An economical capacitor-type welding device and capacitor-type welding method that have a small power loss, that can be made compact, and that reliably control a charging circuit without being affected by the inductance of a charging path. In an exemplary capacitor-type welding device and an exemplary capacitor-type welding method of the invention, a bypass switching element having a forward-blocking function is connected in parallel to output terminals of a charging circuit, and the bypass switching element is brought into a conduction state to allow a backflow current, which is caused to flow by a magnetic energy stored in the inductance of a primary winding or an inductor included in the charging path, to bypass the charging circuit. A discharge switching element is brought into a conduction state after the bypass switching element enters the non-conduction state and recovers the forward-blocking function.

A two-piece flexplate assembly having a ring gear welded to a central plate using a capacitor discharge welding process. The weld is established between a joining structure defined between the ring gear and the central plate using either an overlap arrangement, a projection arrangement, or a chamfer arrangement.

A two-piece flexplate assembly having a ring gear welded to a central plate using a capacitor discharge welding process. The weld is established between a joining structure defined between the ring gear and the central plate using either an overlap arrangement, a projection arrangement, or a chamfer arrangement.

A direct resistance heating simulation method is provided. In this method, a welding region and its peripheral region of steel sheets to be welded by a pair of electrodes are divided into a plurality of elements. A coupled analysis is performed such that a temperature, a metal structure, stress and strain at each element are determine in a mutually associated manner based on Joule loss obtained through a current analysis and a magnetic field analysis for each element. The coupled analysis is repeated to predict an effect of one or more parameters, including at least one of a frequency, a magnitude and an application time of electric current to be applied to the electrodes, a cooling time, a pressure applied from the electrodes to the steel sheets and a shape of the electrodes, on welding quality after a post-heating by direct resistance heating and to improve weld strength.

A direct resistance heating simulation method is provided. In this method, a welding region and its peripheral region of steel sheets to be welded by a pair of electrodes are divided into a plurality of elements. A coupled analysis is performed such that a temperature, a metal structure, stress and strain at each element are determine in a mutually associated manner based on Joule loss obtained through a current analysis and a magnetic field analysis for each element. The coupled analysis is repeated to predict an effect of one or more parameters, including at least one of a frequency, a magnitude and an application time of electric current to be applied to the electrodes, a cooling time, a pressure applied from the electrodes to the steel sheets and a shape of the electrodes, on welding quality after a post-heating by direct resistance heating and to improve weld strength.

An apparatus for improving weld uniformity, controlling weld spatter and reducing weld joint bending stresses. The apparatus includes a first component having a welding contact point and a second component having a weld zone for engaging with the welding contact point of the first component. At least one weld upset distance stop is formed on the first or second component operative to control weld spatter and to reduce weld joint bending stresses.

An apparatus for improving weld uniformity, controlling weld spatter and reducing weld joint bending stresses. The apparatus includes a first component having a welding contact point and a second component having a weld zone for engaging with the welding contact point of the first component. At least one weld upset distance stop is formed on the first or second component operative to control weld spatter and to reduce weld joint bending stresses.

Apparatus and methods for fastening insulation to a metal panel are disclosed. One apparatus includes a frame; a capacitor discharge welder; a panel support bar, preferably being non-marring of a metal panel; a hopper for receiving weld pins and the weld pins; PLC controls; and a grounding clamp. Another apparatus includes a weld table, a weld pin hopper, a weld head, a welder power supply, a carriage for the weld head, a motor for moving the weld head on the carriage and a motor for moving the carriage the length of the weld table.

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.