Patents by Inventor Yoshihisa Yamamoto

Yoshihisa Yamamoto 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: 5931885
    Abstract: A control apparatus executes appropriate speed change control under any operating conditions encountered during an up-shift by change-over, without requiring an increase in control logic. Engagement side hydraulic pressure is swept up as a result of an arithmetic operation in torque phase speed change control. Disengagement side hydraulic pressure is calculated by initial speed change control, dependent on the engagement side hydraulic pressure. The engagement side hydraulic pressure is directly controlled and the disengagement side hydraulic pressure is indirectly controlled, i.e. responsive to the engagement side control. Consequently, the same control scheme can be executed regardless of power-on state or power-off state and regardless of vehicle operating conditions.
    Type: Grant
    Filed: April 30, 1997
    Date of Patent: August 3, 1999
    Assignee: Aisin AW Co., Ltd.
    Inventors: Takayuki Kubo, Masaaki Nishida, Yoshihisa Yamamoto, Akitomo Suzuki, Hiroshi Tsutsui, Kazumasa Tsukamoto
  • Patent number: 5931761
    Abstract: In a driven state, a hydraulic pressure of disengagement side is set at a stroke pressure, a one-way clutch in an operating state is over-run, an engine rotation speed is in an idle state, and an automatic transmission is in a neutral state. In a drive state, the hydraulic pressure of disengagement side is controlled so that a difference between an engine rotation speed and an input rotation speed reaches a difference between the both rotation speeds at a start of the shift control. In a state of a synchronized rotation after the shift, the hydraulic pressure of disengagement side is controlled so that the input rotation reaches the synchronized rotation.
    Type: Grant
    Filed: January 14, 1998
    Date of Patent: August 3, 1999
    Assignee: Aisin AW Co., Ltd.
    Inventors: Hiroshi Tsutsui, Masaaki Nishida, Yoshihisa Yamamoto, Akitomo Suzuki, Takayuki Kubo
  • Patent number: 5924958
    Abstract: If a shift to the 3rd speed is decided during the 5th-4th speed shift, in which the hydraulic servo for a second clutch is released by pressure regulation control, a changeover valve is switched by a solenoid valve so that the fluid pressure P.sub.C2 from the pressure regulating valve is conducted to a third clutch hydraulic servo. Thereby, the third clutch hydraulic servo pressure P.sub.C3 stands by at a predetermined engaging pressure P.sub.H and, at the same time, the servo-start of a fourth brake fluid pressure P.sub.B4 is performed by another pressure regulating valve. Meanwhile, the fluid pressure P.sub.C2 is released by an accumulator. After the servo-start ends and the 4th speed is established, the 4-3 speed shift control is performed, thus preventing shift shock and reducing shift duration.
    Type: Grant
    Filed: April 18, 1997
    Date of Patent: July 20, 1999
    Assignee: Aisin AW Co., Ltd.
    Inventors: Saoto Tsuchiya, Masaaki Nishida, Yoshihisa Yamamoto, Akitomo Suzuki, Hiroshi Tsutsui
  • Patent number: 5911646
    Abstract: When a vehicle is halted with the transmission in a forward drive range, an input clutch is disengaged to enhance the fuel efficiency and, at the same times a hill-hold brake is engaged to prevent the vehicle from rolling backward on a steep up-slope. At that time, the hydraulic pressure P.sub.C-1 of the input clutch C1 is gradually reduced by .DELTA.P.sub.CIR (P.sub.C-1 =P.sub.C-1 -.DELTA.P.sub.CIR) while the hydraulic pressure P.sub.B-1 of the hill-hold brake B1 is increased gradually so as to satisfy an equation P.sub.B-1 =K1+K2 X e where .DELTA.P.sub.cir is a change in hydraulic pressure which is required for gradually disengaging the first clutch C1, K1 is a hill-hold brake pressure at which braking resistance begins, K2 is hill-hold brake pressure producing a fully braked condition, and e is the input/output rotational-speed ratio of a torque converter Subsequently during start of vehicle movement, the hydraulic pressure P.sub.C-1 of the input clutch C1 is gradually increased (P.sub.C-1 =p.sub.C-1 +.
