Patents by Inventor Yoichi Kumemura

Yoichi Kumemura 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: 10591008
    Abstract: Provided are a disc brake and a piston whose weights can be effectively reduced. A disc brake includes a piston configured to press a pad against a disc. The piston includes a body member formed into a bottomed cylindrical shape and including a cylinder portion and a bottom portion. The cylinder portion and the bottom portion are approximately equal in wall thickness. The piston further includes a plate-shaped member fixed to an external bottom surface of the body member and disposed within a range of the external bottom surface and in a region including a center of the external bottom surface.
    Type: Grant
    Filed: June 21, 2016
    Date of Patent: March 17, 2020
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Kumi Hashimoto, Yoichi Kumemura, Keisuke Taniguchi
  • Patent number: 10183657
    Abstract: A master cylinder includes a piston seal installed in a circumferential groove. The piston seal includes an annular base section, an inner circumferential lip section protruding from an inner circumferential side of the base section to come in sliding contact with an outer circumferential surface of a piston, an outer circumferential lip section protruding from an outer circumferential side of the base section to abut the circumferential groove, and an intermediate protrusion section protruding from between the inner circumferential lip section and the outer circumferential lip section of the base section to a forward side of the outer circumferential lip section. A step difference section is formed at the outer circumferential side. The circumferential groove has a step section that always abuts an outer circumferential surface of the step difference section.
    Type: Grant
    Filed: January 29, 2014
    Date of Patent: January 22, 2019
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Sadatomo Matsumura, Yoichi Kumemura
  • Publication number: 20180245648
    Abstract: Provided are a disc brake and a piston whose weights can be effectively reduced. A disc brake includes a piston configured to press a pad against a disc. The piston includes a body member formed into a bottomed cylindrical shape and including a cylinder portion and a bottom portion. The cylinder portion and the bottom portion are approximately equal in wall thickness. The piston further includes a plate-shaped member fixed to an external bottom surface of the body member and disposed within a range of the external bottom surface and in a region including a center of the external bottom surface.
    Type: Application
    Filed: June 21, 2016
    Publication date: August 30, 2018
    Inventors: Kumi HASHIMOTO, Yoichi KUMEMURA, Keisuke TANIGUCHI
  • Patent number: 9797464
    Abstract: An urging spring (15) urges a friction pad toward the exit side of the rotational direction of a disk when a vehicle equipped with the disk brake runs forward. The urging spring is disposed between a lug portion (11A) of the friction pad and a torque receiving surface (5) of a carrier (2). The distal end of the urging spring is configured to abut against the disk to perform wear detection. The urging spring includes a mounting portion (15A), a first extending portion (15B), a boundary region (15E), a bent portion (15C), and a second extending portion (15D). The boundary region is reduced in width to lower stiffness. The bent portion is increased in width and provided with reinforcing portions, thereby enhancing the stiffness. Thus, the natural frequencies of the second extending portion in the rotational direction K and the vertical direction J come close to each other.
    Type: Grant
    Filed: April 30, 2014
    Date of Patent: October 24, 2017
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Hayuru Inoue, Daisuke Tanabe, Yoichi Kumemura, Seiko Tanabe, Hitoshi Yoshida
  • Patent number: 9663085
    Abstract: A circumferential wall of a circumferential groove near a bottom section of a cylinder main body has an outer wall section extending from a bottom section of the circumferential groove in a radial direction of the cylinder main body, a stepped surface section extending from the outer wall section in a bottom direction of the cylinder main body, and an inner wall section having a flat surface section parallel to the radial direction of the cylinder main body and formed further inside in the radial direction of the cylinder main body than the stepped surface section. The inner wall section is formed at a position at which the center lip section first abuts the inner wall section prior to the outer wall section when the seal member moves toward the bottom section of the cylinder main body.
    Type: Grant
    Filed: March 27, 2013
    Date of Patent: May 30, 2017
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Seiko Tanabe, Yoichi Kumemura
  • Patent number: 9360068
    Abstract: A disc brake that suppresses braking noises when a vehicle moves backward include an urging spring urging a friction pad toward a rotationally exiting side of a disc when the vehicle moves forward, the urging spring being arranged between a hook portion of the friction pad and a torque receiving portion of a carrier. The urging spring formed through bend of an elastic plate material has its spring constant that is set to be a small value to avoid resonance frequency causing noise where the base end side thereof is fixed to the hook portion of the backing plate while the top end side thereof elastically abuts to the torque receiving portion of the carrier. The urging spring is located at the position that is outside in the radial direction from the center position of the hook portion in its width direction.
