초록 ▼

A center flow check valve of the diaphragm type is inexpensive to manufacture and has reliably great sensitivity in both forward and reverse flow. The valve includes an imperforate diaphragm that is loose, e.g., is not affirmatively held in place by a pin or the like, and the center portion of the d

A center flow check valve of the diaphragm type is inexpensive to manufacture and has reliably great sensitivity in both forward and reverse flow. The valve includes an imperforate diaphragm that is loose, e.g., is not affirmatively held in place by a pin or the like, and the center portion of the diaphragm as well as the periphery move axially in various modes of operation. Various elements help to keep the diaphragm centered. A reverse flow path directs back flow to the center of the downstream surface of the diaphragm. The back flow lifts the diaphragm from support edges about which it flexes during forward flow and seals it against a concave sealing surface. The diaphragm is protected against strong pressure in the forward direction by a flow deflector and against strong back flow pressure by the concave sealing surface. In the absence of forward or backward fluid pressure, the diaphragm assumes a neutral configuration in which it seals against back flow by making line contact with a convex curved surface disposed on the upstream side of the diaphragm.

대표청구항 ▼

A check valve for passing fluid flow in a forward direction from an upstream side of the valve to a downstream side, and for preventing fluid flow in a reverse direction, comprising: a valve body defining a substantially axisymmetric chamber, with internal surfaces of the valve body defining a bound

A check valve for passing fluid flow in a forward direction from an upstream side of the valve to a downstream side, and for preventing fluid flow in a reverse direction, comprising: a valve body defining a substantially axisymmetric chamber, with internal surfaces of the valve body defining a boundary of the chamber; an imperforate flexible diaphragm disposed concentrically in the chamber; the valve body having an inlet passage formed therein in fluid communication with the chamber and extending in the upstream direction from the chamber, the diaphragm being responsive to reverse flow into the chamber for blocking the fluid communication between the chamber and the inlet passage; the valve body having an outlet passage formed therein extending from the chamber in the downstream direction; and substantially axisymmetric diaphragm contacting means for contacting and supporting a downstream face of the diaphragm during forward flow, said axisymmetric means being spaced radially from the boundary of the chamber and from the periphery of the diaphragm, the axisymmetric means supporting the diaphragm such that the portion of the diaphragm that is disposed radially outwardly of the axisymmetric means may flex in a downstream direction about the axisymmetric means during forward flow to allow for the passage of fluid, the axisymmetric means defining a reverse flow passage for guiding fluid to the center of the downstream face of the diaphragm during reverse flow, the axisymmetric means comprising at least one sharp edge effective to press into the diaphragm and inhibit lateral motion of the diaphragm, the at least one sharp edge being formed on a member disposed in the chamber, the member having a radially inner surface extending in a substantially longitudinal direction along said reverse flow passage to a place where it terminates in said sharp edge, the member further having a radially outer surface tapering inwardly in the upstream direction to a place where it meets said radially inner surface in said sharp edge.