JP2016092949A - Punching method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a punching method capable of punching a plurality of steel plates simultaneously with sufficiently high accuracy, while reducing the material cost sufficiently.SOLUTION: A punching method includes (a) a step for preparing a tape roll of at least two magnetic steel sheets, (b) a step for supplying a processed plate composed of at least two magnetic steel sheets fixed each other, in a state pulled out from respective tape rolls and superimposed, and (c) a step for punching the processed plate in a mold. Widths of two magnetic steel sheets constituting two tape rolls are different from each other.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a method for punching a processed plate made of a plurality of steel plates.

  A laminated iron core is a component of a motor, and is formed by stacking a plurality of electromagnetic steel sheets processed into a predetermined shape and fastening them. The motor includes a rotor (rotor) and a stator (stator) made of laminated iron cores, and is completed through a process of winding a coil around the stator, a process of attaching a shaft to the rotor, and the like. A motor employing a laminated core is conventionally used as a drive source for a refrigerator, an air conditioner, a hard disk drive, an electric tool, and the like, and in recent years is also used as a drive source for a hybrid car.

  In recent years, in order to improve the magnetic characteristics of the laminated iron core and thereby improve the efficiency of the motor, a thin electromagnetic steel sheet is used as compared with the conventional one. Along with this, the number of electromagnetic steel sheets used for one laminated iron core tends to increase. Since the electrical steel sheets constituting the laminated iron core are usually manufactured by punching, there is a problem that when the number of the steel sheets increases, the number of times of punching increases, thereby reducing productivity. As means for solving this problem, Patent Document 1 discloses that a plurality of steel plates are simultaneously punched.

JP 2001-16832 A

  By the way, in order to continuously obtain an electromagnetic steel sheet having a predetermined shape by punching, the electromagnetic steel sheet (worked plate) drawn from the wound body is moved intermittently in the progressive die and opened at a predetermined position. It is necessary to provide. If the work of feeding the work plate in the progressive die is not performed accurately, the shapes of the plurality of punched magnetic steel sheets will vary, leading to a deterioration in the magnetic properties of the laminated iron core formed by laminating them.

  In order to prevent the above problems, in the conventional punching method, a certain level of strength is given to the processed plate so that the work of feeding the processed plate can be performed appropriately. That is, the strength of the plate to be processed is ensured by using an electromagnetic steel plate having an excessively wide width compared to the size of the product. For this reason, there are many portions (called “skeletons”) that remain as products on the processed plate after punching. The fact that there are many parts that do not become products in the processed plate means that there is a lot of material loss, and the conventional punching method has room for improvement in this respect.

  The present invention has been made in view of the above situation, and an object of the present invention is to provide a punching method capable of simultaneously punching a plurality of electromagnetic steel sheets with sufficiently high accuracy and sufficiently reducing material costs.

  The punching method according to the present invention includes (a) a step of preparing a wound body of at least two electromagnetic steel sheets, and (b) at least two sheets that are pulled out from each of the wound bodies and fixed to each other in an overlapped state. A step of supplying a work plate made of electromagnetic steel sheets to a mold; and (c) a step of punching the work plates in the mold, and the width of two magnetic steel sheets constituting two wound bodies is Different from each other.

  According to the study by the present inventors, when punching is performed on a processed plate in which at least two electromagnetic steel plates are laminated, all the electromagnetic steel plates constituting the processed plate are compared with the product size. It is not necessary for the width to be excessively wide, as long as the strength of the entire processed plate is maintained by at least one electromagnetic steel plate. As described above, by configuring the work plate with a plurality of electromagnetic steel plates having different widths, the strength of the entire work plate is ensured by a wide electromagnetic steel plate, while using a narrow magnetic steel plate Material that is not a product can be reduced. That is, according to the punching method, a plurality of electromagnetic steel sheets can be punched simultaneously with sufficiently high accuracy, and the material cost can be sufficiently reduced.