    Type: Grant
    Filed: December 30, 1996
    Date of Patent: June 15, 1999
    Assignee: Aisin Aw Co., Ltd.
    Inventors: Hiroshi Tsutsui, Kazumasa Tsukamoto, Masahiro Hayabuchi, Masaaki Nishida, Yoshihisa Yamamoto, Akitomo Suzuki
  • Patent number: 5908370
    Abstract: In power-on, high-vehicle-speed and high-torque conditions, a control unit sets a torque allotment ratio such that a main clutch bears all the torque. Thereby, the input shaft rotational speed is increased by controlling solely the main clutch releasing pressure. In power-on and low-torque or low-vehicle-speed conditions, the control unit sets a torque allotment ratio for the main clutch torque and the sub-clutch torque to 1:1. Thereby, control of the main clutch releasing pressure and control of the sub-clutch engaging pressure simultaneously proceed in parallel to produce a change in the input shaft rotational speed without a time lag. The hydraulic control apparatus thus conducts proper downshift control for a shift involving clutch engagement changeover, under all vehicle running conditions, without need for additional control logic.
    Type: Grant
    Filed: April 25, 1997
    Date of Patent: June 1, 1999
    Assignee: Aisin AW Co., Ltd.
    Inventors: Takayuki Kubo, Masaaki Nishida, Yoshihisa Yamamoto, Akitomo Suzuki, Hiroshi Tsutsui, Kazumasa Tsukamoto
  • Patent number: 5902213
    Abstract: In an automatic transmission including a gear unit with a second brake connected in series with a one-way clutch and a first brake that is not connected with a one-way clutch, the second brake and the first brake are controlled by linear solenoid valves individually. A vehicle load is detected, and when the vehicle is in a high load state, at first the second brake performs an engagement control, then after input rotation to the gear unit is synchronized with output rotation of the gear unit, the first brake performs an engagement control. When the vehicle is in a low load state, at first the first brake performs an engagement control, then after input rotation to the gear unit is synchronized with output rotation of the gear unit, the second brake performs an engagement control.
    Type: Grant
    Filed: December 22, 1997
    Date of Patent: May 11, 1999
    Assignee: Aisin AW Co., Ltd.
    Inventors: Hiroshi Tsutsui, Masaaki Nishida, Yoshihisa Yamamoto, Akitomo Suzuki
  • Patent number: 5899758
    Abstract: A memory card connector with an ejection mechanism 10 comprises an operating rod 15 sliding lengthwise along a side surface of a frame 11 and a cam bar 16 linked to the operating rod 15 intended for the ejection of the card. A spring 17 is attached to an overhang at an inner end of the operating rod 15 and to a mounting member 19 on the frame 11. Because of such an arrangement, the operating rod 15 is forced forward; and at the same time, due to the fact that the mounting member 19 is closer to the center of the connector than an overhang 34 of the operating rod 15, the operating rod is forced to the side surface of the frame 11.
    Type: Grant
    Filed: September 23, 1997
    Date of Patent: May 4, 1999
    Assignee: The Whitaker Corporation
    Inventors: Yoshihisa Yamamoto, Hiroshi Kojima
  • Patent number: 5891538
    Abstract: A thermoplastic resin composition comprising (i) 5 to 80% by weight of a polyamide resin, (ii) 15 to 90% by weight of a fluororesin and (iii) 1 to 80% by weight of a fluororubber having a tensile modulus at ordinary temperature of not more than 500 Kg/cm.sup.2, and a laminated material having a layer formed from the thermoplastic resin composition have excellent chemical resistance.
    Type: Grant
    Filed: April 29, 1996
    Date of Patent: April 6, 1999
    Assignee: Baikin Industries, Ltd.
