Method for producing an electromagnetic component, in particular a laminated core, for example a stator core or a rotor core, for an electric machine

Patent metadata

Field	Value
Publication number	US-2022239203-A1
Application number	US-202017612049-A
Country	US
Kind code	A1
Filing date	Jan 17, 2020
Priority date	May 20, 2019
Publication date	Jul 28, 2022
Grant date	—

Abstract

The invention relates to a method for producing an electromagnetic component. In particular, the electromagnetic component to be produced can be a laminated core, for example a stator core or a rotor core, and can be provided for use with an electric machine such as an electric motor.
The method has the following steps:
A) providing a metal sheet as a starting material; B) punching out a number of lamellae from the metal sheet; C) heat-treating the lamellae; D) joining the heat-treated lamellae to form the component or a portion of the component.

The invention also relates to an electric machine.

First claim

1 . A method for producing an electromagnetic component including at least of a laminated core, a stator core or a rotor core, for an electric machine, the method comprising:
providing a metal sheet as a starting material, punching out a number of lamellae from the metal sheet, heat-treating the number of lamellae to provide heat-treated lamellae, and joining the heat-treated lamellae to form the electromagnetic component or a portion of the electromagnetic component.

2 . The method according to claim 1 , wherein the joining of the heat-treated lamellae comprises, sequentially for each of the heat-treated lamellae, the following steps:
applying a thermally activated adhesive to a surface of the heat-treated lamella, substantially over the whole surface, to form an adhesive coating, and activating the adhesive of the adhesive coating, wherein the heat-treated lamellae having the activated adhesive are superimposed in a position-aligned and angularly aligned manner and are subjected, on their end face, to a compressive force acting in an axial direction.

3 . The method according to claim 2 , wherein the activating the adhesive includes illuminating the adhesive coating with infrared radiation using a means for emitting infrared radiation.

4 . The method according to claim 3 , wherein the illuminating the adhesive coating is carried out in an NIR wavelength range.

5 . The method according to claim 3 , wherein the means for emitting infrared radiation are, in terms of the processing sequence, arranged between a punching tool and an ejection punch, and includes:
at least one upper lamp which is directed in a punching direction onto a first lamella surface or at least one lower lamp which is directed against a punching direction onto a second lamella surface present on the other side of the punching tool, or both at least one upper and at least one lower lamp.

6 . The method according to claim 1 , wherein the joining of the heat-treated lamellae comprises, sequentially for each of the heat-treated lamellae of the number of lamellae, the following steps:
applying a thermally activated adhesive to a surface of the lamella, substantially over the whole surface, to form an adhesive coating, superimposing the heat-treated lamellae in a position-aligned and angularly aligned manner, applying a compressive force acting in an axial direction to the end face of the superimposed lamellae, and heating the superimposed lamellae, which are at least temporarily subjected to the compressive force, for a predetermined period of time at a predetermined temperature to activate the adhesive of the adhesive coating.

7 . The method according to claim 6 , wherein the predetermined period of time is between 5 minutes and 60 minutes.

8 . The method according to claim 6 , wherein the predetermined temperature is between 100° C. and 250° C.

9 . The method according to claim 6 , further comprising inspecting the adhesive coating using an optical inspection method and a respective heat-treated lamella is only used in the joining process if the optical inspection method detects a sufficiently uniform thickness distribution of the adhesive coating, and otherwise the respective heat-treated lamella is removed from the method as a reject.

10 . The method according to claim 6 , further comprising inspecting the adhesive coating using an optical inspection method, wherein the optical inspection method is the capture of a thermal image of the adhesive coating, which is not-yet-dry, by means of a thermal imaging camera.

11 . The method according to claim 1 , wherein the metal sheet
is a panel made from an electrical steel strip or is an electrical steel strip or is a panel or a strip made of a soft magnetic material.

12 . The method according to claim 1 , wherein the metal sheet consists of a non-grain-oriented electrical steel strip.

13 . The method according to claim 11 , wherein the metal sheet, in addition to Fe and unavoidable impurities, consists of in wt. %:
0.1 to 3.50 Si, 0.01 to 1.60 Al, 0.07 to 0.65 Mn, and up to 0.25 P, wherein the sum of all components including unavoidable impurities is 100 wt. %.

14 . The method according to claim 12 , wherein
the heat treatment is carried out as stress relief annealing.

15 . The method according to claim 1 , wherein a thermally activated adhesive is applied on both surfaces of the lamella.

16 . The method according to claim 15 , wherein the thermally activated adhesive contains:
60 parts by weight of an epoxy resin, 0.5 to 15 parts by weight of a latent hardener, 1 to 15 parts by weight of a latent accelerator.

17 . An electric machine,
having a first electromagnetic component and a second electromagnetic component, wherein the first electromagnetic component is produced using the method according to claim 1 and wherein the second electromagnetic component is joined as a laminated core consisting of lamellae, wherein the lamellae of the second electromagnetic component are not subjected to any heat treatment after being punched out of another metal sheet provided as a starting material, the first electromagnetic component being a stator and the second electromagnetic component being a rotor of the electric machine.

18 . An electrical component or laminated core, produced using the method according to claim 1 .

19 . An electric machine having electrical components according to claim 18 .

20 . An electric machine according to claim 19 , configured as an electric motor for a passenger car, a truck, a motorized two-wheeler, a small electric vehicle, an aircraft or a drone.

Assignees

• Thyssenkrupp Steel Europe Ag

Inventors

• Lewe Tobias
• Machalitza Karsten
• Kamen Volker
• Tietz Marco

Classifications

• H01F41/0233

  Manufacturing of magnetic circuits made from sheets (magnetic cores made from sheets H01F27/245; soft magnetic alloys in the form of sheets H01F1/16) · CPC title

• H02K15/02 Primary

  of stator or rotor bodies · CPC title

• H02K1/148

  Sectional cores (H02K1/141 takes precedence) · CPC title