A capacitive discharge welding system includes at least one capacitive discharge-based power supply that is adapted to provide alternate polarity pulses from a first weld to a subsequent weld, and to be compatible with iron-core transformers used for alternating current resistance welding; at least one iron core transformer adapted to receive electrical discharges from the capacitive discharge-based power supply; a polarity switching network that includes at least two sets of silicon controlled rectifiers that are arranged in pairs for facilitating current flow in alternate directions; a pair of engagable, properly biased shunt diodes that are operative to shunt reflected current for protecting the silicon controlled rectifiers when the system is in use; and a control network configured for simultaneous engagement of the properly biased shunt diodes and firing the silicon controlled rectifiers for current flow; and tracking polarity for assuring that subsequent pulses use opposite direction current flow for preventing saturation of the iron core transformer.

A capacitive discharge welding system includes at least one capacitive discharge-based power supply that is adapted to provide alternate polarity pulses from a first weld to a subsequent weld, and to be compatible with iron-core transformers used for alternating current resistance welding; at least one iron core transformer adapted to receive electrical discharges from the capacitive discharge-based power supply; a polarity switching network that includes at least two sets of silicon controlled rectifiers that are arranged in pairs for facilitating current flow in alternate directions; a pair of engagable, properly biased shunt diodes that are operative to shunt reflected current for protecting the silicon controlled rectifiers when the system is in use; and a control network configured for simultaneous engagement of the properly biased shunt diodes and firing the silicon controlled rectifiers for current flow; and tracking polarity for assuring that subsequent pulses use opposite direction current flow for preventing saturation of the iron core transformer.

A welding machine for welding together the tail of a billet to the head of a second billet along a feeding direction, the machine comprising a carriage adapted to slide along the feeding direction, said carriage supporting a first structure integrally fixed to said carriage; first clamping means, provided on said first structure, for clamping the head of the second billet; a second structure connected to the first structure and sliding, parallel to the feeding direction, with respect to both the first structure and the carriage; second clamping means, provided on said second structure, for clamping the tail of the first billet; wherein first adjustment means are provided for adjusting the position of the second structure with respect to the first structure along said feeding direction; and second adjustment means are provided for adjusting the position of the second structure with respect to the first structure on a plane transversal to the feeding direction, so as to align the second clamping means with the first clamping means along said feeding direction.

An electric resistance spot welding device, comprising a pair of electrodes located on the same welding surface of an assembly to be welded. The assembly to be welded is provided with an axis of symmetry (6); the pair of electrodes are symmetrically disposed on two sides of the axis of symmetry; one end of each electrode has a special-shaped contact surface (20); the special-shaped contact surfaces are respectively offset in directions away from the axis of symmetry relative to the electrode axis, wherein the special-shaped contact surfaces are used for offsetting a current density centerline (21) formed by the electrodes in a direction away from the axis of symmetry relative to the electrode axis (11), and/or used for deflecting the tendency of the current density of each electrode away from a welding face within the assembly to be welded. The device can achieve a symmetrical and uniform shape of distal and proximal ends of a nugget with respect to the axis of symmetry, such that both the shape and stress state of the nugget can meet requirements for mechanical properties under load, thus improving the welding quality. The present application also relates to an electric resistance spot welding method.

An electric resistance spot welding device, comprising a pair of electrodes located on the same welding surface of an assembly to be welded. The assembly to be welded is provided with an axis of symmetry (6); the pair of electrodes are symmetrically disposed on two sides of the axis of symmetry; one end of each electrode has a special-shaped contact surface (20); the special-shaped contact surfaces are respectively offset in directions away from the axis of symmetry relative to the electrode axis, wherein the special-shaped contact surfaces are used for offsetting a current density centerline (21) formed by the electrodes in a direction away from the axis of symmetry relative to the electrode axis (11), and/or used for deflecting the tendency of the current density of each electrode away from a welding face within the assembly to be welded. The device can achieve a symmetrical and uniform shape of distal and proximal ends of a nugget with respect to the axis of symmetry, such that both the shape and stress state of the nugget can meet requirements for mechanical properties under load, thus improving the welding quality. The present application also relates to an electric resistance spot welding method.

A projection portion is formed on a distal end surface of a supply rod with which a surface of a flange is to be brought into close contact. A circular-arc receiving surface fitting an outer peripheral portion is formed at a boundary portion between the distal end surface and the projection portion. One side of the circular-arc receiving surface is continuous with the distal end surface, and another side of the circular-arc receiving surface is continuous with a regulation inner surface formed on the projection portion in a state of being opposed to the distal end surface. With this, a receiving groove is formed, and a control gap is defined between the regulation inner surface and the flange. The close contact of the surface with the distal end surface is achieved with a magnet of an advancing/retreating type provided in the supply rod.

An electrode is provided for the resistance welding of bolts, having an upper part and a lower part which are configured to be connectable together and, in the connected state, jointly provide a cavity, the upper part having an opening for introducing a bolt, and the lower part having a gas connection for a pressurized gas. A valve body, by way of which the opening is closable, is arranged in the cavity. As a result, applied compressed air is prevented from flowing out. Compressed air only emerges when the valve body opens up the opening.

An electrode is provided for the resistance welding of bolts, having an upper part and a lower part which are configured to be connectable together and, in the connected state, jointly provide a cavity, the upper part having an opening for introducing a bolt, and the lower part having a gas connection for a pressurized gas. A valve body, by way of which the opening is closable, is arranged in the cavity. As a result, applied compressed air is prevented from flowing out. Compressed air only emerges when the valve body opens up the opening.

Heating element for user-touchable areas in a vehicle with a foamed carrier material in which at least one heating conductor, which comprises an electrical insulation, is embedded, and with connecting conductors which are electrically connected to the ends of the heating conductor via at least one connection part and form an electrical feed line. The at least one connection part is arranged within the foamed carrier material and the connection part is foam-covered in an electrically insulating manner by the carrier material. The connection part is brought into electrically conductive contact at least partially with the respective connection end of the heating conductor due to applied pressure and/or applied heat, at least partially destroying the electrical insulation in the region of the connection part. Furthermore, a method for producing such a heating element using a mold tool is indicated.

A method for joining an electrical terminal pre-populated in a contact carrier and an electrical conductor includes arranging a connection portion of the electrical conductor at a receiving section of the electrical terminal pre-populated in the contact carrier, arranging at least two electrodes on one or more sides of the receiving section of the electrical terminal pre-populated in the contact carrier receiving the connection portion of the electrical conductor, and fusing the connection portion of the electrical conductor and the receiving section of the electrical terminal pre-populated in the contact carrier by using the electrodes to join the electrical conductor and the electrical terminal pre-populated in the contact carrier.