Patents by Inventor Kohei NAGAO

Kohei NAGAO 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: 12168859
    Abstract: A working machine includes a controller to perform an automatic deceleration operation to automatically decelerate from a second speed to a first speed when a value calculated based on a first traveling pressure, a second traveling pressure, a third traveling pressure, and a fourth traveling pressure becomes equal to or more than a deceleration threshold in a state where a left traveling motor and a right traveling motor are being driven at the second speed.
    Type: Grant
    Filed: June 25, 2021
    Date of Patent: December 17, 2024
    Assignee: KUBOTA CORPORATION
    Inventors: Yuji Fukuda, Kohei Nagao, Ryota Hamamoto, Hiroaki Nakagawa
  • Patent number: 12146296
    Abstract: A working machine includes a traveling motor that is shifted between a first speed and a second speed faster than the first speed, a traveling pump that supplies hydraulic fluid to the traveling motor, a traveling operation member operable to operate the traveling pump, and a controller including an automatic speed reduction unit that performs automatic speed reduction in which the traveling motor having been shifted to the second speed is automatically shifted from the second speed to the first speed based on the operation amount of the traveling operation member. The controller includes an automatic speed reduction restraining unit configured or programmed to restrain the automatic speed reduction from being performed when the traveling operation member is operated to steeply change the operation amount from a first operation amount to a second operation amount.
    Type: Grant
    Filed: December 14, 2021
    Date of Patent: November 19, 2024
    Assignee: KUBOTA CORPORATION
    Inventors: Kohei Nagao, Yuji Fukuda
  • Patent number: 12139888
    Abstract: A working machine includes a machine body, a traveling device provided on the machine body, an operation member operable to activate the traveling device, a camera device to capture an image of surroundings of the machine body, a display unit to display the image captured by the camera device, a notification unit to notify a traveling direction of the traveling device, and a controller to control the display unit and the notification unit so that when the operation member is operated to activate the traveling device, the display unit is controlled to display the captured image and the notification unit is controlled to notify the traveling direction. The controller delays either one of a first timing when the display unit starts to display the captured image and a second timing when the notification unit starts to notify the traveling direction later than the other.
    Type: Grant
    Filed: June 25, 2021
    Date of Patent: November 12, 2024
    Assignee: KUBOTA CORPORATION
    Inventors: Yuji Fukuda, Kohei Nagao, Ryota Hamamoto, Tomoyuki Noguchi
  • Patent number: 12134877
    Abstract: A working machine includes a machine body, a left traveling device located left on the machine body, a right traveling device located right on the machine body, and a controller configured or programmed to perform automatic deceleration to automatically reduce a first rotation speed of a left traveling motor and a second rotation speed of a right traveling motor by shifting a speed stage of each of the left and right traveling motors from a second speed stage to a first speed stage that is lower than the second speed stage. The controller is configured or programmed to: not perform the automatic deceleration when the first rotation speed or the second rotation speed is equal to or higher than a predetermined rotation speed; and perform the automatic deceleration when the first rotation speed and the second rotation speed are less than the predetermined rotation speed.
    Type: Grant
    Filed: December 6, 2023
    Date of Patent: November 5, 2024
    Assignee: KUBOTA CORPORATION
    Inventors: Yuji Fukuda, Kohei Nagao
  • Publication number: 20240336301
    Abstract: A working machine includes a first rotation detector to detect a first rotation speed of the left traveling motor, a second rotation detector to detect a second rotation speed of the right traveling motor, and a controller to perform automatic deceleration to automatically reduce the first rotation speed and the second rotation speed both set at respective second speed stages by shifting a speed stage of each of the first rotation speed and the second rotation speed to a first speed stage that is lower than the second speed stage. During straight traveling of a machine body of the working machine, the controller determines a straight-traveling threshold serving as a deceleration threshold for judging whether to perform the automatic deceleration based on the first rotation speed or the second rotation speed.
