Method and device for joining moulded parts by electromagnetic welding

A device for joining moulded parts by electromagnetic welding, comprising:

• means for moving a joining inductor along a welding path of contact surfaces of the moulded parts,
• means for generating an electromagnetic field in an induction-sensitive component of the moulded part(s) to heat a thermally activated coupling material of the moulded part(s) to above a melting temperature of the coupling material, and
• means for joining the moulded parts to each other in the contact surfaces by the molten coupling material,
• a sensing inductor configured for determining the strength of the electromagnetic field suitable for joining along the welding path, the sensing inductor further including an emitting inductor for generating a relatively weak electromagnetic field to slightly heat the thermally activated coupling material to a sensing temperature, and a receiving inductor for measuring the field strength generated by the emitting inductor in the moulded part(s),
• the sensing inductor configured for determining a discrepancy between the measured field strength of the receiving inductor and the field strength suitable for joining for each position along the welding path, and
• the sensing inductor further configured for adjusting the field strength suitable for joining to close the discrepancy by adapting a power or a voltage supplied to the joining inductor for each of said positions along the welding path.