JPS60257738A - Cooling structure of underliquid rotary electric machine - Google Patents

Abstract

PURPOSE:To enhance the cooling efficiency by inclining an inlet or an outlet of a passage for alternately axially flowing in a rotor in a circumferential direction. CONSTITUTION:Rotor shaft direction passages 81, 82 provided in a rotor core 5 and a rotor core retainer 7 are alternately disposed, and liquid in a rotary electric machine flows in right and left shaft directions by inclining an inlet or an outlet in a circumferential direction. As a reult, in a loss generated in a rotary electric machine the efficiency for transmitting heat to the inner liquid is enhanced. Since the liquid is flowed to the rightward and leftward, the liquid is not stayed. Since the right and left sides are uniformly cooled, the temperatures are uniform, and cooling efficiency can be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a rotating electric machine used in liquid, and more particularly to a cooling structure for a rotating electric machine having alternating axial passages.

[Background of the invention]

Figure 1 shows the structure of a conventional submerged rotating electric machine.

The rotating electric machine is covered with a stator frame 1, and both the inside and outside are immersed in liquid. It has a stator core 2 attached to a stator frame 1 and a stator winding 3 disposed on the stator core 2. In addition, in a rotating electric machine having a trochanter core presser 7 installed on one rotor shaft 4 and two rotor windings 6 arranged on the rotor core 5, the stator core 2, the stator winding 3, the rotor core 5,
The loss generated in the rotor winding 6 and the stirring loss due to rotation are transferred to the stator frame 1, and further cooled by heat transfer to the outside from the stator frame 1. Since most of the heat is generated in the axial center, the temperature is high in the center, resulting in a low overall cooling effect and a high-temperature rotating electrical machine.

To compensate for this drawback, there has conventionally been a rotating electric machine having the structure shown in FIG. The difference from Fig. 1 is the rotor core 5.
and a rotor axial passage 8 provided in the rotor core holder 7. Providing the rotor axial passage 8 has the effect of lowering the temperature at the axial center mentioned above. However, this structure has the drawback that sufficient cooling cannot be achieved because the liquid flowing in the axial direction stays on one side.

To compensate for the drawbacks shown in FIG. 2, there is a conventional rotating electric machine having a structure shown in FIG. 3. The difference is that a sub-connection pipe 9 different from that shown in FIG. 2 is provided. As a result, there is no stagnation in one side, which is a drawback in FIG. 2, and cooling efficiency is improved by the circulating cold body.

However, in this structure, since cooling is performed in the axial direction, there is a drawback that the temperature difference in the axial direction is large and the maximum temperature is high. Furthermore, since the stator communication pipe 9 is attached outside the stator frame 1, there are many components, and there is a high probability of pipe breakage, etc., resulting in low reliability.

Furthermore, to compensate for the drawbacks of FIGS. 2 and 3, there is a conventional rotating electric machine having a structure shown in FIG. 4.

(Japanese Publication No. 14-1.056) The difference from Fig. 2 is that the axial passage 8 is constituted by a shaft arm provided on the inner circumferential side of the rotor core 5, and a cover plate is provided at the end. 10 and a cooling fan Ij, and by flowing the internal fluid alternately in the axial direction, there is an effect of reducing temperature rise. However, in this structure, the number of attached parts increases, the probability of accidents due to failure is high, and since the axial passage 8 is located on the inner circumferential side of the rotor core 5, the construction and machine size become large. Furthermore, since the axial passage is an arm to the shirt 1, there is a drawback that loss occurring in the rotor winding 6 and the rotor core 5 cannot be effectively cooled down.

[Purpose of the invention]

An object of the present invention is to provide a cooling structure for a submerged rotating electrical machine that increases cooling efficiency and improves reliability by eliminating stator communication pipes, cover plates, and cooling fans.

[Summary of the invention]

The gist of the present invention is to provide a structure in which the entrances or exits of the axial passages are inclined on the circumference and pass through alternately in the axial direction, thereby improving cooling performance and improving reliability by reducing the number of parts.

[Embodiments of the invention]

An embodiment according to the invention is shown in FIG. The rotor axial passages (direction A) 8] and the rotor axial passages (direction B) 82 provided in the rotor core 5 and the rotor core holder 7 are arranged alternately as shown in the development diagram shown in FIG. By tilting the inlet or outlet in the circumferential direction, the internal liquid of the rotating electric machine flows in the left and right axial directions.

As a result, the loss generated in the rotating electric machine is transferred more efficiently to the internal liquid, and since the internal liquid flows from side to side, it does not stagnate in one direction, and the temperature on the left and right sides is cooled evenly. Therefore, the temperature is low and the cooling efficiency is excellent. In addition, conventionally, circulation of internal liquid from side to side was carried out using a stator chain, 18 tubes, cover plate, or cooling fan installed outside the stator frame, but by eliminating these components, , it is possible to prevent a decrease in reliability due to component breakage.

C Effects of the Invention] According to the present invention, there is an effect of increasing the cooling efficiency and lowering the temperature, and it is also possible to eliminate accidents such as parts breakage.
Improved reliability.

[Brief explanation of the drawing]

1 to 4 are partial sectional views of a conventional rotor, FIG. 5 is a partial sectional view of an embodiment of the present invention, and FIG. 6 is a developed view of the rotor axial passage portion of FIG. 5. 8... Rotor axial passage, 9 Stator communication pipe, 81° [-I/ \,. III Figure 2 Figure 3) i = Hase - Yu

Claims (1)

[Scope of Claims] 1. A structure in which passages are provided that alternately flow in the axial direction of a rotor of a rotating electric machine operating in liquid. A cooling structure for a submerged rotating electric machine, wherein the inlet and/or outlet of the axial passage is inclined in the circumferential direction.