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A valve assembly for use in an inner tube member of a core barrel head assembly positionable within a drill string of a drilling apparatus. The piston member of the valve assembly is located between a fluid pressure communication port and a fluid flow port to hold the retracting case in an up positi

A valve assembly for use in an inner tube member of a core barrel head assembly positionable within a drill string of a drilling apparatus. The piston member of the valve assembly is located between a fluid pressure communication port and a fluid flow port to hold the retracting case in an up position and the latches retracted. After an increased fluid pressure has pushed the piston member past the annular element or bushing, the piston member substantially restricts fluid flow through the bushing and allows the retracting case to move to a down position and extend the latches. If the latches are not extended due to an obstruction or misalignment, the retracting case will prevent the piston member from completely passing through the bushing, thus maintaining high fluid pressure due to the flow ports remaining closed, and indicating to the driller that the latches have not properly latched.

대표청구항 ▼

1. A core barrel head assembly positionable within a drill string of a drilling apparatus, the core barrel head assembly comprising: an inner tube assembly; andan inner tube member, disposed within the inner tube assembly and axially displaceable with respect to the inner tube assembly, the inner tu

1. A core barrel head assembly positionable within a drill string of a drilling apparatus, the core barrel head assembly comprising: an inner tube assembly; andan inner tube member, disposed within the inner tube assembly and axially displaceable with respect to the inner tube assembly, the inner tube member comprising: a landing shoulder;at least one upstream fluid flow port positionable within a fluid line of the drilling apparatus upstream of the landing shoulder;at least one downstream fluid flow port positionable within the fluid line of the drilling apparatus downstream of the landing shoulder;at least one fluid pressure communication port positionable within the fluid line of the drilling apparatus;an annular element positioned within the inner tube member;a piston member mounted for axial movement within the inner tube member, traversable through the annular element and cooperable therewith to be configured by default to sealingly engage the annular element;a valve member mounted for axial movement within a central bore of the inner tube member, the valve member positionable between a blocking position for blocking fluid flow between the upstream fluid flow port and the central bore and an unblocking position for allowing fluid flow between the upstream fluid flow port and the central bore, wherein the valve member is axially connected to the piston member;a latching mechanism lockingly positionable between a latched configuration and an unlatched configuration; anda retracting case mounted for axial movement about the inner tube member, axial displacement of the retracting case being driven by a corresponding axial displacement of the piston member, the retracting case cooperating with the latching mechanism, such that the latching mechanism remains in a locked unlatched configuration for reducing drag of the latching mechanism on the drill string,wherein, upon the fluid pressure reaching said predetermined value through the at least one pressure communication port, said fluid pressure urges the piston member to traverse the annular member, thereby displacing the valve member from the blocking position to the unblocking position, and thereby allowing the latching mechanism to be positioned in a locked latched configuration. 2. The core barrel head assembly according to claim 1, wherein the valve member and piston member are integral to each other. 3. The core barrel head assembly according to claim 1, further comprising a connecting rod axially connecting the piston member to the valve member. 4. The core barrel head assembly according to claim 1, wherein the annular member is at least one of a gasket and a O-Ring. 5. The core barrel head assembly according to claim 1, further comprising: a seal member surrounding the valve member. 6. The core barrel head assembly according to claim 1, wherein the predetermined value of fluid pressure is selected to correspond to a built up fluid pressure when the inner tube member reaches an end of the drill string. 7. The core barrel head assembly according to claim 1, wherein upon at least one of an obstruction and a misalignment of the inner tube member maintaining the latching mechanism in the unlatched configuration, the retracting case, cooperating with said latching mechanism, prevents the piston member from disengaging from the annular member. 8. The core barrel head assembly according to claim 1, further comprising: a spearhead connected to the retracting case, wherein a retrieval force exerted on the spearhead pulls the retracting case, thereby urging the latching mechanism towards an unlatched configuration, urging the piston member towards sealed engagement with the annular member, past the annular member thereafter and urging the valve member towards a position partially blocking the at least one fluid flow port. 9. The core barrel head assembly according to claim 1, wherein the piston member comprises: a slotted aperture;a linking member slideable within the slotted aperture and connected to the retracting case; anda biasing element for urging the linking member towards abutted engagement with an extremity of the slotted aperture within the piston member. 10. A core barrel head assembly positionable within a drill string of a drilling apparatus, the core barrel head assembly comprising: an inner tube assembly; andan inner tube member, disposed within the inner tube assembly and axially displaceable with respect to the inner tube assembly, the inner tube member comprising: a landing shoulder;at least one upstream fluid flow port positionable within a fluid line of the drilling apparatus upstream of the landing shoulder and in fluid communication with a central bore formed in the inner tube member;at least one downstream fluid flow port positionable within the fluid line of the drilling apparatus downstream of the landing shoulder;at least one fluid pressure communication port positionable within the fluid line of the drilling apparatus;an annular element positioned within the inner tube member;a piston member mounted for axial movement within the inner tube member, traversable through the annular element and cooperable therewith to be configured by default to sealingly engage the annular element in sealed engagement when subjected to a fluid pressure under a predetermined value;a latching mechanism lockingly positionable between a latched configuration and an unlatched configuration; anda retracting case mounted for axial movement about the inner tube member, axial displacement of the retracting case being driven by a corresponding axial displacement of the piston member, the retracting case cooperating with the latching mechanism, such that the latching mechanism remains in a locked unlatched configuration for reducing drag of the latching mechanism on the drill string, the retracting case further comprising a valve member positionable between a blocking position for blocking fluid flow between the upstream fluid flow port and the central bore and an unblocking position for allowing fluid flow between the upstream fluid flow port and the central bore;wherein, upon the fluid pressure reaching said predetermined value through the at least one pressure port, said fluid pressure urges the piston member to traverse the annular member, thereby displacing the valve member of the retracting case from the blocking position to the unblocking position, and thereby allowing the latching mechanism to be positioned in the latched configuration. 11. The core barrel head assembly according to claim 10, wherein the annular member is at least one of a gasket and a O-Ring. 12. The core barrel head assembly according to claim 10, wherein the predetermined value of fluid pressure is selected to correspond to a built up fluid pressure when the inner tube member reaches an end of the drill string. 13. The core barrel head assembly according to claim 10, wherein upon at least one of an obstruction and a misalignment of the inner tube member maintaining the latching mechanism in the unlatched configuration, the retracting case, cooperating with said latching mechanism, prevents the piston member from disengaging from the annular member. 14. The core barrel head assembly according to claim 10, further comprising: a spearhead connected to the retracting case, wherein a retrieval force exerted on the spearhead pulls the retracting case, thereby urging the latching mechanism towards an unlatched configuration, urging the piston member towards sealed engagement with the annular member and urging the valve member towards a position partially blocking the at least one fluid flow port. 15. A core barrel head assembly positionable within a drill string of a drilling apparatus, the core barrel head assembly comprising: an inner tube assembly; andan inner tube member, disposed within the inner tube assembly and axially displaceable with respect to the inner tube assembly, the inner tube member comprising: a landing shoulder;a piston member mounted for axial movement within the inner tube member;a latching mechanism lockingly positionable between a latched configuration and an unlatched configuration; anda retracting case mounted for axial movement about the inner tube member, axial displacement of the retracting case being driven by a corresponding axial displacement of the piston member, the retracting case cooperating with the latching mechanism;wherein the piston member comprises: a slotted aperture;a linking member slideable within the slotted aperture and connected to the retracting case; anda biasing element for urging the linking member towards abutted engagement with an extremity of the slotted aperture within the piston member and for absorbing momentum of the core barrel head assembly upon landing thereof.