Patents Assigned to Akebono
  • Patent number: 4889395
    Abstract: Disclosed is an anti-lock control apparatus for an air over hydraulic brake system having a first air pressure line leading from a brake valve to an air master cylinder as well as a second air pressure line branching from the first air pressure line and leading to a modulator. The second air pressure line is provided with an exhaust-side check value for exhausting air from a pneumatic chamber of the modulator and an air-supply side check valve for supplying air to the pneumatic chamber. The pneumatic chamber of the modulator and the second air pressure line are adapted to hold residual pressure, thereby increasing the rising gate of the braking hydraulic pressure during braking and the falling rate of the braking hydraulic pressure during release of braking, and reducing the amount of air consumed.
    Type: Grant
    Filed: March 2, 1989
    Date of Patent: December 26, 1989
    Assignee: Akebono Brake Industry Co., Ltd.
    Inventors: Tomohiro Fujita, Ryuji Kawano
  • Patent number: 4887449
    Abstract: A method for forming a cup-shaped piston having a peg comprises a first preform step forming a first preform having a flat top surface and a recessed portion at its bottom, a second preform step forming therein a second preform having a projecting or recessed portion on the top surface of the end portion in order to readily form a peg, and a final step finishing the second preform to have the cup-shaped piston having the peg.
    Type: Grant
    Filed: August 31, 1988
    Date of Patent: December 19, 1989
    Assignee: Akebono Brake Industry Co., Ltd.
    Inventors: Tamotsu Kanai, Katsunori Hayashi
  • Patent number: 4884492
    Abstract: A hydraulic booster includes a power piston which is inserted slidably into a cylinder member and has a tip portion which is coupled to a piston of a master cylinder, a pressure chamber disposed in the rear of the power piston, a return valve provided in such a manner as to open and close a channel for connecting the pressure chamber to a reservoir, and a supply valve disposed in such a manner as to connect the pressure chamber to a high-pressure fluid source, a high-pressure fluid being introduced into the pressure chamber as the return valve is closed and the supply valve is opened. A valve sleeve is slidably inserted in the power piston and is urged rearwardly of the power piston by a spring, and a cam portion provided in the valve sleeve is employed to open and close the supply valve.
    Type: Grant
    Filed: June 29, 1988
    Date of Patent: December 5, 1989
    Assignees: Akebono Brake Industry Co., Ltd., Akebono Research and Development Centre Ltd
    Inventor: Toshifumi Maehara
  • Patent number: 4883325
    Abstract: In an anti-lock control system for motor vehicles, the design is made such that when the motor vehicle is running on a rough road, reduction of the brake hydraulic pressure can be prevented from being started early by detecting that the motor vehicle is running on the rough road, and such that any adverse effects can be avoided which tend to be produced in the case where a device for coping with the rough road is applied when the road surface on which the motor vehicle is running is a low-.mu. road surface or when the motor vehicle is running with a low speed.
    Type: Grant
    Filed: February 9, 1989
    Date of Patent: November 28, 1989
    Assignee: Akebono Brake Industry Co., Ltd.
    Inventors: Haruki Shimanuki, Takao Maki, Yoshio Takahashi
  • Patent number: 4872584
    Abstract: The present invention concerns a safety device for a radiator cap detachably mounted on a fluid supply opening for closing the radiator opening. The safety device comprises a lock means for preventing the opening of the radiator cap when the temperature of the coolant in the radiator is higher than a predetermined value. The lock means is provided between the radiator cap and an inner surface of the fluid supply opening. The lock means comprises a lock portion provided on an inner surface of the fluid supply opening and a lock member fixedly secured to the radiator cap. The lock member is formed of a shape memory alloy.
    Type: Grant
    Filed: July 27, 1988
    Date of Patent: October 10, 1989
    Assignees: Akebono Brake Industry Co., Ltd., Akebono Research and Development Centre Ltd.