  In the punching method, it is preferable that the at least two electromagnetic steel sheets are overlapped so as to cancel the thickness deviation of these electromagnetic steel sheets. A wound body of electrical steel sheets is usually manufactured by cutting an original fabric manufactured by rolling into a predetermined width. The original fabric obtained by rolling has a feature that the thickness varies depending on the position in the width direction, more specifically, the central portion is thick and the outside is thin. The wound body obtained from such an original fabric varies in thickness. Understand the thickness characteristics of the electrical steel sheets that make up each roll, select a plurality of electrical steel sheets to be superposed based on the characteristics, and then superimpose them so as to offset the thickness deviation of these electrical steel sheets Thus, it is possible to obtain a processed plate suitable for manufacturing. For example, by setting the thickness of the plate to be processed within a predetermined range, it is possible to sufficiently suppress the occurrence of poor feeding due to interference with the guide when the plate to be processed moves in the mold. In addition, when using two electromagnetic steel sheets whose upper and lower surfaces are not sufficiently parallel in the width direction, the thin side of one electromagnetic steel sheet and the thick side of the other electromagnetic steel sheet may overlap ( (See FIG. 9). By using a plurality of electromagnetic steel sheets obtained by punching such a processed plate, a laminated iron core closer to the designed shape can be manufactured.

  The plurality of electromagnetic steel plates constituting the workpiece plate may be fixed to each other by an oil film formed between these electromagnetic steel plates, or may be fixed to each other by welding, caulking, or an adhesive. By providing an oil film between adjacent electromagnetic steel sheets, there is an advantage that the whole of the electromagnetic steel sheets having a narrow width can be bonded to the electromagnetic steel sheets having a wide width. On the other hand, welding, caulking, or an adhesive has an advantage that adjacent electromagnetic steel sheets can be firmly fixed. In order to enjoy both of these advantages, fixing by an oil film and fixing by welding, caulking, or an adhesive may be used in combination.

  From the viewpoint of more stably performing the work of feeding the work plate in the mold, it is preferable that the width of the lowermost electromagnetic steel sheet among the plurality of electromagnetic steel sheets constituting the work plate is the largest.

  From the viewpoint of realizing high production efficiency, a progressive die may be adopted as the die. In this case, in the punching method, (c) a step of punching a workpiece plate in a progressive die and (d) a step of advancing the workpiece plate in the progressive die, a plurality of electromagnetic steel plates are obtained. You may manufacture the processed body which overlapped and was processed into the predetermined shape continuously.

  In the step (c), when forming the pilot hole for alignment, the pilot hole is formed so as to penetrate only the widest electromagnetic steel sheet among the plurality of electromagnetic steel sheets constituting the workpiece plate. Is preferred. By adopting such a configuration, it is possible to sufficiently suppress the phenomenon that the pilot pin for forming the pilot hole is caught on the work plate after the pilot hole is punched. From the same viewpoint, in the step (c), among the plurality of electromagnetic steel sheets constituting the workpiece plate, an area including the edge of the next wide electromagnetic steel sheet while penetrating the widest electromagnetic steel sheet. A pilot hole may be formed so as to penetrate (see FIG. 11).

  Conventionally, when the thickness of the electromagnetic steel sheet is relatively thin (for example, 0.1 to 0.3 mm), the defect that the work of feeding the work plate is not accurately performed has been remarkable, whereas the punching according to the present invention is performed. According to the method, even when an electromagnetic steel sheet having a thickness of 0.1 to 0.3 mm is used, the occurrence of the above problems can be sufficiently suppressed.

  According to the present invention, it is possible to simultaneously punch out a plurality of electromagnetic steel sheets with sufficiently high accuracy and to sufficiently reduce material costs.

It is a perspective view which shows an example of the stator (stator) which consists of a laminated iron core. It is sectional drawing which follows the II-II line | wire in FIG. It is a perspective view which shows an example of the rotor (rotor) which consists of a laminated iron core. It is a schematic diagram which shows an example of the apparatus for manufacturing a laminated iron core. It is sectional drawing which shows an example of a processed board typically. (A)-(e) is a top view which shows an example of the to-be-processed board in which various punching processes were given, (f) is a top view which shows the processed body processed into the predetermined shape. It is a schematic diagram which shows an example of the punching apparatus provided with the roll which apply | coats oil to the back surface of an electromagnetic steel plate. It is sectional drawing which shows the other example of a to-be-processed board typically. It is sectional drawing which shows the further another example of a processed board typically. (A) And (b) is sectional drawing which shows typically the further another example of a to-be-processed board. (A)-(c) is a top view which shows the variation of the positional relationship with a pilot hole and the edge of an electromagnetic steel plate with a narrow width | variety. (A)-(c) is a top view which shows the further variation of the position of a pilot hole. It is a top view which shows a division type laminated iron core for stators.

