JP3551732B2 - Stator for rotating electric machine - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a stator for a rotating electrical machine, and more particularly to a stator for a rotating electrical machine suitable for a diskless brushless motor or the like.
[0002]
[Prior art]
In general, a disk drive motor for office equipment is desired to be small, lightweight and highly efficient from the viewpoint of small space and energy saving. For this purpose, a brushless electric motor using a permanent magnet is optimal. In particular, in the field of small-sized brushless motors, a concentrated winding system in which most of the stator windings are concentrated and wound around the stator core teeth as disclosed in JP-A-7-298522 is adopted. .
[0003]
The above-mentioned conventional example discloses that a laminated core is divided into magnetic poles in a circumferential direction, and the stator core is formed by winding and winding and joining annularly.
[0004]
Japanese Patent Application Laid-Open No. Sho 62-203527 discloses that a slot is released and winding is performed, and then a through-window (deformation pressure absorbing space) provided in an iron core portion is compressed and deformed to hold a coil. It has been disclosed.
[0005]
[Problems to be solved by the invention]
According to the former conventional technique, the stator coil is concentrated and wound around the stator core teeth divided in the circumferential direction, so that the coil end portion of the stator coil is also short, and the space factor of the coil is increased. Therefore, there is an advantage that the physique of the electric motor can be reduced. However, the inner and outer peripheries are welded in order to make the stator core tooth portions laminated and divided into an annular shape.
[0006]
Therefore, first, the number of parts to be handled is large, and the configuration becomes complicated. Second, since the stator winding is wound directly around the divided stator core teeth, the time required for winding the coil is long, and it is difficult to wind the coil in alignment. Further, there is a problem that the space factor is not necessarily reduced, and that it cannot be said that it is easy to manufacture.
[0007]
According to the latter conventional technology, high output and high efficiency can be expected because the coil area factor is increased. However, since the coil locking piece of the tooth portion is simply provided after the winding, the size and weight can be reduced. I can't connect.
[0008]
An object of the present invention is to provide a stator of a rotating electric machine that is small and lightweight and can achieve high efficiency.
[0009]
SUMMARY OF THE INVENTION It is an object of the present invention to provide a stator for a rotating electrical machine having a small size and a laminated core having a high winding space factor.
[0010]
[Means for Solving the Problems]
The present invention relates to an iron core steel plate in which a plurality of teeth are arrayed in a ring with a connecting piece at a yoke portion located at an inner peripheral portion or an outer peripheral portion of a tooth portion, and a shape formed by laminating the shape steel plates. This is achieved by winding a coil around the teeth of the laminated core and then compressing and deforming the laminated core from the outer peripheral direction to a predetermined outer diameter to form a stator core.
[0011]
Preferably, the present invention is achieved by absorbing the compressive deformation pressure by a deformation pressure absorbing space formed at the root of the tooth portion.
[0012]
Preferably, the present invention is achieved by absorbing the compressive deformation pressure by a deformation pressure absorbing space formed in the outer yoke portion of the tooth portion.
[0013]
The present invention is achieved by applying a coil with the slots of the elementary laminated core formed by lamination being released, and then compressively deforming the stator from the outer peripheral direction to obtain a stator core.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
First Embodiment FIG. 1 shows a state diagram of a laminated core of a stator for a rotating electric machine and a state diagram of a stator coil winding according to a first embodiment of the present invention. It is a structure of a stator core for a type motor.
[0015]
As shown in FIG. 1, the stator core is composed of a laminated core 1 in which a plurality of teeth 12 are radially formed on an inner peripheral yoke portion 11, and a stator coil 2 wound around each of the teeth 12. The teeth 12 are arranged in a ring shape with a slot gap g of several millimeters.
[0016]
Each of the steel sheets of the elementary laminated iron core 1A which is the original form of the laminated iron core 1 is formed by punching or etching a magnetic steel sheet (for example, 35S210) as shown in FIG. That is, as shown in FIG. 2, the shaped steel plate of the iron core is provided with a connecting piece 14 extending from the root portion 13 of the tooth portion so that the deformation pressure absorbing space 3 is formed between the inner peripheral yoke portion 11 and each tooth portion 12. ing. On the other hand, one side of the anti-joint is an open end 4 and its corners are engagement ends 15 and 16. Then, the formed steel sheet is laminated at a predetermined plate pressure to form a formed laminated iron core 1A which is an original form of the laminated iron core 1.
