Leak detection and control

• US 7,574,896 B1
• Filed: 11/27/2006
• Issued: 08/18/2009
• Est. Priority Date: 09/18/2003
• Status: Active Grant

• Current Assignee: Michigan Aqua Tech Incorporated
• Original Assignee: Michigan Aqua Tech Incorporated
• Inventors: Cooper, Ralph W.
• Primary Examiner(s): FITZGERALD, JOHN P
• Application Number:
  US11/604,636
• Time in Patent Office: 995 Days
• Field of Search: 73/40, 73/405.R, 137/15.11, 340/605, 702/51
• US Class Current: 73/40.50R
• CPC Class Codes: G01M 3/2815 using pressure measurements

Abstract

Fluid leaks can be detected and controlled in a pressurized piping system. Apparatus for this includes control logic; in communication with the logic, a flow detector and/or a pressure detector, and a control valve. One or more of the following is or are provided also: the flow and pressure detectors are both present, and both as single units; the control logic, the flow and/or pressure detector(s) and the control valve are in close proximity to one another; and the control valve has a baseline condition of being shut off. A remote control device can remotely interact with the control logic. Pressure decay and/or flow properties can be employed. The fluid can be water as, for example, in a residential, commercial or institutional system.

Claims

1. A leak detection apparatus for detecting and controlling a leak in a pressurized piping system, which comprises:

control logic;

both of one and only one flow detector in communication with said logic, and one and only one pressure detector in communication with said logic; and

a control valve in communication with said logic;

wherein at least one of the following additional features is also provided;

the control logic, both of one and only one flow detector and one and only one pressure detector, and the control valve are in close proximity to one another; and

the control valve has a baseline condition of being shut off.

2. The apparatus of claim 1, wherein a remote control device is provided, which can remotely interact with the control logic, and allows for remote reset and override capability as well as a leak test on demand at any time from a remote or proximate location to insure proper operation.

3. The apparatus of claim 1, wherein the additional feature of the control valve having a baseline condition of being shut off is present.

4. The apparatus of claim 3, wherein a remote control device is provided, which can remotely interact with the control logic.

5. In combination, the apparatus of claim 3 and a pressurizable piping system to which the apparatus is connected in fluid communication with the system for delivery of the fluid.

6. The combination of claim 5, wherein the fluid is water;

the piping system is brachiated; and

a single apparatus is connected.

7. The apparatus of claim 1, wherein the additional feature is present of the control logic, both of one and only one flow detector and one and only one pressure detector, and the control valve being in close proximity to one another.

8. The apparatus of claim 7, wherein a remote control device is provided, which can remotely interact with the control logic.

9. In combination, the apparatus of claim 7 and a pressurizable piping system to which the apparatus is connected in fluid communication with the system for delivery of the fluid.

10. The combination of claim 9, wherein the fluid is water;

the piping system is brachiated; and

a single apparatus is connected.

11. The apparatus of claim 1, wherein both additional features of

the control logic, both of one and only one flow detector and one and only one pressure detector, and the control valve being in close proximity to one another;

and

the control valve having a baseline condition of being shut off

are present; and

wherein the apparatus can generally discriminate between controlled and uncontrolled pressure decay at very low flow rates.

12. The apparatus of claim 11, wherein a remote control device is provided, which can remotely interact with the with the control logic.

13. In combination, the apparatus of claim 11 and a pressurizable piping system to which the apparatus is connected in fluid communication with the system for delivery of the fluid.

14. The combination of claim 13, wherein the fluid is water;

the piping system is brachiated;

a single apparatus is connected; and

the controlled pressure decay at very low flow rates is represented by replenishment in a refrigerator'"'"'s ice maker, and the uncontrolled pressure decay at very low flow rates is represented by an unwanted leak.

15. In combination, the apparatus of claim 1 and a pressurizable piping system to which the apparatus is connected in fluid communication with the system for delivery of the fluid.

16. The combination of claim 15, wherein the fluid is water;

the piping system is brachiated; and

a single apparatus is connected.

17. A leak detection apparatus for detecting and controlling a leak in a pressurized piping system for water, which comprises, in close proximity to one another the following:

control logic;

both of;

one and only one flow detector in communication with the control logic, which can be set to detect minimal water flow; and

one and only one pressure detector in communication with the control logic, which can be monitored in a pressure decay test initiated by the control logic; and

a control valve in communication with the control logic, which has a baseline condition of being off.

18. The apparatus of claim 17, which further comprises the following features:

a user demand set to establish a maximum user demand time period;

a fault indicator, which can be activated through signals from the control logic whenever a demand flow has exceeded a preset value or when a low rate count exceeds a set value to indicate why the apparatus has stopped flow of the water;

a leak-detected indicator, which is activated when a leak test has failed or when a low rate count exceeds a set value to indicate why the apparatus has stopped flow of the water;

a reset to restart the apparatus after shut down;

a power-on indicator to indicate main control power on;

a demand indicator, which is activated when the water is flowing; and

a leak-testing indicator, which is activated while a leak test is being conducted.

