Patents by Inventor Masahiro Tsukamoto

Masahiro Tsukamoto 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: 6283239
    Abstract: A disclosed auxiliary brake apparatus of a hybrid automobile includes a braking detector for detecting an operation of braking the hybrid automobile, an auxiliary brake electric motor capable of braking the hybrid automobile, and an auxiliary brake controller capable of controlling the auxiliary brake electric motor. The auxiliary brake controller controls the auxiliary brake electric motor to generate a counter torque in the auxiliary brake electric motor to thereby brake the hybrid automobile in accordance with the operation of braking the hybrid automobile detected by the braking detector when the controller determines that a failure occurs to the electric powered brake of the hybrid automobile.
    Type: Grant
    Filed: March 18, 1999
    Date of Patent: September 4, 2001
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Masahiro Tsukamoto, Tadayuki Hatsuda, Kouichiro Yonekura, Yoshio Shimoida
  • Patent number: 6231133
    Abstract: A brake pressure is controlled with the left and right front wheels of a vehicle as one group, and the left and right rear wheels as another group. Alternatively, the right front wheel and left rear wheel form one group, and the left front wheel and right rear wheel form another group. Brake pressure is supplied individually to these groups by a first actuator group comprising one or more actuators and a second actuator group comprising one or more actuators. When a fault occurs in an actuator in the first actuator group, the first actuator group is controlled so as not to generate brake pressure, and when a fault occurs in an actuator in the second actuator group, the second actuator group is controlled so as not to generate brake pressure. In this way, unbalance of braking force on the left and right wheels due to a fault in an actuator is prevented, and turning of the vehicle due to this unbalance is suppressed.
    Type: Grant
    Filed: August 7, 1998
    Date of Patent: May 15, 2001
    Assignee: Nissan Motor Co., Ltd.
    Inventor: Masahiro Tsukamoto
  • Patent number: 6036617
    Abstract: A speed ratio of a continuously variable transmission is varied according to an oil pressure which is adjusted by a valve driven by a step motor. The step motor is feedback controlled so that a real speed ratio coincides with a target speed ratio determined according to the running conditions of a vehicle. By determining a feedback gain based on the oil pressure, oil temperature, real speed ratio and output shaft rotation speed of the transmission, precise control of the speed ratio according to the running state is realized.
    Type: Grant
    Filed: November 13, 1998
    Date of Patent: March 14, 2000
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Hitoshi Kidokoro, Itsuro Muramoto, Masahiro Tsukamoto
  • Patent number: 5984435
    Abstract: A brake control system is comprised of a vehicle environment recognition device for obtaining vehicle environment including a road condition, an actuator for applying hydraulic pressure set at a target value to each wheel cylinder, and a controller for calculating the target value on the basis of the vehicle environment. The controller controls the wheel cylinder pressure by driving the actuator so as to adjusting the wheel cylinder pressure at the target value. Therefore, it becomes possible to ensure the same braking distance by the same depression degree of the brake even in various road conditions.
    Type: Grant
    Filed: March 27, 1997
    Date of Patent: November 16, 1999
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Masahiro Tsukamoto, Hiroshi Takahashi, Katsunori Oshiage
  • Patent number: 5885185
    Abstract: A first and a second power roller supported by trunnions are gripped between an input disc and an output disc disposed on an identical rotation axis. The gyration angles of the power rollers are varied by driving the trunnions in a direction perpendicular to the rotation axis by an oil pressure actuator. The oil pressure of the actuator is controlled based on a target gyration angle, and the gyration angle of the first power roller is fed back to the oil pressure control. Vibration of the first power roller due to external disturbance is prevented from affecting the second power roller via oil pressure control by making a force according to a displacement of the first power roller in the direction perpendicular to the rotation axis, act only on the trunnion supporting the first power roller.
