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DE-102025145930-A1 - Method for manufacturing a lamination stack for an electric machine, and lamination stack

DE102025145930A1DE 102025145930 A1DE102025145930 A1DE 102025145930A1DE-102025145930-A1

Abstract

The invention relates to a method for manufacturing a laminated core (10) for an electric machine, in which, in the following sequence: an electrical steel sheet material is provided. At least one individual sheet (16) is produced from the electrical steel sheet material, wherein a contour of the at least one individual sheet (16) is manufactured. The at least one individual sheet (16) is subjected to at least one local mechanical post-treatment and/or at least one local heat treatment, thereby effecting a local increase in the strength of the at least one individual sheet (16). The local mechanical treatment and/or the local heat treatment takes place after the provision of the electrical sheet material, whereby this can then take place before the production of the individual sheet (16) and/or during the production of the individual sheet (16) and/or after the production of the individual sheet (16), and thus the local mechanical treatment and/or the local heat treatment belongs to the manufacturing step of the production of the individual sheet (16). The sheet metal stack (10) is then produced from the at least one single sheet (16), wherein the at least one single sheet (16) has already undergone local strength enhancement through local mechanical treatment and/or local heat treatment.

Inventors

  • Timo Knerr
  • Bernd Schietinger

Assignees

  • Mercedes-Benz Group AG

Dates

Publication Date
20260513
Application Date
20251107
Priority Date
20241108

Claims (8)

  1. A method for manufacturing a laminated core (10) for an electric machine, in which the following steps are carried out in the following sequence: - electrical steel sheet material is provided; - at least one individual sheet (16) is produced from the electrical steel sheet material, whereby a contour of the at least one individual sheet (16) is formed; - the at least one individual sheet (16) is subjected to at least one local mechanical post-treatment and/or at least one local heat treatment, thereby causing a local increase in the strength of the at least one individual sheet (16); and wherein the local mechanical treatment and/or the local heat treatment is carried out after the provision of the electrical steel sheet material, wherein this can then take place before the production of the individual sheet (16) and/or during the production of the individual sheet (16) and/or after the production of the individual sheet (16), and thus the local mechanical treatment and/or the local heat treatment is part of the manufacturing step of the production of the individual sheet (16), afterwards - the sheet stack (10) is produced from the at least one individual sheet (16), wherein a local increase in strength has already been effected on the at least one individual sheet (16) by the local mechanical treatment and/or the local heat treatment.
  2. Procedure according to Claim 1 characterized in that the contour is manufactured by punching, fine blanking, water jet cutting, laser cutting and/or electrical discharge machining (EDM).
  3. Procedure according to Claim 1 or 2 , characterized in that the local mechanical treatment and/or the local heat treatment of the at least one individual sheet (16) takes place in the interior of the contour and is covered in the sheet stack (10) by the adjacent individual sheets (16).
  4. Method of one of the preceding claims, characterized in that the local mechanical post-treatment comprises that at least one local forming and/or deformation of the at least one single sheet (16) is formed.
  5. Procedure according to Claim 4 , characterized in that the local transformation or deformation is a microindentation (18).
  6. Method according to one of the preceding claims, characterized in that the local mechanical post-treatment comprises local rolling and/or local plasticizing by pressing and/or local plasticizing by micro-indentation and/or local impregnation with a blasting medium.
  7. Procedure according to Claim 6 , characterized in that the local application of a blasting medium is a shot peening process.
  8. Laminated core (10) for an electric machine, wherein the laminated core is manufactured by a method according to one of the preceding claims.

Description

The invention relates to a method for manufacturing a laminated core for an electric machine. The invention also relates to a laminated core for an electric machine. The DE 10 2019 008 849 A1 A rotor lamination package for a rotor of an electric machine is known. Even the US 2023 / 0 129 960 A1 Figure 1 shows the rotor of an electric machine, where the rotor for a synchronous reluctance motor comprises several layers of laminations forming a stack. To generate the reluctance torque, the laminations are at least partially filled with a soft magnetic electrical conductor and possess at least one cavity enclosed by the conductor. By means of a process for mechanically deforming the outer areas of the rotor through compression, shot peening, or cold working, compressive, tensile, and shear stresses can be generated in the rotor across the stack of electrical steel sheets. The object of the present invention is to be able to realize a method for manufacturing a laminated core for an electric machine and a laminated core for an electric machine, such that particularly advantageous mechanical properties of the laminated core can be realized in a particularly advantageous manner. This problem is solved by a method with the features of claim 1 and by a sheet metal stack with the features of claim 8. Advantageous embodiments with expedient further developments of the invention are described in the remaining claims. A first aspect of the invention relates to a method for manufacturing a laminated core for an electric machine, in particular for a rotor and/or for a stator of an electric machine. If the laminated core is used for the rotor, it is also referred to as the rotor laminated core. If the laminated core is used for the stator, it is also referred to as the stator laminated core. For example, in the fully manufactured state of the electric machine, the laminated core supports at least one permanent magnet and/or at least one winding. In this process, an electrical sheet material, also known simply as electrical steel, is provided in sequence. At least one individual sheet is produced from this electrical sheet material, whereby a contour, in particular an outer contour and/or an inner contour, of the at least one individual sheet is manufactured, that is, formed. In this process, the at least one individual sheet is subjected to at least one local mechanical post-treatment and/or at least one local heat treatment, which results in a local increase in the strength of the at least one individual sheet. The local mechanical treatment and/or the local heat treatment takes place after the electrical steel sheet material has been provided, whereby this can then take place before the production of the individual sheet and/or during the production of the individual sheet and/or after the production of the individual sheet, and thus the local mechanical treatment and/or the local heat treatment belongs to the manufacturing step of the production of the individual sheet. While this can also be done in a machine, as is common in stamping and packaging, where electrical steel sheet material is supplied, usually unwound from a spool, and then the contour is produced in a directly subsequent step, the invention comes into play here. It adds a local mechanical treatment and/or local heat treatment to the contour production step, allowing the surface of the electrical steel sheet material within the contour to be directly processed. This processing through local mechanical treatment and/or local heat treatment can, for example, take place directly before or after the contour production, but also during and especially during multi-stage contour production, as is common in stamping, local treatment can be carried out directly between the individual production steps. Thus, the treatment can begin even before the contour production and continue until after the contour production, so that, in principle, local mechanical treatment and/or local heat treatment can be performed at any time during the contour production step of the individual sheet. The key advantage of performing local mechanical treatment and/or local heat treatment during the manufacturing step of the individual sheet's contour is primarily the accessibility of the inner areas of the contour. These areas are no longer accessible for local processing after the lamination stack has been manufactured from a stack of individual sheets, as they lie within the contour and are thus covered by the adjacent individual sheets in the stack. Above all, this invention enables the local mechanical treatment and/or local heat treatment of inner areas of the electrical steel sheet's contour, which is no longer possible with a finished rotor or lamination stack. After the stack is complete, these areas are no longer accessible from the outside. The sheet metal stack is then manufactured from at least one individual sheet, wherein a local increase in strength has already been achieved