Patents by Inventor Asaji Imanaka

Asaji Imanaka 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: 5713639
    Abstract: Brake control device for railroad stock has a braking force setting unit to add a braking force command signal for a powered car and braking force command signals for trailer cars and output a composite command signal. A main control device receives such composite signal and generates an electrical braking force. A braking force computation unit splits an error in a electrical braking force equivalent command signal corresponding to an actual electrical braking force with respect to such composite command signal into a supplementary hydraulic braking force command signal for a powered car and supplementary hydraulic braking force command signals for trailer cars and outputs results to hydraulic brake devices of such cars, wherein the command signals of such trailer cars are individual car command signals obtained by splitting such command signals in rolling stock units a plurality of times.
    Type: Grant
    Filed: February 26, 1996
    Date of Patent: February 3, 1998
    Assignee: Westinghouse Air Brake Company
    Inventors: Shigeaki Doto, Asaji Imanaka
  • Patent number: 5253930
    Abstract: An electromagnetic valve control system employing a controller circuit for controlling the position of a pneumatic valve by regulating the magnetizing current provided to the electrical solenoid by establishing a first magnetizing current set point when the valve is to be moved from a release position to a lap position and by establishing a second magnetizing current set point when the valve is to be moved from an application position to a lap position.
    Type: Grant
    Filed: September 25, 1991
    Date of Patent: October 19, 1993
    Assignee: Nippon Air Brake Co., Ltd.
    Inventors: Seiki Maruta, Asaji Imanaka
  • Patent number: 4886320
    Abstract: A vital pressure regulating system is constructed using an alternating current system, and the absolute value of an output signal is inversely proportional to the air pressure in the main air reservoir and therefore if some critical circuit component fails, the output of a comparator circuit becomes a direct current signal in the same way as the case in which the air pressure in the main air reservoir is higher than the predetermined upper limit value so that the switch shuts off the air compressor to achieve fail-safe operation.
    Type: Grant
    Filed: August 15, 1988
    Date of Patent: December 12, 1989
    Assignee: Nippon Air Brake Co., Ltd.
    Inventors: Asaji Imanaka, Kazutaka Nagata
  • Patent number: 4885693
    Abstract: A wheel slip detection system which is especially effective in cases where a gentle or sluggish slip simultaneously occurs on all the axles of a vehicle. For instance, when the velocity difference (.DELTA.V) between the standard speed, namely, the maximum axle speed, of two or more axles exceeds the preset velocity, this condition is detected as a slip state. In the present system, the first and second velocity values V.alpha.1 and V.alpha.2 are set, and it is detected as a slip of all axles when the following (a), (b), (c) states occur at each axle wherein:(a) V.alpha.1<.DELTA.V,(b) Max. .DELTA.V<V.alpha.2,(c) Max. axle acceleration<Standard acceleration.
    Type: Grant
    Filed: September 19, 1988
    Date of Patent: December 5, 1989
    Assignee: Nippon Air Brake Co., Ltd.
    Inventors: Asaji Imanaka, Tatsuo Fujiwara, Shuichi Osaka
  • Patent number: 4773447
    Abstract: The present invention discloses an electromagnetic valve for use in a railroad car slip prevention control of the brake system. Such electromagnetic valve having three-position control capability. The control position is selected based on an excitation current supplied to a solenoid valve.
    Type: Grant
    Filed: June 25, 1987
    Date of Patent: September 27, 1988
    Assignee: Nippon Air Brake Co., Ltd.
    Inventors: Asaji Imanaka, Mitsuhiro Ikeda
  • Patent number: 4763261
    Abstract: A wheel-speed detecting arrangement for detecting the wheel-speed of a vehicle having a fixed wheel-and-axle configuration includes a wheel generator connected to the wheel/axle configuration such that a first distance signal is produced indicating rotational displacement of the wheel. This first distance signal is then synchronized by use of a basic clock and passed onto a first counter which produces a first data signal indicative of the number of distance pulses. A second counter, enabled as a function of the output of the first counter, measures the number of clock pulses occurring within a measuring time period and generates a second data signal representing that time count. The first distance signal also operates a latch circuit such that, upon initial occurrence of any distance pulse, a reading of the second counter is taken and passed through to a calculating circuit.
