A multi-loop antenna and an RFID system are used for monitoring tools when machining rotationally symmetric workpieces. A multi-loop antenna is arranged on a tool carrier near a rotationally symmetric tool so that multi-loop antenna encloses the rotationally symmetric tool and the rotationally symmetric tool carries an RFID transponder. The position of this RFID transponder is arranged on the rotationally symmetric tool so that it is arranged in the electromagnetic ring field of the multi-loop antenna. The multi-loop antenna is arranged on the tool carrier so that it is possible to query the RFID transponder on the rotationally symmetric tool in any position while in motion and when at rest.

A welding tip inspection apparatus and method to mom accurately inspect dressing quality and a foreign object attachment regarding a front end of a welding tip using a color sensing technique is provided. The welding tip inspection apparatus includes an inspection block on which a front end of a welding tip is mounted, a color sensor that is disposed within the inspection block, that is configured to irradiate light to the front end of the welding tip and that is configured to receive the reflected light from the front end of the welding tip. A controller is configured to analyze a wavelength of each color of the reflected light received by the color sensor.

A method of resistance spot welding workpiece stack-ups of different combinations of metal workpieces with a single weld gun using the same set of welding electrodes is disclosed. In this method, a set of opposed welding electrodes that include an original shape and oxide-disrupting structural features are used to resistance spot weld at least two of the following types of workpiece stack-ups in a particular sequence: (1) a workpiece stack-up of two or more aluminum workpieces; (2) a workpiece stack-up that includes an aluminum workpiece and an adjacent steel workpiece; and (3) a workpiece stack-up of two or more steel workpieces. The spot welding sequence calls for completing all of the aluminum-to-aluminum spot welds and/or all of the steel-to-steel spot welds last.

A series of many electrical resistance spot welds is to be formed in members of an assembled, but un-joined, body that presents workpiece stack-ups of various combinations of metal workpieces including all aluminum workpieces, all steel workpieces, and a combination of aluminum and steel workpieces. A pair of spot welding electrodes, each with a specified weld face that includes oxide-disrupting features, is used to form the required numbers of aluminum-to-aluminum spot welds, aluminum-to-steel spot welds, and steel-to-steel spot welds. A predetermined sequence of forming the various spot welds may be specified for extending the number of spot welds that can be made before the weld faces must be restored. And, during at least one of the aluminum-to-steel spot welds, a cover is inserted between the weld face of one of the welding electrodes and a side of a workpiece stack-up that includes the adjacent aluminum and steel workpieces.

A moving mechanism brings the rotational axis of each driven rotator into alignment with the rotational axis of a drive rotator, which has an engaging face extending along its rotational axis. Each driven rotator has an engageable face extending along the rotational axis of the drive rotator. Rotating the drive rotator while moving the driven rotator, of which the rotational axis is aligned with the rotational axis, toward the drive rotator will bring the engaging face into engagement with the engageable face.

To accurately make a dressing quality determination based on resistance waveforms, a dressing quality determination method determines the quality of dressing performed for electrodes when resistance welding is performed at a plurality of welding points. This method includes accumulating a known resistance waveform immediately after dressing the electrodes, and a known resistance waveform immediately before dressing the electrodes; creating, by a statistical method, a model for setting a threshold value for dressing quality determination, based on a plurality of known resistance waveforms immediately after dressing and a plurality of known resistance waveforms immediately before dressing; acquiring an unknown resistance waveform immediately after dressing the electrodes; and determining whether dressing is normal or dressing is abnormal by comparing the unknown resistance waveform immediately after dressing with the threshold value for dressing quality determination.

A method for operating a welding device for resistance welding includes carrying out a verification measurement by moving electrodes of the welding device toward one another and measuring a force in combination with measuring a distance between the electrodes. Electrode wear is ascertained by using the measured distance. The electrodes or component parts of the electrodes are changed or cleaned depending on the ascertained electrode wear.

A cutting tool that can simultaneously cut and restore asymmetric weld face geometries of two welding electrodes that are subject to different degradation mechanisms is disclosed along with a method of using such a cutting tool during resistance spot welding of workpiece stack-ups that include dissimilar metal workpieces. The cutting tool includes a first cutting socket and a second cutting socket. The first cutting socket is defined by one or more first shearing surfaces and the second cutting is defined by one or more second shearing surfaces. The first shearing surface(s) and the second shearing surface(s) are profiled to cut and restore a first weld face geometry and a second weld face geometry, respectively, that are different from each other upon receipt of electrode weld faces within the cutting sockets and rotation of the cutting tool.

A cutting tool that can simultaneously cut and restore asymmetric weld face geometries of two welding electrodes that are subject to different degradation mechanisms is disclosed along with a method of using such a cutting tool during resistance spot welding of workpiece stack-ups that include dissimilar metal workpieces. The cutting tool includes a first cutting socket and a second cutting socket. The first cutting socket is defined by one or more first shearing surfaces and the second cutting is defined by one or more second shearing surfaces. The first shearing surface(s) and the second shearing surface(s) are profiled to cut and restore a first weld face geometry and a second weld face geometry, respectively, that are different from each other upon receipt of electrode weld faces within the cutting sockets and rotation of the cutting tool.

A low-cost tip dressing cutter causing no accumulation of swarf around a breaker is provided. A surface of a breaker 5 facing a cutting plate 4 corresponds to a recessed surface 52. The diameter of the recessed surface 52 gradually decreases with increasing distance from the outer periphery of the recessed surface 52 facing the cutting plate 4 in a direction opposite to the cutting plate 4. A through hole 51 is formed at the center of the breaker 5, A screw 6 inserted through the through hole 51 is screwed to a fastening hole 33a of a holder 3 to attach the cutting plate 4 to the breaker 5.