JP2017028962A - Manufacturing method and manufacturing apparatus for stator core of rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method and a manufacturing apparatus that can manufacture a laminated core 1 (stator core) comprising a cut part 14 for through bolt fitting insertion at an outer periphery from a belt-like core sheet with high circularity.SOLUTION: In a finishing process of shaping a laminated core 1 into a desired circular shape by carrying out ironing processing on inner- and outer-diameter sides of the laminated core 1, the ironing processing is carried out while pressing force is applied to a cut part 14 from an outer-diameter direction to an inner-diameter direction. Consequently, a deformation event is prevented from occurring to a periphery of the cut part 14 during the ironing processing, and the laminated core 1 (stator core) having high circularity can be thus obtained. Further a support member 206 fitted in the cut part 14 is used as means of applying the pressing force to the cut part 14 to achieve implementation with a simple constitution made by only adding a plurality of support members 206 to an existing shaping device 200, which is economical in terms of facilities.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a method of manufacturing a laminated core type cylindrical stator core suitable for a stator core of a rotating electrical machine, particularly a stator of an automotive alternator, and to effectively embody the manufacturing method. It relates to a manufacturing apparatus.

[Conventional technology]
Conventionally, laminated core type cylindrical stator cores have been put to practical use in various configurations. In recent years, teeth (teeth) portions and slots (from a magnetic plate (for example, a steel plate) to the inner peripheral side) Instead of a laminated core that is formed by punching an annular plate with a groove) and laminating a large number of annular plates into a cylindrical shape, a strip-shaped magnetic plate is used as an iron core material because it has little waste material and good material yield. A core sheet is formed by punching and forming a tooth part and a slot part on one side (one side in the width direction), and this strip-like core sheet is wound in a spiral shape (helical) and wound into a plurality of layers in a cylindrical shape. Laminated core-type stator iron cores that are laminated, so-called “rolled iron cores” have come to be used exclusively.

In particular, in a rotating electrical machine with severe price constraints such as an AC generator for automobiles, the material cost can be reduced, and this wound core type stator core is awarded.
The wound core type stator core (laminated core) has to be formed into a cylindrical shape while winding a belt-like core sheet in a spiral shape (helical). In order to eliminate misalignment between each winding layer that cannot be absorbed by the winding process and the sizing process, a finishing process is performed to shape the desired round shape as the final process. It is customary (see Patent Document 1).

That is, when the manufacturing process is roughly divided into the wound core type, a pressing step (first step) for producing a band-shaped core sheet in which a tooth portion and a slot portion are punched and formed on one side in the width direction, and the core sheet A winding step (second step) in which a plurality of layers are wound in a cylindrical shape while being spirally wound to form a laminated core, and this laminated core is cut into predetermined laminated dimensions (thicknesses) to form each wound layer. A sizing process (third process) for fixing so as not to shift, and a finishing process (fourth process) for shaping the laminated core into a desired perfect circle shape by ironing the inner and outer diameter sides thereof. Four processes are the basic processes.

By the way, in recent automobiles, in order to adapt to various demands such as improvement of engine performance and improvement of comfort in the passenger compartment with the rapid spread and development, it is installed especially in the engine room. The number of devices used is rapidly increasing, and these on-board devices are subject to strict restrictions on miniaturization and high performance without exception, and the above-mentioned AC generators must be further miniaturized and improved in performance. There is no situation.

Therefore, in this type of rotating electrical machine, securing a desired perfect circular shape in the stator core ensures the proper slot pitch and contributes significantly to the increase in the space factor of the stator coil. Since it is a requirement, high performance is pursued by obtaining a high-quality stator core having a higher roundness.
Further, from the viewpoint of miniaturization, a case in which the stator core itself is effectively used as a part of a casing of a rotating electrical machine by sandwiching and fixing both ends of the stator core with a pair of saddle type casings has become common. ing. At that time, in order to secure an arrangement space for a clamping member (through bolt) for clamping and fixing, a notch portion for inserting a through bolt is provided in the axial direction on the outer peripheral edge of the stator core at intervals of 90 °, for example. This is usually provided.
Depending on the required specifications of the stator core, the laminated core is fixed by effectively using the notched portion extending in the axial direction, that is, each winding layer of the laminated core without increasing the outer diameter of the stator core. In some cases, welding is performed at the notch as a means for fixing the wire.

[Problems of the prior art]
Thus, in rotating electrical machines such as automotive alternators, various improvements have been made to the structure and manufacturing in order to pursue miniaturization and high performance, but it is still insufficient. There is a need for further improvements.

The present inventor has conducted a number of experiments and research, aiming at further raising the roundness of the stator core, in particular, but this time the manufacturing process from the winding process to the finishing process of the stator core As a result of scrutinizing, the following problems were identified.

(1) As described above, the wound core type stator core has a difficulty in securing high roundness due to the nature of having to form a cylindrical core sheet while spirally winding the belt-shaped core sheet. In order to eliminate the misalignment between the winding layers that cannot be absorbed in the winding process and the sizing process, a finishing process for shaping into a desired perfect circle has been performed as a final process.
(2) However, if this finishing process is examined in detail, a deformation event occurs unexpectedly with respect to the laminated core during the ironing process, and the stator core is moved to a desired perfect circle due to this deformation event. It has been found that it cannot be shaped into a shape, which may lead to problems such as damage to the stator coil.

