Not Applicable
1. Field of the Invention
The present invention relates to devices that automatically limit fluid flow. Specifically, the present invention relates to devices that electronically shuts off uncontrolled primary fluid flow after a predetermined volume of continuous fluid flow is detected, limit consumption thereafter, and automatically resets the device.
2. Description of the Related Art
Flow metering devices are frequently employed to terminate the flow of a fluid after a predetermined amount of fluid has passed, or when the flow exceeds the normal limits. With water consumption becoming limited in many areas, it is increasingly important to detect and prevent over consumption or uncontrolled water usage.
Prior art teaches flow control devices designed to stop fluid flow that has continued for a predetermined amount of time. While having fluid consumption limited by time is helpful in certain situations, such as lawn care, a single predetermined length of time for all fluid usages is impractical. For example, the amount of time hat one desires a garden to be watered may be different than the amount of time needed to run a dishwasher. Thus, it would be an improvement to the art to have a device that stops uncontrolled fluid flow based on actual usage rather than time.
Prior art also teaches flow control devices that require a manual reset. However, requiring a manual reset is problematic in the event that the user is not present to reset the system. Therefore, it would be a further improvement in the art to provide an automatic reset to a flow control device.
Mechanical devices for limiting fluid flow based on volume and time are known in the art. However, these devices are complex in operation and require multiple parts, as well as requiring dedicated space for operation. Therefore, it would be an improvement to the art to have a control line that permits nominal fluid flow to the device outlet after the valve has shut off and that further permits the automatic reset of the flow control device after the point of uncontrolled flow, such as an open faucet or a leak, has been closed. It would be a further improvement over the prior art to provide an electronically controlled device that reduces the number of components, thereby reducing the space needed for the flow control device.
Other features and advantages of the invention will be apparent from the following description, the accompanying drawing and the appended claims.
Referring to
The flow control apparatus 100 comprises main supply line 101, a first pressure transducer 130, a rotary meter 110, control line 332, intermediate valve 220, a second pressure transducer 230, and a digital controller 150. A first valve 103 is depicted adjacent the device inlet 102, and a second valve 105 is depicted adjacent the device outlet 104. Main supply line 101 provides fluid communication of a primary stream 310 through device inlet 102, rotary meter 110, and device outlet 104. Control line 332 provides fluid communication of a secondary stream 300 from control line inlet 333 to control line outlet 334.
Opening first valve 103 allows stream 310 to flow into main supply line 101. First pressure transducer 130 monitors the pressure of the incoming stream 310. First pressure transducer 130 converts the pressure into digital format and transmits the digital signal to digital controller 150 via an electronic connection. Primary stream 310 ten enters rotary meter 110.
Rotary meter 110 provides revolution as a result of fluid flow through rotary meter 110. Rotary meter 110 may include a plurality of impeller blades 112, an impeller shaft 114, and an impeller housing 116. Impeller housing 116 rotationally retains impeller shaft 114. Impeller shaft 114 extends through impeller housing 116 to a point external of impeller housing 116. A shaft seal prevents fluid leakage at the interface of impeller shaft 114 and impeller housing 116. Impeller shaft 114 interfaces with pulse transducer 400 at the external shaft end.
Primary stream 310 enters rotary meter 110. As primary stream 310 flows through impeller housing 116, force applied to impeller blades 112 causes impeller blades 112 and impeller shaft 114 to rotate about impeller axis 125. Impeller shaft 114 induces rotation to pulse transducer 400, which translates rotations by impeller shaft 114 to a digital signal. This signal is transmitted to digital controller 150 via an electronic connection.
Primary stream 310 exits rotary meter 110, and continues flowing through main supply line 101, provided intermediate valve 220 remains in the open position. Intermediate valve 220 is controlled by solenoid 210. Solenoid 210 is electronically connected to digital controller 150 and receives instructions from digital controller 150 on whether to open or close intermediate valve 220. Should a programmed set point actuate solenoid 210 into closing intermediate valve 220, the flow of primary stream 310 will terminate at intermediate valve 220, thereby terminating rotation of rotary meter 110.
Provided intermediate valve 220 is open, primary stream 310 continues flowing through main supply line 101, passing second pressure transducer 230. Second pressure transducer 230 is electronically connected to digital controller 150 and provides a second fluid pressure monitoring point. Therefore, the overall pressure of primary stream 310 is monitored across the system, at first pressure transducer 130, proximate device inlet 102, and at second pressure transducer 230, between intermediate valve 220 and second valve 105, or point of use. Second pressure transducer 230 is used to reset the system, depending on the pressure of primary stream 310 versus the preset pressure of digital controller 150.
Closure of second valve 105 prevents further flow by primary stream 310 through main supply line 101, and consequently through device outlet 104. Simultaneously, flow is stopped through rotary meter 110. Without flow through rotary meter 110, rotation of impeller shaft 114 ceases. Second valve 105 serves as the control point for primary stream 310 to exit apparatus 100. Second valve 105 is presented as devices such as a faucet.
