Manufacturing method of electromagnetic steel sheet and bonded laminated core

Abstract

This electromagnetic steel sheet has a chemical composition containing, in a unit of mass%, 2.5-3.9% of Si, 0.001-3.0% of Al, and 0.05-5.0% of Mn, the remaining portion being Fe and impurities, and has, on one or both surfaces, an insulating coating containing a curing accelerator.

Description

[Technical field]

[0001] The present invention relates to an electromagnetic steel sheet and a method for manufacturing a bonded laminated core. This application claims priority based on Patent Application No. 2021-068106, filed in Japan on April 14, 2021, the contents of which are incorporated herein by reference. [Background technology]

[0002] For example, a rotating electric machine used as an electric motor includes a laminated core. This laminated core is manufactured by punching a strip-shaped steel plate into a predetermined shape in several steps while intermittently feeding the strip-shaped steel plate, and stacking the obtained steel plate parts. The steel plate parts are fixed to each other by welding, bonding, crimping, etc., but among these, a fixing method by bonding has attracted attention from the viewpoint of effectively suppressing iron loss of the laminated core.

[0003] For example, Patent Document 1 listed below discloses a method for producing a metal sheet laminate by sequentially performing multiple press processes on a hoop material with press processing oil applied to one or both sides, applying an adhesive to one side of the hoop material, performing an outline punching process to obtain a metal sheet, and stacking and adhering a predetermined number of the metal sheets, in which a hardening accelerator is added to the press processing oil. According to this method for manufacturing a metal sheet laminate, by adding a hardening accelerator to the press processing oil, bonding between the metal sheets is achieved quickly and strongly without removing the press processing oil, and it is explained that this makes it possible to simplify the manufacturing process and reduce the size of the dies in the progressive die device, thereby improving product quality and productivity and reducing the size of the manufacturing equipment.

[0004] Furthermore, the following Patent Document 2 discloses a punching and laminating press method for punching steel plate parts of a predetermined shape from an intermittently fed strip steel plate and laminating the steel plate parts, the punching and laminating press method including a first application step of applying either an adhesive or a hardening accelerator for promoting hardening of the adhesive to the underside of the strip steel plate upstream of a press processing position where the steel plate parts are punched from the strip steel plate, and a second application step of applying the other of the adhesive and the hardening accelerator to the upper surface of the strip steel plate at the press processing position. It is explained that this punching and laminating press method makes it possible to significantly shorten the adhesive curing time by performing the first and second application processes, thereby increasing the productivity of cores manufactured by stacking multiple steel plate parts. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent No. 4648765 [Patent Document 2] Japanese Patent No. 6164029 Summary of the Invention [Problem to be solved by the invention]

[0006] According to the manufacturing method of the metal sheet laminate in the above-mentioned Patent Document 1, the metal sheets can be bonded quickly by using a hardening accelerator. Since the hardening accelerator is applied in a diluted state by adding press processing oil, if a higher hardening acceleration effect is required, the content of the hardening accelerator needs to be increased to a considerable amount. However, in this case, the proportion of the press processing oil is reduced, which may affect the punching workability when punching the metal sheets. In addition, the punching lamination press method of Patent Document 2 claims to be able to significantly shorten the curing time of the adhesive. However, even in this case, no consideration is given at all to the effect of press oil, which is essential for punching, on the curing accelerator.

[0007] In this way, in order to further increase the productivity of bonded laminated cores, it is necessary to more effectively utilize the lubricating function of the press processing oil when punching the steel sheets, and the hardening accelerator when bonding the steel sheets to promote the hardening of the adhesive. However, this is difficult to achieve with conventional methods for manufacturing bonded laminated cores, and it has sometimes been difficult to achieve both high adhesive strength and high productivity.

[0008] The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide an electromagnetic steel sheet and a method for manufacturing a bonded laminated core that can achieve higher productivity while ensuring sufficient adhesive strength when manufacturing a bonded laminated core. [Means for solving the problem]

[0009] In order to solve the above problems, the present invention employs the following means. (1) An electrical steel sheet according to one aspect of the present invention comprises: Chemical composition, in mass%, Silicon: 2.5% to 3.9% Al: 0.001% to 3.0% Mn: 0.05% to 5.0% Remainder: Fe and impurities Contains An insulating coating containing a hardening accelerator is formed on one or both sides. And, The curing accelerator is sealed in the insulating coating in a dry state. There are. According to the magnetic steel sheet described in (1) above, the hardening accelerator added to the insulating coating is dried in advance and is enclosed within the insulating coating. Therefore, when this magnetic steel sheet is used to manufacture a bonded laminated core, mixing with the press processing oil applied before press processing is suppressed. Therefore, when the steel sheet components are laminated and bonded, the hardening accelerator can be mixed with the adhesive while maintaining a high concentration, so that high adhesive strength can be achieved early. Therefore, it is possible to obtain higher productivity while ensuring sufficient adhesive strength.

[0010] (2) In the electrical steel sheet according to (1), The cure accelerator may include an active ingredient that promotes anaerobic cure selected from titanium, chromium, manganese, iron, cobalt, nickel, copper, zinc, silver, vanadium, molybdenum, ruthenium, and combinations thereof. The active ingredient for accelerating anaerobic hardening is selected from titanium, chromium, manganese, iron, cobalt, nickel, copper, zinc, silver, vanadium, molybdenum, ruthenium, and combinations thereof. It may be preferably selected from copper, iron, vanadium, cobalt, chromium, silver, and manganese, and combinations thereof. It may be preferably copper, iron, vanadium, cobalt, and chromium, and combinations thereof. It is preferably provided in the form of a metal oxide or salt. It is preferably one or a combination of two or more selected from vanadium acetylacetonate, vanadyl acetylacetonate, vanadyl stearate, vanadium propoxide, vanadium butoxide, vanadium pentoxide, cobalt naphthenate, manganese naphthenate, copper hexanoate, copper(II) bis(2-ethylhexanoate), and the like. According to the magnetic steel sheet described in (2) above, when the magnetic steel sheet is used to manufacture a bonded laminated core, the anaerobic adhesive hardens quickly and completely, which makes the magnetic steel sheet particularly suitable for short-time manufacturing and manufacturing that requires suppression of outgassing, thereby improving productivity.

[0011] (3) A method for producing a bonded laminated core according to one aspect of the present invention includes the steps of: A method for manufacturing an adhesive laminated core, comprising the steps of: pressing a strip of steel plate having press working oil applied to one or both sides thereof; applying an adhesive to one side of the strip of steel plate to obtain a plurality of steel plate parts; and laminating and bonding the steel plate parts together, the method comprising the steps of: The electrical steel sheet according to (1) or (2) above is used as the strip steel sheet. According to the method for manufacturing a bonded laminated core described in (3) above, the hardening accelerator added to the insulating coating is dried in advance and is sealed in the insulating coating, so that it is prevented from mixing with the press processing oil applied before the press processing. Therefore, when the steel plate parts are laminated and bonded, the hardening accelerator can be mixed with the adhesive while maintaining a high concentration, so that high adhesive strength can be achieved early. Therefore, it is possible to obtain higher productivity while ensuring sufficient adhesive strength.

[0012] (4) In the method for producing an adhesive laminated core described in (3) above, the following may be performed: The steel plate components include a first steel plate component and a second steel plate component, A first step of preparing the first steel plate component having the insulating coating on a first surface side; a second step of preparing the second steel plate component having, on a second surface side, the insulating coating, the press working oil applied on the insulating coating, and the adhesive applied on the press working oil; a third step of overlapping and adhering the first steel plate part and the second steel plate part so that the first surface and the second surface face each other; has. According to the method for manufacturing a bonded laminated core described in (4) above, the hardening accelerator is dried and enclosed in the insulating coating before the third step, so that it is prevented from mixing with the press processing oil. Therefore, when the first steel sheet part and the second steel sheet part are superimposed and bonded in the third step, the hardening accelerator can be mixed with the adhesive while maintaining a high concentration.

[0013] (5) In the method for producing an adhesive laminated core described in (3) above, the following may be performed: The steel plate parts include a third steel plate part and a fourth steel plate part, a fourth step of preparing the third steel plate component having the insulating coating and the press working oil applied on the insulating coating on a third surface side; a fifth step of preparing the fourth steel plate component having, on a fourth surface side, the insulating coating, the press working oil applied on the insulating coating, and the adhesive applied on the press working oil; A sixth step of overlapping and adhering the third steel plate part and the fourth steel plate part so that the third surface and the fourth surface face each other; has. According to the method for manufacturing a bonded laminated core described in (5) above, the hardening accelerator is dried and enclosed in the insulating coating before the sixth step, so that it is prevented from mixing with the press processing oil. Therefore, when the third steel sheet part and the fourth steel sheet part are superimposed and bonded in the sixth step, the hardening accelerator can mix with the adhesive while maintaining a high concentration.

[0014] (6) In the bonded laminated core manufacturing method according to any one of the above (3) to (5), the bonded laminated core may be a stator for a rotating electric machine. According to the adhesive laminated core manufacturing method described in (6) above, higher productivity can be achieved while ensuring sufficient adhesive strength, making it possible to manufacture stators for rotating electric machines that have high performance but low manufacturing costs. Effect of the Invention

[0015] According to the above-mentioned aspects of the present invention, it is possible to provide an electromagnetic steel sheet and a method for manufacturing a bonded laminated core, which can ensure sufficient adhesive strength and achieve higher productivity when manufacturing a bonded laminated core. [Brief description of the drawings]

[0016] [Figure 1] 1 is a cross-sectional view of a rotating electric machine including a stator bonded laminated core manufactured in accordance with each embodiment of the present invention. [Diagram 2] FIG. 2 is a side view of the stator bonded laminated core. [Diagram 3] 1 is a side view of a bonded laminated core manufacturing apparatus according to a first embodiment of the present invention. [Figure 4]4 is a flowchart for explaining a method for manufacturing a bonded laminated core according to the embodiment. [Diagram 5] 10 is a flowchart for explaining a modified example of the bonded laminated core manufacturing method. [Figure 6] FIG. 5 is a side view of a bonded laminated core manufacturing apparatus according to a second embodiment of the present invention. [Figure 7] 4 is a flowchart for explaining a method for manufacturing a bonded laminated core according to the embodiment. [Figure 8] 10 is a flowchart for explaining a modified example of the bonded laminated core manufacturing method. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, the electromagnetic steel sheets and the bonded laminated core manufacturing method according to each embodiment and each modification of the present invention will be described with reference to the drawings. Before that, the bonded laminated core for a stator (bonded laminated core, stator for a rotating electric machine) manufactured in each embodiment and each modification will be described with reference to Figs. 1 and 2.