(3) That is, in the finishing process, misalignment or the like is corrected by ironing the inner and outer diameter sides of the laminated core after welding, so that it is considered that a desired perfect circular shape is secured. However, in the type in which the notch portion is provided on the outer peripheral edge of the stator core, a deformation phenomenon (deformation region) has also occurred around the notch portion.

This deformation area has been overlooked because the number of cutouts is small (about 4 places around the entire circumference), but the yoke part in the vicinity due to slight displacement around the cutout, such as the cutout itself being crushed. As a result of deformation in the teeth and the slot, the slot pitch of the stator core shifts, resulting in performance degradation and damage to the stator coil, that is, the stator coil space factor (stator If the stator coil moves due to vibration during operation, etc., the stator coil will interfere with the above deformation area and damage the insulation film of the coil wire. It has been found that the problem will develop.

JP 2009-77561 A JP 2014-1211136 A

  The present invention has been made to solve the above-described problems, and the object of the present invention is to prevent a deformation region from being generated around the cutout portion of the laminated core, and to increase the occupation of the stator coil. Providing a manufacturing method for obtaining a high-roundness stator core capable of securing a volume factor and high reliability, and manufacturing capable of realizing such a manufacturing method economically and with high quality To provide an apparatus.

[Means of Claim 1]
The invention according to claim 1 (method for manufacturing a stator core of a rotating electrical machine) is for obtaining a wound core type stator core using a strip-shaped core sheet, and with respect to the core sheet, in the width direction. A tooth portion and a slot portion constituting a plurality of magnetic poles for winding the stator coil are formed on one side of the yoke, and a yoke portion and a plurality of notches are formed on the outer peripheral edge on the other side in the width direction. The pressing step and the core sheet are laminated in a cylindrical shape while being spirally wound so that the magnetic poles are on the inner peripheral side, and the teeth portion, the slot portion, and the notch portion are laminated in the axial direction. A winding step for forming the core, a sizing step for cutting the laminated core into predetermined laminated dimensions and fixing the wound layers of the laminated core so as not to shift, and inner and outer diameters of the laminated core. On the side Is a basic configuration in that it comprises four steps and the finishing step of shaping the laminated core in the desired circular shape by performing molding can.

  In the manufacturing method of the present invention, in the finishing process, the iron forming process is performed while applying pressing force from the outer diameter direction to the inner diameter direction with respect to the plurality of notches when performing the iron forming process on the inner and outer diameter sides of the laminated core. It is characterized by carrying out.

  According to the method of the present invention having the above-described configuration, it is possible to prevent deformation around the notch portion during the ironing process of the laminated core and obtain a highly round stator core. Therefore, there is no deviation in the slot pitch, and even if the amount of storage of the stator coil is increased or the stator coil moves due to vibration during operation, the stator coil is not damaged, The high space factor and high reliability of the stator coil can be ensured, which can greatly contribute to the downsizing and high performance of the rotating electrical machine.

[Means of claim 4]
According to a fourth aspect of the present invention (a manufacturing apparatus for a stator core of a rotating electrical machine), the shaping device for performing the ironing forming process includes a core bar for shaping the inner diameter side of the laminated core, and an outer surface of the laminated core. An annular ironing ring for shaping the radial side, and a plurality of support members for applying a pressing force from the outer diameter direction to the inner diameter direction with respect to each notch portion of the laminated core.
The plurality of support members form a rod-like body having a cross-sectional shape projecting from the recess shape of the notch portion along the axial direction, and the projecting portion is a laminated core made of the core metal and the ironing ring. It is characterized by being inserted into each notch at the time of shaping.

  According to the device of the present invention having the above-described configuration, from the outer diameter direction to the inner diameter direction with respect to each of the plurality of notches, with a simple configuration and inexpensive capital investment by simply adding a plurality of support members to the existing device. It is possible to obtain a high-roundness stator core by carrying out ironing forming processing while reliably applying a pressing force of. Therefore, the stator core manufacturing method according to the means of claim 1 can be realized economically and with high quality.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 schematically shows an automotive alternator that is a typical example of a rotating electrical machine to which a stator core manufactured by the method of the present invention and the device of the present invention is applied. (A) is a half showing the overall configuration of the generator. Sectional drawing, (b) is a front view of the upper half part which shows the form of a stator core single-piece | unit along the AA line of (a). The principal part of the stator core manufactured by this invention method and this invention apparatus is shown, (a) is a front view of the core sheet | seat produced at a 1st process (press process), (b) is (a). Sectional drawing which follows BB line | wire of (b), (c) is a front view of the core sheet used for description of the winding process in a 2nd process (winding process), (d) is the laminated core obtained through the 2nd process FIG. It is typical process drawing with which it uses for the outline | summary description of all the processes (1st process-4th process) by this invention method and this invention apparatus. In order to explain the problems to be solved by the method of the present invention and the device of the present invention, (a) is a front view of the main part of the laminated core obtained through the third step (sizing step), and (b) is (a) It is sectional drawing in alignment with CC line | wire. For the explanation of the problems to be solved by the method of the present invention and the device of the present invention, (a) to (e) are schematic views showing the detailed process in the fourth step (finishing step) divided into five steps. FIG. 9 is a front view of a principal part for explaining a problem to be solved by the method of the present invention and the device of the present invention and showing the shaping state of the laminated core in the fourth step. It is a principal part front view which uses for description of the central function in this invention method and this invention apparatus, and shows the shaping state of the lamination | stacking core in a 4th process. FIG. 2 is a schematic longitudinal sectional view of a main part of a shaping device, and FIG. 2B is an enlarged perspective view of a central functional part.

