Core Drilling Tools With Retractably Lockable Driven Latch Mechanisms

A drilling system for retrieving a core sample, comprising:

• a drill string having a longitudinal axis, an inner surface, a landing ring, and a plurality of drill rods, the inner surface of the drill string defining an annular groove;
• a core barrel head assembly having a landing portion and a sleeve defining a plurality of openings, the core barrel assembly being adapted to be inserted within the drill string, wherein the landing portion defines a landing shoulder configured for frictional engagement with the landing ring of the drill string,
• a driven latch mechanism positioned within the core barrel assembly, wherein the driven latch mechanism comprises a driving member, a plurality of wedge members, and a biasing member configured apply a biasing force to bias the driving member against the plurality of wedge members, the plurality of wedge members being positioned on the driving member and unattached to the core barrel assembly, the driving member having an outer surface defining a plurality of driving surfaces spaced circumferentially about the outer surface, the driving member comprising at least one first groove extending therein, the at least one first groove being configured to receive and maintain the plurality of wedge members in a retracted position, wherein, within the at least one first groove, the plurality of wedge members are retained in the retracted position by a retention force;
• wherein, during the frictional engagement between the landing shoulder and the landing ring of the outer tube, the core barrel head assembly is configured to rotate with the drill string, and wherein the rotation of the drill string is configured to produce a centrifugal force that overcomes the retention force, thereby causing the wedge members to extend radially outward of the sleeve into the annular groove in the inner surface of the drill string.

A method of drilling using a core barrel assembly comprising a sleeve, a driving member, and a plurality of wedge members, comprising:

• manipulating the core barrel assembly to position the plurality of wedge members into at least one retracted groove on the driving member, the driving member having an outer surface defining a plurality of driving surfaces spaced circumferentially about the outer surface, the driving member being positioned at least partially within the sleeve, the plurality of wedge members being unattached to the core barrel assembly, the driving member defining a plurality of driving surfaces, the at least one retracted groove being configured to receive and maintain the plurality of wedge members in a retracted position within the sleeve, wherein, within the at least one retracted groove, the plurality of wedge members are retained in the retracted position by a retention force;
• inserting the core barrel assembly within a drill string, the drill string having a longitudinal axis and an inner surface, the inner surface of the drill string defining an annular groove;
• moving the core barrel assembly within the drill string to a drilling position, wherein, in the drilling position, a landing shoulder of the core barrel assembly frictionally engages a landing ring of a drill string, wherein during the frictional engagement between the landing shoulder and the landing ring, the core barrel assembly is configured to rotate with the drill string;
• and
• rotating the drill string to produce a centrifugal force that overcomes the retention force, thereby causing the wedge members to extend radially outward of the sleeve into the annular groove in the inner surface of the drill string.