公开(公告)号：US11377141B2

公开(公告)日：2022-07-05

申请号：US17260737

申请日：2019-12-12

申请人： NSK LTD.

发明人： Tetsuya Kitazume ,  Shoya Maruyama

IPC分类号： B62D3/12 ,  B62D5/04 ,  B62D6/00

摘要： An electric power steering device including: a control rotational displacement calculation unit configured to calculate a control rotational displacement when a steering angle of the steering system is in an angular range from a maximum allowable steering angle for the steering system to a predetermined threshold steering angle; a control steering angle shifting unit configured to calculate the control rotational displacement corrected by a correction amount based on one of the steering torque and rack axial force and a sign of one of the control rotational displacement and the steering angle as a shift control steering angle; and a feedforward control unit configured to output a second current command value based on the shift control steering angle and steering velocity. An assist control is controlled with a third current command value calculated by adding the second current command value to the first current command value.

公开(公告)号：US09771097B2

公开(公告)日：2017-09-26

申请号：US15032091

申请日：2015-04-16

申请人： NSK LTD.

发明人： Tetsuya Kitazume

IPC分类号： B62D15/02 ,  B62D5/04 ,  B62D6/00

CPC分类号： B62D5/0466 ,  B62D5/0409 ,  B62D6/002 ,  B62D15/0235

摘要： An active-return control section that calculates a return control current based on a steering angle, the vehicle speed and a motor angular velocity/Gr ratio, and drives the motor by a compensated-current command value obtained by subtracting the return control current from the current command value. The active-return control section includes a base-return control current calculating section that calculates a base-return control current, a target steering velocity calculating section that calculates a target steering velocity, a return control gain calculating section that obtains a deviation between the target steering velocity and the motor angular velocity/Gr ratio and sign-processes, and calculates a return control gain by at least two among a P-control calculation, an I-control calculation and a D-control calculation, a limiter that limits a maximum value of the return control gain, and a correcting section to output the return control current by correcting the control current with output of the limiter.

公开(公告)号：US11731687B2

公开(公告)日：2023-08-22

申请号：US17917778

申请日：2022-02-14

申请人： NSK LTD.

发明人： Tetsuya Kitazume ,  Shoya Maruyama

IPC分类号： B62D5/04 ,  B62D15/02

CPC分类号： B62D5/0469 ,  B62D15/0245

摘要： A terminal position learning unit includes a first storage unit configured to store a steered position positioned farthest from a neutral position of a turning mechanism within a range of a steered position detected by a position detection unit when rotational force applied to the turning mechanism is less than or equal to a first predetermined value, a second storage unit configured to store a steered position positioned farthest from the neutral position within a range of a position to which a steered position detected by the position detection unit is shifted in a direction toward the neutral position by a second predetermined value, and a third storage unit configured to store, as a terminal position stored by the terminal position learning unit, one of the steered positions stored in the first storage unit and the second storage unit positioned farther from the neutral position than the other.

公开(公告)号：US11260902B2

公开(公告)日：2022-03-01

申请号：US17289007

申请日：2020-10-21

申请人： NSK LTD.

发明人： Toru Sakaguchi ,  Tetsuya Kitazume ,  Shoya Maruyama

IPC分类号： B62D6/00 ,  B62D15/02 ,  B62D5/04

摘要： A turning control device includes: a steering angular displacement calculation unit configured to, when a third steering angle that is either a first steering angle of a turning mechanism or a second steering angle of a steering mechanism, is in an angular range from a maximum angle to a threshold steering angle, calculate a steering angular displacement of the third steering angle with the threshold steering angle used as a reference; a steering angle correction value calculation unit configured to calculate a steering angle correction value according to at least the steering angular displacement; a steering angle correction value limiting unit configured to limit the steering angle correction value according to at least a steering state, the third steering angle, and angular velocity thereof; a corrected target steering angle calculation unit configured to correct the target steering angle of the turning mechanism with a limited steering angle correction value.

公开(公告)号：US10919567B2

公开(公告)日：2021-02-16

申请号：US16094669

申请日：2017-10-24

申请人： NSK LTD.

发明人： Tetsuya Kitazume ,  Satoshi Shimokawabe

IPC分类号： B62D5/04 ,  B62D6/10

摘要： An electric power steering apparatus that drives a motor based a current command value and assist-controls a steering system by a driving-control of the motor. The apparatus includes a handle-returning control section that calculates a target steering angular velocity by using a steering angle, the vehicle speed, the steering torque and the current command value, calculates a handle-returning control current by using a limit-target steering angular velocity which is obtained by limiting the target steering angular velocity depending on steering angular velocity, and drives the motor by a compensated current command value which is obtained by adding the handle-returning control current to the current command value.

