Throttle valve unit with integrated throttle valve

The flap unit is injection molded in a single operation which forms an outer frame(3;3.1,3.2) surrounding a flap surface(4;4.1,4.2) on both sides of a shaft(2) with bearings(5,7) at each end. The frame is mounted in a two part housing onto which a housing is molded for the flap control member. Preferred Features: The flap unit is molded in two high quality polymer components in a single operation. Housing halves for mounting the flap unit are molded of a more economic material. The frame structure at the periphery of the flap surface may be molded with a constant or variable thickness. There are no undercuts on the flap molding.