    Type: Grant
    Filed: June 29, 2010
    Date of Patent: June 7, 2016
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Shoichi Noguchi, Daisuke Tanabe, Takeshi Fujiki, Koichi Masuko, Shigeru Hayashi, Koji Fukui, Yoichi Kumemura, Hayuru Inoue, Seiko Tsubota
  • Publication number: 20160116011
    Abstract: An urging spring (15) urges a friction pad toward the exit side of the rotational direction of a disk when a vehicle equipped with the disk brake runs forward. The urging spring is disposed between a lug portion (11A) of the friction pad and a torque receiving surface (5) of a carrier (2). The distal end of the urging spring is configured to abut against the disk to perform wear detection. The urging spring includes a mounting portion (15A), a first extending portion (15B), a boundary region (15E), a bent portion (15C), and a second extending portion (15D). The boundary region is reduced in width to lower stiffness. The bent portion is increased in width and provided with reinforcing portions, thereby enhancing the stiffness. Thus, the natural frequencies of the second extending portion in the rotational direction K and the vertical direction J come close to each other.
    Type: Application
    Filed: April 30, 2014
    Publication date: April 28, 2016
    Inventors: Hayuru INOUE, Daisuke TANABE, Yoichi KUMEMURA, Seiko TANABE, Hitoshi YOSHIDA
  • Publication number: 20150360660
    Abstract: A master cylinder includes a piston seal (45) installed in a circumferential groove (32). The piston seal (45) includes an annular base section (101), an inner circumferential lip section (102) protruding from an inner circumferential side of the base section (101) to come in sliding contact with an outer circumferential surface (18a) of a piston (18), an outer circumferential lip section (103) protruding from an outer circumferential side of the base section (101) to abut the circumferential groove (32), and an intermediate protrusion section (104) protruding from between the inner circumferential lip section (102) and the outer circumferential lip section (103) of the base section (101) to a forward side of the outer circumferential lip section (103). A step difference section (107) that is long in the axial direction at the inner circumferential side is formed at the outer circumferential side of the base section (101).
    Type: Application
    Filed: January 29, 2014
    Publication date: December 17, 2015
    Inventors: Sadatomo MATSUMURA, Yoichi KUMEMURA
  • Patent number: 9027716
    Abstract: A pressing part is provided at a disk-circumferentially central portion of a base plate member of a shim plate. The pressing part presses a friction pad at the center in the disk circumferential direction of the friction pad when a piston starts to press the friction pad. The pressing part is formed by slitting and raising the disk-circumferentially central portion of the shim plate along the disk radial direction. When the pressing force of the piston is in a low pressure range, the pressing force is transmitted to the friction pad through the pressing part. After the pressing force of the piston has exceeded the low pressure range, the pressing force is transmitted to the friction pad through the whole region in the disk circumferential direction of the piston.
    Type: Grant
    Filed: June 29, 2012
    Date of Patent: May 12, 2015
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Seiko Tanabe, Yoichi Kumemura, Hayuru Inoue, Hitoshi Yoshida
  • Publication number: 20150047338
    Abstract: A circumferential wall of a circumferential groove near a bottom section of a cylinder main body has an outer wall section extending from a bottom section of the circumferential groove in a radial direction of the cylinder main body, a stepped surface section extending from the outer wall section in a bottom direction of the cylinder main body, and an inner wall section having a flat surface section parallel to the radial direction of the cylinder main body and formed further inside in the radial direction of the cylinder main body than the stepped surface section. The inner wall section is formed at a position at which the center lip section first abuts the inner wall section prior to the outer wall section when the seal member moves toward the bottom section of the cylinder main body.
    Type: Application
    Filed: March 27, 2013
    Publication date: February 19, 2015
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Seiko Tanabe, Yoichi Kumemura
  • Patent number: 8348283
    Abstract: A suspension control apparatus selectively performs at least one of: compression-stroke control performed when a wheel load is increased, for setting a damping-force characteristic of at least one of damping-force variable dampers, which is provided on a side of at least one wheel whose wheel load is to be increased among a plurality of wheels, to a hard side in an early stage of a compression stroke and switching the damping-force characteristic to a soft side in a latter stage of the compression stroke; extension-stroke control performed when the wheel load is increased, for setting the damping-force characteristic to the soft side in an early stage of an extension stroke and switching the damping-force characteristic to the hard side in a latter stage of the extension stroke; compression-stroke control performed when the wheel load is reduced, for setting the damping-force characteristic of at least one of the damping-force variable dampers, which is provided on a side of at least one wheel whose wheel loa
    Type: Grant
    Filed: March 25, 2011
    Date of Patent: January 8, 2013
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Naofumi Harada, Yoichi Kumemura, Tatsuya Gankai
  • Publication number: 20130001025
    Abstract: A pressing part is provided at a disk-circumferentially central portion of a base plate member of a shim plate. The pressing part presses a friction pad at the center in the disk circumferential direction of the friction pad when a piston starts to press the friction pad. The pressing part is formed by slitting and raising the disk-circumferentially central portion of the shim plate along the disk radial direction. When the pressing force of the piston is in a low pressure range, the pressing force is transmitted to the friction pad through the pressing part. After the pressing force of the piston has exceeded the low pressure range, the pressing force is transmitted to the friction pad through the whole region in the disk circumferential direction of the piston.