公开(公告)号：US09821837B2

公开(公告)日：2017-11-21

申请号：US14913763

申请日：2015-05-13

申请人： NSK Ltd.

发明人： Tetsuya Kitazume

IPC分类号： B62D5/04 ,  B62D6/00

CPC分类号： B62D5/0466 ,  B62D6/00

摘要： An electric power steering apparatus including a steering wheel return control section that calculates a steering wheel return control current by a steering angle, the steering torque, the vehicle speed and a steering angle velocity, and drives the motor by a compensation current command value made by adding the steering wheel return control current to the current command value.

公开(公告)号：US11753068B2

公开(公告)日：2023-09-12

申请号：US17917822

申请日：2022-02-14

申请人： NSK LTD.

发明人： Tetsuya Kitazume

IPC分类号： B62D5/04 ,  B62D15/02

CPC分类号： B62D5/0469 ,  B62D15/0245

摘要： A turning control device includes a terminal position learning unit configured to learn a terminal position of the turning mechanism, based on a steered position of the turning mechanism detected by a position detection unit, a command value correction unit configured to, when a steered position detected by the position detecting unit is in a vicinity of a learned terminal position, correct a current command value for an actuator providing a turning mechanism with steering assist force, and a correction amount limiting unit configured to limit a correction amount of the current command value by the command value correction unit, based on a comparison result between the learned terminal position and a predetermined position and a comparison result between stroke length of the turning mechanism calculated from the learned terminal positions and a predetermined length.

公开(公告)号：US11214298B2

公开(公告)日：2022-01-04

申请号：US16068167

申请日：2018-01-15

申请人： NSK LTD.

发明人： Tetsuya Kitazume ,  Satoshi Shimokawabe

IPC分类号： B62D5/04 ,  B62D15/02 ,  B62D6/00 ,  B62D1/28

摘要： The present invention is the electric power steering apparatus that drives a motor based on the current command value and assist-controls a steering system by a driving-control of the motor, comprising: a handle-returning control section to calculate the target steering angle velocity for handle-returning based on the steering torque, the current command value, a vehicle speed, a steering angle, calculate the handle-returning control current based on a deviation between the steering angle velocity and the target steering angle velocity, and interpose a filter, which motion characteristic, in a calculation path of the target steering angle velocity, wherein the motor is driven by the corrected current command value by using the handle-returning control current.

公开(公告)号：US09637166B2

公开(公告)日：2017-05-02

申请号：US14418372

申请日：2014-02-04

申请人： NSK LTD.

发明人： Takahiro Tsubaki ,  Tetsuya Kitazume ,  Keita Yoshida

IPC分类号： B62D5/04 ,  B62D1/28 ,  B62D6/00 ,  B62D6/10 ,  B62D15/02

CPC分类号： B62D5/0463 ,  B62D1/286 ,  B62D6/002 ,  B62D6/003 ,  B62D6/10 ,  B62D15/025

摘要： Although the steering angle control of a steering wheel is performed using automatic steering control, when the steering torque is applied by the steering wheel operation of the driver, the target steering angle is corrected to become the same direction as a direction that the steering torque is applied, and the steering angle control is performed to coincide with that target steering angle. Thereby, in the case of adding together outputs of the steering angle control with respect to the corrected target steering angle and the assist control by the steering torque with a certain ratio, it is possible to make the output direction of the automatic steering control coincide with the output direction of the manual steering control, and the control outputs become hard to interfere with each other. As a result, the uncomfortable feeling given to the driver that occurs in switching the steering mode is reduced.

公开(公告)号：US09623899B2

公开(公告)日：2017-04-18

申请号：US14654628

申请日：2014-01-23

申请人： NSK LTD.

发明人： Takahiro Tsubaki ,  Tetsuya Kitazume ,  Yoshiki Ninomiya

IPC分类号： B62D6/08 ,  B62D5/04 ,  B62D6/00 ,  B62D15/02 ,  G05D1/00 ,  B62D1/28 ,  B60W50/00

CPC分类号： B62D5/0463 ,  B60W2050/007 ,  B62D1/286 ,  B62D6/002 ,  B62D6/08 ,  B62D15/025 ,  G05D1/0061 ,  G05D2201/0213

摘要： An electric power steering apparatus that detects that a driver has steered the handle by using a steering torque detected by a torque sensor, switches to the manual steering mode due to a capacity (an integrated value) corresponding to a generated torque, and does not provide an uncomfortable feeling to the driver.