Fluid handling – Self-proportioning or correlating systems – Self-controlled branched flow systems
Reexamination Certificate
2001-09-20
2004-09-21
Krishnamurthy, Ramesh (Department: 3753)
Fluid handling
Self-proportioning or correlating systems
Self-controlled branched flow systems
C137S100000, C137S625690, C251S297000
Reexamination Certificate
active
06792965
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention relates generally to poppet valves, and more particularly to improvements in the construction and operation of such valves, in which a shuttle type poppet shifts between alternate positions.
The shuttle or poppet of such a valve is required to shift position, to control fluid flow, in response to applied fluid pressure. The poppet must then be held in its alternate position in order not to inadvertently shift position during fluid flow. The use of detents to hold the shuttle in position introduces undesirable complexity to the valve, the construction of which must be simple and reliable. Accordingly, there is a need for simple, effective poppet type shuttle valves of improved construction, avoiding the use of shuttle holding detents.
SUMMARY OF THE INVENTION
It is a major object of the invention to provide an improved poppet type shuttle valve meeting the above need.
Basically, the improved shuttle valve assembly of the present invention comprises:
a) a valve housing containing first, second and third ports, and a cavity in the housing,
b) a poppet shiftable in the cavity between a first position and a second position,
c) the poppet in its first position directing flow between the first port and the second port, communication between the second port and third port then being blocked,
d) the poppet in its second position directing flow between the third port and the second port, communication between the second port and first port then being blocked,
e) and a friction responsive holder acting to hold the poppet in its first position until fluid pressure shifts the poppet to second position, and to hold the poppet in its second position until fluid pressure shifts the poppet to the first position.
As will appear, the holder may typically be carried by the poppet in a position to frictionally engage a surface to resist poppet shifting, until fluid pressure creates force that overcomes the frictional engagement of the holder and surface.
It is another object of the invention to provide the holder in the form of an elastomeric O-ring that extends about an axis defined by the poppet, that axis extending in the direction of poppet shifting.
It is a further object of the invention to locate the O-ring out of the direct flow paths of pressurized fluid in each of the first and second poppet positions.
Yet another object is to provide a body having a bore into which the housing is endwise received, the body having first, second and third passages in registration with the first, second and third ports, respectfully. As will be seen, such passages may typically intersect the body bore, sidewardly of the poppet.
A further object is to provide spaced piston surfaces on the poppet for receiving fluid pressure acting to shift the poppet between said positions, the O-ring located between said piston surfaces.
A yet further object is to provide the second port to have two sections which are longitudinally spaced apart and which intersect a bore defined by the housing at intersection locations, said friction responsive holder remaining between said intersection locations at all times during shifting of the poppet between its first and second positions, and the second port having an additional section which is longitudinally elongated, radially outwardly of the holder, and which intersects radially outward extents of said two sections of the second port.
An additional and important object is to provide a simple, rugged, reliable shuttle valve assembly that comprises fewer than 10 parts, as for example is shown in the drawings.
These and other objects and advantages of the invention, as well as the details of an illustrative embodiment, will be more fully understood from the following specification and drawings, in which:
REFERENCES:
patent: 1469854 (1923-10-01), Stuart
patent: 1919430 (1933-07-01), Hewitt
patent: 2354791 (1944-08-01), Boldt
patent: 2358228 (1944-09-01), Hoof
patent: 2366608 (1945-01-01), Freeman
patent: 2440478 (1948-04-01), Kehle
patent: 2729226 (1956-01-01), Jones
patent: 3043325 (1962-07-01), Slawson
patent: 3155105 (1964-11-01), Yanna
patent: 3533431 (1970-10-01), Kuenzel et al.
patent: 3642020 (1972-02-01), Payne
patent: 3687153 (1972-08-01), Gold
patent: 4187871 (1980-02-01), Hendrickson
patent: 4281677 (1981-08-01), Hoffman
patent: 5127426 (1992-07-01), D'Archambaud
patent: 6196252 (2001-03-01), Martin et al.
patent: 6296008 (2001-10-01), Boyer et al.
Krishnamurthy Ramesh
Smiths Aerospace Actuation Systems-Yakima, Inc.
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