    Type: Grant
    Filed: September 12, 1997
    Date of Patent: March 23, 1999
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Hitoshi Kidokoro, Itsuro Muramoto, Masahiro Tsukamoto
  • Patent number: 5439278
    Abstract: An anti-lock braking system (ABS) pressure modulator is provided. The modulator includes a frame with a bore fluidly exposed to master cylinder and wheel cylinder connections and a check valve for preventing fluid communication from the master cylinder connection to the wheel cylinder connection vi the bore. A piston is slidably mounted within the bore and has a predetermined extreme position at which a stem of the piston opens the check valve. A power device is actuated by an ABS controller. A cam, moved by the power device, has a cam surface. The position of the piston is determined by the cam. A cam follower roller is connected with the piston to in contact with the cam surface. A one-way brake prevents rotation of the roller when the cam moves in one rotational direction to allow the piston to move away from the predetermined extreme position, but allowing the roller to roll over the cam surface when the cam moves in the opposite direction to move the piston toward the predetermined extreme position.
    Type: Grant
    Filed: August 11, 1994
    Date of Patent: August 8, 1995
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Masahiro Tsukamoto, Masamichi Matuda
  • Patent number: 5433514
    Abstract: A pressure control actuator suitable for an automotive brake control system comprises a pressure-regulation cylinder slidably enclosing a piston and cooperative with the piston for defining therein a variable-volume pressure chamber which is fluidly connected to a wheel cylinder, a shut-off valve through which the variable-volume chamber is connected to a master cylinder, a motor-driven thrust generator drivingly connected to the piston for producing a thrust, and a heavily pre-loaded return spring for biasing the piston in a first direction opposite to a second direction in which the piston is pushed by the master-cylinder pressure shut-up in the chamber, when the piston is displaced apart from its neutral position in the second direction so that the volume of the chamber is enlarged. A pre-load of the spring is set to balance with a force acting on the piston by a maximum master-cylinder pressure introduced into the chamber.
    Type: Grant
    Filed: March 11, 1994
    Date of Patent: July 18, 1995
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Masahiro Tsukamoto, Takayuki Watanabe
  • Patent number: 5328257
    Abstract: A hydraulic brake actuator for use in an automobile brake system which includes a master cylinder to be operated by a driver and a wheel cylinder connected to the master cylinder through a hydraulic circuit for applying a braking force to a wheel. The actuator is capable of performing anti-skid control function and/or traction control function, and includes a control cylinder device having a chamber which is connected to the wheel cylinder and adapted to be selectively connected to the master cylinder and disconnected therefrom. A piston is axially displaceably accommodated in the chamber for changing the volume of the chamber. A valve device has inlet and outlet ports connected to the master cylinder and the chamber, respectively, and is operatively connected to the piston so as to be opened or closed in response to the displacement of the piston.
    Type: Grant
    Filed: April 23, 1992
    Date of Patent: July 12, 1994
    Assignee: Nissan Motor Co., Ltd.
    Inventor: Masahiro Tsukamoto
  • Patent number: 5233834
    Abstract: A piezo-actuator's displacement magnifying mechanism includes a first cylinder and a second cylinder which is smaller in diameter than the first cylinder and communicates with the same. A plunger is slidably mounted in the first cylinder. The plunger is moved by a piezo-actuator in the first cylinder when a predetermined voltage is applied to the piezo-actuator to cause the same to expand and contract. A piston is slidably mounted in the second cylinder. A reservoir is communicating with the first cylinder. A hydraulic fluid is received in the first and the second cylinder and the reservoir. The hydraulic fluid is variable in viscosity in response to electric fields to which the fluid is subjected. A fluid passage is provided between the first cylinder and the reservoir for compensating for thermal expansion/contraction of the fluid. An electrode is provided for subjecting the hydraulic fluid to electric fields in the passage according to an instruction for applying the voltage to the piezo-actuator.
    Type: Grant
    Filed: October 24, 1991
    Date of Patent: August 10, 1993
    Assignee: Nissan Motor Company, Ltd.
