Drill jumbo

The invention relates to the field of underground construction equipment, and discloses a drill jumbo which comprises a jumbo body, an arm frame mechanism, a drill arm unit, a first rod, a second rod and a drill bit installed at the end of the second rod. The guide head is installed at the end of the first rod, when the guide head is moved into the hole, the supporting strips on the outer wall of the guide head can support the first rod, the guide head is inserted into the hole, the outer diameter of the guide head is larger than the outer diameter of the first rod and smaller than the outer diameter of the drill bit, a polygonal sleeve groove is formed in the inner wall of the guide head, and a polygonal clamping groove is formed in one end of the first rod. Shaking caused by the fact that the first rods are matched with the second rods to extend can be reduced, and chiseled holes can be trimmed multiple times through rotation of the supporting strips; meanwhile, high-pressure water flow output by the rock d