METHOD FOR CONNECTING FLAT WIRE ENDS AND STATOR PRODUCED IN SUCH A WAY

• US 20190326801A1
• Filed: 08/28/2017
• Published: 10/24/2019
• Est. Priority Date: 10/24/2016
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Hein, Tobias, Lange, Fabian, Ermer, Martin
• Granted Patent: US 11,101,720 B2
• Time in Patent Office: Days
• CPC Class Codes: B23K 2101/36 Electric or electronic devices
• CPC Class Codes: B23K 26/22 Spot welding
• CPC Class Codes: H02G 1/12 for removing insulation or armouring from cables, e.g. from the end thereof
• CPC Class Codes: H02K 15/0081 for form-wound windings
• CPC Class Codes: H02K 2213/03 Machines characterised by numerical values, ranges, mathematical expressions or similar information
• CPC Class Codes: H02K 3/12 arranged in slots
• CPC Class Codes: H02K 3/14 with transposed conductors, e.g. twisted conductors

Abstract

The invention relates to a method for connecting free flat wire ends (4, 5) with a substantially rectangular cross section with four sides (41, 42, 43, 44) of a stator of an electrical machine, comprising the steps at: stripping a first flat wire end (4), sheathed with an insulation material, such that partial stripping is carried out at least on three sides (41, 42, 43) and such that the insulation material remains complete on a fourth side (44) of the first flat wire end (4), and electrically connecting the stripped first flat wire end (4) on the completely stripped side (43) to a second flat wire end (5).

Claims

1. A method for connecting free flat wire ends (4, 5), each having an essentially rectangular cross section, of a stator of an electrical machine, the method comprising the steps:

providing a first flat wire end (4) which has an essentially rectangular cross section and which is coated with an insulation material on first, second, third and fourth sides (41, 42, 43, 44),

at least partially stripping of the first flat wire end (4) on three of the sides (41, 42, 43) to provide a stripped first flat wire end (4) with the third side (43) being fully stripped, wherein the insulation material remains completely intact on the fourth side (44) of the stripped first flat wire end (4), and

providing an electrical connection of the stripped first flat wire end (4) on the fully stripped side (43) to a second flat wire end (5).

2. The method as claimed in claim 1, wherein the first side (41) and the second side (42) of the stripped first flat wire end (4) are only partially stripped to an extent H, starting from a free end of the first flat wire end (4), and the third side (43) of the stripped first flat wire end (4) is fully stripped to the extent H.

3. The method as claimed in claim 2, wherein stripped surfaces on the first side (41) and the second side (42) are identical in size.

4. The method as claimed in claim 2, wherein a boundary line (8) between a stripped region (6) and an insulated region (7) of the first flat wire end (4) is arched.

5. The method as claimed in claim 1, characterized in that the second flat wire end (5) is stripped in the same way as the first flat wire end (4).

6. The method as claimed in claim 1, wherein the first and second flat wire ends (4, 5) are connected to one another without using an additional material.

7. The method as claimed in claim 1, wherein the electrical connection is provided by a thermal joining process.

8. The method as claimed in claim 7, wherein a welding device for establishing the electrical connection between the first and second flat wire ends (4, 5) is moved back and forth several times in a linear manner.

9. The method as claimed in claim 1, wherein a multiplicity of flat wire ends are arranged in a row and connected to one another, and wherein the first flat wire end (4) and a last flat wire end (5) of the row of flat wire ends are stripped in such a way that the insulation material is at least partially stripped on three sides of the first and last flat wire ends and remains intact on the fourth side.

10. A method of producing a stator of an electrical machine, the method comprising providing a flat wire connection according to the method as claimed in claim 1.

11. The method as claimed in claim 10, wherein adjacent flat wires (4, 5) are connected to each other by means of a melting (10) in such a way that a spacing (A) of each point of a boundary line (8) between a stripped region (6) and an insulated region (7) of the flat wire ends perpendicular to a tangent on the boundary line (8) is identical in size up to an edge point (R) of the melting (10).

13. The method as claimed in claim 2, wherein a boundary line (8) between a stripped region (6) and an insulated region (7) of the first flat wire end (4) is circularly arched or parabolic.

14. The method as claimed in claim 1, wherein the electrical connection is provided by welding.

15. The method as claimed in claim 1, wherein the electrical connection is provided by laser welding.

12. A stator of an electrical machine, comprising a flat wire connection including a stripped first flat wire end (4) with first and second sides (41, 42) being partially stripped of insulation material and a third side (43) being fully stripped of insulation material, wherein the insulation material remains completely intact on a fourth side (44) of the stripped first flat wire end (4), and wherein the stripped first flat wire end (4) is electrically connected on the fully stripped side (43) to a second flat wire end (5).