    Inventor: Masahiro Tsukamoto
  • Patent number: 5160161
    Abstract: An active suspension system for an automotive vehicle is provided. This suspension system includes generally a hydraulic circuit which supplies pressurized fluid to hydraulic cylinders for controlling vehicle height and attitude. The hydraulic circuit includes a line pressure holding unit and a line pressure control unit. The line pressure holding unit is operable to hold the line pressure when the line pressure is lowered below a preselected pressure level after stopping supply of the pressurized fluid to the hydraulic cylinders. The line pressure control unit restricts a flow rate of the pressurized fluid to the hydraulic cylinders to build up the line pressure gradually until the line pressure reaches the preselected pressure level after starting the supply of pressurized fluid to the hydraulic cylinders to allow smooth adjustment of vehicle height and attitude.
    Type: Grant
    Filed: February 21, 1991
    Date of Patent: November 3, 1992
    Assignee: Nissan Motor Company, Limited
    Inventors: Masahiro Tsukamoto, Kazunobu Kawabata
  • Patent number: 5156645
    Abstract: An active suspension system is provided with a pressure accumulator connected to a drain line connecting a drain port of a pressure control valve which controls pressure in the working chamber of an active cylinder. The pressure accumulator serves to absorb high pressure surge. A surge pressure absorbing unit is provided for feeding back the surge pressure generated in the drain line to the pressure accumulator via a supply line so that the surge pressure can be successfully absorbed by the pressure accumulator.
    Type: Grant
    Filed: April 27, 1990
    Date of Patent: October 20, 1992
    Assignee: Nisson Motor Company, Limited
    Inventors: Masahiro Tsukamoto, Hideki Tsuchiya
  • Patent number: 5055341
    Abstract: A composite molded article made of a nonwoven fibrous mat wherein inorganic monofilaments having a length of 10 to 200 mm and a diameter of 2 to 30 micrometers are partially bonded with a thermoplastic resin binder, may voids being provided throughout the mat and a large number of fine holes communicating with the voids in the inside being formed in at least one surface of the mat; and processes for producing the same.
    Type: Grant
    Filed: February 27, 1990
    Date of Patent: October 8, 1991
    Assignee: Sekisui Kagaku Kogyo Kabushiki Kaisha
    Inventors: Katsuhiko Yamaji, Masahiko Ishida, Masahiro Tsukamoto
  • Patent number: 5054808
    Abstract: An active suspension system is provided a pressure accumulator connected to a drain line connecting a drain port of a pressure control valve which controls pressure in the working chamber of an active cylinder. The pressure accumulator serves for absorbing high pressure surge. On the other hand, means, disposed within the drain line, for generating pressure difference between the upstream and the lowerstream thereof so that the fluid pressure in the drain line at the orientation where the pressure accumulator is connected, is maintained at a level higher than an initial gas pressure in the pressure accumulator.
    Type: Grant
    Filed: April 27, 1990
    Date of Patent: October 8, 1991
    Assignee: Nissan Motor Company, Limited
    Inventor: Masahiro Tsukamoto
  • Patent number: 5042832
    Abstract: A proportioning valve assembly has a supply port through which a pressurized working fluid is supplied, a drain port through which a pressurized working fluid is drained, and a control port connected to a working chamber defined in a hydraulic cylinder disposed between a vehicular body and a suspension member rotatably supporting a vehicular wheel. The proportioning valve assembly further includes a valve member for adjusting working fluid pressure to be supplied to the working chamber via the control port. A flow restricting orifice is provided in the proportioning valve assembly. The flow restricting orifice employed is designed to provide variable flow restriction depending upon working fluid condition and/or the direction for achieving stabilization of pilot pressure or road shock absorption.
    Type: Grant
    Filed: January 27, 1989
    Date of Patent: August 27, 1991
    Assignee: Nissan Motor Company, Limited
    Inventors: Kenro Takahashi, Naohiko Inoue, Masahiro Tsukamoto
  • Patent number: 4982979
    Abstract: A hydraulic circuit for an active suspension system employs a pressure accumulator connected to a drain line at an orientation upstream of a pilot operated operational one-way check valve. The pressure accumulator absorbs back pressure generated in the drain line due to flow resistance in the drain line.
