Title:
Safety shutoff device
United States Patent 3920031


Abstract:
A safety shutoff device which includes a fluid supply line; A valve in the supply line with control means for controlling the flow of fluid through the valve; check means for maintaining the control means open; and means, for activating the check means so that the control means can close which include a support housing with an internally mounted plunger, biasing means for urging the plunger towards a receptacle end of the housing, a flexible guide sleeve connected at one end to the valve and at its other end to the housing, and a flexible line passed through the guide sleeve and connected at one end to the plunger and at its other end to the check means whereupon the check means is activated by movement of the plunger in the housing.



Inventors:
MAXFIELD DON A
Application Number:
04/817526
Publication Date:
11/18/1975
Filing Date:
04/18/1969
Assignee:
MAXFIELD; DON A.
Primary Class:
Other Classes:
137/312, 251/74
International Classes:
F17D5/02; F24H9/20; (IPC1-7): F16K31/00
Field of Search:
137/67,75,312 122
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Primary Examiner:
Nelson, Cary M.
Assistant Examiner:
Gerard, Richard
Claims:
I claim

1. In combination, a water line for supplying water to a water storage tank; a valve in said water supply line having control means which allows water to flow through said valve and into said water storage tank when said control means is in an open position; said control means being biased to a closed position check means connected to said valve for maintaining said control means in said open position; a support housing positioned under said water storage tank; to be in communication with water leakage therefrom a plunger movably mounted in said housing; a material receptacle in said housing; a plug of material which changes its dimensions on being contacted with water positioned in said material receptacle for holding said plunger in a predetermined position; biasing means coacting with said plunger for urging said plunger against said plug of material in said material receptacle; and a connecting line coacting with a guide and connected at one end to said plunger and at its opposite end to said check means wherein a predetermined movement of said plunger in said housing moves said check means such that the control means moves to a closed position to restrict the flow of water through said valve.

2. The combination of claim 1 wherein said water storage tank is a water heater.

3. The combination of claim 1 wherein positioning means are connected to said plunger that coact with said housing for holding said plunger in a fixed position in said housing.

4. The combination of claim 1 wherein said connecting line is an elongated flexible wire.

5. The combination of claim 4 wherein said guide is an elongated flexible plastic tube having an interior opening sized to receive said elongated wire.

6. The combination of claim 1 wherein said plug of material is a water-soluble material.

7. The combination of claim 6 wherein said housing is positioned in a drip-pan located under said water supply tank.

8. The combination of claim 6 wherein said housing is an elongated sleeve and said plunger is a piston mounted in one end of said sleeve.

9. The combination of claim 8 wherein positioning are connected to said piston which extend outwardly means are a guide slot in said sleeve.

10. A safety shutoff device for a water storage tank connected to a water supply line for supplying water to said tank, said safety shutoff device comprising a valve in said water line having control means which allows water to flow through said valve and into said water storage tank when said control means is in an open position, said control means being biased to a closed position check means connected to said valve for maintaining said control means in said open position; a support housing positioned under said water storage tank to be in communication with water leakage therefrom; a plunger movably mounted in said housing; a plug of material which changes its dimensions on being contacted with water positioned in said material receptacle for holding said plunger in a predetermined position; biasing means coacting with said plunger for urging said plunger against said plug of material in said material receptacle; and a connecting line coacting with a guide and connected at one end to said plunger and at its opposite end to said check means wherein a predetermined movement of said plunger in said housing moves said check means such that the control means moves to a closed position to restrict the flow of water through said valve.

11. The safety shutoff device of claim 10 wherein said water storage tank is a water heater.

12. The safety shutoff device of claim 10 wherein said connecting line is an elongated flexible wire and said guide is an elongated flexible plastic tube having an interior opening sized to receive said elongated wire.

Description:
BACKGROUND OF THE INVENTION

This invention relates to a safety device for shutting off fluid supply lines.

It is well known that water heaters of the type used in most homes become rusted and are otherwise corroded after long periods of use. After such use the heater's storage tank eventually begins to leak and it must be replaced. Because the storage tank is often placed in a position remote from water drainage means serious damage can result to floors, floor coverings, and to goods that are stored proximate the leaking tank if the tank is allowed to leak for a prolonged period of time. An even more serious problem is encountered with water softener devices having a brine tank which requires periodic flushing. Often times the brine in such tanks overflows or is otherwise spilled to thereby cause very substantial damage. Accordingly, a great need has arisen for an improved safety device which shuts off the water of other fluid supply to the water heater, the brine tank, or the like, when an undesirable leak occurs.

SUMMARY OF THE INVENTION

In its broadest form, the invention comprises a fluid supply line; a valve in said supply line having control means, biased towards a closed position, for controlling the flow of fluid through said valve; check means connected to the valve for holding the control means in an open position; and means for activating the check means to close the control means which comprises a support housing, a plunger movably mounted in said support housing, a material receptacle in said housing, biasing means coacting between said housing and said plunger for urging said plunger towards said material receptacle, a guide connected proximate one end to the housing and proximate its other end to the valve, and a flexible line passed through said guide and connected proximate one end to said plunger and proximate its other end to said check means wherein movement of the plunger in the housing moves said check means and said control means is biased towards its closed position.

In a preferred embodiment of the invention a water soluble material is placed in the activation device's material receptacle for holding the device's plunger in a predetermined position when the water soluble material is out of water contact.

