JP5598062B2 - Manufacturing method of low iron loss rotary core - Google Patents

Description

The present invention relates to a manufacturing method for a rotary motor iron core was processed by punching a workpiece plate.

  For rotating electrical machines such as automobiles and home electric appliances, a rotating electrical machine core in which a plate material obtained by punching a processed plate material typified by an electromagnetic steel plate is laminated is often used.

  FIG. 9 is a schematic longitudinal sectional view illustrating a general punching process using a punching punch and a punching die. In FIG. 9, the code | symbol 80 is the punching apparatus which set the to-be-processed board | plate material.

  The punching device 80 has a punch 82 and a punch die 83. The workpiece 81 placed on the punching die 83 is punched by moving the punching punch 82 in the direction of the white arrow in FIG.

  FIG. 10 is a cross-sectional view in the plate thickness direction showing the processed plate 81 after punching. As shown in FIG. 10, the end surface of the punching portion 84 is processed into a sag surface 86 formed by the workpiece plate 81 being entirely pushed by the punching punch 82, and into the gap between the punching punch 82 and the punching die 83. A shearing surface 87 formed by drawing the plate material 1 and locally stretched, a fracture surface 88 formed by breaking the work plate material 81 drawn into the gap between the punch 82 and the punching die 83, and the work A burr 89 is formed on the back surface of the plate 81.

  Since the vicinity of the end surface of the punched portion 84 having the sag surface 86, the shear surface 87, and the fracture surface 88 is formed by plastic deformation, plastic strain is introduced. The plastic strain hinders the movement of the domain wall in the iron core when the rotating electric machine core is excited, and deteriorates the energy efficiency of the rotating electric machine. Such loss in the iron core when excited is hereinafter referred to as iron loss.

  As a method for improving iron loss, Patent Document 1 proposes a method of removing plastic strain by annealing a processed plate after punching.

  Patent Document 2 proposes a method of removing a region where plastic strain is introduced by punching by shaving.

  In Patent Document 3, a punched hole is not completely punched in the processed plate material, and a half punched hole is formed by punching to the middle of the plate thickness of the processed plate material. A method of forming by shaving has been proposed.

JP-A-7-298570 JP 2007-252092 A JP 2004-34143 A

  In the method proposed in Patent Document 1, the time required for the annealing process is long, and a dedicated annealing facility is required.

  In addition, the methods proposed in Patent Documents 2 and 3 cannot completely remove the vicinity of the end face of the punched portion into which plastic strain has been introduced by shaving, but also newly shaving plastic strain by shaving. There is a problem that it is introduced near the end face of the processed portion.

In view of the above-described problems of the prior art, the present invention provides a shaving process for an area where plastic strain is introduced without annealing the plastic strain introduced near the end face of the punched portion, which causes iron loss to deteriorate. and to provide a rotary electric machine iron heart of low iron loss has been removed in an advantageous production method.

  In order to achieve the above object, the present inventor has earnestly studied a method for removing plastic strain introduced in the vicinity of the end face of the punched portion by shaving.

  As a result, the plastic strain is newly introduced in the vicinity of the end face of the shaving portion by letting the deformation that occurs when shaving the vicinity of the end face of the punched portion into which the plastic strain is introduced to the shaving processing waste side. I found that it was not introduced.

  Then, when the area to be removed by one shaving process from the end face of the punching process part is set to a predetermined ratio with respect to the plate thickness of the processed plate material, the deformation that occurs when the shaving process is performed on the shaving scrap side I found out that I could escape.

  The present invention has been made based on the above findings, and the gist thereof is as follows.

(1) In a method of manufacturing a rotating electrical machine iron core that has been punched from a processed plate material made of an electromagnetic steel plate ,
The end face of the punched part is subjected to shaving twice or more, and an area corresponding to 5 to 25% of the plate thickness of the processed plate material is removed from the end face for one shaving process, and the shaving is performed twice or more. In the processing, an area corresponding to 40 to 60% of the plate thickness of the processed plate material is removed,
Further, the low-iron-loss rotating electric machine is characterized in that the shaving is performed by a shaving punch and a shaving die in which a gap between the shaving punch and the shaving die is 0 to 5% of a plate thickness of the processed plate material. Manufacturing method of iron core.

( 2 ) The method of manufacturing a rotating electrical iron core according to (1 ) , wherein the shaving process is performed with a shaving punch having a plurality of blades in a traveling direction of the shaving process and a shaving die.

( 3 ) The rotating electrical machine core according to (1) or ( 2) above, wherein a gap between a punching punch for performing the punching and a punching die is 0 to 20% of a plate thickness of the processed plate material. Manufacturing method.

  According to the present invention, a region corresponding to a predetermined ratio with respect to the plate thickness of the plate material to be processed is removed from the end face of the punched portion into which plastic strain has been introduced by shaving. A rotary electric iron core with low iron loss can be obtained without annealing the electric iron core.

