Manufacturing apparatus and manufacturing method for laminated iron core

Abstract

Provided are a manufacturing apparatus and a manufacturing method for a laminated iron core, the apparatus and method being capable of suppressing unnecessary spreading of an adhesive and reducing the risk of the adhesive entering unintended areas. According to the present invention, a manufacturing apparatus 1 for a laminated iron core 4 forms an iron core thin plate 3 having a predetermined shape by punching from a steel plate 2, and manufactures a laminated iron core 4 in which a predetermined number of the iron core thin plates 3 are laminated and bonded. The manufacturing apparatus 1 comprises: an adhesive application means 14 for applying an adhesive 140 to a portion 2a of a steel plate 2 corresponding to an iron core thin plate 3; and a punching part 15 for punching the iron core thin plate 3 from the steel plate 2 after the application of the adhesive 140 by the adhesive application means 14, the punching part 15 being composed of a die including an upper die 130 and a lower die 131. The upper die 130 or the lower die 131 is provided with: a recessed part 50 provided at a position corresponding to the part 2a to which the adhesive 140 has been applied; and a ventilation port 51 for providing communication between the internal space of the recessed part 50 and the outside of the upper die 130 or the lower die 131.

Description

Manufacturing device and manufacturing method for laminated iron core

[0001] The present invention relates to a laminated core manufacturing apparatus and method for manufacturing a laminated core by punching out thin core plates of a predetermined shape from a steel plate and stacking and bonding a predetermined number of thin core plates.

[0002] The cores used in rotating electrical machines are laminated cores, which are made up of a predetermined number of laminated thin core plates. The thin core plates are joined together by various methods. When crimping and welding are used as joining methods, mechanical or thermal stresses during joining and interlayer short circuits can deteriorate the magnetic properties of the laminated core, preventing the laminated core from fully performing its functions. For this reason, efforts have been made to laminate and bond the thin core plates, as shown in Patent Document 1 below.

[0003] Patent Document 1 describes a laminated core manufacturing device that includes a progressive die means having upper and lower dies that sequentially punches out iron core sheets from an intermittently transported thin steel strip, and an adhesive applicator provided within the lower die that applies adhesive to portions of the thin steel strip that correspond to the iron core sheets. The adhesive applicator includes an adhesive discharge unit including a nozzle block with multiple discharge holes on its upper surface, and an adhesive supply unit that supplies adhesive to the adhesive discharge unit at a predetermined pressure to discharge adhesive from the multiple discharge holes. The adhesive applicator also includes an advancing / retracting drive unit that moves the adhesive discharge unit toward and away from the adhesive application surface of the thin steel strip. The advancing / retracting drive unit moves the adhesive discharge unit toward and away from the adhesive application surface of the thin steel strip, thereby switching between performing and not performing the adhesive application process by the adhesive discharge unit. A laminated core consisting of a predetermined number of iron core sheets is separated from the group of iron core sheets at the position of the iron core sheets that do not have adhesive applied.

[0004] Japanese Patent Application Laid-Open No. 2017-216873

[0005] When punching the iron core thin plate after applying adhesive as in the conventional device described in the above-mentioned Patent Document 1, wind pressure acts on the adhesive due to the relative movement between the steel plate and the die, which can cause the adhesive to spread unnecessarily. Unnecessary spreading of the adhesive can lead to the adhesive getting into unintended areas. This can cause increased friction during punching, deviations in dimensional accuracy, and / or accelerated wear of the blades. In particular, there is a demand for increased punching speeds for iron core thin plates in response to increasing demand for rotating electrical machines, and as the punching speed increases, this unwanted spreading of the adhesive becomes more pronounced.

[0006] The present invention has been made to solve the above-mentioned problems, and one of its purposes is to provide a manufacturing apparatus and manufacturing method for a laminated iron core that can suppress unnecessary spreading of adhesive and reduce the risk of the adhesive getting into unintended areas.

