Resistance welding apparatus and resistance welding method for the resistance welding of at least one component

Patent metadata

Field	Value
Publication number	US-12220759-B2
Application number	US-202016836145-A
Country	US
Kind code	B2
Filing date	Mar 31, 2020
Priority date	Apr 9, 2019
Publication date	Feb 11, 2025
Grant date	Feb 11, 2025

Abstract

A resistance welding apparatus includes a welding tool with a welding electrode configured to contact a component. A welding transformer is configured to feed an electric current to the welding tool and a control device is configured to control a polarity of welding transformer by transmitting polarity information to the welding transformer such that a polarity of the welding transformer is switchable. A circuit including two transistors is operably connected in series between the welding tool and an output of the welding transformer and a polarity one of the transistors is rotated relative to the other transistor, such that a polarity of a welding voltage at the welding electrode is switchable with the switching of the polarity of the welding transformer, and such that a polarity of a welding current at the welding transformer is switchable with the switching of the polarity of the welding transformer.

First claim

What is claimed is:

1. A resistance welding apparatus for the resistance welding of at least one component, comprising:
a welding tool comprising a first welding electrode and a second welding electrode each configured to contact the at least one component and to receive a polarity-switchable electric welding current for welding the at least one component;
at least one welding transformer configured to output at least one secondary voltage;
a rectifier circuit operably connected to the at least one welding transformer and the welding tool, the rectifier circuit including a first transistor and a second transistor connected in series between the first welding electrode and a secondary winding of the at least one welding transformer to receive the at least one secondary voltage, the rectifier circuit configured to output the polarity-switchable electric welding current to the welding tool during the welding of the at least one component;
a control device configured to control a polarity of the at least one welding transformer by transmitting polarity information directly to the at least one welding transformer through at least one first line connecting the control device to a primary winding of the at least one welding transformer; and
a polarity switching device of the at least one welding transformer operably connected to the first transistor and the second transistor of the rectifier circuit, the polarity switching device configured to receive the polarity information that is applied to the at least one welding transformer through the at least one first line,
wherein the polarity switching device is configured to switch a polarity of the at least one welding transformer based on the polarity information by driving the first transistor and the second transistor to output the polarity-switchable electric welding current from the rectifier circuit,
wherein a polarity of the first transistor is opposite a polarity of the second transistor in the series connection of the first transistor and the second transistor, such that a polarity of a welding voltage at the first welding electrode is switchable with the switching of the polarity of the at least one welding transformer as performed by the polarity switching device, and such that a polarity of the polarity-switchable electric welding current is switchable with the switching of the polarity of the at least one welding transformer as performed by the polarity switching device, and
wherein the polarity information is a polarity of an AC voltage carried by the at least one line that is applied to the primary winding of the at least one welding transformer for the generation of the polarity-switchable electric welding current and the welding voltage.

2. An installation for the manufacture of a joined device, comprising:
a welding tool comprising a first welding electrode and a second welding electrode each configured to contact at least one component and to receive a polarity-switchable electric welding current for welding the at least one component;
at least one welding transformer configured to output at least one secondary voltage;
a rectifier circuit operably connected to the at least one welding transformer and the welding tool, the rectifier circuit including a first transistor and a second transistor connected in series between the first welding electrode and a secondary winding of the at least one welding transformer to receive the at least one secondary voltage, the rectifier circuit configured to output the polarity-switchable electric welding current to the welding tool during the welding of the at least one component;
a control device configured to control a polarity of the at least one welding transformer by transmitting polarity information directly to the at least one welding transformer through at least one first line connecting the control device to a primary winding of the at least one welding transformer; and
a polarity switching device of the at least one welding transformer operably connected to the first transistor and the second transistor of the rectifier circuit, the polarity switching device configured to receive the polarity information that is applied to the at least one welding transformer through the at least one first line,
wherein the polarity switching device is configured to switch a polarity of the at least one welding transformer based on the polarity information by driving the first transistor and the second transistor to output the polarity-switchable electric welding current from the rectifier circuit,
wherein a polarity of the first transistor is opposite a polarity of the second transistor in the series connection of the first transistor and the second transistor, such that a polarity of a welding voltage at the welding electrode is switchable with the switching of the polarity of the at least one welding transformer as performed by the polarity switching device, and such that a polarity of the polarity-switchable electric welding current is switchable with the switching of the polarity of the at least one welding transformer as performed by the polarity switching device, and
wherein the polarity information is a polarity of an AC voltage carried by the at least one line that is applied to the primary winding of the at least one welding transformer for the generation of the polarity-switchable electric welding current and the welding voltage.

3. The resistance welding apparatus according claim 1 , wherein the at least one welding transformer comprises:
a first transformer; and
a second transformer, the second transformer electrically connected in parallel with the first transformer.

4. The resistance welding apparatus according to claim 3 , wherein the polarity switching device is configured to switch the first transformer and the second transformer to the same polarity.

5. The resistance welding apparatus according to claim 1 , further comprising:
a detection device operably connected to the control device and configured to detect an electrode voltage between the first welding electrode and the second welding electrode,
wherein the control device is further configured to check a switching of the welding voltage polarity by a comparison of the detected electrode voltage with a predetermined reference electrode voltage.

6. The resistance welding apparatus according to claim 1 , wherein:
the at least one welding transformer is configured to output the at least one secondary voltage between a first output and a second output of the at least one welding transformer,
the at least one welding transformer further includes a third output;
the first transistor and the second transistor are connected between the first welding electrode and the first output;
the rectifier circuit further comprises a third transistor and a fourth transistor connected in series between the first welding electrode and the third output; and
the series connected first transistor and second transistor are in parallel with the series connected third transistor and fourth transistor.

7. The resistance welding apparatus according to claim 6 , wherein each of the first, the second, the third, and the fourth transistors are metal oxide semiconductor field effect transistors.

8. The resistance welding apparatus according to claim 1 , wherein:
the first welding electrode and the second welding electrode are included in welding tongs; and
the first welding electrode and the second welding electrode are configured to receive the at least one component therebetween during welding.

9. The installation according to claim 2 , further comprising:
at least one second line operably connecting the control device and the at least one welding transformer,
wherein the AC voltag

Assignees

• Bosch Gmbh Robert

Inventors

• Scholz Reinhard

Classifications

• B23K11/258

  the measured parameter being a voltage · CPC title

• B23K2101/006

  Vehicles · CPC title

• B23K2103/10

  Aluminium or alloys thereof · CPC title

• B23K2101/18

  Sheet panels · CPC title

• B23K11/185

  of aluminium or aluminium alloys · CPC title