Patent EP-2008750-B1 (EP)
Inventor: FUESSEL UWE PROF DR-ING HABIL
IPC: B23K9/167
Filed: 2008-06-26
Granted: 2010-11-24
Abstract: The tungsten inert gas welding torch with a torch head (30) for welding workpieces, comprises a housing cylinder (31) with an upper cover clasp (32) through which a flow line and a return line (34) for coolant and/or a process gas line (35) and an electro connection for processing a tungsten electrode are guided, an elongated cool body (37) present within the housing cylinder, a cavity, which opens at the upper forehead side of the cool body, an interior cover clasp present on the cool body, and a countersunk tapped hole admitted on the lower forehead side of the cool body. The tungsten inert gas welding torch with a torch head (30) for welding workpieces, comprises a housing cylinder (31) with an upper cover clasp (32) through which a flow line and a return line (34) for coolant and/or a process gas line (35) and an electro connection for processing a tungsten electrode are guided, an elongated cool body (37) present within the housing cylinder, a cavity, which opens at the upper forehead side of the cool body, an interior cover clasp present on the cool body, a countersunk tapped hole admitted on the lower forehead side of the cool body along the torch head axis, a lockable electrode passing in the tapped hole, and a screwable gas nozzle in connection with the cool body under bonding of longitudinal channels. The flow line for the coolant guides by the interior cover clasp. The electrode has a cylindrical tungsten electrode body (81) equipped with a cone tip. The tip end of the electrode body is arranged in a given interval to the lower forehead side of the cool body. The thermal resistance of the materials subordinated to the electrode body is low. The cooling is carried out over the cool body up to the tapped hole or directly to the electrode and forms an emission isotherm that is transferred through the intensive cooling of the electrode, the electrode diameter and through a defined angle towards to the free tip end. The electro connection for operating the tungsten electrode is mounted at the return line direction. The lockable electrode has a fiber adapted to the tapped hole at the cylindrical part of the electrode body and is directly screwed in the tapped hole. The electrode has electrode holder having a passage in which the tungsten electrode body is secured by soldering or press-in-operation. The electrode holder possesses an external fiber adapted to the tapped hole for screwing in the tapped hole. The electrode holder is formed as a hollow screw. The tungsten electrode body is jointly interchangeable in the fall of a characteristic fiber even interchangeable or in the fall of binding in the electrode holder actuated by outside of the torch head with the electrode holder. The electrode holder consists of a material with low thermal resistance. The cylindrical parts of the electrode body and the electrode holder are connected in positive or non-positive manner. A slight electrical and thermal resistance is intended between the electrode body and the electrode holder. The cooling is carried out within the cool body as a fluid cooling. The longitudinal channels are arranged between the cool body and the gas nozzle in axial direction to torch head axis and are subjected on the external wall of the cool body and/or also on the internal wall of the gas nozzle. The tip end of the tungsten electrode body has a slight interval for the coolant cool body. The opening angle of the conical electrode tip is 7-90[deg] .