Carbon dioxide gas shielded welding device

The invention discloses a carbon dioxide gas shielded welding device which comprises a rail (1), wherein a trolley (2) is arranged on the rail (1) and connected with a case (18); a fixed block (3) is arranged on the trolley (2); a gear (5) is arranged on the fixed block (3) and connected with a motor (6); a rack (4) engaged with the gear (5) is connected with a transverse stop block (7); the transverse stop block (7) is connected with a gun head (8) via a bolt; the gun head (8) is connected with a welding machine (17); fine adjustment mechanisms (9) are arranged on the two sides of the tail end of the gun head (8) and arranged on a movable plate (10); the movable plate (10) is connected with air cylinders (11); the fine adjustment mechanisms (9) comprise rotary buttons (13); the rotary buttons (13) are connected with worms (12); the worms (12) are connected with push rods (14); and the push rods (14) are connected with pressing blocks (15). The device is convenient to move, reduces labor intensity and has goo