  Hereinafter, the best mode of a manufacturing method and a manufacturing apparatus for carrying out the present invention will be described in detail according to embodiments shown in the drawings.

In this embodiment, the manufacturing method and the manufacturing apparatus of the present invention are shown as an application example to a stator core of an automotive alternator (alternator), which is a typical example of a stator core of a rotating electrical machine. In the description, first, the basic configuration of the AC generator for automobiles is outlined, then the basic configuration and characteristic functions of the method and the device of the present invention are sequentially described, and finally the features of the method and the device of the present invention. Summarize the effects of each point.
In each figure, the same or equivalent parts are denoted by the same reference numerals, and redundant description is omitted.

[Example 1]
Based on FIG. 1 and FIG. 2, the basic configuration of an automotive alternator 100 (hereinafter abbreviated as “generator 100”) to which an embodiment of the production method and production apparatus of the present invention is applied will be described.

[Basic configuration of generator 100]
As shown in FIG. 1A, the generator 100 includes a rotor 102 attached to a rotating shaft 101 driven by an engine, and a pair of cups (椀) by through-bolts (tightening members) 103 for clamping and fixing. And a stator 106 sandwiched between mold-shaped casings 104 and 105. In this stator 106, a stator core 108 made of a cylindrical laminated core 1 called a “winding core” is used as an iron core around which a stator coil (multiphase winding) 107 is wound. In particular, the stator core 108 is used as a part of the casing of the generator 100 by being sandwiched and fixed between a pair of cup-shaped casings 104 and 105.

As shown in FIG. 1B, the stator core 108 has an annular shape as a whole, and includes a large number of teeth constituting magnetic poles corresponding to the number of phases around which the stator coil 107 is wound. (Teeth) portions E1 and slots (grooves) E2 are provided alternately, and a cylindrical shape is provided with a yoke (junction) portion E3 that annularly connects each tooth portion E1 and slot portion E2 at a predetermined pitch on the outer peripheral side. It is composed of a laminated core 1.
The annular yoke portion E3 is a non-winding portion around which the stator coil 107 is not wound, and four notches E4 are arranged in the axial direction on the outer peripheral edge of the yoke portion E3 at a predetermined interval of 90 °, for example. It is formed by extending over the entire area. This notch E4 constitutes a recess into which the through bolt 103 can be inserted, and has a semicircular shape that is recessed from the outer diameter direction toward the inner diameter direction.

  In the present description, although the stator core 108 and the laminated core 1 have substantially the same structure, the stator core 108 and the laminated core 1 are distinguished from each other and given different reference numerals. However, basically, the one having a predetermined shape that has been finished through the final manufacturing process is called a “stator core 108”, and the one in the middle of the manufacturing process is called “laminated core 1” from its form. Shall be called.

[Basic structure of laminated core 1]
The laminated core 1 uses a belt-like core sheet 10 as shown in FIGS. 2A and 2B as an iron core material. The core sheet 10 has teeth (teeth) portions 11 (E1) and slot (groove) portions 12 (E2) that constitute magnetic poles for winding the stator coil 107 on one side in the width direction. In addition, a yoke (junction) portion 13 (E3) for connecting the teeth portion 11 and the slot portion 12 at a predetermined pitch is provided on the other side in the width direction. On the side, an appropriate number (for example, four) of semicircular cutout portions 14 (E4) for forming recesses for inserting through bolts at predetermined intervals (for example, 90 ° intervals) are provided.

The core sheet 10 is produced, for example, as a pair (two sheets) of band-shaped core sheets by punching out a wide band-shaped magnetic plate so that the teeth portions 11 and the slot portions 12 are alternately arranged, or A single belt-like core sheet is produced by punching a narrow belt-like magnetic plate so that the teeth 11 and the slots 12 are alternately arranged on one side thereof.

Then, as shown in FIG. 2C, the core sheet 10 is spirally wound so that the yoke portion 13 (and the notch portion 14) is on the outer peripheral side, and the teeth portion 11 (E1). The slot 12 (E2) and the notch 14 (E4) are aligned in the axial direction and are wound and laminated over a plurality of layers to form a cylindrical laminated core 1 as shown in FIG.
Thereafter, a final stator core 108 is obtained by performing a sizing process and a shaping process on the laminated core 1.

  Next, a specific method for manufacturing the stator core 108 (laminated core 1) having the above-described configuration will be described.

The manufacturing method of the present embodiment can be broadly divided into a first step (pressing step) for producing the core sheet 10, a second step (winding step) for winding the core sheet 10 in a spiral manner, and cutting for each predetermined stacking dimension. Then, through the third step (fixed size step) for fixing each winding layer by welding, the laminated core 1 is subjected to shaping processing such as ironing and finished to the fourth step (finishing step) to finish the stator core 108. It consists of processes.

  First, the steps from the first step to the fourth step will be outlined in accordance with the schematic process diagram shown in FIG.

○ 1st process (press process)
This first step is a well-known step that is generally employed. For example, a wide strip-shaped magnetic plate T such as a strip steel (SPCC) is sequentially applied to appropriate punching means U and V such as a continuous press device. The two core sheets 10 that are divided into two in the length direction are manufactured by performing the punching process in multiple stages.
Thus, the core sheet 10 as shown in FIG. 2A, that is, the teeth portion 11 and the slot portion 12 are formed on one side in the width direction, and the teeth portion 11 and the slot portion 12 are provided on the other side in the width direction. A band-shaped core sheet 10 is obtained in which the yoke portions 13 are connected at a pitch of 5 mm, and a plurality of notches 14 are formed on the edge (outer peripheral edge) of the yoke portion 13.

