PERCUSSION DRILLING ASSEMBLY Russian patent published in 2006 - IPC E02F5/20 E21B7/26 

FIELD: drilling equipment, particularly self-acting drilling assemblies for ground investigation, underground service line laying and repair work performing.

SUBSTANCE: drilling assembly comprises electric drive, which rotation is transmitted to rod having thread and axial ball return channel, which connects thread ends. The rod is arranged in cup with annular inner boring in which ball is arranged. The ball provides rod connection with the cup. The cup is connected with striker, which is attached to head by spring. As rod returns in initial position ball moves upwards and entrains cup and striker, which leads to spring stretching. In upper cup position ball falls in ball return channel, cup and striker move downwards to apply impact action to head. The cup is stopped with limiter, which results in annular cup boring and ball return channel end alignment. In lower cup position ball moving along ball return channel by gravity enters into annular cup boring and in initial thread end. This results in cup engagement with the rod. Then the cycle is repeated.

EFFECT: increased operational reliability of drilling assembly used working in independent mode and reduced power inputs.

1 dwg