Patent ID: 8604378
Filing Date: 2013-12-10
Classification: B23K

Abstract:
1. An electrode unit used in a resistance welder having a pair of positive and negative electrodes, the resistance welder pressing and energizing a workpiece by the electrodes to weld the workpiece, the electrode unit comprising: a case interposed between one of the electrodes and the workpiece; a plurality of electrode pins provided in the case, the plurality of electrode pins being independently movable toward and away from the workpiece to be in contact with the workpiece for applying an electric current to the workpiece; a welding pressure adjusting mechanism that independently adjusts a welding pressure applied on each of the electrode pins toward the workpiece; and a protrusion adjusting mechanism that independently adjusts a protrusion of each of the electrode pins toward the workpiece, wherein the electrode pin is provided with a contact end touching the workpiece and a head opposite to the contact end, the head having a slit, the case has an opening in which the electrode pin is axially slidable and a slitted opening extending in a radial direction of the head is provided on an inner wall of the opening, and a metal elastic body having a bent or curved shape is provided in the slit and the slitted opening, the metal elastic body pressing the head of the electrode pin toward the inner wall.