Exhaust flow control valve for manifold plate

A throttle valve assembly for controlling flow of fluid through a passage, comprising:

• a housing having a straight flow passage extending therethrough, said housing also having a bore formed therein in intersecting relationship to said passage;
• valve means movably positioned within said bore for adjustably restricting the flow of fluid through said passage, said valve means including an elastomeric sleeve coaxially aligned with and positioned within said bore and being movable axially therealong between an open position wherein the sleeve projects no more than only partially into said passage and a closed position wherein said sleeve extends completely across said passage for sealingly closing off the latter, said valve means including an actuating member which is axially movably positioned within said bore and intersectingly extends across said passage when said valve means is in both said open and said closed position, said actuating member having said elastomeric sleeve mounted thereon in encircling relationship thereto;
• relatively movable abutment means coacting with said elastomeric sleeve when the latter is in or closely adjacent said closed position for axially compressing and resiliently radially deforming said sleeve into at least partial sealing engagement with said housing for restricting or preventing flow of fluid through said passage, said abutment means including a first annular abutment disposed on one side of said passage and fixed to said actuating member directly adjacent one axial end of said elastomeric sleeve for engaging the latter, said abutment means including a second annular abutment fixedly mounted relative to said housing adjacent the other side of said passage and disposed for direct engagement with the other axial end of said elastomeric sleeve when said valve means is in or closely adjacent said closed position, whereby movement of said actuating member axially of said bore from said open position toward said closed position causes said first and second abutments to relatively move toward one another and engage the opposite ends of said elastomeric sleeve when said valve means approaches said closed position for effecting axial compression of said sleeve accompanied by radial expansion thereof into sealing engagement with said housing in surrounding relationship to said passage;
• said bore being of a stepped configuration and including a first cylindrical opening of a first diameter extending inwardly of said housing through an axial extent whereby said first cylindrical opening is perpendicular to and intersects said passage, said first opening terminating at its inner end in an annular shoulder formed on said housing, which said annular shoulder defines said second abutment, said annular shoulder being disposed in close proximity to the periphery of said passage adjacent the side thereof which is remote from the open end of said bore, whereby said annular shoulder is engageable with the axial end of the elastomeric sleeve when said valve means closely approaches said closed position;
• said stepped bore including a second cylindrical opening of a second diameter which is substantially smaller than said first diameter, said second opening being coaxially aligned with said first opening and extending inwardly from said shoulder, said second opening being internally threaded;
• said actuating member including a first cylindrical portion on the outer axial end thereof which is movably positioned within said first opening, said first cylindrical portion having said elastomeric sleeve mounted therearound so that said sleeve substantially totally occupies but is slidable along said first opening, said actuating member having a radially enlarged annular flange formed thereon adjacent the outer end of said first cylindrical portion for defining thereon said first abutment;
• and
• said actuating member including a second cylindrical portion which is coaxially fixed to said first cylindrical portion and projects inwardly therefrom into said second opening, said second cylindrical portion being externally threaded and disposed in threaded engagement with said second opening.