○ 2nd process (winding process)
In this second step, the belt-shaped core sheet 10 is conveyed in the length direction, and bending is performed so that the core sheet 10 is bent with a predetermined winding diameter so that the yoke portion 13 is on the outer peripheral side. In this step, the winding shaft is used as a winding step as in Patent Document 1, that is, as a bending means for bending the core sheet 10 so that the yoke portion 13 is on the outer peripheral side. The process of winding the core sheet 10 directly around the outer periphery in a spiral manner is widely used.

Incidentally, in this embodiment, the winding process introduced in Patent Document 2 is illustrated as another specific example.
In this winding process, a roller device (roller means) 20 is used as the bending means X disposed along the winding path W. This roller device 20 is composed of two-stage roller means 20A and 20B, and each stage of roller means is basically arranged inward of the winding path W in the radial direction of the curvature of the winding path W. And a pair of second rollers 22 and 23 arranged so as to sandwich the first roller 21 from the circumferential direction on the radially outer side of the curvature of the winding path W. The first roller 21 serves as a driving side, and the pair of second rollers 22 and 23 is driven by the first roller 21 to follow and rotate, and rotate in opposite directions.

When the core sheet 10 is inserted into the roller device 20, the first roller 21 and the second roller 22, while the inner and outer circumferences are pressed at three locations by the first roller 21 and the pair of second rollers 22 and 23, In this process, it is bent along the winding path W and bent into a curved shape.
As described above, the core sheet 10 is spirally wound and formed in a cylindrical shape so that the yoke portion 13 is on the outer peripheral side by being formed into a curved shape by the roller device 20. The layered tooth portion 11, the slot portion 12, and the notch portion 14 are aligned in the axial direction to produce the laminated core 1 as shown in FIG.

○ Third step (fixed size step)
This third step is also a general well-known step as introduced in Patent Document 1. In this step, since the laminated core 1 formed in a cylindrical shape in the previous step is in a continuous laminated state, the laminated core 1 is cut for each predetermined laminated dimension (thickness) so that each wound layer is not displaced. It is fixed by welding with appropriate welding means such as torch welding at the notch 14 at the outer peripheral edge, and is taken out as a single laminated core 1.

○ Fourth process (finishing process)
Finally, the laminated core 1 is put into the finishing process. In this finishing process, an appropriate shaping means Y for performing ironing processing on the inner and outer diameter sides of the laminated core 1 is provided, and the roundness on the outer diameter side and the concentricity on the inner diameter side of the laminated core 1 are corrected and shaped. To do.
Thus, the final laminated core 1 having a predetermined perfect circular shape, that is, the stator core 108 is obtained.
It should be noted that improving the finishing process forms the basis of the method of the present invention, and details thereof will be described later.

  As shown in FIG. 1A, the stator core 108 completed as described above is sequentially passed through a conventionally known general winding process and assembly process, and the stator coil 107 is placed in the teeth portion E1. Is installed in the generator 100 as a stator 106.

  By the way, in the above-described manufacturing process, the laminated core 1 must be formed in a cylindrical shape while winding the strip-shaped core sheet 10 in a spiral shape, and therefore, it is an intermediate process (in particular, a winding process, a sizing process). In the stage, due to the displacement of each winding layer, variation in dimensions occurs in each part. This variation will be supplemented with reference to FIG.

As shown exaggeratedly in FIGS. 4 (a) and 4 (b), the laminated core 1 has the respective winding layers 1a, 1b,... 1c. The side surfaces of the teeth portion 11 (E1) and the slot portion 12 (E2) have uneven surfaces in the circumferential direction and the radial direction. That is, the teeth portion 11 (E1) and the slot portion 12 (E2) are not neatly aligned, and the laminated core 1 is distorted to the roundness on the outer diameter side and the concentricity on the inner diameter side, the U-shape of the slot portion 12 ( Deformation).
In order to correct the distortion (deformation) of the laminated core 1, as described above, a “finishing process” for shaping the inner and outer diameter sides of the laminated core 1 by ironing is performed as the fourth process.

However, when this “finishing process” is examined in detail, an unexpected deformation event occurs in the laminated core 1 during the ironing process, and the stator core 108 is shaped into a desired perfect circle shape due to this deformation event. Thus, it has been found that there is a risk of causing problems such as a shift in slot pitch and damage to the stator coil 107.

[Outline of “finishing process”]
Here, as the “finishing step”, a typical finishing step introduced in Patent Document 1 will be outlined with reference to FIG.

First, a basic configuration of a shaping device 200 used as shaping means for executing ironing forming processing will be described with reference to FIG.
In FIG. 5A, the shaping device 200 includes a cylindrical workpiece receiver 201 that supports the laminated core 1 that is a workpiece, and a cylindrical shape that is accommodated in the workpiece receiver 201 and shapes the inner diameter side of the laminated core 1. A cored bar 202 and a slot aligning arrow arranged on the outer peripheral side of the cored bar 202 along the circumferential direction according to the number of slots and shaping the teeth portion 11 (E1) and the slot portion 12 (E2) of the laminated core 1 203, a work holder 204 that presses the laminated core 1 against the work receiver 201, an annular ironing ring 205 that shapes the outer diameter side of the laminated core 1 while sliding on the outer periphery of the workpiece receiver 201 and the work holder 204, and Drive means (for example, a hydraulic press etc.) which drives each member 202-205 (not shown) are provided.

