JP2002354718A - Stator of motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve both the characteristics of a motor by reducing the resistance loss of a coil, and the performance of the motor by enlarging the area of a core facing the stator. SOLUTION: The thickness of a core 18 is small (t11) at a part 20b where a coil 24 is wound, while large (t12) at other parts 19 and 20a. Thus, the length of winding of the coil 24 is shorter, resulting in the reduced resistance of the coil 24, and so the resistance loss is smaller to improve the characteristics of a motor. Since, at the same time, the area of the core 18 facing the rotor is increased, the output torque of the motor increases, resulting in the improved performance of the motor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor stator having an improved core.

[0002]

2. Description of the Related Art The structure of a conventional motor stator is shown in FIGS. The illustrated stator of the conventional motor is an example of an outer rotor type motor, and a core 3 having a teeth portion 2 on the outer periphery (right side in the drawing) of a yoke portion 1 as shown in FIG. As shown in FIG. 10, a resin mold 6 is formed around the core 3 and a coil 7 is wound around the core 3 from above. Is equipped.

[0003]

The electric loss of a motor includes a resistance loss of a coil, which is usually called a copper loss, and is represented by the following equation.

(Equation 1)

Here, W is the resistance loss of the coil, I is the current flowing through the coil, and R is the resistance of the coil. If the resistance R of the coil is reduced, the resistance loss W of the coil is reduced, and the characteristics of the motor are reduced. improves. In this regard, the resistance of the coil 7 in the conventional motor stator is determined by the winding wire length of the coil 7 wound on the core 3 having a thickness t1. It is desired to reduce the resistance loss to reduce the resistance loss.

On the other hand, the output torque of the motor is expressed by the following equation.

(Equation 2)

Here, T is the output torque of the motor, π is the pi, D is the diameter of the core, t is the thickness of the core, and if the thickness t of the core is increased, the area facing the rotor is increased. Increases, the output torque T of the motor increases, and the performance of the motor improves. In this regard, the area of the core of the conventional motor facing the rotor is determined by the thickness t1 of the core 3, and the output torque of the motor is increased by increasing the thickness t1 of the core 3. It is desired.

However, if the thickness t1 of the core 3 is simply increased, the winding length of the coil 7 wound on the core 3 is increased, the resistance loss of the coil 7 is increased, and improvement in the characteristics of the electric motor cannot be expected. . On the other hand, if the thickness t1 of the core 3 is reduced, the characteristics of the motor can be improved, but the area of the core 3 facing the rotor is reduced, and the output torque of the motor is reduced, thereby improving the performance of the motor. I can't hope.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to improve the characteristics of an electric motor mainly by reducing the resistance loss of a coil and to increase the area of a core facing a stator. It is an object of the present invention to provide a motor stator that can achieve both the improvement of the performance of the motor and the performance of the motor.

[0009]

In order to achieve the above object, a stator for an electric motor according to the present invention is configured by winding a coil around a core. The present invention is characterized in that it is made smaller at the part where it has been made and larger at other parts (the invention of claim 1). According to this, the winding length of the coil can be reduced, and the area of the core facing the rotor can be increased.

In this case, when the core is formed by laminating magnetic plates, it is preferable to caulk the core at a portion having a large thickness (the invention of claim 2). When the core is formed by laminating magnetic plates, the thickness of the core is small in the portion where the coil is wound and is large in other portions. Other parts,
It will be composed by adding and laminating only that magnetic plate,
It is necessary to prevent the coupling of the magnetic plate in this part from being neglected (if it is neglected, the magnetic plate in this part may be dissociated).

Therefore, the core is caulked at a portion having a large thickness, that is, a portion which is to be formed by adding and laminating the magnetic plates only at other portions, whereby the magnetic plate at that portion is dissociated. A reliable connection can be made without any problem.

Also, in the case where the core is formed by laminating magnetic plates, a resin mold for covering the core including a portion having a large thickness is preferable.
In this case, the core can be bonded and bonded by a resin mold including a portion where the core has a large thickness, that is, a portion to be laminated by adding a magnetic plate of only the other portion. It is possible to perform a reliable connection without dissociation of the magnetic plate in a portion.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a stator of an outer rotor type electric motor will be described below with reference to FIGS.