    Inventors: Yoshihisa Yamamoto, Takafumi Yamato, Tetsuo Shimizu, Takeshi Harada
  • Patent number: 5877509
    Abstract: A light emitting device made of semiconducting materials. The device has an optical microcavity which supports a resonant mode of predetermined photon energy. Within the cavity is a quantum well of predetermined thickness and energy depth. The quantum well is designed such that it forms bound electron, exciton, lower polariton, and hole energy states of predetermined energy. The energy of an exciton state is set to equal the predetermined photon energy of the microcavity mode such that polariton states are created. A means is provided for resonantly tunneling electrons into a quantum well energy state. In a first embodiment, electrons resonantly tunnel into an electron energy state. In a second embodiment, electrons resonantly tunnel into an exciton energy state, during which tunneling the electrons simultaneously fuse with holes to form excitons.
    Type: Grant
    Filed: November 14, 1997
    Date of Patent: March 2, 1999
    Assignees: Stanford University, Japan Science and Technology Corporation
    Inventors: Stanley Pau, Hui Cao, Yoshihisa Yamamoto
  • Patent number: 5869574
    Abstract: A thermoplastic resin composition comprising a blend obtainable by blending 0.1 to 99% by weight of (a) a fluorine-containing polymer having a number-average molecular weight of 2000 to 1000000 and having hydroxy group or epoxy group at least at one of end portions of a main chain and side chain of the polymer, and 1 to 99.9% by weight of (b) a heat resisting thermoplastic resin having a crystalline melting point or glass transition temperature of not less than 150.degree. C. The present invention can provide a composition comprising various heat resisting thermoplastic resins and a fluorine-containing polymer having a functional group which is capable of developing an affinity with said resins and forming a uniform dispersion.
    Type: Grant
    Filed: April 17, 1997
    Date of Patent: February 9, 1999
    Assignee: Daikin Industries, Ltd.
    Inventors: Tetsuo Shimizu, Yoshihisa Yamamoto, Seitaro Yamaguchi, Nobuhiko Tsuda, Noriyasu Yamane, Takafumi Yamato, Masahiro Kumegawa, Takayuki Araki
  • Patent number: 5813943
    Abstract: A control system for an automatic transmission includes: a clutch adapted to be applied when a forward running range is selected, to transmit the rotation of an engine to the transmission mechanism of a speed change unit and a hydraulic servo for applying/releasing the clutch. A control unit controls oil pressure fed to the hydraulic servo and includes: an application starting pressure detector for detecting application starting pressure at the instant when the application of the clutch is started; an initial application pressure setter for setting an initial application pressure on the basis of the detected application starting pressure; and an oil pressure regulator for adjusting the oil pressure fed to the hydraulic servo, when a change is made to a forward running range, and then gradually raising that oil pressure.
    Type: Grant
    Filed: May 10, 1996
    Date of Patent: September 29, 1998
    Assignee: Aisin AW Co., Ltd.
    Inventors: Yuuki Kousaka, Masahiro Hayabuchi, Yoshihisa Yamamoto, Hiroshi Tsutsui, Yasuhiro Fujita
  • Patent number: 5803866
    Abstract: During transmission shifts, a band brake is used in either a self-loosening direction in which an engaging force thereof is not sensitive to variations in hydraulic pressure or a self-tightening direction in which the engaging force is sensitive to variations in hydraulic pressure. In the self-loosening direction, a second regulated hydraulic pressure generated by a second pressure regulating valve (B-4 control valve) in accordance with a control hydraulic pressure generated by a second (throttle-pressure-control) linear solenoid valve in a margin control region thereof is supplied to a hydraulic servo of the fourth brake (band brake). In this clutch-to-clutch shift, a first regulated hydraulic pressure generated by a first pressure regulating valve (a shift-pressure control valve) in accordance with a control hydraulic pressure generated by a first (pressure-regulation) linear solenoid valve is supplied to a hydraulic servo of a third (UD direct) clutch.
    Type: Grant
    Filed: December 30, 1996
    Date of Patent: September 8, 1998
    Assignee: Aisin AW Co., Ltd.
