JPH06245421A - Cooler for rotor of squirrel-cage induction machine - Google Patents

Abstract

PURPOSE:To increase the output of a squirrel-cage induction machine by providing air gaps between holes of a plurality of conductors, a pocket formed at a short-circuiting ring and radial holes at core retainers of both sides, an outer periphery of the core retainer, a bore of the ring. CONSTITUTION:When refrigerant W is poured from a pouring hole 1a of a shaft 1, it flows from a plurality of radial holes 5b through cutout grooves 5a of a core retainer 5, to a pocket 4b through a radial hole 4a formed at a short-circuiting ring 4 through an O-ring 6 of a metal and flows to the pocket 4b of the ring 4 through holes 3a of a plurality of conductors 3. It is passed through the hole 4a, the ring 6, the holes 5b to be collected to the grooves 5a of the retainer 5 and discharged externally from refrigerant discharge hole 1b of the shaft 1. Accordingly, when a squirrel-cage induction machine is operated with a load, Joule loss heat is dissipated to the conductors of the rotor and the ring, and iron loss heat is generated in the core, but externally dissipated via the refrigerant. As a result, heat exchanging efficiency is improved, the machine can be reduced in size and increased in output.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling device for a rotor of a basket type induction machine.

[0002]

2. Description of the Related Art A cross section of a rotor of a conventional liquid cooling basket type induction machine is shown in FIG. In FIG. 4, 1 is a hollow shaft, and 2 is a rotor iron core press-fitted into the shaft. The rotor iron core 2 is fixed by iron core retainers 5 from both sides. Further, all the conductors 3 are inserted into the plurality of slots of the rotor core, and the short-circuit rings 4 are welded to both ends of the conductors. The rotor is formed with the above configuration. Therefore, during the load operation, a part of the Joule's heat loss generated from the conductor and the short-circuit ring and the iron loss heat generated from the rotor core was released to the outside by the refrigerant body W injected into the hollow shaft.

[0003]

In the conventional basket type induction machine rotor, the heat generated from the conductor and the short-circuit ring and the heat generated from the rotor core are both transmitted from the core to the hollow shaft. However, since it is released to the outside by the refrigerant flowing inside the hollow shaft, the heat exchange efficiency is very poor, and there are problems in downsizing the cage induction machine and increasing the output. The present invention has been made to eliminate the above-mentioned drawbacks.

[0004]

The means is to provide holes 3a in a plurality of conductors 3. A plurality of pockets 4b are provided on the ring-shaped short-circuit ring 4 for welding both ends of the conductor. Radial holes 4a are provided in the axial direction from each pocket portion. Holes 5b are radially provided on the iron core retainers 5 on both sides of the cylinder so as to correspond to the radial holes 4a of the short-circuit ring. A gap G is provided between the outer diameter of the iron core retainer 5 and the inner diameter of the short-circuit ring 4. An O-ring 6 is provided at the connection between the short-circuit ring hole 4a and the iron core holding hole 5b. A notch groove 5a is provided on the circumference on the inner diameter side of the iron core holding hole 5b. The notch groove is provided in the press-fitting portion between the shaft 1 and the iron core retainer. The shaft 1 is provided with a coolant injection hole 1a and a discharge hole 1b from the shaft end to predetermined positions. A hole 1c and a hole 1a are provided in the outer diameter direction from the tip of each hole, and are aligned with the notch groove 5a of each iron core retainer. The present invention has the above configuration.

[0005]

When the cooling medium W is injected from the hole 1a, the shaft 1 passes through the notch groove 5a of the one iron core retainer 5 and passes through a plurality of radial holes 5b connected to the notch groove 5a. From the hole 5b, through the O-ring 6, through the hole 4a of the short-circuit ring, it flows into the pocket 4b. From each pocket portion, through the holes 3a of the plurality of conductors 3 mounted in that portion, flows into the pocket portion 4b of the other short-circuit ring 4, gathers in the notch portion 5a of the other iron core holder, and The heat generated during the load operation is dissipated to the outside through the hole 1b.

[0006]

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 of a cooling device portion of a rotor,
FIG. 2 is an exploded perspective view showing a partial cross section of the device component.
1 and 2, a shaft 1 of a rotor is provided with holes 1a and 1b from the shaft end to predetermined positions. The predetermined position is a position approximately in the center of the press-fitted portion of the cylindrical iron core retainer 5 with the rotor shaft. Holes 1c and 1d in the outer peripheral direction from the tip of the hole, respectively
To provide. A notch groove 5a is provided at the center of the press-fitted portion of the iron core retainer 5 at both ends of the rotor iron core 2 with the shaft 1. Hole 1a, hole
1b and the notch groove 5a of both iron core presser are matched.
A plurality of holes 5b are provided radially from the central portion of the notch groove 5a of both iron core retainers.