[0007] In one embodiment, the laminated core manufacturing apparatus of the present invention is an apparatus for manufacturing a laminated core that punches out thin iron core plates of a predetermined shape from a steel plate and manufactures a laminated iron core in which a predetermined number of thin iron core plates are stacked and bonded together, and is equipped with an adhesive application means for applying adhesive to portions of the steel plate corresponding to the thin iron core plates, and a punching section composed of dies including an upper die and a lower die, for punching out the thin iron core plates from the steel plate after the adhesive has been applied by the adhesive application means, and the upper die or lower die is provided with a recess provided at a position corresponding to the portion where the adhesive has been applied, and an air vent that connects the internal space of the recess to the outside of the upper die or lower die.

[0008] In one embodiment, a method for manufacturing a laminated core according to the present invention includes manufacturing a laminated core using the above-described laminated core manufacturing apparatus.

[0009] According to one embodiment of the laminated core manufacturing apparatus and manufacturing method of the present invention, the upper or lower die is provided with a recess at a position corresponding to the area where the adhesive is applied, and a vent that connects the internal space of the recess to the outside of the upper or lower die, thereby preventing the adhesive from spreading unnecessarily and reducing the risk of the adhesive getting into unintended areas. This configuration is particularly useful when increasing the punching speed.

[0010] FIG. 1 is an explanatory diagram showing a laminated iron core manufacturing apparatus according to embodiment 1 of the present invention. FIG. 2 is an explanatory diagram showing the adhesive application means and upper mold of FIG. 1. FIG. 3 is an explanatory diagram showing the spread of adhesive when no vent holes are provided in FIG. 2. FIG. 4 is an explanatory diagram showing the upper mold and lower mold of FIG. 1 in more detail. FIG. 5 is an explanatory diagram showing the upper mold lowered to a position where the steel plate is clamped by the plate clamp and die of FIG. 4. FIG. 6 is an explanatory diagram showing the upper mold lowered further from the state of FIG. 5. FIG. 7 is an explanatory diagram showing the adhesive application means and upper mold in a laminated iron core manufacturing apparatus according to embodiment 2 of the present invention.

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to each embodiment, and the components can be modified and embodied without departing from the spirit of the present invention. Furthermore, various inventions can be formed by appropriately combining multiple components disclosed in each embodiment. For example, some components may be omitted from all the components shown in the embodiments. Furthermore, components of different embodiments may be appropriately combined.

[0012] Embodiment 1. Figure 1 is an explanatory diagram showing a manufacturing apparatus 1 for manufacturing a laminated core 4 according to embodiment 1 of the present invention, Figure 2 is an explanatory diagram showing the adhesive application means 14 and upper mold 130 of Figure 1, and Figure 3 is an explanatory diagram showing the spread of adhesive 140 when vent holes 51 of Figure 2 are not provided. The manufacturing apparatus 1 shown in Figure 1 is an apparatus for punching out and forming thin core sheets 3 of a predetermined shape from a steel plate 2, and for manufacturing a laminated core 4 in which a predetermined number of thin core sheets 3 are stacked and bonded together.

[0013] As shown in Figure 1, the manufacturing apparatus 1 of this embodiment may have a reel 10, a feeding device 11, an oiling device 12, and press equipment 13. A coil of steel sheet 2 is attached to the reel 10. The steel sheet 2 unwound from the reel 10 is fed to the press equipment 13 through the feeding device 11. The oiling device 12 is disposed between the feeding device 11 and the press equipment 13, and supplies press oil to the surface of the steel sheet 2 before the steel sheet 2 is introduced into the press equipment 13. The press equipment 13 has an upper die 130 and a lower die 131, and the upper die 130 and the lower die 131 punch out the iron core thin plate 3 from the steel sheet 2.

[0014] The manufacturing apparatus 1 of this embodiment includes an adhesive application means 14 , a punching section 15 , a stacking section 16 and a conveying device 17 .

[0015] The adhesive application means 14 is for applying adhesive 140 (see FIG. 2 ) to the portion 2 a of the steel sheet 2 corresponding to the iron core thin plate 3. The adhesive application means 14 may be built into the press equipment 13 (upper die 130 or lower die 131), or may be arranged upstream of the press equipment 13 in the feed direction D1 of the steel sheet 2 as shown in FIGS. 1 and 2 . In the illustrated embodiment, the adhesive application means 14 is arranged upstream of the oil application device 12 and downstream of the feed device 11.