    Type: Application
    Filed: June 20, 2024
    Publication date: October 10, 2024
    Applicant: KUBOTA CORPORATION
    Inventors: Yuji FUKUDA, Kohei NAGAO
  • Publication number: 20240337092
    Abstract: A working machine includes a controller to: select one of pieces of operation characteristics information corresponding to respective work attachments stored in a memory that corresponds to a work attachment attached to an attachment mount portion and fluidly connected to a hydraulic fluid port; and control, based on the selected one of the pieces of operation characteristics information, the speed of switching of a work-attachment-drive control valve when starting the work attachment and/or when stopping the work attachment.
    Type: Application
    Filed: April 6, 2023
    Publication date: October 10, 2024
    Applicant: KUBOTA CORPORATION
    Inventors: Ryota HAMAMOTO, Yuji FUKUDA, Tomoyuki NOGUCHI, Kohei NAGAO
  • Patent number: 12098524
    Abstract: A working machine includes a prime mover, a traveling device, a traveling motor, a traveling pump, a circulation fluid passage, a traveling switching valve shiftable between a first state corresponding to a first speed of a hydraulic motor and a second state corresponding to a second speed of the hydraulic motor, a brake, an actuation valve configured to output the hydraulic pressure applied to the traveling pump, and change the hydraulic pressure output therefrom, and a controller configured or programmed to control the traveling switching valve, the brake and the actuation valve, and being capable of activating a first mode. The controller is configured or programmed to, when activating the first mode, shift the brake into a braking state, shift the traveling switching valve into the second state, and control the actuation valve so as to set the hydraulic pressure output from the actuation valve to a predetermined pressure.
    Type: Grant
    Filed: September 29, 2023
    Date of Patent: September 24, 2024
    Assignee: KUBOTA CORPORATION
    Inventors: Yuji Fukuda, Kohei Nagao, Hiroaki Nakagawa, Ryota Hamamoto
  • Publication number: 20240301651
    Abstract: A working machine includes: at least one support member connectable to a work attachment to do work by making contact with an object to be contacted; at least one hydraulic cylinder to move the work attachment connected to the at least one support member, a rod-side pressure detector to detect a rod-side hydraulic pressure of hydraulic fluid in communication with a rod-side fluid chamber of the at least one hydraulic cylinder; a bottom-side pressure detector to detect a bottom-side hydraulic pressure of hydraulic fluid in communication with a bottom-side fluid chamber of the at least one hydraulic cylinder; and a controller to calculate a relationship in pressure between the rod-side hydraulic pressure and the bottom-side hydraulic pressure and evaluate, based on the calculated relationship in pressure, a contact state which is a state of contact of the work attachment with the object.
    Type: Application
    Filed: March 9, 2023
    Publication date: September 12, 2024
    Applicant: KUBOTA CORPORATION
    Inventors: Kohei NAGAO, Yuji FUKUDA
  • Patent number: 12065191
    Abstract: A working machine includes a first rotation detector to detect a first rotation speed of the left traveling motor, a second rotation detector to detect a second rotation speed of the right traveling motor, and a controller to perform automatic deceleration to automatically reduce the first rotation speed and the second rotation speed both set at respective second speed stages by shifting a speed stage of each of the first rotation speed and the second rotation speed to a first speed stage that is lower than the second speed stage. During straight traveling of a machine body of the working machine, the controller determines a straight-traveling threshold serving as a deceleration threshold for judging whether to perform the automatic deceleration based on the first rotation speed or the second rotation speed.
    Type: Grant
    Filed: June 24, 2021
    Date of Patent: August 20, 2024
    Assignee: KUBOTA CORPORATION
    Inventors: Yuji Fukuda, Kohei Nagao
  • Publication number: 20240151004
    Abstract: In a working machine, a controller is configured or programmed to control actuation of a blocking switching valve and a solenoid valve, to cause the blocking switching valve to unblock a first pilot fluid passage to perform switching to a first operation pattern in which an operation device operates a first device via a first control valve and a first hydraulic actuator, and cause the blocking switching valve to block a second pilot fluid passage and control the solenoid valve based on pilot pressure detected by a pressure detector to perform switching to a second operation pattern in which the operation device operates a second device via a second control valve and a second hydraulic actuator.
    Type: Application
    Filed: January 5, 2024
    Publication date: May 9, 2024
    Inventors: Kohei NAGAO, Yuji FUKUDA
  • Patent number: 11946227
    Abstract: A working machine includes a controller configured or programmed to perform an automatic deceleration for automatically decelerating a left traveling motor and a right traveling motor rotated at a second speed by shifting from the second speed to the first speed, and to determine a deceleration threshold that is used for judging whether the automatic deceleration has to be performed or not.
