Patents by Inventor Mitsuo Sasaki

Mitsuo Sasaki 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: 6098765
    Abstract: A rotary damper includes: a pressure generating mechanism portion A for relatively pivoting swingable vanes 4a and 4b with respect to stationary vanes 2a and 2b located on a casing 1 so as to vary reverse proportionally a pressure of a fluid filled within two pressure chambers 5a, 5b, 6a, and 6b; and a damping force generating mechanism portion B which limits a movement of the fluid based on a pressure variation generation at the pressure generating mechanism portion A to generate the damping force. A first transmission mechanism portion C and a second transmission mechanism portion D are interposed between both mechanism portions A and B, each of the first and second transmission mechanism portions C and D being capable of moving the fluid and transmitting the fluid pressure via movable first bellows 12 and second bellows 13.
    Type: Grant
    Filed: December 17, 1998
    Date of Patent: August 8, 2000
    Assignee: Unisia Jecs Corporation
    Inventors: Hiroshi Kato, Mitsuo Sasaki, Fumiyuki Yamaoka
  • Patent number: 5983150
    Abstract: A method of controlling a suspension system include sensing a behavior of a motor vehicle, producing a control signal in accordance with the behavior sensed, carrying out normal control of a damping-force characteristic of a shock absorber in accordance with the control signal produced and based on a predetermined damping-force characteristic curve, determining a brake operating state, determining a frictional coefficient of a road surface, determining a frequency input from the road surface, and reducing variations in a load of a wheel by controlling the damping-force characteristic of the shock absorber in accordance with the brake operating state, frictional coefficient, frequency determined.
    Type: Grant
    Filed: August 7, 1998
    Date of Patent: November 9, 1999
    Assignee: Unisia Jecs Corporation
    Inventor: Mitsuo Sasaki
  • Patent number: 5950776
    Abstract: An apparatus and method for controlling damping force characteristics of respective vehicular shock absorbers in which vehicular vertical behavior(s) at the position(s) of the vehicular body which are forward by a predetermined distance from a tread of rear left and right road wheels are determined, the positions including front left and right road wheel sides, and corresponding vertical behavior signals are derived. Control signals for front left and right and rear left and right road wheel side shock absorbers are formed on the basis of respective processed signals having frequency-dependent characteristics formed from the vehicular behavior signal(s). The damping force characteristics of front left and right road wheel side shock absorbers are controlled on the basis of the control signals formed on the basis of the processed signal based on the front left and right road wheel vehicular behavior signals.
    Type: Grant
    Filed: July 30, 1998
    Date of Patent: September 14, 1999
    Assignee: Unisia Jecs Corporation
    Inventors: Katsuya Iwasaki, Mitsuo Sasaki
  • Patent number: 5911768
    Abstract: A suspension control apparatus for use with shock absorbers provided between sprung and unsprung masses of the vehicle at the respective road wheel positions for providing variable damping force characteristics. A control unit receives first sensor signals indicative of sensed vehicle sprung mass vertical behaviors for controlling the shock absorbers to have respective target damping force characteristics determined based on the vehicle sprung mass vertical behaviors. A surface condition of a road on which the vehicle is running is determined based on the first sensor signals. The control unit also receives a second sensor signal indicative of a sensed vehicle lateral acceleration for detecting vehicle steering operation. The second sensor signal is compared with a reference value. Vehicle steering operation is detected in response to a result of comparison of the second sensor signal with the reference value.
    Type: Grant
    Filed: October 18, 1996
    Date of Patent: June 15, 1999
    Assignee: Unisia Jecs Corporation
    Inventor: Mitsuo Sasaki
  • Patent number: 5890081
    Abstract: A suspension control system for use with shock absorbers provided between sprung and unsprung masses of an automotive vehicle at the positions of the respective vehicle road wheels for providing variable damping force characteristics. Sprung mass vertical velocities at the respective road wheel positions are derived from a sensed sprung mass vertical behavior. Relative velocities between the sprung and unsprung masses at the respective road wheel positions are derived from the sensed sprung mass vertical behavior with the use of a predetermined transfer function including terms related to damping coefficients of the respective shock absorbers. A control unit is provided for producing control signals based on the derived sprung mass vertical velocities and the derived relative velocities to control the damping force characteristics of the respective shock absorbers. Damping coefficients of the respective shock absorbers are determined based on the corresponding control signals.
