JP3222242B2 - Liquid-cooled induction motor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small, high-output liquid-cooled induction motor.

[0002]

2. Description of the Related Art (1) A method of exchanging heat by injecting a circulating liquid into a rotor side or a stator side of an electric motor is often used. In this way, the heat generated by the motor can be transferred to the coolant and discharged outside the motor, and the size of the motor can be reduced for the same output of the motor. (2) The present inventor has devised a fully-closed liquid cooling type electric motor disclosed in Japanese Utility Model Laid-Open No. 63-109569.
This electric motor is configured to replace the heat generated by the electric motor with latent heat of condensation of the liquid and discharge it to the cooling liquid.

[0003]

In the case of the electric motor (1), since the heat transfer area cannot be increased, there is a disadvantage that the amount of heat exchange does not increase. Further, in the case of the motor (2), although the motor is improved over the motor (1), the heat exchange amount cannot be expected to be so large. The cause is that the heat exchange area between the evaporation / condensation chamber in the rotor shaft and the liquid injection from the outside depends on the shaft support parts at both ends of the rotor, so it cannot be made too large, There is a limit in trying to release the latent heat.

[0004]

SUMMARY OF THE INVENTION The foregoing problems are advantageously solved.
In order to achieve this, the present invention
Is provided with a vacuum-sealed annular evaporation / condensation chamber 2 for evaporating / condensing
A cooling liquid chamber 4 is provided inside the constriction chamber 2 inside the rotor shaft,
A drain impeller 6 is provided in a liquid chamber 5 connected to an end of the chamber 4.
A liquid-cooled induction motor, which
Coolant 3 is continuously injected into coolant chamber 4 by high-speed jet
Then, the coolant 3 colliding with the other end of the coolant chamber 4 is centrifugally applied.
Characterized in that it is deflected toward the evaporation / condensation chamber 2 and flows
And That is, in the liquid-cooled induction motor of the present invention, the inside of the rotor has a double cooling structure, the outside is a vacuum-sealed annular evaporation / condensation chamber 2, and the inside uses a cavity inside the rotor shaft. Thus, the cooling liquid chamber 4 is formed.

[0005]

1 shows a vertical liquid-cooled induction motor according to an embodiment of the present invention.
Is provided with a cooling liquid chamber 4 extending in the longitudinal direction of the rotor shaft 7, and an annular evaporating / condensing chamber 2 surrounding the cooling liquid chamber 4 is provided.
The inside of the evaporation / condensation chamber 2 is evacuated and contains therein a liquid composed of a small amount of distilled water.

An inlet 10 for injecting a cooling liquid 3 such as water is provided at a lower end of a stator cooling jacket 9 surrounding the stator 8, and one end of a liquid feed pipe 11 is provided at an upper end of the stator cooling jacket 9. The other end of the liquid feed pipe 11 is disposed so as to open downward at the center of the inside of the upper end of the coolant chamber 4 in the rotor shaft 7 so as to open downward.
A drain hole 12 is provided between the other end of the cooling liquid chamber 1 and the upper end of the cooling liquid chamber 4.

A drain impeller 6 is fixed to the upper end of the rotor shaft 7, and a drain port 13 is provided in the liquid chamber 5 surrounding the drain impeller 6. A cooling impeller 14 is fixed at a position opposed to both ends of the motor, and a motor fixing member 15 is attached to the side of the stator cooling jacket 9.

In the evaporation / condensation chamber 2, the liquid inside the evaporation / condensation chamber 2 is collected on the outer inner wall surface by centrifugal force of rotation.
It evaporates by the heat of the rotor 1 and moves inward. Therefore,
Evaporation / condensation chamber 2 cooled by cooling liquid 3 in cooling liquid chamber 4
The liquid inside condenses and releases latent heat. The condensed liquid in the evaporation / condensation chamber 2 moves outward again by centrifugal force. In this way, heat transfer is performed with the liquid in the evaporation / condensation chamber 2 constantly moving outward.

