JPS5812550A - Rotary electric machine - Google Patents

Abstract

PURPOSE:To prevent deterioration of the insulation of a rotary electric machine by inserting an insulating member to the central part of an upper coil when two- layer randomly wound coil is inserted into a slot and urging the coil strand to both side walls, thereby reducing the temperature difference between upper and lower coils. CONSTITUTION:When two-layer randomly wound upper and lower coils 15 and 12 are inserted into a slot 10, an insulating member 17 is inserted into the central part between strands of the upper coil 15 to urge the strand 15a of the upper coil to the side surface of tees 18 at both sides of the slot. In this manner, the cooling of the coil 15 can be improved, thereby averaging the temperature distribution in the slot. Accordingly, the deterioration in the insulation can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotating coil in which the temperature difference between the upper and lower coils of a 11-12-layer irregularly wound coil is reduced.

The armature windings of rotating electric machines can be classified into those using randomly wound coils and those using pattern wound coils. Randomly wound coils are generally used for low voltage windings of 600V or less, while circularly wound coils are often used for higher voltage windings. Furthermore, armature windings often include two-layer windings in which two coils are inserted into one slot, and single-layer windings in which one coil is inserted in one slot, but #i2 is the subject of the present invention. In the case of stratified winding, the upper coil and the lower coil are generally separated and wrapped in insulating paper, and the lower coil is placed on the bottom side of the core's loft, and the upper coil is placed on the opening side. ◇ When we investigated the temperature rise during operation of the upper coil and lower coil, we found that the space factor for the coil slot and the space between the coils were It depends on the quality of the resin impregnation, but with an F11 insulated motor, 5 to 2D chi1! The temperature is different, and the upper coil is hotter. This phenomenon affects the deterioration of insulation and therefore the life of the motor, so the smaller the temperature difference, the better.

An object of the present invention is to improve the cooling structure of the upper coil, reduce the temperature difference between the upper and lower coils, prevent insulation deterioration, and provide a rotating electric machine with a long life.

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. FIG. 1 is an elevational view of the upper half of a completely enclosed fan-shaped squirrel cage induction motor.

The rotor core (2) with the squirrel cage winding (1) has an outer layer (3
) and are fitted onto a rotating shaft (4) and rotatably supported by a bearing (5). Denshinko volume! The stator core (7) with (6) is press-fitted into the stator frame (8). Bearing brackets (9), (9) fi are attached to both ends of the stator frame (8) and support the bearings (5), (5).

The stator core (7) has a plurality of slot portions shown in FIG. 2 on its inner periphery. In other words, the slot) (Into the bottom of 11, insert the randomly wound lower coil (I side) wrapped in the first insulating paper aυ, and on top of it, insert the third insulating paper 0 through the second insulating paper 03.
Insert the upper coil osu wrapped in 4, and insert the upper and lower coils (
Is', a side is wrapped together with a fourth insulating paper ae, and the upper part of the coil a is wrapped with a third and fourth insulating paper an,
Before wrapping with cLs, in advance, insert a plate-shaped insulating member (17) that widens towards the bottom of the slot into the strands (1) of the upper coil α1.
5a) and press the wire (15a) against the tooth α barrels on both sides. After that, third and fourth insulating paper i
Fold the upper ends of n and a* to wrap around the upper coil α1, insert the wedge (II) into the opening side of the slot) Q, and wrap the upper and lower coils Q.
e. Hold Q3. Then, a predetermined resin impregnation treatment is performed. (to) is the core part of the iron core.

Next, the effect will be explained.

During operation, both the upper and lower coils (LS, Q3) generate copper loss, and the temperature tends to rise.The heat generated in the lower coil a during operation is transferred to the core (1) on the bottom side of the slot and the teeth on both sides. The heat is transmitted to the α mallet part and dissipated over a wide area as before. Therefore, cooling is good. The heat generated in the upper coil is mainly dissipated to the teeth 08 on both sides of the slot. , dissipating heat to the core (1) via the lower coil (l) is not very desirable because the temperature of the lower coil a3 has risen considerably and the path is long.
Dissipating the heat of the upper coil via If' (11) is not very desirable since the thermal conductivity of 4I!■ is not good.

Here, when talking about the amount of heat transfer, generally Q is the amount of heat transfer, α is the heat transfer coefficient, A is the heat passing area, (1> −
If 11) is the temperature difference, the following equation holds true.

Q”('-A・(tx) −−−・−(1
01) As in this example, by pushing the insulating member αη into the center of the strand (15 m) of the upper coil a9,
(15a) Comrades and strands (15a) and insulating paper an, as
By improving the adhesion with the teeth On through the (
The heat transfer coefficient d in equation 101) is improved, and the amount of heat transfer is increased even though the heat passing area A is smaller than the lower coil α. Therefore, the temperature of the upper coil a decreases, and according to this embodiment, the temperature of the upper coil α9 has no variation compared to the temperature of the lower coil o3, and increases by only a few degrees.

Note that the present invention is not limited to the embodiment O described above and shown in the drawings, and may be applied to rotating electrical machines of other structures, such as a paper-proof type or a completely closed pipe ventilation type. Of course, it is possible to implement various modifications without changing the gist of the invention.

As explained above, according to the present invention, by inserting an insulating member into the center of the wire of the upper coil inside the slot and pressing it against the teeth on both sides of the wire, the cooling of the upper coil is improved. By reducing the temperature difference with the lower coil and making the temperature distribution uniform, the insulation life can be extended and a highly reliable rotating electric machine can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of the upper half of an embodiment of the rotating electrical machine of the present invention, and FIG. 2 is an enlarged sectional view showing the stator slot portion of the rotating electrical machine shown in gJ1. 7... Iron core 10... Slot 12...
- Lower coil b... Upper coil 15a... Element wire 17... Insulating member 18... Teeth
19...Kedge Agent Patent Attorney Inoue - Male

Claims (2)

[Claims] (1) In a rotating electric machine in which two-coil coils are inserted into multiple slots provided in the iron core and a wedge is inserted into the slot opening to hold down the coils, a strand of wire is inserted in the center of the strand of the upper coil inside the slot. A rotating electric machine characterized by inserting an insulating member that is pressed against the teeth on both sides. . (2) The rotating electrical machine according to claim 1, wherein the insulating member has a cross section that is a plate that widens toward the bottom of the slot.