[0018] [Adhesive laminated core for stator] Fig. 1 is a cross-sectional view of a rotating electrical machine 10 including a stator adhesive laminated core 21 manufactured in each embodiment. Fig. 2 is a side view of the stator adhesive laminated core 21. 1 is an electric motor, specifically an AC motor, more specifically a synchronous motor, and even more specifically a permanent magnet field type motor. This type of motor is preferably used in, for example, electric vehicles.

[0019] 1, the rotating electric machine 10 includes a stator 20, a rotor 30, a case 50, and a rotating shaft 60. The stator 20 and the rotor 30 are housed in the case 50. The stator 20 is fixed within the case 50. 1, the rotating electric machine 10 is an inner rotor type in which the rotor 30 is located radially inside the stator 20. However, the rotating electric machine 10 may be an outer rotor type in which the rotor 30 is located outside the stator 20. Also, here, the rotating electric machine 10 is illustrated as a 12-pole, 18-slot three-phase AC motor. However, the number of poles, the number of slots, the number of phases, etc. can be changed as appropriate. The rotating electric machine 10 can rotate at a rotation speed of 1000 rpm by applying an excitation current with an effective value of 10 A and a frequency of 100 Hz to each phase, for example.

[0020] The stator 20 includes a stator adhesive laminated core 21 and a winding (not shown). The stator adhesive laminated core 21 includes an annular core back portion 22 and a plurality of teeth portions 23. Hereinafter, the direction of the central axis O of the stator adhesive laminated core 21 (or the core back portion 22) will be referred to as the axial direction, the radial direction (direction perpendicular to the central axis O) of the stator adhesive laminated core 21 (or the core back portion 22) will be referred to as the radial direction, and the circumferential direction (direction going around the central axis O) of the stator adhesive laminated core 21 (or the core back portion 22) will be referred to as the circumferential direction.

[0021] The core back portion 22 is formed in an annular shape when viewed in a plan view of the stator 20 in the axial direction. The multiple teeth portions 23 protrude radially inward from the inner circumference of the core back portion 22. The multiple teeth portions 23 are arranged at equal angular intervals in the circumferential direction. In the example of FIG. 1, 18 teeth portions 23 are provided at central angle intervals of 20 degrees about the central axis O. The multiple teeth portions 23 are formed to have the same shape and size as one another. Therefore, the multiple teeth portions 23 have the same thickness dimension as one another. The winding is wound around the teeth portion 23. The winding may be a concentrated winding or a distributed winding.

[0022] The rotor 30 is disposed radially inside the stator 20 (the stator adhesive laminated core 21). The rotor 30 includes a rotor core 31 and a plurality of permanent magnets 32. The rotor core 31 is formed in an annular (circular) shape and is disposed coaxially with the stator 20. A rotating shaft 60 is disposed within the rotor core 31. The rotating shaft 60 is fixed to the rotor core 31. The multiple permanent magnets 32 are fixed to the rotor core 31. In the example of Fig. 1, a pair of the permanent magnets 32 forms one magnetic pole. The multiple pairs of permanent magnets 32 are arranged at equal angular intervals in the circumferential direction. In the example of Fig. 1, 12 pairs of permanent magnets 32 (24 in total) are provided at central angle intervals of 30 degrees around the central axis O.

[0023] In the example of FIG. 1, an embedded magnet type motor is used as the permanent magnet field type motor. A rotor core 31 is formed with a plurality of through holes 33 that pass through the rotor core 31 in the axial direction. The plurality of through holes 33 are provided corresponding to the arrangement of the plurality of permanent magnets 32. Each permanent magnet 32 ​​is fixed to the rotor core 31 while being arranged in the corresponding through hole 33. Each permanent magnet 32 ​​can be fixed to the rotor core 31 by, for example, bonding the outer surface of the permanent magnet 32 ​​to the inner surface of the through hole 33 with an adhesive. Note that a surface magnet type motor may be used as the permanent magnet field type motor instead of the embedded magnet type.

[0024] Both the stator adhesive laminated core 21 and the rotor core 31 are laminated cores. For example, the stator adhesive laminated core 21 is formed by laminating a plurality of electromagnetic steel sheets 40 in a lamination direction, as shown in FIG. The lamination thickness (total length along the central axis O) of each of the stator adhesive laminated core 21 and the rotor core 31 is, for example, 50.0 mm. The outer diameter of the stator adhesive laminated core 21 is, for example, 250.0 mm. The inner diameter of the stator adhesive laminated core 21 is, for example, 165.0 mm. The outer diameter of the rotor core 31 is, for example, 163.0 mm. The inner diameter of the rotor core 31 is, for example, 30.0 mm. However, these values ​​are merely examples, and the lamination thickness, outer diameter, and inner diameter of the stator adhesive laminated core 21 and the lamination thickness, outer diameter, and inner diameter of the rotor core 31 are not limited to these values. Here, the inner diameter of the stator adhesive laminated core 21 is based on the tip of the teeth portion 23 in the stator adhesive laminated core 21. In other words, the inner diameter of the stator adhesive laminated core 21 is the diameter of a virtual circle inscribed in the tip of all the teeth portions 23.

[0025] Each of the electromagnetic steel sheets 40 forming the stator adhesive laminated core 21 and the rotor core 31 is formed, for example, by punching a strip-shaped steel sheet as a base material. A known electromagnetic steel sheet can be used as the electromagnetic steel sheet 40. The chemical composition of the electromagnetic steel sheet 40 is shown below in mass %, and contains 2.5% to 3.9% Si by mass %. By setting the chemical composition within this range, the yield strength of each of the electromagnetic steel sheets 40 can be set to 380 MPa or more and 540 MPa or less.

[0026] Silicon: 2.5% to 3.9% Al: 0.001% to 3.0% Mn: 0.05% to 5.0% Remainder: Fe and impurities

[0027] In this embodiment, a non-oriented electromagnetic steel sheet is used as the electromagnetic steel sheet 40. As the non-oriented electromagnetic steel sheet, a non-oriented electrical steel strip according to JIS C2552:2014 can be used. However, a directional electromagnetic steel sheet may be used as the electromagnetic steel sheet 40 instead of the non-oriented electromagnetic steel sheet. In this case, as the directional electromagnetic steel sheet, a directional electrical steel strip according to JIS C2553:2012 can be used.

[0028] In order to improve the workability of the laminated core and the iron loss of the laminated core, one or both sides of the magnetic steel sheet 40 are coated with a phosphate-based insulating coating. Examples of the material that can be used to form the insulating coating include (1) inorganic compounds, (2) organic resins, and (3) mixtures of inorganic compounds and organic resins. Examples of inorganic compounds include (1) composites of dichromate and boric acid, and (2) composites of phosphate and silica. Examples of organic resins include epoxy resins, acrylic resins, acrylic styrene resins, polyester resins, silicone resins, and fluorine resins.

[0029] A hardening accelerator is added to the insulating coating of each embodiment and each modified example. The hardening accelerator is dried in advance before addition by heating or blowing air into the liquid hardening accelerator. The dried hardening accelerator is added to a treatment liquid for forming the insulating coating, and then the insulating coating is formed. The hardening accelerator that is dried in advance and enclosed in the insulating coating is prevented from mixing with the press processing oil applied before the press processing. Therefore, when the steel plate components are laminated and bonded, the hardening accelerator can be mixed with the adhesive while maintaining a high concentration, so that high adhesive strength can be developed early. Therefore, it is possible to obtain higher productivity while ensuring sufficient adhesive strength. The insulating coating can be formed by applying a treatment liquid (containing a hardening accelerator) for forming the insulating coating to the surface of the electrical steel sheet, for example, by a roll coater, and then baking the applied liquid in a heating furnace. The preferred amount of the treatment liquid to be applied in the step of forming the insulating coating is 0.4 g / m on average. 2 ~2.0g / m 2 The sheet temperature of the electrical steel sheet in the heating furnace may be within a range of 140° C. to 330° C. The baking time of the electrical steel sheet in the heating furnace may be within a range of 15 seconds to 60 seconds. In addition, when preparing a treatment liquid containing a compound having a curing-accelerating effect, the content of the compound per 100 parts by mass of water and solvent may be set within a range of 0.2 parts by mass to 20 parts by mass. By setting the content of the compound in the treatment liquid within this range, the content of the compound in the insulating coating of the solid body formed using this treatment liquid can be set to 0.3 wt% to 80 wt%.

[0030] When an anaerobic adhesive is used as the adhesive, the curing accelerator may contain an active ingredient that promotes anaerobic curing selected from titanium, chromium, manganese, iron, cobalt, nickel, copper, zinc, silver, vanadium, molybdenum, ruthenium, and combinations thereof. In this case, when the adhesive laminated core is manufactured using this magnetic steel sheet, the curing of the anaerobic adhesive proceeds quickly and completely. Therefore, it is extremely excellent in manufacturing that requires short manufacturing times and suppression of outgassing, and can improve productivity.

[0031] The active ingredient for promoting anaerobic hardening is selected from titanium, chromium, manganese, iron, cobalt, nickel, copper, zinc, silver, vanadium, molybdenum, ruthenium, and combinations thereof. Preferably, it may be selected from copper, iron, vanadium, cobalt, chromium, silver, and manganese, and combinations thereof. Desirably, it may be copper, iron, vanadium, cobalt, and chromium, and combinations thereof. Desirably, it is provided in the form of a metal oxide or salt. Preferably, it is one or a combination of two or more selected from vanadium acetylacetonate, vanadyl acetylacetonate, vanadyl stearate, vanadium propoxide, vanadium butoxide, vanadium pentoxide, cobalt naphthenate, manganese naphthenate, copper hexanoate, copper (II) bis(2-ethylhexanoate), and the like.

[0032] [First embodiment] A first embodiment of the present invention will be described below with reference to Fig. 3 and Fig. 4. Fig. 3 is a side view of a bonded laminated core manufacturing apparatus according to this embodiment. Fig. 4 is a flow chart for explaining a bonded laminated core manufacturing method according to this embodiment. As shown in FIG. 3, the bonded laminated core manufacturing apparatus 100 of this embodiment includes a strip steel plate supply section 110, a drive section (not shown), a press processing oil application section 130, a press processing section 140, an adhesive application section 150, and a laminate bonding section 160.