[0016] The adhesive applicator 14 may apply adhesive 140 to the surface of the steel plate 2. As shown in FIG. 2 , the adhesive applicator 14 may apply adhesive 140 to the upper surface of the steel plate 2. The adhesive applicator 14 may spray adhesive 140 onto the upper surface of the steel plate 2 from a nozzle 141 arranged above the steel plate 2. On the left side of the lower part of FIG. 2 , a portion 2 a corresponding to the core thin plate 3 is shown by a thin line. The core thin plate 3 may have an annular yoke and a plurality of teeth that protrude radially inward from the yoke and are spaced apart from one another around the yoke. The adhesive 140 may be applied at any position, but in the illustrated embodiment, the adhesive 140 is applied to a plurality of positions on the yoke that are spaced apart from one another around the yoke. The adhesive 140 may be applied to a number of positions that is fewer than the number of teeth.

[0017] The punching unit 15 is composed of dies including an upper die 130 and a lower die 131, and is a unit for punching the core thin sheets 3 from the steel sheet 2 after the adhesive 140 has been applied by the adhesive application means 14. The punching of the steel sheet 2 by the punching unit 15 may be performed in multiple steps. That is, the steel sheet 2 may be punched sequentially in the feed direction D1 of the steel sheet 2 toward the final core thin sheet 3. The punching unit 15 may have a pre-processing unit 150 that punches out the portion of the steel sheet 2 other than the outer shape of the core thin sheet 3 in one or multiple steps, and an outline punching unit 151 that punches out the outer shape of the core thin sheet 3 from the steel sheet 2 after punching by the pre-processing unit 150. The outline punching by the outline punching unit 151 is performed last, and the core thin sheet 3 is punched out of the steel sheet 2 when the outer shape of the core thin sheet 3 has been punched out.

[0018] The lamination section 16 is a section for stacking and adhering the iron core thin plates 3 coated with adhesive 140 to form the iron core thin plate group 30. The lamination section 16 may be built into the lower mold 131 at a position where the punching section 15 performs outline punching. The iron core thin plate group 30 is formed by stacking and adhering a plurality of iron core thin plates 3. An iron core thin plate 3 is dropped onto the iron core thin plate group 30 formed by previously punched iron core thin plates 3, and is adhered in close contact with the upper surface of the iron core thin plate group 30 by the weight of the iron core thin plate 3 itself or the weight of the subsequent iron core thin plate 3.

[0019] The conveying device 17 is a device for conveying the laminated core 4 separated from the core thin plate group 30. The laminated core 4 may be removed from the lower die 131 by the conveying device 17.

[0020] The laminated core 4 may be separated from the group of core laminations 30 by any method. For example, the adhesive application means 14 may not apply adhesive 140 to one of the plurality of core laminations 3, thereby making the group of core laminations 3 separable at the core laminations 3 to which adhesive 140 is not applied. When the core laminations 3 to which adhesive 140 is not applied are referred to as first core laminations and the core laminations 3 to which adhesive 140 is applied are referred to as second core laminations, the laminated core 4 may include one first core lamination and multiple second core laminations stacked and bonded above or below the first core lamination. Alternatively, the adhesive application means 14 may apply adhesive 140 to all of the core laminations 3, and then physically separate the laminated core 4 from the group of core laminations 30.

[0021] Here, as shown in the upper part of Figure 2, the upper mold 130 of this embodiment is provided with a recess 50 located at a position corresponding to the area 2a where the adhesive 140 is applied, and an air vent 51 that connects the internal space of the recess 50 to the outside of the upper mold 130.

