Patents Assigned to Akebono Research and Development Centre Ltd.
  • Patent number: 5333706
    Abstract: A vehicle brake system includes a wheel shaft to which a rotor is fixedly mounted for rotation relative to a stator. Rotor coils are mounted to the rotor in close running relation with stator coils mounted by the stator. The stator also mounts a disc brake caliper and an electric actuator for pressing brake pads against surfaces of the rotor. A control circuit selectively, electrically energizes the rotor coils to produce electromagnetic braking and/or the electric actuator to produce frictional braking by the disc brake in accordance with input signals indicating the magnitude of the depression force exerted on a brake pedal, vehicle speed, and braking torque in a manner to harmonize braking action with the braking demands of the driver.
    Type: Grant
    Filed: October 16, 1992
    Date of Patent: August 2, 1994
    Assignees: Akebono Brake Industry Co., Ltd., Akebono Research and Development Centre Ltd.
    Inventor: Masatomo Mori
  • Patent number: 5305861
    Abstract: A backing plate is formed by way of a liquid metal forging process or a die-casting process by using an aluminum alloy or an aluminum-based composite material. Essential portions to which forces are applied are formed with a large thickness, and the remaining portions with a small thickness. In addition, as another embodiment, iron pieces are embedded in portions to which forces are applied or which are liable to be worn.
    Type: Grant
    Filed: April 13, 1992
    Date of Patent: April 26, 1994
    Assignees: Akebono Brake Industry Co., Ltd., Akebono Research and Development Centre, Ltd.
    Inventor: Shigeyoshi Kobayashi
  • Patent number: 5302008
    Abstract: A brake control system for a vehicle in which a brake pressure is generated in accordance with a signal from an electronic control unit for applying the brake pressure to vehicle wheels, characterized in that a mechanical brake system is automatically actuated when an unexpected electrical fault has occurred in an electrical brake system.
    Type: Grant
    Filed: September 4, 1992
    Date of Patent: April 12, 1994
    Assignees: Akebono Brake Industry Co., Ltd., Akebono Research and Development Centre Ltd.
    Inventors: Katsuya Miyake, Tatsuo Ogawahara, Takashi Kunimi, Tadashi Kobayashi, Masahiro Nezu, Kimio Takahashi, Masatomo Mori, Takashi Kurosawa
  • Patent number: 5282675
    Abstract: An anti-lock control arrangement for a vehicle which employs a control map for effectively preventing a wheel lock during braking. The control map is defined in terms of acceleration-deceleration values of a vehicle speed, which is to be controlled, and a speed difference between a target speed and a vehicle speed. The control map is read during anti-lock operation to effectuate control of the brake hydraulic pressure.
    Type: Grant
    Filed: November 13, 1992
    Date of Patent: February 1, 1994
    Assignees: Akebono Research and Development Centre, Ltd., Akebono Brake Industry Co., Ltd.
    Inventors: Satomi Okubo, Toshifumi Maehara
  • Patent number: 5279777
    Abstract: A process for producing a friction material under low-temperature conditions using, as a reinforcement, one or more fibers selected from a metal fiber, an organic fiber and an inorganic fiber and, as a binder, a compounded pitch that consists of a mesophase pitch and sulfur and/or an aromatic nitro compound. The content of an optically anisotropic phase in the mesophase pitch is at least 80% and the softening point of the mesophase pitch is not higher than 270.degree. C. The friction material produced exhibits consistent friction characteristics over a broad temperature range.
    Type: Grant
    Filed: October 28, 1992
    Date of Patent: January 18, 1994
    Assignees: Mitsubishi Gas Chemical Co., Inc., Akebono Research and Development Centre, Ltd.
    Inventors: Takashi Kojima, Hitoshi Sakamoto, Nobuo Kamioka, Hiroshi Tokumura
  • Patent number: 5238089
    Abstract: A device for preventing the squeak in a disc brake apparatus in which friction pads comprised of a semi-metallic or a non-asbestos material are pushed onto a disc rotor to perform braking is characterized in that the disc rotor is circumferentially divided by the use of slits or couplings so that the frequency of second-order resonance in the longitudinal vibration of the rotor is higher than 15 kHz and thus inaudible to humans.
    Type: Grant
    Filed: August 3, 1992
    Date of Patent: August 24, 1993
    Assignees: Akebono Brake Industry Co., Ltd., Akebono Research and Development Centre, Ltd.
    Inventors: Mikio Matsuzaki, Toru Yoshino, Toshitaka Izumihara
  • Patent number: 5231861
    Abstract: Method of processing brake pads having a lining member mounted on a back plate is disclosed. An exposed surface of the lining member initially having a substantially planar configuration is heated to a warping temperature between substantially 300.degree. C. and substantially 800.degree. C. to be permanently warped the brake pad into a substantially concave configuration. Then the exposed surface of the lining member is ground into a substantially planar configuration, while maintaining the warped condition of the brake pad.
