Patents by Inventor Sigeo Tamaki

Sigeo Tamaki 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: 4840146
    Abstract: A multiple throttle mechanism comprises a pair of intake manifold blocks separated from each other and each having two or more parallel passages formed therethrough and a wall portion separating thereby the adjacent parallel passages, the parallel passages each being a part of each of the intake manifold passages communicating with respective engine cylinders, and a pair of throttle shafts arranged in an axial direction, each crossing the parallel passages, passing through a through hole formed in the wall portion of the intake manifold block and supported on the intake manifold block, the throttle valves being mounted on the throttle shafts so that the throttle valves are operated simultaneously to control the cross sectional area of each of the parallel passage. The multiple throttle mechanism further comprises air gaps formed between an inner circumference of the through holes and an outer circumference of the shafts to provide an initial air flow.
    Type: Grant
    Filed: May 5, 1988
    Date of Patent: June 20, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Shozo Yanagisawa, Sigeo Tamaki, Isamu Ishizawa
  • Patent number: 4809659
    Abstract: This invention relates to a motor-driven throttle valve assembly which drives a motor according to the amount of depression of the accelerator pedal (9) and thereby controls the opening of the throttle valve (2). The motor-driven throttle valve assembly of this invention has a restricting plate (14), which is located between the throttle valve shaft bearing (16) on the motor side and a gear mechanism (10) transmitting the rotation of the motor to the throttle valve shaft (3), controls the rotation of the throttle valve shaft (3) toward the closed position.
    Type: Grant
    Filed: June 2, 1987
    Date of Patent: March 7, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Sigeo Tamaki, Isamu Ishizawa
  • Patent number: 4779597
    Abstract: A fail-safe system against the sticking of the throttle valve is disclosed for an automotive engine at a type with a fuel supply unit and the throttle valve driven through an actuator. The amount of depression of the accelerator pedal is detected by an accelerator pedal sensor. The system further comprises a device for detecting that the throttle valve is stuck, and a device for controlling the fuel flow rate from the fuel supply unit in accordance with an output of the accelerator pedal sensor when the throttle valve is stuck. The system preferably further comprises an auxiliary air path bypassing the throttle valve. The bypass air mount from the auxiliary air path is controlled if the throttle valve is stuck at a low opening degree, while the fuel flow rate of the fuel supply unit is controlled if the throttle valve is stuck at a middle or high opening degree.
    Type: Grant
    Filed: December 31, 1987
    Date of Patent: October 25, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Yutaka Takaku, Sigeo Tamaki
  • Patent number: 4712531
    Abstract: An apparatus for adjusting the specific volume of intake air for an engine has an orifice for controlling the amount of air to by-pass a throttle valve. The apparatus is provided with a lattice-shaped heating element which is disposed on the downsteam side of the orifice. Thus, carbon and other substances which may flow back from the engine are trapped and burnt by the heating element.
    Type: Grant
    Filed: May 8, 1985
    Date of Patent: December 15, 1987
    Assignee: Hitachi, Ltd.
    Inventors: Isamu Ishizawa, Sigeo Tamaki
  • Patent number: 4660518
    Abstract: Compensation for misoperation of the return spring which is coupled to the throttle valve of an internal combustion engine is effected by way of a mechanism which monitors the operation of the engine. Upon detection of a deceleration condition, the mechanism, which may include a mechanical spring-coupled arrangement, an electromagnetic coupling element or a solenoid, operates to engage the throttle valve and rotate the throttle valve to a prescribed opening position slightly ahead of the normal ideal return position.
    Type: Grant
    Filed: January 27, 1986
    Date of Patent: April 28, 1987
    Assignee: Hitachi, Ltd.
    Inventor: Sigeo Tamaki
  • Patent number: 4247491
    Abstract: An accelerator pump for a carburetor comprises a piston assembly inserted in a cylindrical well formed in a carburetor body, a link mechanism for actuating the piston assembly in response to movement of a throttle valve, and a tapered stopper. The piston assembly is separated from the link mechanism and engaged with it only when accelerated. The tapered stopper is inserted in a hole made in said carburetor body, which hole is perpendicular to the cylindrical well, passing through a hole made in the piston assembly. A gap defined between the tapered stopper and the periphery portion of the hole of the piston assembly determines the stroke of the piston assembly. Further, the gap is adjusted by axial movement of the tapered stopper. The tapered stopper is locked with sealing material after being adjusted so that any user can not re-adjust the tapered stopper.
    Type: Grant
    Filed: January 5, 1979
    Date of Patent: January 27, 1981
    Assignee: Hitachi, Ltd.
    Inventors: Sigeo Tamaki, Tohru Nakagawa
  • Patent number: 4245608
    Abstract: An idling control apparatus for an internal combustion engine includes a valve element amounted in a passage for air for idle running of the engine bypassing a throttle valve mounted in a suction conduit for communicating a portion of the suction conduit upstream of the throttle valve with a portion thereof downstream of the throttle valve, and a bimetal member in the form of a spiral operatively connected to the valve element for varying the quantity of air flowing through the passage for air for idle running of the engine in accordance with changes in the temperature of the engine.
    Type: Grant
    Filed: July 2, 1979
    Date of Patent: January 20, 1981
    Assignee: Hitachi, Ltd.
    Inventors: Sigeo Tamaki, Tohru Nakagawa
  • Patent number: 3937194
    Abstract: Alarm apparatus is provided for a recirculating exhaust gas flow control device, which device is employed in an internal combustion engine responsive to the negative pressure induced in the carburetor of the engine for controlling the flow of exhaust gas that is recirculated into the fuel-air mixture to be sucked into the engine; the device has a high pressure chamber in communication with the atmosphere, a low pressure chamber in communication with the engine negative intake pressure, and a diaphragm between the chambers for driving a valve that controls the flow of recirculating exhaust gas. The alarm apparatus employs a diaphragm forming high and low pressure chambers and for driving an actuating rod of a control circuit having an alarm signal lamp.
    Type: Grant
    Filed: February 25, 1974
    Date of Patent: February 10, 1976
    Assignee: Hitachi, Ltd.
    Inventors: Sigeo Tamaki, Tomoo Itoh
  • Patent number: RE34906
    Abstract: This invention relates to a motor-driven throttle valve assembly which drives a motor according to the amount of depression of the accelerator pedal (9) and thereby controls the opening of the throttle valve (2). The motor-driven throttle valve assembly of this invention has a restricting plate (14), which is located between the throttle valve shaft bearing (16) on the motor side and a gear mechanism (10) transmitting the rotation of the motor to the throttle valve shaft (3), controls the rotation of the throttle valve shaft (3) toward the closed position.
    Type: Grant
    Filed: August 14, 1992
    Date of Patent: April 18, 1995
    Assignee: Hitachi, Ltd.
    Inventors: Sigeo Tamaki, Isamu Ishizawa