# US 9,435,167 B2 · Downhole driving unit having a hydraulic motor in a wheel > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,435,167 B2 - Document ID: US9435167B2 - Status: Granted - Kind: B2 - Application number: 14/008,190 - Filed: 2012-03-29 - Published: 2014-01-16 - Granted: 2016-09-06 - Earliest claimed: 2011-03-30 - Assignees: Welltec A/S - Applicants: Jørgen Hallundbæk - Inventors: Jørgen Hallundbæk - Web page: https://patentgrep.com/patent/US9435167B2 ## CPC - E21B 23/001: {Self-propelling systems or apparatus, e.g. for moving tools within the horizontal portion of a borehole} - B60K 7/0015: {the motor being hydraulic} - E21B 4/02: Fluid rotary type drives - E21B 4/18: Anchoring or feeding in the borehole - E21B 23/00: Apparatus for displacing, setting, locking, releasing or removing tools, packers or the like in boreholes or wells (setting of casings, screens or liners E21B43/10) - E21B 23/04: operated by fluid means, e.g. actuated by explosion (E21B23/08 takes precedence) - E21B 29/002: {Cutting, e.g. milling, a pipe with a cutter rotating along the circumference of the pipe} - B60K 17/046: {with planetary gearing having orbital motion} - B60K 2007/0038: {the motor moving together with the wheel axle} - B60K 2007/0092: {the motor axle being coaxial to the wheel axle} - B60Y 2200/60: Industrial applications, e.g. pipe inspection vehicles - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS - B60K: ARRANGEMENT OR MOUNTING OF PROPULSION UNITS OR OF TRANSMISSIONS IN VEHICLES; ARRANGEMENT OR MOUNTING OF PLURAL DIVERSE PRIME-MOVERS IN VEHICLES; AUXILIARY DRIVES FOR VEHICLES; INSTRUMENTATION OR DASHBOARDS FOR VEHICLES; ARRANGEMENTS IN CONNECTION WITH COOLING, AIR INTAKE, GAS EXHAUST OR FUEL SUPPLY OF PROPULSION UNITS IN VEHICLES - B60Y: INDEXING SCHEME RELATING TO ASPECTS CROSS-CUTTING VEHICLE TECHNOLOGY ## Abstract The present invention relates to a downhole driving unit (11) for insertion into a well, comprising a driving unit housing (51), an arm assembly (60) movable between a retracted position and a projecting position in relation to the driving unit housing, an arm activation assembly (41) arranged in the driving unit housing for moving the arm assembly between the retracted position and the projecting position and a wheel assembly (90) comprising a stationary part (91) and a rotational part (92), the stationary part being connected with or forming part of the arm assembly and being rotatably connected with a rotational part. The wheel assembly comprises a hydraulic motor comprising a hydraulic motor housing (93) and a rotatable section (84) connected with the rotational part for rotating part of the wheel assembly. Furthermore, the present invention relates to a downhole system comprising said driving unit and to use of such driving unit. ## Claims ### Claim 1 A downhole driving unit for insertion into a well, comprising: a driving unit housing, an arm assembly movable between a retracted position and a projecting position in relation to the driving unit housing, an arm activation assembly arranged in the driving unit housing for moving the arm assembly between the retracted position and the projecting position, and a wheel assembly comprising a stationary part and a rotational part, the stationary part being connected with or forming part of the arm assembly and being rotatably connected with the rotational part, wherein the wheel assembly comprises a hydraulic motor comprising a hydraulic motor housing and a rotatable section connected with the rotational part for rotating part of the wheel assembly, wherein the arm assembly comprises a wheel arm and the wheel arm comprises fluid channels for providing fluid to and from the hydraulic motor through the stationary part. ### Claim 2 (depends on 1) A downhole driving unit according to claim 1, wherein the stationary part and the rotational part constitute the hydraulic motor housing. ### Claim 3 (depends on 1) A downhole driving unit according to claim 1, wherein the wheel assembly further comprises a planetary gearing system. ### Claim 4 (depends on 3) A downhole driving unit according to claim 3, wherein the planetary gearing system is comprised in the hydraulic motor housing. ### Claim 5 (depends on 3) A downhole driving unit according to claim 3, wherein the wheel assembly comprises a wheel ring. ### Claim 6 (depends on 3) A downhole driving unit according to claim 3, wherein the rotatable section of the hydraulic motor is connected with a sun gear of the planetary gearing system. ### Claim 7 (depends on 6) A downhole driving unit according to claim 6, wherein the sun gear of the planetary gearing system drives a plurality of planet gears which are connected through a carrier member for driving a ring gear of the planetary gearing system. ### Claim 8 (depends on 7) A downhole driving unit according to claim 7, wherein the wheel assembly comprises a wheel ring, and the wheel ring comprises the ring gear, enabling the planet gears to engage and drive the wheel ring. ### Claim 9 (depends on 3) A downhole driving unit according to claim 3, wherein the planetary gearing system comprises a ring gear constituted by a wheel ring or a closing member. ### Claim 10 (depends on 3) A downhole driving unit according to claim 3, wherein the rotatable section of the hydraulic motor is connected with planet gears and the planet gears are driven by the rotatable section. ### Claim 11 (depends on 3) A downhole driving unit according to claim 3, wherein the rotatable section of the hydraulic motor comprises a first sun gear of the planetary gearing system and the first sun gear drives a plurality of first planet gears which are connected through a carrier member. ### Claim 12 (depends on 11) A downhole driving unit according to claim 11, wherein the carrier member of the planetary gearing system drives a plurality of second planet gears and the carrier member comprises the sun gear engaging and driving the second planet gears. ### Claim 13 (depends on 12) A downhole driving unit according to claim 12, wherein the second planet gears are connected by means of a second carrier member being part of the rotational part for rotating part of the wheel assembly. ### Claim 14 (depends on 1) A downhole driving unit according to claim 1, wherein the hydraulic motor comprises fluid channels arranged in alignment with the fluid channels in the wheel arm so that fluid is led from the wheel arm to cylinders in the hydraulic motor. ### Claim 15 (depends on 1) A downhole driving unit according to claim 1, wherein the hydraulic motor is a radial piston motor. ### Claim 16 (depends on 1) A downhole driving unit according to claim 1, wherein the hydraulic motor comprises a cam ring connected with or forming part of the stationary part of the wheel assembly. ### Claim 17 (depends on 1) A downhole system comprising the driving unit according to claim 1 and an operational tool connected with the driving unit for being moved forward in a well or borehole. ### Claim 18 (depends on 17) A downhole system according to claim 17, wherein the operational tool is a stroker tool, a key tool, a milling tool, a drilling tool, a logging tool, etc.