JPH09219940A - Small induction motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the torque characteristics of a small motor by providing a projection, whose tip part has the specified width with respect to a yoke part at the side surface of an insulating body to the side of the outer surface of the yoke part. SOLUTION: For a stator 1, a winding 7, wherein a yoke part 6 is wound in a toroidal shape for each slot 4 through an insulating body 5 attached to a stator core 2 having many slots 4 separately adjusted by gear teeth at the inner surface, is wound. The stator 1 is molded with premixed resin as a unitary body. A rotor 11 is supported rotatably by ball bearings 14 and 15 supported on end brackets 12 and 13. In the insulating body 5, a projection 8, whose width size L3 of the tip part is set at less than 1/2 of the width L2 of the yoke part, is provided. Thus, the occurrence of collapse of the winding at the time of wire winding is prevented. In this way, the collapse of the winding can be prevented without applying any restriction on the wire winding work.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small induction motor.

[0002]

2. Description of the Related Art Conventionally, a stator of a small-sized induction motor is usually formed by winding a plurality of teeth in a slot formed in an inner circumference of a stator core and extending from slot to slot. The coil end portion was in a state of protruding from both end faces of the stator core, and the coil end portion was added, and the coil end portion as a whole had a considerably large axial dimension. On the other hand, as motors have become smaller and lighter in recent years, there has been an increasing demand for thinner ones. A method is being used to make it thinner. However, the toroidal winding method has the drawback of poor characteristics. That is, in the case where the toroidal winding is provided for each slot, the adjacent winding, that is, the winding of each slot portion cannot be wound at the same time, and the winding is performed first for each slot because of the winding. The wound winding will collapse and spread to the side of the adjacent unwound slot, causing the winding to sag and contacting the non-insulated portion of the stator core due to resin pressure during molding, resulting in poor insulation. There was a problem such as causing. In particular, the larger the number of windings, the more remarkable it becomes, so the amount of windings is limited and the torque characteristic is lowered. In order to improve such a problem, for example, as disclosed in Japanese Patent Publication No. 1-50309, it has been proposed to provide flanges that also serve as insulation between windings wound in each slot from the inner circumference to the outer circumference of both sides of the insulator. ing. However, if such a flange is provided, the transition part from the wound slot to the next unwound slot will ride on the flange, and it is easy to break the wire at this part, so that the winding speed cannot be increased. However, since the tension applied to the winding at the time of winding must be suppressed to a low level, the space factor becomes low and a large amount of winding cannot be wound, resulting in a low torque characteristic.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned drawbacks of the prior art and to provide a small motor having high torque characteristics.

[0004]

DISCLOSURE OF THE INVENTION According to the present invention, each slot is wound around a yoke portion of an insulator adhered to a stator core having a large number of slots separated by teeth on the inner circumference. A toroidal winding is provided, and a protrusion having a tip end portion having a width smaller than 1/2 of the width of the yoke portion is provided between the slots near the outer periphery of the side wall of the yoke portion of the insulator. The above problem is solved by.

The toroidal winding reduces the thickness, and the protrusions provided on the yoke portion on the side surface of the insulator prevent the winding from collapsing at the time of winding, and the width of the tip portion is the width of the yoke portion. Since it is set to ½ or less of that, it will not run over during winding.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. 1 is a sectional view of a small induction motor according to the present invention, FIG. 2 is a partial side view of a stator showing a state in the middle of winding, FIG. 3 is a sectional view of a part of the stator, and FIG. Similarly, in a partial side view of a stator according to another embodiment of the present invention, similarly, a state in the middle of winding is shown. In the figure,
Reference numeral 1 denotes a stator, and an insulator 5 attached to a stator core 2 having a large number of slots 4 separated by teeth 3 on its inner circumference.
A winding wire 7 for winding the yoke portion 6 in a toroidal shape is wound around each slot 4 via the and is integrally molded with a premix resin. 11 is a rotor, and end brackets 12 and 13
It is rotatably supported by ball bearings 14 and 15 supported by. 16 is an output shaft. A protrusion 8 having a width dimension L3 of its tip, which is a feature of the present invention, is set to be 1/2 or less of a width L2 of the yoke portion, which is a feature of the present invention, is provided along the outer periphery of the insulator. It prevents the winding of the wire from collapsing. In the case of the toroidal method, the winding work is carried out for each slot and then proceeds to the next unwound slot 9. However, as shown in FIG. The slots are arranged diagonally from the inner circumference side of the slot to the outer circumference of the unwound slot. Therefore, if the width of the protrusion 8 exceeds 1/2 of the width of the yoke portion, the winding will ride up, so the width is set to 1/2 or less. By setting in this way, it is possible to prevent the winding from collapsing without giving any restrictions to the winding work. It is conceivable that the positions where the projections 8 are provided are radially provided along the side surface on the outer peripheral side, but in this case, the outer diameter dimension must be increased. On the other hand, in the case of a toroidal winding, since it is wound in a fan shape, the height of the coil end is greatest on the inner diameter side and smaller on the outer diameter side, as shown in FIG. Therefore, since the protrusion is provided on the outer peripheral side where the height of the coil end is the smallest,
Since the width is within the range of the width L1, the width does not increase. If the thickness L3 of the protrusion 8 is increased,
It needs to be smaller. In the case where the strength of the protrusion is insufficient, as shown in FIG. 4, if the width L3 of the tip of the protrusion is set to 1/2 or less of L2, the width L4 of the root may be slightly larger than 1/2. There is no problem in practical use.

As described above, according to this embodiment, it is possible to prevent the winding from collapsing without interfering with the winding transition.
In addition to improving reliability and reducing defects and reducing costs, the amount of windings can be increased without increasing the external dimensions, which can improve torque characteristics and achieve higher output. You can

[0008]

According to the present invention, it is possible not only to solve the problem of winding of a toroidal winding type motor having a thin characteristic, but also to improve reliability and to achieve high output. One can greatly expand the range of applications.

[Brief description of drawings]

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

FIG. 2 is a side view of a part of the stator.

FIG. 3 is a partial cross-sectional view of the stator.

FIG. 4 is a partial side view of a stator according to another embodiment of the present invention.

[Explanation of symbols]

2 ... Stator core, 3 ... Tooth, 4 ... Slot, 5 ... Insulator,
6 ... Yoke part, 8 ... Protrusion.

Claims (1)

[Claims] 1. A stator core is provided with a large number of slots separated by teeth, and an insulator attached to the stator core is provided in the yoke portion for each slot. A toroidal winding to be wound is applied, and the tip end of the insulator is closer to the outer periphery of the side surface of the yoke portion, and the tip end thereof is 1 / the width of the yoke portion.
A small induction motor, characterized in that a protrusion having a width smaller than 2 is provided at a position between the slots.