Hydro-pneumatic counterblow hammer

The utility model belongs to a hydro-pneumatic counterblow hammer. A lower hammerhead is arranged on a lower supporting piston of a hydraulic cylinder, a secondary cylinder bottom on the lower end of a secondary cylinder piston is communicated with the hydraulic cylinder, the upper end of the secondary cylinder piston is arranged outside the top end of the secondary cylinder and connected with a side end of the upper hammerhead, and the upper portion of the upper hammerhead is connected with the lower end of a primary cylinder piston which is positioned in a primary cylinder through a hammer rod. The hydro-pneumatic counterblow hammer has two paths of oil supply systems, one oil supply system supplies general high-pressure oil to the hydraulic cylinder, and the other oil supply system supplies oil to an accumulator and oil entering the primary cylinder through a primary operating valve and a quick release valve. An air supply system of the hydro-pneumatic counterblow hammer supplies nitrogen to the accumulato