[0022] The recess 50 is intended to form a space to prevent the upper die 130 from coming into contact with the adhesive 140, and may be arranged in a position where the steel plate 2 is punched so as to overlap the area 2a to which the adhesive 140 is applied when viewed along the separation direction D2 (vertical direction) of the upper die 130 and the lower die 131. In the illustrated embodiment, the recess 50 is shown as having a back wall 50a to which the vent hole 51 is connected, but the back wall 50a may be omitted and the vent hole 51 may be connected to the entire back end of the recess 50. In other words, the inner diameter of the back end of the recess 50 and the inner diameter of the vent hole 51 may be the same, and the recess 50 and the vent hole 51 may together form a through hole or a passage.

[0023] As described above, the upper die 130 and the lower die 131 punch out the core thin plate 3 from the steel plate 2. If the upper die 130 were not provided with the vent hole 51, as shown in FIG. 3 , the relative movement between the upper die 130 and / or the lower die 131 and the steel plate 2 would cause wind pressure to act on the adhesive 140, which could cause the adhesive 140 to spread unnecessarily. Unnecessary spreading of the adhesive 140 could result in the adhesive 140 getting into unintended areas. This could lead to increased friction during punching, deviations in dimensional accuracy, and / or accelerated wear of the blades. In particular, an increase in the punching speed of the core thin plate 3 is desired in response to increasing demand for rotating electrical machines, and as the punching speed increases, the unwanted spreading of the adhesive 140 becomes more pronounced.

[0024] In contrast, if the upper mold 130 is provided with a vent hole 51 as in the manufacturing apparatus 1 of this embodiment, when the upper mold 130 is lowered toward the lower mold 131, the air inside the recess 50 can be released to the outside of the upper mold 130 through the vent hole 51. This prevents the adhesive 140 from spreading unnecessarily, reducing the risk of the adhesive 140 getting into unintended areas. Therefore, it is possible to avoid increased friction during punching, suppress deviations in dimensional accuracy, and / or avoid the risk of accelerated wear of the blade. This configuration is particularly useful when increasing the punching speed.

[0025] The vent hole 51 extends linearly along the separating direction D2 of the upper mold 130 and the lower mold 131. The vent hole 51 may extend linearly upward from the back wall 50a of the recess 50.

[0026] The recess 50 and the vent 51 may be provided in the pre-processed portion 150. By providing the recess 50 and the vent 51 in the pre-processed portion 150, unnecessary spreading of the adhesive 140 before reaching the outer shape punching portion 151 can be suppressed.

[0027] The outer shape punching section 151 may be provided with a pressing section 52 that presses out the adhesive 140 when punching out the outer shape of the core thin plates 3. The pressing section 52 can increase the area of ​​the adhesive 140 on the core thin plates 3 and reduce the thickness of the adhesive 140. By pressing out the adhesive 140 with the pressing section 52, the core thin plates 3 can be more reliably laminated and bonded in the lamination section 16. Furthermore, the gap between the core thin plates 3 can be reduced.

[0028] The pressing unit 52 may have a pressing unit main body 520 that constitutes a portion that is directly pressed against the adhesive 140. The pressing unit main body 520 is preferably made of a material that can prevent the adhesive 140 from adhering, such as polytetrafluoroethylene (PTFE). The pressing unit main body 520 may be fixed to the upper mold 130, or may be provided so as to be displaceable relative to the upper mold 130. In the illustrated embodiment, the pressing unit 52 includes a position adjustment means 521 that adjusts the height position of the pressing unit main body 520. The position adjustment means 521 may be attached to the upper mold 130. Adjusting the height position of the pressing unit main body 520 allows adjustment of the pressing pressure of the pressing unit main body 520 against the adhesive 140. The position adjustment means 521 may be configured, for example, by a screw or the like that is attached to the upper mold 130 so as to be able to advance and retreat. The pressing unit 52 may also include a buffer mechanism 522 incorporated in the connection between the pressing unit main body 520 and the position adjustment means 521. The buffer mechanism 522 may be made of a spring or a resin with a relatively low modulus of elasticity, and by incorporating the buffer mechanism 522, it is possible to provide the pressing portion 52 with a buffering effect.