    Type: Grant
    Filed: December 26, 1989
    Date of Patent: January 8, 1991
    Assignee: Nissan Motor Company, Limited
    Inventors: Yohsuke Akatsu, Naoto Fukushima, Yukio Fukunaga, Itaru Fujimura, Masaharu Satoh, Kensuke Fukuyama, Kenro Takahashi, Masahiro Tsukamoto
  • Patent number: 4973079
    Abstract: An actively controlled suspension system includes a fluid circuit connecting a fluid pressure source and a working chamber of a working cylinder disposed between a vehicle body and a suspension member. The fluid circuit includes a pressure control valve which is connected to an electric control system to be controlled valve position by an electric control signal for controlling fluid pressure in the working chamber. The fluid circuit also includes a fail-safe valve which normally forms part of fluid path of the fluid circuit is responsive to a fail-safe signal generated in the control system to take place fail-safe operation for setting the fluid pressure in the working chamber at a predetermined pressure.
    Type: Grant
    Filed: February 15, 1989
    Date of Patent: November 27, 1990
    Assignee: Nissan Motor Company, Limited
    Inventor: Masahiro Tsukamoto
  • Patent number: 4948165
    Abstract: A proportioning valve assembly employs an electromagnetic acuator, such as a proportioning solenoid, associated with a driver circuit. The driver circuit is provided a lead phase circuit for providing a lead phase in supplying a supply current for controlling the valve position of the proportioning valve. Providing appropriate lead time reduces necessity of high gain in attitude change suppression mode operation. Therefore, the response characteristics in pressure adjustment in the shock absorbing mode operation, can be prevented from falling an excessive level.
    Type: Grant
    Filed: January 26, 1989
    Date of Patent: August 14, 1990
    Assignee: Nissan Motor Company, Limited
    Inventors: Kenro Takahashi, Naohiko Inoue, Masahiro Tsukamoto
  • Patent number: 4923547
    Abstract: A composite molded article made of a nonwoven fibrous mat wherein inorganic monofilaments having a length of 10 to 200 mm and a daimeter of 2 to 30 micrometers are partially bonded with a thermoplastic resin binder, many voids being provided throughout the mat and a large number of fine holes communicating with the voids in the inside being formed in at least one surface of the mat; and processes for producing the same.
    Type: Grant
    Filed: August 17, 1988
    Date of Patent: May 8, 1990
    Assignee: Sekisui Kagaku Kogyo Kabushiki Kaisha
    Inventors: Katsuhiko Yamaji, Masahiko Ishida, Masahiro Tsukamoto
  • Patent number: 4919440
    Abstract: An actively controlled suspension system includes a fail-safe system which is associated with a pressure control valve and detective of failure of a control circuit to perform fail-safe operation. The fail-safe system operates the pressure control valve in response to failure of the control circuit, to fix the valve position corresponding to a working fluid pressure in a working chamber defined in a suspension cylinder disposed between a vehicular body and a suspension member rotatably supporting a vehicular wheel, at a pressure value at or in the vicinity of a predetermined initial or neutral pressure.
    Type: Grant
    Filed: November 29, 1988
    Date of Patent: April 24, 1990
    Assignee: Nissan Motor Company, Limited
    Inventor: Masahiro Tsukamoto
  • Patent number: 4834313
    Abstract: An emergency locking retractor is constructed of a base having an engaged portion; a take-up spindle supported displaceably in a direction perpendicular to the longitudinal central axis thereof; a movable member supported rotatably about the spindle; a holder for normally holding the movable member unrotatably; a clutch mechanism for connecting the spindle and the movable member to each other when the spindle undergoes a rotational speed change; a ratchet member provided as a unitary member with the spindle, said ratchet member being engageable with the engaged portion to prevent any further rotation of the spindle when a tensile force is applied to the spindle and the spindle is displaced in the direction perpendicular to the longitudinal central axis thereof; and a clutch mechanism releasing device for causing the movable member to turn in a webbing-releasing direction when the ratchet member and engaged portion are in mutual engagement.
    Type: Grant
    Filed: December 3, 1987
    Date of Patent: May 30, 1989
    Assignee: Nippon Seiko Kabushiki Kaisha Corp.
    Inventor: Masahiro Tsukamoto