Centric butterfly valve
AssigneeKitz Corporation
InventorTakeshi GOMI
Life of this patent
Estimating the term…
Abstract
[Problem] To provide a centric butterfly valve which has favorable sealability around stems and small open/close operation torque and is also excellent in durability. [Solution] A centric butterfly valve (1) in which top and bottom boss surfaces (19, 29) are formed to be spherical, an outer peripheral end of the blade portion of the valve disk (24) is formed to be an M-shaped section part (29) with round-shaped apex parts (27) and a round-shaped valley part (28) smoothly linked, and the centric butterfly valve has a valve disk (3) having an extended part (41) obtained by successively and slightly extending the spherical surface of each of the top and bottom boss surfaces (19, 20) to a blade portion (40) side.
Claims10
1-9. (canceled)
A centric butterfly valve in which a valve disk having top and bottom boss surfaces provided upper and lower parts and an outer peripheral seal part provided at an outer peripheral end of a blade portion of the valve disk is rotatably provided inside a cylindrical-type body via stems, the outer peripheral seal part is an M-shaped section part with two linear round-shaped apex parts positioned on a primary side and a secondary side and a round-shaped valley-bottom part positioned between the apex parts smoothly linked, this M-shaped section part has the two linear apex parts crushed in a fully-closed state and other portions moved to a direction of a space of the valley-bottom part to form two linear seal parts by the apex parts, an inner peripheral surface of the body has a seal surface formed of an arc surface and, when the outer peripheral end of the blade portion of the valve disk makes contact with the arc surface of the body, the valley-bottom part of the M-shaped section part becomes in a state of being substantially in contact with the arc surface.
Dependencies are inferred from the claim text.