[0033] The strip steel sheet supplying section 110 supports a hoop material F wound with a strip steel sheet M, which is the raw material of the electromagnetic steel sheet (steel sheet part) 40, and sends out the strip steel sheet M toward the right side of the paper in FIG. 3. In the following description, the right side of the paper, which is the feeding direction of the strip steel sheet M, may be referred to as the downstream side, and the left side of the paper, which is the opposite direction, may be referred to as the upstream side. The strip steel sheet M sent downstream from the strip steel sheet supplying section 110 is a steel sheet having the above-mentioned chemical composition, and both sides (both the upper and lower sides) are covered with the above-mentioned insulating coating. The above-mentioned hardening accelerator is added to this insulating coating in advance. Therefore, in the strip steel sheet supplying section 110, the hardening accelerator is present on the upper and lower sides of the strip steel sheet M uniformly along these surfaces in a state of being dried in advance and being enclosed in the insulating coating.

[0034] The drive unit is disposed at position D between the strip steel sheet supply unit 110 and the press working oil application unit 130. The drive unit intermittently sends out the strip steel sheet M from the strip steel sheet supply unit 110 toward the press working oil application unit 130 to the right of the drawing. On the upper and lower surfaces of the strip steel sheet M sent out from the strip steel sheet supply unit 110, the hardening accelerator continues to be present uniformly along each surface in a state of being dried in advance and enclosed in an insulating coating.

[0035] The press working oil application section 130 includes an application roller 131 and an oil pan 132 . The oil pan 132 is disposed below the strip steel sheet M and directly below the application roller 131. The application roller 131 has an upper roller 131a and a lower roller 131b. The upper roller 131a is disposed directly above the strip steel sheet M, and by moving up and down, can be switched between a state in contact with and a state separated from the upper surface of the strip steel sheet M. The upper roller 131a can supply press processing oil to the upper surface of the strip steel sheet M by rolling while being in contact with the upper surface of the steel sheet M with press processing oil supplied from a press processing oil supply unit (not shown) permeating its outer circumferential surface. The lower roller 131b is disposed directly below the strip steel sheet M, and can be switched between a state in contact with and a state separated from the lower surface of the strip steel sheet M by moving up and down. The lower roller 131b can supply press processing oil to the underside of the strip steel sheet M by rolling while being in contact with the underside of the steel sheet M with the press processing oil supplied from the press processing oil supply unit permeating its outer circumferential surface. The oil pan 132 receives and collects excess press oil dripping from the upper roller 131a and the lower roller 131b, and returns it to the press oil supply section.

[0036] According to the press processing oil application section 130, by supplying press processing oil from the press processing oil supply section while the upper roller 131a is in contact with the upper surface of the strip steel plate M, a layer of press processing oil can be formed over the entire surface of the insulating coating on the upper surface of the strip steel plate M, while the strip steel plate M can be sent out downstream continuously or intermittently. Similarly, by supplying press processing oil from the press processing oil supply section while the lower roller 131b is in contact with the underside of the strip steel plate M, a layer of press processing oil can be formed over the entire surface of the insulating coating on the underside of the strip steel plate M, while the strip steel plate M is sent downstream continuously or intermittently.

[0037] Alternatively, by sandwiching the strip steel plate M between the upper roller 131a and the lower roller 131b, a layer of press processing oil can be formed over the entire surface of both the insulating coating on the upper surface of the strip steel plate M and the insulating coating on the lower surface of the strip steel plate M, while the strip steel plate M is sent downstream continuously or intermittently. In this way, by moving the positions of the upper roller 131a and the lower roller 131b up and down as needed, the press processing oil can be applied in three ways: only to the upper surface of the strip steel plate M, only to the lower surface of the strip steel plate M, or to both the upper and lower surfaces of the strip steel plate M.

[0038] In any of the above cases, the hardening accelerator on the upper and lower surfaces of the strip steel sheet M is sealed in a dry state in the insulating coating before the press oil is applied, so that the application of the press oil prevents the concentration from being diluted. Therefore, the concentration of the hardening accelerator on the upper surface of the strip steel sheet M after the press oil is applied is maintained unchanged from the time of the hoop material M. Similarly, the concentration of the hardening accelerator on the lower surface of the strip steel sheet M after the press oil is applied is also maintained unchanged from the time of the hoop material M. Therefore, the strip steel sheet M after passing through the press oil application section 130 is sent to the press processing section 140 while maintaining the concentration of the hardening accelerator on its upper and lower surfaces.

[0039] The press processing section 140 includes a first stage punching section 141 and a second stage punching section 142 . The first-stage punching section 141 is disposed downstream of the press oil application section 130 and has a male die 141a and a female die 141b. The male die 141a and the female die 141b are disposed coaxially along the vertical direction, and the strip steel sheet M is inserted between them. Thus, the male die 141a faces the upper surface of the strip steel sheet M, and the female die 141b faces the lower surface of the strip steel sheet M. Then, in a state where the delivery of the strip steel sheet M is temporarily stopped, the male die 141a is moved downward by a hydraulic mechanism (not shown) to reach the female die 141b, thereby performing the first punching process required to form the electromagnetic steel sheet 40 of the strip steel sheet M. At this time, since the press oil has been applied to the strip steel sheet M in advance, it can be punched without causing seizure or the like. After this punching process, the male die 141a is then moved upward and pulled out from the female die 141b, and the strip steel sheet M is again sent out toward the downstream side.

[0040] The second-stage punching section 142 is disposed downstream of the first-stage punching section 141 and has a male die 142a and a female die 142b. The male die 142a and the female die 142b are disposed coaxially along the vertical direction, and the strip steel sheet M after the first punching process is inserted between them. Thus, the male die 142a faces the upper surface of the strip steel sheet M, and the female die 142b faces the lower surface of the strip steel sheet M. Then, in a state where the delivery of the strip steel sheet M is again temporarily stopped, the male die 142a is moved downward by a hydraulic mechanism (not shown) to reach the female die 142b, thereby performing the second punching process required to form the electromagnetic steel sheet 40 of the strip steel sheet M. At this time, too, press processing oil is applied in advance to the upper and lower surfaces of the strip steel sheet M, so that the strip steel sheet M can be punched without causing seizure or the like. After this punching process, the male die 142a is then moved upward and pulled out from the female die 142b, and the strip steel sheet M is again sent out toward the downstream side. After passing through the press processing section 140 in this manner, the steel strip M still has high concentrations of hardening accelerator present on its upper and lower surfaces, and is sent as is to the adhesive application section 150.

[0041] The adhesive application section 150 is disposed downstream of the press processing section 140. The adhesive application section 150 includes an air compressor 151, a syringe 152, a nozzle 153, and a steel plate holder 154. Syringe 152 is a container for storing adhesive, and is connected between air compressor 151 and nozzle 153 via piping. When an anaerobic adhesive is used as the adhesive, "Arontight" (registered trademark) manufactured by Toagosei Co., Ltd. can be exemplified. When a 2-cyanoacrylate adhesive is used as the adhesive, "Aron Alpha" (registered trademark) manufactured by Toagosei Co., Ltd. can be exemplified. The nozzle 153 includes a plurality of needles whose discharge ports face upward. Each needle is disposed below the steel strip M. Therefore, the discharge port of each needle faces the lower surface of the steel strip M.

[0042] The steel plate holder 154 is disposed above the nozzle 153 (directly above each needle). Thus, the steel plate holder 154 faces the upper surface of the strip steel plate M. The steel plate holder 154 is pressed downward by a hydraulic mechanism (not shown) when the delivery of the strip steel plate M is temporarily stopped. As a result, the lower surface of the steel plate holder 154 comes into contact with the upper surface of the strip steel plate M and presses the strip steel plate M downward. This allows the height position of the strip steel plate M to be pressed down to the adhesive application position by the nozzle 153 and positioned. In this positioned state, the lower surface of the strip steel plate M is close to the discharge port of each needle.

[0043] Furthermore, in this positioned state, when the air compressor 151 is started to pump an appropriate amount of air into the syringe 152, the adhesive in the syringe 152 is sent to the nozzle 153. As a result, an appropriate amount of adhesive is discharged from each needle and applied to the underside of the strip steel plate M. Thereafter, the hydraulic mechanism raises the steel plate holder 154, thereby returning the height position of the strip steel plate M to its original height. Here, the adhesive is applied onto the surface of the press oil that covers the insulating coating on the underside of the strip steel sheet M. Although the press oil is liquid, the insulating coating itself is solid, so that the press oil is prevented from mixing with the hardening accelerator added to the insulating coating. Therefore, the hardening accelerator and the adhesive are kept separated from each other on the underside of the strip steel sheet M. As a result, the strip steel sheet M after passing through the adhesive application section 150 still has the hardening accelerator present on its upper and lower surfaces at a high concentration, and is sent to the lamination bonding section 160 as is.

[0044] The lamination bonding section 160 is disposed downstream of the adhesive application section 150. The lamination bonding section 160 includes a male outer periphery punching die 161, a female outer periphery punching die 162, a spring 163, and a heater 164. The outer periphery punching male die 161 is a cylindrical die with a circular bottom surface, and the upper end of the die is connected to the lower end of the spring 163. The outer periphery punching male die 161 is supported by the spring 163 and can move up and down together with the spring 163. The outer periphery punching male die 161 has an outer diameter substantially the same as that of the stator adhesive laminated core 21.

[0045] The outer periphery punching female die 162 is a die having a cylindrical internal space, and has an inner diameter dimension that is approximately the same as the outer diameter dimension of the stator bonded laminated core 21 . The heater 164 is integrally built into the outer periphery punching female die 162. The heater 164 heats the periphery of each of the electromagnetic steel sheets (steel sheet components) 40 stacked inside the outer periphery punching female die 162. When a heat-curing type adhesive is used as the adhesive, the adhesive cures when it receives heat from the heater 164. On the other hand, when a room temperature curing type adhesive is used as the adhesive, the adhesive cures at room temperature without the need for heating.

[0046] According to the laminated adhesive section 160, while the feeding of the strip-shaped steel sheet M is temporarily stopped, the outer periphery punching male die 161 is lowered to sandwich the strip-shaped steel sheet M between it and the outer periphery punching female die 162, and the outer periphery punching male die 161 is further pushed into the outer periphery punching female die 162, thereby obtaining an electromagnetic steel sheet 40 whose periphery has been punched out from the strip-shaped steel sheet M. This punched out electromagnetic steel sheet 40 is stacked on the top surface of other electromagnetic steel sheets 40 that have been previously punched out and stacked and bonded inside the outer periphery punching female die 162, and is further subjected to a pressure from the outer periphery punching male die 161 and heat from a heater 164. At this time, the pressure applied to the electromagnetic steel sheet 40 from the outer periphery punching male die 161 is always kept constant by the biasing force of the spring 163.

