Method and apparatus for manufacturing a laminated core from a metal sheet

Abstract

The present invention relates to a method and an apparatus for manufacturing a laminated core (2) from a thin metal sheet (1), in which an adhesive medium is applied as at least one adhesive point (22) onto the upper surface of a thin metal sheet insulator (21) of a thin metal sheet strip (5) guided horizontally with respect to the direction of gravity, by means of an application unit (35) via an application head (32). The transfer of the adhesive medium as at least one adhesive point (22) onto the surface of the thin metal sheet insulator (21) of the thin metal sheet strip (5) or of the thin metal sheet (1) cut from the thin metal sheet strip is effected without movable components within the application head (32), and the application head (32) is moved perpendicular to the surface of the thin metal sheet strip (5) for the transfer of the adhesive medium in the form of at least one adhesive point (22), whereby advantages with respect to structure and function are obtained.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a laminated core from a thin metal sheet, in which an adhesive medium is applied as at least one adhesive point onto the upper surface of a thin metal sheet insulator of a thin metal sheet strip guided horizontally with respect to the gravitational direction, via an application head by an application unit. Furthermore, the present invention relates to an apparatus provided with an application unit for manufacturing a laminated core from a thin metal sheet, the application unit having an application head, at least one dispenser for the adhesive medium provided with at least one supply for the adhesive medium, and a frame for holding the dispenser and at least one application head.

Background Art

[0002] A method and an apparatus of such a type are described in European Patent No. 1833145.

[0003] The production of laminated cores made of multiple metal sheets for electromechanical devices (motors, generators) is carried out economically in a punching process. In this case, according to the laminated core to be produced, magnetic properties, insulation layers, and coils existing on the pay-off machine with widths already adjusted are supplied to the punching press. Downstream of the pay-off machine, a straightening unit is often located. The feeding system existing in the punching press conveys the metal sheet strip of the coil step by step into the punching tool existing within the punching press. The step width is also adjusted according to the laminated core to be produced. Inside the punching press, the punching tool generates the inner contour of the metal sheet step by step. After the completion of the inner contour, the metal sheet is punched from the metal sheet strip of the coil by a piercing punch and delivered to a so-called piercing die. To manufacture the laminated core, the metal sheets are joined in the piercing die to form one laminated core. With each working stroke of the punching press, the laminated core becomes larger. Below the piercing die, a stack brake is located, and this stack brake serves to apply the reaction force necessary to join the metal sheets to form the laminated core. With each working stroke of the punching press, the laminated core located within the piercing die and the stack brake moves downward by the thickness of the metal sheet. Stack separation is carried out by stopping the device for manufacturing stack bonding once, so that two adjacent metal sheets cannot be joined once. Inside the stack brake, a plurality of laminated cores can be located. After the laminated core is conveyed through the stack brake, usually, the laminated core located at the lower end of the stack brake is delivered to the conveying system, and the conveying system conveys the completed laminated core out of the punching press.

[0004] To form a laminated core by joining metal sheets within the punching process, various methods are used, namely punching lamination, pasting lamination, and adhesive lamination.

[0005] By punching lamination, dot-like connections between adjacent thin metal sheets are produced. In punching lamination, embossing protrusions are processed on each thin metal sheet. In a punching die, the embossing protrusions of adjacent thin metal sheets are pushed into each other. The frictional force of the mutually pushed-in embossing protrusions generates a holding force between adjacent thin metal sheets, thereby forming a laminated core in a stepwise manner. Laminated body separation is performed by punching a notch, and this notch is dimensioned and positioned so that the embossing protrusion cannot be processed at least once at the location of this notch. Therefore, in this punching die, two adjacent thin metal sheets cannot be joined at least once. Punching lamination is a method used worldwide for manufacturing laminated cores. However, in this case, the embossing protrusions processed cause electrical contact between adjacent thin metal sheets, thereby causing so-called iron losses and ultimately reducing the efficiency of the electromechanical device.

[0006] Adhesive lamination is a special form of manufacturing a laminated core from thin metal sheets, and the insulating layer of the thin metal strip of the coil has additional adhesive properties. This adhesive property is selected to be activated only under the action of temperature and / or only by an activator. This adhesive property of the insulating layer provides a full-surface connection between the thin metal sheets. Such a method is described in European Patent Application Publication No. 2450189, and this method can be incorporated into the punching process. The equipment required to incorporate the adhesive lamination method into the punching process is complex, thus costly and time-consuming to maintain.