    Type: Grant
    Filed: July 8, 1996
    Date of Patent: March 30, 1999
    Assignee: Unisia Jecs Corporation
    Inventor: Mitsuo Sasaki
  • Patent number: 5832398
    Abstract: In apparatus and method for controlling a damping force characteristic of each of front and rear left and right road wheel positioned shock absorbers based on a Sky Hook control theory, rear left and right road wheel position vehicular behaviors are estimated using a predetermined transfer function established between front road wheel position vehicular behaviors and rear road wheel position vehicular behaviors from front left and right road wheel position vehicular behavior related signals with the damping force characteristics of the rear road wheel positioned shock absorbers controlled on the basis of rear road wheel position control signals formed for the rear left and right road wheel positioned shock absorbers on the basis of the estimated rear road wheel position vehicular behaviors.
    Type: Grant
    Filed: October 9, 1997
    Date of Patent: November 3, 1998
    Assignee: Unisia Jecs Corporation
    Inventors: Mitsuo Sasaki, Katsuya Iwasaki
  • Patent number: 5826381
    Abstract: A three-dimensional structure adapted to be assembled dissociably and placed on a substantially flat surface is disclosed. This structure includes a plurality of upright support members each integrally molded from concrete, the upright support members each including a base portion extending horizontally with a predetermined width, and being to be placed on the surface; and an upright portion extending upwardly from the base portion, and having opposite side surfaces defining a widthwise thickness and opposite end surfaces defining a horizontal length. These upright support members are spaced from each other in a horizontally transverse direction and a horizontally longitudinal direction. Transversely adjacent upright support members are connected together by beam means, while longitudinally adjacent upright support members are connected together by connecting means.
    Type: Grant
    Filed: June 28, 1996
    Date of Patent: October 27, 1998
    Inventor: Mitsuo Sasaki
  • Patent number: 5818193
    Abstract: A step motor driving method employing an electric circuit operable on a supply voltage applied thereto for generating a step drive signal having a variable on-duty ratio to drive the step motor. A PWM control is made to change the step drive signal on-duty ratio. The the step drive signal on-duty ratio is increased to compensate for a supply voltage drop.
    Type: Grant
    Filed: October 17, 1995
    Date of Patent: October 6, 1998
    Assignee: Unisia Jecs Corporation
    Inventor: Mitsuo Sasaki
  • Patent number: 5810384
    Abstract: An apparatus and method for controlling damping force characteristics of respective vehicular shock absorbers in which vehicular vertical behavior(s) at the position(s) of the vehicular body which are forward by a predetermined distance from a tread of rear left and right road wheels are determined, the positions including front left and right road wheel sides, and corresponding vertical behavior signals are derived. Control signals for front left and right and rear left and right road wheel side shock absorbers are formed on the basis of respective processed signals having frequency-dependent characteristics formed from the vehicular behavior signal(s). The damping force characteristics of front left and right road wheel side shock absorbers are controlled on the basis of the control signals formed on the basis of the processed signal based on the front left and right road wheel vehicular behavior signals.
    Type: Grant
    Filed: February 4, 1997
    Date of Patent: September 22, 1998
    Assignee: Unisia Jecs Corporation
    Inventors: Katsuya Iwasaki, Mitsuo Sasaki
  • Patent number: 5808890
    Abstract: In apparatus and method for controlling a damping force characteristic for a vehicular suspension system, a relative velocity between a sprung mass and an unsprung mass is calculated using a predetermined transfer function from a sprung mass vertical velocity derived on the basis of a sprung mass acceleration signal. The predetermined transfer function is, in a embodiment, expressed as G.sub.U(S) =(QS.sup.2 +RS)/(FS.sup.2 +DS +E), wherein Q=-m.sub.1 .multidot.c.sub.2, R=-m.sub.1 .multidot.k.sub.2, F=c.sub.1 .multidot.c.sub.2, D=c.sub.1 .multidot.k.sub.2, E=k.sub.1 .multidot.k.sub.2, S denotes a Laplace operator, c.sub.1 denotes an attenuation constant of each shock absorber, c.sub.2 denotes an attenuation constant of the corresponding one of road wheels, k.sub.1 denotes a spring constant of the shock absorber. k.sub.2 denotes a spring constant of the corresponding one of the road wheels, m.sub.1 denotes the sprung mass, and m.sub.2 denotes the unsprung mass.
