Patents by Inventor Hideo Akima

Hideo Akima 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: 5485901
    Abstract: An electromagnetic brake comprises a plurality of electromagnetic coils disposed on a stationary part of a drive force supply unit and producing a magnetic field in response to energizing currents supplied thereto, a rotor made of a conductive material and disposed on a rotary shaft of the drive force supply unit and positioned so as to rotate in the magnetic field and produce an eddy current in the rotor. The eddy current converts the rotational energy imparted to the rotor through the shaft into heat and generates a breaking force. A switching unit connected to the electromagnetic coils selectively controls the flow of energizing current to the coils in accordance with switching data supplied thereto by a control unit, responsive to external control data, for selectively controlling the ON/OFF ratio of energizing current flow to the electromagnetic coils.
    Type: Grant
    Filed: October 11, 1991
    Date of Patent: January 23, 1996
    Assignees: Fujitsu Ltd., Tokyo Buhin Kogiyo Co., Ltd.
    Inventors: Hideo Akima, Yoshikiyo Ishikura, Takaaki Kishi
  • Patent number: 5002148
    Abstract: A traction control method/apparatus for motor vehicles is arranged such that at an initial stage of the starting or accelerating operation of the motor vehicle where a large amount of slip of the driving wheel tends to be caused, a braking force is sufficiently applied to the driving wheel to restrain the slip thereof; and after the engine output is adjusted through accelerator or throttle control which is performed simultaneously with the application of the braking force, the procedure for controlling the brake hydraulic pressure is changed to eliminate the difference between the lefthand and righthand driving wheel speeds.
    Type: Grant
    Filed: January 23, 1989
    Date of Patent: March 26, 1991
    Assignees: Akebono Brake Industry Co., Ltd., Akebono Research and Development Centre Ltd., Fujitsu Limited
    Inventors: Katsuya Miyake, Kinji Ogino, Shigeki Moride, Hideo Akima
  • Patent number: 4930083
    Abstract: An anti-skid brake control system for a motor vehicle comprising: a wheel speed sensor which is disposed for each wheel of a vehicle and generates a pulse signal having a pulse cycle which corresponds to a revolution speed of each wheel; a pulse cycle measuring circuit for detecting the cycle of the pulses of the pulse signal from the wheel speed sensor; and, condition setting means for setting anti-skid brake control condition factors in accordance with the wheel speed. The anti-skid brake system is controlled in accordance with the condition factors set by the condition setting means.
    Type: Grant
    Filed: October 20, 1988
    Date of Patent: May 29, 1990
    Assignee: Fujitsu Limited
    Inventors: Akira Hoashi, Hideo Akima, Haruki Shimanuki, Yuji Matsubara
  • Patent number: 4870582
    Abstract: An anti-skid brake control system for a motor vehicle comprises: a wheel speed sensor which is provided for each wheel of the vehicle and generates a pulse signal having a pulse cycle which corresponds to a revolutional speed of each wheel; a pulse cycle measuring circuit for detecting the cycle of the pulses of the pulse signal from each wheel speed sensor; and, a discriminator for discriminating an actual acceleration or deceleration state. The actual acceleration or deceleration state is discriminated in accordance with whether or not the period of the acceleration or deceleration state is longer than a predetermined time. The acceleration or deceleration state is calculated from the wheel speed data detected by the pulse cycle measuring circuit, and the system is controlled on the basis of the result of the discrimination by the discriminator.
    Type: Grant
    Filed: March 20, 1987
    Date of Patent: September 26, 1989
    Assignee: Fujitsu Limited
    Inventors: Akira Hoashi, Hideo Akima, Katsuya Miyake, Isao Yamaki
  • Patent number: 4825371
    Abstract: An anti-skid control system for a motor vehicle, includes a brake fluid pressure buildup-control mode and a brake fluid pressure reduction mode, each of which occur cyclically. In each buildup-control mode, a control valve is repetitively opened and closed so that brake fluid pressure buildup and holding operations are performed alternately. The time period of each buildup-control mode is from a high peak of a wheel speed signal until a point of intersection between a reference velocity V.sub.W0 and the wheel speed V.sub.W. The reference velocity V.sub.W0 has an initial point Q positioned under the high peak V.sub.HP of the wheel speed V.sub.W by a velocity value .DELTA.V and extending straight at a gradient .theta.. The speed value .DELTA.V, the gradient .theta., and an initial pressure buildup time T.sub.P, in each building-control mode, are determined in accordance with the wheel acceleration in the preceding wheel acceleration, i.e., coefficient of friction of the road surface.
