Patents by Inventor Akira Sawada

Akira Sawada has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11912136
    Abstract: A control method of an electric vehicle using one or a plurality of motors as a traveling drive source, includes: a motor torque command value calculating step that calculates a motor torque command value; an angular velocity detecting step that detects an angular velocity correlating with a rotation speed of a drive shaft which transmits a drive force of the motor to a drive wheel; a disturbance torque estimating step that estimates a disturbance torque acting on the motor based on the motor torque command value and the angular velocity; a limiting torque setting step that sets a limiting torque corresponding to the disturbance torque in a manner that a slipping rate of the drive wheel does not exceed a first predetermined value; and a motor torque limiting step that limits the motor torque command value using the limiting torque.
    Type: Grant
    Filed: March 6, 2020
    Date of Patent: February 27, 2024
    Assignee: NISSAN MOTOR CO., LTD.
    Inventor: Akira Sawada
  • Patent number: 11801757
    Abstract: A control method for an electric vehicle in which a motor is used as a traveling drive source and deceleration is performed by a regenerative braking force of the motor, the electric vehicle including a towing unit configured to tow a separate object, the method including: acquiring an accelerator operation amount; acquiring a total mass of the electric vehicle; estimating a disturbance torque acting on the electric vehicle; acquiring an angular velocity of a rotary body; estimating a vehicle body speed of the electric vehicle; calculating a torque command value for the motor; measuring a load applied to the towing unit; correcting the total mass of the electric vehicle based on the measured load applied to the towing unit and the torque command value; controlling a torque generated in the motor based on the torque command value; and converging the torque command value to the disturbance torque.
    Type: Grant
    Filed: March 27, 2019
    Date of Patent: October 31, 2023
    Assignee: NISSAN MOTOR CO., LTD.
    Inventors: Akira Sawada, Takashi Nakajima, Kengo Fujiwara, Shou Oono, Yui Ito
  • Publication number: 20230286392
    Abstract: A control method of an electric vehicle using one or a plurality of motors as a traveling drive source, includes: a motor torque command value calculating step that calculates a motor torque command value; an angular velocity detecting step that detects an angular velocity correlating with a rotation speed of a drive shaft which transmits a drive force of the motor to a drive wheel; a disturbance torque estimating step that estimates a disturbance torque acting on the motor based on the motor torque command value and the angular velocity; a limiting torque setting step that sets a limiting torque corresponding to the disturbance torque in a manner that a slipping rate of the drive wheel does not exceed a first predetermined value; and a motor torque limiting step that limits the motor torque command value using the limiting torque.
    Type: Application
    Filed: March 6, 2020
    Publication date: September 14, 2023
    Applicant: NISSAN MOTOR CO., LTD.
    Inventor: Akira SAWADA
  • Publication number: 20230249558
    Abstract: An electric vehicle control method for controlling a motor based on a torque command value in an electric vehicle includes: a disturbance torque estimation process of calculating a disturbance torque estimation value including an influence of a road surface gradient; a speed parameter acquisition process of acquiring a speed parameter relating to a vehicle speed; and a vehicle state control including a stop process of calculating a stopping basis torque target value so as to converge the torque command value to the disturbance torque estimation value in accordance with a decrease in the speed parameter, and a vibration damping process of calculating a stopping correction torque target value by performing filtering on the stopping basis torque target value.
    Type: Application
    Filed: April 14, 2023
    Publication date: August 10, 2023
    Applicant: NISSAN MOTOR CO., LTD.
    Inventors: Hiroyuki KOMATSU, Jun MOTOSUGI, Akira SAWADA, Yui ITO
  • Patent number: 11654778
    Abstract: Provided is an electric vehicle control method. The electric vehicle control method includes: a disturbance torque estimation process of calculating a disturbance torque estimation value including an influence of a road surface gradient; a speed parameter acquisition process of acquiring a speed parameter relating to a vehicle speed; a stop process of calculating a stopping basis torque target value so as to converge a torque command value to the disturbance torque estimation value in accordance with a decrease of a speed parameter; and a vibration damping process of calculating a stopping correction torque target value by performing filterring on the stopping basis torque target value.
    Type: Grant
    Filed: March 6, 2020
    Date of Patent: May 23, 2023
    Assignee: NISSAN MOTOR CO., LTD.
