The invention discloses a
welding device for a three-gear and four-gear shifting fork shaft. The
welding device comprises a sealed
welding box, a shaft lever feed device, a gear shifting guide block feed device, a vacuumizing device, a controller and a
drive motor, wherein a welding die, an
arc welding machine and a moving mechanism used for controlling the
arc welding machine to move are arranged in the welding box, the shaft lever feed device and the gear shifting guide block feed device are communicated with the welding box, the vacuumizing device and the controller are arranged on the welding box, an observation window is arranged on the operating face of the welding box, rolling curtain cloth is arranged above the observation window, and two operation gloves are arranged below the observation window. The
drive motor is used for driving the rolling curtain cloth to be rolled down to seal the observation window before welding and to be rolled up after welding, and electrically connected with the controller. The welding device has the advantages that an operator places a shaft lever and a gear shifting guide block to the designed positions on the welding die by means of the operation gloves, then the controller controls the
drive motor to roll the rolling curtain cloth down to seal the observation window, under the vacuum condition, the connecting portion of the shaft lever and the gear shifting guide block is welded, the situation that the high-temperature part of the shaft lever is oxidized in the
welding process is avoided, and injuries to eyesight of the operator in the
welding process can be prevented.