Sealing structure for rotary valves

Claim 1

A sealing structure for a rotary valve, comprising: a rotary member provided with a plurality of pockets opening toward the outer periphery of said rotary member; a casing enclosing the outer periphery of said rotary member; sealing members provided between the outer periphery of said rotary member and the inner periphery of said casing; said sealing members being formed to be adjustably projectable in the radial direction; radial blades partitioning and separating said plurality of pockets provided in said rotary member; cavities in the outer tips of said blades; said sealing members being slidably fitted in said cavities to be pressed to project outwardly in the radial direction of said rotary member; a supporting shaft for said rotary member; a rod member disposed in one end of said supporting shaft; a hole formed in the axial direction at the center of said rotary member; an adjusting member slidably fitted in said hole and advanced and retreated in the axial direction by said rod member advanced and retreated as operated from outside at said one end of said supporting shaft of said rotary member; said cavities being connected with said hole through passages provided radially within said blades; and pushing members slidably fitted in said passages to be in contact at one end thereof with the back surface side of said sealing member and at the other end thereof with said adjusting member so that the sealing members may be projected by said pushing members through the sliding of said adjusting member.