Abstract: The invention relates to a method and an apparatus for converting the energy of an energy storage (2) for operating an arc (6), wherein a power unit (3) and an input and/or output device (5) for setting the current for operating the arc (6) is used to convert energy, as well as an appropriate welding device. In order to be able to provide the user with information on the state of energy storage (2), the time remaining for operating the arc (6) using the set current is calculated depending on a determined capacity of the energy storage (2) and a value for the current set on the input and/or output device (5), and said time is displayed on a corresponding display unit (27).

Abstract: The invention relates to a method and an apparatus for converting the energy of an energy storage (2) for operating an arc (6), wherein in order to convert energy, at least one switch (9) of a step-down converter is switched on and off in a controlled manner, wherein said at least one switch (9) is connected to the energy storage (2) at the input end. In order to be able to supply as much of the limited energy available from the energy store (2) to the arc (6), it is provided that a synchronous converter is used as the step-down converter for operating the arc (6), and that the at least one switch (9) of the synchronous converter that is designed as a power unit (3) is connected to a snubber circuit (10) at the output end such that at least the switch (9) is switched on and off in an snubbed state.

Abstract: The invention relates to a method for changing a welding process during a welding operation, wherein the change is carried out from a welding process that was conducted to a subsequent welding process during a short circuit between a melting welding wire and a workpiece, and to a method for applying heat prior to a welding operation. In order to achieve a welding process with high process stability, it is provided that, upon detecting the short circuit of the welding process that is conducted, the welding wire (9) is still moved for a defined duration (32) in the movement direction and subsequently stopped, depending on a threshold value (34) of the welding current (I) of the subsequent welding process, whereupon upon reaching the threshold value (34) of the welding current (I), the welding wire (9) is moved in the opposite direction in order to start the subsequent welding process.

Abstract: The invention relates to spot welding tongs with tong compensation, including a tong base body (4), two tong arms (6, 7) and a compensation unit (17) movably connecting one of the tong arms (6, 7) with the tong base body (4) and designed to convert a rotational movement into a linear movement, wherein the compensation unit (17) is composed of a drive unit (18) and a connector element (19), and the connector element (19) is eccentrically and movably fastened to an eccentric disc (23) fastened to the drive unit (18). In order to provide such spot welding tongs (1) with a compensation unit, which converts the rational movement into a linear movement, the connector element (19) is designed to be curved in an end region.

Abstract: The invention relates to a spot welding rod for the resistance welding of workpieces, the rod comprising a drive, which displaces the pincer arms and is configured by a spur gear and a connecting rod that is connected to the gear, the spur gear being connected to one pincer arm and the connecting rod to the other pincer arm. The invention also relates to a method for adjusting the pressure of a spot welding rod of this type. The aim of the invention is to provide a spot welding rod of this type with a simple, compact, modular construction, whose drive requires minimum maintenance and which permits a high number of spot welds. To achieve this, the connecting rod is connected to the spur gear outside the center of the latter, in particular at a defined distance to the central axis of the spur gear by means of a bearing assembly, the latter executing a curved movement during the working operation.

Abstract: A spot welding gun for resistance welding of workpieces, includes a base body and a bracket, in which electrode holders are arranged, the electrodes being in turn arranged in the holders. At least one electrode holder is fixed to an actuator that enables the electrode holder fixed thereto with the electrode to be displaced in longitudinal direction towards other electrodes. To protect the electrodes, a winding device with a band is arranged, the band being displaceably arranged between the contact surface of the electrode and the workpiece opposite the electrode. The winding device assigned to the displaceable electrode is connected to the displaceable electrode so that it moves at the same time as the electrode when the electrode is moved in longitudinal direction. The electrode holders and the electrodes have devices for guiding the band from the winding device axially along the electrode holders towards the electrode and vice versa.

