Abstract: A method for manufacturing a heavy-current transformer with at least one primary winding and at least one secondary winding with surfaces for contacting connects first inner surfaces of the at least one secondary winding with an I-beam of electrically conductive material of the heavy-current transformer with a first soldering material at a first, higher melting temperature, and subsequently at least one contact plate of electrically conductive material is soldered with exterior surfaces of the at least one secondary winding with a second soldering material at a second melting temperature that is lower as compared to the first melting temperature.

Abstract: The invention relates to a heavy-current transformer (12), in particular for a power source (10) in order to provide a welding current of a resistance welding device (1), with at least one primary winding (13) and at least one secondary winding (14) with center tapping, and to a transformer element, a contact plate (29) and a secondary winding (14) for such a heavy-current transformer (12) as well as a method for the manufacturing thereof. For reduction of losses and improvement of efficiency, at least four contacts (20, 21, 22, 23) are provided to form a multi-point contacting, said contacts (20, 21, 22, 23) being formed by four contact faces within which the at least one primary winding (13) and the at least one secondary winding (14) are arranged in a series/parallel connection.

Abstract: A resistance welding device includes a power source in order to provide a welding current for welding workpieces, a welding gun with two gun arms having one electrode each in order to impress the welding current into the workpieces. The power source includes a heavy-current transformer with at least one primary winding and at least one secondary winding with center tapping, a synchronous rectifier connected with the secondary winding and including circuit elements, and a circuit for actuating the circuit elements of the synchronous rectifier. For reduction of losses and improvement of efficiency, the power source is arranged at the welding gun and the power source includes at least four contacts forming a multi-point contacting, wherein two first contacts of one polarity are connected to one gun arm and two additional contacts of opposite polarity are connected to the other gun arm.

Abstract: The invention relates to a power source (10) for providing a direct current, comprising a heavy-current transformer (12) with at least one primary winding (13) and at least one secondary winding (14) with center tapping, a synchronous rectifier (16) connected with the at least one secondary winding (14) of the heavy-current transformer (12) and comprising circuit elements (24), and a circuit (17) for actuating the circuit elements (24) of the synchronous rectifier (16), and a supply circuit (48) for supplying the synchronous rectifier (16) and the actuation circuit (17), and to a method for cooling such a power source (10). For reduction of losses and improvement of efficiency, the synchronous rectifier (16) and the actuation circuit (17) and the supply circuit (48) thereof are integrated in the heavy-current transformer (12).

Abstract: The invention relates to a synchronous rectifier (16) for integration into a power source (10) in order to provide a direct current, in particular in a cube or ashlar-shaped unit of a heavy-current transformer (12), comprising circuit elements (24), an actuation circuit (17) for actuating the circuit elements (24) and a supply circuit (48), wherein a printed circuit board (35) with conductor tracks and connection surfaces is provided for receiving electronic components.

Abstract: A heavy-current transformer, in particular for a power source in order to provide a welding current of a resistance welding device, with at least one primary winding and at least one secondary winding with center tapping, and a transformer element, a contact plate and a secondary winding for such a heavy-current transformer as well as a method for the manufacturing thereof, reduce losses and improve efficiency by providing at least four contacts to form a multi-point contacting, the contacts being formed by four contact faces within which the at least one primary winding and the at least one secondary winding are arranged in a series/parallel connection.

Abstract: The invention relates to a synchronous rectifier (16) for integration into a power source (10) in order to provide a direct current, in particular in a cube or ashlar-shaped unit of a heavy-current transformer (12), comprising circuit elements (24), an actuation circuit (17) for actuating the circuit elements (24) and a supply circuit (48), wherein a printed circuit board (35) with conductor tracks and connection surfaces is provided for receiving electronic components.

Abstract: The invention relates to a heavy-current transformer (12), in particular for a power source (10) in order to provide a welding current of a resistance welding device (1), with at least one primary winding (13) and at least one secondary winding (14) with center tapping, and to a transformer element, a contact plate (29) and a secondary winding (14) for such a heavy-current transformer (12) as well as a method for the manufacturing thereof. For reduction of losses and improvement of efficiency, at least four contacts (20, 21, 22, 23) are provided to form a multi-point contacting, said contacts (20, 21, 22, 23) being formed by four contact faces within which the at least one primary winding (13) and the at least one secondary winding (14) are arranged in a series/parallel connection.

Abstract: The invention relates to a resistance welding device (1) comprising a power source (10) in order to provide a welding current for welding workpieces (2, 3), a welding gun (4) with two gun arms (5) comprising one electrode (7) each in order to impress the welding current into the workpieces (2, 3), wherein the power source (10) comprises a heavy-current transformer (12) with at least one primary winding (13) and at least one secondary winding (14) with center tapping, a synchronous rectifier (16) connected with the at least one secondary winding (14) of the heavy-current transformer (12) and comprising circuit elements (24), and a circuit (17) for actuating the circuit elements (24) of the synchronous rectifier (16).

Abstract: The invention relates to a power source (10) for providing a direct current, comprising a heavy-current transformer (12) with at least one primary winding (13) and at least one secondary winding (14) with center tapping, a synchronous rectifier (16) connected with the at least one secondary winding (14) of the heavy-current transformer (12) and comprising circuit elements (24), and a circuit (17) for actuating the circuit elements (24) of the synchronous rectifier (16), and a supply circuit (48) for supplying the synchronous rectifier (16) and the actuation circuit (17), and to a method for cooling such a power source (10). For reduction of losses and improvement of efficiency, the synchronous rectifier (16) and the actuation circuit (17) and the supply circuit (48) thereof are integrated in the heavy-current transformer (12).