  Embodiments of the present invention will be described in detail with reference to the drawings. In the following description, the same reference numerals are used for the same elements or elements having the same functions, and redundant description is omitted.

<Laminated iron core constituting the stator>
FIG. 1 is a perspective view of a laminated iron core S constituting a stator. The shape of the laminated iron core S is substantially cylindrical, and the opening Sa located at the center is for arranging the laminated iron core (rotor) R shown in FIG. The laminated iron core S has a substantially annular yoke portion Sy and a teeth portion St extending in the center direction from the inner peripheral side of the yoke portion Sy. Depending on the application and performance of the motor, the width of the yoke portion Sy (W in FIG. 1) is about 2 to 40 mm. The laminated iron core S shown in FIG. 1 has six teeth portions St. The number of teeth portions St is not limited to six.

  As shown in FIGS. 1 and 2, the laminated iron core S includes a laminated body 10 composed of a plurality of electromagnetic steel plates MS processed into a predetermined shape. The plurality of electromagnetic steel plates MS each have a crimp 2S. The laminated body 10 is comprised by joining the electromagnetic steel plates MS adjacent in the up-down direction by caulking 2S. In addition, as shown in FIG. 2, the electromagnetic steel sheet MS located on the lowermost surface has perforations 3 instead of the caulking 2S so that the laminated bodies 10 are not joined to each other when the plurality of laminated bodies 10 are stacked.

<Laminated iron core constituting the rotor>
FIG. 3 is a perspective view of the laminated iron core R constituting the rotor. The shape of the laminated iron core R is substantially cylindrical, and the opening Ra located at the center is for mounting a shaft (not shown). A convex key Rc is provided on the inner peripheral surface Rb constituting the opening Ra.

  The laminated iron core R includes a laminated body 20 made of a plurality of electromagnetic steel plates MR and a plurality of magnet fixing openings 25. The plurality of electromagnetic steel plates MR each have a crimp 2R. The laminated body 20 is comprised by joining the electromagnetic steel plates MR adjacent in the up-down direction by caulking 2R. The laminate 20 has a total of 16 openings 25. Two adjacent openings 25 form a pair, and eight pairs of openings 25 are arranged at equal intervals along the outer periphery of the stacked body 20. Each opening 25 extends from the upper surface 20 a to the lower surface 20 b of the stacked body 20. The total number of openings 25 is not limited to 16, but may be determined according to the application of the motor, the required performance, and the like. Further, the shape and position of the opening 25 may be determined according to the use of the motor, the required performance, and the like.

  Magnets (not shown) are accommodated in the opening 25 side by side in the vertical direction. The magnet is a permanent magnet, and for example, a sintered magnet such as a neodymium magnet can be used. In addition, the number of magnets put in each opening 25 may be one or more. The type of magnet may be determined according to the application of the motor and the required performance. For example, a bonded magnet may be used in place of the sintered magnet, and it is divided into a plurality of thickness direction or width direction, or both. A magnet may be used. After putting the magnet of the opening 25, the magnet can be fixed in the opening 25 by filling the opening 25 with a resin (for example, a thermosetting resin composition).

<Punching device>
FIG. 4 is a schematic diagram showing an example of a punching device for manufacturing the electromagnetic steel sheet MS and the electromagnetic steel sheet MR constituting the laminated iron core S and the laminated iron core R by punching. The punching apparatus 100 shown in the figure includes an uncoiler (winding body holder) 111 to which a winding body C1 of a first electromagnetic steel plate M1 is mounted and an uncoiler (winding) to which a winding body C2 of a second electromagnetic steel sheet M2 is mounted. (Heavy body holder) 112, press machine 120, feed device (feed means) 130, progressive die 140 operated by press machine 120, oil provided between uncoilers 111, 112 and progressive die 140. Spray nozzle (oil film forming means) 150.

  The uncoilers 111 and 112 respectively hold the winding bodies C1 and C2 rotatably. The two electromagnetic steel plates M1 and M2 constituting the wound bodies C1 and C2 have different widths (see FIG. 5). The electromagnetic steel plates M1 and M2 drawn from the wound bodies C1 and C2 are overlapped by the feeding device 130. The feeding device 130 has a pair of rollers 130a and 130b that sandwich the electromagnetic steel plates M1 and M2 from both sides. The electromagnetic steel plates M1 and M2 are introduced into the progressive die 140 via the feeder 130.