[0017]
Next, the winding process of the stator coil 2 is performed. In this state, the space between the teeth 12, that is, the slot space 5 is provided so as to be widened to the extent that the nozzle of the winding machine can move sufficiently. Concentrated winding of the coil is speedy and effective.
[0018]
At this time, the cross section of the slot space 5 in which the stator coil 2 enters can be made large because the inner diameter and the outer diameter of the winding portion of the elementary laminated iron core 1A are large by the deformation pressure absorption space 3, and the opening of the slot space 5 The width G (slit between the stator core teeth 12) is increased by an increase in the outer diameter. That is, the stator coil 2 can be wound with a large number of turns or the wire diameter of the winding can be increased by an amount corresponding to the increase in the sectional area of the slot space 5.
[0019]
When the coil is applied to the elementary laminated iron core 1A, it is compressed and deformed from the outer peripheral direction to a predetermined outer diameter, that is, when the deformed pressure absorbing space 3 is compressed and deformed to zero, the connecting piece 14 becomes the stator coil 2A. Are plastically deformed along the bottom side, and the engagement ends 15 and 16 of the open ends are firmly engaged with each other and are firmly connected. The target of the compression space due to the plastic deformation is zero as described above. However, in consideration of the easiness of the plastic deformation or the springback at the time of the plastic deformation, an escape space 31 for the plastic deformation is provided in the connecting piece 14 in advance. Good to keep. Thereby, plastic deformation is performed with high accuracy.
[0020]
What is important here is that the teeth 12 are concentrically compressed and deformed, thereby preventing damage to the coil and reducing the compression space to zero to minimize magnetic loss. One example will be described with reference to FIGS. 3 and 4 show a jig for compressing and deforming the laminated core by a press machine. The jig is provided with a fixing jig 100 having a cylindrical inner surface tapered, and disposed in contact with the tapered surface of the fixing jig, and has a triangular cross section that moves along the tapered surface of the fixing jig 100. The sliding piece 200 includes a holding jig 300 that holds the inner diameter of the elementary laminated iron core 1A and guides the sliding of the sliding piece 200. The sliding pieces 200 are arranged in the circumferential direction by the number corresponding to the tooth portions of the elementary laminated iron core, and a force in the axial direction is applied by a component force of a taper surface between the fixing jig 100 and the sliding piece 200 in a radial direction. Then, the deformed pressure absorbing space 3 of the shaped laminated core 1A is compressed by applying pressure to the shaped laminated iron core teeth 12.
[0021]
Here, the number of the sliding pieces 200 arranged in the circumferential direction corresponds one-to-one with the elementary laminated iron core teeth 12, and applies pressure to all the elementary laminated iron core teeth 12 simultaneously and uniformly. That is, the predetermined number of the sliding pieces 200 is 9 in the case of the elementary laminated iron core 1A having nine teeth. The compression-deformed elementary laminated core 1 </ b> A is wound around the stator coil 2 and is fixed to the center of the sliding piece 200, and the radial direction generated by the pushing amount of the sliding piece 200 with respect to the fixing jig 100. Is compressed and deformed by the component force. At this time, the pressure at the time of compression is adjusted by the feed amount of the sliding piece 200, and a pressure is applied to each of the element laminated iron core teeth 12A via the sliding piece 200 to absorb the deformation pressure of the element laminated iron core 1A. Crush space 3.
[0022]
Thereby, all the deformation pressure absorption spaces 3 of the laminated core 1 can be crushed almost simultaneously, so that the accuracy of the shape of the laminated core 1 after the compressive deformation pressure can be secured.
Second Embodiment FIGS. 5 and 6 show a second embodiment. The difference from the first embodiment is that, as can be seen from FIG. 6, the deformed pressure absorbing space of the elementary laminated iron core 1B. 3A is formed by punching. As a result, the connecting pieces 14a and 14b are located on both sides of the iron core tooth portion 12B so as to be evenly balanced and plastically deformed when the elementary laminated iron core 1B is compression molded. Of course, in order to increase the accuracy of plastic deformation, it is preferable to provide deformation pressure absorbing spaces 31, 32 in the respective connecting pieces 14a, 14b.
