# US 8,464,811 B2 · Steerable system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,464,811 B2 - Document ID: US8464811B2 - Status: Granted - Kind: B2 - Application number: 12/808,519 - Filed: 2008-12-19 - Published: 2011-05-05 - Granted: 2013-06-18 - Earliest claimed: 2007-12-19 - Assignees: Schlumberger Technology Corporation - Applicants: Michael Shepherd - Inventors: Michael Shepherd - Web page: https://patentgrep.com/patent/US8464811B2 ## CPC - E21B 7/06: Deflecting the direction of boreholes - A61F 13/15747: {Folding; Pleating; Coiling; Stacking; Packaging} - B65H 29/60: diverting the stream into alternative paths (B65H29/62 takes precedence) - B65H 29/62: diverting faulty articles from the main streams (control devices detecting faulty articles B65H43/04) - E21B 7/062: {the tool shaft rotating inside a non-rotating guide travelling with the shaft (E21B7/067 and E21B7/068 take precedence)} - E21B 7/067: {with means for locking sections of a pipe or of a guide for a shaft in angular relation, e.g. adjustable bent sub} - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS - A61F: FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS (dental prosthetics A61C) - B65H: HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES ## Abstract A steerable system comprises a first rotatable housing and a second rotatable housing connected to the first rotatable housing by an adjustable joint. A cam member is held against rotation while in use. Cam follower means are cooperable with the cam member and moveable to drive the second rotatable housing for movement relative to the first rotatable housing about the adjustable joint. ## Claims ### Claim 1 A steerable system comprising a first rotatable housing, a second rotatable housing connected to the first rotatable housing by an adjustable joint, a cam member held against rotation, in use, and a cam follower cooperable with the cam member, the cam follower comprising follower pistons which are reciprocable in corresponding bores, the follower pistons causing movement of associated drive members in a manner which provides mechanical advantage enabling the associated drive members to apply a larger force, the associated drive members being moveable to drive the second rotatable housing for movement relative to the first rotatable housing about the adjustable joint. ### Claim 2 (depends on 1) A system according to claim 1, wherein the first and second rotatable housings are connected to one another in such a manner that rotation of the first housing is transmitted to the second housing. ### Claim 3 (depends on 2) A system according to claim 2, further comprising a clutch mechanism operable to allow rotation of the first housing relative to the second housing. ### Claim 4 (depends on 3) A system according to claim 3, wherein the clutch mechanism comprises a dog clutch. ### Claim 5 (depends on 1) A system according to claim 1, wherein the cam member is adjustable to permit adjustment of the orientation of the second housing. ### Claim 6 (depends on 1) A system according to claim 1, wherein the cam member is mounted to a sleeve which surrounds at least part of the first housing and which is held against rotation in normal use. ### Claim 7 (depends on 6) A system according to claim 6, wherein the sleeve comprises a stabiliser. ### Claim 8 (depends on 6) A system according to claim 6, wherein a spherical bearing is provided and arranged to support the cam member relative to the sleeve. ### Claim 9 (depends on 6) A system according to claim 6, wherein one or more linear actuators are provided to drive the cam member for movement relative to the sleeve to adjust its position. ### Claim 10 (depends on 9) A system according to claim 9, wherein the or each linear actuator is electrically driven, electromagnetically driven or is hydraulically powered. ### Claim 11 (depends on 6) A system according to claim 6, wherein the cam member is in the form of a swash plate. ### Claim 12 (depends on 1) A system according to claim 1, wherein the cam followers comprise follower pistons arranged to be driven by the cam member and moveable to cause movement of drive pistons. ### Claim 13 (depends on 12) A system according to claim 12, wherein the follower pistons are of smaller diameter than the drive pistons so as to provide a mechanical advantage. ### Claim 14 (depends on 12) A system according to claim 12, wherein movement of the drive pistons is transmitted to the second housing by associated push rods. ### Claim 15 (depends on 14) A system according to claim 14, wherein the push rods are aligned with the corresponding ones of the follower pistons. ### Claim 16 (depends on 1) A system according to claim 1, wherein the associated drive members comprise associated drive pistons. ### Claim 17 (depends on 1) A system according to claim 1, wherein the cam member is mounted to a sleeve which surrounds at least part of the first housing and which is held against rotation in normal use. ### Claim 18 (depends on 17) A system according to claim 17, wherein the sleeve comprises a stabiliser. ### Claim 19 (depends on 18) A system according to claim 18, further comprising a spherical bearing positioned to support the cam member relative to the sleeve. ### Claim 20 (depends on 19) A system according to claim 19, further comprising linear actuators oriented to drive the cam member for movement relative to the sleeve to adjust its position. ### Claim 21 (depends on 16) A system according to claim 16, wherein the associated drive pistons have larger diameters than the follower pistons such that each associated drive piston is moved over a smaller distance than the corresponding follower piston when acted on by the corresponding follower piston to provide the mechanical advantage.