СИСТЕМА ВПУСКА


  1. CONSTRUCTION


    1. A variable nozzle vane type turbocharger is used.

    2. The variable nozzle vane type turbocharger consists primarily of a compressor wheel, turbine wheel, nozzle vane, unison ring, drive arm, driven arm, actuator (motor and nozzle vane position sensor) and linkage.

    3. This turbocharger has achieved great improvements in low-speed torque, maximum output, fuel consumption and emission reduction. These improvements have been accomplished through variable control of the nozzle vane position, and maintenance of an optimal velocity of the exhaust gas inflow to the turbine at all times in response to the engine condition.

    4. The ECM outputs a signal to the turbocharger sub-assembly, which operates the actuator, to control the nozzle vane position.

      A01QFSOC01
      *1 Turbocharger Sub-assembly *2 Linkage
      *3

      Actuator


      • DC Motor

      • Nozzle Vane Position Sensor

      		 *4 Compressor Wheel
      *5 Unison Ring *6 Nozzle Vane
      *7 Turbine Wheel *8 Drive Arm
      *9 Driven Arm - -

  2. OPERATION


    1. General


      1. The exhaust gas from the exhaust manifold goes through the nozzle vane inside the turbocharger housing, and flows to the exhaust pipe through the turbine. The speed of the turbine (supercharging pressure) differs depending on the flow velocity of the exhaust gas going through the turbine and the flow velocity of the exhaust gas is controlled by the opening. Where there is less exhaust gas, such as during idling, the nozzle vane is almost fully closed. However, as there is a slight clearance between the vanes, the exhaust gas flows through the clearance to the exhaust pipe, and there is no bypass.

        A01QFKBC01
        *1 Nozzle Vane - -
        A01QFNN Intake Air A01QFTC Exhaust Gas

    2. At Low Load Range or Low Speed Range


      1. The actuator moves the linkage in the closing direction of the nozzle vanes in accordance with signals from the ECM.

      2. This results in increasing the velocity of the exhaust gas flowing to the turbine, as well as the speed of the turbine. As a result, torque is improved when the engine is running at low speeds.

        A01QF4QC02
        *1 Turbocharger Sub-assembly *2 Nozzle Vane
        *3 Unison Ring *4 Turbine Wheel
        *5 Drive Arm *6 Driven Arm
        *7 Linkage - -
        *a Exhaust Gas Flow - -

    3. At High Load Range or Medium-to-high Speed Range


      1. The actuator moves the linkage in the opening direction of the nozzle vanes in accordance with signals from the ECM. This opens the nozzle vane and holds the specified supercharging pressure, lowering the back pressure and improving the output and fuel consumption.

        A01QFEFC02
        *1 Turbocharger Sub-assembly *2 Nozzle Vane
        *3 Unison Ring *4 Turbine Wheel
        *5 Drive Arm *6 Driven Arm
        *7 Linkage - -
        *a Exhaust Gas Flow - -