[0007] In the case of an adhesive lamination as described in the above-mentioned European Patent No. 1833145, the efficiency drawbacks of a punched lamination and the high energy costs of an applied lamination are eliminated. In this case, the adhesive points are applied in the form of droplets onto the insulating layer of the metal sheet strip. In the piercing die of the punching tool, adjacent metal sheets are pressed against each other. In this case, the adhesive points are distributed onto the surfaces of the adjacent metal sheets. When passing through the laminate brake located below the outflow die, a period occurs during which the adhesive medium is cross-linked to the metal sheet to such an extent that at least a predetermined strength of the laminated core occurs when leaving the laminate brake. Such a form of adhesive lamination produces a planar bond between the metal sheets in the area of the application points without adversely affecting the magnetic properties of the metal sheet strip and thus of the final product. In such an adhesive lamination method incorporated into the punching process, the adhesive points are applied to the upper and / or lower surfaces of the strip surface by a piezoelectric metering system. The application unit consists of at least one application head operating in a non-contact manner, is connected to a controlled valve, and has at least one actuator provided with a piezoelectric crystal. Thus, the lower surface side of the adhesive can also be applied by such a member actively moving and located within the application unit. When the equipment control unit transmits an interruption signal to the piezoelectric metering system to stop the application of the adhesive points, the laminate separation takes place. Notches are provided in the tools, dies, and guides to protect the adhesive points applied onto the metal sheet strip. Thus, the devices required to incorporate the adhesive lamination method into the punching process are also complex, laborious to maintain, and thus costly.

[0008] In the adhesive lamination method disclosed in the German Utility Model No. 20318993, the cutting punch preferably has a flat end face, which may be interrupted and thus may include a notch. It has been shown that the adhesive points are applied to the metal sheet strip from below. This adhesive lamination method is based on the strip material coming into contact with the surface of the metering unit, thereby causing the ball to move and thus releasing the adhesive flow.

[0009] European Patent Application Publication No. 3217520, as well as Korean Registered Patent Publication No. 10-1566486, also disclose an adhesive lamination method in which an application unit for the adhesive medium is incorporated into the lower part of the punching tool. The adhesive medium is provided to an outflow nozzle at a predetermined flow rate under pressure and thereby applied onto the lower surface of the metal sheet strip. An activator for the adhesive medium can be applied together with the strip lubricant. The adhesive droplet residues that have not been delivered can be discharged in a passage passing through the lower part of the tool.

[0010] In Japanese Patent Application Laid-Open No. 2001-321850, an adhesive lamination method for applying adhesive droplets to a metal sheet strip within a punching tool is presented. Before applying the adhesive droplets onto the metal sheet strip, the metal sheet strip is cleaned. The curing of the adhesive medium can be promoted by heat supply in the laminate brake.

[0011] In the adhesive lamination method described in German Patent Application Publication No. 3535573, the control of laminate separation is performed based on the measurement of the thickness of the supplied metal sheet strip, and within the punching process, individual thin sheets are joined by the adhesive medium applied via a metering device to form a laminated core. The supply of the adhesive is carried out by a hose leading from the metering device to the punching punch, by a hose passing through the punching punch, or without a hose. A heating device can be provided in the passage below the punched part discharging device and the laminate brake to promote adhesive curing. When a two-component adhesive is used, metering is directly performed by the hose passage of the pressing plate and the cutting punch insert. In this case, the activator is phase-shifted at a predetermined adhesion point and adhered to the lower surface of the punched part by a commercially available metering needle. When a one-component adhesive is used, the adhesive is adhered to the lower surface of the punched part through the metering needle by a metering needle device.

[0012] All adhesive lamination methods known in the market for manufacturing laminated cores from metal sheets use a time-consuming dispenser system for the adhesive medium and a metering system or application system, and / or tend to contaminate the area of the application head.

Summary of the Invention

Problems to be Solved by the Invention

[0013] The underlying problem of the present invention is to provide a method or apparatus in the form described at the beginning that provides a coating method that is as simple and maintenance-free as possible, and thus inexpensive, for applying adhesive points to the surface of a thin metal strip or thin metal sheet.

