# US 11,110,955 B2 · Electric steering device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,110,955 B2 - Document ID: US11110955B2 - Status: Granted - Kind: B2 - Application number: 16/857,515 - Filed: 2020-04-24 - Published: 2020-12-03 - Granted: 2021-09-07 - Earliest claimed: 2019-05-29 - Assignees: Denso Corporation - Applicants: Denso Corporation - Inventors: Syuhei Miyachi - Web page: https://patentgrep.com/patent/US11110955B2 ## CPC - B62D 5/046: {Controlling the motor} - B62D 5/0487: {detecting motor faults (B62D5/0496 takes precedence)} - H02M 1/32: Means for protecting converters other than automatic disconnection - H02M 7/003: {Constructional details, e.g. physical layout, assembly, wiring or busbar connections} - H02M 7/53871: {with automatic control of output voltage or current} - H02P 25/22: Multiple windings; Windings for more than three phases - H02P 27/08: with pulse width modulation - H02P 29/032: Preventing damage to the motor, e.g. setting individual current limits for different drive conditions - B62D 5/0403: {characterised by constructional features, e.g. common housing for motor and gear box} - B62D 5/0412: {the axes of motor and steering column being parallel} - 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) - H02M: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF (transformers H01F; dynamo-electric converters H02K47/00; controlling transformers, reactors or choke coils, control or regulation of electric motors, generators or dynamo-electric converters H02P) - H02P: CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS ## Abstract An electric steering device includes a motor and a control circuit. The motor applies a steering force to a steering mechanism of a vehicle. The control circuit includes an inverter that converts DC power of a DC power supply to AC power and supplies the AC power to the motor, and a power supply relay that permits or blocks a current flow to the motor through the inverter. In the control circuit, the power supply relay is provided on a ground line connecting the inverter and a ground. ## Claims ### Claim 1 An electric steering device, comprising: a motor that applies a steering force to a steering mechanism of a vehicle; and a control circuit that controls the motor, and includes an inverter that converts DC power supplied from a DC power supply to AC power and supplies the AC power to the motor, and a power supply relay that permits or blocks a current flow to the motor through the inverter, wherein in the control circuit, the power supply relay is disposed on a ground line connecting the inverter and a ground. ### Claim 2 (depends on 1) The electric steering device according to claim 1, wherein the power supply relay is configured to be turned on with a drive voltage that is equal to or lower than a voltage of the DC power supply. ### Claim 3 (depends on 1) The electric steering device according to claim 1, wherein the control circuit further includes a reverse connection protection relay that blocks a current flow in a direction opposite to the current flow permitted by the power supply relay. ### Claim 4 (depends on 3) The electric steering device according to claim 3, wherein the reverse connection protection relay is provided on the ground line in the control circuit. ### Claim 5 (depends on 4) The electric steering device according to claim 4, wherein the power supply relay and the reverse connection protection relay include switching elements having parasitic diodes, respectively, and anodes of the parasitic diodes are connected together. ### Claim 6 (depends on 1) The electric steering device according to claim 1, wherein the motor has a plurality of stator coils, the control circuit has a plurality of circuit systems configured to be redundant in correspondence to the stator coils, and each of the circuit systems has the power supply relay provided on the ground line. ### Claim 7 (depends on 1) The electric steering device according to claim 1, wherein the motor has a plurality of stator coils, the control circuit has a plurality of circuit systems configured to be redundant in correspondence to the stator coils, a part of the plurality of circuit systems has the power supply relay provided on the ground line, as a first power supply relay, a remaining of the plurality of circuit systems has a second power supply relay that is provided on a power supply line connecting the DC power supply and the inverter, and the second power supply relay permits or blocks a current flow to the motor through the inverter. ### Claim 8 (depends on 1) The electric steering device according to claim 1, wherein the control circuit includes a substrate having a wiring pattern and a connector mounted on the substrate, the wiring pattern provides the ground line, the connector includes a ground terminal, and on the substrate, the power supply relay is disposed at a position closer than the inverter to a connection of the ground terminal. ### Claim 9 (depends on 8) The electric steering device according to claim 8, wherein on the substrate, the power supply relay is disposed on a surface different from a surface on which the inverter is disposed. ### Claim 10 (depends on 1) The electric steering device according to claim 1, wherein the control circuit includes a substrate having a wiring pattern that provides the ground line, the motor has a metal housing, the substrate is fixed to the housing through a metal fixing member, and on the substrate, the power supply relay is disposed at a position closer than the inverter to a fixing part of the fixing member. ### Claim 11 (depends on 9) The electric steering device according to claim 9, wherein the fixing member is electrically connected to the wiring pattern.