    Inventor: Takashi Sakai
  • Patent number: 4867509
    Abstract: Apparatus for controlling brake fluid pressure of a vehicle includes a hold valve provided in a first fluid passage so as to control fluid communication between a fluid pressure chamber in a master cylinder and a wheel cylinder, a decay valve provided in a second fluid passage so as to control fluid communication between a wheel cylinder and a reservoir; a supply valve provided in a third fluid passage so as to control the flow of brake fluid from a fluid pressure source to the fluid pressure chamber; an intake valve normally held in its closed position to shut off the third fluid passage, and a valve operating member mounted on the piston for movement therewith, the valve operating member being engageable with the intake valve when the stroke of movement of the piston reaches a predetermined value to thereby move the intake valve to its open position. With this construction, an anti-lock control for preventing the locking of the vehicle wheels can be effected.
    Type: Grant
    Filed: October 24, 1988
    Date of Patent: September 19, 1989
    Assignees: Akebono Brake Industry Co., Ltd., Akebono Research and Development Centre Ltd.
    Inventors: Toshifumi Maehara, Takashi Sakai
  • Patent number: 4859414
    Abstract: An alloy for disk rotor utilized in disk brake is disclosed, which contains 2.3 to 3.0 wt. % of silicon, 1.0 to 3.0 wt. % of manganese, 0.2 to 1.0 wt. % chromium, 0 to 2.0 wt. % of copper and 3.7 to 4.2 wt. % of carbon, the remainders being inevitable impurities and iron.
    Type: Grant
    Filed: April 19, 1988
    Date of Patent: August 22, 1989
    Assignees: Akebono Brake Industry Co., Ltd., Akebono Research and Development Centre Ltd.
    Inventor: Masao Arai
  • Patent number: 4852702
    Abstract: An automatic adjuster for the operation gap of a brake, comprising a piston slidably fitted in a cylinder, an adjusting nut supported in contact with the outer end of the piston the adjusting nut being rotatable relative to the piston, an unrotatable adjusting screw supporting a brake friction member at the outer end of the screw and engaged with the internal thread of the nut at the external thread to form a non-reversible screw-thread connection, the adjusting screw and the adjusting nut cannot rotate relative to each other by any force acting to the non-reversible screw-thread connection in the axial direction thereof, a drive screw connected to the cylinder through a friction clutch and engaged with the external thread of the nut at the internal thread to form a reversible screw-thread connection which has a backlash corresponding to the operation gap, the drive screw and the adjusting nut can rotate relative to each other by a force acting to the reversible screw-thread connection in the axial direction
    Type: Grant
    Filed: May 12, 1988
    Date of Patent: August 1, 1989
    Assignee: Akebono Brake Industry Co., Ltd.
    Inventor: Kiyokazu Kaneko
  • Patent number: 4846314
    Abstract: An automatic gap adjustment device for a disc brake comprising a cup-shaped piston which has a bottom in the fore end thereof and is arranged to move within a cylinder of a caliper, a sleeve which is axially disposed within the piston and is arranged to be carried by the piston when the piston is moved forward by the action of hydraulic pressure, and a spindle which is in screwed engagement with the piston and is arranged to rotate and screw out from the sleeve rearward relative to the piston. The automatic gap adjustment device is arranged to have the hydraulic pressure received as a moving force directed toward the rear part of the spindle, to have an adjuster piston arranged within a cylinder to push and cause a protruding end part of the spindle which protrudes toward the rear of the sleeve to engage an engaging part provided within the cylinder.
    Type: Grant
    Filed: July 18, 1988
    Date of Patent: July 11, 1989
    Assignee: Akebono Brake Industry Co., Ltd.
    Inventor: Yutaka Nishikawa
  • Patent number: 4846316
    Abstract: A hydraulic retarder and brake unit mounted on a rotating vehicle drive shaft has a first rotatable member forming a brake drum and mounted on the drive shaft for rotation therewith. A non-rotatable member supports brake shoes movable into frictional engagement with a lining of the brake drum and are actuated by the lever for frictionally braking rotation of the drive shaft. A plurality of stator vanes are formed on the non-rotatable member. A second rotatable member is mounted on the drive shaft for free rotation independently of the rotation of the drive shaft, while a plurality of rotor vanes are freely rotatably mounted around the drive shaft and in facing opposition to the stator vanes for providing a hydraulic coupling. A clutch selectively rotatably couples the second rotatable member with the first rotatable member so that the rotor vanes are rotated with the drive shaft and the rotation of the drive shaft retarded.
