Gasket with curved configuration at peripheral edge

Abstract

A gasket having the form of a frame is provided with a curved portion at an inner or outer periphery thereof. When used in combination with a similarly configured gasket, the two gaskets may together, upon compression, form a pinch seal. The curved portion may be provided with a chemically resistant material.

What is claimed is:  
     
         1 . A gasket in the form of a frame having an inner peripheral edge and an outer peripheral edge, the inner peripheral edge of the gasket being of continuously curved convex configuration and being provided with a liner of chemically resistant material conforming with the continuously curved inner peripheral edge.  
     
     
         2 . A gasket as claimed in  claim 1 , in which the liner is made of polytetrafluoroethylene.  
     
     
         3 . A gasket as claimed in  claim 1 , in which the inner peripheral edge is part-circular in cross-section.  
     
     
         4 . A gasket as claimed in  claim 1  provided with holes to accommodate sealing bolts.  
     
     
         5 . A gasket as claimed in  claim 1  in which the frame is of square or rectangular configuration.  
     
     
         6 . A gasket as claimed in  claim 1  in which the cross-section of the frame is of rectangular cross section with the dimension perpendicular to the gasket plane being smaller than the dimension in the plane of the gasket.  
     
     
         7 . A gasket as claimed in  claim 1  in which the opposite faces of the gasket are planar.  
     
     
         8 . A gasket in the form of a frame having an inner peripheral edge and an outer peripheral edge and including a protrusion or nose at its inner and/or outer peripheral edge.  
     
     
         9 . A gasket as claimed in  claim 8 , in which the protrusion or nose extends around substantially the entire perimetral length of the frame.  
     
     
         10 . A gasket as claimed in  claim 8 , which the protrusion or nose is provided on the inner peripheral edge of the gasket frame.  
     
     
         11 . A gasket as claimed in  claim 10 , in which the protrusion or nose is of curved configuration.  
     
     
         12 . A gasket as claimed in  claim 10 , in which the protrusion or nose is of curved bulbous configuration.  
     
     
         13 . A gasket as claimed in  claim 10 , further including a liner of chemically resistant material provided on said inner peripheral edge and conforming to the configuration of the nose.  
     
     
         14 . A gasket as claimed in  claim 13 , in which the liner is made of polytetrafluoroethylene.  
     
     
         15 . A gasket as claimed in  claim 8  in which the protrusion or nose is of a shape capable of effecting a pinch seal when used with a second gasket in the form of a frame having an inner peripheral edge and an outer peripheral edge, the inner peripheral edge of the gasket being of continuously curved convex configuration and being provided with a liner of chemically resistant material conforming with the continuously curved inner peripheral edge.  
     
     
         16 . A gasket as claimed in  claim 8  in which the gasket is provided with a protrusion or nose on opposite sides thereof.  
     
     
         17 . A gasket as claimed in  claim 8  in which the frame is locally enlarged at its inner peripheral edge to form said nose which projects beyond the plane of the gasket on one side thereof to effect sealing contact.  
     
     
         18 . A gasket as claimed in  claim 8  comprising a frame for compression together with the frame of a second gasket of similar configuration between a pair of flanges, the protrusion being resilient for effecting a pinch seal with a similar protrusion on a second gasket.  
     
     
         19 . A gasket effective for compression together with the frame of a second gasket of similar configuration between a pair of flanges, the gasket comprising a frame having a resilient protrusion on one side thereof for effecting a pinch seal with a similar protrusion on a second gasket, the resilient protrusion being located at or adjacent the inner periphery of the frame and remote from the outer periphery of the frame, and in which the inner periphery of the gasket is protected by a chemically resistant liner which extends over the protrusion.  
     
     
         20 . A gasket as claimed in  claim 20 , wherein the chemically resistent liner comprises polytetrafluoroethylene.