  Further, according to the present invention, in the stator core and the rotor core used in the same rotating electric machine, the size of the stator core is larger than the size of the rotor core, and therefore, the punching portion Even in the case of a stator core having a long end face circumference and a large amount of plastic strain introduced near the end face of the punched portion, the plastic strain can be reliably removed. Iron loss can be significantly improved.

  By laminating the low iron loss rotary electric machine core of the present invention, a low iron loss rotary electric machine laminated core can be obtained.

It is a top view which shows the to-be-processed board | plate material which investigated the area | region which is work-hardened about the internal peripheral surface vicinity of the punching hole in which the plastic strain was introduce | transduced. It is a longitudinal cross-sectional schematic diagram which shows a state when the internal peripheral surface of a punching hole is removed by the shaving process. It is a longitudinal cross-sectional view which shows the result of having calculated | required the deformation | transformation state of the to-be-processed board | plate material when shaving the inner peripheral surface of a punching hole by numerical analysis. In FIG. 3A, when the region to be removed by shaving is 20% of the plate thickness of the processed plate material, FIG. 3B is to have the region to be removed by shaving processed 40% of the plate thickness of the processed plate material. Show the time. It is a longitudinal cross-sectional view which shows the principal part of the shaving punch which has two blades in the advancing direction of shaving processing. It is a top view which shows the intermediate product in each process of the manufacturing method which leaves the four anchoring parts and performs a punching process and extracts four anchoring parts by the 2nd shaving process. FIG. 5 (a) is a plate material preparation process, FIG. 5 (b) is after the punching process, FIG. 5 (c) is after the first shaving process, and (d) is performed simultaneously with the second shaving process. It shows after a tether part extraction process. The state of the rotating electrical machine core intermediate product in the cross section taken along the line I-I shown in FIG. 5 (c) when the rotating electrical machine core intermediate product anchored to the workpiece plate at the anchoring portion is removed by shaving. It is a longitudinal cross-sectional schematic diagram shown. It is a top view which shows an example of the stator iron core and rotor machine iron core which are used for the same rotary electric machine. FIG. 7A shows a stator core, and FIG. 7B shows a rotor core. It is a graph which shows the iron loss improvement result when giving the shaving process to the end surface of the punching process part in the Example of this invention. It is a longitudinal cross-sectional schematic diagram explaining the general punching process by a punch and a punch die. It is board | plate thickness direction sectional drawing which shows the to-be-processed board | plate material after a punching process.

  Embodiments of the present invention will be described with reference to the drawings, together with the results of experiments and numerical analysis performed to complete the present invention.

(First embodiment of the present invention)
First, the inventor investigated the region where plastic strain was introduced and the work was hardened in the vicinity of the inner peripheral surface of a punched hole formed by punching a workpiece.

  FIG. 1 is a plan view showing a plate material to be processed in which a region where work hardening is performed in the vicinity of the inner peripheral surface of a punching hole into which plastic strain has been introduced is examined. In FIG. 1, the code | symbol 81 is a processed board material. The processed plate material 81 is generally an electromagnetic steel plate, but is not limited thereto. For example, an iron-based ferromagnetic metal plate other than the electromagnetic steel plate or a non-ferrous ferromagnetic metal plate may be used.

  The to-be-processed board | plate material 81 has the punching hole 10 formed by the punching process. As shown in FIG. 1, the processed plate material 81 has an inner peripheral surface 12 and an outer peripheral surface 52. In this investigation, the vicinity of the inner peripheral surface 12 was investigated.

  As a result of the investigation, a direction perpendicular to the punching direction of the inner peripheral surface 12 of the punching hole 10 when the gap between the punching punch and the punching die at the time of punching is within a range in which the punching hole 10 is normally punched. Of these regions, it was found that a region of 50 to 60% of the plate thickness of the processed plate material was work-hardened.

  Of the work hardened region, regions corresponding to 50%, 30%, 25%, and 10% of the plate thickness of the processed plate material were removed by one shaving process in the same direction as the punching direction.

  FIG. 2 is a schematic longitudinal sectional view showing a state when the inner peripheral surface 12 of the punching hole 10 formed by punching the workpiece 81 is removed by shaving.

  A plate material t having a thickness t and having a punching hole 10 placed on the die 3 is shaved by the shaving punch 2 being pushed down in the direction of the white arrow in FIG. . The broken line in FIG. 2 shows the shape of the punching hole 10 before being shaved.

  The shaving direction in FIG. 2 is the same as the punching direction, but the direction opposite to the punching direction, that is, the shaving process from the burr 89 (see FIG. 10) side toward the sag surface 86 (see FIG. 10). May be.

