JPH0591685A - Stator insulating coil - Google Patents

Abstract

PURPOSE:To provide a stator insulating coil in which dielectric strength is prevented from deteriorating by forming an insulation layer smoothly even if the molding pressure is imbalanced at the border of the linear part of the coil and the outer slot part 6 during insulation layer forming process of the insulating coil thereby forming a uniform insulation layer which is not damaged by a molding jig. CONSTITUTION:In an insulating coil where an insulation layer 3 is formed around a conductor 2 through vacuum pressure impregnation or prepreg insulation system, a strip mica tape 13 is applied on the outer periphery of the insulation layer 3 at the border of the linear part 5 and the slot outer part 6 of the coil.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stator insulated coil of a generator or the like.

[0002]

2. Description of the Related Art As a method of forming an insulating layer of a stator insulating coil, as shown in FIGS. 3 and 4, a mica tape is wound around a conductor 2 in which wires 1 are bundled to form an insulating layer 3. After forming and injecting the stator insulating coil 4 after winding the mica tape into the impregnation tank, pressurizing to impregnate the mica tape of the insulating layer 3 with the insulating resin, and further heat-molding vacuum pressure impregnation insulation There is a method and a prepreg insulation method in which a stator insulating coil 4 after winding a mica tape containing an insulating resin in advance around a conductor is formed by heating. Further, in recent years, the mica tape used here is mainly a laminated mica tape. Since the laminated mica tape is manufactured by paper-making minute scales obtained by crushing mica pieces, the mica distribution is uniform and the insulation performance after heat molding is excellent.

The stator insulating coil 4 is composed of a straight portion 5 and a slot outer portion 6, and the straight portion 5 is a straight portion obtained by extending a predetermined length to the length of the iron core 7 so as to be housed in the slot 8 of the iron core 7. The slot outer portion 6 is a curved portion formed from the end of the straight portion 5 to the end portion 9, the R portion 10, and the lead-out portion 11 according to an involute curve.

In the process of heat-molding the stator insulating ring 4, both the vacuum pressure impregnation insulating method and the prepreg insulating method, the insulating layer 3 of the insulating layer 3 is formed so as to have a predetermined sectional shape. A method in which a steel plate or shaped steel (hereinafter referred to as "molding jig 12") is applied to the surface, the heat-shrinkable tape is wound from above and heated, and pressure is applied by the storage force of the heat-shrinkable tape, or the above-mentioned molding Apply the jig 12 and heat with a heat press to apply pressure simultaneously with the insulation layer 3.
Is being heat molded. However, in the above heat molding method, the molding jigs 12 applied to the four surfaces are provided for the straight line portion 5 and the slot outer portion 6 in accordance with the shape of the stator insulating coil 4 from the viewpoint of economical efficiency and work efficiency. It was manufactured separately and used.

[0005]

In the above prior art, the molding pressure at the boundary between the linear portion 5 of the stator insulating coil 4 and the outside 6 of the slot is not uniform at the time of manufacturing, and the straight portion 5 side and the slot are not formed. In many cases, a difference in molding pressure occurs between the outer side 6 side. The reason for this is that it is difficult to wind the mica tape uniformly because the outside 6 of the slot has a curved shape compared to the straight portion 5, and the insulating layer 3 does not become smooth at the end of winding the mica tape, so that the molding cure is difficult. Forming jig so that the contact of the tool 12 becomes unstable, and the pressure is evenly distributed in the straight line portion 5.
It is easy to apply pressure to 12, but outside the slot 6
Since it is curved, the molding jig has an even distribution.
It is difficult to apply pressure to 12.

Due to the molding pressure difference caused by the above reasons, the linear jig 5 and the molding jig 12 of the slot outer part 6 are overlapped, and after the thermoforming, the linear part 5 of the stator insulating ring 4 and the slot external part 6 are formed. There was a case in which a dent was formed in the insulating layer 3 on the boundary part of. At the end of the molding jig 12 in the hollow portion, the insulating layer 3 was partially cut or the thickness of the insulating layer 3 was reduced, so that the dielectric strength was lowered.

The present invention has been made in view of the above-mentioned drawbacks of the prior art. Even when the molding pressures on the linear portion of the coil and the outside of the slot are unbalanced, a molding jig having an insulating layer formed smoothly is provided. It is an object of the present invention to provide a stator-insulated wire loop that is not damaged at the end of the stator and has no decrease in dielectric strength.

[0008]

In order to achieve the above object, the stator insulating coil of the present invention is a stator insulating coil in which a conductive mica tape is wound around a conductor and heat-molded to form an insulating layer. A peeling mica tape layer is provided on the outer periphery of the boundary portion between the linear portion of the wire ring and the insulating layer located outside the stator slot when housed.

[0009]

According to the stator insulation coil of the present invention, the pressure is locally applied due to an unbalanced molding pressure at the boundary between the linear portion of the stator insulation coil and the outside of the slot, or a one-side contact of the molding jig. Even if concentrated, the peeled mica tape wound around the outer periphery of the insulating layer has excellent mechanical strength, so the surface is not damaged and the insulating performance is excellent, so the insulating layer of the laminated mica tape can be protected. .

