Overshot tool having latch control means

摘要

An overshot tool for releasable connection to a head assembly as part of a core barrel drilling apparatus. The overshot tool comprises a primary engaging portion and a secondary engaging portion and is configured for the automated coupling and decoupling to a head assembly via selected engagement of the head assembly by the engaging portion. The overshot tool is configured to both deliver and retrieve a head assembly from a latched position at a cutting end the core barrel.