[0029] Next, Fig. 4 is an explanatory diagram showing the upper mold 130 and the lower mold 131 of Fig. 1 in more detail, Fig. 5 is an explanatory diagram showing a state in which the upper mold 130 has been lowered to a position where the steel plate 2 is clamped by the plate holder 71 and the die 61 of Fig. 4, and Fig. 6 is an explanatory diagram showing a state in which the upper mold 130 has been further lowered from the state of Fig. 5. Note that Figs. 4 to 6 show the upper mold 130 and the lower mold 131 in the pre-processing section 150 of Fig. 1. The configurations of the upper mold 130 and the lower mold 131 in the outline punching section 151 may be similar to the configurations of the upper mold 130 and the lower mold 131 in the pre-processing section 150, except that a pressing section 52 (see Fig. 2) is provided instead of the recess 50 and the vent hole 51.

[0030] As shown in FIG. 4 , the lower mold 131 may include a lower mold die set 60 , a die 61 , a material lifter 62 , a material stock guide 63 , and a lower mold height post 64 .

[0031] A lower die set 60 is disposed below the lower die 131. A die 61 is fixed onto the lower die set 60. The die 61 is provided with a push-in hole 61a into which a punch 74 of the upper die 130, which will be described later, is pushed together with a part of the steel sheet 2. The lower die set 60 is provided with a removal hole 60a which is connected to the push-in hole 61a.

[0032] The material lifter 62 is for lifting the steel sheet 2 above the die 61. The steel sheet 2 is sent downstream while being lifted by the material lifter 62. The material lifters 62 may be arranged on both sides of the pushing hole 61a and the punching hole 60a, and may lift both side portions of the steel sheet 2 in the width direction D3.

[0033] The material lifter 62 may have a lifter spring 62a stored in storage holes 60b, 61b provided in the lower die set 60 and the die 61, and a pin 62b that is biased upward by the lifter spring 62a and has at least a tip portion that protrudes upward from the storage holes 60b, 61b. The tip portion of the pin 62b biased by the lifter spring 62a is pressed against the underside of the steel sheet 2, thereby lifting the steel sheet 2.

[0034] The material stock guide 63 is for restricting the upward movement of the steel plate 2. The material stock guide 63 has overhanging portions 63a arranged so as to cover the upper sides of the steel plate 2, and the upper surface of the steel plate 2 is pressed against the lower surface of the overhanging portions 63a, thereby restricting the upward movement of the steel plate 2.

[0035] The lower die height post 64, together with an upper die height post 75 of the upper die 130 described below, is used to determine the bottom dead center of the punch 74. The lower die height post 64 may be erected on the upper surface of the lower die set 60. The lower die height post 64 may be arranged outside the die 61, material lifter 62, and material stock guide 63 in the width direction D3 of the steel plate 2.

[0036] As shown in FIG. 4 , the upper mold 130 includes an upper die set 70 , a plate holder 71 , a plate holder suspension bolt 72 , a plate holder spring 73 , a punch 74 , and an upper mold height post 75 .

[0037] An upper die set 70 is disposed above the upper mold 130. A plate holder 71 is suspended from the upper die set 70 by plate holder suspension bolts 72. The plate holder suspension bolts 72 are attached to the upper die set 70 so as to allow the plate holder 71 to be displaced in a direction approaching the upper die set 70. A plate holder spring 73 biases the plate holder 71 downward.

[0038] The plate holder 71 is pressed against the steel plate 2. The recess 50 and the vent hole 51 may be provided in the plate holder 71. By providing the recess 50 and the vent hole 51 in the plate holder 71, unnecessary spreading of the adhesive 140 can be more reliably suppressed, and the risk of the adhesive 140 getting into unintended areas can be more reliably reduced.

[0039] The plate holder 71 may have a base 710 and a surface layer 711 that is detachably attached to the base 710 and pressed against the steel plate 2, the recess 50 may be provided in the surface layer 711, and at least a portion of the vent hole 51 may be provided in the base 710. Providing the recess 50 in the detachable surface layer 711 makes it easy to attach and detach the portion where the recess 50 is provided, improving maintainability. Furthermore, it is preferable that the recess 50 is positioned and sized to just cover each individual adhesive 140 attached to the steel plate 2. Variations may occur in the amount of adhesive 140 attached and the way it spreads on the steel plate 2. Providing the recess 50 in the detachable surface layer 711 makes it easy to adjust the position and size of the recess 50, thereby flexibly responding to variations in the amount of adhesive 140 attached and the way it spreads.

