JPH06284620A - Insulation coil for electric rotating machine - Google Patents

Abstract

PURPOSE:To provide an insulation coil in which creeping is retarded under high temperature at the intersection of wires fitted in the different slots of an electric rotating machine at the coil end part thereof. CONSTITUTION:In an insulation coil where an insulated wire 1 comprising a conductor 3 is fitted in a core slot part, a stress relaxing part (2) is provided at a coil end part where the wire 1 projects from the core slot part and intersects a wire 1 projecting from a different core slot part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulating coil for a rotary electric machine.

[0002]

2. Description of the Related Art Conventionally, insulating coils used in rotating electric machines are
For example, in the case of a low-voltage rotating electric machine, an enamel wire is wound to form an insulating coil, and in the case of a high-voltage rotating electric machine, several strands are bundled to form a coil conductor, and the coil conductor is formed on the outer periphery of the wire. Epoxy mica insulation is processed into an insulation coil.
However, in the case of an insulation coil in which the rotating electric machine itself is immersed in water, such as an underwater motor, and the insulation coil is also immersed in water, an electric wire insulated with polyethylene with good water resistance is wound around the slot of the iron core. I have something to do.

[0003]

In the insulated coil used in such a method, in the coil end portion outside the iron core,
The electric wires wound in the same slot are in linear contact with each other, but the electric wires wound in different slots are in cross contact with each other, so that they are in point contact. Polyethylene is a material that does not have very good heat resistance, so when force is applied to one point for a long time at high temperature,
Creep occurs at that part and the insulation thickness becomes thin. For this reason, in an actual insulated coil using a polyethylene electric wire, it has always been used under conditions where the temperature rise due to operation is suppressed as low as possible and creep does not occur.

An object of the present invention is to provide a coil end portion of an insulated electric wire wound around a slot portion of an iron core, and a portion of the coil end portion of the insulated electric wire, which crosses the electric wire wound around a different slot and makes point contact, even at a relatively high temperature. The purpose is to obtain an insulated coil that is resistant to creep.

[0005]

DISCLOSURE OF THE INVENTION The present invention relates to an insulated coil for a rotating electric machine, comprising an insulated electric wire in which a conductor is coated with an insulating material and wound around a slot portion of an iron core, wherein the electric wire comes out of the iron core slot portion. It is characterized in that a stress relaxation portion is provided at a portion of the end portion which intersects and comes into contact with an electric wire wound in a different slot. Due to this stress relaxation portion, the insulation thickness of the electric wire does not become thin even if the insulating coil is operated at a relatively high temperature for a long period of time, so that a sufficient operating life can be expected.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an insulating coil for a rotating electric machine according to the present invention will be described below with reference to the drawings. FIG. 3 is a sectional view of a polyethylene electric wire 1 according to an embodiment of the present invention. A polyethylene layer 4 is applied to the outer periphery of the conductor 3, and a protective sheath 5 is coated on the outer periphery of the conductor 3 to increase the mechanical strength.

FIG. 4 is a sectional view of an insulating coil 7 formed by winding the polyethylene electric wire 1 around a slot 8 of an iron core 6, and FIG. 5 is a perspective view of a coil end portion of the insulating coil 7 outside the iron core. . At the coil end portion of the insulating coil 7, the electric wires wound in the same slot make a linear contact, but the electric wires wound in different slots intersect and make a point contact.

FIG. 1 is an enlarged view of a coil end portion of an insulated coil of a rotary electric machine according to an embodiment of the present invention, in which the above intersection is enlarged. A stress relaxation portion is provided at the intersection of the electric wires 1 to relax the stress applied to the polyethylene layer. In this embodiment, as the stress relaxation portion, the insulating spacer 2 shown in FIG. 2 is inserted at the crossing portion, but it is preferable that the shape thereof is processed according to the shape of the electric wire so that the electric wire comes into contact with as wide an area as possible. In the example performed here, after inserting the insulating spacer at the crossing portion, the coil end portion was tightly bound by the insulating binding to fix the electric wire and the insulating spacer. You may make it adhere | attach with an adhesive agent.

