Disc valve

A disc valve comprising in combination:

• a housing including a seal ring which is concentric relative to an axis through the valve, the seal ring including a generally radially inwardly facing, convexly curved sealing surface defining a sealing plane that is perpendicular to the valve axis, the tangent to the sealing surface at the sealing plane being a conical surface which is coaxial with respect to the valve axis;
• a valve disc defined by spaced apart end faces and a conically shaped seating surface interconnecting the end faces, a portion of the seating surface intermediate the end faces having the same dimensions as the conical surface, the disc faces being substantially parallel and slanted relative to the axis of the conical seating surface by a slant angle of not substantially more than about 10.degree.;
• and actuating means for moving the disc between an open position in which it is generally parallel to the valve axis and a closed position in which the seating surface contacts the sealing surface in the sealing plane the actuating means including means defining a pivot axis for the disc which is perpendicular to the valve axis and which is offset with respect thereto, the pivot axis extending perpendicular to the plane in which the slant angle lies and being positioned so that the slant angle trails closing motion of the disc;
• whereby additional seat ring width is provided to enable the movement of the disc beyond the closed position to increase the contact pressure between the seating and the sealing surfaces while preventing contact between them before the disc is in the closed position.

A seal ring for use with disc valves having a valve housing including means for positioning the seal ring within the housing, a valve disc including a seating surface for sealingly engaging a sealing surface of the ring, and means for pivotally moving the disc between an open position and a closed position in which the disc is substantially perpendicular to the valve axis and in engagement with the seal ring, the seal ring comprising:

• an annular base having a width in a radial direction and a thickness in an axial direction;
• a sealing member spaced radially inward of the base and defining a generally radially inwardly facing sealing surface having, in cross-section, a convexly arcuate profile of a radius "R" for engaging the seating surface of the disc;
• web means constructed of a resilient material and interconnecting the base with the member, the web means extending generally radially inward of the base and having a thickness in the direction of the valve axis which is substantially less than the thickness of the base;
• and means for causing the deformation of the member and the web means relative to the base along a generally circular path of a radius "r" when an axially acting force is applied to at least one of the members and the web means;
• and wherein "R" is greater than "r" and the circular path is arranged so that the force with which the sealing surface is biased against the seating surface is enhanced when the axially acting force is applied.

A disc valve comprising in combination:

• a valve housing;
• a seal ring which is concentric relative to an axis through the valve, the seal ring including, in cross-section, a base having a width in a radial direction and a thickness in an axial direction;
• a slanted web protruding in a generally radially inward direction from the base and having substantially parallel, generally axially oriented faces defining therebetween a slanted web center line which intersects a radially inwardly oriented surface of the base at a first point, the web further having a thickness which is substantially less than the thickness of the base so as to render it relatively flexible, and a sealing member protruding in a generally radially inward direction from an end of the web remote from the base, the sealing member terminating in a convex, arcuately shaped sealing surface extending in a generally axial direction and having a center of curvature which lies on the slanted web center line, the distance from the sealing surface to the first point being less than the distance from the sealing surface to the center of curvature, the web center line being further substantially perpendicular to a tangent to the sealing surface at the intersection between the sealing surface and the center line, the tangent defining over the full extent of the seal ring a tangent cone which is coaxial with the valve axis and which has a cone angle in the range of between about 20.degree. to about 70.degree. the intersection between the web center line and the sealing surface over the full extent of the seal ring defining a sealing plane for the valve which is perpendicular to the valve axis;
• a valve disc having spaced apart end faces and a conically shaped seating surface interconnecting the end faces and arranged for engaging the sealing surface of the seal ring at least in the sealing plane when the disc is in its closed position, conically shaped seating surface being co-axial with the valve axis when the disc is in its closed position and further having the same cone angle as the tangent cone;
• and means for pivotally moving the disc about a pivot axis between a closed position in which the seating surface engages the sealing surface along the intersection between the sealing surface and the sealing plane and an open position in which the disc is generally parallel to the valve axis, the pivot axis being perpendicular to the valve axis and being offset with respect thereto by no more than about 10 mm;
• the end faces of the disc being slanted relative to the axis of the conically shaped seating surface by an angle of no more than about 5.degree., the angle lying in a plane that is perpendicular to the pivot axis and includes the valve axis and being further arranged so that it trails the closing motion of the disc, the spacing between the end faces being sufficiently large so as to permit pivotal movement of the disc beyond the closed position, such pivotal movement resulting in a slight misalignment of the axis of the conically shaped seating surface from the axis of the tangent cone to thereby induce a slight, circumferential, resilient compression of the sealing surface of the seal ring and to thereby enhance the contact pressure between the seal ring and the disc.

In a disc valve of the type having a housing including a valve conduit defining a main axis through the valve, a seal ring carried by the housing and having a sealing surface, a valve disc defined by opposing, spaced apart end faces and a seating surface interconnecting the end faces and arranged for sealingly engaging the sealing surface of the seal ring when the disc is in its closed position, and means for pivotally moving the disc about a pivot axis which is offset from and perpendicular to the main valve between a closed position in which the seating surface engages the sealing surface and an open position in which the disc is generally parallel to the main valve axis, the improvement to the sealing surface and the disc comprising in combination:

• a sealing surface at least a portion of which defines a conical surface which is coaxial with respect to the main valve axis;
• the seating surface of the disc having a conical shape which includes the conical shape of said portion of the sealing surface and which is arranged so as to be coaxial with the main valve axis when the disc is in the closed position in which the sealing surface and the seating surface are in mutual contact in a plane perpendicular to the main valve axis;
• the disc further having a spacing between its faces which is sufficiently large so as to permit pivotal movement of the disc beyond the closed position so as to slightly misalign the axis of the seating surface from the valve axis, the disc faces being generally parallel and slanted relative to the axis of the conically shaped seating surface by an angle which lies in a plane that is perpendicular to the pivot axis and includes the main valve axis, the angle being arranged so that it trails the closing motion of the disc, whereby a premature contact is prevented between the disc and the ring as the disc moves from its open to its closed position.

A seal ring for use with disc valves having a valve housing defining a main axis through the valve and including means for positioning the seal ring within the housing, a valve disc including a seating surface for sealingly engaging a sealing surface of the seal ring, and means for pivotally moving the disc between an open position and a closed position in which the disc is substantially perpendicular to the main valve axis and in engagement with the seal ring, the seal ring comprising:

• an annular base having a width in a radial direction and a thickness in an axial direction;
• a sealing member spaced radially inward of the base and defining a generally radially inwardly facing sealing surface for engaging the seating surface of the disc, the profile of the sealing surface having a convexly arcuate configuration;
• web means constructed of a resilient material and interconnecting the base with the member, the web means extending generally radially inward of the base and having a thickness in the direction of the main valve axis which is substantially less than the thickness of the base;
• the seal ring including means adapted to cause movement of the member and the web means along a generally circular path under an axially acting force, the circular path and the arcuately shaped seal ring surface having centers which lie on a straight line that intersects a theoretical contact point between the sealing surface and the seating surface;
• whereby the formation of a seal between the sealing surface and the seating surface can be enhanced by resiliently deflecting the member and the web means through the application of increased pressure between the sealing surface and the seating surface.