  Prior to being introduced into the feeding device 130, oil spraying by the nozzle 150 is performed on the electromagnetic steel sheets M1 and M2. That is, as shown in FIG. 4, oil is sprayed from the nozzle 150 toward the back surface of the electromagnetic steel plate M1 and the surface of the electromagnetic steel plate M2. After spraying oil between the back surface of the electromagnetic steel plate M1 and the surface of the electromagnetic steel plate M2, the electromagnetic steel plates M1 and M2 are introduced into the feeding device 130, whereby two electromagnetic steel plates M1 and M2 are introduced as shown in FIG. And the to-be-processed board W which has the oil film F interposed between these electromagnetic steel plates M1 and M2 is comprised.

  In addition, although the structure which sprays oil toward both the back surface of the electromagnetic steel plate M1 and the surface of the electromagnetic steel plate M2 with the nozzle 150 was illustrated here, the nozzle which sprays oil on the back surface of the electromagnetic steel plate M1, and the electromagnetic steel plate M2 You may provide the nozzle which sprays oil on the surface. Alternatively, the nozzle 150 may spray oil only on one of the back surface of the electromagnetic steel plate M1 and the surface of the electromagnetic steel plate M2.

    The thickness of the electromagnetic steel sheets M1 and M2 may be about 0.1 to 0.5 mm. Conventionally, when the thickness of the magnetic steel sheet is relatively thin (for example, 0.1 to 0.3 mm), unless the portion that does not become a product remains excessively, the work of feeding the work plate is caused due to insufficient strength of the work plate. In some cases, it could not be implemented properly. On the other hand, according to the punching method according to the present embodiment, if an excessively non-product portion is provided only in the electromagnetic steel plate M2 positioned below in the feed mold 140, the work of feeding the workpiece W is sufficiently performed. It can be implemented stably. As the electromagnetic steel plates M1 and M2, electromagnetic steel plates having a thickness of 0.1 to 0.3 mm may be used, respectively, and further, electromagnetic steel plates having a thickness of 0.1 to 0.18 mm may be used. In addition, the total thickness of the work plate W is preferably 0.2 to 1.0 mm, and more preferably 0.3 to 0.5 mm. If the thickness of the work plate W is less than 0.2 mm, the effect obtained by superimposing a plurality of magnetic steel sheets tends to be reduced, and if it exceeds 1.0 mm, the flexibility of the work plate W is increased. There is a tendency to become smaller. The thickness of the oil film F itself may be about 0.001 mm.

  Conventionally, when the width of the electromagnetic steel sheet is wide (for example, 250 to 500 mm), the feeding in the progressive die 140 is likely to be hindered due to insufficient strength of the electromagnetic steel sheet. On the other hand, according to the punching method according to the present embodiment, even if electromagnetic steel sheets having a width of 250 to 500 mm are used as the electromagnetic steel sheets M1 and M2, they are superposed and the product is applied to one of the electromagnetic steel sheets (electromagnetic steel sheet M2). By providing an excessive portion that does not become necessary, feeding in the progressive die 140 can be performed stably. That is, as the electromagnetic steel plates M1 and M2, electromagnetic steel plates having a width of 250 to 500 mm may be used, and further, electromagnetic steel plates having a width of 400 to 500 mm may be used.

  The width of the electromagnetic steel sheet M2 is preferably the maximum width of the product to be punched from the work plate W plus 4 to 20 mm, more preferably the maximum width plus 6 to 15 mm, and still more preferably the maximum width plus 8 to 8 mm. 10 mm. The “maximum product width” means the maximum width in a direction perpendicular to the longitudinal direction of the processed plate W. If the width of the magnetic steel sheet M2 is less than the maximum width of the product plus 4 mm, the strength of the processed plate W is insufficient and the feeding work is likely to be hindered. If the width of the product exceeds the maximum width of 20 mm, the effect of reducing the material cost is ineffective. It tends to be enough.

  The width of the electromagnetic steel plate M1 only needs to be narrower than the width of the electromagnetic steel plate M2, and the difference between the width of the electromagnetic steel plate M2 and the width of the electromagnetic steel plate M1 may be 0.1 mm or more. From the viewpoint of further reducing the material cost, the difference between the width of the electromagnetic steel sheet M2 and the width of the electromagnetic steel sheet M1 is preferably 2 mm or more, more preferably 4 mm or more.

