DOWNHOLE AIR-DRIVEN HAMMER Russian patent published in 2013 - IPC E21B4/14 

FIELD: machine building.

SUBSTANCE: proposed device comprises drill bit with central blow channel, hollow body with release channels, striker dividing body inner space into chambers of working and return strokes, adapter with the main pressure channel and counterbore secured in hollow body, and distribution system including seat with channels and central bore made in hollow body top part. Tube with pressure channels and central blow bore is fitted therein and communicated with central blow bore of drill bit. It includes also the box with release and feed channels arranged at said seat. Stepped valve is arranged between said seat and box to make release chamber by its inner surface and said box. It comprises circular chamber formed between said box and stepped valve outer surface to communicate via box feed holes with the adapter main pressure channel. Nozzle with central channel converging along power carrier flow is arranged in adapter counterbore and in seat central bore. Nozzle wall has openings to communicate the adapter main pressure channel via box feed openings with said distribution system circular chamber.

EFFECT: higher efficiency and reliability.

2 cl, 2 dwg