Means for Solving the Problems

[0014] According to the present invention, this problem is solved in the manufacture of a laminated core by a method having the features of claim 1 and in an apparatus having the features of claim 14.

[0015] In this method, the delivery of an adhesive medium as at least one adhesive point onto the surface of a thin metal strip or a thin metal sheet cut from a thin metal strip is carried out without a movable component within the application head, and it is specified that the application head is moved perpendicular to the surface of the thin metal strip for the delivery of the adhesive medium in the form of at least one adhesive point.

[0016] In the apparatus, it is specified that the dispenser is manufactured by an additive method, in particular by a 3D printing method.

[0017] By means of such measures, the bonding method is advantageously incorporated into the manufacturing process of the laminated core, and the bonding method is carried out during the punching process or after the punching process. In a detailed investigation by the inventors, it has been found that by means of such measures, the supply of the adhesive for applying the adhesive points can be controlled or adjusted according to accurate settings without providing a movable component in the coating head and without a laborious configuration of the supply unit. The contamination of the metering system, especially of the coating head, is at least substantially avoided. By supplying the adhesive medium to the upper surface of the surface of the metal sheet insulator while moving the coating head in a direction perpendicular to the direction of gravity, that is, without the movable members and their operations existing in the coating head as in the prior art, the adhesive medium is delivered accurately in a predefinable amount under the action of gravity and by an adjustable kinetic energy, and in some cases, the influence of the cohesive force acting in this case can also be taken into account. By combining such a combination of physical forces utilized with a simple structure of the coating unit, a coating system for the adhesive medium that operates precisely, reliably, and in this case economically is maintained during the lamination of the metal sheets. It should be noted that the expression "~ point" should not be understood strictly mathematically here, but in this case, it should be understood as having a geometric extension based on its volume in accordance with the actual situation.

[0018] The device for manufacturing the laminated core can be easily and optimally adjusted in accordance with the application of the adhesive medium with the above parameters by means of the configuration of a dispenser (similarly without a movable member arranged inside), by an additional method, especially by a 3D printing method, and with a high precision of an arbitrary passage guide having an arbitrary passage cross-section and a connection geometry for the coating head.

[0019] Advantageous configurations of the present invention are described in the dependent claims.

[0020] When the adhesive medium application is incorporated into the punching process, it has been specified that, advantageously, the coating head is moved synchronously with respect to the working stroke of the punching press.

[0021] In particular, when the application of the adhesive medium is carried out downstream of the punching process, an advantageous configuration consists in moving the application head without synchronizing it with the working stroke of the punching press.

[0022] Advantageously, the volume of the adhesive medium required at the application head is provided by the pressure height and the pulse duration, depending on the viscosity of the adhesive medium and the kinetic energy of the application head (also in accordance with the configuration of the application head).

[0023] In a further advantageous configuration of the method, in order to accurately deliver the adhesive medium onto the metal sheet insulator or the metal sheet, the delivery of the adhesive medium as an adhesive point onto the metal sheet strip or the metal sheet insulator of the metal sheet is assisted, or not, by the dispenser of the application unit and the kinetic energy of the application head, and by the gravity of the adhesive medium, using or not using the adhesive force of the adhesive point in the metal sheet strip.

[0024] In order to incorporate this method into the manufacturing process of the laminated core and make it function precisely, during the delivery of the adhesive medium, the application head does not contact the surface of the metal sheet strip or the metal sheet insulator of the metal sheet. In this case, the distance between the application head and the metal sheet strip or the metal sheet is at most 5 mm, preferably at most 1 mm, which further contributes to the measure.

[0025] In order to form the best possible adhesive surface or adhesive bond between the metal sheets, and to apply the adhesive medium accurately adapted, it is further specified that the surface of the metal sheet insulator of the metal sheet is only partially wetted during the application of the adhesive point.

[0026] A further advantageous measure for forming the adhesive surface consists in monitoring the application of the adhesive point onto the metal sheet insulator of the metal sheet strip or the metal sheet by means of a sensor with respect to the presence and size of the partial wetting.

[0027] To accurately adapt the bonding surface to the metal sheet, it further contributes to adjusting the volume of each bonding point.

[0028] The high quality of the configuration of the bonding surface during the manufacturing process and during the bonded joint is also ensured by autonomously adjusting the volume of each bonding point by means of a control circuit (Regelkreis).