    Type: Grant
    Filed: November 21, 1991
    Date of Patent: August 3, 1993
    Assignees: Akebono Brake Industry Co., Ltd., Akebono Research and Development Centre Ltd.
    Inventors: Hiroshi Tokumura, Yukikazu Koyanagi, Toru Yoshino
  • Patent number: 5217528
    Abstract: A non-asbestos friction material comprising mica powder adhered with aluminum phosphate and then subjected to the heating treatment, friction modifier and thermosetting resin binder is disclosed. The material is used for the brake lining and clutch facing for cars and industrial machinery.
    Type: Grant
    Filed: October 18, 1991
    Date of Patent: June 8, 1993
    Assignees: Akebono Brake Industry Co., Ltd., Akebono Research and Development Centre Ltd.
    Inventor: Katsuji Seki
  • Patent number: 5185703
    Abstract: An anti-lock control method and apparatus is charecterized in that if the highest one VwH of the speeds of the four wheels of the vehicle is still lower than a prescribed threshold speed and not increasing at a second time point at which a prescribed time .DELTA.T has elapsed after a first time point at which the highest wheel speed becomes lower than the threshold speed, the estimated vehicle speed is modified to be equal to the highest wheel speed VwH, thereby preventing an automotive vehicle from being not braked at the start of anti-lock control immediately after an estimated vehicle speed has changed away from the actual vehicle speed as the wheel of the vehicle performs an acceleration slip before the start of the anti-lock control.
    Type: Grant
    Filed: December 26, 1990
    Date of Patent: February 9, 1993
    Assignees: Akebono Brake Industry Co., Ltd., Akebono Research and Development Centre Ltd.
    Inventor: Satomi Okubo
  • Patent number: 5185702
    Abstract: An anti-lock control apparatus and method in which the brake hydraulic pressure is controlled by regarding an estimated vehicle speed as an actual vehicle speed, is characterized in that the estimated vehicle speed is corrected when the estimated vehicle speed is extremely reduced relative to the actual vehicle speed when the four wheel speeds are reduced at the same time, or the like, thereby preventing the estimated vehicle speed from being away from the actual speed. It can be applied as the correction of the estimated vehicle speed that the estimated vehicle speed may be maintained at a constant value, and the deceleration and acceleration of the estimated vehicle speed may be varied in accordance with a friction coefficient of the road surface.
    Type: Grant
    Filed: January 21, 1992
    Date of Patent: February 9, 1993
    Assignees: Akebono Research and Development Centre Ltd., Akebono Brake Co., Ltd.
    Inventor: Satomi Okubo
  • Patent number: 5185704
    Abstract: In the vehicle using the three-channel anti-lock control method based on the front wheel independent-and-rear wheel select-low, only when the third system speed Vs3 to which the left and right rear wheels belong is subjected to the anti-lock control due to the abruptly decreasing of the third system speed before at least one of the left and right front wheel systems begin to be subjected to the anti-lock control, the decrease of the brake hydraulic pressure is not started even if the third system speed Vs3 becomes lower than the above threshold speed VT1 (Vs3<VT1). In such case, only when the third system speed Vs3 becomes equal to or lower than the reference speed Vr (Vs3.ltoreq.Vr), the decrease of the hydraulic pressure is started. By doing so, an excessive decrease of the brake hydraulic pressure in the third system at the time of the braking during the turning of the vehicle is prevented.
    Type: Grant
    Filed: August 29, 1990
    Date of Patent: February 9, 1993
    Assignees: Akebono Research and Development Centre Ltd., Akebono Brake Co., Ltd.
    Inventor: Satomi Okubo
  • Patent number: 5183632
    Abstract: A method of manufacturing an aluminum-base composite disc rotor comprising the steps of preparing a rough-shaped disc rotor made of a mixture of aluminum powder or aluminum alloy powder with reinforcing particles or aluminum alloy, placing a mixture of aluminum powder or aluminum alloy powder with reinforcing particles or a preform made thereof on each of fixed positions of the rough-shaped disc rotor, and heating the mixture or the preform to at least a region of mashy state temperature to mold under pressure. Thereby the heat resistance and the wear resistance of the aluminum-base composite disc rotor for light-duty cars and industrial machinery are improved.
    Type: Grant
    Filed: March 3, 1992
    Date of Patent: February 2, 1993
    Assignees: Akebono Brake Industry Co., Ltd., Akebono Research and Development Centre Ltd.
    Inventors: Manabu Kiuchi, Masao Arai
  • Patent number: 5171072
    Abstract: A brake hydraulic pressure generator is provided which employs a first booster piston which applies a brake pedal treading force to a brake piston and a second booster piston which selectively additively increases the braking pedal treading force applied to the brake piston. The second booster piston is operated by hydraulic fluid pressure supplied from an auxiliary hydraulic pressure source.
    Type: Grant
    Filed: May 17, 1990
    Date of Patent: December 15, 1992
    Assignees: Akebono Brake Industry Co., Ltd., Akebono Research and Development Centre, Ltd.
