# US 11,027,768 B2 · Steer by wire road vehicle steering system provided with a mechanical limit stop device for the steering wheel > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,027,768 B2 - Document ID: US11027768B2 - Status: Granted - Kind: B2 - Application number: 16/171,445 - Filed: 2018-10-26 - Published: 2019-05-02 - Granted: 2021-06-08 - Earliest claimed: 2017-10-26 - Assignees: Ferrari S.P.A. - Applicants: Ferrari S.p.A. - Inventors: Franco Cimatti - Web page: https://patentgrep.com/patent/US11027768B2 ## CPC - B62D 5/001: {Mechanical components or aspects of steer-by-wire systems, not otherwise provided for in this maingroup} - B62D 1/105: {Non-rotatable hubs, e.g. the central part of the steering wheel not rotating} - B62D 1/181: with power actuated adjustment, e.g. with position memory - B62D 1/185: adjustable by axial displacement, e.g. telescopically (B62D1/183, B62D1/187, B62D1/19 take precedence) - B62D 5/006: {power actuated} - B62D 5/0421: {Electric motor acting on or near steering gear} - F16H 25/20: Screw mechanisms (with automatic reversal F16H25/12) - 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) - F16H: GEARING ## Abstract A steering system for a road vehicle; the steering system comprises: a steering wheel provided with an outer ring, which is mounted so as to rotate around a rotation axis and has no connection to steering wheels; a position sensor, which is designed to detect the angular position of the outer ring of the steering wheel around the rotation axis; and a mechanical limit stop device, which is coupled to the outer ring of the steering wheel and limits, in both directions, the maximum angular width of the rotation of the steering wheel around the rotation axis, so that the steering wheel can make, on the whole, a rotation around the rotation axis that is greater than 360°. ## Claims ### Claim 1 A steering system (4) for a road vehicle (1); the steering system (4) comprises: a steering wheel (6) provided with an outer ring (15), which is mounted so as to rotate around a rotation axis (13) and has no connection to steering wheels (2); a position sensor (8), which is designed to detect the angular position of the outer ring (15) of the steering wheel (6) around the rotation axis (13); and a mechanical limit stop device (30), which is coupled to the outer ring (15) of the steering wheel (6) and limits, in both directions, the maximum angular width of the rotation of the steering wheel (6) around the rotation axis (13), so that the steering wheel (6) can make, on the whole, a rotation around the rotation axis (13) that is greater than 360°; wherein the limit stop device (30) comprises: a groove (31), which is wound in a spiral shape around the rotation axis (13) over more than 360° and has, at the two opposite ends, two abutments (32), which define respective stop strikers; and a pin (33), which is arranged on the inside of the groove (31) so as to engage and follow the groove (31) from an abutment (32) to the opposite abutment (32); wherein the groove (31) is angularly integral to the outer ring (15) of the steering wheel (6) to rotate in an angularly integral manner with the steering wheel (6) and in use can axially slide relative to the outer ring (15) of the steering wheel (6) to allow the rotation of the steering wheel (6); and wherein the pin (33) is rigidly connected to a part that does not rotate together with the outer ring (15) of the steering wheel (6) and cannot slide relative to the outer ring (15) of the steering wheel (6). ### Claim 2 (depends on 1) A steering system (4) according to claim 1, wherein: a support element (21) is provided, which, on one side, can be rigidly fixed on the inside of the vehicle (1) and, on the other side, is connected to the steering wheel (6) so as to support the steering wheel (6); and the pin (33) is angularly integral to the support element (21). ### Claim 3 (depends on 1) A steering system (4) according to claim 1, wherein the groove (31) is angularly integral to the outer ring (15) of the steering wheel (6) through a splined coupling. ### Claim 4 (depends on 1) A steering system (4) according to claim 1 and comprising a first electric motor (16), which supports the steering wheel (6), applies a variable feedback torque to the outer ring (15) of the steering wheel (6), and comprises a stator (17) and a rotor (18), which is rigidly connected to the outer ring (15) of the steering wheel (6). ### Claim 5 (depends on 1) A steering system (4) according to claim 1 and comprising a second electric motor (10), which is mechanically completely independent of and separate from the steering wheel (6) and is designed to control the steering of steering wheels (2) of the vehicle (1). ### Claim 6 (depends on 5) A steering system (4) according to claim 5 and comprising a control unit (12), which is connected to the position sensor (8) so as to receive the reading of the angular position of the steering wheel (6) and is designed to control the second electric motor (10) so as to adjust the steering of the steering wheels (2) of the vehicle (1) based on the angular position of the steering wheel (6). ### Claim 7 (depends on 1) A steering system (4) according to claim 1, wherein: a support element (21) is provided, which, on one side, can be rigidly fixed on the inside of the vehicle (1) and, on the other side, is connected to the steering wheel (6) so as to support the steering wheel (6); and the support element (21) is telescopic so as to vary its axial size along the rotation axis (13) in order to change the axial position of the steering wheel (6). ### Claim 8 (depends on 7) A steering system (4) according to claim 7, wherein the support element (21) comprises: an outer body (22), which can be rigidly fixed on the inside of the vehicle (1) and is internally hollow; an inner body (24), which is connected to the steering wheel (6), is partially arranged on the inside of the outer body (22), and can axially slide relative to the outer body (22); and an actuator device (26) is designed to axially translate the inner body (24) relative to the outer body (22) and is arranged on the inside of the outer body (22). ### Claim 9 (depends on 8) A steering system (4) according to claim 8, wherein the outer body (22) is tubular and has, on the inside, a chamber (23), which is open on one side, partially houses the inner body (24) in an axially sliding manner, and houses the actuator device (26). ### Claim 10 (depends on 8) A steering system (4) according to claim 8, wherein the actuator device (26) is designed to stop the axial translation between the outer body (22) and the inner body (24) so as to make sure that, in use, the steering wheel (6) remains still in a predefined axial position. ### Claim 11 (depends on 8) A steering system (4) according to claim 8, wherein the actuator device (26) is active and comprises a third electric motor, which causes an axial translation movement of the inner body (24) relative to the outer body (22). ### Claim 12 (depends on 11) A steering system (4) according to claim 11, wherein the actuator device (26) comprises: the third electric motor, which is integral to the outer body (22); a worm screw, which is caused to rotate by the third electric motor; and an abutment, which is screwed in the worm screw and is integral to the inner body (24).