1998 年 16 巻 4 号 p. 421-430
The method to automatically remove the spatters which stick to the torch nozzle during GMA welding using magnetic electrode wire without touching them has been developed. By selecting the suction method with magnetic force which does not require the maintenance work of both torch and removal equipment from various nontouching method, the countermea-sures for decreasing the sticking force by spatters, removal mechanism and suitable removing force for them have been examined. In case of a carbon nozzle, the sticking force to it by spatters is less and stable for a long time. In case of a silicon nitride nozzle, the sticking force by spatters is unstable even at the initial stage and there are some cases where it increases to about 10 times of the carbon nozzle. In case of a copper nozzle, the sticking force by spatters is less at the initial stage but after its use for a long time, it becomes impossible to remove them due to the strong sticking force by their fusion. The impulse and peak value of the suction force which are necessary for success in removing the spatters in case of using the carbon nozzle become higher according as lowering the increasing speed of current. Both condenser power source and air-core coil are used for the equipment to provide the suction force and the dependability on their actual application has been confirmed.