CN-115298942-B - Method for manufacturing rotor and rotor

Abstract

The invention relates to a method for producing a rotor, in particular for a current-excited electrical machine, comprising the steps of providing a plurality of sheet elements and arranging the sheet elements into a lamination stack having a plurality of webs, arranging end disks on the lamination stack on the end side, the end disks being designed to axially support the lamination stack, axially fixing or pre-tensioning the lamination stack by winding the webs with a conductor material, arranging the rotor shaft in the fixed or pre-fixed lamination stack, in particular by means of a compression joint or a transverse joint.

Inventors

• A. Jank
• F. Baker
• D Alinsiman

Assignees

• 宝马股份公司

Dates

Publication Date

20260508

Application Date

20210419

Priority Date

20200514

Claims (12)

1. 1. A method for manufacturing a rotor, the method comprising the steps of: -providing a plurality of sheet elements and arranging the sheet elements into a lamination stack (10), said lamination stack (10) having a plurality of slats (14); -arranging an end disc (20) on the end side on the lamination stack (10), the end disc (20) being designed to axially support the lamination stack (10); -axially pre-stressing the lamination stack (10) with a sufficient pre-stressing force by winding the strips (14) with a conductor material, so that the strips are prevented from deforming when cooling the lamination stack after joining the rotor shaft; -arranging the rotor shaft (60) in a fixed or pre-fixed lamination stack (10).
2. 2. The method of claim 1, wherein the sheet element is stamped and has a stamping burr, the method comprising the steps of: -orienting the sheet elements in the lamination stack (10) such that the punching burrs are oriented in a preferential direction; -providing a void in the end disc (20) oriented towards the preferential direction so as to absorb the deformation of the lamination stack (10) in the region of the rotor shaft (60).
3. 3. A method according to claim 2, wherein the method comprises the steps of: -orienting the sheet elements in the lamination stack (10) such that the punching burrs are alternately oriented.
4. 4. A method according to any one of claims 2 to 3, wherein the method comprises the steps of: -arranging a rotor shaft (60) along the preferential direction.
5. 5. A method according to any one of claims 1 to 3, wherein the method comprises the steps of: -arranging the rotor shaft (60) in the engagement direction (F) until a target position is reached, which is located before the final position with respect to the engagement direction (F).
6. 6. A method according to any one of claims 1 to 3, wherein the method comprises the steps of: -pre-fixing the lamination stack (10) in radial direction during winding.
7. 7. The method of claim 1, wherein the rotor is a rotor for a current excited machine.
8. 8. Method according to claim 1, wherein the rotor shaft (60) is arranged in a fixed or pre-fixed lamination stack (10) by means of compression or transverse engagement.
9. 9. Rotor comprising a lamination stack (10) consisting of a plurality of sheet elements and a plurality of strips (14), wherein an end disc (20) is arranged on the lamination stack (10) on the end side, said end disc (20) being designed to axially support the lamination stack (10), a conductor material is wound around the strips (14) with sufficient pre-tension so that deformation of the strips is avoided upon cooling the lamination stack after joining the rotor shaft, the rotor shaft (60) is arranged in the lamination stack (10), and at least one end disc (20) has a recess (22) designed to absorb axial deformation of the lamination stack (10).
10. 10. Rotor according to claim 9, wherein the lamination stack (10) is axially preloaded in the region of its strips (14) by windings (40).
11. 11. A rotor according to claim 9 or 10, wherein the sheet element has a punching burr which is oriented towards the recess (22).
12. 12. An electric motor comprising a rotor manufactured by the method according to any one of claims 1 to 8.

Description

Method for manufacturing rotor and rotor Technical Field The present invention relates to a method for producing a rotor, in particular of a current-excited machine, and to a rotor for a current-excited machine. Background In order to avoid eddy current losses, the sheet metal laminate of the type described is composed of thin, stamped sheet metal pieces. The arrangement of the rotor shaft in such sheet metal laminations is generally achieved by means of an extrusion joint, wherein the sheet metal laminations are heated and the rotor shaft is cooled. This is not without problems, because the sheet material pieces deform on cooling due to the stresses induced during stamping. Without support or axial clamping, the sheet stack can then tip or bulge sideways. To compensate for this undesirable effect, such sheet metal laminates are usually clamped axially by means of screw connections or by means of additional components. However, this is costly in terms of manufacturing technology, increases costs and furthermore requires additional installation space. Disclosure of Invention The object of the present invention is therefore to provide a method for producing a rotor and a rotor which eliminate the above-mentioned disadvantages and which are simple to construct and can be implemented in a cost-effective manner. To this end, the invention proposes a method for producing a rotor, comprising the steps of providing a plurality of sheet elements and arranging the sheet elements into a lamination stack having a plurality of webs, arranging an end disk on the lamination stack at the end side, the end disk being designed to axially support the lamination stack, axially pre-stressing the lamination stack with sufficient pre-stressing force by winding the webs with a conductor material, such that deformation of the webs is avoided when cooling the lamination stack after joining the rotor shaft, arranging the rotor shaft in a fixed or pre-fixed lamination stack. The invention also proposes a rotor comprising a lamination stack of a plurality of sheet elements and a plurality of strips, wherein an end disk is arranged on the lamination stack on the end side, said end disk being designed to support the lamination stack axially, the conductor material being wound around the strips with sufficient preload so that deformation of the strips is avoided when the lamination stack is cooled after joining the rotor shaft, the rotor shaft being arranged in the lamination stack, and at least one end disk having a recess designed to absorb axial deformation of the lamination stack. The invention also proposes an electric motor comprising a rotor manufactured by the method according to the invention. According to the invention, the method for manufacturing a rotor, in particular for a current-excited electrical machine, comprises the following steps: -providing a plurality of sheet elements and arranging the sheet elements into a stack of sheets having or forming a plurality of strips; -arranging end discs on the lamination stack on the end side, the end discs being designed to axially support the lamination stack; -axially fixing or pre-tightening the lamination stack by winding the strips or end plates with a conductor material; The rotor shaft is arranged in a fixed or pre-tensioned stack of laminations, in particular by means of a press-fit or transverse-fit. Advantageously, the rotor-side winding is arranged completely or at least partially before the rotor shaft is arranged on the lamination stack, in order to achieve an in particular axial pretensioning of the rotor shaft. In other words, the structure comprising the lamination stack and the end disk arranged on the end side is preloaded or fastened, in particular axially preloaded or fastened, by the winding being arranged completely or at least partially or partially, in such a way that no deformation occurs during cooling of the lamination stack after joining the rotor shaft. The rotor shaft is expediently arranged or joined in the lamination stack by means of a press joint. Accordingly, a press fit is effected between the respective openings of the lamination stack and the rotor shaft. Preferably, a transverse crimping structure is realized. Prior to assembly, the rotor shaft is cooled and the lamination stack is correspondingly heated. The possible deformations, in particular in the strip regions of the lamination stack, are effectively avoided or compensated for by the pretensioning applied by the winding. According to a preferred embodiment, a wire-shaped conductor material is used as the conductor material, for example a copper wire having a round (rund), in particular a round (kreisrund), cross section. In order to achieve a good pretension, the end disk is expediently constructed in a correspondingly curved and rigid manner. Preferred materials are metallic materials, such as aluminum or alloys thereof. Depending on cost objectives, the end disc can be a machined (metal