A wastegate is provided in an exhaust bypass passage that allows exhaust gas to bypass a turbine wheel of an exhaust turbine-type forced-induction device. A required boost pressure is set in accordance with a running state of an engine. A controller is configured to control a drive force of the wastegate to a magnitude that achieves the required boost pressure when the required boost pressure is higher than a preset pressure, and control the drive force to a magnitude that achieves a higher boost pressure than the required boost pressure when the required boost pressure is less than or equal to the preset pressure.

A wastegate assembly for controlling flow of exhaust gas includes a valve element having a valve body and a valve shaft. The wastegate assembly further includes a spindle. The wastegate assembly further includes a washer coupled to the valve shaft and spaced from the spindle for securing the spindle to the valve shaft. A plurality of cup springs is disposed between the spindle and the washer. The plurality of cup springs includes at least a first cup spring and a second cup spring, with the first cup spring supported on the spindle head and the second cup spring orientated substantially identical to the first cup spring and disposed directly on the first cup spring.

An actuator 1 includes a housing 2, an output shaft 3 projecting from the inside of the housing 2 to the outside, a motor 4 provided in the housing 2, a reduction mechanism 5 which connects the motor 4 to the output shaft 3, a magnet 61 provided for rotation integrally with the output shaft 3 inside the housing 2, a Hall effect IC 62 disposed to face the magnet 61 outside the rotation locus of the magnet 61, and a circumferential wall 25 disposed to stand from the inner wall of the housing 2 and interposed between the magnet 61 and the Hall effect IC 62.

A wastegate is attached to a turbine housing of a turbocharger. The wastegate opens and closes a bypass passage. An actuator is coupled to the wastegate via a link mechanism. The link mechanism includes a link rod and a link arm. The longitudinal direction of the link rod in a state in which the bypass passage is fully closed is defined as a width direction of the link arm. The coupling center position in the link arm to which the link rod is coupled is located at a position offset in a direction in which the link rod moves to open the wastegate from a middle of the link arm in the width direction.

The invention relates to a valve assembly (100) for a multi-scroll turbine (10) for controlling an overflow of exhaust gases between a first spiral (36) and a second spiral (38) and for controlling a bypass opening (50). The valve assembly 100 comprises a lever (110) and a valve closing element (120) which is operatively connected to the lever (110). Furthermore, the valve assembly (100) comprises a spring element (130) which is designed to pre-bias the valve closing element (120) the against lever (110).

A variable flow rate valve mechanism includes a valve, a lock member, a valve attachment member and a spring washer. The valve includes a valve body and a valve shaft. The lock member is fixed to the valve shaft. The valve attachment member is attached to the valve shaft. The spring washer is disposed adjacent the valve attachment member. The spring washer is formed into an annular shape around an axis of the spring washer. The spring washer includes a support portion, a deformable portion and a protrusion portion. The support portion includes a seat surface and an open surface. The deformable portion is connected to the support portion and extends in an inclined manner. The deformable portion includes a contact surface and an opposite surface. The protrusion portion protrudes from at least one of the open surface of the support portion and the opposite surface of the deformable portion.

A method and system for controlling operation of a two-stroke engine having a turbocharger includes the two-stroke engine comprising an electronically controlled exhaust valve. A throttle position sensor generates a throttle position signal corresponding to a position of a throttle plate of a throttle. A boost box is coupled to the two-stroke engine. A boost box pressure sensor is coupled to the boost box and generates a boost box pressure signal corresponding to a pressure within the boost box. A controller is coupled to the boost box pressure signal controlling a position of the electronically controlled exhaust valve in response to the boost box pressure signal and the throttle position signal.

A turbocharger includes a turbine housing accommodating a turbine wheel, and a waste gate valve connected to the turbine housing. A valve seat for the waste gate valve is provided at an opening edge of a bypass passage on an inner wall surface of the turbine housing. The waste gate valve includes a shaft rotatably supported by a wall, and a valve element extending in a radial direction of the shaft from an end portion of the shaft on an inner side of the turbine housing. A contact surface of the valve seat and a contact surface of the valve element are a flat surface. The waste gate valve is a one-piece molding including the shaft and the valve element.

A charging device may include a turbine housing and a wastegate valve device. The wastegate valve device may include a flap, a spindle arm, a wastegate spindle, an axial stop, and a lever arm non-rotatably attached to the wastegate spindle. The wastegate spindle may be rotatably mounted in a bushing disposed on the turbine housing. A wastegate duct may be disposed in the turbine housing. The wastegate duct may have a duct aperture enclosed by a valve seat. The duct aperture, when in a closed state, may be closed by the flap of the wastegate valve device. A sealing face of the flap may be defined by a sequence of at least two conical peripheral surfaces arranged next to one another and each having a different inclination.

A turbocharger manifold is disclosed. In one embodiment, the manifold has a first exhaust conduit, a second exhaust conduit, and a valve. The first exhaust conduit has a first exhaust inlet and a first turbocharger outlet. The second exhaust conduit has a second exhaust inlet and a second turbocharger outlet. The second exhaust inlet is connected to the first exhaust conduit. The valve has an open position and a closed position and controls exhaust gas access from the first exhaust conduit to the second exhaust conduit.