Patent ID: 8648903

Claim:
A welding tool for a spot-welding plant, including at least one retention arm for an electrode provided for resistance welding, and including a positioning unit for a tape guided past and protecting the electrode, said tape being provided for producing an image of a weld spot and increasing welding quality, with an evaluation device being arranged for analyzing the image, wherein the evaluation device comprises an optical image-detecting unit comprising: a camera comprising: at least one detection element; and one lens; and an illumination device with a diffusor for diffusively and homogeneously illuminating the image on the tape, the illumination device being configured for indirect illumination of the tape in the direction of the camera and having a light source arranged for large-area illumination of the tape, the diffusor comprising a reflector having a reflector surface, the reflector, at the reflection surface, reflecting the light beams generated by the light source in the direction of the tape.