Drilling mechanism capable of automatically lengthening or disassembling drill rod

The utility model discloses a drilling mechanism capable of automatically lengthening or disassembling a drill rod, which relates to the field of tunnel construction equipment, and comprises a propelling beam, a fixed drill rod clamping device and a plurality of rod feeding manipulators, and a rock drill is slidably arranged on the propelling beam; the fixed drill rod clamping device is fixedly installed on the propelling beam and comprises two chucks which are symmetrically arranged and can be close to each other, a clamping area is formed between the two chucks, and the output end of the rock drill is arranged right opposite to the clamping area; the multiple rod feeding mechanical arms are arranged on one side of the propelling beam in a linear mode, each rod feeding mechanical arm comprises a swing arm, a swing hydraulic cylinder, a fixed chuck, a movable chuck and a clamping hydraulic cylinder, and the clamping hydraulic cylinders can drive the movable chucks to be close to the fixed chucks so as to clam