[0029] The uniform application of the bonding medium to optimize the bonding surface is further facilitated by applying a plurality of bonding points onto the surface of the metal sheet strip or the metal sheet via at least one dispenser having at least one supply section for the bonding medium and via at least one application head connected to the at least one dispenser. One or more application heads can be attached to the dispenser. For example, each application head can apply only one bonding point per movement step. In an alternative configuration, a plurality of bonding points can also be applied by one application head.

[0030] The integration of the adhesive application into the punching process is achieved by the application unit for the application of the bonding points being located within the punching process.

[0031] The advantageous application of the bonding medium is further carried out by the application unit for the application of the bonding medium being located outside the punching process, in particular downstream of the punching process.

[0032] Another advantageous configuration of this method is that the dispenser and the application head for the application of the bonding medium are located inside the punching punch of the punching tool.

[0033] The device is preferably configured by at least one dispenser for the bonding medium being made of a metal material or at least one dispenser for the bonding medium being manufactured from a non-metallic material, in particular from a plastic, preferably from a thermosetting plastic.

[0034] A particularly advantageous configuration of the device for structure and function lies in the fact that the application head does not include movable components, particularly driven components. Such a configuration results in a structure of an application system that can operate almost without problems and is well adapted to the required functions in relation to additional methods for manufacturing the dispenser.

[0035] For a uniform, high-quality, precise functional form of adhesive application and reliable monitoring, sensors, particularly optical sensors, are provided to monitor the presence and size of partial wetting of the metal sheet strip or metal sheet with adhesive points. The monitoring by the sensors further contributes to being carried out during or after the application of the adhesive medium. In this case, the expression "sensor" should be understood in a broad sense, so the optical sensor may be, for example, a camera system for image processing for comparing target values and actual values.

[0036] Another configuration advantageous for the function and structure of the device is that the volume of the adhesive point is adjustable, and in particular, it is autonomously adjustable by a control circuit equipped with sensors for monitoring partial wetting of the metal sheet strip or metal sheet with adhesive points.

[0037] The high quality of the application and distribution of the adhesive medium is promoted by the fact that the distance between the application heads is particularly at most 5 mm, preferably at most 3 mm, from each other. For some products, larger distances may also be considered.

[0038] A laminated core that meets high requirements for structure and function can be obtained by manufacturing the laminated core by the method according to any one of claims 1 to 13.

[0039] The present invention will be described in detail below with reference to the drawings and examples.

Brief Description of the Drawings

[0040]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

[0041] Figure 1 schematically shows an apparatus for manufacturing a large number of laminated cores 2 from a thin metal sheet 1 within a punching process 3. A laminated core 2 composed of a large number of thin metal sheets 1 is illustrated in Figure 2.

[0042] To manufacture the laminated core 2, a thin metal sheet strip 5 is fed from a coil 4 by a pay - out machine 6, optionally supplied to a straightening unit 7, and fed step - by - step via a feed system 8 to the working chamber of a punching press 9 and a punching tool 10. As partially shown in Figure 3, the thin metal sheet strip 5 consists of a (magnetic) core material 20 with insulating layers 21 applied on both sides.

[0043] Within the punching tool 10, first, positioning holes for ensuring an exact step width for feeding the thin metal sheet strip 5 step - by - step within the punching tool 10 are punched in the thin metal sheet strip 5. Then, within the punching tool 10, the inner contour of the thin metal sheet 1 is punched step - by - step in an area 40 for manufacturing the inner contour in the thin metal sheet strip 5. When all the inner contours of the thin metal sheet 1 to be punched in advance have been punched in the thin metal sheet strip 5, the thin metal sheet 1 is punched out from the thin metal sheet strip 5 by a piercing punch 43 and delivered to a piercing die 41 provided with a laminate brake 42 located thereunder (see Figure 4).

[0044] Figure 5 shows an embodiment of the present invention, in which an application unit 35 for an adhesive medium for bonding thin metal sheets 1 laminated to each other is located in the working chamber of the punching press 9 between the feed system 8 and the punching tool 10. The thin metal sheet strip 5, whose strip width and strip thickness are adapted to the outer dimensions of the thin metal sheet 1, is fed step - by - step by the feed system 8 to the punching tool 10, where the step width is adapted to the outer diameter of the thin metal sheet 1. In this case, the thin metal sheet strip 5 also passes through the application unit 35 step - by - step. The application unit 35 is positioned in the working chamber of the punching press 9 so as to be able to apply adhesive points 22 onto the insulating layer 21 of the thin metal sheet strip 5 at the correct positions (see Figure 3).