    Inventors: Hiroyuki Komatsu, Jun Motosugi, Akira Sawada, Yui Ito
  • Publication number: 20220379732
    Abstract: A control method for an electric vehicle using a motor as a traveling drive source to decelerate by a regenerative braking force of the motor, including: obtaining an accelerator operation amount; estimating a disturbance torque acting on a vehicle body of the electric vehicle; obtaining an angular velocity of a rotating body that correlates to a rotation speed of a drive shaft which drives the electric vehicle; calculating a first torque command value based on the accelerator operation amount; setting the first torque command value to a torque command value; controlling a torque generated in the motor based on the torque command value; setting a target stop position at the time of stopping the electric vehicle; calculating a target angular velocity of the rotating body according to a distance from the electric vehicle to the target stop position; calculating a second torque command value for stopping the electric vehicle at the target stop position based on a difference between the target angular velocity an
    Type: Application
    Filed: October 28, 2019
    Publication date: December 1, 2022
    Applicant: NISSAN MOTOR CO., LTD.
    Inventors: Katsunori NAKAMURA, Akira SAWADA, Takashi NAKAJIMA, Kengo FUJIWARA
  • Publication number: 20220258617
    Abstract: Provided is an electric vehicle control method. The electric vehicle control method includes: a disturbance torque estimation process of calculating a disturbance torque estimation value including an influence of a road surface gradient; a speed parameter acquisition process of acquiring a speed parameter relating to a vehicle speed; a stop process of calculating a stopping basis torque target value so as to converge a torque command value to the disturbance torque estimation value in accordance with a decrease of a speed parameter; and a vibration damping process of calculating a stopping correction torque target value by performing filterring on the stopping basis torque target value.
    Type: Application
    Filed: March 6, 2020
    Publication date: August 18, 2022
    Applicant: NISSAN MOTOR CO., LTD.
    Inventors: Hiroyuki KOMATSU, Jun MOTOSUGI, Akira SAWADA, Yui ITO
  • Publication number: 20220185121
    Abstract: A control method for an electric vehicle according to the present embodiment is a control method for an electric vehicle in which an electric motor 4 is used as a traveling drive source and deceleration is performed by a regenerative braking force of the electric motor 4.
    Type: Application
    Filed: March 27, 2019
    Publication date: June 16, 2022
    Applicant: NISSAN MOTOR CO., LTD.
    Inventors: Akira SAWADA, Takashi NAKAJIMA, Kengo FUJIWARA, Shou OONO, YUI ITO
  • Patent number: 11050952
    Abstract: A reading circuit for an infrared detector, includes: pixel driving circuits arranged in a matrix; vertical selection lines provided for respective rows of the pixel driving circuits; horizontal selection lines provided for respective columns of the pixel driving circuits; a vertical selection circuit configured to output a row selection signal to the vertical selection lines; and a horizontal selection circuit configured to output a column selection signal to the horizontal selection lines to read, to a reading line, a signal from pixel driving circuits for one row selected by the row selection signal, wherein each pixel driving circuit includes a driving circuit of the infrared detector, and a switching circuit configured to switch whether or not to input a test signal to the driving circuit, based on the row selection signal output to a corresponding vertical selection line and the column selection signal output to a corresponding horizontal selection line.
    Type: Grant
    Filed: October 11, 2019
    Date of Patent: June 29, 2021
    Assignee: FUJITSU LIMITED
    Inventor: Akira Sawada
  • Patent number: 10994619
    Abstract: A control method for an electric vehicle includes controlling a torque of a motor based on a final torque command value by calculating the final torque command value such that a vibration damping control to reduce vibrations of a driving force transmission system of a vehicle is performed on a target torque command value set based on vehicle information, calculating the final torque command value based on the target torque command value and a value obtained by multiplying a drive-shaft torsional angular velocity by a feedback gain, estimating, by use of a vehicle model that models the driving force transmission system, a dead-zone period during which a motor torque output from the motor is not transmitted to a drive-shaft torque of the vehicle, and determining whether or not the vehicle is just before stop of the vehicle.
