Exhaust turbine equipped with exhaust control valve
Provided is an exhaust turbine equipped with an exhaust control valve which can reduce wear of the contact surfaces between the shaft and the bushing or the turbine casing. The exhaust turbine is equipped with the exhaust control valve for opening/closing an exhaust bypass passage leading the exhaust turbine being driven by exhaust gas output from an engine to an exhaust outlet passage while bypassing the exhaust turbine, wherein the exhaust control valve comprises a shaft which is supported rotation-freely by a turbine casing and supports a valve element, an arm equipped with a connecting part with a drive source and turning the shaft about the axis thereof by the reciprocating motion of the connecting part produced by the drive source, and a weight attached to an end on the side opposite to the connecting part with the drive source with respect to the axis of the shaft.
1. An exhaust gas turbine driven by exhaust gas emitted from an engine and being equipped with an exhaust gas control valve for closing and opening an exhaust gas bypass passage through which the exhaust gas emitted from the engine bypasses the exhaust gas turbine and flows into an exhaust waste gas outlet passage, the exhaust gas control valve comprising:
a support axis shaft for supporting a valve body which controls an opening of the exhaust gas bypass passage, the support axis shaft being rotation-freely or swing-freely supported in a turbine casing of the exhaust gas turbine;
an arm which is provided with a connecting part at an end part thereof for connecting the support axis shaft to an actuator, and rotates or swings the support axis shaft around an axis of the support axis shaft by reciprocating rotational movements or swing movements that are transferred from the actuator; and
a weight equipped at an end part opposite to where the connecting part is provided, with respect to the axis of the support axis shaft,
wherein a center of the valve body of the exhaust gas control valve is located at a predetermined distance apart from the connecting part via which running gears or moving parts of the exhaust gas control valve are operated, in the direction of the axis of the support axis shaft; and, the center of gravity of the weight in the direction of the axis is placed at a position between the connecting part and the valve body center.
2. The exhaust gas turbine equipped with an exhaust gas control valve according to claim 1 , wherein the arm and the weight are formed as a single piece made by casting or forging, and a middle part of the arm is fixed to the support axis shaft.
3. The exhaust gas turbine equipped with an exhaust gas control valve according to claim 1 , wherein a middle part of the arm is fixed to the support axis shaft, the weight is equipped at the end part of the arm opposite to another end part of the other arm, at which the connecting part is provided and transfers the operation movements from the actuator to the moving parts of the waste gate valve, further wherein, the weight is fastened to the arm by means of at least one self-locking nut and a bolt.