    Type: Application
    Filed: June 29, 2012
    Publication date: January 3, 2013
    Inventors: Seiko TANABE, Yoichi KUMEMURA, Hayuru INOUE, Hitoshi YOSHIDA
  • Patent number: 8103451
    Abstract: A collision between a vehicle and an obstacle is estimated, and based on the estimation result, vehicle deceleration control is performed by a brake actuator to reduce the collision and vehicle wheel load is controlled by a suspension actuator.
    Type: Grant
    Filed: January 19, 2007
    Date of Patent: January 24, 2012
    Assignee: Hitachi, Ltd.
    Inventors: Taisetsu Tanimichi, Tatsuya Yoshida, Mikio Ueyama, Shinya Ohtsuji, Isa Ismet Khumaedi, Takahide Kobayashi, Koji Fukui, Nobuyuki Ichimaru, Yoichi Kumemura, Shuichiro Kuroiwa, Masaaki Uchiyama, Tatsuya Gankai, Ryusuke Hirao
  • Publication number: 20110241299
    Abstract: A suspension control apparatus selectively performs at least one of: compression-stroke control performed when a wheel load is increased, for setting a damping-force characteristic of at least one of damping-force variable dampers, which is provided on a side of at least one wheel whose wheel load is to be increased among a plurality of wheels, to a hard side in an early stage of a compression stroke and switching the damping-force characteristic to a soft side in a latter stage of the compression stroke; extension-stroke control performed when the wheel load is increased, for setting the damping-force characteristic to the soft side in an early stage of an extension stroke and switching the damping-force characteristic to the hard side in a latter stage of the extension stroke; compression-stroke control performed when the wheel load is reduced, for setting the damping-force characteristic of at least one of the damping-force variable dampers, which is provided on a side of at least one wheel whose wheel loa
    Type: Application
    Filed: March 25, 2011
    Publication date: October 6, 2011
    Inventors: Naofumi HARADA, Yoichi KUMEMURA, Tatsuya GANKAI
  • Publication number: 20100326777
    Abstract: A disc brake that suppresses braking noises when a vehicle moves backward include an urging spring urging a friction pad toward a rotationally exiting side of a disc when the vehicle moves forward, the urging spring being arranged between a hook portion of the friction pad and a torque receiving portion of a carrier. The urging spring formed through bend of an elastic plate material has its spring constant that is set to be a small value to avoid resonance frequency causing noise where the base end side thereof is fixed to the hook portion of the backing plate while the top end side thereof elastically abuts to the torque receiving portion of the carrier. The urging spring is located at the position that is outside in the radial direction from the center position of the hook portion in its width direction.
    Type: Application
    Filed: June 29, 2010
    Publication date: December 30, 2010
    Applicant: Hitachi Automotive Systems, Ltd.
    Inventors: Shoichi Noguchi, Daisuke Tanabe, Takeshi Fujiki, Koichi Masuko, Shigeru Hayashi, Koji Fukui, Yoichi Kumemura, Hayuru Inoue, Seiko Tsubota
  • Publication number: 20100078269
    Abstract: There is provided a disk brake, comprising: a pad supporting member where at least a pair of lining pads is supported, and at least two first installation holes are provided at a mounting portion that is installed to a vehicle; at least two second installation holes provided at a non-rotational portion of the vehicle; and a fixing bolt installed into the first and second installation holes so as to fasten the mounting portion and the non-rotational portion, wherein a reinforcement member is provided with at least two internal thread portions into which the fixing bolt is screwed, the reinforcement member being formed with materials different from the ones of the mounting portion and the non-rotational portion, and the mounting portion and the non-rotational portion are fastened by means of the reinforcement member and the fixing bolt.
    Type: Application
    Filed: September 9, 2009
    Publication date: April 1, 2010
    Applicant: Hitachi Automotive Systems, Ltd.
    Inventors: Takahiro Tokunaga, Shinji Suzuki, Yoichi Kumemura
  • Publication number: 20070192030
    Abstract: A collision between a vehicle and an obstacle is estimated, and based on the estimation result, vehicle deceleration control is performed by a brake actuator to reduce the collision and vehicle wheel load is controlled by a suspension actuator.
    Type: Application
    Filed: January 19, 2007
    Publication date: August 16, 2007
    Applicant: Hitachi, Ltd.
    Inventors: Taisetsu Tanimichi, Tatsuya Yoshida, Mikio Ueyama, Shinya Ohtsuji, Isa Ismet Khumaedi, Takahide Kobayashi, Koji Fukui, Nobuyuki Ichimaru, Yoichi Kumemura, Shuichiro Kuroiwa, Masaaki Uchiyama, Tatsuya Gankai, Ryusuke Hirao