PNEUMOSTRIKER Russian patent published in 2006 - IPC E21B4/14 

FIELD: percussion mechanisms, particularly pneumostrikers used for well drilling during open cast mining.

SUBSTANCE: pneumostriker comprises cylinder, adapter, head with drilling bit secured in the head, spring-loaded piston with shank and central channel having widened part and striking part. Borings arranged in three layers are created in central channel of the widened piston part. Slide is installed in the central channel. Piston shank may be inserted in central orifice of the adapter. The slide is tubular and provided with solid partition and side windows arranged from both partition sides. The slide is pressed to stops installed in central piston channel with spring secured between the slide and inner ledge created in area of central piston channel reduction. Bush with flange resting upon slide end facing the head is located inside slide spring. The bush is installed so that bush neck may pass in central channel of striking piston part and in axial bit channel. Bush installed in the spring creates cavity in central piston channel. The cavity is communicated with piston underside by radial orifices.

EFFECT: increased operational efficiency due to improved energy carrier distribution unit.

1 dwg