    Type: Grant
    Filed: April 13, 1988
    Date of Patent: July 11, 1989
    Assignee: Akebono Brake Industry Co., Ltd.
    Inventor: Hideyuki Fujinami
  • Patent number: 4844555
    Abstract: An anti-lock control device in a 2-channel diagonal brake composed of two individual brake lines, one controlling the front left and the rear right wheel, and the other the front right and the rear left wheel. When pressure reduction occurs in one brake line during anti-lock control, a cut valve closes the brake fluid passage to the rear wheel in the other brake line so as to retain the fluid pressure of the rear wheel at a constant value. Further, when one brake line fails to function, the cut valve for opening and closing the brake fluid passage to the rear wheel in the other brake line is put in a normally open condition.
    Type: Grant
    Filed: December 14, 1988
    Date of Patent: July 4, 1989
    Assignees: Akebono Brake Industry Co., Ltd., Akebono Research and Development Centre Ltd.
    Inventor: Toshifumi Maehara
  • Patent number: 4828079
    Abstract: For the improvement in the hydraulic retarder comprising a fixed member (1) of vehicle, a shaft (2), a housing (4), a vane chamber (3), a plurality of stator vanes (5) and a plurality of rotor vanes (7), a drum-like member (10), a plurality of clutch pistons (14a), (14b), (14c), a cylindrical member (6) a pair of arcuate brake shoes (16) and a parking lever (21) are added to function respectively.
    Type: Grant
    Filed: May 16, 1988
    Date of Patent: May 9, 1989
    Assignee: Akebono Brake Industry Co., Ltd.
    Inventor: Hideyuki Fujinami
  • Patent number: 4815573
    Abstract: A liquid-cooled disc brake for use in a vehicle having a rotatable shaft, at least one rotor fitted to the outer peripheral surface of the shaft, in which the rotor is unrotatable but slightly axially movable with respect to the shaft, a caliper secured to the vehicle body, having a first wall, a second wall positioned opposite to the first wall and a third wall. The caliper is substantially U-shaped in section with its inner peripheral side opening to thereby surround the whole perimeter of the rotor. The second wall of the caliper is made hollow so that the cooling liquid circulates freely through the hollow portion of the second wall. The disc brake further includes means for thrusting against the rotor provided at an inner side of the first wall of the caliper. The thrust means is operated at the time when the brake is performed.
    Type: Grant
    Filed: October 1, 1987
    Date of Patent: March 28, 1989
    Assignees: Akebono Brake Industry Co., Ltd, Akebono Research & Development Centre Ltd.
    Inventor: Katsuhiro Miyata
  • Patent number: 4811232
    Abstract: An apparatus for measuring the wheel speed for an anti-skid control system of a motor vehicle, comprising a sensor for generating a pulse signal, the cycle of which corresponds to the rotational speed of the wheel. The wheel speed signal is provided in every control cycle having a constant time. If the wheel speed is not provided because the rotational speed of the wheel is low, the anti-skid control is performed in accordance with a compensated wheel speed calculated on the basis of the wheel speed measured immediately beforehand.
    Type: Grant
    Filed: April 10, 1987
    Date of Patent: March 7, 1989
    Assignees: Fujitsu Limited, Akebono Brake Industry Co., Ltd.
    Inventors: Akira Hoashi, Hideo Akima, Takao Maki, Isao Yamaki
  • Patent number: 4807943
    Abstract: The brake control system for use in a vehicle includes a compression cylinder device, which communicates with a fluid passage between a gate valve and a wheel cylinder. A compression piston is reciprocately disposed inside of the compression cylinder device. A cut off valve member is disposed in the compression cylinder device, which closes a fluid supply passage between a fluid chamber of the compression cylinder device and the wheel cylinder of the brake device for the driven wheel. The system further includes a valve system provided between an accumulator and the compression cylinder device. The valve system is provided for selectively supplying the brake fluid pressure in the accumulator to the compression cylinder device during the lock-preventing and acceleration slip-preventing controls.