    Type: Grant
    Filed: December 14, 2016
    Date of Patent: May 4, 2021
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Akira Sawada, Kengo Fujiwara, Shou Oono
  • Patent number: 10972020
    Abstract: The control method for an electric vehicle sets a motor torque command value based on vehicle information and controls torque of a first motor connected to a first drive wheel which is one of a front drive wheel and a rear drive wheel. The control method for an electric vehicle calculates a first torque command value by a feedforward computation based on the motor torque command value, detects a rotation angular velocity of the first motor, and estimates a rotation angular velocity of the first motor based on the first torque command value by using a vehicle model Gp(s) that simulates a transfer characteristic from a torque input to the first drive wheel to a rotation angular velocity of the first motor.
    Type: Grant
    Filed: June 1, 2017
    Date of Patent: April 6, 2021
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Akira Sawada, Ken Itou, Kengo Fujiwara
  • Publication number: 20200259431
    Abstract: The control method for an electric vehicle sets a motor torque command value based on vehicle information and controls torque of a first motor connected to a first drive wheel which is one of a front drive wheel and a rear drive wheel. The control method for an electric vehicle calculates a first torque command value by a feedforward computation based on the motor torque command value, detects a rotation angular velocity of the first motor, and estimates a rotation angular velocity of the first motor based on the first torque command value by using a vehicle model Gp(s) that simulates a transfer characteristic from a torque input to the first drive wheel to a rotation angular velocity of the first motor.
    Type: Application
    Filed: June 1, 2017
    Publication date: August 13, 2020
    Applicant: Nissan Motor Co., Ltd.
    Inventors: Akira Sawada, Ken Itou, Kengo Fujiwara
  • Patent number: 10710463
    Abstract: The control device for the electric vehicle determines whether or not the starting operation of the vehicle has been performed by the driver, calculates the disturbance torque estimated value Td necessary for maintaining the vehicle stop state corresponding to the disturbance acting on the vehicle, and performs a control such that the driving torque of the motor converges to the disturbance torque estimated value Td when the vehicle is determined to be just before stop of the vehicle during running or determined to have undergone the starting operation. Then, the control device for the electric vehicle controls the responsiveness of the driving torque to the disturbance acting on the vehicle, and increases the responsiveness of the driving torque of the motor compared with the responsiveness of the driving torque just before stop of the vehicle when the starting operation is determined to have been performed.
    Type: Grant
    Filed: May 26, 2015
    Date of Patent: July 14, 2020
    Assignee: NISSAN MOTOR CO., LTD.
    Inventors: Akira Sawada, Ken Itou, Takashi Nakajima, Yuji Katsumata, Hiroyuki Komatsu
  • Patent number: 10696177
    Abstract: A vehicle control device for decelerating by the regenerative braking of a motor connected to a drive shaft of a drive wheel calculates a torque command value for suppressing a vibration component of the drive shaft by feeding back a torsional angular velocity of the drive shaft to a desired torque that determines the power of the motor and controls the operation of the motor on the basis of the torque command value. The control device estimates a dead zone section, in which the torque of the motor in the vehicle is not transmitted to the drive shaft, on the basis of the desired torque and limits the torque command value in the case where the vehicle is in the dead zone section.
    Type: Grant
    Filed: July 29, 2016
    Date of Patent: June 30, 2020
    Assignee: NISSAN MOTOR CO., LTD.
    Inventors: Kengo Fujiwara, Akira Sawada, Sho Ohno
  • Publication number: 20200137323
    Abstract: A reading circuit for an infrared detector, includes: pixel driving circuits arranged in a matrix; vertical selection lines provided for respective rows of the pixel driving circuits; horizontal selection lines provided for respective columns of the pixel driving circuits; a vertical selection circuit configured to output a row selection signal to the vertical selection lines; and a horizontal selection circuit configured to output a column selection signal to the horizontal selection lines to read, to a reading line, a signal from pixel driving circuits for one row selected by the row selection signal, wherein each pixel driving circuit includes a driving circuit of the infrared detector, and a switching circuit configured to switch whether or not to input a test signal to the driving circuit, based on the row selection signal output to a corresponding vertical selection line and the column selection signal output to a corresponding horizontal selection line.