Next, when the laminated core 1 is finished into the stator core 108 having a predetermined shape by using the shaping device 200, the finishing process is divided into five steps and sequentially described.

First, in step 1, as shown in FIG. 5A, the laminated core 1 is put into the shaping device 200. Here, the laminated core 1 is in a state in which the peripheral edge portion is welded in a sizing process, which is a preceding process, and the wound layers are fixed so as not to be displaced from each other. Placed on. Further, the workpiece receiver 201 is a fixed type, and the outer diameter thereof is set slightly smaller than the outer diameter of the laminated core 1 (a size corresponding to the normal core outer diameter).

Next, as shown in FIG. 5B, as shown in FIG. 5B, the work clamp 204 is lowered as indicated by an arrow to fix the laminated core 1 to the work receiver 201. The outer diameter of the work holder 204 is also set to be slightly smaller than the outer diameter of the laminated core 1 (to a size according to the regular core outer diameter). The workpiece receiver 201 and the workpiece presser 204 are arranged coaxially, and the laminated core 1 (its outer diameter side) is used as described later by utilizing the difference in diameter between the outer diameter and the outer diameter of the laminated core 1. The ironing process is applied to the surface.

In the subsequent step 3, as shown in FIG. 5C, the cored bar 202 and the slot aligning arrow 203 which are disposed inside the work receiver 21 so as to be movable up and down are raised as shown by the arrows. At this time, both the cored bar 202 and the slot aligning arrow 203 are fitted from the lower end (one axial end side) of the laminated core 1 and penetrate to the upper end side (the other axial end side).
Here, the outer diameter of the cored bar 202 is set to be slightly smaller than the inner diameter of the laminated core 1 (so as to absorb the inner diameter side error of the laminated core 1 in the previous process), whereas each slot alignment is made. The arrows 203 have a cross-sectional shape that conforms to the regular slot shape, and are arranged in the circumferential direction at regular slot pitch intervals.
Thereby, although the inner diameter side is not ironed by the cored bar 202, the laminated core 1 is positioned so as to ensure concentricity (roundness on the inner diameter side). At the same time, each slot aligning arrow 203 is inserted into each slot portion 12 to correct a slight shift of the slot shape in the radial direction and the circumferential direction in each slot portion 12. The portions 12 have a predetermined slot width (U-shape) and are arranged in the circumferential direction at a regular slot pitch.

Subsequently, as step 4, as shown in FIG. 5D, the ironing ring 205 is lowered as indicated by an arrow. The ironing ring 205 is made of a super hard material, and the outer diameter side of the laminated core 1 is ironed and formed while moving (lowering) to the outer periphery on the upper end side of the work receiver 201 while sliding on the outer periphery of the work holder 204. Go.
That is, the inner diameter of the ironing ring 205 is set to be slightly smaller than the outer diameter of the laminated core 1 as a workpiece (a size corresponding to the normal core outer diameter). Accordingly, each sheet outer end side of the laminated core 1 is pushed in the inner diameter direction while being plastically deformed, and ironing is performed.
In the ironing process, a diameter reduction phenomenon occurs in which the inner and outer diameters of the laminated core 1 are reduced. First, the inner circumferential surface of the laminated core 1 is in contact with and pressed against the outer circumferential surface of the cored bar 202. As a result, the inner diameter side of the laminated core 1 is corrected, and at the same time, secondly, the side surfaces of the respective tooth portions 11 are further strongly pressed against the side surfaces of the slot aligning arrows 203, whereby the respective tooth portions 11 (slot portions 12). ) Is further corrected.

Thus, the combination of the inner diameter side cored bar 202, the slot aligning arrow 203, and the outer diameter side ironing ring 205 allows the inner and outer diameter sides of the laminated core 1 and each slot portion 12 (tooth portion 11) to have a predetermined shape and shape. It is shaped to ensure the normal position, and the ironing process for the laminated core 1 is completed.

Finally, in step 5, as shown in FIG. 5E, the ironing ring 205, the cored bar 202, the slot aligning arrow 203, and the work retainer 204 are driven in the opposite directions to release all constraints. Then, the shaped laminated core 1 is taken out as the stator core 108, and the finishing process is finished.

[Problems in the ironing process]
Although it has been considered that the stator core 108 having a desired perfect circular shape can be obtained by the series of ironing processes described above, a deformation problem occurs in the laminated core 1 in the process of the ironing process described above. It has been found.
Here, the deformation problem will be described in detail with reference to FIG.

FIG. 6 schematically illustrates a deformation event that occurs in the laminated core 1 during the ironing process in steps 3 and 4 described above, and shows a deformation region around the notch 14 (E4) of the laminated core 1. Z is generated.

The mechanism is considered to be based on the following events according to the verification of the present inventors.
(1) In step 3 shown in FIG. 5 (c), the laminated core 1 is positioned and held on the inner diameter side by the cored bar 202, and the slot portions 12 are aligned by the slot aligning arrow 203. FIG. In step 4 shown in d), a load (pressing force) in the inner diameter direction is applied to the yoke portion 13 (E3) of the laminated core 1 by ironing by the ironing ring 205.

