US 12,491,934 B2
Steering device
Atsushi Yoshitake, Higashimatsuyama (JP); and Shigeru Mochizuki, Saitama (JP)
Assigned to KNORR-BREMSE COMMERCIAL VEHICLE SYSTEMS JAPAN LTD., Sakado (JP)
Appl. No. 18/294,605
Filed by KNORR-BREMSE COMMERCIAL VEHICLE SYSTEMS JAPAN LTD., Sakado (JP)
PCT Filed Jun. 16, 2022, PCT No. PCT/JP2022/024113
§ 371(c)(1), (2) Date Feb. 2, 2024,
PCT Pub. No. WO2023/013258, PCT Pub. Date Feb. 9, 2023.
Claims priority of application No. 2021-128260 (JP), filed on Aug. 4, 2021.
Prior Publication US 2024/0343299 A1, Oct. 17, 2024
Int. Cl. B62D 5/32 (2006.01); B62D 5/04 (2006.01); B62D 5/06 (2006.01); B62D 5/065 (2006.01); B62D 5/083 (2006.01); B62D 5/12 (2006.01); B62D 6/00 (2006.01)
CPC B62D 5/32 (2013.01) [B62D 5/04 (2013.01); B62D 5/046 (2013.01); B62D 5/06 (2013.01); B62D 5/064 (2013.01); B62D 5/065 (2013.01); B62D 5/083 (2013.01); B62D 5/12 (2013.01); B62D 6/00 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A steering device comprising:
a steering shaft structured to receive rotation from a steering wheel;
a transmitting mechanism structured to transmit rotation from the steering shaft to a turning wheel;
a power cylinder that includes a piston disposed in the transmitting mechanism, and includes a pair of liquid chambers defined by the piston, and is structured to provide hydraulic assist torque for steering the turning wheel;
a rotary valve structured to supply hydraulic liquid to the pair of liquid chambers selectively depending on rotation of the steering shaft;
an electric motor structured to provide a motor assist torque for the steering shaft;
a torque sensor structured to measure a steering torque based on rotation of the steering shaft; and
a control unit configured to:
determine a hydraulic abnormality to be present in the pair of liquid chambers, in response to satisfaction of a condition that a total torque of the steering torque and the motor assist torque is greater than a predetermined threshold torque;
increase the motor assist torque of the electric motor in response to a determination that the hydraulic abnormality is present; and
stop increasing the motor assist torque of the electric motor in response to satisfaction of a condition that an absolute value of the total torque is equal to or less than 5 Nm.