    Type: Grant
    Filed: June 28, 2021
    Date of Patent: April 2, 2024
    Assignee: KUBOTA CORPORATION
    Inventors: Kohei Nagao, Yuji Fukuda, Ryota Hamamoto, Hiroaki Nakagawa
  • Publication number: 20240102265
    Abstract: A working machine includes a machine body, a left traveling device located left on the machine body, a right traveling device located right on the machine body, and a controller configured or programmed to perform automatic deceleration to automatically reduce a first rotation speed of a left traveling motor and a second rotation speed of a right traveling motor by shifting a speed stage of each of the left and right traveling motors from a second speed stage to a first speed stage that is lower than the second speed stage. The controller is configured or programmed to: not perform the automatic deceleration when the first rotation speed or the second rotation speed is equal to or higher than a predetermined rotation speed; and perform the automatic deceleration when the first rotation speed and the second rotation speed are less than the predetermined rotation speed.
    Type: Application
    Filed: December 6, 2023
    Publication date: March 28, 2024
    Applicant: KUBOTA CORPORATION
    Inventors: Yuji FUKUDA, Kohei NAGAO
  • Publication number: 20240060274
    Abstract: A speed control method for a work vehicle, includes driving an engine to rotate a first hydraulic pump provided in the work vehicle. Hydraulic fluid from the first hydraulic pump is supplied to a first hydraulic motor to rotate the first hydraulic motor to drive a first traveling device provided in a vehicle body of the work vehicle. A rotational speed of the first hydraulic motor is detected. Feedback control with respect to the engine and a control valve configured to control a pilot pressure of the first hydraulic pump is performed. The feedback control being performed to reduce a speed difference between the rotational speed detected and a target rotational speed of the first hydraulic motor corresponding to a target vehicle speed. A feedback gain of the feedback control is set based on a first coefficient which becomes larger as the target rotational speed becomes lower.
    Type: Application
    Filed: August 8, 2023
    Publication date: February 22, 2024
    Applicant: KUBOTA CORPORATION
    Inventors: Kohei NAGAO, Ryota HAMAMOTO
  • Publication number: 20240060272
    Abstract: A speed control method for a work vehicle includes controlling a first hydraulic pump to supply hydraulic fluid to a first hydraulic motor to drive a first traveling device provided on a vehicle body of the work vehicle and detecting a first differential pressure of the first hydraulic motor. The method includes regulating at least one of a first pump pilot pressure applied to a first pump pilot port of the first hydraulic pump and a rotational speed of an engine to drive the first hydraulic pump such that a vehicle speed is controlled to maintain a predetermined target speed in response to an absolute value of the first differential pressure.
    Type: Application
    Filed: August 1, 2023
    Publication date: February 22, 2024
    Applicant: KUBOTA CORPORATION
    Inventors: Kohei NAGAO, Ryota HAMAMOTO
  • Publication number: 20240052598
    Abstract: A work vehicle includes a primary pressure control valve configured to control a pilot primary pressure of pilot oil. A secondary pressure control valve is configured to control a pilot secondary pressure of the pilot oil. Control circuitry is configured to control a rotation speed of an engine according to a target rotation speed. The control circuitry is configured to control the primary pressure control valve and the secondary pressure control valve based on a first target value of the pilot primary pressure and a second target value of the pilot secondary pressure. The control circuitry is configured to reduce the first target value and the second target value such that the second target value is higher than the first target value when the rotation speed of the engine detected by a rotation speed sensor becomes lower than the target rotation speed by a predetermined speed difference or more.
    Type: Application
    Filed: August 1, 2023
    Publication date: February 15, 2024
    Applicant: KUBOTA CORPORATION
    Inventors: Kohei NAGAO, Daiki ABE, Ryota HAMAMOTO
  • Publication number: 20240052597
    Abstract: A hydraulic system for a working machine includes first and second hydraulic actuators actuated by hydraulic fluid delivered by a hydraulic pump, a first flow rate controller to control a first supply flow rate of hydraulic fluid supplied to the first hydraulic actuator to match a first required flow rate, a second flow rate controller to control a second supply flow rate of hydraulic fluid supplied to the second hydraulic actuator to match a second required flow rate, and a special flow rate control system to, if a sum of the first and second required flow rates is greater than a maximum delivery flow rate of the hydraulic pump, reduce the first supply flow rate to allow the second supply flow rate to approach the second required flow rate.