(2) As a result, as shown in FIG. 6, the laminated core 1 is pressed and pressed by the pressing force from both sides of the inner and outer diameters as indicated by solid line arrows. In the vicinity of the notch 14 (E4), the notch 14 (E4) is located on the back side of the teeth 11 (E1), and it is assumed that the following deformation event occurred. Is done.
That is, the outer peripheral side of the notch 14 (E4) is reduced in diameter, so that the deformation acting force is transmitted from the outer diameter side to the inner diameter side of the tooth part 11, and the core metal 202 is connected to the inner diameter side of the tooth part 11. A contact reaction force (pressing force from the cored bar 202) is generated. The influence of this reaction force is greater in the former where the notch 14 is present and where the notch 14 is not. Therefore, the teeth 11 directly under the notch 14 is on the outer diameter side as indicated by the white arrow ( For example, the notch portion 14 (E4) is a two-dot chain line because the yoke portion 13 (E3) nearest to the notch portion 14 side is easily displaced (deformed) in the circumferential direction. As a result, the entire core shape (cylindrical shape) of the laminated core 1 was deformed into “bite” at four locations near the notch 14 (E4).
Thus, not only the inner and outer diameter dimensions (roundness) of the laminated core 1 are inhibited, but also the peripheral length of the laminated core 1 and the teeth (slot) arrangement interval are inhibited.

(3) In addition, as a result of the distortion of the notch 14 (E4), the tooth portion 11 (E1) adjacent to the notch 14 is displaced to the outer diameter side. As the distance increases, the fitting allowance (tightening allowance) between the slot portion 12 (E2) and the slot aligning arrow 203 tends to decrease. As a result, since the degree of correction of the teeth portion 11 and the slot portion 12 is reduced, even if the molding process is performed, the inclination of the teeth portion 11 and the slot portion 12 with respect to the normal position and the deviation in the circumferential direction cannot be corrected. The normal positions of the teeth portion 11 (E1) and the slot portion 12 (E2) themselves may be displaced easily.

[Features of Example 1]
In the present embodiment, in order to solve the above problem, in the “finishing step”, when ironing is performed on the inner and outer diameter sides of the laminated core 1, the notch 14 (E4) is changed from the outer diameter direction to the inner diameter direction. It is characterized by carrying out ironing processing while applying a pressing force.

Specifically, as shown in FIGS. 7 and 8, the shaping device 200 includes a plurality of rod-shaped support members 206 that apply a pressing force from the outer diameter direction to the inner diameter direction with respect to each notch portion 14 of the laminated core 1. The same number of notches 14 are provided.

As shown in FIG. 8B, the support member 206 has an L-shape as a whole in which the rod-like body 206b hangs down from the mounting stay portion 206a. The rod-like body 206b is formed with a projecting portion 207 having a cross-sectional shape in which the concave shape of the notch portion 14 is transferred in the axial direction (length direction). The projecting portion 207 has a uniform projecting amount over its entire length, but the upper and lower end portions 207a and 207b are formed with tapered surfaces (chamfered) in consideration of workability.

Then, as shown in FIG. 8A, the support member 206 has an axial direction in which a rod-like body 206b (projecting portion 207) is located at a predetermined position on the inner peripheral side of the ironing ring 205 (a position corresponding to the notch portion 14). Are fixed to the ironing ring 205 from above and below by the mounting plates 205a and 205b.
Therefore, the support member 206 can move up and down integrally with the ironing ring 205.

Accordingly, as shown in FIG. 7, during the ironing process (steps 3 and 4), when a pressing load is applied (clamped) from both sides of the inner and outer diameters to the laminated core 1 as indicated by solid arrows. When the protruding portion 207 of the support member 206 is fitted into the cutout portion 14, the cutout portion 14 (semicircular surface thereof) is directly directed from the outer diameter direction to the inner diameter direction as indicated by the solid white arrow. A pressing force (shaping force / correcting force) can be applied. As a result, a phenomenon such as a hollow arrow generated in FIG. 6, that is, ironing is performed while preventing the tooth portion 11 from moving (deformed) to the outer diameter side (the notch portion 14 side). Can do.
Therefore, at the time of ironing, it is possible to satisfactorily correct (shape) the teeth 11 and the slots 12 as well as the notches 14 around the notches 14 of the laminated core 1.

  According to the first embodiment described above, the following effects can be obtained in terms of manufacturing method and apparatus.

[Effects on manufacturing method]
(1) In performing the ironing process on the inner and outer diameter sides of the laminated core 1 in the finishing process, the ironing process is performed while applying a pressing force from the outer diameter direction to the inner diameter direction with respect to the notch 14 (E4). Therefore, when the pressing load is applied from both sides of the inner and outer diameters to the laminated core 1 during the ironing process, the notch 14 (semicircular surface thereof) is also directly directed from the outer diameter direction to the inner diameter direction. Thus, not only the notch part 14 but also the tooth part 11 and the slot part 12 can be corrected (shaped) well around the notch part 14.
(2) Therefore, the notch portion 14 is not crushed and the roundness is hindered, or the tooth portion 11 and the slot portion 12 are displaced with respect to the normal position, thereby causing no pitch deviation.
(3) Thus, it is possible to prevent a deformation event from occurring around the notch 14 (E4) of the laminated core 1, and to obtain the stator core 108 having a high roundness. Therefore, there is no risk of performance deterioration due to the shift of the slot pitch, and even if the storage amount of the stator coil 107 is increased or the stator coil moves due to vibration during operation, the stator coil 107 is damaged. Therefore, a high space factor and high reliability of the stator coil 107 can be secured.
(4) In the final finishing step, as described above, the notch portion 14 itself is shaped by ironing, so the following effects can be expected.
In other words, in the previous stage of the finishing process, the inner peripheral surface (semi-circular surface) of the notch 14 forms a complex uneven surface along the axial direction due to deviation of each winding layer or punching burrs in the pressing process. Therefore, it has had a considerable effect on securing the effective magnetic path area and inserting workability of the through bolt 103. On the other hand, since the inner peripheral surface (semicircular surface) of the notch 14 can also be smoothed by the above shaping, it is possible to secure a uniform effective magnetic path area over the entire length in the axial direction also at the notch 14. Thus, the workability of inserting the through bolt 103 can be improved, and it is possible to contribute to the provision of an even higher quality stator core 108.