    Type: Grant
    Filed: April 23, 1986
    Date of Patent: August 9, 1988
    Assignee: Nippon Air Brake Co., Ltd.
    Inventors: Asaji Imanaka, Tatsuo Fujiwara, Shuichi Osaka
  • Patent number: 4719536
    Abstract: A wheel-slip detection system and/or method for implementing self-readhesion or resticking viscous sticking phenomenon after all the wheels of a car have assumed a slipping condition. The detected data are self-retained until all of the wheel speed differences .DELTA.V become smaller than the first speed value .DELTA..alpha.2 regardless of the restoration of all wheel acceleration by the brake release application. Through this method, it is possible to prevent repeated occurrence of any simultaneous gentle or sluggish-slip state of all the wheels when self-readhesion application is not expected so that the increase of brake distance is avoided.
    Type: Grant
    Filed: April 9, 1986
    Date of Patent: January 12, 1988
    Assignee: Nippon Air Brake Co., Ltd.
    Inventors: Asaji Imanaka, Tatsuo Fujiwara, Shuichi Osaka
  • Patent number: 4685750
    Abstract: A railway vehicle brake control system in which a fluid pressure brake continuously supplements the electric brake as the electric brake effectiveness fades during vehicle slowdown. An amplifier circuit output signal corresponding to the electric brake effectiveness is modified by adjusting the amplifier gain in response to a detector sensing the initial drop in the electric brake effectiveness. This modified amplifier output signal is subtracted from a brake command signal to obtain a difference signal, the value of which establishes the amount of fluid pressure braking necessary to supplement the electric brake deficiency. The arrangement compensates for hysteresis and response delay in the pneumatic valving required in the fluid pressure brake system, such that the total brake obtained corresponds substantially to the brake command both during and following transition from the electric brake to the fluid pressure brake.
    Type: Grant
    Filed: September 2, 1986
    Date of Patent: August 11, 1987
    Assignee: Nippon Air Brake Co., Ltd.
    Inventor: Asaji Imanaka
  • Patent number: 4651071
    Abstract: A brake control system for a railway car having a primary electric brake and a secondary friction brake that supplements the electric brake as the electric brake effectiveness fades. The secondary friction brake is normally applied in accordance with a first supplementary control signal provided by an electrical component, such as an operational amplifier, the output of which is the difference between a brake command signal and the actual braking produced by the electric brake. A second supplementary control signal corresponding to the brake command signal is effective to control the secondary friction brake, in response to either anomalies in the power supply or failure of the operational amplifier. A switch connects the brake command signal to an electric-pneumatic converter to provide pneumatic pressure to the friction brake corresponding to the brake command, and to concurrently terminate operation of the electric brake, when either one or both of the foregoing abnormalities are detected.
    Type: Grant
    Filed: April 16, 1986
    Date of Patent: March 17, 1987
    Assignee: Nippon Air Brake Co., Ltd.
    Inventor: Asaji Imanaka
  • Patent number: 4639047
    Abstract: A railway vehicle brake control system in which a fluid pressure brake continuously supplements the electric brake as the electric brake effectiveness fades during vehicle slowdown. An amplifier circuit output signal corresponding to the electric brake effectiveness is modified by adjusting the amplifier gain in response to a detector sensing the initial drop in the electric brake effectiveness. This modified amplifer output signal is subtracted from a brake command signal to obtain a difference signal, the value of which establishes the amount of fluid pressure braking necessary to supplement the electric brake deficiency. The arrangement compensates for hysteresis and response delay in the pneumatic valving required in the fluid pressure brake system, such that the total brake obtained corresponds substantially to the brake command both during and following transition from the electric brake to the fluid pressure brake.
    Type: Grant
    Filed: April 8, 1985
    Date of Patent: January 27, 1987
    Assignee: Nippon Air Brake Co., Ltd.
    Inventor: Asaji Imanaka