Hydro-percussive mechanisms for drilling systems

A wire-line core barrel assembly, comprising:

• an outer tube having a lower core barrel;
• a hydro-percussive mechanism configured to be positioned within the outer tube and to transmit a percussive force to the lower core barrel, the hydro-percussive mechanism including:
• a housing assembly having a head end and a bit end;
• the housing assembly further including an inlet joint having an inlet channel defined therein, a sealing portion positioned toward the bit end relative to the inlet joint, and a outlet portion positioned toward the bit end relative to the sealing portion;
• a hammer assembly having a hammer and a piston, the piston having a piston channel defined therein the piston channel having an inlet in fluid communication with the inlet channel and an outlet in fluid communication with the housing assembly;
• an anvil assembly including an anvil;
• and
• a biasing member positioned at least partially between the hammer and the anvil, the biasing member biasing the hammer away from the anvil to urge the hammer assembly toward the head end to position the outlet in the piston in communication with the sealing portion of the housing assembly;
• wherein the translation of the hammer assembly toward the anvil assembly moves the outlet in the piston into communication with the outlet portion of the housing assembly.

A drilling system, comprising:

• an outer tube having a lower core barrel;
• a hydro-percussive mechanism configured to be positioned within the outer tube and to transmit a percussive force to the lower core barrel, the hydro-percussive mechanism including:
• a housing assembly having a head end and a bit end;
• the housing assembly further including inlet channel, a sealing portion positioned toward the bit end relative to the inlet joint, and a outlet portion positioned toward the bit end relative to the sealing portion;
• a hammer assembly having a hammer and a piston, the piston having a piston channel defined therein the piston channel having an inlet in fluid communication with the inlet channel and an outlet in fluid communication with the housing assembly;
• and
• an anvil assembly including an anvil and an anvil channel extending through the anvil;
• wherein translation of the hammer toward the anvil moves the outlet in the piston into communication with the outlet portion of the housing assembly such that fluid can flow from the inlet channel to the anvil channel, and through the anvil to the lower core barrel.

A method of drilling, comprising:

• positioning an outer tube within a formation, the outer tube including a drill bit secured to a distal end thereof;
• inserting a down-the-hole assembly within the outer tube;
• latching the down-the-hole assembly to the outer tube;
• rotating and driving the drill bit into the formation;
• and
• directing pressurized fluid to a piston to generate a pressure force due to engagement between outlets in the piston and sealing portion of a housing assembly of the down-the-hole assembly thereby causing a hammer of the down-the-hole assembly to advance against an anvil of the down-the-hole assembly thereby applying a percussive force to the drill bit;
• reducing the pressure force once the hammer is moved toward the anvil by directing pressurized fluid out of the piston through engagement between the outlets in the piston and an outlet portion of the housing assembly, to the anvil, through an anvil channel in the anvil, and beyond the anvil to the drill bit;
• and
• moving the hammer assembly to position the outlets in the piston into engagement with the sealing portion of the housing assembly once the pressure force is reduced.