Abstract: The invention relates to a method and an apparatus for converting the energy of an energy storage (2) for operating an arc (6), wherein in order to convert energy, at least one switch (9) of a step-down converter is switched on and off in a controlled manner, wherein said at least one switch (9) is connected to the energy storage (2) at the input end. In order to be able to supply as much of the limited energy available from the energy store (2) to the arc (6), it is provided that a synchronous converter is used as the step-down converter for operating the arc (6), and that the at least one switch (9) of the synchronous converter that is designed as a power unit (3) is connected to a snubber circuit (10) at the output end such that at least the switch (9) is switched on and off in an snubbed state.

Abstract: The invention relates to a method and an apparatus for converting the energy of an energy storage (2) for operating an arc (6), wherein a power unit (3) and an input and/or output device (5) for setting the current for operating the arc (6) is used to convert energy, as well as an appropriate welding device. In order to be able to provide the user with information on the state of energy storage (2), the time remaining for operating the arc (6) using the set current is calculated depending on a determined capacity of the energy storage (2) and a value for the current set on the input and/or output device (5), and said time is displayed on a corresponding display unit (27).

Abstract: Spot welding tongs for robotic applications in resistance welding of workpieces, in particular sheets, comprise tong arms, mounted such as to pivot on a base body. These tongs which may be adjusted and to which electrode holders for the electrodes are fixed and a winding device with a pay-out roller and a wind-in roller, for the winding in and out of a strip to protect at least one electrode. These spot welding tongs may be produced, in which access is not seriously affected and with a very simple and compact construction, whereby the pay-out roller and the wind-in roller of the winding device are arranged on the base body, or the tongs arm and at least one guide groove, for guiding the strip, is arranged in the tongs arm and/or the electrode holder.

Abstract: The invention relates to a method for changing a welding process during a welding operation, wherein the change is carried out from a welding process that was conducted to a subsequent welding process during a short circuit between a melting welding wire and a workpiece, and to a method for applying heat prior to a welding operation. In order to achieve a welding process with high process stability, it is provided that, upon detecting the short circuit of the welding process that is conducted, the welding wire (9) is still moved for a defined duration (32) in the movement direction and subsequently stopped, depending on a threshold value (34) of the welding current (I) of the subsequent welding process, whereupon upon reaching the threshold value (34) of the welding current (I), the welding wire (9) is moved in the opposite direction in order to start the subsequent welding process.

Abstract: The invention relates to a method for forming an end of a welding wire (13) having a defined material and a defined diameter for a threading procedure, wherein the welding wire (13) is delivered from a wire storage via at least one wire core (12) through a contact tube arranged in a welding torch (10), and to a corresponding device thereof. In order to enable automated forming of the end of a welding wire (13), according to the invention prior to the threading procedure, an electric arc (15) is generated between a contact plate (30) connected to a power source (2) and the welding wire (13) as a function of the material and the diameter of the welding wire (13) so as to form the end of the welding wire (13), wherein the end of the welding wire (13) is formed to be hemispherical and the diameter of the hemispherical end of the welding wire (13) does not substantially exceed the diameter of the welding wire (13).

Abstract: A spot welding gun for resistance welding of workpieces, includes a base body and a bracket, in which electrode holders are arranged, the electrodes being in turn arranged in the holders. At least one electrode holder is fixed to an actuator that enables the electrode holder fixed thereto with the electrode to be displaced in longitudinal direction towards other electrodes. To protect the electrodes, a winding device with a band is arranged, the band being displaceably arranged between the contact surface of the electrode and the workpiece opposite the electrode. The winding device assigned to the displaceable electrode is connected to the displaceable electrode so that it moves at the same time as the electrode when the electrode is moved in longitudinal direction. The electrode holders and the electrodes have devices for guiding the band from the winding device axially along the electrode holders towards the electrode and vice versa.

Abstract: The invention relates to a method of manufacturing a structure (1) at a surface of a work piece (4), the structure (1) standing out from the surface, wherein a welding process (7) with an at least partially fusing filler material (2) is used, wherein an arc (3) is ignited during a welding cycle (8) of the welding process (7) between the filler material (2) guided in a welding torch (5) and the work piece (4), and wherein the heat input during the welding process (7) is adjusted by controlling the welding parameters. In accordance with the invention it is provided that the structure (1) is manufactured step by step from a plurality of individual elements (6), wherein each individual element (6) is manufactured in one welding cycle (8) of the welding process (7), and wherein a welding break (9) is made after each welding cycle (8).

