Patents by Inventor Takamasa KOTANI

Takamasa KOTANI 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).

  • Publication number: 20240376954
    Abstract: The shock absorber includes a cylinder sealing a working fluid, a piston slidably fitted in the cylinder and partitioning an inside of the cylinder into two chambers, a rod having a first end portion fastened to the piston and a second end portion protruding from the cylinder, a passage allowing communication between one chamber and another chamber in the cylinder, a bendable plate-shaped first valve having a first support part provided in the passage and supported at one surface on a radially inner side, a second support part disposed on a radially outer side relative to the first support part and supported at one surface, and a biasing part at least a part of which is provided on a radially outer side of the second support part to bias the second support part side, and a flexible member contacting the first support part and bendable together with the first valve.
    Type: Application
    Filed: July 20, 2022
    Publication date: November 14, 2024
    Inventor: Takamasa KOTANI
  • Publication number: 20240376957
    Abstract: A damping force generation mechanism (190) includes: a biasing force generation member (91) that causes a first damping force generation member (203) having a bottomed tubular shape and disposed on a side of an opening (145) to generate a biasing force in a valve closing direction; a regulation member (18) that is provided on a side of a bottom portion (92) of the biasing force generation member (91) and includes passages (43, 44) formed to establish communication between a one-side chamber and an other-side chamber (20); a frequency sensitive mechanism (191) that is provided between the regulation member (18) and the first damping force generation member (203), is provided with a movable portion (171) in a movable manner, and makes the biasing force variable; and a seat forming member (205) that is provided at the biasing force generation member (91) on the side of the opening (145) and includes a seat (233) formed therein for the first damping force generation member (203) to be seated.
    Type: Application
    Filed: September 13, 2022
    Publication date: November 14, 2024
    Inventors: Mikio YAMASHITA, Takamasa KOTANI, Seiryo KONAKAI
  • Patent number: 12031606
    Abstract: Disclosed is a shock absorber including: a cylinder which is filled with a working fluid; a piston which is slidably provided in the cylinder and divides an inside of the cylinder into two chambers; a piston rod which is connected to the piston and extends outside the cylinder; a first passage and a second passage through which the working fluid flows due to movement of the piston; a first damping force generating mechanism which is provided in the first passage and generates a damping force; and a second damping force generating mechanism which is provided in the second passage and generates a damping force. The second damping force generating mechanism includes a sub valve provided on one side of the second passage, and a volume variable mechanism that changes a volume of a volume chamber provided in parallel with the second passage.
    Type: Grant
    Filed: March 25, 2020
    Date of Patent: July 9, 2024
    Assignee: HITACHI ASTEMO, LTD.
    Inventors: Mikio Yamashita, Takamasa Kotani
  • Publication number: 20230341023
    Abstract: A shock absorber includes a first passage provided in a piston and through which a working fluid moves from a chamber on an upstream side to a chamber on a downstream side in a cylinder due to movement of the piston, a first damping force generation mechanism provided in the first passage to generate a damping force, a second passage (141) provided in a piston rod (21), and a fixing member fixed to the piston rod (21) to form the second passage (141), and a second damping force generation mechanism provided in the second passage (141) to generate a damping force, in which a throttle member (161) provided in the second damping force generation mechanism, including a plurality of notch parts (171) at substantially regular intervals in a circumferential direction to form a throttle flow path (76) in the second passage due to the notch parts (171), and formed to have a flow path area of the throttle flow path (76) that is constant regardless of an attachment position thereof in the circumferential direction is fu
    Type: Application
    Filed: September 21, 2021
    Publication date: October 26, 2023
    Inventor: Takamasa KOTANI
  • Publication number: 20230287954
    Abstract: This shock absorber includes a first damping force generation mechanism (41) provided in a passage (92) of a piston (21), a second damping force generation mechanism (183) provided in a piston rod (25), and a fluid storage mechanism (190) provided in the piston rod (25). The fluid storage mechanism (190) includes a flexible disc (100) which deforms before the second damping force generation mechanism (183) opens, and a plate-shaped biasing member (116, 117) which has a hole portion (415) between an inner circumferential end portion and an outer circumferential end portion, and in which the inner circumferential end portion is formed so that the piston rod (25) can be inserted therein.
    Type: Application
    Filed: July 14, 2021
    Publication date: September 14, 2023
    Inventors: Mikio YAMASHITA, Takamasa KOTANI
  • Publication number: 20230279920
    Abstract: A shock absorber includes a first passage (92) through which a working fluid flows out from a chamber that is an upstream side to a chamber (23) that is a downstream side due to movement of a piston (21), a first damping force generating mechanism (41) provided in the first passage (92) to generate a damping force, a second passage (182) provided separately from the first passage (92), a second damping force generating mechanism (183) provided in the second passage (182) and opened to generate a damping force when a piston speed is lower than that of the first damping force generating mechanism (41), a third passage (512) provided separately from the second passage (182), a volume variable mechanism (186) provided in the third passage (512), a fourth passage (521) provided separately from the third passage (512), and a relief mechanism (522) provided in the fourth passage (521) and opened after the second damping force generating mechanism (183) is opened.
    Type: Application
    Filed: July 14, 2021
    Publication date: September 7, 2023
    Inventor: Takamasa KOTANI
  • Publication number: 20230272835
    Abstract: This shock absorber includes a first damping force generation mechanism provided in a passage of a piston, and a second damping force generation mechanism provided in a piston rod. The second damping force generation mechanism includes a valve seat member, a sub-valve provided in the valve seat member, and a cap member covering one end side of the second damping force generation mechanism and at least a part of an outer circumference of the valve seat member. A communication passage is formed on one end side of the cap member. A biasing member provided so that one end surface side is in contact with an outer circumferential side of the cap member with respect to the communication passage, and a bendable flexible disc provided so that the other end surface side of the biasing member is in contact therewith.
    Type: Application
    Filed: July 14, 2021
    Publication date: August 31, 2023
    Inventors: Takamasa KOTANI, Kentaro YAMADA, Mikio YAMASHITA
  • Publication number: 20220412428
    Abstract: Disclosed is a shock absorber including: a cylinder which is filled with a working fluid; a piston which is slidably provided in the cylinder and divides an inside of the cylinder into two chambers; a piston rod which is connected to the piston and extends outside the cylinder; a first passage and a second passage through which the working fluid flows due to movement of the piston; a first damping force generating mechanism which is provided in the first passage and generates a damping force; and a second damping force generating mechanism which is provided in the second passage and generates a damping force. The second damping force generating mechanism includes a sub valve provided on one side of the second passage, and a volume variable mechanism that changes a volume of a volume chamber provided in parallel with the second passage.
    Type: Application
    Filed: March 25, 2020
    Publication date: December 29, 2022
    Inventors: Mikio YAMASHITA, Takamasa KOTANI