JPH05300686A - Magnetic wedge for slot - Google Patents

Abstract

PURPOSE:To obtain a magnetic wedge for a slot which has the desired magnetic characteristic by an easy manufacturing method. CONSTITUTION:A polyester resin fiber or resin thin band, an iron wire, an amorphous thin band, etc., are bound into a bundle. Then, epoxy resin is dropped on this bundle or this bundle is dipped in the epoxy resin to be impregnated with the epoxy resin. After that, the bundle is passed through a dice of a specified shape and then is heat-treated to harden the impregnated resin. Thus, a magnetic wedge is formed. By optimizing the quality of magnetic bodies such as the iron wire, the amorphous wire and the amorphous thin band and by optimizing the position of these magnetic bodies in a cross section of the wedge, the wedge is allowed to exhibit its abilities to the maximum when it is incorporated into an armature. Continuous supply sources 11-1, 11-2,..., 11-n of a non-magnetic fiber or thin band (non-magnetic roving) and continuous supply sources 21-1, 21-2,...21-m of a magnetic fine wire or thin band (magnetic roving) are prepared. When the magnetic roving is a thin band, only one supply source will do. All these supply sources are bound into a bundle and is led to an impregnation resin vessel 13 and then is passed through a dice 14 for extrusion and finally it is hardened by measured of a furnace 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic wedge mounted in an opening of an armature slot, and more particularly to a magnetic wedge for an armature slot which is a combination of an insulating material and a magnetic material.

[0002]

2. Description of the Related Art For the purpose of, for example, improving the efficiency and power factor of an electric motor, or reducing electromagnetic noise and electromagnetic vibration, it is common practice to insert a magnetic wedge into the opening of an armature slot. It is known that its purpose can be further divided into two types from the viewpoint of action.

That is, the first is to reduce the distortion of the magnetic flux in the air gap due to the difference in the magnetic resistance between the teeth of the stator core and the opening, and to expand the effective magnetic path area between the stator and the rotor. It aims to reduce resistance. Second, the magnetomotive force harmonics generated from the rotor and the permeance harmonics generated due to the difference in magnetic resistance between the rotor teeth and the slots are magnetically short-circuited by the magnetic wedge at the stator slot opening, Avoid interlinking with the winding to avoid harmonic iron loss that occurs in the stator core and harmonic copper loss that occurs in the stator winding. or,
Aims to reduce the loss, noise, and vibration that occur when harmonic magnetic flux flows into the rotor side by short-circuiting the harmonic magnetomotive force generated when operating with an inverter power supply containing distorted waves by a magnetic wedge. Is.

[0004]

As the magnetic wedge for the purpose of the first effect, the magnetic powder of iron powder which is easy to pass the magnetic flux of the power source frequency as shown in FIGS. 15 (a) and 15 (b) has been used as the magnetic wedge. To
Resin molded products have been widely used. It is easy to distribute the magnetic powder uniformly in the wedge cross section, but it is difficult to distribute it magnetically to a desired position. Further, it is difficult to form a desired cross-sectional shape, and a great deal of labor is required for cutting to obtain a desired shape by cutting.

Further, as the magnetic wedge for the purpose of the second action, conventionally, an amorphous thin ribbon having a high harmonic permeability as shown in FIG. 16 is adhered to a non-magnetic wedge. However, labor was required to bond the amorphous ribbon to the non-magnetic wedge, and the amorphous ribbon was damaged when it was inserted into the armature slot, and the mounted amorphous was peeled off. Furthermore, a magnetic wedge for simultaneously achieving both the first and second actions has never been realized. The present invention has been made in view of such circumstances, and an object thereof is to provide a magnetic wedge for a slot having desired magnetic characteristics by a simple manufacturing method.

[0006]

According to the present invention, a resin fiber or resin ribbon made of polyester and a bundle of iron wire, amorphous thin wire, amorphous ribbon, etc. are impregnated with an epoxy resin by dropping or dipping. Then, a dice having a predetermined shape is passed through, and the impregnating resin is cured by a heating process to form a magnetic wedge. By optimizing the material of the magnetic material such as iron wire, amorphous wire, amorphous ribbon, etc. and the arrangement of these in the wedge cross section, it is configured to maximize the performance when assembled in the armature. Is.