    Type: Grant
    Filed: March 20, 1987
    Date of Patent: April 25, 1989
    Assignee: Fujitsu Limited
    Inventors: Akira Hoashi, Hideo Akima, Katsuya Miyake, Isao Yamaki
  • 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: 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: 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: 4790420
    Abstract: The present invention relates to a vehicle such as a forklift in which a hydraulic pump for driving the fork is driven by the same engine used to provide motive power to the vehicle. A inching control is provided in cases where an automatic transmission is employed for shifting the gears of the vehicle. The inching control controls the clutch to allow separate control of the motive system and cargo handling system of the vehicle. This control must be operated by an operator through the inching pedal. In the fork lift, the clutch plate wears excessively and therefore the relation between the amount of depressing of the inching pedal and engagement of clutch changes abruptly. The present invention discloses a technique to adequately measure the clutch position and for compensating for control of the clutch by always keeping constant the relation between the amount of depression of the inching pedal and the amount of engagement of the clutch.
    Type: Grant
    Filed: July 3, 1986
    Date of Patent: December 13, 1988
    Assignees: Fujitsu Limited, Kabushiki Kaisha Toyoda Jidoshokki Seisakusho
    Inventors: Seiichi Hata, Hideo Akima, Kiyoshi Kitagawa, Masaya Hyodo, Koji Niinomi
  • Patent number: 4773714
    Abstract: An anti-skid control system for motor vehicles is provided wherein a computed wheel speed Vv is set up on the basis of the highest one of the wheel speeds of the motor vehicle; a first reference speed VT1 and a second reference speed VT2 are set up which are lower than and follow the computed vehicle speed Vv either with a first and second predetermined speed difference respectively or with a first and a second predetermined ratio respectively, the first reference speed VT1 being higher than the second reference speed VT2 (VT1>VT2); in the case where the wheel speed continues decreasing with a deceleration lower than a predetermined threshold level of deceleration, reduction of brake pressure is started at a point of time when a predetermined time period T1 elapsed from a point of time when the wheel speed reached the level of the second reference speed VT2; and the reduction of the brake pressure is stopped at a point of time when the wheel speed was increased up to the level of the first reference speed
    Type: Grant
    Filed: December 29, 1986
    Date of Patent: September 27, 1988
    Assignees: Akebono Brake Industry Co., Ltd., Fujitsu Limited
    Inventors: Haruki Shimanuki, Katsuya Miyake, Hideo Akima, Akira Hoashi
  • Patent number: 4774668
    Abstract: An anti-skid control system for motor vehicles is provided wherein a computed vehicle speed is set up on the basis of respective wheel speeds of the motor vehicle; a reference speed which is lower than the computed vehicle speed by a predetermined amout and follows the computed vehicle speed with such a speed difference, is calculated on the basis of the computed vehicle speed; a high peak of the wheel speed is compared with the reference speed; when the high peak of the wheel speed is equal to or higher than the reference speed, the brake pressure is increased; and when the high peak of the wheel speed is lower than the reference speed, the brake pressure is reduced again.
    Type: Grant
    Filed: December 29, 1986
    Date of Patent: September 27, 1988
    Assignees: Akebono Brake Industry Co., Ltd., Fujitsu Limited
    Inventors: Yuji Matsubara, Isao Yamaki, Hideo Akima, Akira Hoashi
  • Patent number: 4773014
    Abstract: An anti-skid control system for motor vehicles is disclosed wherein in case the wheel speed is equal to or lower than a minimum speed which is detectable by a microcomputer, the wheel speed is set at a predetermined threshold speed level between the minimum speed and zero, thereby preventing reduction of brake pressure from being started when the wheel is lower than the threshold speed.