19. The apparatus of claim 18, which further comprises the following:

a control panel or box, which contains the following;

the control logic, said both flow detector and pressure detector, and said control valve; and

manual valves, as follows;

a first valve, which is normally closed during operation, but can be opened for by-pass mode; and

second and third valves, which are mounted on test line sections of the apparatus; and

a remote control;

and wherein;

the user demand set includes a dial;

the fault indicator, the leak-detected indicator, the power-on indicator, the demand indicator, and the leak-testing indicator include lights; and

the reset includes a button.

20. The apparatus of claim 17, which further comprises the following:

A. User inputs associated with the control logic, which include the following inputs controllable from a panel front;

a system reset button; and

a flow guard knob, which is a variable resistor type with control in minutes; and

a wireless remote, which also can provide for user input;

B. User monitoring outputs located on the panel front and associated with the control logic, which include the following;

a power-on lamp;

a flow guard lamp;

a flow fault lamp;

a leak guard lamp; and

a leak fault lamp; and

user monitoring outputs located on the remote;

C. Standard inputs with respect to terminal strip wiring associated with a control box and the control logic, which include the following;

for power, 120-V AC, from a cord;

for the flow detector, a flow switch with normally open contact, which closes contact at approximately 0.21 gpm on increasing flow; and

for the pressure detector, a pressure switch with normally closed contact, which opens contacts at approximately a 30-psig value on increasing pressure;

D. Standard output with respect to terminal strip wiring associated with the control box and control logic, which includes that to the control valve, 120-V AC 60-Hz, normally closed, full port;

E. Auxiliary inputs with respect to optional terminal strip wiring associated with the control box and control logic, which include the following;

an external reset switch, which allows the user to reset a fault condition from a hardwired switch away from the control panel, and which has normally open contact with multiple switches able to be wired in parallel; and

a flow guard override switch, which can indicate that a long-demand item needs water, normally open contact input;

F. Auxiliary outputs with respect to optional terminal strip wiring associated with the control box and control logic, which include the following;

a fault lamp, a security system link normally open, closed on fault, which requires power be supplied to the apparatus for operation;

a power lamp, 5-V DC, which is for service; and

a ground for shielding;

G. Non-stored configuration settings with respect to terminal strip wiring associated with the control box and control logic, which include that from a flow guard timer set by the flow guard knob, which is maximum continuous time that water can run, except when a flow guard override signal has been received, which is a user-adjustable factor;

H. Stored configuration settings, electrically erasable permanent read only memory (EEPROM), with respect to terminal strip wiring, associated with the control box and control logic, which include the following;

a leak test cycle timer, which times intervals between leak tests, and which can be programmably adjustable from the remote to a 1-minute to 100-minute value;

a leak test decay timer, which times duration of the leak test, and which can be programmably adjustable from the remote to a 1-minute to 100-minute value;

a flow guard override timer, which is an auxiliary input that times maximum duration water can run when the flow guard timer is being overridden, and which can be programmably adjustable from the remote to a 1-hour to 10-hour value;

a surge flow timer, which can time minimum time allowed to establish a flow signal, which is the time allowed to establish a verified flow where a flow signal pulse from the flow switch is expected when the piping system repressurizes and for which the flow switch remains activated for the adjustable time period in order for a logical one-flow signal to be generated, and which can be programmably adjustable from the remote to a 1-second to 10-second value;

a surge window timer, which controls time allowed for flow verification, which is maximum time allowed for a verified flow signal to be established and begin the next programmable step, and which can be programmably adjustable from the remote to a 1-second to 10-second value;

a low flow rate timer, which determines possible low flow represented by drip-watering of plants or making ice in a freezer versus a leak, which is a time window beginning a leak test when a low pressure condition is considered a low flow instead of a leak, and which can be programmably adjustable from the remote to a 1-second to 20-second value; and

a configuration timer, which is for limiting time allotted to complete programming of the apparatus;

I. Limits associated with the control logic, which include the following;

a leak failure limit, which is the number of leak test failures that it takes for the apparatus to go to a leak fault status indicated by the leak fault lamp, and which can be programmably adjustable from the remote to a 1-count to 10-count value; and

a low flow failure limit, which is the number of low flow failures that it takes for the apparatus to go to a flow fault status indicated by the flow fault lamp, and which can be programmably adjustable from the remote to a 1-count to 10-count value.

21. The apparatus of claim 20 having a further feature, which includes a last known state program that, upon reset or restarting of the apparatus, returns the control logic to the last step at which it had been functioning previously, in which the state is updated in EEPROM when a fault occurs or is cleared.