Patents by Inventor Keisuke NAITOU

Keisuke NAITOU 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: 11905682
    Abstract: Provided is a wheel loader capable of automatically decreasing vehicle speed without making an operator feel discomfort during a loading operation. A wheel loader 1 mounted with a torque converter type traveling drive system comprises a controller 5 configured to control shifting of a transmission 32. When a vehicle body travels forward at vehicle speed corresponding to a second speed stage set greater by one speed stage than the lowest speed stage of the transmission 32 while operating the lift arm 21 upwardly, the controller 5 sets, as a gear ratio of the transmission 32, an intermediate gear ratio between a gear ratio corresponding to the second speed stage and a gear ratio corresponding to a first speed stage, and outputs a signal for selecting a combination of a plurality of gears corresponding to the set gear ratio to each first to fifth solenoid control valves 32A to 32E.
    Type: Grant
    Filed: December 25, 2019
    Date of Patent: February 20, 2024
    Assignee: HITACHI CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Tetsuji Tanaka, Masaki Nukii, Keisuke Naitou
  • Patent number: 11643792
    Abstract: Provided is a wheel loader capable of exhibiting sufficient excavation performance while suppressing slip during excavation. A control device provided on a wheel loader according to the present invention is configured to determine a reduction value (?f?) of traveling drive force based on first vehicle body acceleration (av1) of a vehicle body calculated from acceleration detected by an acceleration sensor, second vehicle body acceleration (av2) of the vehicle body calculated from rotational speed of wheels detected by a rotational speed sensor, and thrust (ph) of a hydraulic cylinder detected by a thrust sensor, and reduce the traveling drive force based on the reduction value and output the reduced traveling drive force.
    Type: Grant
    Filed: March 6, 2019
    Date of Patent: May 9, 2023
    Assignee: HITACHI CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Kazuyuki Ito, Keisuke Naitou
  • Publication number: 20230085666
    Abstract: Provided is a work vehicle capable of reducing the fuel consumption while maintaining the working efficiency. A wheel loader 1 comprising a vehicle body controller 5, 5A for controlling an engine 41, wherein the vehicle body controller 5, 5A limits an upper limit rotational speed of the engine 41 based on an accelerator pedal step-on amount ?, a brake pedal step-on amount ?, a torque converter speed ratio e which is a ratio of a rotational speed of a torque converter 42, a discharge pressure P1 of a loading hydraulic pump 44, and a stroke amount S1 of lift arm cylinders 22 or a stroke amount S2 of a bucket cylinder 24.
    Type: Application
    Filed: September 15, 2021
    Publication date: March 23, 2023
    Inventors: Takuya SHIMOMURA, Masaki YOSHIKAWA, Tetsuji TANAKA, Isamu AOKI, Kazuyuki ITO, Kouji SHIMAZAKI, Keisuke NAITOU
  • Patent number: 11167765
    Abstract: Provided is a wheel loader in which the speed position of the transmission can be easily changed with a small number of switches. The wheel loader 1 includes a tilting angle sensor 9 for detecting the tilting angle of the vehicle body. In case that the vehicle body is traveling on an uphill or a downhill with a transmission 33 in a higher speed position than the lowest speed position, and the tilting angle detected by the tilting angle sensor 9 is not smaller than a prescribed threshold value, a transmission control device 45 sends the transmission 33 a command to downshift the transmission 33 one speed position by each operation of a shiftdown switch 62.
    Type: Grant
    Filed: March 5, 2019
    Date of Patent: November 9, 2021
    Assignee: HITACHI CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Keisuke Naitou, Ryou Taniguchi
  • Publication number: 20210317637
    Abstract: Provided is a wheel loader capable of automatically decreasing vehicle speed without making an operator feel discomfort during a loading operation. A wheel loader 1 mounted with a torque converter type traveling drive system comprises a controller 5 configured to control shifting of a transmission 32. When a vehicle body travels forward at vehicle speed corresponding to a second speed stage set greater by one speed stage than the lowest speed stage of the transmission 32 while operating the lift arm 21 upwardly, the controller 5 sets, as a gear ratio of the transmission 32, an intermediate gear ratio between a gear ratio corresponding to the second speed stage and a gear ratio corresponding to a first speed stage, and outputs a signal for selecting a combination of a plurality of gears corresponding to the set gear ratio to each first to fifth solenoid control valves 32A to 32E.