[0040] The surface layer 711 may be configured to be attached to the base 710 and detachable from the base 710 without destroying the base 710 and / or the surface layer 711, for example by fastening, engaging, or other methods.

[0041] The base 710 may have a stripper plate 710a arranged on top of the plate holder 71 and a stripper 710b fixed to the lower surface of the stripper plate 710a. The surface layer 711 may have a stripper block 711a attached to the lower surface of the stripper 710b. A plate holder spring 73 may be connected to the stripper plate 710a. The plate holder suspension bolt 72 may pass through the stripper plate 710a and reach the stripper 710b. The stripper block 711a may be at least partially arranged on the outer periphery of the punch 74.

[0042] In the illustrated embodiment, the recess 50 is provided in the stripper block 711a, and the vent 51 is provided in the stripper block 711a and the stripper 710b. The vent 51 extends upward from the back wall 50a of the recess 50 and opens in the upper surface of the stripper 710b. The space above the stripper 710b is in communication with the outside (atmosphere) of the upper mold 130.

[0043] The punch 74 protrudes downward from the lower surface of the upper die set 70. The punch 74 is fixedly provided with respect to the upper die set 70. In other words, the above-mentioned sheet holder 71 is provided so as to be displaceable relative to the punch 74. In this embodiment, the punch 74 constitutes a punching die that punches out the steel sheet 2 after the sheet holder 71 is pressed against the steel sheet 2.

[0044] The upper die height post 75, together with the lower die height post 64 of the lower die 131, is used to determine the bottom dead center of the punch 74. The upper die height post 75 protrudes downward from the lower surface of the upper die set 70. The upper die height post 75 may be arranged outside the stripper plate 710a, stripper block 711a, sheet presser suspension bolt 72, sheet presser spring 73, and punch 74 in the width direction D3 of the steel sheet 2. The upper die height post 75 may pass through the stripper 710b.

[0045] As shown in FIG. 4, the steel plate 2 is lifted by the material lifter 62 and intermittently sent downstream with the upper surface of the steel plate 2 pressed against the lower surface of the overhanging portion 63a.

[0046] When the punching unit 15 punches out the steel sheet 2, first, as shown in Fig. 5, the upper die 130 is lowered to a position where the steel sheet 2 is clamped between the sheet holder 71 and the die 61. At this time, the steel sheet 2 is lowered while the lifter spring 62a is compressed by the pressure of the sheet holder 71, and the steel sheet 2 is placed on the upper surface of the lower die 131 (die 61).

[0047] Next, the upper die 130 is further lowered as shown in Figure 6. At this time, the sheet presser spring 73 is compressed, so that the punch 74 is further lowered while leaving the sheet presser 71 on the steel sheet 2, and the punch 74 is pressed into the pressing hole 61a of the die 61 together with a part of the steel sheet 2. The steel sheet 2 is punched out by this pressing of the punch 74.

[0048] 4 to 6 show the upper die 130 and the lower die 131 in the pre-processing section 150 in Fig. 1. In the pre-processing section 150, scrap 3a is dropped through the punching holes 60a in the lower die set 60. In the outline punching section 151, which punches out the outline of the core thin plate 3 from the steel plate 2, the core thin plate 3 is dropped through the punching holes 60a in the lower die set 60.

[0049] After the scrap 3a or iron core thin plate 3 is dropped from the punching hole 60a, the upper die 130 is raised. At this time, the lifter spring 62a is restored to its original position, lifting the steel plate 2. That is, in the manufacturing apparatus 1 of this embodiment, the steel plate 2 is moved up and down as the iron core thin plate 3 is punched out from the steel plate 2.