In the present invention, as shown in FIG. 2, the region indicated by _ts in the direction perpendicular to the punching direction (the direction of the white arrow in FIG. 2) from the inner peripheral surface 12 of the punching hole 10 is It was removed by shaving. In FIG. 2, a portion indicated by reference numeral 14 is a shaving hole. Although the shaving hole 14 has a shaving surface 16 and a sag surface 18, the shaving surface 16 includes the sag surface 18 unless otherwise specified in the following description.

t _s is the distance between the inner circumferential surface 12 and the shaving surface 16, corresponding to the shaving allowance of a single shaving. Also, _{t s,} as described above, 50% of the thickness of the processed plate material 81, 30%, 25%, since 10%, respectively, 0.5 t, 0.3 t, 0.25t, 0. 1t.

  Then, after the shaving process, a work-hardened region in the vicinity of the shaving surface 16 of the rotating electrical iron core 1 was investigated.

As a result, when the t _s 50% and 30% of the thickness of the processed sheet material 81, in both cases, of the vertical direction of a region with respect to the punching direction from shaving surface 16, the processed plate material 81 It was found that the work hardening occurred in a region corresponding to about 50% of the plate thickness.

  As described above, the work-hardened area in the state of the punching process is the thickness of the work plate 81 in the area perpendicular to the punching direction from the inner peripheral surface 12 of the punching hole 10. Therefore, it can be said that the size of the work-hardened region has hardly changed before and after the shaving process.

Meanwhile, when the t _s and 25% of the thickness of the processed plate material 81, of the vertical direction of a region with respect to the punching direction from shaving surface 16, corresponding to about 25% of the thickness of the processed plate material 81 It was found that the work hardened in the area to be. This value of 25% coincides with a value obtained by subtracting 25%, which is a work-hardened region after shaving, from 50%, which is a work-hardened region in the state of punching.

Further, when the t _s 10% of the thickness of the processed plate material 81, of the vertical direction of a region with respect to the punching direction from shaving surface 16, corresponding to about 40% of the thickness of the processed plate material 81 It was found that the work hardened in the area to be. This value of 40% coincides with a value obtained by subtracting 10%, which is a work-hardened region after shaving, from 50%, which is a work-hardened region in the state of being punched.

If t _s is 50% and 30%, unlike the case of 25% and 10%, the size of the area that work hardening, before and after the shaving, the reason why almost no change was verified by numerical analysis .

FIG. 3 is a longitudinal sectional view showing the result of numerical analysis of the deformation state of the processed plate 81 when the inner peripheral surface 12 of the punched hole 10 formed by punching the processed plate 81 is shaved. FIG. 3 (a) is when 20% of the thickness of the processed sheet 81 to _{t s,} FIG. 3 (b) shows a case where the _{t s} and 40% of the thickness of the processed plate material 81. In FIG. 3, a region where the equivalent plastic strain amount is 0.37 or more is defined as the high deformation portion 31. The equivalent plastic strain is expressed by the following equation (1).

FIGS. 3 (a) and 3 (b) As is apparent from, compared to _{t s} when 40% of the thickness of the processed plate material 81 (see FIG. 3 (b)), the work of _{t s} When the thickness of the plate 81 is set to 20% (see FIG. 3A), the high deformation portion 31 protrudes greatly toward the shaving waste 33.

Therefore, when the t _s and 20% of the thickness of the processed plate material 81, the deformation is escaping towards the shaving debris 33, mostly plastic strain in a region where the shaving surface 16 (see FIG. 2) As a result, it is possible to remove the plastic strain introduced in the vicinity of the inner peripheral surface 12 of the punching hole 10 during the punching process.

In contrast, when the t _s and 40% of the thickness of the processed plate material 81, the deformation does not escape towards the shaving debris 33, in a region to be a shaving surface 16 (see FIG. 2), FIG. The plastic strain indicated by the black arrow in 3 (b) is introduced.

That is, when the t _s and 40% of the thickness of the processed sheet material 81, while removing regions that are work hardened near the inner circumferential surface 12 of the punched holes 10 in shaving, shaving surface 16 This is the same as the plastic strain introduced in the vicinity of the inner peripheral surface 12 of the punching hole 10 cannot be removed.

Based on the above numerical analysis results, the results of an experiment by the t _s while varying the t _s when 25% or less of the plate thickness of the workpiece plate 81 is caused to be processed plate material 81 during shaving deformation However, the plastic strain introduced into the inner peripheral surface 12 of the punching hole 10 can be removed without newly introducing plastic strain in the vicinity of the shaving processed surface 16.

Therefore, the upper limit of t _s, it is necessary to be 25% of the thickness of the processed plate material 81. On the other hand, if t _s is less than 5% of the thickness of the processed plate material 81, removal of areas which plastic strain is introduced by punching it is very low, the magnetic flux of disturbance by removing the plastic strain prevention since the effect is very small to be, t _s is required to be 5% or more of the thickness of the processed plate material 81.

Then, if t _s is a shaving machining allowance in a single shaving is in the range of 5-25% of the thickness of the processed plate material 81 by performing the shaving operation more than once, the punched hole 10 More plastic strain introduced in the vicinity of the inner peripheral surface 12 can be removed.

