JPH0549216A - Frame for rotating electric machine - Google Patents

Abstract

PURPOSE:To obtain a frame for a rotary electric machine, which is capable of improving the cooling efficiency of the main body of the rotating electric machine and miniaturizing the same, by a method wherein an air guiding section, preventing cooling air from escaping to the outside in radial direction, is provided on one part in the axial direction of heat dissipating fins. CONSTITUTION:A frame 3 is provided with an air guiding section 17 preventing cooling air from escaping to the outside in radial direction. Cooling air, sucked by the rotation of an external fan 13, is guided to a fan cover 14 and a ventilating duct 16a, then, is discharged from a tapered section 18a, provided near the outlet port of the ventilating duct 16a to the outer peripheral section of the frame 3 and the surfaces of heat dissipating fins 2a. Most of the cooling air passes through the ventilating duct 16a without escaping to the outside in the radial direction while the cooling air, discharged out of the ventilating duct 16a, is guided by a tapered section 18a to flow toward the surface of the frame near the center of the same once and flows between neighboring heat dissipating fins 2a along the surface of the frame 3 while changing the flow direction after colliding against the surface of the frame 3. Accordingly, a high heat conductivity can be obtained without reducing the air speed of the cooling air.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a frame of a rotary electric machine.

[0002]

2. Description of the Related Art A conventional rotary electric machine of this type will be described with reference to FIG. In FIG. 6, reference numeral 1 denotes a rotating electric machine main body in which a thin steel plate is formed into a tubular shape, and a large number of strip-shaped heat radiation fins 2 are welded and welded to the outer peripheral surface of the frame 3, and the frame 3 is attached to both left and right end portions of the frame 3. Bearing brackets 4, 5
The inside is hermetically sealed by an outer shell 6 composed of A stator core 7 is press-fitted and fixed in the outer shell 6, and a stator winding 8 is attached to the stator core 7. A rotary shaft 9 is rotatably supported on the left and right bearing brackets 4 and 5 of the outer shell 6 via bearings 10 and 10, respectively, and a rotor core 11 rotates integrally with the rotary shaft 9. It is installed to do. 12 is a blade as an internal fan. An external fan 13 is attached to a part of the rotary shaft 9 that projects from the left bearing bracket 5 so as to rotate integrally with the rotary shaft 9. An intake port 15 for cooling air is provided in the center on the left side of the fan cover 14 that covers the external fan 13, and an opening for the cooling air is opened on the right side. The arrows indicate the direction of cooling air flow.

[0003]

In the above configuration,
Most of the heat generated in the rotating electric machine main body 1 is the stator core 7
Is transmitted directly to the frame 3. On the other hand, the heat transferred to the frame 3 is directly or through the heat radiation fins 2 from the intake port 15 to the fan cover 14 by the external fan 13.
The rotating electric machine main body 1 is cooled by being discharged into the outside air by the cooling air that is sucked in and is fed from the open end (outlet) side to the outer peripheral portion of the frame 3. Therefore, the rotating electric machine body 1
Most of the heat generated inside is finally released from the frame 3 to the outside air by the cooling air, so the cooling efficiency in such a rotating electric machine is determined by the heat radiation ability from the frame 3 to the cooling air. ..

By the way, since the cooling air fed from the outlet side of the fan cover 14 having such a conventional structure to the outer peripheral portion of the frame 3 tends to flow toward the side having a smaller ventilation resistance, a part of the cooling air is the same. As shown in the figure, it escapes to the outside of the frame 3 in the radial direction. Therefore, a part of the cooling air does not contribute to the cooling of the rotary electric machine body 1, so that there is a drawback that the cooling efficiency cannot be sufficient.

In order to deal with this, for example, as shown in FIG. 7, it is conceivable to bend the entire radiation fin 2 and form a ventilation duct 16 between the radiation fin 2 and the adjacent radiation fin 2 (Actual Publication No. 51-32886). , Jitsukai Sho 62-1224
49). However, in this case, since the ventilation duct 16 is formed over the entire length of the radiating fin 2, the loss head from the inlet to the outlet of the ventilation duct 16 becomes large and the total cooling air volume is considerably reduced. Therefore, the cooling efficiency may be deteriorated as compared with the case of FIG.

Therefore, an object of the present invention is to improve the cooling efficiency of the rotating electric machine main body by making the cooling air blown out from the fan cover contribute to the cooling of the rotating electric machine main body, thereby reducing the size of the rotating electric machine. To provide the frame.

[0007]

According to the present invention, a thin steel plate is formed in a cylindrical shape, and a frame having a large number of heat radiation fins welded to its outer peripheral surface is welded to a frame and a rotary shaft protruding to the outside of the frame. A rotating electrical machine frame, comprising an attached external fan and a fan cover for covering the external fan, wherein cooling air sucked by the external fan is fed from the fan cover to the outer peripheral portion of the frame. An air guide portion that prevents the cooling air from escaping radially outward is provided in a part of the radiating fin in the axial direction near the fan cover. Further, a taper portion is provided such that a part or the whole of the air guide portion is closer to the surface of the frame as the cooling air is downwind.

