Rotary excavating down-the-hole hammer for hard rock pore-forming operation

According to the rotary excavating down-the-hole hammer for hard rock pore-forming operation, the lower portion of a power head is connected with a center rotating mechanism, the center rotating mechanism comprises a stator sleeve and a rotor sleeve, the rotor sleeve is sleeved with the stator sleeve, and the inner side and the outer side of the upper portion of the stator sleeve are provided with a first annular groove and a first radial air hole; the inner side of the stator sleeve is sequentially provided with a second annular groove, a third annular groove and a fourth annular groove from top to bottom, and is correspondingly provided with a first radial oil hole, a second radial oil hole and a third radial oil hole; an annular cavity is formed in a sleeve body of the rotor sleeve; a second radial air hole is formed in the outer side of the upper part of the rotor sleeve; a first vertical oil duct, a second vertical oil duct and a third vertical oil duct are formed in a sleeve body of the rotor sleeve; th