[0045] The coating unit 35 consists of a frame 30, and a dispenser 31 is attached within this frame. A coating head 32 is also attached to the dispenser 31, and the number and position of the coating heads are selected and arranged such that, as long as the metal sheet strip is not moved by the feeding system, an adhesive point 22 at an exact position can be applied onto the metal sheet strip.

[0046] To apply the adhesive point 22 onto the metal sheet strip 5, the adhesive medium is supplied in a pulsed manner from a separate adhesive container (not shown here, usually located in the pneumatic and fluid parts of the control cabinet) spaced from the coating unit 35, through a dosing pump or a compressed air valve (which generates pressure within the adhesive container), via a supply section for the adhesive medium 34, to the dispenser 31 and the coating head 32 attached above the dispenser. The pulse cycle for supplying the adhesive medium is synchronized with the working cycle of the punching press 9. The pulse duration and pressure are adjusted such that the adhesive point 22 on the metal sheet strip 5 reaches a predetermined size. The dispenser 31 has a passage system for uniformly distributing the adhesive medium to the coating head 32. The plate of the frame 30 to which the dispenser 31 equipped with the coating head 32 is attached can move vertically up and down (with respect to the gravitational or measuring direction). In this case, the vertical movement may be performed synchronously or asynchronously with respect to the working stroke of the punching press 9.

[0047] When an adhesive medium is provided at the lower end of the coating head 32, the dispenser 31 and the coating head 32 are moved in the vertical direction in the frame 30 in the direction of the metal sheet strip 5 to such an extent that the coating head 32 does not contact the metal sheet strip 5. In this case, the distance between the coating head 32 and the metal sheet strip 5 is at most 5 mm, preferably at most 1 mm. Supported also by the kinetic energy of the movement of the dispenser 31 and the coating head 32, the gravitational force of the adhesive medium at the lower end of the coating head 32, and optionally the adhesive force of the adhesive medium acting on the metal sheet strip 5, the adhesive medium is delivered to the upper surface of the metal sheet strip 5 in the form of the adhesion points 22. When the adhesion points 22 are delivered onto the metal sheet strip 5, the dispenser 31 provided with the coating head 32 is moved vertically upward again in the frame 30, and after the punching operation in the punching tool 10 is completed, the metal sheet strip 5 is further moved by one step by the feeding system 8.

[0048] This adhesion point application is repeated until the required number of metal sheets 1 with the adhesion points 22 reaches the number required to manufacture the laminated core 2. Then, for the separation of the laminate, the application of the adhesion points 22 to the metal sheet strip 5 is interrupted once by stopping the pulse for supplying the adhesive medium 34 to the dispenser 31 and the coating head 32 once. The separation of the laminate can be promoted by not performing the vertical movement of the dispenser 31 and the coating head 32 simultaneously with the stopping of the pulse for providing the adhesive medium.

[0049] The monitoring of the effective application of the adhesion points 22, in particular the monitoring of the presence and the size or volume of the adhesion points 22 on the metal sheet strip 5, is performed by one or more sensors 33 arranged downstream of the coating unit 35. In a special configuration, the size of the adhesion points 22 is adjusted by the pulse duration and the pressure for providing the adhesive medium via the sensor 33 for monitoring the size of the adhesion points 22.

[0050] After applying the subsequent point 22 onto the metal thin plate strip 5, the metal thin plate strip 5 is conveyed stepwise through the punching tool 10, and the inner contour of the metal thin plate 1 is punched into the metal thin plate strip 5 in the area 40 for manufacturing the inner contour as shown in FIG. 4. A punching punch 43 is positioned in the punching unit of the punching tool 10. The punching punch punches out one metal thin plate 1 from the metal thin plate strip 5 in each working stroke of the punching press 9 and delivers it to the punching die 41. When the punched metal thin plate 1 contacts the metal thin plate 1 located thereunder, the adhesion point 22 is crushed between the two adjacent metal thin plates 1, and thereby, it is distributed planar on the surfaces of the two adjacent metal thin plates 1.