  The width of the electromagnetic steel sheet M1 is preferably the maximum width of the product to be punched from the work plate W plus 4 to 18 mm, more preferably the maximum width plus 4 to 13 mm, and even more preferably the maximum width plus 6 to 6 mm. 8 mm. If the width of the magnetic steel sheet M1 is less than the maximum width of the product plus 2 mm, the vicinity of the end surface in the width direction of the processed plate W will be punched out with a mold, and the product dimensions are likely to deteriorate, exceeding the maximum width of the product plus 18 mm. And the effect of reducing material costs tends to be insufficient. In addition, when notches may be formed on the outer periphery of the product, punching may be performed so as to exceed the width of the electromagnetic steel sheet M1.

  The punching apparatus 100 performs a punching process on the workpiece plate W on which the electromagnetic steel plates M1 and M2 are overlapped via the oil film F. The oil film F plays a role of bonding the two electromagnetic steel plates M1 and M2 on the work plate W. For this reason, according to the punching device 100, the two electromagnetic steel plates M1 and M2 can be punched simultaneously with sufficiently high accuracy, and the occurrence of residue rise can be sufficiently suppressed. “Left-up” means a phenomenon in which a material punched into a punch included in a mold (referred to as “scrap” or “slip-out”) adheres.

As the oil for forming the oil film F, for example, punching work oil (also referred to as stamping oil), mineral oil, silicone oil, or the like can be used. According to the study of the present inventors, the oil constituting the oil film F is preferably a kinematic viscosity at 40 ° C. and at 0.9 mm ² / s or more, more preferably 0.9~10mm ² / s. Force kinematic viscosity at 40 ° C. of oil bonding the electromagnetic steel plates M1 and the electromagnetic steel sheet M2 is less than 0.9 mm ² / s is liable to be insufficient, while oil spray by the nozzle exceeds 10 mm ² / s It tends to be difficult. In addition, kinematic viscosity here means the value measured by the kinematic viscosity test method as described in JISK2283 (2000).

  Of the oils listed above, it is preferable to use a punching working oil that is also used in the progressive die 140. In this case, it is possible to supply the punching work oil to the nozzle 150 through the branch pipe by branching the pipe for supplying the punching work oil to the progressive die 140 in the middle.

<Manufacturing method of laminated core>
A method for manufacturing the laminated iron core S will be described with reference to FIGS. The laminated iron core S integrates a process (the following (A) to (E) steps) for obtaining the electromagnetic steel sheet MS by punching the workpiece W and a plurality of stacked electromagnetic steel sheets MS (laminated body 10). To be manufactured through a process (step (F) below). More specifically, the method for manufacturing the laminated iron core S includes the following steps.
(A) A step of preparing two wound bodies C1 and C2 made of electromagnetic steel plates M1 and M2 having different widths.
(B) Two electromagnetic steel plates M1 and M2 drawn out from the windings C1 and C2 and fixed in an overlapped manner, and an oil film F interposed between the two electromagnetic steel plates M1 and M2. A step of supplying the workpiece W to the progressive die 140.
(C) A step of punching the workpiece W in the progressive die 140.
(D) A step of moving the work plate W forward in the progressive die 140.
(E) A step of continuously obtaining a workpiece WS processed into a predetermined shape by repeating the step (C) and the step (D).
(F) The process of obtaining the laminated iron core S by fastening the laminated body 10 obtained by superimposing the some processed body WS with the crimp 2S.

  First, windings C1 and C2 of electromagnetic steel sheets are prepared (step (A)), and these are mounted on the uncoilers 111 and 112, respectively. The lengths of the electromagnetic steel plates M1 and M2 constituting the wound bodies C1 and C2 are, for example, 500 to 10,000 m. When the remaining winding body in use decreases, a new winding body is prepared, and the starting end of the new winding body and the terminal end of the winding body in use are joined by welding, for example.

A plate to be processed W is obtained by spraying oil from the nozzle 150 between the electromagnetic steel plates M1 and M2 drawn out from the wound bodies C1 and C2, respectively. The workpiece plate W is supplied to the progressive die 140 via the feeder 130 (step (B)). The ratio of the oil film area A _F to the area A _M of the electromagnetic steel sheet M1 is not limited as long as the two electromagnetic steel sheets M1 and M2 can be bonded together with the oil film F with a sufficiently high strength, but this ratio (A _F / A _M ) is preferably 0.8 or more, more preferably 0.9 or more.