[0047] The pressure applied at this time causes the adhesive on the underside of the currently punched electromagnetic steel sheet 40 to mix with at least one of the hardening accelerator in the insulating coating on the upper surface of the other electromagnetic steel sheet 40 whose outer periphery has been previously punched, and the hardening accelerator in the insulating coating on the underside of the currently punched electromagnetic steel sheet 40, and harden instantaneously. As a result, the currently punched electromagnetic steel sheet 40 is adhered and fixed to the upper surface of the previously punched electromagnetic steel sheet 40. By repeating these steps of outer periphery punching, pressurizing, and heating a number of times corresponding to the number of laminated electromagnetic steel sheets 40, an adhesive laminated core 21 for a stator is formed in the outer periphery punching female die 162.

[0048] 3, the female die 141b, the female die 142b, the nozzle 153, the outer periphery punching female die 162, and the heater 164 are fixed on a common fixed base 171. Therefore, the relative positions of the female die 141b, the female die 142b, the nozzle 153, the outer periphery punching female die 162, and the heater 164 are fixed in the horizontal and vertical directions. Similarly, the male die 141a, the male die 142a, the steel plate holder 154, and the outer periphery punching male die 161 are also fixed to the lower surface of a common movable base 172. Therefore, the relative positions of the male die 141a, the male die 142a, the steel plate holder 154, and the outer periphery punching male die 161 in the horizontal and vertical directions are fixed.

[0049] The drive unit sends out the strip steel sheet M downstream and, when it is temporarily stopped, lowers the movable base 172, thereby simultaneously punching out the outer periphery of the electromagnetic steel sheet 40, stacking and bonding, applying adhesive to the position of the electromagnetic steel sheet 40 where the outer periphery will next be punched in the strip steel sheet M, the second punching process at the position of the strip steel sheet M where the adhesive will next be applied, and the first punching process at the position of the strip steel sheet M where the second punching process will next be performed. Next, the movable base 172 is raised and retracted above the strip steel sheet M, and then the drive unit sends out the strip steel sheet M a predetermined distance downstream again and pauses again. In this state, the movable base 172 is lowered again and processing is continued at each position. In this way, the process of moving the movable base 172 up and down during pauses while intermittently sending the strip steel sheet M by the drive unit is repeated, thereby manufacturing the stator adhesive laminated core 21.

[0050] A method for manufacturing a bonded laminated core using the bonded laminated core manufacturing apparatus 100 having the above-described configuration will be described below with reference to Fig. 4. In this embodiment, an example will be shown in which an insulating coating containing a hardening accelerator is formed on the top and bottom surfaces of a strip-shaped steel plate M, a press processing oil is applied only to the bottom surface of the strip-shaped steel plate M, and an adhesive is applied only to the bottom surface of the strip-shaped steel plate M. First, as shown in FIG. 4, the adhesive laminated core manufacturing method of this embodiment includes a steel plate feeding process S1, a processing oil application process S2, a first punching process S3, a second punching process S4, an adhesive application process S5, a third punching and stacking process S6, a laminate number confirmation process S7, and a removal process S8.

[0051] In the steel plate delivery process S1, the strip steel plate M is delivered downstream from the hoop material F. The hardening accelerator is added to both the insulating coating i1 covering the upper surface of the strip steel plate M and the insulating coating i2 covering the lower surface of the strip steel plate M. For ease of explanation, the reference characters i1 and i2 are used to distinguish the insulating coatings on the upper and lower surfaces of the strip steel plate M, but these insulating coatings i1 and i2 have the same composition and thickness. In the subsequent processing oil application step S2, the lower roller 131b applies press processing oil b2 only to the lower surface of the strip steel sheet M. As a result, a layer of press processing oil b2 is formed that covers the entire surface of the insulating coating i2. At this time, since the hardening accelerator is held within the solid insulating coating i2, it does not mix with the press processing oil b2 and its concentration does not decrease, but maintains almost its original state.

[0052] In the subsequent first punching process S3, the first punching of the strip steel sheet M is performed by the first-stage punching section 141. At this time, since the press processing oil b2 has been applied to the strip steel sheet M in advance, defects in the press processing such as seizure between the male die 141a and the female die 141b do not occur. In the subsequent second punching process S4, the second punching of the strip steel sheet M is performed by the second-stage punching section 142. At this time as well, since the press processing oil b2 has been applied in advance to the strip steel sheet M, defects in the press processing such as seizure between the male die 142a and the female die 142b do not occur. By the above-mentioned first punching process S3 and second punching process S4, the core back portion 22 and the teeth portion 23 shown in FIG. 1 are formed in the strip-shaped steel plate M, except for the outer shape portion.

[0053] In the subsequent adhesive application process S5, adhesive c discharged from a nozzle 153 is applied to the lower surface of the strip steel sheet M with press processing oil b2 interposed therebetween. At this time, adhesive c is applied in the form of dots having a predetermined thickness and a predetermined diameter. At this point, adhesive c is in a liquid state because it has not yet been mixed with a hardening accelerator.

[0054] In the subsequent third punching and lamination step S6, the electromagnetic steel sheet 40, the periphery of which has been punched out from the strip-shaped steel sheet M by the outer periphery punching male die 161, is laminated on the upper surface of the other electromagnetic steel sheet 40 that has been previously punched out. An insulating coating i1 to which a hardening accelerator has been added is formed on the upper surface of the other electromagnetic steel sheet 40. The electromagnetic steel sheet 40 that has been punched out this time is laminated on top of this and heated while being pressurized. Then, the adhesive c on the lower surface of the electromagnetic steel sheet 40 that has been punched out this time mixes with the hardening accelerator in the insulating coating i1 on the upper surface of the other electromagnetic steel sheet 40 that has been previously punched out. At the same time, the adhesive c displaces the press processing oil b2 on the lower surface of the electromagnetic steel sheet 40 that has been punched out this time and also mixes with the hardening accelerator in the insulating coating i2. In this way, the adhesive c instantly hardens while mixing with the hardening accelerator contained in both the insulating coatings i1 and i2. At this time, the hardening accelerator can be mixed with the adhesive c while maintaining its concentration, so that the hardening acceleration effect can be fully exerted.

[0055] By sequentially repeating the above steps, a predetermined number of electromagnetic steel sheets 40 are laminated and bonded together, and the bonded laminated core 21 for the stator is completed. That is, in the stacking number confirmation step S7, it is determined whether or not the number of stacked electromagnetic steel sheets 40 has reached a predetermined number. As a result, if it has not reached that number (determination: NO), the flow returns to the steel sheet delivery step S1, and the steel sheet delivery step S1 to the third punching and stacking step S6 are repeated again. On the other hand, if the predetermined number has been reached in the stacking number confirmation step S7 (determination: YES), the flow proceeds to the removal step S8. In the subsequent removal step S8, the completed bonded laminated core 21 for a stator is removed from the outer periphery punching female die 162, thereby completing all steps of the bonded laminated core manufacturing method. In the completed stator adhesive laminated core 21, the insulating coatings i1 and i2 ensure high insulating performance, and the hardening accelerator contained in these insulating coatings i1 and i2 ensures high adhesive strength at an early stage. Here, the insulating performance required for the stator adhesive laminated core 21 is, for example, an interlayer resistance value of 10 Ω-cm 2 The same applies to the other embodiments and modifications described below.

[0056] The main points of the bonded laminated core manufacturing method using the bonded laminated core manufacturing apparatus 100 described above will be summarized below. (1) The electrical steel sheet 40 (strip steel sheet M) of this embodiment contains the following chemical composition in unit mass %. Silicon: 2.5% to 3.9% Al: 0.001% to 3.0% Mn: 0.05% to 5.0% Remainder: Fe and impurities Insulating coatings i1, i2 containing a hardening accelerator are formed on both sides of the electromagnetic steel sheet 40 (strip-shaped steel sheet M). Note that the present invention is not limited to the case where both insulating coatings i1, i2 are formed, and only one of the insulating coatings i1, i2 (one side) may be formed. According to the electromagnetic steel sheet 40 described in (1) above, when the electromagnetic steel sheet 40 is used to manufacture the stator bonded laminated core 21, the hardening accelerator added to the insulating coatings i1, i2 is dried in advance and is sealed in the insulating coatings i1, i2, so that it is prevented from mixing with the press processing oil b2 applied before the press processing. Therefore, when the electromagnetic steel sheets 40 are laminated and bonded, the hardening accelerator can be mixed with the adhesive c while maintaining a high concentration, so that high adhesive strength can be developed early. Therefore, it is possible to obtain higher productivity while ensuring sufficient adhesive strength.

[0057] (2) In the electrical steel sheet 40 described in (1) above, the hardening accelerator may contain an active ingredient that promotes anaerobic hardening, selected from titanium, chromium, manganese, iron, cobalt, nickel, copper, zinc, silver, vanadium, molybdenum, ruthenium, and combinations thereof. According to the electromagnetic steel sheet 40 described in (2) above, when a plurality of such electromagnetic steel sheets 40 are laminated and bonded with an anaerobic adhesive to manufacture the bonded laminated core 21 for a stator, the hardening of the anaerobic adhesive proceeds quickly and completely. Therefore, it is extremely excellent in manufacturing that requires short manufacturing times and suppression of outgassing, and can improve productivity.

[0058] (3) The adhesive laminated core manufacturing method of this embodiment is a method for manufacturing an adhesive laminated core 21 for a stator by pressing a strip-shaped steel plate M having press processing oil b2 applied to one side thereof, applying adhesive c to one side of the strip-shaped steel plate M to obtain a plurality of steel plate parts 40, and stacking and bonding each of the steel plate parts 40, in which the electromagnetic steel plate 40 described above in (1) or (2) is used as the strip-shaped steel plate M. According to the method for manufacturing a bonded laminated core described in (3) above, the hardening accelerator added to the insulating coatings i1, i2 is dried in advance and is enclosed within the insulating coatings i1, i2, so that mixing with the press processing oil b2 applied before pressing is suppressed. Therefore, when the magnetic steel sheets 40 are laminated and bonded, the hardening accelerator can be mixed with the adhesive c while maintaining a high concentration, so that high adhesive strength can be achieved early. Therefore, it is possible to obtain higher productivity while ensuring sufficient adhesive strength.

[0059] (4) In the method for producing an adhesive laminated core described in (3) above, the following may be performed: Each electromagnetic steel sheet 40 includes an electromagnetic steel sheet (first steel sheet component) 40 that has been punched out first and an electromagnetic steel sheet (second steel sheet component) 40 that has been punched out later. The adhesive laminated core manufacturing method includes a first step of preparing an electromagnetic steel sheet (first steel sheet component) 40 that has an insulating coating i1 on an upper surface (first surface), a second step of preparing an electromagnetic steel sheet (second steel sheet component) 40 that has an insulating coating i2, a press processing oil b2 applied on the insulating coating i2, and an adhesive c applied on the press processing oil b2 on a lower surface (second surface), and a third step of overlapping and bonding the electromagnetic steel sheet (first steel sheet component) 40 that has been punched out first and the electromagnetic steel sheet (second steel sheet component) 40 that has been punched out later, so that the upper surface (first surface) and the lower surface (second surface) face each other. According to the method for manufacturing a bonded laminated core described in (4) above, the hardening accelerator is dried and enclosed in the insulating coatings i1, i2 before the third step, so that it is prevented from mixing with the press processing oil i2. Therefore, when the electromagnetic steel sheet (first steel sheet component) 40 punched first and the electromagnetic steel sheet (second steel sheet component) 40 punched later are overlapped and bonded in the third step, the hardening accelerator can mix with the adhesive c while maintaining a high concentration.