[0051] In each working stroke of the punching press 9, another metal thin plate 1 is pressed into the punching die 41 by the punching punch 43, and the laminate of the metal thin plates 1 located thereunder is moved downward by a distance equal to the thickness of the metal thin plate. A laminate brake 42 is positioned below the punching die 41 to generate a time for the adhesion point 22 distributed planar between the metal thin plates 1 to cure in order to form the laminated core 2. This laminate brake generates an axial holding force inside the die 41 and the laminate brake 42 in the form of friction against the laminated core 2 by a radial preloading gravity. When the completed laminated core 2 reaches the lower end of the laminate brake 42, the laminated core is delivered to the conveying system 11 by gravity or via a lift system there, and the conveying system conveys the completed laminated core 2 out from the punching press 9.

[0052] In another embodiment of the present invention shown in FIG. 6, the coating unit 35 is arranged downstream of the punching process 3. With this configuration, between the punching process 3 and the application of the adhesion point 22 onto the insulating layer 21 of the metal thin plate, another processing step such as heat treatment, which may weaken or break the adhesion bond pre-formed between the metal thin plates 1 to form the laminated core 2, can be carried out on the metal thin plate 1.

[0053] The coating unit 35 also has a frame 30, and a dispenser 31 is attached within this frame. A coating head 32 is attached to the dispenser 31 provided with a supply section for the adhesive medium 34, and the number and position of the coating heads are selected and arranged so that the adhesive points 22 at the exact positions can be coated onto the metal sheet 1.

[0054] First, the metal sheet 1 is manually or automatically inserted into the coating unit 35 at an exact position. To apply the adhesive points 22 onto the metal sheet 1, the adhesive medium is supplied in predetermined pulses through the supply section for the adhesive medium 34 in the dispenser 31 and the coating head 32 attached to the dispenser. The pulse duration and pressure are adjusted so that the adhesive points 22 on the metal sheet 1 reach a predetermined predefined size or predefined volume. The dispenser 31 has a passage system for uniformly distributing the adhesive medium to the coating head 32. The plate of the frame 30 to which the dispenser 31 with the coating head 32 is attached can move vertically up and down. The vertical movement can, in this case, be performed manually or by automatic drive. When the adhesive medium is provided at the lower end of the coating head 32, the dispenser 31 and the coating head 32 are moved manually or by automatic drive within the frame 30 in the vertical direction towards the metal sheet 1 to such an extent that the coating head 32 does not contact the metal sheet 1. In this case, the distance between the coating head 32 and the metal sheet 1 is at most 5 mm, preferably at most 1 mm. Supported by the kinetic energy of the movement of the dispenser 31 and the coating head 32, the gravitational force of the adhesive medium at the lower end of the coating head 32, and optionally the adhesive force of the adhesive medium in the metal sheet 1 that exists, the adhesive medium is delivered to the upper surface of the metal sheet 1 in the form of the adhesive points 22. When the adhesive points 22 are delivered onto the metal sheet, the dispenser 31 with the coating head 32 is moved back to the starting position vertically upwards within the frame again.

[0055] Next, the metal sheet 1 is manually or automatically removed from the application unit 35 and supplied to the stacking unit, where the metal sheets 1 are stacked and pressed against each other at precise positions. By pressing adjacent metal sheets 1 against each other, the adhesive points 22 are distributed planar between the metal sheets. During the application of pressure and time, the adhesive points or adhesive surfaces harden and the adjacent metal sheets 1 are joined to form the stacked core 2. The completed stacked core 2 is manually or automatically removed from the stacking unit.

[0056] In the third embodiment of the invention shown in FIG. 7, a dispenser 31 and an application head 32 are integrated into the punching punch 43 inside the punching tool 10. In this configuration, advantageously, a particularly short dispensing path for the adhesive medium results.

[0057] To apply the adhesive points 22 onto the metal sheet strip 5, in this embodiment too, the adhesive medium is supplied in pulses via a supply section for the adhesive medium 34 in the dispenser 31 and an application head 32 attached to the dispenser.