  However, the region where the plastic strain is introduced in the vicinity of the inner peripheral surface 12 of the punching hole 10 is the plate of the work plate 81 in the region perpendicular to the punching direction from the inner peripheral surface 12 of the punching hole 10. Since the region is 50 to 60% of the thickness, when the shaving process is performed twice or more, the sum of the areas removed by the shaving process is determined from the inner peripheral surface 12 of the punching hole inner peripheral part 10 with respect to the punching direction. Even if it exceeds 60% of the region in the vertical direction, there is no region where the plastic strain to be removed is introduced. Accordingly, the effect of preventing the magnetic flux disturbance by removing the plastic strain is saturated.

For example, when the t _s and 20% of the thickness of the workpiece plate 81 until the number of shaving three times, in accordance with overlapping times, the effect of preventing the magnetic flux of the disturbance due to plastic distortion removal is increased.

  However, the region corresponding to 60% of the plate thickness of the plate 81 to be processed, which is work-hardened in the direction perpendicular to the punching direction from the inner peripheral surface 12 of the punching hole 10 by three shavings, is removed. (20% / time × 3 times = 60%) Therefore, even if the shaving process is performed four times or more, the effect of preventing the disturbance of the magnetic flux by removing the plastic strain is saturated.

  On the other hand, if the sum of the regions in the direction perpendicular to the punching direction of the inner peripheral surface 12 of the punching hole 10 removed by the shaving process twice or more is less than 40%, the work-hardened region is sufficiently removed. Not.

  Therefore, the sum of the regions in the direction perpendicular to the punching direction from the inner peripheral surface 12 of the punching hole 10 removed by the shaving process twice or more is a region corresponding to 40 to 60% of the plate thickness of the plate material 81 to be processed. It is preferable that

Incidentally, in the region of the inner peripheral surface 12 of the punching holes 10, when performing shaving of at least twice, in shaving the first time, the inner peripheral surface 12 of the punched hole 10, since it is larger by t _s , the shaving punch used for shaving the second it is of course to be as large as t _s.

  The gap (clearance) between the shaving punch 2 and the shaving die 3 is preferably in the range of 0 to 20% of the plate thickness of the plate 81 to be processed. When the gap between the shaving punch 2 and the shaving die 3 is negative (the outer peripheral surface of the shaving punch 2 is larger than the inner peripheral surface of the shaving die 3 in a plane perpendicular to the shaving processing direction) The shaving die 3 is heavily worn and its life is remarkably short.

On the other hand, when the gap between the shaving punch 2 and the shaving die 3 exceeds 25% of the plate thickness of the work plate 81, a slight plastic strain is introduced at the end of the shaving process, which was introduced during the punching process. The effect of removing plastic strain by shaving is reduced. Therefore, the upper limit value of the gap between the shaving punch 2 and the shaving punch 3 is preferably 25%. In the present invention, the upper limit value is defined as 5%, which is confirmed in Examples described later.

  The gap between the shaving punch 2 and the shaving die 3 is the distance (one side) between the outer peripheral surface of the shaving punch 2 and the inner peripheral surface of the shaving die. For example, when the shaving hole 10 is a circle, it is the difference between the radius of the inner peripheral surface of the shaving die 3 and the radius of the outer peripheral surface of the shaving punch 2 in a plane perpendicular to the shaving direction.

  In addition, 0% of the thickness of the workpiece plate 81 between the shaving punch 2 and the shaving die 3 means that there is no gap between the shaving punch 2 and the shaving die 3.

  In addition, the gap between the punch 82 and the punch die 83 is preferably in the range of 0 to 20% of the plate thickness of the workpiece plate 81. When the gap between the punch 82 and the punch die 83 is negative (in the plane perpendicular to the punching direction, the outer peripheral surface of the punch 82 is larger than the inner peripheral surface of the punch die 83), The punching die 83 is heavily worn and its life is remarkably short.

  On the other hand, when the gap (clearance) between the punch 82 and the punch die 83 exceeds 20% of the plate thickness of the processed plate 81, a region where plastic strain is introduced near the inner peripheral surface 12 of the punch hole 10 is large. Therefore, the area to be shaved becomes large.

Then, as described above, removal region by shaving the per, i.e. t _s is required to be 5 to 25% of the thickness of the processed plate material 81. Therefore, when the area to be shaved becomes large, it is necessary to greatly increase the number of shaving processes in order to remove all the areas where plastic strain is introduced, leading to an increase in the manufacturing cost of the rotating electrical iron core.

  In addition, the gap between the punch 82 and the punch die 83 is 0% of the plate thickness of the processed plate 81. This means that there is no gap between the punch 2 and the punch die 3.

  The rotary electric machine core 1 according to the first embodiment of the present invention obtained in this way exhibits a lower iron loss value than the rotary electric machine core that is obtained by punching the plate material to be processed.