[0060] In the above embodiment, the press working oil b2 is applied only to the lower surface of the strip steel plate M, but the present invention is not limited to this embodiment, and the press working oil b2 may be applied to both the upper and lower surfaces of the strip steel plate M. This modification will be described below with reference to Fig. 5. In this modification, an insulating coating i1 to which a hardening accelerator has been added is formed on the upper surface of the strip steel plate M, an insulating coating i2 to which a hardening accelerator has been added is formed on the lower surface of the strip steel plate M, the press working oil b1 is applied to the upper surface of the strip steel plate M, the press working oil b2 is applied to the lower surface of the strip steel plate M, and the adhesive c is applied only to the lower surface of the strip steel plate M.

[0061] As shown in FIG. 5, the adhesive laminated core manufacturing method of this modified example includes a steel plate feeding process S1A, a processing oil application process S2A, a first punching process S3A, a second punching process S4A, an adhesive application process S5A, a third punching and stacking process S6A, a laminate number confirmation process S7A, and a removal process S8A.

[0062] The steel plate delivery step S1A is the same as the above-mentioned steel plate delivery step S1, and therefore a description thereof will be omitted. In the subsequent processing oil application step S2, press processing oil b1 is applied to the upper surface of the strip steel sheet M while the strip steel sheet M is sandwiched between the upper roller 131a and the lower roller 131b, and press processing oil b2 is applied to the lower surface of the strip steel sheet M. As a result, a layer of press processing oil b1 is formed to cover the entire surface of the insulating coating i1, and at the same time, a layer of press processing oil b2 is formed to cover the entire surface of the insulating coating i2. At this time, since the hardening accelerator is held within the solid insulating coatings i1 and i2, it does not mix with the press processing oils b1 and b2 to reduce its concentration, and it maintains almost its original state. For convenience of explanation, the symbols b1 and b2 are used to distinguish the press processing oils applied to the upper and lower surfaces of the strip steel sheet M, but these press processing oils b1 and b2 have the same components and application thickness.

[0063] The subsequent first punching step S3A is the same as the above-mentioned first punching step S3, and therefore a description thereof will be omitted. The subsequent second punching step S4A is the same as the above-mentioned second punching step S4, so a description thereof will be omitted. The subsequent adhesive application step S5A is the same as the adhesive application step S5, and therefore a description thereof will be omitted.

[0064] In the subsequent third punching and lamination step S6A, the electromagnetic steel sheet 40, the periphery of which has been punched out of the strip-shaped steel sheet M by the outer periphery punching male die 161, is laminated on the top surface of the other electromagnetic steel sheet 40 that has been previously punched out. On the top surface of the other electromagnetic steel sheet 40, an insulating coating i1 to which a hardening accelerator has been added and a film of press working oil b1 applied on the insulating coating i1 are formed. The electromagnetic steel sheet 40 that has been punched out this time is laminated on top of this and heated while being pressurized. Then, the adhesive c on the underside of the electromagnetic steel sheet 40 that has been punched out this time pushes aside the press working oil b1 on the top surface of the other electromagnetic steel sheet 40 that has been previously punched out, and mixes with the hardening accelerator in the insulating coating i1 underneath. At the same time, the adhesive c pushes aside the press working oil b2 on the underside of the electromagnetic steel sheet 40 that has been punched out this time, and also mixes with the hardening accelerator in the insulating coating i2. In this way, the adhesive c instantly hardens while mixing with the hardening accelerator contained in both insulating coatings i1 and i2. At this time, the hardening accelerator is able to mix with the adhesive c while maintaining its concentration, so it can fully exert its hardening acceleration effect.

[0065] By sequentially repeating the above steps, a predetermined number of electromagnetic steel sheets 40 are laminated and bonded together, and the bonded laminated core 21 for the stator is completed. The stack number confirmation step S7A is the same as the stack number confirmation step S7 described above, and therefore a description thereof will be omitted. Similarly, the removal step S8A is the same as the removal step S8 described above, and therefore the description thereof will be omitted.

[0066] [Second embodiment] Next, a second embodiment of the present invention will be described below with reference to Fig. 6 and Fig. 7. Fig. 6 is a side view of a bonded laminated core manufacturing apparatus according to this embodiment. Fig. 7 is a flow chart for explaining a bonded laminated core manufacturing method according to this embodiment. As shown in FIG. 6, the bonded laminated core manufacturing apparatus 200 of this embodiment includes a strip steel plate supply section 210, a drive section (not shown), a press processing oil application section 230, a press processing section 240, an adhesive application section 250, and a laminate bonding section 260.

[0067] The strip steel sheet supplying section 210 supports a hoop material F around which a strip steel sheet M, which is a material for the electromagnetic steel sheet (steel sheet part) 40, is wound, and sends out the strip steel sheet M toward the right side of the paper in FIG. 6. In the following description, the right side of the paper, which is the feeding direction of the strip steel sheet M, may be referred to as the downstream side, and the left side of the paper, which is the opposite direction, may be referred to as the upstream side. The strip steel sheet M sent downstream from the strip steel sheet supplying section 210 is a steel sheet having the above-mentioned chemical composition, and both sides (both the upper and lower sides) are coated with the above-mentioned insulating coating. The above-mentioned hardening accelerator is added to this insulating coating in advance. Therefore, in the strip steel sheet supplying section 210, the hardening accelerator is present uniformly along the upper and lower sides of the strip steel sheet M in a state that it has been dried in advance and is enclosed in the insulating coating.

[0068] The drive unit is disposed at position D between the strip steel sheet supply unit 210 and the press working oil application unit 230. The drive unit intermittently sends out the strip steel sheet M from the strip steel sheet supply unit 210 toward the press working oil application unit 230 to the right of the drawing. The hardening accelerator continues to be present uniformly along each surface on the upper and lower surfaces of the strip steel sheet M sent out from the strip steel sheet supply unit 210, in a state in which the hardening accelerator has been dried in advance and is enclosed in an insulating coating.

[0069] The press working oil application section 230 includes an application roller 231 and an oil pan 232 . The oil pan 232 is disposed below the strip steel sheet M and directly below the application roller 231. The application roller 231 has an upper roller 231a and a lower roller 231b. The upper roller 231a is disposed directly above the strip steel sheet M, and by moving up and down, can be switched between a state in contact with and a state separated from the upper surface of the strip steel sheet M. The upper roller 231a can supply press processing oil to the upper surface of the strip steel sheet M by rolling while in contact with the upper surface of the steel sheet M with press processing oil supplied from a press processing oil supply unit (not shown) permeating its outer circumferential surface. The lower roller 231b is disposed directly below the strip steel sheet M, and can be switched between a state in contact with and a state separated from the lower surface of the strip steel sheet M by moving up and down. The lower roller 231b can supply press processing oil to the lower surface of the strip steel sheet M by rolling while being in contact with the lower surface of the steel sheet M in a state in which the press processing oil supplied from the press processing oil supply unit has permeated its outer circumferential surface. The oil pan 232 receives and collects excess press oil dripping from the upper roller 231a and the lower roller 231b, and returns it to the press oil supply section.

[0070] According to the press processing oil application section 230, by supplying press processing oil from the press processing oil supply section while the upper roller 231a is in contact with the upper surface of the strip steel plate M, a layer of press processing oil can be formed over the entire surface of the insulating coating on the upper surface of the strip steel plate M, while the strip steel plate M can be continuously or intermittently sent downstream. Similarly, by supplying press processing oil from the press processing oil supply section while the lower roller 231b is in contact with the underside of the strip steel plate M, a layer of press processing oil can be formed over the entire surface of the insulating coating on the underside of the strip steel plate M, while the strip steel plate M is sent downstream continuously or intermittently.

[0071] Alternatively, by sandwiching the strip steel plate M between the upper roller 231a and the lower roller 231b, a layer of press processing oil can be formed over the entire surface of both the insulating coating on the upper surface of the strip steel plate M and the insulating coating on the lower surface of the strip steel plate M, while the strip steel plate M is sent downstream continuously or intermittently. In this way, by moving the positions of the upper roller 231a and the lower roller 231b up and down as needed, the press processing oil can be applied in three ways: only to the upper surface of the strip steel plate M, only to the lower surface of the strip steel plate M, or to both the upper and lower surfaces of the strip steel plate M.

[0072] Here, in any of the above cases, the hardening accelerator on the upper and lower surfaces of the strip steel sheet M is sealed in a dry state in the insulating coating before the press processing oil is applied, so that the concentration is prevented from being diluted by the application of the press processing oil. Therefore, the concentration of the hardening accelerator on the upper surface of the strip steel sheet M after the press processing oil is applied is maintained unchanged from the time of the hoop material M. Similarly, the concentration of the hardening accelerator on the lower surface of the strip steel sheet M after the press processing oil is applied is also maintained unchanged from the time of the hoop material M. Therefore, the strip steel sheet M after passing through the press processing oil application section 230 is sent to the press processing section 240 while maintaining the concentration of the hardening accelerator on its upper and lower surfaces.

[0073] The press processing section 240 includes a first stage punching section 241 , a second stage punching section 242 , and a third stage punching section 243 . The first-stage punching section 241 is disposed downstream of the press oil application section 230 and has a male die 241a and a female die 241b. The male die 241a and the female die 241b are disposed coaxially along the vertical direction, and the strip steel sheet M is inserted between them. Thus, the male die 241a faces the upper surface of the strip steel sheet M, and the female die 241b faces the lower surface of the strip steel sheet M. Then, in a state where the delivery of the strip steel sheet M is temporarily stopped, the male die 241a is moved downward by a hydraulic mechanism (not shown) to reach the female die 241b, thereby performing the first punching process required to form the electromagnetic steel sheet 40 of the strip steel sheet M. At this time, since the press oil is applied to the strip steel sheet M in advance, it can be punched without causing seizure or the like. After this punching process, the male die 241a is then moved upward and pulled out from the female die 241b, and the strip steel sheet M is again sent out toward the downstream side.