    Type: Grant
    Filed: December 8, 1987
    Date of Patent: February 28, 1989
    Assignees: Akebono Brake Industry Co., Ltd., Akebono Research & Development Centre Ltd.
    Inventor: Kinji Ogino
  • Patent number: 4807133
    Abstract: In an anti-skid control system for motor vehicle, there is provided means adapted, when the motor vehicle is running on a rough road, to detect that the road on which the motor vehicle is now running is a rough one, thereby preventing reduction of brake hydraulic pressure from being started early.
    Type: Grant
    Filed: May 8, 1987
    Date of Patent: February 21, 1989
    Assignees: Akebono Brake Industry Co., Ltd., Fujitsu Limited
    Inventors: Haruki Shimanuki, Hideo Akima, Akira Hoashi
  • Patent number: 4802713
    Abstract: A system for controlling a motor vehicle brake comprising a supply-and-exhaust valve group which supplies hydraulic pressure for a brake to wheel cylinders of brakes and exhausts hydraulic pressure in the wheel cylinders. A switch valve group which controls a supply to the decompression valve so that hydraulic pressure is supplied to the supply-and-exhaust valve group whether passing through the decompression valve or not. Slip dectecting device detects a slipping status of the driving wheels. Slipping threshold value setting device which determines a slipping threshold. Deceleration status detecting device detects a deceleration status of wheels when the vehicle decelerates. Deceleration status threshold value setting device determines a deceleration status threshold value.
    Type: Grant
    Filed: September 9, 1987
    Date of Patent: February 7, 1989
    Assignees: Akebono Brake Industry Co., Ltd., Akebono Research and Development Centre Ltd.
    Inventor: Kinji Ogino
  • Patent number: 4797825
    Abstract: An anti-skid control system for motor vehicles is provided wherein when the time period from when the wheel velocity being decreased reaches a second reference velocity to a low peak of the wheel velocity at which the reduction of the brake pressure is to be stopped, is longer than a predetermined time period, the reduction of the brake pressure is continued until the wheel velocity is increased up to a first reference velocity which is higher than the second reference velocity. In this way, even if the wheel velocity drops sharply because the coefficient of friction of the road surface suddenly changes from high to low, the wheel velocity recovers so that the wheels of the motor vehicle are prevented from locking early.
    Type: Grant
    Filed: December 29, 1986
    Date of Patent: January 10, 1989
    Assignees: Akebono Brake Industry Co., Ltd., Fujitsu Limited
    Inventors: Haruki Shimanuki, Katsuya Miyake, Hideo Akima, Akira Hoashi
  • Patent number: 4792193
    Abstract: In anti-skid control system for motor vehicles of the type that the drive system of the motor vehicle is switchable to direct-coupled 4WD system, brake pressure reduction starting points in the anti-skid control are set up to come earlier when the drive system of the motor vehicle is switched to the direct-coupled 4WD system than when said drive system is other than the direct-coupled 4WD system.
    Type: Grant
    Filed: October 1, 1987
    Date of Patent: December 20, 1988
    Assignee: Akebono Brake Industry Co., Ltd.
    Inventors: Yoshio Takahashi, Hiroyuki Yoshizawa
  • Patent number: 4790221
    Abstract: A caliper machining apparatus for machining a caliper for a disc brake is disclosed which comprises: a cutter for cutting the caliper, a facing mechanism for positioning and facing the cutter relative to the caliper. The facing mechanism includes a hollow rotary spindle, a facing head fixed to the rotary spindle, a slider movable only in a diametric direction of the facing head, and slidingly moved in eccentric relation with a rotary center of the rotary spindle and a facing shaft passing through the rotary spindle. The facing shaft is allowed to rotate with the rotary spindle but to be displaceable in an axial direction relative to the rotary spindle. The rotary spindle is rotated by a main motor. The facing shaft is moved in the axial direction by the rotation of a facing motor.
    Type: Grant
    Filed: October 14, 1987
    Date of Patent: December 13, 1988
    Assignee: Akebono Brake Industry Co., Ltd.
    Inventors: Yukio Iwata, Shigenori Matsumoto