  And the rotary electric machine laminated iron core comprised by laminating | stacking the rotary electric machine core 1 which concerns on 1st Embodiment of this invention is from the rotary electric machine laminated iron core comprised by laminating | stacking the rotary electric machine core which has punched the to-be-processed board | plate material. Also shows a low iron loss value.

  In the first embodiment of the present invention, as shown in FIG. 1, the case where the inner peripheral surface 12 of the punching hole 10 is used as the end surface of the punching processing portion has been described. If the outer peripheral surface 52 is used as the end surface of the punched portion, the region corresponding to 5 to 25% of the plate thickness of the processed plate material is removed from the outer peripheral surface 52 by one shaving process. By doing this, the same action and effect as when removing a region corresponding to 5 to 25% of the plate thickness of the processed plate material from the inner peripheral surface 12 of the punching hole 10 by one time by shaving is obtained. Can do.

(Second embodiment of the present invention)
Two or more shaving processes can be performed with one shaving punch. FIG. 4 is a longitudinal sectional view showing a main part of a shaving punch having two blades in the advancing direction of the shaving process. In FIG. 4, reference numeral 60 denotes a two-stage shaving punch.

  The two-stage shaving punch 60 has shaving blades 62 and 63. The shaving punch 60 moves toward the die (not shown) from the shaving blade 63 toward the shaving blade 62 (from the top to the bottom in FIG. 4).

  The shaving blade 62 performs the first shaving process, and the shaving blade 63 performs the second shaving process.

  The two-stage shaving punch 60 has a diverging surface 64 that extends from the shaving blade 63 side to the shaving blade 62 side between the shaving blade 62 and the shaving blade 63. At the time of the second shaving process, the shaving scraps can be released to the space formed by the diverging surface 64, so that no plastic strain is applied to the area that becomes the second shaving surface, as shown in FIG. The same effect as the normal shaving punch 2 can be obtained.

  If the two-stage shaving punch has the shape indicated by the thick broken line in FIG. 4, the shaving scraps generated by the second shaving process are the surface indicated by the thick broken line, and the surface to be shaved from now on. A plastic strain is introduced into a region that becomes a shaving surface after the second shaving.

  As described above, the region to be removed by one shaving process needs to be 5 to 25% of the plate thickness of the processed plate material 81. Therefore, the difference between the dimension D and the dimension C in FIG. 4 needs to be 0.1 to 25% of the plate thickness of the processed plate material 81.

  In addition, although 2nd Embodiment demonstrated the case where there were two shaving blades, it is not restricted to this. When the number of shaving blades is 3 or more, it is preferable that all the shaving blades satisfy the above gap conditions. Therefore, on the surface perpendicular to the shaving process direction, the difference in the distance (one side) between the outer peripheral surface of the shaving punch having a plurality of blades and the outermost surface of the minimum blade is 5 to 20% of the plate thickness of the plate 81 to be processed. It is preferable.

  The rotary electric machine core 1 according to the second embodiment of the present invention thus obtained has a lower iron loss value than that of the rotary electric machine core that is obtained by punching the workpiece material.

  And the rotary electric machine laminated iron core comprised by laminating | stacking the rotary electric machine core 1 which concerns on 2nd Embodiment of this invention is from the rotary electric machine laminated iron core comprised by laminating | stacking the rotary electric machine core with which the to-be-processed plate material was punched and processed. Also shows a low iron loss value.

(Third embodiment of the present invention)
It is also possible to perform a punching process while leaving at least one anchoring portion in the punching process of the workpiece plate material, and to remove all the anchoring portions in the final shaving process, thereby obtaining a rotating electrical iron core.

  FIG. 5 is a plan view showing an intermediate product in each step of the manufacturing method in which the punching process is performed leaving the four anchoring parts and the four anchoring parts are removed by the second shaving process. FIG. 5 (a) shows the plate material preparation process, FIG. 5 (b) shows the punching process, FIG. 5 (c) shows the first shaving process, and FIG. 5 (d) shows the second shaving process. It shows after the tether part removing step performed simultaneously.

  As shown in FIG. 5A, the workpiece plate 81 is placed on a punching die (not shown) to prepare for punching.

  As shown in FIG. 5B, the four anchoring portions 70a, 70b, 70c, and 70d are left, and the punching grooves 71a, 71b, 71c, and 71d are punched out. The rotating electrical machine core intermediate product 73 is anchored to the workpiece plate 81 by the anchoring portions 70a to 70d. In the present embodiment, the number of tethers is four, but the number of tethers is not limited to four as long as the rotating electrical machine core intermediate product 73 can be tethered to the workpiece plate 81.

As shown in FIG. 5C, the first shaving process is performed on the punching end faces 72a, 72b, 72c, and 72d of the rotary electric machine core intermediate product 73. _{T s} is a shaving allowance is 5 to 25% of the thickness of the processed plate material 81. In FIG. 5C, the broken lines indicate the punching end faces 72a to 72d of the rotary electric machine core intermediate product 73 before the first shaving process.