First, assembling of the core will be described.
Shows the material 11 of the core magnetic plate. Although not shown in detail, the material 11 is formed by punching out three types of magnetic plates 12, 13, and 14 from the material 11 in a strip shape drawn from a state of being wound in a roll shape. In this case, the magnetic plate 12 has a portion 12a to be the yoke portion of the core and a portion 12b to be the teeth portion integrally, and the magnetic plate 13 has only the portion to be the yoke portion of the core. The magnetic plate 14 has only a portion to be the tip of the teeth portion of the core.

The rows of the magnetic plates 13 and 14 are located at the front and rear portions of the row of the magnetic plates 12 with respect to the feed direction of the material 11 indicated by an arrow A in FIG. The divided cores 15 shown in FIG. 3 are formed by sequentially stacking and caulking. The split core 15 corresponds to a plurality of annular cores, in this case, each of which is equally divided into six, and has a dovetail-shaped connecting portion 16 at each end in the circumferential direction. Dovetail connected part 17
By connecting the split cores 15 with these, an annular core 18 shown in FIG. 4 is formed.

The core 18 has a number of teeth portions 20 radially on the outer periphery of an annular yoke portion 19.
The yoke portion 19 is formed by laminating a portion 12a of the magnetic plate 12 to be a yoke portion and a magnetic plate 13, and the teeth portion 20 is formed by a portion 12b of the magnetic plate 12 to be a teeth portion.
And the magnetic plate 14.

As a result, as shown in FIG. 5, the core 18 has a portion 20b excluding the tip portion 20a of the teeth portion 20.
In this case, the thickness is as small as t11, and other portions (yoke portion 19
At the tip 20a) of the tooth portion 20, the thickness is as large as t12. The thickness t11 of the core 18 is the same as the thickness t1 of the core 3 of the conventional stator shown in FIGS.
And the thickness t12 is greater than the thickness t1 of the core 3 of the conventional stator.

FIG. 5 shows the magnetic plates 12 to 1 of the core 18.
4 shows the swaged portion 21 of FIG.
In this case, the magnetic plates 12 to 14 are joined by caulking in a V-shape, and a portion where the thickness of the core 18 is large, that is,
It is applied to a portion where the magnetic plates 13 and 14 are added to the magnetic plate 12 and laminated. More specifically, as shown in FIG. 6, the yoke portion 19 and the tooth portion 20 are each caulked at two locations for each of the tooth portions 20. On both sides (the pole piece).

Thereafter, the resin mold 22 shown in FIG. 1 is applied to the core 18. The resin mold 22 covers the entire inner surface (left side in FIG. 1), upper surface, lower surface, and both side surfaces (not shown) of the core 18 (excluding the outer peripheral surface). Including and covering parts. Further, the coating thickness of the resin mold 22 is substantially uniform as a whole, and therefore, a step 23 is formed between the thickness t11 of the core 18 and the thickness t12.

The resin mold 22 can be called an insulating member applied to the core 18. From the top of the resin mold 22, a portion of the core 18 having a thickness t 11, that is, a portion having a small thickness is provided with a coil. 24 are wound. FIG. 7 shows the entire core 18 on which the above-described resin mold 22 is formed. The core 18 has mounting bosses 25 integrally formed with the resin mold 22 at several places on the inner peripheral portion.
Is attached to a stationary member (not shown) by an attachment hole 26 provided in the hole. In the attached state, a rotor (not shown) is provided on the outer periphery of the core 18, and the rotor rotates around the outer periphery of the core 18.

As described above, in the motor of this configuration, the thickness of the core 18 of the motor stator that is formed by winding the coil 24 around the core 18 is reduced at the portion where the coil 24 is wound (t11). So that
The winding wire length of the coil 24 can be reduced. Therefore, the resistance of the coil 24 can be reduced, and the resistance loss can be reduced, so that the characteristics of the electric motor can be improved.

Further, in the present structure, the thickness of the core 18 is set to be larger (t12) in portions other than the portion around which the coil 24 is wound, whereby the rotation of the core 18 is increased. The area facing the child can be increased. Therefore, the output torque of the motor can be increased, and the performance of the motor can be improved.