[0050] Second Embodiment Next, Figure 7 is an explanatory diagram showing the adhesive application means 14 and upper die 130 in the manufacturing apparatus 1 for laminated cores 4 according to a second embodiment of the present invention. In the first embodiment, the adhesive 140 is applied to a plurality of positions on the yoke spaced apart from one another in the circumferential direction of the yoke. However, alternatively or additionally, the adhesive 140 may be applied to the teeth. Also, in the first embodiment, the adhesive 140 is applied to a number of positions fewer than the number of teeth, but the adhesive 140 may be applied to a number of positions on each of the yoke and teeth equal to or greater than the number of teeth.

[0051] In the first embodiment, the ventilation hole 51 is described as extending linearly along the separating direction D2 between the upper mold 130 and the lower mold 131. However, as shown in FIG. 7 , the ventilation hole 51 may include a horizontal hole 510 extending in a direction intersecting the separating direction D2 between the upper mold 130 and the lower mold 131.

[0052] A vertical hole 511 extending in the separation direction D2 of the upper mold 130 and the lower mold 131 may be interposed between the horizontal hole 510 and the recess 50. Alternatively, the horizontal hole 510 may be directly connected to the recess 50.

[0053] The horizontal holes 510 may extend in the width direction D3 of the steel sheet 2. Alternatively or additionally, the horizontal holes 510 may extend in the feed direction D1 of the steel sheet 2. The horizontal holes 510 may extend horizontally or may extend at an angle relative to the horizontal. Other configurations are the same as those in the first embodiment.

[0054] In the first and second embodiments, the adhesive application means 14 is described as applying the adhesive 140 to the upper surface of the steel plate 2. However, the adhesive application means 14 may apply the adhesive 140 to the lower surface of the steel plate 2. In this case, the recess 50 and the vent 51 may be provided in the lower mold 131, and the vent 51 may communicate the internal space of the recess 50 with the outside of the lower mold 131.

[0055] In the first and second embodiments, the plate holder 71 and the punching die (punch 74) are described as being provided in the upper die 130. However, the plate holder 71 and the punching die (punch 74) may be provided in the lower die 131.

[0056] A manufacturing method of a laminated core 4 according to an embodiment of the present invention includes manufacturing the laminated core 4 using the above-mentioned manufacturing apparatus 1 for manufacturing the laminated core 4. The manufacturing method of the laminated core 4 is the manufacturing apparatus 1 for punching out the core thin plates 3 of a predetermined shape from the steel plate 2 and manufacturing the laminated core 4 in which a predetermined number of the core thin plates 3 are stacked and bonded, and includes the steps of applying adhesive 140 to the portions 2a of the steel plate 2 corresponding to the core thin plates 3 by an adhesive application means 14, and punching the core thin plates 3 out of the steel plate 2 by a punching section 15 constituted by dies including an upper die 130 and a lower die 131 after the adhesive application means 14 has applied the adhesive 140, and the upper die 130 or the lower die 131 is provided with a recess 50 provided at a position corresponding to the portion 2a to which the adhesive 140 has been applied, and a vent 51 that connects the internal space of the recess 50 to the outside of the upper die 130 or the lower die 131.

[0057] Although the preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not limited to these examples. It is clear that a person skilled in the art to which the present invention pertains can conceive of various modifications and alterations within the scope of the technical ideas set forth in the claims, and it is understood that these also naturally fall within the technical scope of the present invention.

