The invention discloses a rotary
impact type rock drilling
machine and a double-layer drilling rod mechanism. The rotary
impact type rock drilling
machine comprises an excitation mechanism, a rotating mechanism and a flushing mechanism, wherein the rotating mechanism comprises a rotary box body, a driving gear, a rotary gear and a rotary
coupling sleeve; the rotary gear is tightly sheathed on the rotary
coupling sleeve and meshed with the driving gear; a
coupling link is arranged in the rotary coupling sleeve, the rotary coupling sleeve is connected with the double-layer drilling rod mechanism, an
impact drilling column which is positioned by a guide shaft
bushing is arranged in an outer-layer rotating drilling
pipe of the double-layer drilling rod mechanism, a clamping lock for connecting the coupling link is arranged at the top of the inner-layer impact drilling column, an impact head connected with the impact drilling column is arranged in a drilling bit coupling sleeve, and a drilling bit positioned below the impact head is connected with the drilling bit coupling sleeve through front coupling. As the impact head is positioned at the bottom of the double-layer drilling rod mechanism and acts on the drilling bit directly, the
impact energy generated by the rotary impact type rock drilling
machine can not be weakened along with the increase of the length of a drilling rod, the rotary impact type rock drilling machine has high efficiency of a hydraulic rock drilling machine and also has the advantages of good transfer of
impact energy and straight drilling of a downhole
drill; furthermore, the high
impact energy can be easy to generate, and large-aperture drilling and
deep hole rock drilling can be realized.