[0074] The second-stage punching section 242 is disposed downstream of the first-stage punching section 241 and has a male die 242a and a female die 242b. The male die 242a and the female die 242b are disposed coaxially along the vertical direction, and the strip steel sheet M after the first punching process is inserted between them. Thus, the male die 242a faces the upper surface of the strip steel sheet M, and the female die 242b faces the lower surface of the strip steel sheet M. Then, in a state where the delivery of the strip steel sheet M is again temporarily stopped, the male die 242a is moved downward by a hydraulic mechanism (not shown) to reach the female die 242b, thereby performing the second punching process required to form the electromagnetic steel sheet 40 of the strip steel sheet M. At this time, too, press processing oil is applied in advance to the upper and lower surfaces of the strip steel sheet M, so that the strip steel sheet M can be punched without causing seizure or the like. After this punching process, the male die 242a is then moved upward and pulled out from the female die 242b, and the strip steel sheet M is again sent out toward the downstream side.

[0075] The third-stage punching section 243 is disposed downstream of the second-stage punching section 242 and has a male die 243a and a female die 243b. The male die 243a and the female die 243b are disposed coaxially along the vertical direction, and the strip steel sheet M after the second punching process is inserted between them. Thus, the male die 243a faces the upper surface of the strip steel sheet M, and the female die 243b faces the lower surface of the strip steel sheet M. Then, in a state where the delivery of the strip steel sheet M is again temporarily stopped, the male die 243a is moved downward by a hydraulic mechanism (not shown) to reach the female die 243b, thereby performing the third punching process required to form the electromagnetic steel sheet 40 of the strip steel sheet M. At this time, too, press processing oil is applied in advance to the upper and lower surfaces of the strip steel sheet M, so that the strip steel sheet M can be punched without causing seizure or the like. After this punching process, the male die 243a is then moved upward and pulled out from the female die 243b, and the strip steel sheet M is again sent out toward the downstream side. After passing through the press working section 240 in this manner, the steel strip M still has high concentrations of hardening accelerator present on its upper and lower surfaces, and is sent as is to the adhesive application section 250.

[0076] The adhesive applying section 250 is incorporated in the lamination bonding section 260 located downstream of the press processing section 240. The adhesive applying section 250 includes an air compressor 251, a syringe 252, and a nozzle 253. The syringe 252 is a container for storing an adhesive, and is connected via a pipe between the air compressor 251 and the nozzle 253. The adhesive may be the same as that described in the first embodiment. The nozzle 253 is disposed above the strip steel sheet M. Therefore, the discharge port of the nozzle 253 faces the upper surface of the strip steel sheet M.

[0077] The adhesive is applied onto the surface of the press oil that covers the insulating coating on the upper surface of the strip steel sheet M. Although the press oil is liquid, the insulating coating itself is solid, so that the press oil is prevented from mixing with the hardening accelerator added to the insulating coating. Therefore, the hardening accelerator and the adhesive are kept separated from each other on the upper surface of the strip steel sheet M. As a result, the strip steel sheet M after passing through the adhesive application section 250 still has the hardening accelerator present on its upper and lower surfaces at a high concentration.

[0078] The lamination bonding section 260 is disposed downstream of the press processing section 240 and at the same position as the adhesive application section 250. The lamination bonding section 260 includes a male outer periphery punching die 261, a female outer periphery punching die 262, a spring 263, and a heater 264. The outer periphery punching male die 261 is a cylindrical die having a circular bottom surface, and the lower end of the spring 263 is connected to the upper end thereof. The outer periphery punching male die 261 is supported by the spring 263 and is movable up and down together with the spring 263. The outer periphery punching male die 261 has an outer diameter dimension that is approximately the same as that of the stator adhesive laminated core 21. The nozzle 253 is built in the outer periphery punching male die 261. The discharge port of the nozzle 253 is formed on the bottom surface of the outer periphery punching male die 261.

[0079] The outer periphery punching female die 262 is a die having a cylindrical internal space, and has an inner diameter dimension that is approximately the same as the outer diameter dimension of the stator bonded laminated core 21 . The heater 264 is integrally built into the outer periphery punching female die 262. The heater 264 heats the periphery of each of the electromagnetic steel sheets (steel sheet components) 40 stacked in the outer periphery punching female die 262. When a heat-curing type adhesive is used as the adhesive, the adhesive cures when it receives heat from the heater 264. On the other hand, when a room temperature curing type adhesive is used as the adhesive, the adhesive cures at room temperature without the need for heating.

[0080] According to the laminated adhesive section 260, while the feeding of the strip-shaped steel sheet M is temporarily stopped, the outer periphery punching male die 261 is lowered to sandwich the strip-shaped steel sheet M between it and the outer periphery punching female die 262, and the outer periphery punching male die 261 is further pushed into the outer periphery punching female die 262, thereby obtaining an electromagnetic steel sheet 40 whose periphery has been punched out from the strip-shaped steel sheet M. Furthermore, during this outer periphery punching, the air compressor 251 is started to pump an appropriate amount of air into the syringe 252, and the adhesive in the syringe 252 is sent to the nozzle 253. As a result, an appropriate amount of adhesive is discharged from the discharge port formed in the bottom surface of the outer periphery punching male die 261, and applied to the upper surface of the strip-shaped steel sheet M. The adhesive applied here is used to bond other electromagnetic steel sheets 40 that will be subsequently outer periphery punched and stacked.

[0081] The electromagnetic steel sheet 40 which has been punched out this time is stacked on the upper surface of the other electromagnetic steel sheet 40 which has been punched out previously and which has been stacked and adhered within the female outer periphery punching die 262 . Then, a pressure force from the outer periphery punching male die 261 and heat from the heater 264 are applied to each of the stacked electromagnetic steel sheets 40. At this time, the pressure force applied to the electromagnetic steel sheets 40 from the outer periphery punching male die 261 is always kept constant by the biasing force of the spring 263.

[0082] The pressure applied at this time causes the adhesive on the upper surface of the other electromagnetic steel sheet 40 punched out previously to mix with at least one of the hardening accelerator in the insulating coating on the lower surface of the electromagnetic steel sheet 40 whose outer periphery has been punched out this time and the hardening accelerator in the insulating coating on the upper surface of the other electromagnetic steel sheet 40 punched out previously, and instantly harden. As a result, the currently punched electromagnetic steel sheet 40 is adhered and fixed to the upper surface of the previously punched other electromagnetic steel sheet 40. By repeating these steps of outer periphery punching, pressurizing, and heating a number of times corresponding to the number of stacked electromagnetic steel sheets 40, an adhesive laminated core 21 for a stator is formed in the outer periphery punching female die 262.

[0083] 6, the female die 241b, the female die 242b, the female die 243b, the outer periphery punching female die 262, and the heater 264 are fixed on a common fixed base 271. Therefore, the relative positions of the female die 241b, the female die 242b, the female die 243b, the outer periphery punching female die 262, and the heater 264 are fixed in the horizontal and vertical directions. Similarly, the male die 241a, the male die 242a, the male die 243a, the nozzle 253, and the outer periphery punching male die 261 are also fixed to the lower surface of a common movable base 272. Therefore, the relative positions of these male die 241a, the male die 242a, the nozzle 253, and the outer periphery punching male die 261 are also fixed in the horizontal and vertical directions.

[0084] The drive unit sends out the strip steel plate M downstream and, when it is temporarily stopped, lowers the movable base 272, thereby simultaneously performing the following: outer periphery punching, stacking and bonding of the electromagnetic steel plate 40 and application of adhesive for the next process; the third punching process at the position on the strip steel plate M where the next outer periphery punching will be performed; the second punching process at the position on the strip steel plate M where the next third punching process will be performed; and the first punching process at the position on the strip steel plate M where the next second punching process will be performed. Next, the movable base 272 is raised and retracted above the strip steel sheet M, and then the drive unit sends out the strip steel sheet M a predetermined distance downstream again and pauses again. In this state, the movable base 272 is lowered again and processing is continued at each position. In this way, the process of moving the movable base 272 up and down during pauses while intermittently sending the strip steel sheet M by the drive unit is repeated, thereby manufacturing the stator adhesive laminated core 21.

[0085] A method for manufacturing a bonded laminated core using the bonded laminated core manufacturing apparatus 200 having the above-described configuration will be described below with reference to Fig. 7. In this embodiment, an example is shown in which an insulating coating containing a hardening accelerator is formed on the top and bottom surfaces of a strip-shaped steel plate M, press processing oil is applied to the top and bottom surfaces of the strip-shaped steel plate M, and an adhesive is applied only to the top surface of the strip-shaped steel plate M. As shown in FIG. 7, the adhesive laminated core manufacturing method of this embodiment includes a steel plate feeding process S1B, a processing oil application process S2B, a first punching process S3B, a second punching process S4B, a third punching process S5B, a fourth punching and stacking process S6B, a laminate number confirmation process S7B, and a removal process S8B.

[0086] The hardening accelerator is added to both the insulating coating i1 covering the upper surface of the strip steel sheet M and the insulating coating i2 covering the lower surface of the strip steel sheet M. For ease of explanation, the reference characters i1 and i2 are used to distinguish the insulating coatings on the upper and lower surfaces of the strip steel sheet M, but these insulating coatings i1 and i2 have the same composition and thickness. In the subsequent processing oil application process S2B, the strip steel sheet M is sandwiched between the upper roller 231a and the lower roller 231b from above and below, and press processing oils b1, b2 are applied to the top and bottom surfaces of the strip steel sheet M. As a result, a layer of press processing oil b1 is formed that covers the entire surface of the insulating coating i1. In addition, a layer of press processing oil b2 is formed that covers the entire surface of the insulating coating i2. At this time, the hardening accelerator is held within the solid insulating coatings i1, i2. Therefore, the hardening accelerator in the insulating coating i1 does not mix with the press processing oil b1 and its concentration does not decrease, and it maintains almost its original state. Similarly, the hardening accelerator in the insulating coating i2 does not mix with the press processing oil b2 and its concentration does not decrease, and it maintains almost its original state.

[0087] In the subsequent first punching process S3B, the first punching of the strip steel sheet M is performed by the first-stage punching section 241. At this time, since the press processing oils b1 and b2 have been applied to the strip steel sheet M in advance, defects in the press processing, such as seizure between the male die 241a and the female die 241b, do not occur. In the subsequent second punching process S4B, the second punching of the strip steel sheet M is performed by the second-stage punching section 242. At this time, too, press processing oils b1 and b2 have been applied to the strip steel sheet M in advance, so that defects in the press processing, such as seizure between the male die 242a and the female die 242b, do not occur.

