Automatic flood prevention system

• US 6,675,826 B1
• Filed: 01/25/2003
• Issued: 01/13/2004
• Est. Priority Date: 01/25/2003
• Status: Expired due to Fees

• Current Assignee: Newman Family Partnership Limited
• Original Assignee: Newman Family Partnership Limited
• Inventors: Newman, Frederic M., Sites, Richie D.
• Primary Examiner(s): Walton, George L.
• Application Number:
  US10/351,037
• Time in Patent Office: 353 Days
• Field of Search: 137/15.11, 137/240, 137/312, 137/387, 137/392, 137/558, 137/624.11, 137/624.12, 137/624.13, 733/04.R, 733/13, 200/61.04, 200/61.05, 340/604, 340/605, 340/620, 122/504, 122/504.2, 122/507, 361/178
• US Class Current: 137/312
• CPC Class Codes: F16K 31/082 using a electromagnet and a permanent magnet
• CPC Class Codes: F16K 31/404 the discharge being effected through the diaphragm and being blockable by an electrically-actuated member making contact with the diaphragm
• CPC Class Codes: H01H 35/42 Switches operated by change of humidity
• CPC Class Codes: Y10T 137/0452 Detecting or repairing leak
• CPC Class Codes: Y10T 137/5762 With leakage or drip collecting
• CPC Class Codes: Y10T 137/7306 Electrical characteristic sensing
• CPC Class Codes: Y10T 137/8342 Liquid level responsive indicator, recorder or alarm
• CPC Class Codes: Y10T 137/86397 With independent valve controller
• CPC Class Codes: Y10T 137/86405 Repeating cycle

Abstract

A flood prevention system includes a double-latching solenoid valve that shuts off a water supply line in response to a moisture sensor detecting a leak in a plumbing system. The double-latching feature provides the solenoid'"'"'s plunger with two positions of equilibrium. This minimizes electrical power consumption so that the flood prevention system can be battery operated. To minimize a buildup of hard water deposits, the valve includes a flexible diaphragm and is cycled periodically regardless of whether flooding occurs. The sensor includes multiple methods of mounting to a floor.

Claims

1. A flood prevention system responsive to moisture on a floor, comprising:

a valve body defining a water inlet and a water outlet;

a diaphragm disposed within the valve body and being selectively movable to an open position and a closed position, wherein the diaphragm in the open position places the water inlet in fluid communication with the water outlet, and the diaphragm in the closed position provides a flow obstruction between the water inlet and the water outlet;

a double-latching solenoid attached to the valve body and having a plunger that is selectively movable to a first equilibrium position and a second equilibrium position, wherein the plunger in the first equilibrium position causes the diaphragm to move to the closed position, and wherein the plunger in the second equilibrium position causes the diaphragm to move to the open position;

a moisture sensor having an electrical conductivity that changes in response to being exposed to moisture, whereby the moisture sensor provides a moisture signal that that varies with the electrical conductivity;

a touch-and-hold fastener attached to the moisture sensor;

an adhesive on the touch-and-hold fastener;

wherein the adhesive can adhere to the floor while the touch-and-hold fastener facilitates removably attaching the moisture sensor to the floor; and

a controller having an input, an output, and a manual reset with the input being electrically coupled to the moisture sensor to receive the moisture signal and the output being electrically coupled to the double-latching solenoid, wherein the controller responds to the moisture signal reaching a predetermined limit by providing at the output a first momentary valve-closing signal that shifts the plunger to the first equilibrium position, and the controller responds to actuation of the manual reset by providing at the output a second momentary valve-opening signal that shifts the plunger to the second equilibrium position.

2. The method of claim 1, wherein the first momentary voltage signal has a polarity that is opposite that of the second momentary voltage signal.

3. The flood prevention system of claim 1, wherein the moisture sensor defines a screw-receiving mounting hole that overlays the touch-and-hold fastener, whereby the screw-receiving mounting hole further facilitates attaching the moisture sensor to the floor.

4. The flood prevention system of claim 1, further comprising a timer that signals the controller to periodically cycle double-latching solenoid valve even though the moisture sensor may not have sensed moisture.

5. The flood prevention system of claim 1, further comprising a battery that provides electrical power to the controller.

6. A method of controlling a double-latching solenoid valve to prevent a water supply line from completely flooding a floor, comprising:

connecting the double-latching solenoid valve to the water supply line;

opening the double-latching solenoid valve by providing a first momentary voltage signal thereto;

discontinuing the first momentary voltage signal while leaving the double-latching solenoid valve open;

sensing moisture adjacent to the floor;

in response to sensing moisture on the floor, closing the double-latching solenoid valve by providing a second momentary voltage signal thereto;

discontinuing the second momentary voltage signal while leaving the double-latching solenoid valve closed; and

periodically cycling the double-latching solenoid valve during a period when substantially no moisture is sensed, whereby the periodic cycling helps loosen hard water deposits that may accumulate inside the double-latching solenoid valve.