    Type: Application
    Filed: August 9, 2023
    Publication date: February 15, 2024
    Inventors: Kohei NAGAO, Yuji FUKUDA, Ryuki NISHIMOTO
  • Patent number: 11898327
    Abstract: A hydraulic system for a working machine includes a hydraulic pump to output a hydraulic fluid, an operation device operable to supply a pilot fluid in accordance with an amount by which the operation device is operated, a hydraulic actuator to be operated by the hydraulic fluid, a pilot fluid passage connected to the operation device, a first control valve connected to the pilot fluid passage and to be operated by the pilot fluid to control a flow of the hydraulic fluid, a second control valve to be operated by the pilot fluid to control a flow of the hydraulic fluid, a proportional valve to change a pressure of the pilot fluid to operate the second control valve, a pressure detector provided in the pilot fluid passage to detect a pressure in the pilot fluid passage, and a controller to control the proportional valve based on the pressure.
    Type: Grant
    Filed: June 10, 2022
    Date of Patent: February 13, 2024
    Assignee: KUBOTA CORPORATION
    Inventors: Kohei Nagao, Yuji Fukuda
  • Publication number: 20240026648
    Abstract: A working machine includes a prime mover, a traveling device, a traveling motor, a traveling pump, a circulation fluid passage, a traveling switching valve shiftable between a first state corresponding to a first speed of a hydraulic motor and a second state corresponding to a second speed of the hydraulic motor, a brake, an actuation valve configured to output the hydraulic pressure applied to the traveling pump, and change the hydraulic pressure output therefrom, and a controller configured or programmed to control the traveling switching valve, the brake and the actuation valve, and being capable of activating a first mode. The controller is configured or programmed to, when activating the first mode, shift the brake into a braking state, shift the traveling switching valve into the second state, and control the actuation valve so as to set the hydraulic pressure output from the actuation valve to a predetermined pressure.
    Type: Application
    Filed: September 29, 2023
    Publication date: January 25, 2024
    Applicant: KUBOTA CORPORATION
    Inventors: Yuji FUKUDA, Kohei NAGAO, Hiroaki NAKAGAWA, Ryota HAMAMOTO
  • Patent number: 11873624
    Abstract: A working machine includes a controller to perform automatic deceleration to automatically reduce a first rotation speed of a left traveling motor to output a power to a left traveling device on a left portion of a machine body and a second rotation speed of a right traveling motor to output a power to a right traveling device on a right portion of the machine body by shifting a speed stage of each of the left and right traveling motors from a second speed to a first speed that is lower than the second speed. The controller is configured or programmed to determine, based on the second rotation speed, a left threshold for judging whether to perform the automatic deceleration in left pivot turn of the machine body, and to determine, based on the first rotation speed, a right threshold for judging whether to perform the automatic deceleration in right pivot turn of the machine body.
    Type: Grant
    Filed: July 29, 2021
    Date of Patent: January 16, 2024
    Assignee: KUBOTA CORPORATION
    Inventors: Yuji Fukuda, Kohei Nagao
  • Patent number: 11846087
    Abstract: A working machine includes a controller configured to determine a first deceleration threshold corresponding to each of a first traveling pressure, a second traveling pressure, a third traveling pressure, and a fourth traveling pressure, to perform automatic deceleration to reduce rotation speeds of a left traveling motor and a right traveling motor, and to judge whether to perform the automatic deceleration based on the determined first deceleration threshold, the first traveling pressure, the second traveling pressure, the third traveling pressure, and the fourth traveling pressure.
    Type: Grant
    Filed: July 29, 2021
    Date of Patent: December 19, 2023
    Assignee: KUBOTA CORPORATION
    Inventors: Yuji Fukuda, Kohei Nagao, Ryota Hamamoto, Hiroaki Nakagawa, Jun Tomita