CUTTING UNIT OF HYDROMECHANIC SLOT-TYPE PERFORATOR Russian patent published in 2012 - IPC E21B43/112 

FIELD: mining.

SUBSTANCE: cutting unit performed in perforator casing and actuated by piston or plunger brings into action extending cutting tools located on holders, one of which is fixed in relation to piston (plunger), and the other - in relation to perforator casing. The holders are performed with the possibility of interaction and movement in relation to each other with extension of cutting tools to opposite directions at piston (plunger) movement. Cutting unit is additionally equipped with mechanism that brings the extending parts into transport position and fixes them in this position; the mechanism includes at least one guiding slot that is done in the holder fixed in relation to the casing and at least one rod attached to the holder fixed in relation to the piston (plunger) or at the piston (plunger) capable of moving along the slot and thus providing the return of holder with slot into transport position at piston (plunger) reverse movement and including the groove made in the holder fixed in relation to the piston (plunger) in form close to casing edge with the possibility of fixing this holder in the casing without any pressure on the piston (plunger) due to casing edge contact with holder groove.

EFFECT: increase of perforator reliability and safety, improvement of its performance characteristics.

5 cl, 1 dwg