Abstract: In the use of U-shaped electrodes with a current supply and return in regards to the working area whereby for the stripping of insulated work pieces a heating current is applied before the welding operation, different conductor cross section requirements for the heating and welding operation present themselves. During the heating operation a cross section reduction is necessary to obtain enough heat output, but this is undesired for the welding operation. In order to solve this contradiction it is proposed to supply an electrode with a heating current supply (25a) and a return (25b), leading to the working area and returning respectively and to apply a common potential to the supply and return for the welding operation.

Abstract: In order to be able to change, without problems, the characteristic of an intended force measuring device (95, 107 through 123) provided on an electrode mounting support (7), having an electrode holder (81), according to the electrode (105) being used, the mounting support has a mounting part (75) movably fixed to a conveyor carriage (5) of a solder or welding apparatus. Thereon is guided an electrode holder (81) by a ball piston/sleeve arrangement (89, 87) and by an additional piston/cylinder arrangement (87 through 89) acting in cooperation with an exchangeable pressure spring (95) of known characteristic. An inductive displacement pickup, integrated into the second piston/cylinder arrangement, including induction coil (119, 121) is provided on the surface of the cylinder and a ferrite core (125) for cooperating therewith is mounted in the piston.

Abstract: It is proposed that the supply movement of electrodes, especially micro-welding or micro-soldering electrodes takes place in a controlled fashion. For this purpose, PRES-value receivers (65, 67) are provided, which change the PRES-value of a relatively known value for the action of the electrode with regard to the work piece, such as the geometric position, if need be additionally the supply pressure, on its output side into an electrical signal, whereby the electrode position is already detected before contacting the work piece. The working connection between positioner and a supply element (50) for the electrode (59) is therefore preferably realized by an electric motor (42), a gear wheel type threaded connecting rod (44, 46). As PRES-value receiver preferably a potentiometer (67) of known displacement/force characteristic is used which takes up a relative movement between electrode (59) and the reference system.