[0058] The pulse cycle is synchronized with the working cycle of the punching press 9. The pulse duration and pressure are adjusted so that the adhesive points 22 on the metal sheet strip 5 reach a predetermined size. The dispenser 31 has a passage system for uniformly distributing the adhesive medium to the application head 32. At the earliest, when the piercing punch 43 moves upward during the upward movement of the press plunger and reaches a distance of at least 1 mm from the surface of the previously punched metal sheet 1, the provision of the adhesive medium at the lower end of the application head 32 begins. When the piercing punch 43 moves downward by the press plunger, when the distance between the piercing punch 43 and the metal sheet strip 5 is at least 1 mm at the latest, the provision of the adhesive medium at the lower end of the application head 32 ends. When the piercing punch 43 contacts the metal sheet strip 5 during the downward movement and the piercing process of the metal sheet 1 from the metal sheet strip 5 begins, the adhesive medium is delivered from the application head 32 to the metal sheet strip in the form of the adhesive points 22. While the adhesive medium is being applied onto the metal sheet strip 5, the application head 32 does not contact the metal sheet strip 5, and at this time, the distance between the application head 32 and the metal sheet strip 5 is at most 5 mm, preferably at most 1 mm. Supported by the kinetic energy of the dispenser 31 and the application head 32 in the piercing punch 43 and the gravitational force of the adhesive medium at the lower end of the application head 32, and under the action of the adhesive force of the adhesive medium in the metal sheet strip 5 that may exist in some cases, the adhesive medium is delivered to the upper surface of the metal sheet strip 5 in the form of the adhesive points 22. When the adhesive points 22 are delivered to the metal sheet strip 5, the piercing process of the metal sheet 1 from the metal sheet strip ends, and when the piercing punch 43 is surely separated from the metal sheet strip 5 during the upward movement, the metal sheet strip 5 is further moved by one step by the feed system 8.

[0059] This adhesive dot application is repeated until the required number of metal thin plates 1 with adhesive dots 22 is reached for manufacturing the laminated core 2. Then, for laminate separation, the application of the adhesive dots 22 to the metal thin plate strip 5 is interrupted once by stopping the pulse for supplying the adhesive medium 34 to the dispenser 31 and the coating head 32 once. When the dispenser 31 and the coating head 32 are inside the punching punch 43 and are lifted by at least 0.5 mm once under automatic drive simultaneously with the stop of the pulse for providing the adhesive medium, laminate separation can be promoted.

[0060] In each working stroke of the punching press 9, one metal thin plate is punched out from the metal thin plate strip 5 and delivered to the punching die. When the punched metal thin plate 1 contacts the metal thin plate 1 located below it, the adhesive dots 22 between the adjacent two metal thin plates 1 are crushed, and thereby are distributed planar on the surfaces of the adjacent two metal thin plates 1.

[0061] In each working stroke of the punching press 9, another metal thin plate 1 is pressed into the punching die 41 by the punching punch 43, and the laminate of the metal thin plates 1 located below it is moved downward by the value of the thickness of the metal thin plate. In order to generate the time for the adhesive dots 22 to cure between the metal thin plates 1 for forming the laminated core 2, a laminate brake 42 is located below the punching die 41, and this laminate brake generates an axial holding force inside the die 41 and the laminate brake 42 in the form of friction against the laminated core 2 by the radial preloading gravity. When the completed laminated core 2 reaches the lower end of the laminate brake 42, the laminated core is delivered to the conveying system 11 by gravity or a lift system there, and the conveying system conveys the completed laminated core 2 out of the punching press 9.

[0062] FIG. 8 exemplarily shows a dispenser 31 manufactured by a 3D printing method, which dispenser has a dispenser passage 50 located internally that introduces an adhesive medium from a supply section of the adhesive medium 34 to the dispenser 31 via an interface 51 or connection point. The adhesive medium is guided within the dispenser 31 via a passage system 50 to three separate interfaces 52 in this case, where it is delivered to an application head 32. Alternatively, there may be four or more or less than three separate interfaces. A special form of the dispenser passage 50 is advantageously manufactured from a thermosetting plastic by a 3D printing method.

Claims

1. A method for manufacturing a laminated core (2) from a metal sheet (1), comprising applying an adhesive medium as at least one adhesive point (22) onto the upper surface of a metal sheet insulator (21) of a metal sheet strip (5) guided horizontally with respect to the gravitational direction, through an application head (32) by an application unit (35), wherein the delivery of the adhesive medium as at least one adhesive point (22) onto the surface of the metal sheet insulator (21) of the metal sheet strip (5) or of a metal sheet (1) cut from the metal sheet strip is performed without a movable component within the application head (32), and for said delivery of the adhesive medium in the form of said at least one adhesive point (22), the application head (32) is moved perpendicular to the surface of the metal sheet strip (5), characterized by a method.

