摘要 |
A throttle valve for throttling the flow of combustion air to an internal combustion engine is disclosed having a throttle body made of a first plastic and defining a throat for passing combustion air and an intersecting passageway to rotatably support a throttle shaft. The throttle shaft is made of a second plastic that is filled with a solid lubricant and extends through the intersecting passageway supported on each end by a boss that is molded concurrently with the throat. The inside surfaces of the bosses support the throttle shaft and are molded in the same molding process that forms the throat. A butterfly is mounted to the shaft for rotation in the conduit to throttle the flow of combustion air. Boss to throat volumetric ratios of 0.5 or less are provided by this construction. <IMAGE> |