    Inventor: Toshifumi Maehara
  • Patent number: 5157612
    Abstract: A method for controlling an anti-lock system of vehicles comprising steps of determining an estimated vehicle speed in accordance with the highest speed of four vehicle wheels speeds, calculating an average deceleration value at intervals of a constant time of the estimated vehicle speed, judging a frictional coefficient of the road surface on which the vehicle runs, and applying the frictional coefficient commonly to a plurality of control systems.
    Type: Grant
    Filed: August 2, 1990
    Date of Patent: October 20, 1992
    Assignees: Akebono Brake Industry Co., Ltd., Akebono Research and Development Centre Ltd.
    Inventor: Okubo Satomi
  • Patent number: 5147588
    Abstract: A hybrid carbon/carbon composite and a method of manufacturing a hybrid carbon/carbon composite, wherein a raw material containing carbon fibers with two or more different lengths and meso-phase carbon as a binder are raw materials. The raw materials are kneaded in the presence of adhesives, dried and defibrated, then molded under heat and pressure by hot press, and thereafter subjected to heat treatment.
    Type: Grant
    Filed: June 12, 1990
    Date of Patent: September 15, 1992
    Assignees: Akebono Brake Industry Co., Ltd., Akebono Research and Development Centre Ltd.
    Inventors: Akimitsu Okura, Toushoku Chou, Nobuo Kamioka
  • Patent number: 5134005
    Abstract: A ring-shaped friction element for operating in oil provided with a plurality of oil containers at an inner peripheral portion thereof and a plurality of grooves communicating between the oil containers and an outer periphery of the friction element.
    Type: Grant
    Filed: July 3, 1990
    Date of Patent: July 28, 1992
    Assignees: Akebono Brake Industry Co., Ltd., Akebono Research and Development Centre Ltd.
    Inventors: Susumu Wada, Yoshihiro Fujita
  • Patent number: 5126997
    Abstract: A system for controlling brake pressure on a drive wheel of a motor vehicle, comprising a device for detecting the speed and acceleration of the drive wheel; a brake mechanism including a fluid therein for exerting brake pressure on the drive wheel; a pedal mechanism for manual operation of the brake means; and a control device for deactivating the pedal mechanism when the acceleration exceeds a predetermined initial acceleration value or the speed of the drive wheel exceeds a predetermined first threshold value.
    Type: Grant
    Filed: August 2, 1990
    Date of Patent: June 30, 1992
    Assignees: Akebono Brake Industry Co., Ltd., Akebono Research and Development Centre Ltd.
    Inventors: Hirohide Fukuda, Katsuya Miyake, Yoshio Takahashi, Yuzo Nakakuki, Kinji Ogino, Tadashi Iwamoto
  • Patent number: 5123715
    Abstract: A road surface friction coefficient estimating method and apparatus in an anti-lock control device for preventing locking of vehicle wheels during braking. The road surface friction coefficient is estimated by comparing a deceleration of an estimated vehicle speed with a predetermined threshold value. The predetermined threshold value has different road surface friction coefficient values corresponding to different vehicle deceleration values. The braking hydraulic pressure is then repeatedly varied in accordance with signals indicative of the estimated road surface friction coefficient, signals indicative of the estimated vehicle speed, and one of the signals indicative of the slowest rear wheel speed and the front wheel speeds.
    Type: Grant
    Filed: February 13, 1991
    Date of Patent: June 23, 1992
    Assignees: Akebono Brake Industry Co., Ltd., Akebono Research and Development Centre Ltd.
    Inventor: Satomi Okubo
  • Patent number: 5098170
    Abstract: A vacuum booster for use with a vehicle anti-locking brake system to constitute a traction control system for preventing the slip operation of the vehicle driving wheel during starting or accelerating the vehicle, comprising a main opposing pressure chamber, an auxiliary opposing pressure chamber, a continuous pressure chamber, an operation rod and a pair of valves for independently controlling each of the main and auxiliary opposing pressure chambers so that control of the slip operation of the vehicle driving wheel can be performed without depressing the vehicle brake pedal.
    Type: Grant
    Filed: February 8, 1990
    Date of Patent: March 24, 1992
    Assignees: Akebono Brake Industry Co., Inc., Akebono Research and Development Centre Ltd.
    Inventor: Namio Watanabe
  • Patent number: 5098172
    Abstract: A hydraulic brake pressure generation apparatus which is provided with a pressure increasing valve apparatus, a fluid pressure increasing apparatus and a power valve. The pressure increasing valve apparatus receives a fluid pressure in a fluid pressure chamber of a master cylinder and then generates a fluid pressure the force of which is larger by a predetermined amount than the fluid pressure in the fluid pressure chamber.
    Type: Grant
    Filed: September 10, 1990
    Date of Patent: March 24, 1992
    Assignees: Akebono Brake Industry Co., Ltd., Akebono Research and Development Centre Ltd.
    Inventor: Toshifumi Maehara