    Type: Grant
    Filed: September 29, 1995
    Date of Patent: September 15, 1998
    Assignee: Unisia Jecs Corporation
    Inventor: Mitsuo Sasaki
  • Patent number: 5794168
    Abstract: In apparatus and method for controlling a damping force characteristic of each of front and rear left and right road wheel positioned shock absorbers based on a Sky Hook control theory, rear left and right road wheel position vehicular behaviors are estimated using a predetermined transfer function established between front road wheel position vehicular behaviors and rear road wheel position vehicular behaviors from front left and right road wheel position vehicular behavior related signals with the damping force characteristics of the rear road wheel positioned shock absorbers controlled on the basis of rear road wheel position control signals formed for the rear left and right road wheel positioned shock absorbers on the basis of the estimated rear road wheel position vehicular behaviors.
    Type: Grant
    Filed: October 10, 1995
    Date of Patent: August 11, 1998
    Assignee: Unisia Jecs Corporation
    Inventors: Mitsuo Sasaki, Katsuya Iwasaki
  • Patent number: 5781873
    Abstract: In apparatus and method for controlling a damping force characteristic for a vehicular suspension system, a control force (F) based on an ideal Sky Hook theory is generated even when a low responsive characteristic and less expensive actuator such as a stepping motor associated with an adjuster of each shock absorber and which is not enabled to respond to an unsprung mass resonance frequency and a control signal based on a sprung mass vertical velocity and on a relative velocity between a vehicle body (sprung mass) and a road wheel assembly (unsprung mass) is formed using a signal processing circuit so that the control signal is formed in a low frequency band. The damping force characteristic of each shock absorber is controlled on the basis of the formed control signal.
    Type: Grant
    Filed: September 29, 1995
    Date of Patent: July 14, 1998
    Assignee: Unisia Jecs Corporation
    Inventor: Mitsuo Sasaki
  • Patent number: 5638275
    Abstract: In an apparatus and method for controlling damping forces of vehicular shock absorbers, at least one of pitch rate or roll rate of the vehicle is derived on the basis of output signals from at least three of wheel speed sensors located on front road wheels and located on either of rear right and left road wheels.
    Type: Grant
    Filed: February 24, 1995
    Date of Patent: June 10, 1997
    Assignee: Unisia Jecs Corporation
    Inventors: Mitsuo Sasaki, Hiroyuki Yamaguchi, Takeshi Fuchida
  • Patent number: 5627443
    Abstract: A method of driving a stepping motor comprises dividing a drive signal for each drive step into a plurality of portions in the direction of a time axis, and controlling the drive signal in connection with the plurality of portions thereof in a way of PWM so as to obtain a pattern of a gradual change in a on-duty ratio of the drive signal.
    Type: Grant
    Filed: March 31, 1995
    Date of Patent: May 6, 1997
    Assignee: Unisia Jecs Corporation
    Inventors: Makoto Kimura, Junichi Emura, Shinobu Kakizaki, Mitsuo Sasaki
  • Patent number: 5616349
    Abstract: A movable slab form unit is provided and has a movable base plate, a slab form, an elevation motion device that connects the slab form to the base plate while maintaining the freedom of being raised and lowered, and a stabilizer device for stabilizing the elevation motion device into a predetermined state. The elevation motion device includes a first link which is pivotably coupled at its lower ends to the base plate, a second link which is coupled at its lower ends to the base plate so as to move along the base plate and a coupling pin for pivotably coupling the first link and second link together. The stabilizer means includes a support rod of which the length can be adjusted, and is pivotably coupled at its one end to the second link and is detachably engaged at its other end with an engaging portion provided on the base plate.