Next, the shaving process surfaces 74a, 74b, 74c, and 74d are subjected to the second shaving process, and at the same time, the anchoring portions 70a to 70d are removed to obtain the rotating electrical machine core 1 shown in FIG. T _s in the second shaving as well, similar to the shaving process the first time, 5 to 25% of the thickness of the processed plate material 81.

  In the present embodiment, the shaving process is performed twice, but may be performed three or more times. In that case, the anchoring portions 70a to 70d are removed during the last shaving process. For example, when the shaving process is performed four times, the tethers 70a to 70d are removed simultaneously with the fourth shaving process.

  Thus, in the third embodiment of the present invention, the rotary electric machine core intermediate product 73 is anchored to the work plate 81 until the rotary electric machine core 1 is obtained. From the punching of the work plate 81, the rotary electric machine The process until the iron core 1 is obtained can be a progressive process. When a plurality of rotating electrical machine cores 1 are obtained from a single plate material 81, each rotating electrical machine core 1 is not separated and is particularly useful for reducing the number of manufacturing steps of the rotating electrical machine core 1.

  Next, the state of the rotating electrical machine core intermediate product 73 when the shaving process and the tethering part are removed simultaneously will be described. FIG. 6 is a cross-sectional view taken along the line I-I shown in FIG. 5C when the rotating electrical machine core intermediate product 73 anchored to the workpiece plate 81 at the anchoring portions 70a to 70d is removed by shaving. It is a longitudinal cross-sectional view which shows the state of the rotary electric machine core intermediate product 73 in the vertical section shown by.

  The processed plate material 81 to which the rotating electrical core intermediate product 73 is anchored is placed on the shaving die 3, and the shaving punch 2 is pushed down in the direction of the white arrow in FIG. The shaving process surfaces 74a to 74d, which are surfaces, are subjected to the second shaving process while discharging the shaving waste 75, and at the same time, the anchoring portions 70a to 70d (see FIGS. 5B and 5C). It is pulled out.

As shown in FIG. 6, when shaving processed surfaces 74 a to 74 d that are outer peripheral surfaces of the rotating electrical iron core intermediate product 73, in a direction opposite to the advancing direction of the shaving punch 2 (upward in FIG. 6). While shaving debris 75 is gradually discharged, once the t _s a shaving machining allowance, when 5 to 25% of the thickness of the workpiece plate 81, deformation shaving debris 75 side generated during shaving Therefore, plastic strain is not introduced into the region that becomes the outer peripheral surface 76 of the rotating electrical machine core 1.

  In addition, since the rotating electrical machine core 1 becomes the rotating electrical machine core 1 without removing the plastic distortion introduced at the time of the portion where the anchoring portions 70a to 70d existed in the outer peripheral surface 76 thereof. From the viewpoint of preventing deterioration of the iron loss, it is preferable to make the size of the anchoring portions 70a to 70d as small as possible within a range in which the anchoring of the rotating electrical iron core 1 to the work plate 81 is not hindered.

  The rotary electric machine core 1 according to the third embodiment of the present invention obtained in this manner exhibits a lower iron loss value than the rotary electric machine core that is obtained by punching the workpiece material.

  And the rotating electrical machine laminated core comprised by laminating | stacking the rotating electrical machine core 1 which concerns on 3rd Embodiment of this invention is from the rotating electrical machine laminated iron core comprised by laminating | stacking the rotating electrical machine core which has punched the to-be-processed board | plate material. Also shows a low iron loss value.

(Fourth embodiment of the present invention)
The present invention can be applied to the rotary electric machine core 1 having various shapes as long as it can be formed by punching.

  FIG. 7 is a plan view showing an example of a stator core and a rotor core used in the same rotating electrical machine according to the fourth embodiment of the present invention. FIG. 7A shows a stator core, and FIG. 7B shows a rotor core.

The stator core 77 is manufactured by performing a shaving process once or twice on both the inner peripheral surface 12 and the outer peripheral surface 52 after being punched into the shape shown in FIG. The shaving allowance t _s per shaving and the sum of the shaving allowance are as described above. The same applies to the rotor core 78 shown in FIG.

  In the rotating electrical machine, the stator core 77 is arranged so as to surround the rotor core 78, and therefore the size of the stator core 77 used in the same rotating electrical machine is larger than the size of the rotor core 78. . Therefore, the circumferential length of the end face of the punched portion is longer in the stator core 77, and therefore the total amount of plastic strain introduced during the punching is larger in the stator core 77. Therefore, the iron loss improvement effect by removing plastic strain is greater in the stator core 77 than in the rotor core 78.