[0023]
Third Embodiment FIGS. 7 and 8 show a stator according to a third embodiment when used in an adduction type magnet motor. In FIG. 7, the laminated laminated core 20 </ b> A has a connecting piece 21 </ b> A at a position corresponding to between the magnetic poles of the outer yoke 21. The connecting piece is hung obliquely from the outer circumference to the inner circumference, thereby forming deformed pressure absorbing spaces 21a and 21b inside and outside the outer yoke 21 respectively. After the stator coil 2 is wound around the thus formed elemental laminated steel sheet 20A laminated to a predetermined thickness, it is compressed and deformed concentrically by the same jig as in the above-described embodiment. As a result, the deformation pressure absorbing spaces 21a and 21b become clogged to zero, and the slot space G also becomes clogged to the predetermined gap g.
[0024]
The laminated iron core thus formed is generally used by covering it with an aluminum cylindrical casing 22 as shown in FIG. 8 in order to obtain the coupling force of the butted portions 21c and 21d generated by compression deformation. Alternatively, the butted portions may be joined by welding.
[0025]
Fourth Embodiment FIG. 9 shows a stator according to a fourth embodiment which is used in an adduction type magnet motor as described above. In the figure, the elementary laminated iron core 40 is provided with a slit 41a in the shape of a "<" from the inner periphery to the outer periphery of the outer yoke portion 41, and the outer periphery thereof is formed so that the respective tooth portions 42 are connected in an annular shape. Are connected by a connecting piece 41b projecting to the outer periphery. The connecting piece 41b acts as a deformation pressure absorbing space at the time of compression molding of the elementary laminated core 40 to enhance the molding accuracy. In use, if pressed into an aluminum casing, the connecting piece acts as a detent effect to provide a stator with high mechanical strength.
[0026]
Fifth Embodiment FIGS. 10, 11, and 12 show a fifth embodiment, in which the dimensional ratio (slot opening ratio) of the slot pitch and the width g of the opening of the slot space in the first embodiment is described. ).
[0027]
The vertical axis in FIGS. 10 and 11 shows the case where the stator outer diameter φ = 20 mm and the slot opening ratio is 16% as a reference value, and converts each measured value into a ratio to the reference value. In addition, the value of the slot structure as a reference is a general dimension when an automatic winding machine is used when the stator outer diameter φ is 20 mm. The motor was an external rotation type brushless motor having a permanent magnet field of 2 to 5 W class.
[0028]
As shown in FIG. 11, the factors of the motor vibration of the permanent magnet field include a cogging torque generated when the rotor rotates and a commutation torque ripple generated when the motor is energized.
[0029]
The cogging torque is generated when a gap between the permanent magnet and the stator core changes (permeance changes) at the slot opening when the rotor rotates, and the slot opening ratio of the stator core decreases. By doing so, the cogging torque can be reduced. When the outer diameter of the stator is increased, the output torque can be increased since the surface area of the permanent magnet disposed outside the stator can be increased, but the cogging torque also increases.
[0030]
On the other hand, the commutation torque ripple ΔT causes torque fluctuation due to the current delay Dt due to the reactance of the stator winding, and the commutation torque ripple increases when the slot opening ratio of the stator core is reduced. This is because when the width g of the slot opening is reduced, the reactance of the stator winding increases due to an increase in leakage reactance at the slot opening.
[0031]
In FIG. 12, the commutation torque ripple is generated when the winding currents Iu, Iv, Iw flow by switching the phases of the winding applied voltages Vu, Vv, Vw of the U, V, W phase stator windings (commutation). Due to the reactance of the winding, the winding current is delayed from the applied voltage by a delay Dt, and the total output torque of each of the U, V, and W phases drops every time the phase is switched to become a pulsating torque. This pulsation is the commutation torque ripple ΔT. Here, the W-phase winding current Iw and the winding applied voltages Vv and Vw are not shown.
