A rotary valve including a housing having an inner surface. A rotary
assembly is positioned for rotation within the housing. The rotary
assembly includes a plurality of radially outwardly extending vanes. The
vanes extend toward the inner housing surface and are configured to
transport material along the inner housing surface. Seal members are
mounted upon the vanes. Spring members are secured to the vanes urging
the seal members into contact with the inner housing surface.