  Next, the present invention will be further described with reference to examples. Conditions in the examples are one example of conditions adopted to confirm the feasibility and effects of the present invention, and the present invention is examples of these one condition. It is not limited to. The present invention can adopt various conditions as long as the object of the present invention is achieved without departing from the gist of the present invention.

  Five types (No. 1 to No. 5) of ring-shaped iron cores each having a through hole having a diameter of 33 mm in the center of a disk having a diameter of 45 mm were manufactured by the following procedure.

  These No. 1-No. In FIG. 1, the ring-shaped iron core 5 is a ring-shaped iron core in which the inner peripheral surface 12 and the outer peripheral surface 52 are in a concentric relationship with A being 45 mm and B being 33 mm. .5 mm electrical steel sheet.

  Hereinafter, no. 1-No. For each 5, a method for manufacturing a ring-shaped iron core will be described.

(No. 1)
A through-hole having a diameter of 33 mm was formed in the center of the disk by punching to produce a ring-shaped iron core that was left as punched. The gap between the punch and the punch die was 0.025 mm (5% of the thickness of the electromagnetic steel sheet).

(No. 2)
A through-hole with a diameter of 32.6 mm was formed in the center of the disk by punching, and then a shaving punch with an outer diameter of 33 mm was performed once in the same direction as the punching to produce a ring-shaped iron core. . That is, no. Reference numeral 2 denotes a ring-shaped iron core in which a region corresponding to 40% of the thickness of the electromagnetic steel sheet is removed from the inner peripheral surface 12 by one shaving process. The gap between the punch and the punch die was 0.025 mm (5% of the thickness of the electromagnetic steel sheet). The gap between the shaving punch and the shaving die was 0.025 mm (5% of the thickness of the electromagnetic steel sheet).

(No. 3)
No. 1 except that the first shaving process was performed with a shaving punch having an outer diameter of 32.8 mm, and then the second shaving process was performed with a shaving punch having an outer diameter of 33.0 mm. A ring-shaped iron core was produced in the same manner as in 2.

  That is, no. No. 3, after the punching process, a shaving process for removing an area corresponding to 20% of the thickness of the electromagnetic steel sheet from the inner peripheral surface 12 is performed twice, and the inner peripheral surface is obtained by the two shaving processes. 12 is a ring-shaped iron core from which a region corresponding to 40% of the thickness of the electromagnetic steel sheet is removed.

  Note that the first and second shaving processes differ between the first and second shaving processes so that the gap between the shaving punch and the shaving die is 0.025 mm (5% of the thickness of the electromagnetic steel sheet). A shaving die was used.

(No. 4)
After punching, No. 2 was performed except that the two-stage shaving punch 60 shown in FIG. A ring-shaped iron core was produced in the same manner as in 3. In FIG. 4, C = 16.4 mm, D = 16.5 mm, E = 0.3 mm, F = 0.4 mm, G = 0.1 mm, and H = 16.3 mm. That is, the first shaving was performed with the shaving blade 62 having an outer diameter of 32.8 mm, and the second shaving process was performed with the shaving blade 63 having an outer diameter of 33.0 mm.

  That is, no. No. 4, after the punching process, a shaving process for removing an area corresponding to 20% of the thickness of the electromagnetic steel sheet from the inner peripheral surface 12 is performed twice, and the inner peripheral surface is obtained by the two shaving processes. No. 12 in that a region corresponding to 40% of the thickness of the electromagnetic steel sheet was removed. 3 is the same.

  However, since the two shaving processes are performed with one two-stage shaving punch 60, the same shaving die was used in the first and second shaving processes. Accordingly, the gap between the shaving punch (shaving blade 62) and the shaving die in the first shaving process is 0.125 mm (25% of the thickness of the electromagnetic steel sheet), and the shaving punch (shaving blade 63 in the second shaving process). ) And the shaving die was 0.025 mm (5% of the thickness of the electromagnetic steel sheet).

(No. 5)
A through-hole with a diameter of 32.8 mm was provided in the center of the disk by punching, and then a shaving punch with a shaving punch with an outer diameter of 33 mm was performed once in the same direction as the punching to produce a ring-shaped iron core. .

  That is, no. Reference numeral 5 denotes a ring-shaped iron core in which a region corresponding to 20% of the thickness of the electromagnetic steel sheet is removed from the inner peripheral surface 12 only once by shaving. The gap between the punch and the punch die was 0.025 mm (5% of the thickness of the electromagnetic steel sheet). The gap between the shaving punch and the shaving die was 0.025 mm (5% of the thickness of the electromagnetic steel sheet).

  No. produced as described above. The iron loss was measured when a ring-shaped laminated iron core in which five ring-shaped iron cores of 1 were laminated to 1T at 400 Hz. No. 2-No. The same applies to 5. The iron loss was measured by a method based on JIS C2550.

The results are shown in FIG. No. as an example of the present invention. 3-No. No. 4 is a punched No. 4 Compared to 1, it was confirmed that the iron loss value was extremely excellent.