    Type: Grant
    Filed: December 29, 1986
    Date of Patent: September 20, 1988
    Assignees: Akebono Brake Industry Co., Ltd., Fujitsu Limited
    Inventors: Naoyuki Hagiya, Isao Yamaki, Hideo Akima, Akira Hoashi
  • Patent number: 4768636
    Abstract: A forward/reverse drive controller for controlling a vehicle, in which the output of an engine is transmitted through a clutch to an automatic transmission, in which the running direction of the vehicle is changed rapidly and alternately in opposite directions.
    Type: Grant
    Filed: January 9, 1987
    Date of Patent: September 6, 1988
    Assignees: Kabushiki Kaisha Toyoda Jidoshokki Seisakusho, Fujitsu Limited
    Inventors: Kazunori Ito, Masaya Hyodo, Koji Niinomi, Shingo Yamada, Yoshiyasu Uchida, Kiyoshi Kitagawa, Seiichi Hata, Hideo Akima, Toshihide Narita
  • Patent number: 4762375
    Abstract: An anti-skid control system for a motor vehicle in which, when a wheel speed to be controlled and being decreased through buildup of brake pressure becomes equal to a reference speed, this equality is judged as a fulfillment of a brake pressure reduction starting condition, and thus reduction of the brake pressure is started. The highest wheel speed is detected and a computed vehicle speed is set up based on the highest wheel speed by having the increase and decrease of the highest wheel speed limited to a predetermined range. The computed vehicle speed and the wheel speed to be controlled are compared; and when the comparison indicates that the wheel speed to be controlled is equal to or higher than the computed vehicle speed, no reduction of the brake pressure is started irrespective of whether the brake pressure reduction starting condition is fulfilled.
    Type: Grant
    Filed: December 29, 1986
    Date of Patent: August 9, 1988
    Assignees: Akebono Brake Industry Co., Ltd., Fujitsu Limited
    Inventors: Takao Maki, Isao Yamaki, Hideo Akima, Akira Hoashi
  • Patent number: 4741580
    Abstract: In an anti-skid control system for a motor vehicle, brake fluid pressure reduction-control mode and brake fluid pressure buildup-control mode occurs cyclically; in the reduction-control mode, reduction of the brake fluid pressure is started on the basis of detection of an abrupt drop in wheel speed which occurs when the wheel is braked; and in buildup-control mode, a valve is repetitively opened and closed so that brake fluid pressure buildup and holding operations are performed alternatley and repetitively, whereby the brake fluid pressure is caused to build up gradually.
    Type: Grant
    Filed: July 30, 1986
    Date of Patent: May 3, 1988
    Assignees: Akebono Brake Industry Co., Ltd., Fujitsu Limited
    Inventors: Yuji Matsubara, Hiroshi Ikegami, Hideo Akima, Akira Hoashi, Katsuya Miyake, Isao Yamaki, Toshifumi Maehara
  • Patent number: 4717209
    Abstract: An anti-skid control system for motor vehicles is provided wherein the higher one of the lefthand and righthand rear wheels is selected as a first computed speed; the lower one of the above two wheel speeds is selected as a second computed speed; the lower one of the first computed speed and lefthand front wheel speed is selected as a third computed speed; the lower one of the first computed speed and righthand front wheel speed is selected as a fourth computed speed; and a reference speed is set up on the basis of the first computed speed in such a manner that it is lower than the first computed speed by a predetermined amount and follows the first computed speed with such a speed difference.
    Type: Grant
    Filed: December 29, 1986
    Date of Patent: January 5, 1988
    Assignees: Akebono Brake Industry Co., Ltd., Fujitsu Limited
    Inventors: Naoyuki Hagiya, Yuji Matsubara, Katsuya Miyake, Hideo Akima, Akira Hoashi