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US 4,489,750 AGranted
Pressure operated pulsatile fluid flow device
AssigneeDavol Inc.
InventorJohn R. Nehring
Life of this patent
Estimating the term…
Abstract
Pulsations are created in a fluid flow stream by a pulsatile device. The device includes a flexible, resilient element which oscillates under the influence of a pressure differential to interrupt the fluid flow at regular intervals, thereby causing the outlet flow to pulsate. The device may be connected directly to a supply of fluid under pressure.
Claims6
A fluid flow control device comprising:
- a housing having an inlet, an outlet and defining a fluid flow path from the inlet to the outlet;
- a flexible, resilient valve means located within the housing along the flow path for normally obstructing the flow path to preclude flow through the outlet, said valve means comprising a hollow, cylindrical resilient and flexible member having a closed end and open end, said member having greater resistance to axial collapse than to radial collapse;
- said valve means further comprising a cylindrical holder adapted to receive the valve member, at least a portion of the open end of the valve member being disposed within the cylindrical holder with the closed end protruding out of the holder, thereby exposing a portion of the peripheral cylindrical surface of the valve member, at least part of that portion of the cylindrical member which is disposed within the holder effecting a seal between the inner cylindrical surface of the holder and the outer cylindrical surface of the open end of the valve member;
- said valve means being constructed and arranged to shift to an open position in response to a triggering pressure differential of a first magnitude across the valve means, and to return to its obstructing position in response to a drop in said pressure differential to a second magnitude which is less than that of said first magnitude;
- said valve means being constructed and arranged to define a toggle action when shifting from its obstructing to its open configuration, said toggle action being effective to substantially instantaneously shift said valve means from said obstructing to said open position;
- the length of the valve member being approximately double the length of the holder.
3 more elements
A fluid flow device for generating pulsatile flow comprising:
- a housing having an inlet, an outlet, and defining a fluid flow path from the inlet to the outlet;
- flexible, resilient valve means located within the housing along the flow path for normally obstructing the flow path to preclude flow through the outlet;
- said valve means being constructed and arranged to shift between open and obstructing positions in response to changes in the pressure differential between a higher pressure upstream of the valve means and a lower pressure downstream of the valve means;
- said valve means being further constructed and arranged to shift to an open position in response to a triggering pressure differential of a first magnitude across the valve means, and to teturn to its obstructing position solely under the influence of its resilience in response to a drop in the pressure differential across the valve means to a second magnitude which is less than said first magnitude;
- whereby said valve means will oscillate between open and obstructing positions in response to a fluid pressure at the inlet sufficient to create a pressure differential of said first magnitude, said oscillation causing pulsatile flow at the outlet;
- said valve means further comprising a hollow, cylindrical resilient and flexible member having a closed end and an open end, said member having greater resistance to axial collapse than to radial collapse;
- a cylindrical holder adapted to receive the valve member;
- at least a portion of the open end of the valve member being disposed within the cylindrical holder with the closed end protruding out of the holder, thereby exposing a portion of the peripheral cylindrical surface of the valve member;
- at least part of that portion of the cylindrical member which is disposed within the holder effecting a seal between the inner cylindrical surface of the holder and the outer cylindrical surface of the open end of the valve member;
- the cylindrical wall of the valve element including a weakened region extending longitudinallly of the element;
- the inner diameter and outer diameter of the cylindrical section of the tubular valve member being located eccentrically thereby defining a longitudinally extending narrowed wall portion for the valve member.
8 more elements
Dependencies are inferred from the claim text.