[Effects on equipment]
(1) The shaping device 200 has a simple configuration in which a plurality of bar-shaped support members 206 are additionally provided with respect to an existing device, that is, the support members 206 are simply attached to the inside of the ironing ring 205 at predetermined intervals.
(2) In addition, each bar-like support member 206 itself has a simple configuration in which only a protruding portion 207 having a cross-sectional shape obtained by transferring the concave shape of the notch portion 14 along the axial direction (length direction) is provided. In addition, the ironing ring 205 can be assembled later.
Therefore, combined with the effect (1), the capital investment is inexpensive.
(3) Further, the plurality of support members 206 are provided, and the ironing process can be performed while reliably applying the pressing force from the outer diameter direction to the inner diameter direction with respect to each of the plurality of notches 14. .
(4) Thus, the manufacturing method of the stator core 108 of Example 1 can be realized economically and with high quality.

[Modifications; Other Examples]
Although the present invention has been described in detail with reference to one embodiment, various modifications can be made without departing from the spirit of the present invention, and such modifications will be exemplified below as other embodiments.

(1) In the first embodiment, the support member 206 is provided with the protruding portion 207 having a uniform protruding amount over the entire length. However, as this protruding portion, the protruding amount from the lower side to the upper side in the length direction is provided. By providing the taper-shaped protrusion part which increases gradually, the fitting amount to the notch part 14 can be gradually deepened from the initial stage to the latter stage of the ironing forming process (shaping process). Accordingly, the pressing force applied from the outer diameter direction to the inner diameter direction can be gradually increased with respect to each notch portion 14 of the laminated core 1 according to the progress of the ironing process, and can be smoothly shaped.

(2) In the first embodiment, the type in which the plurality of rod-shaped support members 206 are assembled to the ironing ring 205 later is illustrated. However, these support members 206 are arranged on the inner periphery of the ironing ring 205. It may be integrally formed on the surface.
However, a plurality of rod-like support members 206 can be configured as independent support member groups, like the slot aligning arrows 203, and can be moved up and down in cooperation with the ironing ring 205.

(3) The protrusion 207 formed on the support member 206 is defined as “a protrusion 207 having a cross-sectional shape obtained by transferring the recess shape of the notch 14 in the axial direction”. It is not limited only to the “projection 207 having substantially the same cross-sectional shape as the recess shape of the notch 14 over the entire length” exemplified in Example 1, but is uneven in the axial direction and the radial direction as shown in FIG. In view of the nature of shaping the notch 14 in the state of having a concave surface, including the tapered protrusion of the first modification example, “the regular dent shape of the notch 14 (the notch shape as the final product)” This is a general term for the protrusions including all the protrusions 207 "having a protrusion shape / protrusion cross-sectional area sufficient to ensure.

(4) In addition, regarding the core sheet 10, specifications on the product side, for example, the diameter (curvature) of the laminated core 1, the plate thickness and radial width of the core sheet 10, conditions on the manufacturing side, for example, bending means, etc. Of course, the present invention can be applied not only to the same plate thickness but also to a stator core of the type in which the outer peripheral edge side of the yoke portion 103 is formed into a thin portion and bent into an annular shape.

(5) Further, the notch portion 14 is not limited to the one provided on the back side of the tooth portion 11, and is provided on the back side of the slot portion 12, or the teeth portion 11 and the slot portion 12. Even if it is provided across both back sides, it can be similarly applied.

(6) Moreover, in Example 1, although the location of the said notch part 14 is effectively utilized as a welding location, as a means to fix each winding layer of the lamination | stacking core 1 at a 3rd process (sizing process). Various methods such as welding or caulking other than the notch portion 14 have been put into practical use, and of course any of them may be adopted.

(7) In the first embodiment, the slot shaping by the slot aligning arrow 203 is performed as a part of the ironing process in the finishing process. According to this, when the outer diameter of the laminated core 1 is reduced, the circumferential interval between the teeth portions 11 is reduced, and the circumferential arrangement interval between the slot aligning arrows 203 is also reduced. As a result, the teeth portions 11 (slot portions 12). The correction effect can be enhanced. As a method not expecting such an enhancement effect, there is a case where the slot aligning arrow 203 and the ironing ring 205 are completely separated and sequentially processed, for example, a case where slot shaping by the slot aligning arrow 203 is performed in a sizing process. The present invention can also be applied to the case.

(8) In the above embodiment, the case where the present invention is applied to a stator core of an automotive alternator (alternator) has been described. However, the present invention is not limited to this, and a laminated core type made of a magnetic plate as a core material is used. The present invention can be applied to a rotating electric machine having a stator core, for example, a high voltage drive motor, and achieve the same effects.

  The features and advantages of the present invention that have been described in detail above will be summarized as follows according to each means described as a dependent claim (excluding dependent claim 4) in the claims.