[0007]

The first purpose is to reduce the distortion of the magnetic flux in the air gap due to the difference in the magnetic resistance between the stator core teeth and the opening, and further to reduce the magnetic resistance between the stator and the rotor. The second is to avoid interfering with magnetomotive force harmonics and permeance harmonics generated from the rotor with the stator winding, and to generate harmonic iron loss inside the stator core and inside the stator winding. Avoid harmonic copper loss. Further, the harmonic magnetomotive force generated when operating with an inverter power supply containing a distorted wave is short-circuited by a magnetic wedge to reduce loss, noise and vibration generated when a harmonic magnetic flux flows into the rotor side.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, a plurality of nonmagnetic roving supply sources 11-1, 11-2, 11 capable of continuously supplying nonmagnetic fibers or ribbons (hereinafter referred to as nonmagnetic roving).
-3 ... 11-n and magnetic roving supply sources 21-1, 21-2, 21-3, 21-m capable of continuously supplying magnetic thin wires or magnetic ribbons (hereinafter referred to as magnetic rovings) are prepared. To do. The magnetic roving source may be one when the magnetic band is a thin band.

From each of the magnetic roving supply source and the non-magnetic roving supply source, rovings 12-1, 12-2, 12-3 ...
1, 22-2, 22-3, 22-m are drawn out, bundled and guided into the impregnating resin tank 13 to impregnate each roving with the resin. As a method of impregnating the resin, a method of impregnating the resin while dropping it into the roving in a bundle may be adopted.

The roving impregnated with the resin thus obtained is guided through a roller and drawn in a desired arrangement through a die 14 having a required wedge cross-sectional shape. When cured, a magnetic wedge for a slot in which a magnetic material is dispersed in a non-magnetic material is formed on the cross section.

A typical example of the cross-sectional shape of the magnetic wedge thus manufactured is shown in FIGS. Such a magnetic wedge has higher mechanical strength than a conventional one using iron powder, improves workability when incorporated in an armature, and is also suitable for mechanization of assembling work. Further, since the cross-sectional shape suitable for incorporating the armature can be obtained without cutting, the magnetic wedge itself can be easily manufactured.

FIG. 4 shows an example of a magnetic wedge cross section when an amorphous thin wire is used as the magnetic thin wire and FIG. 5 is a magnetic wedge cross section when an amorphous thin wire is used as the magnetic thin ribbon. As the magnetic material of the magnetic wedge, amorphous is used by bonding an amorphous thin ribbon to a non-magnetic wedge. This contributes to the improvement of the efficiency of the rotating machine, and by improving the efficiency of the motor by amorphously shorting the harmonics of the motor that is driven by the power source that contains a lot of harmonics in the power supply voltage such as the inverter. noise,
It has been found to help reduce vibration. According to the present invention,
Since the work of adhering the amorphous ribbon to the non-magnetic wedge is unnecessary, it becomes possible to easily manufacture it, and it is possible to eliminate the conventional problems such as peeling of the adhered portion.

By adopting the above-described manufacturing method shown in FIG. 1, it is extremely easy to obtain the optimum configuration for the performance aiming at the arrangement of the magnetic material portion in the magnetic wedge cross section. The embodiment will be described with reference to FIGS. 6 to 13.

FIG. 6 shows a non-magnetic roving 31 at the center.
FIG. 6 is a cross-sectional view of a magnetic wedge for slots obtained by arranging the magnetic rovings 21 in a concentrated arrangement on the iron core tooth side and on the outer edge of the air gap surface between the stator and the rotor. When this magnetic wedge is attached to the opening of the slot 2 in which the coil 1 is housed as shown in FIG. 7, the main magnetic flux can be passed as shown by the solid line arrow in the figure to reduce the air gap surface harmonic magnetic flux. The leakage magnetic flux indicated by the broken line arrow in the drawing that tries to pass through the wedge 3 can be suppressed to a sufficiently small value by the non-magnetic roving portion 31 in the wedge, and the adverse effect of an increase in leakage magnetic flux due to the magnetic wedge can be minimized. I can do things.