  In addition, the removal area per one time was made 5 to 25% of the thickness of the electromagnetic steel sheet, and the shaving process was performed only once. No. 5, which was shaved twice. 3 and no. It was confirmed that No. 4 had a greater effect of improving iron loss.

  And after making the removal area | region per time into 5 to 25% of the plate | board thickness of an electromagnetic steel plate, it shaved twice, No. 3 and no. In No. 4, for both the first and second shaving processes, the gap between the shaving punch and the shaving die was set to 0.025 mm (5% of the thickness of the electromagnetic steel sheet). 3 confirmed that the iron loss improvement effect was higher.

  Even in the case where the removal area per time is 5 to 25% of the thickness of the electromagnetic steel sheet, plastic strain is introduced to the end face of the shaving process although it is very slight. In general, the smaller the gap between the shaving punch and the shaving die, the smaller the plastic strain introduced into the end face of the shaving process, but the same applies to this very slight plastic strain. No. In No. 3, the gap between the shaving punch and the shaving die during the first shaving processing is No. 3. (No. 3 has a gap of 5% for both times, No. 4 has a gap of 25% for the first time and 5% for the second time), so plastic strain introduced into the shaving end face The amount is even smaller. As a result, no. No. 4 compared to No. 4 No. 3 has a higher iron loss improvement effect. Therefore, as described above, the gap between the shaving die punch and the shaving die is preferably in the range of 0 to 25% of the thickness of the electromagnetic steel sheet.

  On the other hand, a region corresponding to 40% of the thickness of the electromagnetic steel sheet was removed by a single shaving process. No. 2 is a punched No. 2. Compared to 1, it was confirmed that the iron loss value was only somewhat improved.

  In addition, the place mentioned above is only what illustrated embodiment of this invention, and this invention can add a various change within the description range of a claim.

  As described above, according to the present invention, a region corresponding to a predetermined ratio with respect to the plate thickness of the plate material to be processed is removed from the end surface of the punched portion into which plastic strain has been introduced by shaving. By doing so, a rotating iron core with low iron loss can be obtained. The present invention has high utility value industrially.

  Further, according to the present invention, in the stator core and the rotor core used in the same rotating electric machine, the size of the stator core is larger than the size of the rotor core, and therefore, the punching portion Even in the case of a stator core having a long circumference and a large amount of plastic strain introduced near the end face of the punched portion of the work piece, plastic strain can be reliably removed. By applying the present invention only to the stator core in which the deterioration of the iron loss due to the above is particularly significant, it is possible to obtain a rotating electrical machine core having a good balance between manufacturing cost and iron loss improvement. The present invention has high utility value industrially.

  According to the present invention, since plastic strain introduced into the processed plate material can be removed without subjecting the processed plate material after punching to a long-time annealing, a significant increase in manufacturing cost is achieved. In this case, a rotating electrical machine core excellent in iron loss can be obtained, and this has a significant industrial effect.

1 Rotating electrical iron core 2 Shaving punch 3 Shaving die 10 Punching hole (Punching end)
12 Inner peripheral surface (Punching end surface)
14 Shaving hole 16 Shaving surface 18 Sag surface 31 High deformation part 33 Shaving scraps 52 Outer peripheral surface (Punching end surface)
60 Two-stage shaving punch 62, 63 Shaving blade 64 End spreading surface 70a, 70b, 70c, 70d Anchoring portion 71a, 71b, 71c, 71d Punching groove 72a, 72b, 72c, 72d Punching end surface 73 Rotating electric iron core intermediate product 74a, 74b , 74c, 74d Shaving processing surface 75 Shaving processing scrap 77 Stator core 78 Rotor core 80 Punching device with processing plate material 81 Processing plate material 82 Punching punch 83 Punching die 84 Punching end 86 Sag surface 87 Shear surface 88 fracture surfaces t _s 1 times in the region to be removed by shaving

Claims (3)

In a method of manufacturing a rotating electrical machine core processed by punching a processed plate material made of an electromagnetic steel plate ,
The end face of the punched part is subjected to shaving twice or more, and an area corresponding to 5 to 25% of the plate thickness of the processed plate material is removed from the end face for one shaving process, and the shaving is performed twice or more. In the processing, an area corresponding to 40 to 60% of the plate thickness of the processed plate material is removed,
Further, the low-iron-loss rotating electric machine is characterized in that the shaving is performed by a shaving punch and a shaving die in which a gap between the shaving punch and the shaving die is 0 to 5% of a plate thickness of the processed plate material. Manufacturing method of iron core. Wherein the shaving method of a rotating electric machine core according to claim 1, wherein the shaving punch having a plurality of blades in the traveling direction of the shaving, to do with the shaving die. 3. The method of manufacturing a rotating electrical machine core according to claim 1, wherein a gap between a punching punch for performing the punching and a punching die is 0 to 20% of a plate thickness of the processed plate material.

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