In another embodiment of the invention the liquid supply line is the water supply line for a water heater and the support housing for the means for activating the check means is positioned in a drip-pan located substantially under the water heater.

In still another embodiment of the invention the support housing is an elongated perforated tube and the plunger is a piston slidably mounted in the tube.

A BRIEF DESCRIPTION OF THE DRAWINGS

So that the invention may be more readily understood and carried into effect, reference is made to the accompanying drawings which are offered by way of example only and are not to be taken as limiting the invention, the scope of which is defined by the appended claims which are intended to embrace equivalent structures.

FIG. 1 is a plan elevation view of a conventional water heater equipped with the safety control device of this invention. For purpose of clarity, a portion of the drip-pan positioned under the water heater is shown broken away.

FIG. 2 is a side view of the preferred control valve activation device of this invention.

FIG. 3 is a sectional view taken in the plane of line 3--3 of FIG. 2 looking in the direction of the arrows.

FIG. 4 is a front view of one type of swinging check control valve that is particularly suited for use in this invention.

FIG. 5 is a side view of the swinging check valve shown in FIG. 4.

FIG. 6 is a sectional view taken in the plane of line 6--6 of FIG. 5 and looking in the direction of the arrows.

DESCRIPTION OF THE PREFERRED EMBODIMENT

In FIG. 1 of the drawings there is shown a water heater 10 standing in drip-pan 12 positioned on floor 14. Water is supplied to the heater's water storage tank through supply line 16 which has a conventional shut-off valve 18 and a swinging check valve 20, hereinafter described, provided therein. Check valve 20 can be operated with an activation device, also hereinafter described, to prevent the flow of water through line 16 when water flows into drip-pan 12 and contacts housing 22 of the activation device. Hot water flows from heater 10 through discharge line 24.

The preferred activation device of this invention for activating check valve 20 is illustrated in FIG'S 2 and 3. As shown, the device comprises a housing 22 with a plunger 26 mounted therein proximate one end. The opposite end of the housing serves as a receptacle 28 for material plug 30, hereinafter described. Biasing means such as spring 32 coacts between plunger 26 and the back wall 34 of housing 22 to urge the plunger against plug 30. A flexible line such as wire 36 is affixed at one end to plunger 26 so that when the plunger moves in housing 20 the wire is moved through end port 38 in the housing 22. A flexible guide such as plastic tube 40 is connected to the end 34 of housing 22 in a position so that wire 36 passes therethrough.

Preferably housing 22 is an elongated tube with a plurality of perforations 42 provided therein proximate receptacle end 28 so that a liquid can easily flow into contact with plug 30. A lever or handle 44 can be attached to plunger 26 for urging the plunger to move away from plug 30 so that a replacement plug can be placed in the housing 22. When an activation lever is provided, as described, a guide slot 46 is provided in the housing so that plunger 26 can reciprocate back and forth therein. An offset slot 48 can also be provided in communication with slot 46 so that handle 44 can be held in a fixed position in housing 22 even when a plug 30 is not positioned in the tube's receptacle end 28. Removable cap 50 is attached to the housing's receptacle end 28 through the use of threads, or the like, so that plug 30 can be replaced when required. As an alternative to a removable cap, an opening can be provided in the sidewall of housing 22 proximate receptacle 28 so that plug 30 can be placed directly in the receptacle through the opening in the housing.

FIG'S. 4 through 6 illustrate one type of safety check valve 20 that can be used in this invention. As shown, the valve comprises a housing 52 having a rotatably mounted control flap 54 positioned therein that is urged against valve seat 56 with biasing means such as coiled spring 58 attached to housing 52 and control plate 60. The control plate is in turn fixedly attached to shaft 62 which is rotatably mounted in housing 52. Flap 54 is connected to shaft 62 so that it can be moved from an open position to a closed position, and visa versa, by merely rotating the shaft back and forth. Notch 64 is positioned in control plate 60 to coact with one end 68 of shaft 66 which is connected with bracket 70 to valve housing 52. The other end 72 of shaft 66 is connected to line 36 so that when said line is activated by the movement of plunger in housing 22 shaft 66 is rotated to move its end 68 away from the notch 64 in control plate 60 and spring 58 urges flap 54 to move to its closed position against valve seat 56. End 74 of flexible tube 40 is fixedly connected to valve housing 52 with bracket 76 to ensure activation of flap 54 whenever plunger 26 moves a predetermined distance in housing 22.

In operation, the receptacle end 28 of housing 22 is filled with a material plug 30 such as sugar, salt, or the like, which dissolves when contacted with a predetermined fluid, or a material such as a dry sponge which can easily change its dimensions when contacted with said fluid. When the housing is fitted with a filling cap 50 the cap is securely affixed to housing 22 and the thus filled housing is then placed in a position calculated to come in contact with a predetermined fluid if said fluid is allowed to run free. If, for example, the device of this invention is to be used for closing a water heater's supply line when the heater's storage tank begins to leak, housing 22 can be placed under the water heater's tank, preferably in a drip-pan. Then when the heater's tank begins to leak the material in the receptacle end 28 of housing 22 is either dissolved, softened, or expanded, whereupon plunger 26 moves in the housing towards its capped end and wire 36 is pulled through tube 40 thereby rotating shaft 66 releasing control flap 54 to be urged into contact with valve seat 56 and the water supply to water heater 10 is shut off.