FIG. 8 and FIG. 9 are wedge cross-sectional views of an embodiment using a material having a high harmonic permeability and a low saturation magnetic flux density (for example, amorphous) as the magnetic roving. FIG. 8 shows an example in which an amorphous thin wire 41 is used for magnetic roving, and FIG. 9 shows an amorphous ribbon 42. This will be described below with reference to FIG.

The magnetic wedge 4 shown in FIG. 8 is attached to the opening of the stator slot 7 in which the coil 5 is housed.
It is 2. As shown in FIG. 8, when the amorphous thin wire 41 used as the magnetic roving is installed in the opening of the slot 7, it is parallel to the gap between the stator and the rotor so as to magnetically connect the stator teeth 6 and 6 '. Are lined up. Therefore, the magnetomotive force harmonic magnetic flux and the permeance harmonic magnetic flux generated from the rotor pass through the amorphous thin wire 41 as shown by the one-dot chain line arrow in the figure, and flow into the coil 5 without interlinking with the harmonics generated in the stator core. Corrugated iron loss and harmonic copper loss generated in the coil 5 are reduced.

Further, in the case of an electric motor operated by an inverter power supply containing many harmonics in the power supply voltage, the coil 5 shown in FIG.
When there is no magnetic wedge, the harmonic magnetomotive force creates a harmonic magnetic flux that reaches the rotor as shown by the solid line arrow in the figure, which causes an increase in harmonic loss in the rotor, electromagnetic noise, and electromagnetic vibration. Was there. By installing a magnetic wedge 4 as shown in FIG. 8 in the stator slot opening, the harmonic magnetic flux passes through the amorphous thin wire 41 as shown by the one-dot chain line arrow in the figure and does not reach the rotor. It will contribute to the reduction of loss, noise and vibration.

Further, the same effect can be obtained by using an amorphous ribbon as shown in FIG. Furthermore, FIG. 6 and FIG.
As the magnetic wedge having the features of the magnetic wedge shown in FIG. 12, it is possible to easily manufacture a magnetic wedge having a cross-sectional structure in which both are combined as shown in FIG.

That is, magnetic rovings 21 made of, for example, iron wire, through which the fundamental wave magnetic flux easily passes, are concentratedly arranged on the outer peripheral portion on the iron core tooth side when the magnetic wedge is mounted and on the side of the gap between the stator and the rotor. Further, in order to magnetically short-circuit the teeth of the stator, for example, amorphous magnetic rovings 41, which facilitate passage of harmonic magnetic flux, are arranged in parallel with the gap between the stator and the rotor, and the non-magnetic rovings 31 are arranged in other portions. An excellent magnetic wedge for slots can be obtained by arranging.

This magnetic wedge has the advantages of the magnetic wedge shown in FIGS. 6 and 8 and is mounted in the armature slot opening, so that the main magnetic flux is deteriorated in characteristics due to an increase in leakage flux. Minimize and reduce the harmonic flux in the air gap between the stator and rotor. Further, the harmonic flux generated by the rotor or the harmonic flux generated by the inverter operation is short-circuited with a magnetic wedge, and the adverse effect thereof is not given to the main magnetic circuit and the coil, improving the efficiency of electric equipment. It greatly contributes to the reduction of noise, noise and vibration.

Further, as shown in FIG. 13, in the cross section of the magnetic wedge, it is possible to easily manufacture the wedge surface which is covered with the non-magnetic roving 31 without fail. In general, the material of the magnetic roving 21 is often a metal, is a conductive material, and is likely to rust. Therefore, the surface of the magnetic wedge of the magnetic wedge is covered with a thin insulator that does not impair its characteristics and a non-magnetic material having strong corrosion resistance, so that the insulating property and corrosion resistance of the magnetic wedge can be improved.

Further, in the cross section of the magnetic wedge as shown in FIG. 14, even if a recess is provided on the nonmagnetic roving portion, especially on the coil side of the central portion, the characteristic as the magnetic wedge is not impaired and the coil is not damaged. Can be stored in the slot by a corresponding amount, and hardening such as easy insertion of a magnetic wedge can be obtained. By adopting such a method, it is easy to continuously form a magnetic wedge having excellent magnetic characteristics and stable magnetic characteristics, which is suitable for mass production at low cost.