In the cooling liquid chamber 4, the cooling liquid 3 is injected by a high-speed jet from the shaft end of the rotor shaft 7, and the liquid that collides with the other end of the cooling liquid chamber 4 is centrifugally generated by rotation to evaporate and condense the liquid. Gathers on the wall close to the surface, receives the latent heat and forms a swirling flow to increase the residence time.
Is discharged to the outside of the electric motor by the drain impeller 6 at the shaft end.

In this case, a pipe-shaped heat insulating layer is formed between the cooling liquid jet and the swirling flow, and the latent heat surface can be cooled without mixing the cooling liquid jet and the swirling flow liquid.
The cooling effect is improved.

When the present invention is applied to a motor of 500 KW-4 poles, heat generation of several Kcal / sec is generated. In the present invention, water is used as the cooling liquid, and the jet pressure of the water is 2 to 2.
At 3 kg / cm ² , the desired effect can be sufficiently obtained. A large effect can be obtained when the internal pressure of the evaporation / condensing chamber 2 is about 100 mmHg Abs.

As shown in the figure, a stator cooling jacket 9 is provided on a stator side casing before cooling liquid jet injection, and the cooling liquid is supplied to the stator cooling jacket 9.
By jetting the cooling liquid into the cooling liquid chamber 4 after passing through, the configuration of the cooling device can be relatively simplified, and the cooling effect can be improved.

If the structure of the cover surrounding the drain impeller 6 at the shaft end of the rotor shaft 1 is a spiral chamber like a casing of a known centrifugal pump, the drainage efficiency is increased.
Further, if a shallow spiral groove is provided on the cylindrical inner wall surface in the cooling liquid chamber 4 so as to obtain a desired swirling flow, a further excellent effect can be obtained.

The present invention can be applied to a motor having an output of about 150 KW or more to obtain excellent effects. For example, by adopting the configuration of the present invention with a motor size of 200 KW,
A liquid-cooled induction motor with an output of about 500 KW is obtained.

Further, when the present invention is applied to a vertical liquid-cooled induction motor, a thrust load is added to the bearing. However, since the size of the motor can be reduced, the bearing burden can be reduced and the bearing can be reduced in size. Thus, a four-pole high-speed induction motor, which could not be expected at high output, can be realized.

[0016]

According to the present invention, a rotor for an electric motor is provided.
1, a vacuum-sealed annular evaporation / condensation chamber 2 is provided inside 1,
A cooling liquid chamber 4 is provided inside the evaporation / condensing chamber 2 inside the rotor shaft.
And a drainage impeller for the liquid chamber 5 connected to the end of the cooling liquid chamber 4.
A liquid-cooled induction motor provided with a rotor shaft 7
Coolant 3 is continuously cooled by high-speed jet from the shaft end
4, the coolant 3 colliding with the other end of the coolant chamber 4 is distant.
It will be deflected to the side of the evaporation / condensation chamber 2 by the force of the heart to make it flow.
As a result , a small, high-output liquid-cooled induction motor can be obtained by simple means.

[Brief description of the drawings]

FIG. 1 is a vertical sectional side view showing a liquid-cooled induction motor according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional side view showing an enlarged upper part of FIG. 1;

FIG. 3 is an enlarged longitudinal side view showing a lower portion of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotor 2 Evaporation / condensing chamber 3 Coolant 4 Coolant chamber 5 Liquid chamber 6 Impeller for drainage 7 Rotor shaft 8 Stator 9 Stator cooling jacket 10 Injection port 11 Liquid supply pipe 12 Drainage hole 13 Drainage port 14 Cooling Impeller 15 Motor fixing member

Claims (1)

(57) [Claims] 1. A vacuum tight inside a rotor 1 of an electric motor.
A closed annular evaporation / condensation chamber 2 is provided.
A cooling liquid chamber 4 is provided inside the rotor shaft, and an end of the cooling liquid chamber 4 is provided.
Liquid cooling with drainage impeller 6 provided in liquid chamber 5 connected to section
A high-speed induction motor from the shaft end of the rotor shaft 7.
The cooling liquid 3 is continuously injected into the cooling liquid chamber 4 by
The coolant 3 colliding with the other end of the chamber 4 is evaporated and coagulated by centrifugal force.
Liquid cooling characterized by being deviated and flow toward the shrinking chamber 2
Type induction motor.