US-12627109-B2 - Semi-finished product provided with a window for laser welding for manufacturing an electrical contact element, method for manufacturing an electrical contact element and electrical contact element

Abstract

A semi-finished product for manufacturing an electrical contact element includes a first workpiece having a front side and a rear side opposite the front side, a second workpiece, and a window extending through the first workpiece. The first workpiece and the second workpiece are both metallic. The rear side of the first workpiece is closer to the second workpiece than the front side. Through the window, a surface of the second workpiece is accessible from the first workpiece. The window has a base area that, starting at the front side of the first workpiece, increases toward the second workpiece.

Inventors

• Willi Dietrich
• Soenke Sachs

Assignees

• TE CONNECTIVITY GERMANY GMBH

Dates

Publication Date

20260512

Application Date

20220902

Priority Date

20210903

Claims (19)

1. 1 . A semi-finished product for manufacturing an electrical contact element, comprising: a first workpiece having a front side and a rear side opposite the front side; a second workpiece, the first workpiece and the second workpiece are both metallic, the rear side of the first workpiece is closer to the second workpiece than the front side; and a window extending through the first workpiece and through which a surface of the second workpiece is accessible from the first workpiece, the window has a base area that, starting at the front side of the first workpiece, increases toward the second workpiece, the surface of the second workpiece that is accessible through the window is within an undercut formed in the second workpiece.
2. 2 . The semi-finished product of claim 1 , wherein a light trap extends between a boundary surrounding the window on the front side of the first workpiece and the surface of the second workpiece that is accessible through the window.
3. 3 . The semi-finished product of claim 2 , wherein the light trap forms a gap between the first workpiece and the second workpiece.
4. 4 . The semi-finished product of claim 2 , wherein a surface of the first workpiece defining the light trap has a microstructure.
5. 5 . The semi-finished product of claim 1 , wherein one of the first workpiece and the second workpiece is a piece of sheet metal.
6. 6 . The semi-finished product of claim 5 , wherein the other of the first workpiece and the second workpiece is a contact part for the electrical contact element.
7. 7 . The semi-finished product of claim 1 , wherein the surface of the second workpiece that is accessible through the window has a surface structure.
8. 8 . The semi-finished product of claim 7 , wherein the surface of the second workpiece that is accessible through the window has a convex curvature.
9. 9 . The semi-finished product of claim 7 , wherein the surface of the second workpiece that is accessible through the window has a microstructure.
10. 10 . An electrical contact element, comprising: a semi-finished product including: a first workpiece having a front side and a rear side opposite the front side; a second workpiece, the first workpiece and the second workpiece are both metallic, the rear side of the first workpiece is closer to the second workpiece than the front side; and a window extending through the first workpiece and through which a surface of the second workpiece is accessible from the first workpiece, the window has a base area that, starting at the front side of the first workpiece, increases toward the second workpiece, the surface of the second workpiece that is accessible through the window is within an undercut formed in the second workpiece.
11. 11 . The electrical contact element of claim 10 , wherein the first workpiece is joined with the second workpiece in a positive substance-fit manner at an edge of the window by a weld spot.
12. 12 . The electrical contact element of claim 10 , wherein the first workpiece is a contact body and the second workpiece is a contact part.
13. 13 . The electrical contact element of claim 12 , wherein the contact body is formed from a piece of sheet metal by metal forming.
14. 14 . The electrical contact element of claim 12 , wherein the contact part is arranged at least in part in the contact body and is joined to the contact body by a weld spot.
15. 15 . A method for joining, comprising: providing a first workpiece having a front side and a rear side opposite the front side; providing a second workpiece; arranging the rear side of the first workpiece closer to the second workpiece than the front side; and directing a laser beam through a window extending at least through the first workpiece onto the second workpiece, the laser beam is reflected from the second workpiece onto the rear side of the first workpiece, the window on the front side of the first workpiece has a base area and a surface normal that is perpendicular to the base area, an angle of less than 45° is formed between the laser beam and the surface normal.
16. 16 . The method of claim 15 , wherein one of the first workpiece and the second workpiece is a piece of sheet metal and the other of the first workpiece and the second workpiece is a pre-formed contact part for an electrical contact element.
