JPS62285640A - Insulation treatment of coil end connection of rotary electric machine - Google Patents

Abstract

PURPOSE:To improve workability and insulating properties by applying an insulating semifluid substance around the connecting section of a coil end for a rotary electric machine and covering the connecting section with a heat- shrinkable insulating cap. CONSTITUTION:Half-turn coils l, 2 are housed in a slot in a core 3, and the coil ends of the coils 1, 2 are connected electrically by using a connecting copper band 4. A gel-like semifluid insulating substance 8 is applied around a connecting section 5 by using a spatula, etc. A heat-shrinkable insulating cap 6 previously manufactured so as to be conformed to the shape of the connecting section 5 is mounted before a film completely cures, and the hot air of a drier, etc., is struck and the film is thermally shrunk. Accordingly, the sealing performance of the connecting section of the coil ends is improved while the workability of insulating treatment is also enhanced.

Description

[Detailed Description of the Invention] 3. Detailed Description of the Invention [Object of the Invention] (Industrial Application Field) The present invention is a rotary i! The present invention relates to a method for insulating the connection portion of a stator coil end used in a machine.

(Prior Art) Generally, a stator coil for a large-capacity rotating electric machine is manufactured in the shape of a half-turn coil, and then placed in a slot.

After this, the coil ends are connected to form a one-turn coil.

For example, as shown in FIG.
.

A rotary machine can be used in a wide variety of environments, and the coil end connections must also have sufficient dielectric strength. In particular, consideration must be given to moisture-proofing, waterproofing, and preventing the adhesion of conductive foreign matter to the coil end connection portion.

In addition, as devices become smaller, the spacing between adjacent coils has become narrower, so care must be taken to avoid flooding between different-phase coils during withstand voltage tests.

Conventionally, the method described below has been used to insulate the coil end connection portion 5. (For example, JP-A No. 5
9-86448) ■ A method of wrapping insulating tape such as mica tape a predetermined number of times while applying insulating varnish. (hereinafter referred to as the taping method) ■ Method 6 in which the coil end connection portion 5 is covered with a box-shaped insulating cap 7, and the gap inside this is filled with room temperature curing type synthetic resin 9 (hereinafter referred to as the resin filling method) ) Of these, the taping method is less workable and economical, so
Recently, the resin filling method has become mainstream.

[Problems to be Solved by the Invention] Although the resin filling method can shorten the working time compared to the taping method, the filling work can be very difficult depending on the working position. For this reason, there is a major drawback in that cracks and voids occur in the resin-filled portion, significantly reducing the dielectric strength of the portion.

Further, the insulation treatment work for the connection portions largely depends on the skill level of the worker, and it is difficult to obtain uniform insulation performance.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and provide a method for insulating a coil end connection portion of a rotating electrical machine with good workability and insulation performance.

[Structure of the invention]

(Means for solving the problem) After applying an insulating material 8 having theory 1jJ properties around the coil end connection part 5 of the rotating electrical machine, a heat-shrinkable insulating cap 6 is placed to cover it. .

Next, the insulating cap 6 is thermally shrunk by applying heat from a hair dryer or the like to form connection insulation.

(Function) Since the semi-fluid substance 8 is fluid, the insulating cap 6
The gap between the coil end connection part 5 and the insulating cap 6 is completely filled by thermally shrinking the coil end connection part 5 and the insulation cap 6.

(Example) An example using the present invention will be described below.

FIG. 1 shows a coil end connection portion 5 of a rotating electrical machine that has been insulated according to the present invention.

After the half-turn coils 1 and 2 are housed in the slots of the iron core 3, the coil ends of the coils 1 and 2 are electrically connected using a connecting copper band 4.

After this, a gel-like semi-fluid, insulating substance 8 (for example, Toshiba Silicone Co., Ltd. trade name RTV-388) is applied around the connection part 5 using a spatula or the like. 6 The coating film is thick. The electrical properties will improve as the coating increases, but in reality, it is only necessary to apply enough coating to fill the voids.Next, before the coating film is completely cured, make it in advance to match the shape of the connection part 5. Attach the heat-shrinkable insulating cap 6 and heat-shrink it by applying hot air from a hair dryer or the like.

In this example, the insulating cap is made heat-shrinkable.

By imparting semi-fluidity to the inner filling material.

Insulation treatment can be completed easily. especially.

The opening of the insulating cap is completely sealed by the filling material, which is highly effective.

In order to confirm the effectiveness of the seal of this example, a low voltage electrode was provided on the insulating cap portion 6, and the insulation resistance in water was measured.

As a result, the insulation resistance did not decrease after being immersed in water for one week.
It was found that this example had sufficient sealing performance.

〔Effect of the invention〕

As described above, according to the present invention, the sealing performance of the coil end connection portion is improved, and at the same time, the workability of insulation treatment is also improved.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a rotating electric machine coil end connection part made by the method of the present invention, and FIG. 2 is a sectional view showing a connection part made by a conventional method. 1.2... Half-turn coil 3"°° Iron core 4...
Connection copper band 6...Heat-shrinkable insulation cap 8
...The theory of Hiko's material agent Patent attorney Nori Chika Yudo Hirofumi Mitsumata

Claims (1)

[Claims] A rotating electric machine characterized in that an insulating semi-fluid substance is applied around the connection part of a coil end of the rotating electric machine, a heat-shrinkable insulating cap is placed over the substance, and the insulating cap is heated and shrunk. Insulation treatment method for coil end connections.