    Type: Application
    Filed: October 11, 2019
    Publication date: April 30, 2020
    Applicant: FUJITSU LIMITED
    Inventor: Akira Sawada
  • Publication number: 20190337398
    Abstract: A vehicle control device for decelerating by the regenerative braking of a motor connected to a drive shaft of a drive wheel calculates a torque command value for suppressing a vibration component of the drive shaft by feeding back a torsional angular velocity of the drive shaft to a desired torque that determines the power of the motor and controls the operation of the motor on the basis of the torque command value. The control device estimates a dead zone section, in which the torque of the motor in the vehicle is not transmitted to the drive shaft, on the basis of the desired torque and limits the torque command value in the case where the vehicle is in the dead zone section.
    Type: Application
    Filed: July 29, 2016
    Publication date: November 7, 2019
    Applicant: NISSAN MOTOR CO., LTD.
    Inventors: Kengo FUJIWARA, Akira SAWADA, Sho OHNO
  • Patent number: 10404929
    Abstract: A signal output circuit includes a transistor includes a source that is coupled to a light receiving element and a gate of which electric potential is fixed, a first switch circuit capable of fixing a potential of the source to a reference potential, a second switch circuit coupled to a drain of the transistor, a third switch circuit coupled to the drain, a first capacitor coupled to the drain via the second switch circuit and coupled to the drain via the third switch circuit, wherein a first voltage according to a first current flowing through the transistor via the second switch circuit occurs, and a second voltage according to a second current flowing through the transistor via the third switch circuit occurs, and an output circuit that outputs a first signal corresponding to the first voltage and a second signal corresponding to the second voltage.
    Type: Grant
    Filed: August 24, 2017
    Date of Patent: September 3, 2019
    Assignee: FUJITSU LIMITED
    Inventors: Hironori Nishino, Akira Sawada
  • Patent number: 10328803
    Abstract: the control device for electric vehicle in the first embodiment, in the electric vehicle including the motor that functions as the traveling driving source and provides a regenerative braking force to the vehicle, and the friction brakes that provide the friction braking force to the vehicle, detects the motor rotation speed proportionate to a running speed of this electric vehicle, estimates the disturbance torque that acts on the motor, and performs the control such that the motor torque command value converges to the disturbance torque estimated value as the motor rotation speed decreases. Then, when the motor rotation speed becomes almost 0, the control device performs the control such that the friction-braking-amount command value with respect to the friction brakes converges to a value determined on the basis of the disturbance torque estimated value, and causes the motor torque command value to converge to almost 0.
    Type: Grant
    Filed: August 10, 2016
    Date of Patent: June 25, 2019
    Assignee: NISSAN MOTOR CO., LTD.
    Inventors: Hiroyuki Komatsu, Ken Itou, Takashi Nakajima, Yuuji Katsumata, Akira Sawada
  • Patent number: 10300795
    Abstract: A regenerative braking control device of an electric vehicle, wherein, in an electric vehicle system that includes an electric motor coupled to a drive wheel, the regenerative braking control device has an electric motor controller that controls powering or regeneration of the electric motor, and a regeneration amount setting unit that sets a regeneration amount by a driver operation and that can change the regeneration amount according to an intention of a driver. The electric motor controller includes a regeneration instruction torque limitation unit that limits, immediately before stop of the vehicle with a motor rotation speed in a low-speed area, the regeneration amount to be decreased as a motor rotation speed is lowered.
    Type: Grant
    Filed: January 24, 2013
    Date of Patent: May 28, 2019
    Assignee: Nissan Motor Co., Ltd.
    Inventor: Akira Sawada
  • Patent number: 10266069
    Abstract: A control device for electric motor vehicle uses the motor as the traveling driving source. The control device for electric motor vehicle is configured to decelerate by the regenerative braking force from the motor. The control device for electric motor vehicle is configured to detect the amount of the accelerator operation, detect the motor rotation speed proportionate to the traveling speed of the electric motor vehicle, and calculate the motor rotation speed estimated value according to the state of the electric motor vehicle. Additionally, the control device for electric motor vehicle is configured to detect or estimate the resistance component unrelated to the gradient from the vehicle state and correct the motor rotation speed estimated value according to the resistance component.
    Type: Grant
    Filed: January 26, 2015
    Date of Patent: April 23, 2019
    Assignee: NISSAN MOTOR CO., LTD.
    Inventors: Akira Sawada, Ken Ito, Takashi Nakajima, Yuji Katsumata, Hiroyuki Komatsu