(Feature 1 = Means of claim 2)
In the manufacturing method of the stator iron core of the rotating electrical machine according to claim 1,
In the pressing step, the plurality of notches 14 are formed in the yoke portion 103 so as to be positioned on the back side of the teeth portion 11.
According to the above means, when the notch portion 14 is positioned on the back side of the tooth portion 11, the deformation phenomenon around the notch portion is facilitated due to the influence of the tooth portion 11 during the ironing process. Therefore, the cutout portion 14 can be formed at a location having little influence on the magnetic performance.

(Feature point 2 = Means of claim 3)
In the manufacturing method of the stator iron core of the rotary electric machine according to claim 1 or 2,
The finishing process is characterized in that the pressing force applied to the notch 14 is increased in accordance with the progress of the ironing process.
According to the above means, the pressing force applied from the outer diameter direction to the inner diameter direction can be gradually increased with respect to each notch portion 14 of the laminated core 1 in accordance with the progress of the ironing process, and can be smoothly shaped. Can do.

(Feature point 3 = Means of claim 5)
In the manufacturing apparatus of the stator iron core of the rotating electrical machine according to claim 4,
The shaping device 200 shapes the laminated core 1 while the cored bar 202, the ironing ring 205, and the support member 206 slide in the axial direction with respect to the laminated core 1.
The support member 206 is characterized by having, as the protruding portion 207, a tapered protruding portion whose protruding amount gradually increases from the initial stage to the latter stage of the shaping process.
According to the said means, the manufacturing method of Claim 3 can be implemented efficiently.

(Feature point 4 = Means of claim 6)
In the manufacturing apparatus of the stator iron core of the rotating electrical machine according to claim 4 or 5,
The plurality of support members 206 are attached to the inner peripheral surface of the ironing ring 205 so as to match the interval of the notches 14 of the laminated core 1.
According to the above means, the plurality of support members 206 can be easily assembled to the ironing ring 205 by post-assembly, and the shaping device 200 can be provided economically.

DESCRIPTION OF SYMBOLS 1 ... Laminated core, 10 ... Core sheet | seat, 11 (E1) ... Teeth part, 12 (E2) ... Slot part, 13 (E3) ... Yoke part, 14 (E4) ... Notch part, 100 ... AC generator for motor vehicles (Rotary electric machine), 106 ... stator, 107 ... stator coil, 108 ... stator iron core, 200 ... shaping device, 202 ... cored bar, 203 ... slot aligning arrow, 205 ... ironing ring, 206 ... support member, 207 ... Protrusion.

Claims (6)

Using a belt-shaped core sheet (10) made of a magnetic plate, a teeth portion constituting a plurality of magnetic poles for winding a stator coil (107) on one side in the width direction on the core sheet (10) (11, E1) and a slot (12, E2) are formed, and a yoke (13, E3) is formed on the other side in the width direction, and a plurality of notches (14, E4) are formed on the outer periphery thereof. Process,
The core sheet is laminated in a cylindrical shape while being spirally wound so that the magnetic pole is on the inner peripheral side, and the teeth portion, the slot portion, and the notch portion of each winding layer are respectively axially arranged. A winding step of aligning to form the laminated core (1);
A sizing step of cutting the laminated core for each predetermined laminated dimension and fixing each laminated layer of the laminated core so as not to shift,
A finishing step of shaping the laminated core into a desired perfect circle shape by ironing the inner and outer diameter sides of the laminated core after sizing,
In the finishing step, the iron core forming process is performed while applying a pressing force from the outer diameter direction to the inner diameter direction with respect to the plurality of notches, and the stator core (108) of the rotating electrical machine (100) Manufacturing method. In the manufacturing method of the stator iron core of the rotating electrical machine according to claim 1,
In the pressing step, a plurality of the notch portions are formed on the yoke portion so as to be positioned on the back side of the teeth portion. In the manufacturing method of the stator iron core of the rotary electric machine according to claim 1 or 2,
In the finishing step, the pressing force applied to the notch is increased in accordance with the progress of the ironing process, and the method of manufacturing a stator core of a rotating electrical machine is characterized. It is a manufacturing apparatus for enforcing the manufacturing method of the stator iron core of the rotating electrical machine according to any one of claims 1 to 3,
The shaping device (200) for executing the ironing process includes a cored bar (2002) for shaping the inner diameter side of the laminated core, an annular ironing ring (205) for shaping the outer diameter side of the laminated core, A plurality of rod-shaped support members (206) for applying a pressing force from the outer diameter direction to the inner diameter direction with respect to each notch portion of the laminated core,
The support member has a projecting portion (207) having a cross-sectional shape obtained by transferring the recess shape of the notch portion along the axial direction, and the projecting portion is the laminated core formed by the core metal and the ironing ring. An apparatus for manufacturing a stator core of a rotating electrical machine, wherein the stator core is inserted into the notch at the time of shaping. In the manufacturing apparatus of the stator iron core of the rotating electrical machine according to claim 4,
The shaping device is for shaping the laminated core while the cored bar, the ring and the support member slide in the axial direction with respect to the laminated core.
The said support member has a taper-shaped protrusion part from which the protrusion amount increases from the early stage of a shaping process to the latter stage as said protrusion part, The manufacturing apparatus of the stator core of the rotary electric machine characterized by the above-mentioned. In the manufacturing apparatus of the stator iron core of the rotating electrical machine according to claim 4 or 5,
The apparatus for manufacturing a stator core of a rotating electrical machine, wherein the plurality of support members are attached to an inner peripheral surface of the ironing ring so as to match a distance between the notches.

Images