By spraying oil from the nozzle 150, the oil film F having a sufficiently uniform thickness can be formed. If the thickness of the oil film F is not uniform, the force for bonding the two electromagnetic steel sheets M1, M2 tends to be insufficient. Further, even if the amount of oil constituting the oil film F is too large or too small, the force for bonding the two electromagnetic steel plates M1 and M2 tends to be insufficient. Although depending on the viscosity of the oil film F, the ambient temperature, etc., the mass of the oil film F per unit area of the magnetic steel sheet M1 is preferably 0.5 to 2.0 g / m ² , more preferably 0.5 to 1. 0 g / m ² . If the amount of oil constituting the oil film F is excessive, excess oil may adhere to the rollers 130a and 130b of the feeding device 130 and cause a feeding error.

  As shown in FIG. 5, the electromagnetic steel plate M1 is overlapped with the central portion in the width direction of the electromagnetic steel plate M2. In other words, the electromagnetic steel plate M1 is not overlapped on both peripheral edges in the width direction of the processed plate W, and the region Wa made of only the electromagnetic steel plate M2 is provided with the same width.

  The punching operation (step (C)) by the punch (not shown) provided in the progressive die 140 and the feeding operation ((D) step) of the work plate W by the feeding device 130 are repeated. Thereby, the processed object WS processed into the predetermined shape is obtained ((E) process).

  The step (E) will be described with reference to FIG. FIG. 6A shows a state in which pilot holes P for alignment are formed in the work plate W. FIG. In this embodiment, the pilot hole P is formed in the area | region Wa which consists only of an electromagnetic steel plate M2. By forming the pilot hole P in the region Wa, a phenomenon that the pilot pin for forming the pilot hole P is caught on the work plate W can be sufficiently suppressed. When the pilot hole P is formed in the region where a plurality of electromagnetic steel sheets are laminated, the pilot pin is easily caught on the work plate. To suppress this, the pilot pin stroke speed is reduced, or the pilot hole diameter is reduced. It may be necessary to take measures such as In this case, if the stroke speed is lowered, the productivity is lowered. On the other hand, if the diameter of the pilot hole is made small, the problem of scrap rise tends to occur.

  FIG. 6B shows a state in which a total of six openings H1 constituting the inner peripheral surface of the yoke portion Sy and the side surface of the tooth portion St of the laminated core S are formed.

  FIG. 6C shows a state in which the crimp 2S is further formed. The crimp 2S is used for fastening a plurality of workpieces WS.

  FIG. 6D shows a state in which the inner peripheral surface of the workpiece WS is formed by forming the opening H2 in the workpiece plate W.

  FIG. 6E shows a state where an opening H3 constituting the outer peripheral surface of the yoke portion Sy of the laminated core S is further formed. By forming the opening H3, a processed body WS having a shape shown in FIG. 6F is obtained. Two electromagnetic steel plates MS are overlaid on the workpiece WS.

  A laminated core R shown in FIG. 1 is obtained by superposing a predetermined number of workpieces WS obtained through the above steps and joining them together by caulking 2S (step (F)).

  According to the method for manufacturing a laminated core according to the present embodiment, the two electromagnetic steel plates M1 and M2 can be simultaneously punched with sufficiently high accuracy, and the material cost can be sufficiently reduced. In addition, the workpiece for rotors can be manufactured through the process similar to the manufacturing method of the above-mentioned laminated iron core S by using the progressive die 140 according to the shape.

  As mentioned above, although one Embodiment of this invention was described in detail, this invention is not limited to the said embodiment. For example, in the said embodiment, although the case where oil was sprayed using the nozzle 150 was illustrated, as shown in FIG. 7, using the roll 151 instead of the nozzle 150, oil is applied to the back surface of the electromagnetic steel plate M1. It may be applied. In this aspect, the oil film forming means is configured by the container 152 capable of containing oil and the roll 151 provided to be rotatable with respect to the container 152. When oil is put into the container 152, the lower part of the roll 151 is immersed in the oil. Two rolls may be provided to apply oil to both the back surface of the electromagnetic steel sheet M1 and the surface of the electromagnetic steel sheet M2.

