# US 2017/0282961 A1 · Work vehicle > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0282961 A1 - Document ID: US20170282961A1 - Status: Published application - Kind: A1 - Application number: 15/108,354 - Filed: 2016-03-31 - Published: 2017-10-05 - Earliest claimed: 2016-03-31 - Assignees: Komatsu Ltd. - Applicants: Komatsu Ltd. - Inventors: Yuichi TERANISHI - Web page: https://patentgrep.com/patent/US20170282961A1 ## CPC - B62D 1/22: Alternative steering-control elements, e.g. for teaching purposes - E02F 9/0841: {Articulated frame, i.e. having at least one pivot point between two travelling gear units (tractor-trailer combinations B62D53/00)} - E02F 9/2004: {Control mechanisms, e.g. control levers (control levers per se G05G)} - E02F 9/2012: {Setting the functions of the control levers, e.g. changing assigned functions among operations levers, setting functions dependent on the operator or seat orientation} - E02F 9/2087: {Control of vehicle steering (for steering with hydraulic or pneumatic drives E02F9/225)} - E02F 9/24: Safety devices {, e.g. for preventing overload (E02F9/226 takes precedence)} - E02F 9/268: {with failure correction follow-up actions} - E02F 3/34: with bucket-arms {, i.e. a pair of arms, e.g. manufacturing processes, form, geometry, material of bucket-arms (with a single arm E02F3/283)} directly pivoted on the frames of tractors or self-propelled machines - E02F 9/16: Cabins, platforms, or the like, for drivers ({for motor vehicles in general B62D33/06}, for cranes B66C13/54) - B62D: MOTOR VEHICLES; TRAILERS (steering, or guiding on a desired track, of agricultural machines or implements A01B69/00; wheels, castors, axles, increasing wheel adhesion B60B; vehicle tyres, tyre inflation or tyre changing B60C; connections between vehicles of a train or the like B60D; vehicles for use on rail and road, amphibious or convertible vehicles B60F; suspension arrangements B60G; heating, cooling, ventilating or other air treating devices B60H; windows, windscreens, non-fixed roofs, doors or similar devices, protective coverings for vehicles not in use B60J; propulsion plant arrangements, auxiliary drives, transmissions, controls, instrumentation or dashboards B60K; electric equipment or propulsion of electrically-propelled vehicles B60L; power supply for electrically-propelled vehicles B60M; passenger accommodation not otherwise provided for B60N; adaptations for load transportation or to carry special loads or objects B60P; arrangement of signalling or lighting devices, the mounting or supporting thereof or circuits therefor, for vehicles in general B60Q; vehicles, vehicle fittings or vehicle parts not otherwise provided for B60R; servicing, cleaning, repairing, supporting, lifting, or manoeuvring, not otherwise provided for, B60S; brake arrangements, brake control systems or parts thereof B60T; air-cushion vehicles B60V; motor-cycles, accessories therefor B62J, B62K; testing of vehicles G01M) - E02F: DREDGING; SOIL-SHIFTING (winning peat E21C49/00) ## Abstract A controller disables the motion of a steering cylinder brought about by a steering lever when an enabled state is selected via a lever switch and an instruction to start an engine is issued via a main switch. ## Claims ### Claim 1 A work vehicle comprising: a steering lever; an engine; a main switch configured to instruct an engine start; a rear frame; a front frame rotatably attached to the rear frame; a steering actuator attached between the front frame and the rear frame and caused configured to move in response to an operating state of the steering lever; a lever switch configured to allow the selection of either an enabled state or a disabled state of a motion of the steering actuator brought about by the steering lever; and a lever steering control unit configured to set the motion of the steering actuator brought about by the steering lever to the disabled state when the enabled state is selected via the lever switch and the engine start is instructed via the main switch. ### Claim 2 (depends on 1) The work vehicle according to claim 1, wherein the main switch is configured to allow the selection of any of a first position in which electrical power is not supplied to the lever steering control unit, a second position in which electrical power is supplied to the lever steering control unit, and a third position for instructing the engine start; and when the engine is stopped while the enabled state is selected via the lever switch, the lever steering control unit disables the motion of the steering actuator brought about by the steering lever when the main switch is switched from the second position to the third position. ### Claim 3 (depends on 2) The work vehicle according to claim 2, wherein when the engine is stopped while the enabled state is selected via the lever switch, the lever steering control unit maintains the motion of the steering actuator brought about by the steering lever in the enabled state until the main switch is switched from the second position to the third position. ### Claim 4 (depends on 2) The work vehicle according to claim 2, wherein when the lever steering control unit receives a signal for instructing the engine start, the lever steering control unit stops the output of a motion instruction to the steering actuator corresponding to an operation of the steering lever. ### Claim 5 (depends on 2) The work vehicle according to claim 2, further comprising a battery connected to the main switch, the lever steering control unit being provided with a relay circuit that, when the main switch is switched from the second position to the third position, shuts off electrical power supplied from the battery. ### Claim 6 (depends on 3) The work vehicle according to claim 3, wherein when the lever steering control unit receives a signal for instructing the engine start, the lever steering control unit stops the output of a motion instruction to the steering actuator corresponding to an operation of the steering lever. ### Claim 7 (depends on 3) The work vehicle according to claim 3, further comprising a battery connected to the main switch, the lever steering control unit being provided with a relay circuit that, when the main switch is switched from the second position to the third position, shuts off electrical power supplied from the battery.