[0058] The invention described in this specification can also be described as follows: [1] A laminated core manufacturing device for punching out iron core thin plates of a predetermined shape from a steel plate and manufacturing a laminated core in which a predetermined number of the iron core thin plates are stacked and bonded, comprising: an adhesive application means for applying adhesive to portions of the steel plate corresponding to the iron core thin plates, and a punching section constituted by dies including an upper die and a lower die, for punching out the iron core thin plates from the steel plate after the adhesive has been applied by the adhesive application means, wherein the upper die or the lower die is provided with a recess provided at a position corresponding to the portion where the adhesive has been applied, and an air hole that connects the internal space of the recess to the outside of the upper die or the lower die. [2] The laminated core manufacturing device according to claim 1, wherein the upper die or the lower die has a sheet holder that is pressed against the steel plate, and a punching die that is displaceable relative to the sheet holder and punches out the steel plate after the sheet holder is pressed against the steel plate, and the recess and the vent hole are provided in the sheet holder. [3] The laminated core manufacturing device according to claim 2, wherein the sheet holder has a base and a surface layer that is detachably attached to the base and pressed against the steel plate, and the recess is provided in the surface layer, and at least a part of the vent hole is provided in the base. [4] The laminated core manufacturing device according to any one of claims 1 to 3, wherein the vent hole includes a horizontal hole that extends in a direction intersecting a direction separating the upper die and the lower die. [5] The laminated core manufacturing device according to any one of items 1 to 4, wherein the adhesive application means applies the adhesive to the upper surface of the steel plate, and the recessed portion and the vent hole are provided in the upper mold. [6] The laminated core manufacturing device according to any one of items 1 to 5, wherein the punching unit has a pre-processing unit that punches out portions of the steel plate other than the outer shape of the core thin plates in one or more processes, and an outer shape punching unit that punches out the outer shape of the core thin plates from the steel plate after punching by the pre-processing unit, and the recessed portion and the vent hole are provided in the pre-processing unit.[7] The laminated core manufacturing device according to claim 6, wherein the outer shape punching section is provided with a pressing section that spreads the adhesive when punching out the outer shape of the core thin plates. [8] A laminated core manufacturing method, comprising manufacturing the laminated core using the laminated core manufacturing device according to any one of claims 1 to 7.

[0059] REFERENCE SIGNS LIST 1: Manufacturing device 2: Steel plate 3: Iron core thin plate 4: Laminated iron core 14: Adhesive application means 140: Adhesive 15: Punching section 150: Pre-processing section 151: Outer shape punching section 50: Recess 51: Ventilation hole 510: Horizontal hole 52: Pressing section 71: Plate holder 710: Base 711: Surface layer 130: Upper mold 131: Lower mold

Claims

1. A laminated core manufacturing apparatus for punching out thin iron core plates of a predetermined shape from a steel plate and manufacturing a laminated core in which a predetermined number of the thin iron core plates are stacked and bonded together, comprising: an adhesive application means for applying adhesive to portions of the steel plate corresponding to the thin iron core plates; and a punching section composed of dies including an upper die and a lower die, for punching out the thin iron core plates from the steel plate after the adhesive has been applied by the adhesive application means, wherein the upper die or the lower die is provided with a recess provided at a position corresponding to the portion where the adhesive has been applied, and an air hole connecting the internal space of the recess to the outside of the upper die or the lower die.

2. The laminated core manufacturing device according to claim 1, wherein the upper die or the lower die has a plate clamp that is pressed against the steel plate, and a punching die that is arranged to be displaceable relatively to the plate clamp and punches out the steel plate after the plate clamp is pressed against the steel plate, and the recess and the air hole are provided in the plate clamp.

3. The laminated core manufacturing device according to claim 2, wherein the plate clamp has a base and a surface layer which is detachably attached to the base and pressed against the steel plate, the recess is provided in the surface layer, and at least a portion of the ventilation hole is provided in the base.

4. The laminated core manufacturing device according to claim 2, wherein the vent includes a horizontal hole extending in a direction intersecting the direction in which the upper die and the lower die are separated.

5. A laminated core manufacturing device as claimed in any one of claims 1 to 4, wherein the adhesive application means applies the adhesive to the upper surface of the steel plate, and the recess and the vent hole are provided in the upper mold.

6. A laminated core manufacturing device as claimed in any one of claims 1 to 4, wherein the punching section has a pre-processing section which punches out the portions of the core thin plates from the steel plate other than the outer shape thereof in one or more processes, and an outer shape punching section which punches out the outer shape of the core thin plates from the steel plate after punching by the pre-processing section, and the recesses and the ventilation holes are provided in the pre-processing section.

7. The laminated core manufacturing device according to claim 6, wherein the outer shape punching section is provided with a pressing section that spreads the adhesive when punching out the outer shape of the thin core plates.

8. A method for manufacturing a laminated core, comprising manufacturing the laminated core using the laminated core manufacturing apparatus according to any one of claims 1 to 4.

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