  FIG. 5 according to the above embodiment schematically illustrates the processed plate W on which the electromagnetic steel plates M1 and M2 having the same thickness are overlapped, but the thicknesses of the electromagnetic steel plates M1 and M2 are different from each other. You may do it. In this case, from the viewpoint of more stably performing the work of feeding the work plate W, the thickness of the electromagnetic steel sheet M2 positioned below in the progressive die 140 is larger than the thickness of the electromagnetic steel sheet M1 positioned above. Is preferred (see FIG. 8). By grasping in advance the characteristics of the thickness of the electrical steel sheets constituting the wound body, selecting the two electrical steel sheets M1 and M2 to be superposed based on the characteristics, and superimposing them, the covering of a predetermined thickness is obtained. A processed plate W can be obtained. For example, by setting the thickness of the work plate W within a predetermined range, it is possible to sufficiently suppress the occurrence of feed failure due to interference with the guide when the work plate W moves in the progressive die 140. In addition, as long as the intensity | strength of the to-be-processed board W can fully be ensured, you may make the thickness of the electromagnetic steel plate M2 located below in the progressive die 140 smaller than the thickness of the electromagnetic steel plate M1 located above.

  Although FIG. 5 which concerns on the said embodiment typically illustrated the to-be-processed board W with which two electromagnetic steel plates M1 and M2 with sufficiently uniform thickness were overlapped, it has plate | board thickness deviation in the width direction. The electromagnetic steel plates M1, M2 (in other words, the electromagnetic steel plates M1, M2 whose thickness in the width direction is not uniform) may be used. In this case, as shown in FIG. 9, the electromagnetic steel plate M1 and the electromagnetic steel plate M2 may be overlapped so as to cancel the thickness deviation between the two electromagnetic steel plates M1 and M2. That is, what is necessary is just to make it the thin side of the electromagnetic steel plate M1 and the thick side of the electromagnetic steel plate M2 overlap. To grasp in advance the characteristics (thickness, thickness deviation, etc.) of the electrical steel sheets that make up the prepared multiple rolls, select the rolls to be used, and optimize the orientation of the multiple electrical steel sheets Thus, the laminated cores S and R closer to the designed shape can be manufactured.

  Although FIG. 5 which concerns on the said embodiment typically illustrated the to-be-processed board W with which the electromagnetic steel plate M1 was piled up in the center part of the width direction of the electromagnetic steel plate M2 located below, the electromagnetic steel plate M1 is an electromagnetic steel plate. As long as it does not protrude from M2, the electromagnetic steel plate M1 may be overlapped at a position shifted in the width direction from the central portion of the electromagnetic steel plate M2 (see FIGS. 10A and 10B). The guide G shown in FIG. 10B is for preventing the displacement of the work plate W in the progressive die 140. The guide G has a facing surface Ga corresponding to the shape of the side portion of the work plate W. In this example, the opposing surface Ga is formed in a step shape.

  In the said embodiment, although the case where the pilot hole P was formed in the area | region Wa which consists only of the electromagnetic steel plate M2 in the to-be-processed board W in the (C) process was illustrated, it penetrated the area | region including the edge M1a of the electromagnetic steel plate M1. Alternatively, the pilot hole P may be formed (see the pilot hole P above (a) to (c) in FIG. 11). As shown in FIG. 11, when the pilot hole P is circular, it is preferable that the center of the pilot hole P is located in a region Wa composed only of the electromagnetic steel sheet M2 from the viewpoint of easy removal of the pilot pin (see FIG. 11). (See (a) and (b)).

  FIGS. 12A to 12C are plan views showing further variations of the position of the pilot hole P. FIG. The pilot hole P shown in FIG. 12A is provided at a position where the two electromagnetic steel plates M1 and M2 overlap. Such a configuration is useful when the difference in width between the electromagnetic steel sheets M1 and M2 is small. The pilot hole P shown in FIG. 12B is formed so as to contact the edge M1a of the electromagnetic steel sheet M1. The upper pilot hole P and the lower pilot hole P shown in (c) of FIG. 12 are provided not at the same position in the feed direction of the work plate W but at positions shifted forward and backward in the feed direction of the work plate W. It has been. Such a configuration is useful when a laminated iron core having a portion protruding in the outer peripheral direction (for example, an ear portion for bolting) is manufactured or when multiple rows are taken.