    Type: Grant
    Filed: January 12, 1995
    Date of Patent: April 1, 1997
    Inventor: Mitsuo Sasaki
  • Patent number: 5590863
    Abstract: A support including a support pipe having a pair of elongated holes formed therein, a support ring, an insertion pipe having plural pairs of pin holes formed therein, and a support pin. The support ring includes a main support ring member having an internal thread formed in the inner peripheral portion thereof and an upper support ring member rotatably coupled to the upper end portion of the main support ring member via an upper thrust bearing. A rotary operation handle is fitted to the outer peripheral portion of the main support ring member.
    Type: Grant
    Filed: October 31, 1994
    Date of Patent: January 7, 1997
    Inventor: Mitsuo Sasaki
  • Patent number: 5572426
    Abstract: In an apparatus and method for controlling a damping force characteristic of a vehicular shock absorber, a vertical sprung mass velocity signal V.sub.n is determined on the basis of a vertical G sensor output signal as a control signal. A control gain when a control unit changes a damping force characteristic of either an extension stroke side or a compression stroke side of a piston member of the shock absorber according to the control signal is increased as a moving average of peak values of the vertical sprung mass velocity signal V.sub.n is reduced.
    Type: Grant
    Filed: September 12, 1994
    Date of Patent: November 5, 1996
    Assignees: Unisia Jecs Corporation, Nissan Motor Co., Ltd.
    Inventors: Mitsuo Sasaki, Toshiro Hirai
  • Patent number: 5526262
    Abstract: A suspension control system for an automotive vehicle is provided. This suspension control system comprises variable damping force shock absorbers and a control unit which controls the shock absorbers to assume damping force characteristics in a range between preselected higher and lower damping coefficients. The control unit is operable to provide a control parameter indicative of bouncing motion of a vehicle body based on sprung vertical speed to determine a damping coefficient against the bouncing motion. When the control parameter is greater than a threshold value, the damping coefficient is modified to a lower value, while when the control parameter is less than the threshold value, the damping coefficient is modified to a higher value. With this damping coefficient modification, the bouncing motion is suppressed effectively while assuring passenger comfort.
    Type: Grant
    Filed: December 24, 1992
    Date of Patent: June 11, 1996
    Assignee: Atsugi Unisia Corporation
    Inventors: Makoto Kimura, Fumiyuki Yamaoka, Shinobu Kakizaki, Toru Takahashi, Mitsuo Sasaki
  • Patent number: 5515273
    Abstract: A system and method for controlling a damping characteristic of at least one shock absorber for an automotive vehicle in which, when direction determining signs of both vertical sprung mass velocity (V) and relative velocity (Sv) between a sprung mass and an unsprung mass are the same, the variable control of the damping characteristic C is carried out at either of extension stroke side (V is plus and Sv is plus) or contraction stroke side (V is minus and Sv is minus) to provide C=.alpha..multidot.V/Sv, and when the direction determining signs of both vertical sprung mass velocity (V) and relative velocity (Sv) between the sprung mass and the unsprung mass are mutually different, the variable control of the damping characteristic C is carried out at either of extension stroke side (V is plus and Sv is minus) or contraction stroke side (V is minus and Sv is plus) to provide C=.alpha..multidot.V.
    Type: Grant
    Filed: February 22, 1994
    Date of Patent: May 7, 1996
    Assignee: Unisia Jecs Corporation
    Inventors: Mitsuo Sasaki, Makoto Kimura
  • Patent number: 5488556
    Abstract: An apparatus and method for controlling damping force characteristics of shock absorbers independently of one another, the damping force coefficient for each shock absorber being controlled on the basis of so-called "sky hook" theory with respective sprung mass vertical velocities and relative velocities between the sprung mass and unsprung mass taken into consideration. The relative velocity detecting sensors are only installed on portions of the vehicle related to front left and right tire wheels. The road surface velocities on the front left and right tire wheels are calculated and the road surface velocities on the rear left and right tire wheels are calculated on the basis of the calculated front left and right wheel road surface velocities, a vehicular wheel base length, and a vehicle speed.
    Type: Grant
    Filed: March 22, 1994
    Date of Patent: January 30, 1996
    Assignee: Unisia Jecs Corporation
    Inventor: Mitsuo Sasaki