Fluid handling – Liquid level responsive or maintaining systems – By float controlled valve
Reexamination Certificate
2000-12-20
2002-09-10
Walton, George L. (Department: 3753)
Fluid handling
Liquid level responsive or maintaining systems
By float controlled valve
C137S409000, C137S448000
Reexamination Certificate
active
06446665
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to a backwater valve for use in liquid flow lines to prevent a reversing of the flow stream.
BACKGROUND OF THE INVENTION
In U.S. Pat. No. 5,406,972 which issued 1995, Gabe Coscarella disclosed a backwater valve with a pivotally mounted closure gate. A float was mounted to the closure gate. The closure gate sat in the liquid stream. As the liquid stream rose the float caused the closure gate to float into a closed position.
The backwater valve described in the Coscarella patent was useful in a variety of applications and has come into widespread commercial usage. There were some applications encountered, however, in which it was not desirable to have the closure gate positioned in the liquid stream.
SUMMARY OF THE INVENTION
What is required is an alternative configuration of backwater valve in which the closure gate does not float in the liquid stream.
According to the present invention there is provided a backwater valve which includes a body having a flow passage extending therethrough with an inlet side and an outlet side. A closure gate is pivotally mounted within the body above the inlet side of the flow passage. The closure gate has an open position above the flow passage and a closed position blocking the inlet side of the flow passage. A float activated locking member is mounted on the body. The locking member has a locking position and a release position. In the locking position, the locking member engages and holds the closure gate in the open position. The float activated locking member is influenced by liquid rising in the body whereby the locking member is carried to the release position when the liquid rises above a preset level and upon release the closure gate closes by force of gravity.
With the backwater valve, as described above, the closure gate is held in the open position out of the liquid stream by the locking member. When liquid starts to fill the valve body, the rising liquid carries the locking member to the release position. The locking member then releases the closure gate which falls by force of gravity to the closed position to prevent a reversal of liquid flow back through the inlet side of the flow passage.
REFERENCES:
patent: 194676 (1877-08-01), Hansen
patent: 199696 (1878-01-01), Dikeman
patent: 217431 (1879-07-01), Tilton
patent: 271644 (1883-02-01), Lowrie
patent: 289108 (1883-11-01), Johnson
patent: 384396 (1888-06-01), Shepherd
patent: 384397 (1888-06-01), Shepherd
patent: 424580 (1890-04-01), Shepherd
patent: 500453 (1893-06-01), Wright
patent: 1031567 (1912-07-01), Miller
patent: 1113648 (1914-10-01), Karlson
patent: 1183692 (1916-05-01), Strout
patent: 1205199 (1916-11-01), Healy
patent: 1584666 (1926-05-01), Shockley
patent: 1606396 (1926-11-01), Blom
patent: 1861397 (1932-05-01), Khun
patent: 1864443 (1932-06-01), Khun
patent: 1924498 (1933-08-01), House
patent: 2013188 (1935-09-01), Reinhardt
patent: 2266930 (1941-12-01), Watson
patent: 2290461 (1942-07-01), Young
patent: 2292509 (1942-08-01), Carson
patent: 2638178 (1953-05-01), McRill
patent: 2695072 (1954-11-01), Hauslein
patent: 2928410 (1960-03-01), Del Vecchio
patent: 3176707 (1965-04-01), Wilson
patent: 3395721 (1968-08-01), Shibata
patent: 3626521 (1971-12-01), Delco
patent: 3781920 (1974-01-01), Browne et al.
patent: 3933444 (1976-01-01), Kilgore
patent: 3974654 (1976-08-01), Mirto, Jr.
patent: 4324506 (1982-04-01), Steinke
patent: 4475571 (1984-10-01), Houston, Jr. et al.
patent: 4503881 (1985-03-01), Vecchio
patent: 4544027 (1985-10-01), Goldberg et al.
patent: 4787103 (1988-11-01), Endo
patent: 4844610 (1989-07-01), North, Jr.
patent: 4891994 (1990-01-01), Barba
patent: 5234018 (1993-08-01), Grachal et al.
patent: 5406972 (1995-04-01), Coscarella et al.
patent: 5669405 (1997-09-01), Engelmann
patent: 5819791 (1998-10-01), Chronister et al.
patent: 5934313 (1999-08-01), Brothers et al.
patent: 5947152 (1999-09-01), Martin et al.
patent: 2114602 (1997-07-01), None
Product information for the ZURN Z-1091 Backwater Valve, Zurn Industries Limited, 1 page, dated at least as early as Dec. 2000.
Davis & Bujold P.L.L.C.
Walton George L.
LandOfFree
Backwater 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 Backwater valve, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Backwater valve will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2902331