[0032]
When the stator outer diameter is increased, the amount of magnetic flux of the permanent magnet can be increased, so that the same output torque can be obtained with a small winding current value. In other words, when trying to obtain the same output torque as φ16 using φ24 having a large stator outer diameter, the winding current can be reduced, so that the effect of the winding current can be reduced and commutation torque ripple should be reduced. Can be.
[0033]
As shown in FIG. 10, motor vibration (peripheral vibration) generated by these two torque ripple components vibrates the entire apparatus via a motor mounting portion, and causes vibration and noise. The relationship between the motor vibration ratio and the slot opening ratio becomes a downwardly convex curve and has a minimum value.
[0034]
When the slot opening ratio at which the motor vibration becomes the minimum value regardless of the stator outer diameter is obtained below the reference value, the slot opening ratio at the intersection of the stator outer diameters φ24 and φ16 is 12.5% or less and the stator outer diameter is less than 12.5%. It can be seen that the slot opening ratio at the intersection of the diameters φ24 and φ20 should be set to a range of 5% or more.
[0035]
As described above, if the slot pitch ratio of the stator core and the width dimension ratio of the slot opening according to the present invention are applied to a permanent magnet field motor, vibration and noise can be reduced.
[0036]
【The invention's effect】
According to the present invention, since the coil is formed with the slots of the elementary laminated cores formed by lamination being released, and then compressed and deformed from the outer peripheral direction to form the stator core, compactness, light weight and high efficiency can be achieved. Thus, it is possible to provide a stator for a rotating electric machine.
[Brief description of the drawings]
FIG. 1 is a front view of a stator core after winding in one embodiment of the present invention.
FIG. 2 is a front view before processing in FIG. 1;
FIG. 3 is an arrangement transverse sectional view of a jig and a stator core used in the present invention.
FIG. 4 is a cross-sectional view of a main part in FIG. 3;
FIG. 5 is a front view of a stator core after winding in another embodiment of the present invention.
FIG. 6 is a front view before processing in FIG. 5;
FIG. 7 is a front view of a stator core before machining according to still another embodiment of the present invention.
FIG. 8 is a front view of the stator core showing the use state of FIG. 7;
FIG. 9 is a front view of a stator core before machining according to still another embodiment of the present invention.
FIG. 10 is a diagram showing the relationship between motor vibration and slot opening ratio.
FIG. 11 is a diagram showing the relationship between motor vibration factors in FIG. 10;
FIG. 12 is an explanatory diagram of a commutation torque ripple in FIG. 11;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Laminated iron core, 1A, 1B, 20A ... Elementary laminated iron core, 2 ... Stator coil, 3, 3A, 21a, 21b, 31, 32 ... Deformation pressure absorption space, 5 ... Slot space, 11 ... Inner circumference yoke part, 12 ... tooth part, 13 ... root of tooth part, 14, 14a, 14b, 21A ... connecting piece.

Claims (6)

In a rotating electric machine having a stator in which iron core shaped steel plates in which a plurality of teeth are arrayed in a ring with a connecting piece at a yoke portion located at an inner peripheral portion or an outer peripheral portion of a tooth portion are laminated, the tooth portions of the stator A rotary electric machine, wherein a coil is wound around the base, and a deformation pressure absorption space provided at a root portion of the tooth portion is compressed to form a stator. According to claim 1, wherein the rotating electric machine, characterized in that absorbed by the compressive deformation pressure formed on the outer peripheral yoke portion of the tooth portion deformation pressure absorbing space. According to claim 1, wherein the rotating electric machine deformation pressure absorbing space is characterized in that it is formed by connecting pieces formed on at least one of the root portion of the teeth. According to claim 1, wherein the deformation pressure absorbing space is formed by connecting pieces formed on at least one of the root portion of the teeth, rotary electric machine, characterized in that as the engaged end of the reaction tie one open end. In claim 2, the rotational electric machine, characterized in that the deformation pressure absorbing space is formed by connecting pieces formed in the outer circumferential yoke portion of the teeth. According to claim 1, wherein the rotating electric machine, characterized in that setting the slot pitch and the width ratio of the slot opening of the stator core in the range of 5% to 12.5%.

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