    Inventors: Kazumasa Tsukamoto, Masahiro Hayabuchi, Masaaki Nishida, Yoshihisa Yamamoto, Akitomo Suzuki
  • Patent number: 5800308
    Abstract: A control system for an automatic transmission operates a clutch for disengaging a transmission mechanism when a vehicle is stopped and idling with the brake pedal depressed while the gear shift is in a forward gear. The clutch is maintained at a drag state (friction elements disengaged but oil causing some torque transmission) bordering a slip state (friction elements engaged) When a neutral control is started, the clutch is released until the retraction of the piston of the hydraulic servo is started. When the rate of change in a rotational difference does not exceeds a reference rate of change even after a set time has elapsed, booster means of specific release state holding means decides that the clutch is in a drag region, and raises an oil pressure to be fed to the hydraulic servo, by a set pressure.
    Type: Grant
    Filed: May 13, 1996
    Date of Patent: September 1, 1998
    Assignee: Aisin AW Co., Ltd.
    Inventors: Hiroshi Tsutsui, Kazumasa Tsukamoto, Masahiro Hayabuchi, Masaaki Nishida, Yoshihisa Yamamoto
  • Patent number: 5788603
    Abstract: A control system for an automatic transmission operates a clutch in a speed change unit to disconnect a transmission mechanism from a fluid transmission unit during a neutral operating state while the vehicle in a forward gear is held stopped by braking with the throttle fully closed. Reengagement of the clutch such as by depression of accelerator pedal (throttle open), release of the brake pedal, etc., is produced by a gradual increase in oil pressure to the servo operating the clutch to prevent clutch application shock. Wear on the clutch is reduced by abrupt increase of the oil pressure in response to satisfaction of a clutch engagement completion condition based upon input RPM, output RPM and the gear ratio of the target gear.
    Type: Grant
    Filed: May 10, 1996
    Date of Patent: August 4, 1998
    Assignee: Aisin AW Co., Ltd.
    Inventors: Hiroshi Tsutsui, Yoshihisa Yamamoto, Masahiro Hayabuchi, Masaaki Nishida
  • Patent number: 5782711
    Abstract: A hydraulic pressure control apparatus for an automatic transmission including a microprocessor-based control unit for controlling hydraulic pressure supplied to hydraulic servos of friction engagement elements. The control apparatus calculates a target hydraulic pressure P.sub.TA for a condition at the start of the inertia phase in accordance with the input torque, and a gradient based on the target hydraulic pressure and a predetermined time t.sub.TA. A first up-sweep of hydraulic pressure is performed by the apparatus with the gradient. A relatively gradual gradient .delta.P.sub.TA is set based on a target rotation change rate for the input rotational speed to provide a predetermined change amount when the hydraulic pressure becomes the target hydraulic pressure P.sub.TA. The control apparatus performs a second up-sweep with the gradient .delta.P.sub.TA. When the rotational speed change .DELTA.N of the input rotation becomes a rotation change start-determining rotational speed dN.sub.
    Type: Grant
    Filed: December 18, 1996
    Date of Patent: July 21, 1998
    Assignee: Aisin AW Co., Ltd.
    Inventors: Hiroshi Tsutsui, Kazumasa Tsukamoto, Masahiro Hayabuchi, Masaaki Nishida, Yoshihisa Yamamoto, Toshihiro Kano, Takayuki Kubo, Saoto Tsuchiya
  • Patent number: 5779585
    Abstract: To achieve a predetermined speed by engaging or releasing friction engagement elements of an auxiliary shift mechanism, a fluid pressure changeover valve is switched to a position for communication between a regulated pressure input port and an output port, so that regulated fluid pressure from a pressure regulating valve is supplied through second shift mechanism-side shift valves to the friction engagement elements of the auxiliary shift mechanism to be engaged or released. This position switch of the changeover valve also connects a line pressure input port to an output port whereby line pressure is supplied to the main shift mechanism-side shift valves to maintain the main shift mechanism in a predetermined speed state.
    Type: Grant
    Filed: December 12, 1996
    Date of Patent: July 14, 1998
    Assignee: Aisin Aw Co., Ltd.