The ring-shaped short-circuit ring 4 is provided with the same number of holes 4a in the same direction as the radial holes 5b of the iron core retainer. The hole 4a
A groove with a predetermined width is provided in the circumferential direction at the tip of the. A conductor receiving hole 3a is provided in a side plate portion of the groove on the conductor 3 side. The groove is welded with a plurality of partition plates 4d to form a plurality of pockets.
Form 4b. The conductor 3 is inserted into the conductor receivers 3b of the short-circuiting rings on both sides of the conductor 3 and welded. Seal and weld the pocket with the pocket lid 4c. A gap G is formed between the short-circuit ring 4 and the iron core retainer 5. Metal O is used to connect the iron core retainer hole 5a and the short-circuit ring hole 4a.
The ring 6 is provided. During operation, the conductor expands axially due to thermal expansion. One embodiment of the present invention is configured as described above. It should be noted that heat-resistant and oil-resistant synthetic resin may be used instead of the metal O-ring.

Next, the operation will be described with reference to FIG. When the cooling medium W is injected from the injection hole 1a of the shaft 1, it passes through the notch groove 5a of the one iron core retainer 5 and has a plurality of radial holes.
Flow from 5b through the metal O-ring 6 through the radial holes 4a provided in the one short-circuit ring 4 to the pocket portion 4b. The other short-circuit ring 4 passes through the holes 3a of the conductors 3 from the pocket.
Flows into the pocket 4b of the. Then, they pass through the hole 4a, the metal O-ring 6 and the hole 5b, and are gathered in the notch groove 5a of the other iron core retainer 5 and are discharged to the outside from the coolant discharge hole 1b of the shaft 1.
Therefore, when the basket-type induction machine is operated under load, Joule loss heat is generated in the conductor and the short-circuit ring of the rotor, and iron loss heat is generated in the iron core, but since the refrigerant body passes through the above path, The heat generated by the conductor and the short-circuit ring is radiated by the refrigerant body passing through the passage hole and the iron loss heat is radiated to the outside by the refrigerant body via the iron core holding conductor and the shaft. In addition, cold air,
Cold liquid (water, oil) or cold gas is used.

[0009]

Since the present invention is constructed as described above, it has the following effects. The load heat generated in the rotor during load operation is discharged to the outside together with the medium by the refrigerant body, so that the heat exchange efficiency becomes very good, and the cage induction machine can be downsized. As a result, the output can be increased.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a cooling device portion of a rotor according to the present invention.

FIG. 2 is a detailed exploded perspective view showing a partial cross section of a component of the rotor of the present invention.

FIG. 3 is a perspective view of a refrigerant passage of the cooling device according to the present invention.

FIG. 4 is a cross-sectional view of a conventional rotor.

[Explanation of symbols] 1 axis 1a refrigerant injection hole 1b refrigerant medium discharge hole 1c hole 1d hole 2 rotor core 3 conductor 3a conductor hole 3b conductor receiving hole 4 short-circuit ring 4a hole 4b pocket part 4c pocket part lid 4d partition plate 5 Iron core retainer 5a Notch groove 5b Hole 6 Metal O-ring G Gap 7 Reinforcement ring 8 Plug A Refrigerant body injection direction B Refrigerant body discharge direction W Refrigerant body

Claims (1)

[Claims] 1. A rotor of a cage induction machine comprising a shaft (1), an iron core (2), a conductor (3), a short-circuit ring (4) and an iron core retainer (5), wherein a plurality of conductors (3) are provided. A hole (3a) is provided, a plurality of pockets (4b) are provided in a ring-shaped short-circuit ring (4) for welding both ends of the conductor, and the same number of radial holes as the number of pockets are provided axially from each pocket ( 4a) is provided, and holes (5b) are radially provided in the iron core retainer (5) on both sides of the cylindrical shape so as to correspond to the radial holes (4a) of the shorting ring, and the outer diameter of the iron retainer (5) and the shorting ring An air gap (G) is provided between the inner diameter and the O-ring (6) to connect the short-circuit ring hole (4a) and the iron core retainer hole (5b), and the inner core side of the iron retainer hole (5b) has a reverse concave shape. A cutout groove (5a) is provided, and the cutout groove is provided in the press-fitting portion of the shaft (1) and the iron core retainer (5), and the shaft (1) is provided with a coolant injection hole (1a) from the shaft end to a predetermined position, Discharge hole 1b) is further provided, and holes (1c) and holes (1a) are further provided from the tip of each hole in the outer diameter direction so as to match the notch groove (5a) of each iron core retainer. Cooling device for the rotor of a cage induction machine.