2. The method according to claim 1, wherein the application head (32) is moved synchronously with the working stroke of a punching press (9).

3. The method according to claim 1, wherein the application head (32) is moved without being synchronized with the working stroke of a punching press (9).

4. The method according to any one of claims 1 to 3, wherein the delivery of the adhesive medium as an adhesive point (22) onto the metal sheet insulator (21) of the metal sheet strip (5) or of the metal sheet (1) is assisted with or without using the adhesive force of the adhesive point (22) in the metal sheet strip (5) by the kinetic energy of a dispenser (31) of the application unit (35) and of the application head (32) and by the gravity of the adhesive medium.

5. The method according to any one of claims 1 to 4, wherein during the delivery of the adhesive medium, the application head (32) does not contact the surface of the metal sheet insulator (21) of the metal sheet strip (5) or of the metal sheet (1), and the distance between the application head (32) and the metal sheet strip (5) or the metal sheet (1) is at most 5 mm, preferably at most 1 mm.

6. The method according to any one of claims 1 to 5, wherein the surface of the metal sheet insulator (21) of the metal sheet (1) is only partially wetted during the application of the adhesive point (22).

7. The method according to any one of claims 1 to 6, wherein the application of the adhesive points (22) onto the metal thin-film insulator (21) or the metal thin-film (1) of the metal thin-film strip (5) is monitored by a sensor (33) with respect to the presence and size of partial wetting.

8. The method according to any one of claims 1 to 7, wherein the volume of each of the adhesive points (22) is adjusted.

9. The method according to any one of claims 1 to 8, wherein the volume of each of the adhesive points (22) is autonomously adjusted by a control circuit.

10. The application of a plurality of adhesive points (22) onto the surface of the metal thin-film strip (5) or the metal thin-film (1) is performed via at least one dispenser (31) having at least one supply section for the adhesive medium (34), and via at least one application head (32) connected to the at least one dispenser (31). The method according to any one of claims 1 to 9.

11. The application unit (35) for the application of the adhesive points (22) is located within the punching process (3). The method according to any one of claims 1 to 10.

12. The application unit (35) for the application of the adhesive medium (22) is located outside the punching process (3), in particular downstream of the punching process. The method according to any one of claims 1 to 10.

13. The application of the adhesive medium is performed by a configuration in which the dispenser (31) and the application head (32) are located inside the punching punch (43) of the punching tool (10). The method according to any one of claims 1 to 11.

14. An apparatus comprising an application unit (35) for manufacturing a laminated core (2) from a metal thin-film (1), the application unit having an application head (32), at least one dispenser (31) for the adhesive medium having at least one supply section for the adhesive medium (34), and a frame (30) for holding the dispenser (31) and at least one of the application heads (32). In the apparatus, The dispenser (31) is manufactured by an additional method, in particular by a 3D printing method. The apparatus is characterized by this.

15. The at least one dispenser (31) for the adhesive medium is made of a metal material. The apparatus according to claim 14.

16. The device according to claim 14, wherein the at least one dispenser (31) for the adhesive medium is made of a non-metallic material, in particular of plastic, preferably of thermosetting plastic.

17. The device according to any one of claims 14 to 16, wherein the coating head (32) does not include movable components, in particular driven components.

18. The device according to any one of claims 14 to 17, wherein a sensor (33), in particular an optical sensor (33), is provided for monitoring the presence and size of partial wetting of the metal sheet strip (5) or the metal sheet (1) having adhesive points (22), and the monitoring by the sensor (33) is carried out during or after the application of the adhesive medium.

19. The device according to any one of claims 14 to 18, wherein the volume of the adhesive point (22) is adjustable, and in particular is autonomously adjustable by a control circuit comprising a sensor (33) for monitoring the partial wetting of the metal sheet strip (5) or the metal sheet (1) having the adhesive point (22).

20. The device according to any one of claims 14 to 19, wherein the spacing between the coating heads (32) is at most 5 mm, preferably at most 3 mm, from each other.

21. A laminated iron core (2) made of a metal sheet (1), characterized in that the laminated iron core (2) is manufactured by the method according to any one of claims 1 to 13.

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