Welding electrode with contoured face

Patent metadata

Field	Value
Publication number	US-9682439-B2
Application number	US-201313777345-A
Country	US
Kind code	B2
Filing date	Feb 26, 2013
Priority date	Sep 28, 2006
Publication date	Jun 20, 2017
Grant date	Jun 20, 2017

Abstract

A welding electrode for resistance spot welding includes a weld face comprising rings of ridges that project outwardly from a base surface of the weld face. The rings of ridges are positioned on the weld face to contact and impress into a sheet metal workpiece surface during resistance spot welding. If the welding electrode is used during resistance spot welding of light metal alloy workpieces, such as those of aluminum alloy or magnesium alloy, the rings of ridges on the weld face can contribute to improved welding performance.

First claim

The invention claimed is:

1. A welding electrode comprising a body with a round, spherically domed weld face for contact of the spherically domed face with a workpiece in an electrical resistance welding operation, the spherically domed weld face comprising concentric circular rings of ridges that are separated by surfaces of the spherically domed weld face such that the concentric circular rings of ridges are spaced from each other radially from a center of the spherically domed weld face, the concentric circular rings of ridges being positioned to contact and impress into a workpiece surface with each of the individual ridges projecting outwardly from the surfaces of the spherically domed weld face that are adjacent thereto, the concentric circular rings of ridges having height dimensions in the range of twenty micrometers to two hundred micrometers and spacings between ridge heights in the range of eighty micrometers to fifteen hundred micrometers, and wherein the material of the concentric circular rings of ridges is susceptible to degradation in welding operations.

2. The welding electrode as recited in claim 1 in which the concentric circular rings of ridges are formed in the weld face with a cutting tool.

3. The welding electrode as recited in claim 1 in which each of the individual ridges projects outwardly, with a constant semicircular cross-sectional profile, from the surfaces of the spherically domed weld face that are adjacent thereto.

4. The welding electrode as recited in claim 1 in which the concentric circular rings of ridges have a constant triangular cross-sectional profile.

5. The welding electrode as recited in claim 1 in which the concentric circular rings of ridges have a constant sinusoidal cross-sectional profile.

6. A welding electrode for resistance spot welding a sheet metal workpiece that comprises two or more sheet metal layers, the welding electrode comprising:
a body; and
a domed weld face configured at one end of the body to contact a sheet metal workpiece surface, the weld face comprising a base surface that has a center and three or more radially-spaced circular ridges that surround the center of the base surface and project outwardly from the base surface, the three or more circular ridges being positioned on the weld face to contact and impress into the sheet metal workpiece surface during resistance spot welding, and each of the three or more circular ridges having a cross-sectional profile raised above the base surface such that each of the ridges projects outwardly from the base surface to a height between about 20 μm to 200 μm, the cross-sectional profile of each circular ridge being constant throughout a circumference of the ridge that surrounds the center of the base surface.

7. The welding electrode as recited in claim 6 , wherein the three or more circular ridges include spacings between each of the circular ridges that range from about 80 μm to about 1500 μm.

8. The welding electrode as recited in claim 6 , wherein the welding electrode is composed of a copper alloy.

9. The welding electrode as recited in claim 6 , wherein the cross-sectional profile of each of the three or more circular ridges is semicircular.

10. The welding electrode as recited in claim 6 , wherein the base surface of the welding electrode has a radius of curvature that ranges from about 20 mm to about 150 mm.

Assignees

• Gm Global Tech Operations Llc

Inventors

• Sigler David R
• Karagoulis Michael J

Classifications

• Y10T82/16442

  with means to circumrotate tool[s] about work · CPC title

• Y10T407/19

  Rotary cutting tool · CPC title

• B23K11/14

  Projection welding · CPC title

• B23B5/166

  Devices for working electrodes · CPC title

• Y10T83/9372

  Rotatable type · CPC title