TURBOCHARGER WASTE-GATE VALVE BUSHING

摘要

A turbocharger for an internal combustion engine includes a rotating assembly having a turbine wheel disposed inside a turbine housing and a compressor wheel disposed inside a compressor cover. The turbocharger also includes a waste-gate assembly configured to selectively redirect at least a portion of the engine's post-combustion gases away from the turbine wheel. The waste-gate assembly includes a valve, a rotatable shaft connected to the valve, and a bushing fixed relative to the turbine housing and disposed concentrically around the shaft such that the shaft rotates inside the bushing for opening and closing the valve. The bushing is defined by a length, an outer surface in contact with the turbine housing, and an inner surface in contact with the shaft. The inner surface includes a plurality of longitudinal grooves configured to counteract friction between the bushing and the shaft and avoid seizure of the shaft relative to the bushing.

主权项

1. An internal combustion engine comprising:
a cylinder configured to receive an air-fuel mixture for combustion therein; a reciprocating piston disposed inside the cylinder and configured to exhaust post-combustion gases therefrom; and a turbocharger in fluid communication with the piston and configured to pressurize an airflow being received from the ambient and deliver the pressurized airflow to the cylinder, the turbocharger including:
a turbine housing and a compressor cover;a rotating assembly having a turbine wheel disposed inside the turbine housing and a compressor wheel disposed inside the compressor cover, wherein the rotating assembly is rotated about an axis by the post-combustion gases; anda waste-gate assembly configured to selectively redirect at least a portion of the post-combustion gases away from the turbine wheel and thereby limit rotational speed of the rotating assembly and a pressure of the airflow received from the ambient, the waste-gate assembly having:
a valve, a rotatable shaft connected to the valve, and a bushing fixed relative to the turbine housing and disposed concentrically around the shaft such that the shaft rotates inside the bushing to thereby selectively open and close the valve;wherein the bushing is defined by a length, an outer surface in contact with the turbine housing, and an inner surface in contact with the shaft, and wherein the inner surface includes a plurality of longitudinal grooves configured to counteract friction between the bushing and the shaft and avoid seizure of the shaft relative to the bushing.