[0008]

By preventing the cooling air from escaping to the outside in the radial direction, the cooling air is made to be an effective flow along the outer peripheral surface of the frame and the heat radiation fins without lowering the speed of the cooling air. Increase. Therefore, extremely effective cooling can be performed, and downsizing of the rotating electric machine body can be realized.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing an upper half of an embodiment of the present invention by cutting. The same parts as those of the conventional structure are designated by the same reference numerals, and the description of the same parts will be omitted.

In the structure of FIG. 1, reference numeral 17 denotes an air guide portion which prevents the cooling air from escaping radially outward. Again 1
Reference numeral 8a denotes a taper portion, which is closer to the surface of the frame 3 as the cooling air is further downwind. FIG. 2 is a perspective view of the heat radiation fin 2a. A large number of radiating fins 2a are welded to the outer peripheral surface of the frame 3 by welding, and a short ventilation duct 16a is formed between adjacent radiating fins 2a.

Next, the operation of the embodiment having the above configuration will be described. The cooling air sucked from the outside by the rotation of the external fan 13 is guided to the fan cover 14 and the ventilation duct 16a, and from the tapered portion 18a provided near the outlet of the ventilation duct 16a to the outer peripheral portion of the frame 3 and the radiation fin 2a.
Is ejected onto the surface of. Most of the cooling air passes through the ventilation duct 16a without escaping to the outside in the radial direction. Therefore, in addition to the surfaces of the frame 3 and the radiation fins 2a, which are the inner surfaces of the ventilation duct 16a, the air guide portion 17 and the tapered portion 18a.
A high heat transfer coefficient is obtained at. Further ventilation duct 1
The cooling air discharged from 6a is once directed to the surface near the center of the frame by the tapered portion 18a, hits the surface of the frame 3 and then changes its direction, and the space between the adjacent radiating fins 2a along the surface of the frame 3 is changed. Flowing through. For this reason, the cooling air flows effectively without lowering the wind speed, so that a high heat transfer coefficient can be obtained.

Therefore, in the above-described embodiment, the cooling air is effectively flowed over the entire length of the frame 3 and the radiation fins 2a including the inside of the ventilation duct 16a without lowering the wind speed, so that the heat transfer coefficient is increased. The cooling efficiency of the rotating electrical machine body 1 can be improved. (Other embodiments)

FIG. 3 is a sectional view showing an upper half of another embodiment of the present invention by cutting it, and FIG. 4 is a perspective view of a heat radiation fin 2b. Reference numeral 17 denotes an air guide portion, which prevents the cooling air from escaping in the radial direction and forms a short ventilation duct 16b between the adjacent heat radiation fins 2b. The radiating fins 2b are raised in the leeward direction from the outlet of the ventilation duct 16b.

In this structure, the cooling air discharged from the ventilation duct 16b gradually goes to the outside in the radial direction, but since the radiation fins 2b are raised, the cooling air flows between the radiation fins 2b over the entire length of the frame 3. The cooling air can be effectively contributed. Further, since the heat radiation area is large, it is possible to obtain a cooling efficiency equal to or higher than that of the embodiment of FIGS. The radiation fin 2b is shown in FIG.
Bend the end of the air guide portion 17 as shown in FIG.
8b may be molded.

[0015]

As described above, according to the present invention, almost all of the cooling air can contribute to the cooling of the rotating electric machine body, so that the cooling efficiency of the rotating electric machine body is improved,
It is possible to provide a frame of a rotating electric machine that is downsized.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an upper half of an embodiment of the present invention by cutting it,

2 is a perspective view of the radiation fin of FIG. 1,

FIG. 3 is a sectional view showing the upper half of another embodiment of the present invention by cutting the upper half;

4 is a perspective view of the radiation fin of FIG. 3,

5 is a perspective view showing a modified example of the radiation fin of FIG. 4,

FIG. 6 is a cross-sectional view showing an upper half of a conventional fully-closed fan-type rotating machine,

FIG. 7 is a perspective view showing a frame of another conventional fully-closed outer fan-shaped rotating electric machine.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Rotating electric machine main body 2, 2a, 2b ... Radiating fin 3 ... Frame 9 ... Rotating shaft 13 ... External fan 14 ... Fan cover 17 ... Wind guide part

Claims (1)

[Claims] 1. A frame in which a thin steel plate is formed in a tubular shape, and a large number of heat radiation fins are welded to the outer peripheral surface of the frame by welding.
An external fan attached to a rotating shaft protruding to the outside of the frame and a fan cover for covering the external fan are provided so that the cooling air absorbed by the external fan is fed from the fan cover to the outer peripheral portion of the frame. In the frame of the rotating electric machine according to claim 1, an air guide portion for preventing cooling air from escaping radially outward is provided in a part of the heat dissipating fin in the axial direction near the fan cover. ..