Abstract: An automatic bonding apparatus and a method for thermally induced seam bonding of weldable and/or gluable flat flexible material layers with each other which are each configured as a material web, material band and/or material piece and arranged so that they overlap at least partially wherein the bonding is performed by an electrically controlled contact heating arrangement through a heating wedge welding method. A temperature and/or a power of the heating wedge which is formed by a thin folded steel sheet blank is controlled as a function of a relative velocity between the material layers and the automatic bonding apparatus. This is performed so that a thermal energy that is transferred from the heating wedge to the material layers to be glued is kept constant. For this purpose the relative velocity is detected and the power of the heating wedge is automatically adjusted when the relative velocity changes.