Fluid handling – Liquid level responsive or maintaining systems – By float controlled valve
Reexamination Certificate
1999-12-09
2001-12-25
Walton, George L. (Department: 3753)
Fluid handling
Liquid level responsive or maintaining systems
By float controlled valve
C137S423000, C137S428000, C137S430000, C137S436000, C137S244000
Reexamination Certificate
active
06332475
ABSTRACT:
TECHNICAL FIELD
This invention relates to a filling stop valve, particularly to the automatic cut off of flow of liquid when the liquid reaches a desired level.
BACKGROUND ART
Float valves are well known to cut off the flow of liquid when a desired level of the liquid has been reached in a container. The simplest form of such a valve comprises a float on an end of an arm pivoted to the body of the valve, the other end of the arm pressing on a valve member to close an aperture in an inlet pipe. The float arm is of a length such that the required pressure can be applied to the valve to close against the inlet liquid pressure
In order to obtain further control of the liquid flow and obtain the desired cut off of the flow, servo valves are known, in which a pilot valve controls the operation of a master valve by the application of liquid pressure to assist in the operation of the master valve. The use of a servo valve thus eliminates or reduces the length of the float arm, the servo valve incorporating a diaphragm as the master valve or connected to the master valve.
One example of a diaphragm valve given in AU 659356 in which a sensing or pilot diaphragm has attached thereto a ring magnet. A further magnet is attached to a plunger which is adapted to open and close an aperture in the diaphragm of the master valve.
Various other patent specifications, such as U.S. Pat. Nos. 3,994,313; 4,013,091; 4,977,923; 5,067,516; and 4,027,693; which show servo valves having a diaphragm valve as the master valve which is controlled by a servo valve comprising a solid or mechanical valve controlled by a float valve or other liquid level sensing means.
It is an object of this invention to provide a stop valve in which a smaller force is required to operate the pilot valve, and in turn achieving more precise control of the liquid level in a container such as a cistern or fuel tank or container containing corrosive or other pollutant fluids.
A further object of the invention is to provide a stop valve which is less liable to malfunction due to pollutants in the liquid.
A still further object of the invention is to provide a stop valve having means to reduce or eliminate liquid surge and water hammer in the liquid supply line.
DISCLOSURE OF THE INVENTION
In order to overcome one or more of the above objects, there is provided according to the invention a stop valve to terminate the flow of liquid on the liquid reaching a certain level, said stop valve comprising a master valve to control the flow of liquid, said master valve being controlled by a diaphragm valve controlled by a float or other liquid level sensing device in contact with the liquid.
REFERENCES:
patent: 2252078 (1941-08-01), Kohlmeyer
patent: 2253304 (1941-03-01), Toussaint
patent: 2324084 (1943-07-01), Horner
patent: 2328323 (1943-08-01), Bowers et al.
patent: 2382500 (1945-08-01), Owens
patent: 2407761 (1946-09-01), McPherson
patent: 2409890 (1946-10-01), Owens
patent: 2491521 (1949-12-01), Samiran
patent: 2578745 (1951-12-01), Samiran
patent: 2588242 (1952-03-01), Hunter
patent: 2619122 (1952-11-01), Hunter
patent: 2698631 (1955-01-01), Bashark
patent: 2777460 (1957-01-01), Svirsky
patent: 2781772 (1957-02-01), Russell
patent: 3171424 (1965-03-01), Shames et al.
patent: 3194258 (1965-07-01), Grant
patent: 3693649 (1972-09-01), Gordon et al.
patent: 4094327 (1978-06-01), Brandelli
patent: 4295488 (1981-10-01), Book
patent: 4566484 (1986-01-01), Silverman
patent: 4945944 (1990-08-01), Chen
patent: 5829465 (1998-11-01), Garretson
patent: 28492/95 (1995-10-01), None
patent: 297 05 703 (1997-07-01), None
patent: 1 505 097 (1978-03-01), None
patent: 2039345 A (1980-08-01), None
Finnegan Henderson Farabow Garrett & Dunner L.L.P.
Mastavalve Pty. Ltd.
Walton George L.
LandOfFree
Filling stop valve does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Filling stop valve, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Filling stop valve will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2561136