Patents by Inventor Yukiaki Shimizu

Yukiaki Shimizu 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: 11332115
    Abstract: A power regeneration system of a work vehicle includes: a first generator (12) and a second generator (31) that are driven by an engine (11); a first electric circuit (C1) for supplying electric power to traveling motors (10L, 10R); a second electric circuit (C2) for supplying electric power to an auxiliary device (35); a voltage step down converter (21) providing electric power from the first electric circuit to the second electric circuit; and a controller (51) that determines whether a travel mode of the work vehicle is a powering mode or a regeneration mode in order to control driving of the voltage step down converter. If the travel mode is the regeneration mode, the controller provides the regenerative power from the first electric circuit through the voltage step down converter to the second electric circuit, in order to drive the auxiliary device with the regenerative power.
    Type: Grant
    Filed: June 4, 2018
    Date of Patent: May 17, 2022
    Assignee: HITACHI CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Shintarou Tanaka, Masatsugu Arai, Naoki Fukuda, Takaaki Tanaka, Yukiaki Shimizu
  • Patent number: 11173890
    Abstract: To provide a power regeneration system for a working vehicle that can effectively use a regenerative electric energy. A first electric circuit for supplying an electric power generated by the first generator to a traveling motor, a voltage detector for detecting an actual voltage of the first electric circuit, a second electric circuit for supplying an electric power generated by a second generator to an auxiliary device, a step-down device connected to the first electric circuit and the second electric circuit, and a controller are provided. The controller estimates the voltage of the first electric circuit after a predetermined time has elapsed from the present time, based on information on a traveling state of a work vehicle and the actual voltage detected by the voltage detector, and outputs a drive command to the step-down device when the estimated voltage is equal to or more than a threshold.
    Type: Grant
    Filed: February 23, 2018
    Date of Patent: November 16, 2021
    Assignee: HITACHI CONSTRUCTION MACHINERY CO., LTD.
    Inventors: Naoki Fukuda, Masatsugu Arai, Yukiaki Shimizu, Takaaki Tanaka, Shintarou Tanaka
  • Publication number: 20200180588
    Abstract: A power regeneration system of a work vehicle includes: a first generator (12) and a second generator (31) that are driven by an engine (11); a first electric circuit (C1) for supplying electric power to traveling motors (10L, 10R); a second electric circuit (C2) for supplying electric power to an auxiliary device (35); a voltage step down converter (21) providing electric power from the first electric circuit to the second electric circuit; and a controller (51) that determines whether a travel mode of the work vehicle is a powering mode or a regeneration mode in order to control driving of the voltage step down converter. If the travel mode is the regeneration mode, the controller provides the regenerative power from the first electric circuit through the voltage step down converter to the second electric circuit, in order to drive the auxiliary device with the regenerative power.
    Type: Application
    Filed: June 4, 2018
    Publication date: June 11, 2020
    Inventors: Shintarou TANAKA, Masatsugu ARAI, Naoki FUKUDA, Takaaki TANAKA, Yukiaki SHIMIZU
  • Publication number: 20200017096
    Abstract: To provide a power regeneration system for a working vehicle that can effectively use a regenerative electric energy. A first electric circuit for supplying an electric power generated by the first generator to a traveling motor, a voltage detector for detecting an actual voltage of the first electric circuit, a second electric circuit for supplying an electric power generated by a second generator to an auxiliary device, a step-down device connected to the first electric circuit and the second electric circuit, and a controller are provided. The controller estimates the voltage of the first electric circuit after a predetermined time has elapsed from the present time, based on information on a traveling state of a work vehicle and the actual voltage detected by the voltage detector, and outputs a drive command to the step-down device when the estimated voltage is equal to or more than a threshold.
    Type: Application
    Filed: February 23, 2018
    Publication date: January 16, 2020
    Inventors: Naoki FUKUDA, Masatsugu ARAI, Yukiaki SHIMIZU, Takaaki TANAKA, Shintarou TANAKA
  • Publication number: 20140167554
    Abstract: A squirrel cage rotor includes: a rotor core having a plurality of slots formed in a circumferential direction, each slot extending in an axial direction; a plurality of conductive bars housed within the respective slots of the rotor core and having both ends thereof projecting out from end faces in an axial direction of the rotor core; and a pair of end rings disposed at both ends of the rotor core, each end ring having a plurality of fitting portions into which respective end portions of the conductive bar projecting out from the end faces of the rotor core in the axial direction are fitted. A material of the conductive bar is an aluminum alloy having an aluminum component ratio of 99.00% or more, and a material of the end ring is an aluminum alloy having proof stress higher than that of the material of the conductive bar.
    Type: Application
    Filed: August 8, 2012
    Publication date: June 19, 2014
    Applicant: Hitachi Automotive Systems, Ltd.
    Inventors: Manabu Oshida, Yukiaki Shimizu, Hiroshi Hamano, Keiji Oda
  • Patent number: 4593625
    Abstract: A vehicle bogie which includes a pair of mechanical bearings mounted on shafts of wheel assemblies and U-shaped beam surrounding the shafts and bridging the pairs of mechanical bearings. A linear induction motor is suspended from the beams, with the linear induction motor being coupled to the beams by a universal joint with the shafts being permitted to move in horizontal and vertical planes.
    Type: Grant
    Filed: August 9, 1983
    Date of Patent: June 10, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Yukiaki Shimizu, Kei Oouchi