    Type: Application
    Filed: December 25, 2019
    Publication date: October 14, 2021
    Inventors: Tetsuji TANAKA, Masaki NUKII, Keisuke NAITOU
  • Publication number: 20200247418
    Abstract: Provided is a wheel loader in which the speed position of the transmission can be easily changed with a small number of switches. The wheel loader 1 includes a tilting angle sensor 9 for detecting the tilting angle of the vehicle body. In case that the vehicle body is traveling on an uphill or a downhill with a transmission 33 in a higher speed position than the lowest speed position, and the tilting angle detected by the tilting angle sensor 9 is not smaller than a prescribed threshold value, a transmission control device 45 sends the transmission 33 a command to downshift the transmission 33 one speed position by each operation of a shiftdown switch 62.
    Type: Application
    Filed: March 5, 2019
    Publication date: August 6, 2020
    Inventors: Keisuke NAITOU, Ryou TANIGUCHI
  • Publication number: 20200173144
    Abstract: Provided is a wheel loader capable of exhibiting sufficient excavation performance while suppressing slip during excavation. A control device (50) provided on a wheel loader (1) according to the present invention is configured to determine a reduction value (?f?) of traveling drive force based on first vehicle body acceleration (av1) of a vehicle body calculated from acceleration detected by an acceleration sensor (31), second vehicle body acceleration (av2) of the vehicle body calculated from rotational speed of wheels (4, 8) detected by a rotational speed sensor (32), and thrust (ph) of a hydraulic cylinder (11) detected by a thrust sensor (33, 34), and reduce the traveling drive force based on the reduction value and output the reduced traveling drive force.
    Type: Application
    Filed: March 6, 2019
    Publication date: June 4, 2020
    Inventors: Kazuyuki ITO, Keisuke NAITOU
  • Patent number: 10336338
    Abstract: A work vehicle has a hydraulic source; a control valve that controls a flow of the hydraulic oil discharged from the hydraulic source; and an engine starting device for starting an engine, in which a control device has: a low-temperature state determination unit that determines whether a temperature state of a working fluid of a torque converter is a low-temperature state; and a clutch control unit that when it is determined by the low-temperature state determination unit that the temperature state of the working fluid is not the low-temperature state, controls the control valve in order to switch a lock-up clutch to a non-engagement state, and when it is determined by the low-temperature state determination unit that the temperature state of the working fluid is the low-temperature state, controls the control valve in order to switch the lock-up clutch to a engagement state.
    Type: Grant
    Filed: March 6, 2017
    Date of Patent: July 2, 2019
    Assignee: KCM Corporation
    Inventors: Atsushi Nakamura, Keisuke Naitou
  • Publication number: 20180086345
    Abstract: A work vehicle has a hydraulic source; a control valve that controls a flow of the hydraulic oil discharged from the hydraulic source; and an engine starting device for starting an engine, in which a control device has: a low-temperature state determination unit that determines whether a temperature state of a working fluid of a torque converter is a low-temperature state; and a clutch control unit that when it is determined by the low-temperature state determination unit that the temperature state of the working fluid is not the low-temperature state, controls the control valve in order to switch a lock-up clutch to a non-engagement state, and when it is determined by the low-temperature state determination unit that the temperature state of the working fluid is the low-temperature state, controls the control valve in order to switch the lock-up clutch to a engagement state.
    Type: Application
    Filed: March 6, 2017
    Publication date: March 29, 2018
    Inventors: Atsushi NAKAMURA, Keisuke NAITOU