Abstract: A wastegate valve for use with turbocharged engines. The wastegate valve vents exhaust gasses upstream of the turbocharger high pressure turbine to reduce turbocharger speed and associated boost pressure. The wastegate valve includes a piston attached to a poppet valve and movable within a housing. The housing receives pressurized intake gasses at a side of the piston to actuate the popper valve between open and closed positions. A diaphragm is sealingly disposed between the piston and housing. The housing includes mechanical stop means to limit the piston travel, thereby reducing flexure of the diaphragm. Additionally, the diaphragm is disposed in the housing in such a way that the diaphragm flexes between reduced peak compressive and tensile stresses.

Abstract: A coupling assembly is disclosed for connecting a tube to a housing member. Preferably, the coupling assembly includes a tube end having a pair of spaced apart annular beads defining a groove for receiving a resilient seal ring seated therein and a housing member defining a bore for receiving the tube end. Also, a guide ring preferably centers the tube end in the bore. A clamping assembly is provided according to the present invention which includes symmetric clamping members, each defining a tube engaging portion between a seat portion and a seat engaging portion. The clamping members assemble axially and resiliently flex relative one another to clamp onto the tube as the seat portions axially engage the seat engaging portions.