[0088] In the subsequent third punching process S5B, the third punching of the strip steel sheet M is performed by the third-stage punching section 243. At this time as well, since the press processing oils b1 and b2 have been applied to the strip steel sheet M in advance, defects in the press processing such as seizure between the male die 243a and the female die 243b do not occur. By the above-mentioned first punching process S3B to third punching process S5B, the core back portion 22 and the teeth portion 23 shown in FIG. 1 are formed in the strip-shaped steel plate M, except for the outer shape portion.

[0089] In the subsequent fourth punching and lamination step S6B, the electromagnetic steel sheet 40 whose periphery has been punched out from the strip-shaped steel sheet M by the outer periphery punching male die 261 is laminated on the upper surface of the other electromagnetic steel sheet 40 whose periphery has been punched out previously. On the upper surface of the other electromagnetic steel sheet 40, an insulating coating i1 to which a hardening accelerator has been added, press processing oil b1 covering the insulating coating i1, and adhesive c previously applied on the press processing oil b1 are formed in this order. Also, on the lower surface of the electromagnetic steel sheet 40 whose periphery has been punched out this time, an insulating coating i2 to which a hardening accelerator has been added, and press processing oil b2 covering the insulating coating i2 are formed in this order.

[0090] The electromagnetic steel sheet 40 which has been punched this time is heated while being pressurized in a state in which it is stacked on the top surface of the other electromagnetic steel sheet 40 which has been punched previously. Then, the adhesive c on the top surface of the other electromagnetic steel sheet 40 which has been punched previously pushes aside the press processing oil b1 on the top surface of the other electromagnetic steel sheet 40 which has also been punched previously, and mixes with the hardening accelerator in the insulating coating i1. At the same time, the adhesive c pushes aside the press processing oil b2 on the bottom surface of the electromagnetic steel sheet 40 which has been punched this time, and mixes with the hardening accelerator in the insulating coating i2. In this way, the adhesive c instantly hardens while mixing with the hardening accelerator contained in both the insulating coatings i1 and i2. In this way, the hardening accelerator can be mixed with the adhesive c while maintaining its concentration, and therefore the hardening accelerator can be fully exerted.

[0091] Meanwhile, adhesive c is applied from a nozzle 253 to the upper surface of the electromagnetic steel sheet 40 that has been peripherally punched this time, at the same time that the electromagnetic steel sheet 40 that has been peripherally punched this time is laminated on the other electromagnetic steel sheets 40. This adhesive c is in a liquid state since it is on the upper surface of the electromagnetic steel sheet 40 and has not yet been mixed with the hardening accelerator.

[0092] By sequentially repeating the above steps, a predetermined number of electromagnetic steel sheets 40 are laminated and bonded together, and the bonded laminated core 21 for the stator is completed. That is, in the stacking number confirmation step S7B, it is determined whether or not the number of stacked electromagnetic steel sheets 40 has reached a predetermined number. As a result, if it has not reached that number (determination: NO), the flow returns to the steel sheet delivery step S1B, and the steel sheet delivery step S1B to the fourth punching and stacking step S6B are repeated again. On the other hand, if the predetermined number has been reached in the stacking number confirmation step S7B (determination: YES), the flow proceeds to the removal step S8B. In the subsequent removal step S8B, the completed bonded laminated core 21 for a stator is removed from the outer periphery punching female die 262, thereby completing all steps of the bonded laminated core manufacturing method.

[0093] The main points of the bonded laminated core manufacturing method using the bonded laminated core manufacturing apparatus 100 described above will be summarized below. In this embodiment, among the main points (1) to (4) described in the first embodiment, the main point (5) below is adopted instead of the main point (4). (5) In the method for producing an adhesive laminated core described in (3) above, the following steps are performed. Each steel sheet component 40 includes an electromagnetic steel sheet (third steel sheet component) 40 which is punched later and an electromagnetic steel sheet (fourth steel sheet component) 40 which is punched earlier, at its outer periphery. This bonded laminated core manufacturing method includes a fourth step of preparing a subsequently punched electromagnetic steel sheet (third steel sheet part) 40, which has, on its lower surface (third surface) side, an insulating coating i2 and press processing oil b2 applied on the insulating coating i2; a fifth step of preparing a previously outer periphery punched electromagnetic steel sheet (fourth steel sheet part) 40, which has, on its upper surface (fourth surface) side, an insulating coating i1, press processing oil b1 applied on the insulating coating i1, and adhesive c applied on the press processing oil b1; and a sixth step of overlapping and adhering the previously punched electromagnetic steel sheet (fourth steel sheet part) 40 and the subsequently punched electromagnetic steel sheet (third steel sheet part) 40 so that the lower surface (third surface) and the upper surface (fourth surface) face each other. According to the method for manufacturing a bonded laminated core described in (5) above, the hardening accelerator is dried and enclosed in the insulating coatings i1, i2 before the sixth step, so that it is prevented from mixing with the press processing oils b1, b2. Therefore, when the electromagnetic steel sheet (fourth steel sheet component) 40 punched first and the electromagnetic steel sheet (third steel sheet component) 40 punched later are overlapped and bonded in the sixth step, the hardening accelerator can mix with the adhesive c while maintaining a high concentration.

[0094] In the above embodiment, the case where press processing oils b1, b2 are applied to the upper and lower surfaces of the strip steel plate M has been described, but the present invention is not limited to this embodiment, and press processing oil b1 may be applied only to the upper surface of the strip steel plate M. This modified example will be described below with reference to Fig. 8. In this modified example, an insulating coating i1 to which a hardening accelerator has been added is formed on the upper surface of the strip steel plate M, an insulating coating i2 to which a hardening accelerator has been added is formed on the lower surface of the strip steel plate M, press processing oil b1 is applied to the upper surface of the strip steel plate M, press processing oil b2 is not applied to the lower surface of the strip steel plate M, and adhesive c is applied only to the upper surface of the strip steel plate M.

[0095] As shown in Figure 8, the adhesive laminated core manufacturing method of this modified example includes a steel plate feeding process S1C, a processing oil application process S2C, a first punching process S3C, a second punching process S4C, a third punching process S5C, a fourth punching and stacking process S6C, a laminate number confirmation process S7C, and a removal process S8C.

[0096] The steel plate delivery step S1C is the same as the above-mentioned steel plate delivery step S1B, and therefore a description thereof will be omitted. In the subsequent processing oil application step S2C, only press processing oil b1 is applied while the upper roller 231a is in contact with the upper surface of the strip-shaped steel sheet M. As a result, a layer of press processing oil b1 is formed that covers the entire surface of the insulating coating i1, while no press processing oil b2 is applied to the insulating coating i2. At this time, since the hardening accelerator is held within the insulating coating i1, which is a solid, its concentration does not decrease by mixing with the press processing oil b1, and it maintains almost its original state.

[0097] The subsequent first punching step S3C is the same as the above-mentioned first punching step S3B, and therefore a description thereof will be omitted. The subsequent second punching step S4C is the same as the above-mentioned second punching step S4B, so a description thereof will be omitted. The subsequent third punching step S5C is the same as the above-mentioned third punching step S5B, and therefore a description thereof will be omitted.

[0098] In the subsequent fourth punching and lamination step S6C, the electromagnetic steel sheet 40, the periphery of which has been punched out from the strip-shaped steel sheet M by the outer periphery punching male die 261, is laminated on the upper surface of the other electromagnetic steel sheet 40, the periphery of which has been punched out the previous time. On the upper surface of the other electromagnetic steel sheet 40, an insulating coating i1 to which a hardening accelerator has been added, a press processing oil b1 covering the insulating coating i1, and an adhesive c previously applied on the press processing oil b1 are formed in this order. Also, on the lower surface of the electromagnetic steel sheet 40, only an insulating coating i2 to which a hardening accelerator has been added is formed. The electromagnetic steel sheet 40, the periphery of which has been punched out this time, is laminated on the upper surface of the other electromagnetic steel sheet 40, the periphery of which has been punched out the previous time, and heated while being pressurized. Then, the adhesive c on the upper surface of the other electromagnetic steel sheet 40, the periphery of which has been punched out the previous time, pushes aside the press processing oil b1 on the upper surface of the other electromagnetic steel sheet 40, the periphery of which has also been punched out the previous time, and mixes with the hardening accelerator in the insulating coating i1. At the same time, the adhesive c mixes with the hardening accelerator in the insulating coating i2 on the underside of the electromagnetic steel sheet 40 that has been punched out this time. In this way, the adhesive c instantly hardens while mixing with the hardening accelerator contained in both insulating coatings i1 and i2. At this time, the hardening accelerator is able to mix with the adhesive c while maintaining its concentration, so it can fully exert its hardening acceleration effect.

[0099] Meanwhile, adhesive c is applied from a nozzle 253 to the upper surface of the electromagnetic steel sheet 40 that has been peripherally punched this time, at the same time that the electromagnetic steel sheet 40 that has been peripherally punched this time is laminated on the other electromagnetic steel sheets 40. This adhesive c is in a liquid state since it is on the upper surface of the electromagnetic steel sheet 40 and has not yet been mixed with the hardening accelerator.

[0100] By sequentially repeating the above steps, a predetermined number of electromagnetic steel sheets 40 are laminated and bonded together, and the bonded laminated core 21 for the stator is completed. Since the stack number confirmation step S7C is the same as the stack number confirmation step S7B, a description thereof will be omitted. Similarly, the removal step S8C is the same as the removal step S8B, and therefore the description thereof will be omitted.

[0101] The above describes the embodiments and modifications of the present invention. However, the technical scope of the present invention is not limited to the above embodiments and modifications, and various modifications can be made without departing from the spirit of the present invention. For example, the shape of the stator adhesive laminated core 21 is not limited to the shapes shown in the respective embodiments. Specifically, the outer and inner diameters, lamination thickness, number of slots, circumferential and radial dimensional ratios of the teeth portion 23, and radial dimensional ratios of the teeth portion 23 and the core back portion 22 of the stator adhesive laminated core 21 can be designed as desired according to the characteristics of the desired rotating electric machine. In the rotor 30 in each embodiment, a pair of permanent magnets 32 form one magnetic pole, but the manufacturing object of the present invention is not limited to this form. For example, one permanent magnet 32 ​​may form one magnetic pole, or three or more permanent magnets 32 may form one magnetic pole.

[0102] In each embodiment, a permanent magnet field type motor has been used as an example of the rotating motor 10, but the structure of the rotating motor 10 is not limited to this, as exemplified below, and various known structures not exemplified below can also be adopted. In each embodiment, a permanent magnet field type motor has been described as an example of the rotating electric machine 10, but the present invention is not limited to this. For example, the rotating electric machine 10 may be a reluctance type motor or an electromagnetic field type motor (wound field type motor). In each embodiment, a synchronous motor has been described as an example of an AC motor, but the present invention is not limited to this. For example, the rotating electric machine 10 may be an induction motor. In each embodiment, an AC motor has been described as an example of the rotating electric machine 10, but the present invention is not limited to this. For example, the rotating electric machine 10 may be a DC motor. In each embodiment, an electric motor has been given as an example of the rotating electric machine 10, but the present invention is not limited to this. For example, the rotating electric machine 10 may be a generator.