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to an embodiment shown in FIG.

In the stator insulating coil ring 4 of the present invention, the conductor 2 is wrapped with a plurality of mica tapes, and the outermost layer of the insulating layer 3 is wound with a mica tape. To leave. Next, a stripped mica tape is wound around the boundary portion to form a stripped mica tape layer 13. The stator insulating coil 4 having the outermost layer of the insulating layer 3 thus formed is subjected to vacuum pressure impregnation and heat molding to form a strong insulating layer 3. In addition, the electric field relaxation process of the straight part and the end part is performed by a conventional process suitable for the operating voltage of the rotating electric machine. Peeled mica tape is a sheet made by pasting a specified number of peeled mica pieces into a tape shape.The peeled mica tape itself has high mechanical strength. After the resin impregnation treatment, it is not easily damaged by an external force even if it is wet with the insulating resin until it is cured by heating. Therefore, even if the molding pressures of the straight portion 5 and the slot outer portion 6 become unbalanced, the insulating layer 3 on the boundary portion between the straight portion 5 of the stator insulating coil 4 and the slot outer portion 6 and the slot outer portion 6 is shaped. Since the insulating layer 3 can be smoothly molded without being partially cut or thinned at the end of the jig 12, the dielectric strength does not decrease.

Further, since the range of the stripped mica tape layer 13 is set to the boundary portion between the straight line portion 5 and the outside 6 of the slot, the economical amount of the stripped mica tape, which is more expensive than the assembled mica tape, is used as a minimum amount. This is to keep it. next,
Another embodiment will be described with reference to FIG.

In the stator insulating coil ring 4, a conductor 2 is wrapped with a laminated mica tape a plurality of times, and the outermost layer of the insulating layer 3 is covered with a straight line portion 5.
It is formed by winding a laminated mica tape without leaving the boundary between the slot 6 and the outside 6 of the slot. Next, the peeling mica tape 1 is applied only to the boundary between the linear portion 5 on the outer periphery of the insulating layer 3 and the slot outer portion 6.
The mica tape layer 13 which is wound and peeled off is formed. The stator insulating coil 4 having the insulating layer 3 thus formed is subjected to vacuum pressure impregnation and heat molding to form a strong insulating layer 3.

Also according to the above structure, since the peeling mica tape having high mechanical strength is wound around the boundary between the straight line portion 5 and the slot outer portion 6, the molding pressures of the straight line portion 5 and the slot outer portion 6 become unbalanced. However, since the insulating layer 3 is not partially cut at the end of the molding jig 12 and the thickness is not thinned, the insulating layer 3 can be molded smoothly, so that the dielectric strength does not decrease.

Further, since the peeling mica tape is wound around the boundary portion between the linear portion 5 of the insulating layer 3 and the outside 6 of the slot, the insulating thickness becomes thicker by that amount. However, compared with the embodiment shown in FIG. In that case, the time for interrupting the winding in the middle and performing the terminal treatment is not necessary, and since the laminated mica tape can be continuously wound for the outermost layer, the work time for winding the mica tape on the insulating layer 3 can be increased. Can be shortened.

In the above-mentioned structure, the laminated mica tape and the peeled mica tape to be used are made into a prepreg laminated mica tape and a prepreg peeled mica tape which contain insulating resin in advance. Also in the configuration of the stator insulating coil 4, the same effect can be obtained by winding the peeling mica tape having high mechanical strength around the boundary between the straight portion 5 and the outside 6 of the slot.

[0017]

As described above, according to the present invention, the peeled mica tape wound around the boundary between the linear portion on the outer periphery of the insulating layer of the coil and the outside of the slot has a mechanical strength superior to that of the laminated mice tape. The surface is not easily damaged by an external force, and even if the molding pressure becomes unbalanced at the boundary between the straight line portion and the outside of the slot, the insulating layer 3 is neither partially cut nor thinned. Can be molded smoothly,
It is possible to prevent a decrease in dielectric strength.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view of essential parts showing another embodiment of the present invention.

FIG. 3 is an explanatory view of a stator insulated coil.

FIG. 4 is a vertical cross-sectional view of the stator insulating coil of FIG.

FIG. 5 is a cross-sectional view of a main part of an insulated wire wheel showing a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Elemental wire 2 ... Conductor 3 ... Insulating layer 4 ... Stator insulating wire ring 5 ... Straight part 6 ... Slot outside 7 ... Iron core 8 ... Slot 9 ... End part 10 ... R part 11 ... Exit part 12 ... Molding jig 13 … Peeled mica tape layer

Claims (1)

[Claims] 1. A stator insulating coil formed by winding a laminated mica tape around a conductor and performing heat molding to form an insulating layer, wherein a boundary between the linear portion of the coil and the insulating layer located outside the stator slot when housed. A stator insulating coil having a peeled mica tape layer provided on the outer periphery of the portion.