Driven latch mechanism
View Patent ↗A core barrel assembly having a driven latch mechanism that can lock the core barrel assembly axially and rotationally relative to a drill string. The driven latch mechanism can include a plurality of wedge members positioned on a plurality of driving surfaces. Rotation of the drill string can cause the plurality of wedge members to wedge between an inner diameter of the drill string and the plurality of driving surfaces, thereby rotationally locking the core barrel assembly relative to the drill string. Drilling systems including the driven latch mechanism and methods of using the driven latch mechanism are also described.
1. A core barrel head assembly having a longitudinal axis and configured to be removably received within a drill string, comprising:
a sleeve having a plurality of latch openings extending there through;
a driving member positioned at least partially within the sleeve, the driving member having an outer surface defining a plurality of discrete driving surfaces that are spaced circumferentially about the outer surface of a distal end of the driving member and that are distally tapered relative to the longitudinal axis of the core barrel head assembly, wherein, in cross-section of the driving member, each portion of each driving surface of the plurality of discrete driving surfaces has a radius relative to the longitudinal axis of the core barrel head assembly, and wherein the radius of at least a portion of each driving surface varies across the cross-sectional width of each driving surface; and
a plurality of wedge members, each wedge member of the plurality of wedge members being positioned on a portion of a respective driving surface of the plurality of driving surfaces, the plurality of wedge members extending within the plurality of latch openings about and between a released position and a locked position;
wherein each wedge member of the plurality of wedge members is unattached to other portions of the core barrel head assembly, and
wherein, when the plurality of wedge members are positioned in the locked position, the driving member is configured to wedge the plurality of wedge members between portions of the inner surface of the drill string and respective portions of the plurality of driving surfaces to axially and rotationally lock the core barrel head assembly relative to the drill string.
2. The core barrel head assembly as recited in claim 1 , wherein the driving surfaces of the plurality of driving surfaces are planar.
3. The core barrel head assembly as recited in claim 1 , wherein the wedge members of the plurality of wedge members are generally spherical.
4. The core barrel head assembly as recited in claim 1 , wherein each respective driving surface of the plurality of driving surfaces has a minimal spacing from the longitudinal axis of the core barrel head assembly at the distal end of the driving member.
5. The core barrel head assembly as recited in claim 4 , wherein axial translation of the driving member results in radial displacement of the plurality of wedge members between the released position and the locked position.
6. The core barrel head assembly as recited in claim 1 , further comprising:
a valve positioned within the sleeve; and
a ball piston configured to engage the valve and prevent fluid from passing through the sleeve past the valve.
7. The core barrel head assembly as recited in claim 1 , further comprising a biasing member configured to bias the driving member against the plurality of wedge members.
8. The core barrel head assembly as recited in claim 7 , wherein the biasing member is positioned within the driving member.
9. The core barrel head assembly as recited in claim 1 , further comprising a braking mechanism, the braking mechanism comprising a landing member and a plurality of braking elements.
10. The core barrel head assembly as recited in claim 9 , wherein the braking elements of the plurality of braking elements are generally spherical.
11. The core barrel assembly as recited in claim 10 , wherein axial translation of the landing member results in radial displacement of the plurality of braking elements between a retracted position and an extended position.
12. The core barrel head assembly as recited in claim 1 , wherein at least a portion of each driving surface of the plurality of discrete driving surfaces is non-planar.
13. A core barrel head assembly having a longitudinal axis and configured to be removably received within a drill string, comprising:
a sleeve having a plurality of latch openings extending there through;
a driving member positioned at least partially within the sleeve, the driving member having an outer surface defining a plurality of discrete planar driving surfaces that are spaced circumferentially about the outer surface of a distal end of the driving member and that are distally tapered relative to the longitudinal axis of the core barrel head assembly; and
a plurality of generally spherical wedge members, each wedge member of the plurality of wedge members being positioned on a portion of a respective driving surface of the plurality of driving surfaces, the plurality of wedge members extending within the plurality of latch openings about and between a released position and a locked position,
wherein each wedge member of the plurality of wedge members is unattached to other portions of the core barrel head assembly, and
wherein, when the plurality of wedge members are positioned in the locked position, the driving member is configured to wedge the plurality of wedge members between portions of the inner surface of the drill string and respective portions of the plurality of driving surfaces to axially and rotationally lock the core barrel head assembly relative to the drill string.
14. The core barrel head assembly as recited in claim 13 , wherein at a selected axial position relative to the longitudinal axis of the drill string, the distance between the inner surface of the drill string and the driving member varies circumferentially about the driving member.
15. The core barrel head assembly as recited in claim 13 , wherein the driving member is configured to wedge the plurality of wedge members between the inner surface of the drill string and the plurality of driving surfaces upon rotation of the drill string.
16. The core barrel head assembly as recited in claim 13 , further comprising:
a latch body moveably coupled to the sleeve;
a landing member positioned at least partially within the latch body; and
a plurality of braking elements positioned on the landing member, wherein axial movement of the landing member relative to the plurality of braking elements moves the plurality of braking elements radially relative to the latch body between a retracted position and an extended position.
17. The core barrel head assembly as recited in claim 16 , further comprising a biasing member, wherein the biasing member biases the plurality of driving surfaces against the plurality of wedge members.
18. The core barrel head assembly as recited in claim 17 , wherein the biasing member biases the landing member against the plurality of braking elements.