Further, a step 23 is formed between the thick and small portions of the core 18, and the step 23 is formed.
Thereby, the winding of the coil 24 around the small thickness portion of the core 18 can be facilitated and surely performed. Further, the coil 24 wound around the small thickness portion of the core 18 is fixed within the height of the large thickness portion of the core 18, and is handled after production or placed on a flat surface such as at the time of mounting. It is also possible to prevent the coil 24 from being damaged, for example, when it is hit.

In addition, in the present configuration, the core 18 is formed by laminating the magnetic plates 12 to 14. In this configuration, the thickness of the core 18 is small at the portion where the coil 24 is wound, To increase the size in other parts, use core 1
In contrast to the portion around which the coil 24 is wound, the other portion is formed by laminating the magnetic plates 13 and 14 on the magnetic plate 12 alone and joining the magnetic plates 13 and 14 in this portion. Should not be neglected (if negligible, the magnetic plates 13 and 14 in this part may be dissociated).

Therefore, the core 18 is caulked at a portion having a large thickness, that is, a portion which is to be formed by laminating the magnetic plates 13 and 14 only at other portions. As a result, reliable coupling without dissociation of the magnetic plates 13 and 14 at that portion can be achieved.

Further, in the case of this configuration, the resin mold 22 for covering the core 18 including the large thickness portion is provided. Thus, the core 18 can be covered and bound by the resin mold 22 including a portion where the core 18 has a large thickness, that is, a portion to be formed by adding and stacking the magnetic plates 13 and 14 of only the other portions. Again, reliable coupling can be achieved without the magnetic plates 13 and 14 in that part being dissociated.

It should be noted that the present invention is not limited to the embodiment described above and shown in the drawings. In particular, in the motor as a whole, the inner and outer positional relationships between the yoke portion and the teeth portion of the stator core are reversed. The present invention can be similarly applied to an inner rotor type in which the rotor is positioned inside the stator and rotates, and furthermore, the yoke portion and the teeth portion of the stator core are linearly arranged together, and are opposed to each other. Then, the present invention can be applied to a linear motor in which the moving element moves linearly in the same manner, for example, and can be implemented with appropriate changes without departing from the gist of the present invention.

[0028]

As described above, according to the motor stator of the present invention, the characteristics of the motor can be improved by reducing the resistance loss of the coil, and the performance can be improved by increasing the output torque of the motor. Both can be achieved, and the winding of the coil is easy and reliable, and
There is an effect that it is possible to prevent the coil from being damaged when the coil is handled after being manufactured or placed on a flat surface.

[Brief description of the drawings]

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

FIG. 2 is a view showing a manufacturing process of a core;

FIG. 3 is a view showing a manufacturing process of the core;

FIG. 4 is a view showing a manufacturing process of the core;

FIG. 5 is an enlarged sectional view taken along the line BB of FIG. 4;

FIG. 6 is a plan view of FIG. 5;

FIG. 7 is a perspective view of the entire core in a resin molded state.

FIG. 8 shows a conventional example and is equivalent to FIG.

FIG. 9 is a diagram corresponding to FIG. 5;

FIG. 10 is a diagram corresponding to FIG. 1;

[Explanation of symbols]

12 to 14 are magnetic plates, 18 is a core, 19 is a yoke portion of the core (other portion, thick portion), 20a is a tip portion of the tooth portion of the core (other portion, thick portion), 2
Reference numeral 0b denotes a portion of the core excluding the tip end portion (a portion around which the coil is wound, a portion having a small thickness), 21 denotes a portion where the core is caulked, 22 denotes a resin mold, and 24 denotes a coil.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5H002 AA09 AB01 AB05 AC00 AC07 AC08 AE06 AE08 5H615 AA01 BB01 BB05 BB14 PP01 PP06 PP07 PP08 SS03 SS05 SS44

Claims (3)

[Claims] 1. An electric motor comprising a core wound with a coil, wherein the thickness of the core is reduced in a portion where the coil is wound and is increased in other portions. stator. 2. The electric motor stator according to claim 1, wherein the core is formed by laminating magnetic plates, and the core is caulked at a portion having a large thickness. 3. The stator for an electric motor according to claim 1, wherein the core is formed by laminating magnetic plates, and the core is formed by resin molding covering a portion including a large thickness.