Method for resistance welding

Patent metadata

Field	Value
Publication number	US-12109642-B2
Application number	US-202117199904-A
Country	US
Kind code	B2
Filing date	Mar 12, 2021
Priority date	Apr 14, 2020
Publication date	Oct 8, 2024
Grant date	Oct 8, 2024

Abstract

A method for resistance welding includes performing a plurality of resistance welding processes during which welding electrodes are pressed against respective welding spots of respective workpieces. The welding electrodes are energized with a respective welding current for each of the plurality of resistance welding processes, and for each of the plurality of resistance welding processes, a respective at least one characteristic value that characterizes a quality of the welding is determined. A statistical analysis of the determined at least one characteristic value for each of the plurality of resistance welding processes is performed, and based upon the analysis, an adaptation of the prescribed welding parameters is determined.

First claim

What is claimed is:

1. A method for resistance welding, comprising:
performing a plurality of resistance welding processes;
pressing, during each of the plurality of resistance welding processes, welding electrodes against a respective welding spot of respective workpieces based upon respective prescribed welding parameters;
energizing the welding electrodes with a respective welding current for each of the plurality of resistance welding processes;
determining, for each of the plurality of resistance welding processes, a respective at least one characteristic value that characterizes a quality of the welding;
performing a statistical analysis of the determined at least one characteristic value for each of the plurality of resistance welding processes; and
determining, based upon the analysis, an adaptation of the prescribed welding parameters,
wherein the performing of the statistical analysis is performed based upon a median of spattering times at which welding spatter occurs during each of the plurality of resistance welding processes,
wherein the performing of the statistical analysis is performed based upon a dispersion of spattering times at which welding spatter occurs during each of the plurality of resistance welding processes, and
wherein the performing of the statistical analysis is performed based upon a difference of the median of the spattering times, and a product of a standard deviation of the spattering times at which welding spatter occurs during each of the plurality of resistance welding processes and a prescribable constant.

2. The method according to claim 1 , wherein the respective at least one characteristic value characterizes welding spatter spattering times at which welding spatter respectively occurs during the plurality of resistance welding processes.

3. The method according to claim 1 , wherein the performing of the statistical analysis is performed based upon a chi-square test, as to whether an occurrence of welding spatter during each of the plurality of resistance welding processes corresponds to a random distribution.

4. The method according to claim 1 , wherein the performing of the statistical analysis is performed based upon at least one of a material of the respective workpieces, and properties of the welding electrodes.

5. The method according to claim 1 , wherein the respective prescribed welding parameters comprise one or more of the parameters consisting of:
an electrode force;
a welding current;
a welding voltage;
a welding time;
a variation over time of an electrode force;
a variation over time of a welding current strength; and
a variation over time of a welding voltage.

6. The method of claim 1 , wherein a control unit is configured to:
perform the plurality of resistance welding processes;
press, during each of the plurality of resistance welding processes, welding electrodes against the respective welding spot of respective workpieces based upon respective prescribed welding parameters;
energize the welding electrodes with the respective welding current for each of the plurality of resistance welding processes;
determine, for each of the plurality of resistance welding processes, the respective at least one characteristic value that characterizes the quality of the welding;
perform the statistical analysis of the determined at least one characteristic value for each of the plurality of resistance welding processes; and
determine, based upon the analysis, the adaptation of the prescribed welding parameters.

7. A method for resistance welding, comprising:
performing a plurality of resistance welding processes;
pressing, during each of the plurality of resistance welding processes, welding electrodes against a respective welding spot of respective workpieces based upon respective prescribed welding parameters;
energizing the welding electrodes with a respective welding current for each of the plurality of resistance welding processes;
determining, for each of the plurality of resistance welding processes, a respective at least one characteristic value that characterizes a quality of the welding;
performing a statistical analysis of the determined at least one characteristic value for each of the plurality of resistance welding processes; and
determining, based upon the analysis, an adaptation of the prescribed welding parameters,
wherein the performing of the statistical analysis is performed based upon at least one of a number and a rate of instances of welding spatter that occur during the plurality of resistance welding processes.

8. A welding device, comprising:
a control unit configured to
perform a plurality of resistance welding processes,
press, during each of the plurality of resistance welding processes, welding electrodes against a respective welding spot of respective workpieces based upon respective prescribed welding parameters,
energize the welding electrodes with a respective welding current for each of the plurality of resistance welding processes,
determine, for each of the plurality of resistance welding processes, a respective at least one characteristic value that characterizes a quality of the welding,
perform a statistical analysis of the determined at least one characteristic value for each of the plurality of resistance welding processes, and
determine, based upon the analysis, an adaptation of the prescribed welding parameters,

wherein the performing of the statistical analysis is performed based upon a median of spattering times at which welding spatter occurs during each of the plurality of resistance welding processes,
wherein the performing of the statistical analysis is performed based upon a dispersion of spattering times at which welding spatter occurs during each of the plurality of resistance welding processes, and
wherein the performing of the statistical analysis is performed based upon a difference of the median of the spattering times, and a product of a standard deviation of the spattering times at which welding spatter occurs during each of the plurality of resistance welding processes and a prescribable constant.

9. The welding device of claim 8 , wherein the control unit is configured by executing a computer program.

10. The welding device of claim 9 , wherein the computer program is stored on a machine-readable storage medium.

Assignees

• Bosch Gmbh Robert

Inventors

• Zhou Baifan
• Shakirov Damir
• Bleier Fabian
• Haeufgloeckner Juergen
• Dieterle Martin
• Mcconnell Sean
• Slavnic Sinisa
• Pychynski Tim

Classifications

• B23K11/258 Primary

  the measured parameter being a voltage · CPC title

• B23K11/257

  the measured parameter being an electrical current · CPC title

• B23K11/255 Primary

  the measured parameter being a force (B23K11/253 takes precedence) · CPC title

• B23K11/115

  by means of two electrodes placed opposite one another on both sides of the welded parts · CPC title

• B23K11/36

  Auxiliary equipment (B23K11/31 takes precedence) · CPC title