US 12,116,054 B2
Steering device
Yukio Uchida, Higashimatsuyama (JP); Toshiro Yoda, Higashimatsuyama (JP); Shogo Ishikawa, Higashimatsuyama (JP); and Satoshi Kubosawa, Higashimatsuyama (JP)
Assigned to Knorr-Bremse Commercial Vehicle Systems Japan Ltd., Saitama (JP)
Appl. No. 17/429,703
Filed by Knorr-Bremse Commercial Vehicle Systems Japan Ltd., Sakado (JP)
PCT Filed Dec. 16, 2019, PCT No. PCT/JP2019/049101
§ 371(c)(1), (2) Date Aug. 10, 2021,
PCT Pub. No. WO2020/170579, PCT Pub. Date Aug. 27, 2020.
Claims priority of application No. 2019-026915 (JP), filed on Feb. 18, 2019.
Prior Publication US 2022/0126912 A1, Apr. 28, 2022
Int. Cl. B62D 5/06 (2006.01); B62D 5/065 (2006.01); B62D 5/083 (2006.01); B62D 5/09 (2006.01); B62D 5/30 (2006.01); B62D 5/04 (2006.01)
CPC B62D 5/092 (2013.01) [B62D 5/064 (2013.01); B62D 5/065 (2013.01); B62D 5/083 (2013.01); B62D 5/30 (2013.01); B62D 5/0463 (2013.01); B62D 5/063 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A steering device comprising:
a steering mechanism including a steering shaft, and a transmitting mechanism,
the steering shaft including a first shaft, a second shaft, and a torsion bar provided between the first shaft and the second shaft, and
the transmitting mechanism configured to transmit a rotation of the steering shaft to a steered wheel;
a power cylinder including a power cylinder main body portion, a piston, and a first hydraulic chamber, and a second hydraulic chamber,
the power cylinder configured to provide a steering force for steering the steered wheel, to the transmitting mechanism, and
the piston which is provided within the power cylinder main body portion, and which separates an inside space of the power cylinder main body portion into the first hydraulic chamber and the second hydraulic chamber;
a first electric motor which includes a stator coil, and a motor rotor, and which is configured to provide a rotation force to the first shaft;
a first pump configured to be driven by a first driving source, and to discharge a hydraulic fluid;
a second pump configured to be driven by a second electric motor which is a second driving source, and to discharge the hydraulic fluid;
a rotary valve configured to selectively supply the hydraulic fluid supplied from the first pump or the second pump, to the first hydraulic chamber and the second hydraulic chamber in accordance with a torsion of the torsion bar; and
a controller including a first hydraulic passage state judging section, a first electric motor control section, and a second electric motor control section;
the first hydraulic passage state judging section configured to judge a state of the hydraulic fluid in a first hydraulic passage in which the hydraulic fluid discharged from the first pump flows,
the first electric motor control section configured to:
control and drive the first electric motor based on a driving state of a vehicle,
receive input of a rotation speed of the second electric motor, and
control and drive the first electric motor in accordance with the rotation speed of the second electric motor, and
the second electric motor control section configured to increase a rotation number of the second electric motor when the first hydraulic passage state judging section judges that a supply of the hydraulic fluid in the first hydraulic passage is deficient.