Patents by Inventor Takamitsu Shimazu

Takamitsu Shimazu 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: 10344853
    Abstract: A hydraulic switch malfunction assessment device includes a solenoid valve disposed in a hydraulic circuit of an automatic transmission and having a characteristic such that a hydraulic pressure supplied to a frictional engagement element changes due to a change in an electric current supplied to the solenoid valve, and a hydraulic switch interposed between the solenoid valve and the frictional engagement element and configured to output an ON signal when the hydraulic pressure is higher than or equal to a threshold value and output an OFF signal when the hydraulic pressure is less than the threshold value. Also provided is a controller configured to control the supplied current to a prescribed current value or less when a predetermined running condition has been met, and then assess a malfunction of the hydraulic switch, based on a state of operation of the solenoid valve and the signal from the hydraulic switch.
    Type: Grant
    Filed: September 24, 2014
    Date of Patent: July 9, 2019
    Assignee: JATCO LTD
    Inventors: Takamitsu Shimazu, Youji Itou
  • Publication number: 20160223075
    Abstract: A hydraulic switch malfunction assessment device includes a solenoid valve disposed in a hydraulic circuit of an automatic transmission and having a characteristic such that a hydraulic pressure supplied to a frictional engagement element changes due to a change in an electric current supplied to the solenoid valve, and a hydraulic switch interposed between the solenoid valve and the frictional engagement element and configured to output an ON signal when the hydraulic pressure is higher than or equal to a threshold value and output an OFF signal when the hydraulic pressure is less than the threshold value. Also provided is a controller configured to control the supplied current to a prescribed current value or less when a predetermined running condition has been met, and then assess a malfunction of the hydraulic switch, based on a state of operation of the solenoid valve and the signal from the hydraulic switch.
    Type: Application
    Filed: September 24, 2014
    Publication date: August 4, 2016
    Applicant: JATCO Ltd
    Inventors: Takamitsu SHIMAZU, Youji ITOU
  • Patent number: 7537543
    Abstract: When a throttle is substantially fully open and startup is not underway, a CVT control unit (20) controls a speed ratio in accordance with a fully open speed change line. When the throttle is substantially fully open and startup is underway, the CVT control unit (20) controls the speed ratio in accordance with a fully open startup speed change line. When the throttle is substantially fully open, startup is underway, and the number of times the primary pulley rotation speed exceeds a belt assurance upper limit value exceeds an assurance frequency number, the CVT control unit (20) controls the speed ratio in accordance with the full throttle speed change line instead of the full throttle startup speed change line, even though the throttle is substantially fully open and vehicle startup is underway.
    Type: Grant
    Filed: November 28, 2006
    Date of Patent: May 26, 2009
    Assignee: JATCO Ltd
    Inventors: Takamitsu Shimazu, Yoshichika Hagiwara
  • Publication number: 20070203631
    Abstract: A torque control device is provided to prevent slipping of a belt of a belt type continuously variable transmission. The torque control device calculates a positive input torque inputted from an engine to a primary pulley, and calculates a negative input torque inputted from a drive wheel to the primary pulley based on the positive input torque and a speed ratio of a continuously variable section. The torque control device then restricts an output torque from the engine so that the total torque can be lower than or equal to the torque capacity of the belt when the vehicle is in a running state in which the negative input torque is likely to occur and the total torque which is the sum of the positive input torque and the negative input torque exceeds the torque capacity.
    Type: Application
    Filed: February 2, 2007
    Publication date: August 30, 2007
    Applicant: JATCO Ltd.
    Inventors: Takamitsu Shimazu, Toshiyasu Yamaguchi, Yoshichika Hagiwara
  • Publication number: 20070197323
    Abstract: A hydraulic pressure control device is provide for a belt type continuously variable transmission that appropriately controls hydraulic pressure supplied to each pulley. The hydraulic pressure control device has a positive input torque calculation section that calculates a positive input torque that is inputted to a primary pulley from an engine; a negative input torque calculation section that calculates a negative input torque based on the calculated speed ratio and the positive input torque; and a hydraulic pressure regulation section that calculates a hydraulic pressure of hydraulic fluid supplied to each pulley depending on the sum of the positive input torque and the negative input torque and controls hydraulic pressure to each the pulley to the calculated hydraulic pressure.
    Type: Application
    Filed: February 2, 2007
    Publication date: August 23, 2007
    Applicant: JATCO Ltd.
    Inventors: Takamitsu Shimazu, Yoshichika Hagiwara, Tatsuo Ochiai, Kousuke Abe
  • Publication number: 20070123385
    Abstract: When a throttle is substantially fully open and startup is not underway, a CVT control unit (20) controls a speed ratio in accordance with a fully open speed change line. When the throttle is substantially fully open and startup is underway, the CVT control unit (20) controls the speed ratio in accordance with a fully open startup speed change line. When the throttle is substantially fully open, startup is underway, and the number of times the primary pulley rotation speed exceeds a belt assurance upper limit value exceeds an assurance frequency number, the CVT control unit (20) controls the speed ratio in accordance with the full throttle speed change line instead of the full throttle startup speed change line, even though the throttle is substantially fully open and vehicle startup is underway.
    Type: Application
    Filed: November 28, 2006
    Publication date: May 31, 2007
    Inventors: Takamitsu Shimazu, Yoshichika Hagiwara