17. 17 . The method of claim 16 , further comprising joining the pre-formed contact part with the piece of sheet metal at a weld spot by laser welding.
18. 18 . The method of claim 17 , wherein the piece of sheet metal is shaped around the pre-formed contact part.
19. 19 . The method of claim 15 , wherein the first workpiece and the second workpiece are both pre-formed parts and are placed against or into one another to form a semi-finished product before being joined with one another by laser welding a weld spot.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of the filing date under 35 U.S.C. § 119(a)-(d) of German Patent Application No. 102021122892.1, filed on Sep. 3, 2021. FIELD OF THE INVENTION The invention relates to a semi-finished product for manufacturing an electrical contact element and a method for joining a first metallic workpiece with a second metallic workpiece by way of laser welding. BACKGROUND Electrical contact elements are known. They can be used to establish an electrically conductive connection in connectors. An electrical contact element can comprise, for example, a contact pin or a receptacle for a contact pin. Electrical contact elements are often composed of several parts. This allows the individual parts to be manufactured according to the properties demanded, such as electrical conductivity, corrosion resistance, abrasion resistance, or elasticity. The two parts are referred to as workpieces during the manufacture of the electrical contact element. In general, the two workpieces are manufactured separately to a certain extent and mated or joined at a certain point in time in the manufacturing process. The arrangement of the workpieces that are mated or joined or to be joined is referred to as a semi-finished product, regardless of the degree of completion of the individual workpieces. The electrical contact element is then manufactured from the semi-finished product. Depending on the field of use of the electrical contact element, it can be necessary for the two parts of the contact element to be electrically conductively and/or mechanically connected to one another. In particular, in mass production, this connection can be complex and therefore expensive. SUMMARY A semi-finished product for manufacturing an electrical contact element includes a first workpiece having a front side and a rear side opposite the front side, a second workpiece, and a window extending through the first workpiece. The first workpiece and the second workpiece are both metallic. The rear side of the first workpiece is closer to the second workpiece than the front side. Through the window, a surface of the second workpiece is accessible from the first workpiece. The window has a base area that, starting at the front side of the first workpiece, increases toward the second workpiece. BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described by way of example with reference to the accompanying Figures, of which: FIG. 1 is a sectional side view of an electrical contact element according to an embodiment; FIG. 2 is a sectional side view of a semi-finished product for producing the electrical contact element; FIG. 3 is a schematic detail view of a semi-finished product in a region of a window; FIG. 4 is a top view of the window of FIG. 3; FIG. 5 is a schematic detail view of the window of FIG. 3 with weld points introduced; FIG. 6 is a schematic detail view of a window according to a second embodiment; FIG. 7 is a schematic detail view of a window according to a third embodiment; FIG. 8 is a top view of the window of FIG. 7; FIG. 9 is a schematic detail view of a semi-finished product according to another embodiment; and FIG. 10 is a schematic sectional view of a semi-finished product according to another embodiment. DETAILED DESCRIPTION OF THE EMBODIMENT(S) The invention shall be explained hereafter in more detail by way of example using embodiments with reference to the drawings. The feature combinations illustrated in the embodiments by way of example can be supplemented by further features in accordance with the properties of the devices of the invention that are demanded for a specific application. Individual features can also be omitted in the embodiments described if the effect of this feature is irrelevant for a specific case of application. The same reference numerals in the drawings are used for elements having the same function and/or the same structure. FIG. 1 shows an electrical contact element 1 merely by way of example in a longitudinal sectional view and schematically. The electrical contact element 1 is composed of two parts, a contact body 3 and a contact part 5 arranged within contact body 3. Contact part 5 is shown only by way example as a spring 7 which can receive a contact part 9 of a mating contact element 11 configured to be complementary (in FIG. 1 indicated by dashed lines) to establish an electrically conductive connection thereto. As an alternative, electrical contact element 1 can comprise a pin, a flat contact, or any other suitable structure instead of a spring 7. The contact body 3 can form a cage for the contact part 5 and, for example, assume a support function. Contact body 3 comprises crimping wings 13 for connecting contact element 1 to an electrical line. Contact body 3 consequently serves not only to receive contact part 5, but also to provide the electrical connection between a line received in crimping wings 13 and contact part 5. In o