Next, the operation of this embodiment will be described. In the insulated coil formed as described above, at the coil end portion where the electric wire extends from the iron core slot portion, the electric wire accommodated in the same slot and the electric wire linearly contact, but the electric wire accommodated in a different slot is different from the electric wire accommodated in the different slot. Cross and touch at one point. Therefore, the stress acting on the latter contact portion is extremely large as compared with the contact portion of the electric wires housed in the same slot. Therefore, in this embodiment, in order to relieve the stress, an insulating spacer is inserted at the intersection as a stress relieving portion. Since the spacer is processed according to the shape of the intersecting portion, the electric wire and the spacer are in surface contact with each other. Therefore, the stress applied to the intersection of the electric wires is dispersed by the stress relaxation section and becomes small. Therefore, even if the insulated coil of this embodiment is operated at a relatively high temperature for a long period of time, the polyethylene layer does not creep at the intersection and the insulation thickness does not become thin.

FIG. 6 shows the relationship between the amount of deformation due to creep and the temperature when a constant load is applied to polyethylene, and the amount of deformation increases as the temperature rises. For this reason, in the insulated coil using the polyethylene wire, the device design has been performed so that the operating temperature is as low as possible. However, according to the present embodiment, since the stress at the wire crossing portion can be suppressed to a low level, it is comparatively possible. It became possible to operate at high temperature.

In the above embodiment, as the stress relaxation layer,
An insulating spacer processed according to the shape of the intersection was used, but the processing is relatively difficult. Therefore, as another example, as the stress relaxation portion, the stress relaxation portion may be formed by filling the crossing portion of the electric wire with a synthetic resin and curing it. In this case, the stress relaxation portion may be formed according to the shape of the wire crossing portion. It is not necessary to process the relaxation portion, and the work is extremely easy.

[0012]

As described above, according to the insulating coil of the rotating electric machine of the present invention, (1) stress can be relieved at the wire crossing portion of the coil end portion, so that the insulation coating can be maintained even after a long period of operation. There is almost no deformation and a long life can be expected. (2) Since the operating temperature can be designed to be higher than in the conventional case, the device can be downsized. (3) The stress relaxation portion formed at the electric wire crossing portion strengthens the fixation of the electric wires. For this reason, the abrasion due to vibration and rubbing between the electric wires is reduced, and the life of the insulation can be expected to be extended.

[Brief description of drawings]

FIG. 1 is an enlarged view showing an insulating coil of a rotary electric machine according to an embodiment of the present invention.

FIG. 2 is a diagram showing an insulating spacer used in an embodiment of the present invention.

FIG. 3 is a cross-sectional view of a polyethylene electric wire forming an insulating coil of a rotating electric machine.

FIG. 4 is a cross-sectional view of an insulated coil wound around a slot portion of an iron core.

FIG. 5 is a perspective view of a coil end portion of an insulating coil.

FIG. 6 is a graph showing the relationship between the amount of deformation of polyethylene caused by creep under a constant load and the temperature.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Polyethylene electric wire 2 ... Spacer 3 ... Conductor 4 ... Polyethylene layer 5 ... Protective sheath 6 ... Iron core 7 ... Insulating coil 8 ... Slot part 9 ... Electric wire crossing part

Claims (3)

[Claims] 1. An insulated coil for a rotating electric machine, comprising an insulated electric wire in which a conductor is coated with an insulating material, wound around a slot portion of an iron core, wherein the electric wire is a coil end portion extending from the slot portion of the iron core. An insulating coil for a rotating electric machine, wherein a stress relaxation portion is provided at a portion where and intersect with each other. 2. The insulating coil for a rotating electric machine according to claim 1, wherein the stress relaxation portion is made of an insulating spacer. 3. The insulated coil for a rotary electric machine according to claim 1, wherein the stress relaxation portion is formed by filling a synthetic resin.