[0103] In addition, within the scope of the invention, the components in the above-described embodiments may be replaced with well-known components, and the above-described modified examples may be combined as appropriate. EXAMPLES

[0104] First, coating components Nos. 1 to 13 shown in Table 1 below were prepared. Then, any of the coating components Nos. 7 to 11, which are compounds having a curing-accelerating effect for anaerobic adhesives, were dried in advance, and then added to the coating components Nos. 1 to 5, which are insulating coating components, to prepare an insulating coating solution. Then, the concentration of this insulating coating solution was adjusted by adding an appropriate amount of pure water and stirring, to prepare a treatment liquid for forming an insulating coating. When formulating this treatment liquid for forming an insulating coating, the contents were as shown in Table 1. Similarly, an insulating coating solution was prepared by adding coating components Nos. 12 and 13, which are compounds that do not accelerate the hardening of anaerobic adhesives, to the insulating coating components Nos. 1 to 5. Then, the concentration of this insulating coating solution was adjusted by adding pure water appropriately and stirring, to prepare a treatment liquid for forming an insulating coating. When formulating this treatment liquid for forming an insulating coating, the contents were as shown in Table 1.

[0105] [Table 1]

[0106] On the other hand, multiple non-oriented electrical steel sheets were prepared, each containing, by average mass%, 3.1% Si, 0.6% Al, 0.1% Mn, with the remainder being Fe and impurities, with an average sheet thickness of 0.30 mm, and with average surface roughnesses Ra (center line average roughness) in the L direction and C direction of 0.28 μm each. The above-mentioned treatment liquid for forming an insulating coating was then applied to the surface of each of these non-oriented electrical steel sheets in an average amount of 1.2 g / m. 2 The non-oriented electrical steel sheet was then baked in a 500°C heating furnace for 60 seconds so that the sheet temperature reached 200°C or 350°C, forming an insulating film. A preferred amount of the treatment liquid to be applied in the insulating film forming step is 0.4 g / m2 on average. 2 ~2.0g / m 2 The sheet temperature of the non-oriented electrical steel sheet in the heating furnace may be within a range of 140° C. to 330° C. The baking time of the non-oriented electrical steel sheet in the heating furnace may be within a range of 15 seconds to 60 seconds.

[0107] The coating components Nos. 7 to 11, which are compounds having a curing-accelerating effect shown in Table 1, were adjusted in a treatment liquid so that the solid content in the coating was the specified part by mass shown in Table 1. In some cases, a dispersant such as a surfactant was also used appropriately. The same treatment was also carried out for Nos. 12 and 13, which are compounds that do not have the effect of accelerating the hardening of the anaerobic adhesive. Incidentally, when preparing the treatment liquid, it is considered that the content of the compound per 100 parts by mass of water and solvent is within the range of 0.2 parts by mass to 20 parts by mass.

[0108] Next, the initial adhesive strength, final adhesive strength, and insulating performance were examined for each of Examples 1 to 5 and Comparative Examples 1 to 4. The results are shown in Table 2 below.

[0109] [Table 2]

[0110] In Table 2, when evaluating the initial adhesive strength and the final adhesive strength, a 30 mm x 60 mm sample was first prepared. Then, punching oil was applied to the entire surface of this sample. Then, 5 μl of anaerobic adhesive was dripped onto the edge of the surface of the sample where the punching oil was applied, in an area of ​​30 mm x 10 mm, to form an adhesive surface. Then, immediately after dripping the anaerobic adhesive, another non-oriented electrical steel sheet was placed on the adhesive surface of this sample. The adhesive strength was measured after maintaining the pressure at 0.3 MPa for 20 seconds from the start of lamination and recorded as the initial adhesive strength, and the adhesive strength was measured after leaving the pieces for 24 hours from the start of lamination and recorded as the final adhesive strength.

[0111] In addition to the evaluation of the initial adhesive strength and the final adhesive strength, as shown in Table 2, the removal time when 100 sheets were stacked was also evaluated. That is, the "100-sheet laminated core removal time" shown in Table 2 was determined by first processing non-oriented electrical steel sheets having an insulating coating of the coating composition shown in Table 1 into multiple ring-shaped test pieces with an outer diameter of 60 mm and an inner diameter of 40 mm using a die. Then, after applying punching oil to each surface of these test pieces, 5 μl of anaerobic adhesive was applied to each of four places on each surface. Then, immediately after applying the anaerobic adhesive, these test pieces were stacked on top of other test pieces. This stacking was repeated at a stacking speed of 20 spm, and as a result, 100 test pieces were stacked to obtain a laminated core. The shortest time from the start of measurement when stacking was completed to the end of measurement when the laminated core obtained in this way could be removed without deviation was determined as the "100-sheet laminated core removal time".

[0112] Furthermore, in order to confirm that the insulating performance of the insulating coating is sufficiently secured in the non-oriented electrical steel sheets in the single sheet state before forming the 100-sheet laminated core, the surface insulation resistance shown in Table 2 was also measured. This measurement was performed according to the method of JIS C 2550. And, when the value of the surface insulation resistance was 10 Ω-cm 2 It was determined that if the range was 1 / sheet or more, sufficient insulation performance was ensured.

[0113] In Table 2, the initial adhesive strength was evaluated as Good (pass) when it was 1 MPa or more, Bad (fail) when it was less than 0.1 MPa, and Not Good when it was in between. The final adhesive strength was measured after applying a pressure of 0.5 MPa to the bonded test piece and holding it for 24 hours. As a result of the measurement, an adhesive strength of 5 MPa or more was evaluated as Good (pass), and an adhesive strength of less than 5 MPa was evaluated as Bad (fail). On the other hand, for the "time to remove 100 laminated cores," a time of 20 seconds or less was rated as Good (passed), a time of 60 seconds or more was rated as Bad (failed), and any time in between was rated as Not Good.

[0114] Based on the above evaluation results, a score of Good for all evaluation items was given an overall rating of Good, a score that included at least one Not Good was given an overall rating of Not Good, and a score that included at least one Bad was given an overall rating of Bad. As shown in Table 2, Examples 1 to 5 all received an overall rating of Good, whereas Comparative Examples 1 to 3 received an overall rating of Bad and Comparative Example 4 received an overall rating of Not Good. In addition, in all of Examples 1 to 5 that received a "Good" rating in the overall evaluation, the interlayer resistance was 10 Ω-cm 2 It was also confirmed that sufficient insulation performance was obtained because the test satisfied the requirement of 1 / sheet or more. From the above, it was confirmed that by using an electrical steel sheet having an insulating coating containing a curing accelerator formed on one or both sides, it is possible to obtain higher productivity while ensuring sufficient adhesive strength when manufacturing an adhesive laminated core. In addition, it was also confirmed that a sufficiently high insulating performance is ensured even if a curing accelerator is added to the insulating coating.

[0115] Normally, adding a curing accelerator would be considered to affect the insulating performance of the insulating coating, and such a composition would be avoided. Similarly, normally, one would not think of using a curing accelerator to improve the adhesive effect when a so-called "dirt layer" such as press processing oil remains on the insulating coating. Since a curing accelerator is an organic resin, if one wants to include it in something, the general idea is to mix it into the organic resin. However, the present inventors adopted a structure in which the curing accelerator, which is an organic resin, is dried in advance and then mixed with the curing accelerator, which is an inorganic substance. As shown in the above examples, the inventors discovered that when this structure is used, a high adhesive effect can be obtained while ensuring sufficient insulation performance, and thus arrived at the present invention. [Industrial Applicability]

[0116] According to the above-mentioned aspects of the present invention, it is possible to provide an electromagnetic steel sheet and a method for manufacturing a bonded laminated core, which can ensure sufficient adhesive strength and achieve higher productivity when manufacturing a bonded laminated core, and thus has great industrial applicability. [Explanation of symbols]

[0117] 21 Adhesive laminated core for stator (adhesive laminated core, stator for rotating electric machine) 40 Electromagnetic steel plate, steel plate part, first steel plate part, second steel plate part, third steel plate part, fourth steel plate part b1, b2 Press processing oil C. Adhesive i1, i2 Insulation coating M Steel strip, electromagnetic steel sheet

Claims

1. Chemical composition, in mass percent, Si: 2.5% to 3.9% Al: 0.001% to 3.0% Mn: 0.05% to 5.0% Remainder: Fe and impurities Contains An insulating coating containing a hardening accelerator is formed on one or both sides. The curing accelerator is sealed in the insulating coating in a dry state.

1. An electrical steel sheet comprising:

2. 2. The electrical steel sheet according to claim 1, wherein the hardening accelerator comprises an active ingredient that promotes anaerobic hardening, selected from titanium, chromium, manganese, iron, cobalt, nickel, copper, zinc, silver, vanadium, molybdenum, ruthenium, and combinations thereof.

3. A method for manufacturing an adhesive laminated core, comprising the steps of: pressing a strip of steel plate having press working oil applied to one or both sides thereof; applying an adhesive to one side of the strip of steel plate to obtain a plurality of steel plate parts; and laminating and bonding the steel plate parts together, the method comprising the steps of: The electrical steel sheet according to claim 1 or 2 is used as the strip steel sheet. A method for manufacturing a bonded laminated core.

4. The steel plate components include a first steel plate component and a second steel plate component, A first step of preparing the first steel sheet component having the insulating coating on a first surface side; a second step of preparing the second steel plate component having, on a second surface side, the insulating coating, the press working oil applied on the insulating coating, and the adhesive applied on the press working oil; A third step of overlapping and adhering the first steel plate part and the second steel plate part so that the first surface and the second surface face each other; 4. The method of claim 3, further comprising the steps of:

5. The steel plate components include a third steel plate component and a fourth steel plate component, a fourth step of preparing the third steel plate component having the insulating coating and the press working oil applied on the insulating coating on a third surface side; a fifth step of preparing the fourth steel plate component having, on a fourth surface side, the insulating coating, the press working oil applied on the insulating coating, and the adhesive applied on the press working oil; A sixth step of overlapping and adhering the third steel plate part and the fourth steel plate part so that the third surface and the fourth surface face each other; 4. The method of claim 3, further comprising the steps of:

6. 4. The method for producing a bonded laminated core according to claim 3, wherein the bonded laminated core is a stator for a rotating electrical machine.

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