| 摘要 |
<p>In the representative embodiment of the invention disclosed herein, a disc valve is cooperatively arranged to include a disc member of a ductile material which is transversely positioned within an enlarged chamber in the axial bore of a tubular housing and sealingly secured to the housing. A piston-actuated tubular mandrel having a forward position defining a slanted annular cutting edge with a notch on one side thereof is arranged in the housing so that as the mandrel is advanced against the disc, the inclined cutting edge will progressively sever the central portion of the disc from its peripheral portion and progressively bend that part of the central disc portion disposed in the notch outwardly to confine the central disc portion between the housing wall and the exterior of the mandrel.</p> |