[0023]

As described above, according to the present invention, it is possible to provide a magnetic wedge for a slot which is excellent in magnetic properties, insulating properties, corrosion resistance and high productivity.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of a manufacturing process of a magnetic wedge showing an embodiment of the present invention,

FIG. 2 is a sectional view of a magnetic wedge using a magnetic thin wire according to the first embodiment of the present invention,

3 is a cross-sectional view of the magnetic wedge of FIG.

FIG. 4 is a sectional view of a magnetic wedge using an amorphous thin wire according to a second embodiment of the present invention.

5 is a cross-sectional view of the magnetic wedge of FIG. 4,

FIG. 6 is a sectional view of a magnetic wedge showing a third embodiment of the present invention,

7 is a conceptual diagram showing a magnetic flux flow when the magnetic wedge of FIG. 6 is attached to a slot,

FIG. 8 is a sectional view of a magnetic wedge using an amorphous thin wire according to a fourth embodiment of the present invention.

FIG. 9 is a sectional view of a magnetic wedge using an amorphous ribbon according to a fourth embodiment of the present invention,

FIG. 10 is a conceptual diagram showing the flow of harmonic magnetic flux due to the rotor when the magnetic wedge of the fourth embodiment is mounted in the slot.

FIG. 11 is a conceptual diagram showing the flow of harmonic magnetic flux due to the stator harmonic magnetic force when the magnetic wedge of the fourth embodiment is attached to the slot.

FIG. 12 is a cross-sectional view of a magnetic wedge showing a fifth embodiment of the present invention,

FIG. 13 is a sectional view of a magnetic wedge showing a sixth embodiment of the present invention,

FIG. 14 is a sectional view of a magnetic wedge showing an embodiment of the seventh aspect of the present invention;

15 (a) and 15 (b) are perspective views of a conventional magnetic wedge using magnetic powder,

FIG. 16 is a perspective view of a conventional magnetic wedge using an amorphous ribbon.

[Explanation of symbols]

3, 4 ... Magnetic wedge, 8 ... Rotor, 60 ... Stator, 2
2 ... Magnetic roving 11 ... Non-magnetic roving, 53 ... Amorphous ribbon.

Claims (7)

[Claims] 1. A non-magnetic fiber or fiber is formed by drawing a plurality of non-magnetic fibers or non-magnetic ribbons and magnetic fine wires or magnetic ribbons in parallel and impregnating them with resin and drawing them through a desired wedge cross-section shape die. A magnetic wedge for slots, characterized in that magnetic thin wires or magnetic ribbons are dispersed in the ribbon. 2. The magnetic wedge for slots according to claim 1, wherein an amorphous thin wire or an amorphous thin ribbon is used as the magnetic thin wire or the magnetic thin ribbon. 3. The magnetic wire for slots according to claim 1, wherein a large amount of magnetic thin wires or magnetic ribbons are dispersed in the iron core tooth portion of the wedge cross section inserted in the slot and the portion near the gap surface between the stator and the rotor. wedge. 4. The magnetic wedge for a slot according to claim 2, wherein an amorphous thin wire or an amorphous ribbon is arranged in a portion of the wedge cross section inserted into the slot, which is substantially parallel to an air gap surface between the stator and the rotor. 5. In the wedge cross section, a large amount of magnetic thin wires or magnetic ribbons are dispersed near the core tooth and the void surface between the stator and the rotor, and the amorphous thin wire or the amorphous wire is substantially parallel to the void surface. The magnetic wedge for slots according to claim 1, wherein a ribbon is arranged. 6. The magnetic wedge for slots according to claim 1, wherein a non-magnetic fiber or a non-magnetic ribbon is arranged around the wedge cross section and no magnetic material is present on the wedge surface other than the cut surface. 7. The magnetic wedge for a slot according to claim 1, wherein in the wedge cross section, a recess is provided on the gap surface between the stator and the rotor and on the reflection side.