Abstract: A spot welding gun for resistance welding of workpieces, includes a base body and a bracket, in which electrode holders are arranged, the electrodes being in turn arranged in the holders. At least one electrode holder is fixed to an actuator that enables the electrode holder fixed thereto with the electrode to be displaced in longitudinal direction towards other electrodes. To protect the electrodes a winding device with a band is arranged, the band being displaceably arranged between the contact surface of the electrode and the workpiece opposite the electrode. The winding device assigned to the displaceable electrode is connected to the displaceable electrode so that it moves at the same time as the electrode when the electrode is moved in longitudinal direction. The electrode holders and the electrodes have devices for guiding the band from the winding device axially along the electrode holders towards the electrode and vice versa.

Abstract: There are spot welding tongs for robotic applications in resistance welding of workpieces, in particular sheets, comprising tong arms, mounted such as to pivot on a base body, which may be adjusted using an operator and to which electrode holders for the electrodes are fixed and a winding device with a pay-out roller and a wind-in roller, for the winding in and out of a strip to protect at least one electrode. According to one embodiment, such spot welding tongs may be produced, in which access is not seriously affected and with a very simple and compact construction, whereby the pay-out roller and the wind-in roller of the winding device are arranged on the base body, or the tongs arm and at least one guide groove, for guiding the strip, is arranged in the tongs arm and/or the electrode holder.

Abstract: The invention relates to a device for protecting an electrode during the resistance welding of workpieces, in particular sheet metal. Said device comprises a strip that is placed over the electrode and can be displaced in relation to the latter, a backing material of said strip having an electrically conductive coating. To improve the welding quality, the coating is applied to the opposite side of the strip from the electrode and consists of a material, whose hardness is less than that of the backing material of the strip. The soft, electrically conductive coating improves the transfer of current from the electrode to the workpiece, thus preventing weld spatter and improving the welding quality.

Abstract: A spot-welding tool having at least one electrode for resistance welding of workpieces such as metal sheets. The spot welding tool has a pressure element for holding down the workpieces arranged on the electrode in a region of the electrode cap to prevent process-dependent warping or arching of the workpiece.

Abstract: A method for resistance welding for welding two workpieces to one another using spot-welding tools. In the method, two electrodes of the spot welding tool are pressed against each other, and the electrodes are powered with energy. The workpieces are interposed and contact of the workpiece with the spot-welding tool is detected with a pressure element movably arranged on at least one of the electrodes and projecting beyond the electrode. The pressure element is then displaced relative to the electrode until the electrode contacts the workpiece.

Abstract: The invention relates to spot welding tongs with tong compensation, including a tong base body (4), two tong arms (6, 7) and a compensation unit (17) movably connecting one of the tong arms (6, 7) with the tong base body (4) and designed to convert a rotational movement into a linear movement, wherein the compensation unit (17) is composed of a drive unit (18) and a connector element (19), and the connector element (19) is eccentrically and movably fastened to an eccentric disc (23) fastened to the drive unit (18). In order to provide such spot welding tongs (1) with a compensation unit, which converts the rational movement into a linear movement, the connector element (19) is designed to be curved in an end region.

Abstract: A device for protecting an electrode during the resistance welding of workpieces, particularly of metal sheets, is made of a strip that is placed over the electrode, in a manner that enables it to be displaced in relation thereto. In order to reduce the wearing of the electrode, the strip is formed from at least two metal strips, which are arranged one atop the other and which are made of different materials. The materials of the metal strips are preferably matched to the material of the electrode and to the material of the workpiece, particularly the metal sheet, with regard to predetermined properties. A spot-welding tool is provided for carrying out the resistance welding of workpieces, particularly of metal sheets, having at least one electrode. A resistance welding method welds two workpieces, particularly metal sheets to one another by spot-welding tools.