  In the said embodiment, the case where the punching process was implemented with respect to the to-be-processed board W which prepared two wound bodies C1 and C2 and overlapped two electromagnetic steel plates M1 and M2 via the oil film F was illustrated. However, a punching process may be performed on a workpiece plate in which three or more electromagnetic steel plates are overlapped via the oil film F. In this case, from the viewpoint of more stably performing the work of feeding the work plate W in the progressive die 140, the width of the lowermost magnetic steel sheet among the plurality of electromagnetic steel sheets constituting the work plate W. Is preferably the largest. From the viewpoint of punching accuracy, the upper limit of the number of electromagnetic steel sheets constituting the work plate may be about five.

  In the above-described embodiment, the case where the two electromagnetic steel plates M1 and M2 are fixed to each other by the oil film F is illustrated. However, instead of the oil film F, the electromagnetic steel plates M1 and M2 may be fixed to each other by welding, caulking, or adhesive. Good. Since the two magnetic steel sheets M1 and M2 have different widths (see FIG. 5), there is an advantage that welding is easy. In addition, what is necessary is just to perform welding to the location which is not used as a product.

  In the said embodiment, although the case where the crimping 2S and 2R were formed with respect to the to-be-processed board W was illustrated, instead of crimping, the electrical steel plates MS or the electrical steel plates MR are fastened together by welding, resin or adhesive. Also good.

  In the above embodiment, the case where only the workpiece WS is manufactured from the workpiece plate W has been exemplified, but both the workpiece WR and the workpiece WS may be manufactured from the workpiece plate W.

In the above embodiment, the monolithic laminated cores S and R and the manufacturing method thereof are exemplified. However, the present invention is not limited to the monolithic laminated cores S and R, and is applied to the split type laminated cores and the manufacturing method thereof. May be. The laminated iron core _SD shown in FIG. 13 is configured by a total of twelve laminated bodies 30 arranged in a circumferential direction. Each laminated body 30 is provided with a dummy caulking portion 30a. The dummy caulking portion 30a is removed after the laminated body 30 is fastened by welding, adhesion, or a resin material. In addition, the number of the laminated bodies 30 and the dummy caulking portions 30a is not limited to twelve.

2R, 2S ... caulking, 140 ... progressive die (die), C1, C2 ... winding, F ... oil film, M1, M2 ... electromagnetic steel plate, M1a ... edge of electromagnetic steel plate, R ... laminated iron core for rotor , S: laminated iron core for stator, S _D : split laminated iron core, W: work plate, WR, WS: processed body.

Claims (8)

(A) preparing a roll of at least two electrical steel sheets;
(B) supplying a work plate made of at least two electromagnetic steel plates pulled out from each of the winding bodies and fixed to each other in a superposed state to a mold;
(C) a step of punching the work plate in the mold;
With
The punching method in which the widths of the two electromagnetic steel sheets constituting the two wound bodies are different from each other.   The punching method according to claim 1, wherein the plurality of electromagnetic steel plates constituting the workpiece plate are fixed to each other by an oil film formed between the electromagnetic steel plates.   The punching method according to claim 1 or 2, wherein the plurality of electromagnetic steel plates constituting the workpiece plate are fixed to each other by welding, caulking, or an adhesive.   The punching method according to any one of claims 1 to 3, wherein a width of an electromagnetic steel sheet located at a lowermost position among a plurality of electromagnetic steel sheets constituting the workpiece plate is the largest in the mold.   The mold is a progressive mold, and (c) a step of punching the processed plate in the mold and (d) a step of moving the processed plate forward in the mold, The punching method as described in any one of Claims 1-4 which manufactures the processed body by which the some electromagnetic steel plate overlapped and was processed into the predetermined shape continuously.   5. The punching method according to claim 4, wherein, in the step (c), a pilot hole is formed so as to penetrate only the widest electromagnetic steel plate among the plurality of electromagnetic steel plates constituting the workpiece plate.   In the step (c), among the plurality of electromagnetic steel sheets constituting the workpiece plate, the electromagnetic steel sheet having the widest width is penetrated and the region including the edge of the next wide electromagnetic steel sheet is penetrated. The punching method of Claim 4 which forms a pilot hole.   The punching method according to any one of claims 1 to 7, wherein the thickness of the electromagnetic steel sheet is 0.1 to 0.3 mm.

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