    Inventors: Kazumasa Tsukamoto, Masahiro Hayabuchi, Masaaki Nishida, Yoshihisa Yamamoto, Akitomo Suzuki
  • Patent number: 5772553
    Abstract: A control system for an automatic transmission includes a clutch adapted to be applied when a forward running range is selected, for transmitting the rotation of an engine to a speed change unit. A hydraulic servo applies the clutch responsive to feed of an oil pressure and a control unit controls the oil pressure fed to the hydraulic servo. The control unit brings the clutch into a substantially released state by lowering the oil pressure of the hydraulic servo if the stop state of a vehicle is detected by a stop state detector and applies the clutch if the stop state of the vehicle is not detected with the clutch released. The oil pressure fed to the hydraulic servo is raised according to a second mode when the accelerator pedal is depressed, in preference to a first mode in which a brake pedal is released, if the accelerator pedal is depressed when the stop state of the vehicle is not detected because the accelerator pedal is released so that the engagement of the clutch has not started.
    Type: Grant
    Filed: August 30, 1996
    Date of Patent: June 30, 1998
    Assignee: Aisin AW Co., Ltd.
    Inventors: Kazumasa Tsukamoto, Masahiro Hayabuchi, Yoshihisa Yamamoto, Hiroshi Tsutsui, Yuuki Kousaka
  • Patent number: 5769753
    Abstract: A control system for an automatic transmission which includes a fluid transmission unit. The control system includes a clutch applied in a forward running range; a hydraulic servo for applying the clutch responsive to an oil pressure; input and output R.P.M. sensors for detecting the input and output R.P.M.s of the fluid transmission unit; a stop state detector for detecting that the vehicle is stopped; a start detector for detecting start of the vehicle from a stop; and a control unit for controlling the oil pressure fed to the hydraulic servo. The oil pressure of the hydraulic servo is reduced, when the vehicle is stopped, to establish a neutral control state in which the clutch is released. A completely applied state of the clutch is established by boosting the oil pressure fed to the hydraulic servo when the shift of the vehicle from a stop to start is detected, in two stages.
    Type: Grant
    Filed: October 31, 1995
    Date of Patent: June 23, 1998
    Assignee: Aisin AW Co., Ltd.
    Inventors: Muneo Kusafuka, Kazuhiro Mikami, Yoshihisa Yamamoto, Hiroshi Tsutsui, Akihito Iwata
  • Patent number: 5767198
    Abstract: To provide a thermoplastic resin composition which comprises a fluorine-containing polymer having a molecular weight of 5.times.10.sup.2 to 5.times.10.sup.5 and 2.times.10.sup.2 to 1.times.10.sup.5 methylol groups per 1.times.10.sup.6 carbon atoms at its molecular chain ends and a liquid crystal polyester or in addition a perfluoro type resin having less than 2.times.10.sup.2 methylol groups mentioned above, and has improved shrinkage from mold dimensions and dimensional stability represented by a coefficient of linear expansion with maintaining excellent characteristics of the fluorine-containing resin, such as thermal resistance, chemical resistance, weather resistance, surface properties (non-stickiness, excellent friction property), antisoil property and dielectric property.
    Type: Grant
    Filed: December 20, 1995
    Date of Patent: June 16, 1998
    Assignee: Daikin Industries, Ltd.
    Inventors: Tetsuo Shimizu, Takayuki Araki, Takafumi Yamato, Yoshihisa Yamamoto
  • Patent number: 5749802
    Abstract: An automatic transmission control apparatus has first and second hydraulic servos for engaging forward and reverse driving friction engaging elements, respectively, a fluid pressure control unit, a range shift detector, and an electronic control unit. When the forward driving range is selected, the fluid pressure control unit supplies a forward driving range pressure to the hydraulic servo via a changeover valve operated by a signal pressure from a normal open-type solenoid valve, when the signal pressure is drained. When the reverse driving range is selected, the electronic control unit outputs a signal to magnetize the solenoid valve. The solenoid valve is thus turned on to discontinue the drain. The control apparatus thus prevents low pressure in the reverse driving range pressure to prevent delay of engagement of the clutch.
    Type: Grant
    Filed: May 8, 1996
    Date of Patent: May 12, 1998
    Assignee: Aisin AW Co., Ltd.
    Inventors: Katsuyuki Tanahashi, Hiroshi Tsutsui, Yoshihisa Yamamoto, Kazumasa Tsukamoto