventilation inside the motor, so that there is almost no vertical temperature difference. on the other hand,
Since the stator core is formed by laminating a number of thin iron plates in the axial direction, the heat transfer in the axial direction is extremely poor.

In the above description, the upper part of the heat radiation fold 32 is the intake side A and the lower part is the exhaust side B. However, the present invention is not limited to this, and the way of dividing the intake side A and the exhaust side B is appropriately selected. can do. For example, as shown in FIG. 4A, the left side of the heat radiation fold 32 is taken as the intake side A and the right side of the heat radiator 32 is taken as the exhaust side B, or as shown in FIG. The lower part may be the intake side A and the upper part may be the exhaust side B.

Further, all the cooling air may be sucked from the connection side, or a part of the cooling air may be sucked.

[0022]

As described above in detail with the embodiments of the present invention, according to the fully enclosed fan-shaped rotary electric machine of the present invention, the heat radiation folds on the outer periphery of the rotary electric machine main body are divided into the intake side and the exhaust side. In addition, since the ventilation direction of the cooling air sucked from the other end in the axial direction by the external fan is configured so as to oppose the intake side and the exhaust side, the amount of heat radiation to the cooling air is leveled compared to the related art. Thus, the internal temperature is made uniform. Therefore,
It is possible to suppress the deterioration of the local electric insulating material, the bearing and the lubricant thereof, and to prolong the service life. That is, the cooling performance of the rotating electric machine is improved, and the reliability and the service life can be extended.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a fully-closed external fan motor according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a sectional view taken along line III-III of FIG. 1;

FIG. 4 is an explanatory diagram showing variations of how to classify an intake side and an exhaust side.

FIG. 5 is a partially cutaway side view of a conventional fully enclosed fan-type electric motor.

FIG. 6 is an explanatory diagram showing an example of the life of the epoxy insulating material (general concept).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 21 Fully enclosed outer fan motor 22 Motor body 23 Outer fan 23a Blade core 23b Main plate 23c Blade piece 23d Shroud 24 Rotating shaft 25 Downwind guide 26 Upper wind guide 27 Outer fan cover 28, 29 Bearing 30 Ventilation inlet 31 Ventilation outlet 32 32a Heat radiation fold 33 Parasol 34 Frame leg

Claims (1)

[Claims] 1. A fully-closed external fan-type rotary electric machine having an external fan at one end in an axial direction, wherein a radiating fold on an outer periphery of the rotary electric machine body is divided into an intake side and an exhaust side, and the other end in the axial direction is formed by the external fan. A fully enclosed fan-shaped rotary electric machine characterized in that the ventilation direction of the cooling air taken in from the air is opposed on the intake side and the exhaust side.