QUICK RELEASE DOWN-THE-HOLE HAMMER DRILL BIT ASSEMBLY Russian patent published in 2018 - IPC E21B17/04 

FIELD: soil or rock drilling; mining.

SUBSTANCE: group of inventions relates to a down-the-hole hammer drill bit assembly and to a drilling device for percussion-rotary drilling of rock. Down-the-hole hammer drill bit assembly comprises a drill bit, an elongated body for creating a piston housing, an annular drive sub, a retaining sleeve. Drill bit has a rock-breaking head and a shank. Radially outwardly facing portion of the shank comprises first retaining connections. Annular drive sub is located on the axially forward end of the body. Shank is located in the drive sub and runs axially through it. Radially outward-facing portion of the drive sub comprises second retaining connections. Retaining sleeve has a first end mounted over the shank portion and a second end mounted over the drive sub portion. Retaining sleeve comprises third and fourth retaining connections on the radially inward-facing portion to engage with the first and second retaining connections, respectively, to axially connect the drill bit to the drive sub. First and third connections can be axially disengaged from each other and provide axial disengagement of the drill bit from the sleeve by axially moving the drill bit forward relative to the drive sub. Second and fourth connections can be axially disengaged from each other and provide axial disengagement of the sleeve from the drive sub by axially moving the sleeve forward relative to the drive sub. Axial connection of the drill bit to the drive sub is created exclusively by engagement between the respective first and third retaining connections, as well as the second and fourth retaining connections.

EFFECT: technical result consists in a easier and faster replacement of the drill bit.

14 cl, 13 dwg