A control line 332 directs a control steam 330 from device inlet 102 to a control line outlet 338. Control line 332 is in fluid communication with primary line 101, and includes a control valve 335. Control valve 335 provides adjustability of the control steam 300 through control line 332 so the control steam 330 is a nominal flow rate. Shutdown solenoid 337 is located downstream form control valve 335. If a leak is present, and flow should continue through flow control apparatus 100, shutdown solenoid 337 provides a means to detect the leak and terminate all water flow through flow control apparatus 100.
In operation, pulse transducer 400 monitors the flow rate and usage. If these values reach the predetermined set point, solenoid 210 closes intermediate valve 220, thereby eliminating flow downstream intermediate valve 220. At this point, rotation of rotary meter 110 should decrease due to reduced water pressure and flow. The water pressure and flow will not completely cease as water remains directed through control line 332. If pulse transducer 400 detects a pressure decreases to a value to a value lower than the programmed set point, the system will reset itself. Further, if second valve 105 is manually closed, the system will reset after a predetermined period of time has elapsed. However, if second valve 105 is not manually closed, digital controller 150 transmits a signal to shutdown solenoid 337, which will terminate all flow of primary stream 310. Thereafter, primary stream 310 cannot flow through main supply line 101 until the system is manually reset by depressing a reset switch on digital controller 150.
Because control line inlet 333 is intermediate rotary meter 110 and intermediate valve 220, a nominal flow of control steam 300 continues through control line 332 and out control line outlet 334. The continued flow of secondary stream 310 bypasses intermediate valve 220. This allows pressure to build on second pressure transducer 230. When second valve 105 is closed and the pressure reaches a predetermined set point, digital controller 150 instructs solenoid 210 to reopen intermediate valve 220, thereby resuming flow downstream intermediate valve 220.
Transformer 800 is electronically connected to digital controller 150. Digital controller 150 is programmable to accept set points such as total volume, schedule usage hours, automatic reset points, history times, and water actuation switch. Digital controller 150 is preferable mountable on vertical surfaces, but may also be mounted in alternative configurations. Digital controller 150 preferable provides an interface for connecting with a computer. Additionally, various appliances may be linked to digital controller 150, such that power is terminated to these appliances when primary stream 310 is terminated. This is particularly useful for appliances such as dishwashers and washing machines, which require water to operate.
The determination of the applicable maximum fluid flow set point initially beings with a decision 402 that determines whether there is any fluid flow through main supply line 101 of the fluid consumption device 100 depicted in
Once the counter has been activated 406, decision 408 determines whether the building is occupied. Determining whether the building is occupied can be achieved either through use of motion sensors, or through the use of a timer set to typical hours of occupation. If decision 408 determines that the building is occupied, the set point is set at a value 412, represented as “X” in
As previously stated, if decision 402 determines that there is no fluid flow, a leak program executes. Decision 420 determines whether the difference in pressure across the main supply line 101 is greater than the pressure preset value. The difference in pressure across main supply line 101 is determined by measuring the differences in pressures between first pressure transducer 130 and second pressure transducer 230. If the difference in pressure is greater than the pressure preset value, the operation will proceed to decision 422, which determines whether the building is occupied. Alternatively, if decision 420 determines that the difference in pressure is not greater than the pressure preset value, then the counter will reset to zero 421 and the operation will return to decision 402.
If decision 422 determines that the building is not occupied, a timer will activate 424, and the first and second valves 103 and 105 will be closed 426. Fluid consumption device 100 preferable remains in this configuration until fluid consumption device 100 is reset. Alternatively, if decision 433 determines that the building is occupied, first and second valves 103 and 105 remain open, and a timer will activate 430. If the timer exceeds the preset value, first and second valves 103 and 105 will be closed 432.
The operation 500 initially beings with a decision 502 that determines whether the fluid flow through main supply line 101 is greater than the established set point 400 outlined in
Decision 506 determines whether the manual reset button has been reset. Providing a manual reset button permits the user to quickly override the determined set point 400, should a larger amount of fluid be necessary. If the manual reset button has been has been reset, decision 506 instructs digital controller 150 to open first valve 514 (first valve 103 in
Decision 508 determines whether the fire alarm has been activated, thereby permitting the fluid consumption device 100 to continue to provide fluid in circumstances where a fire may require a volume of fluid that exceeds the allotted volume stipulated in set point determination 400. If the fire alarm has been activated, decision 508 instructs digital controller 150 to open first valve 414 (first valve 103 in
The operation 600 initially beings with a decision 602 that determines whether the first valve 103 is closed. If decision 602 determines that the first valve 103 is not closed, the counter continues to monitor the fluid flow 604, and returns to operation 500. Alternatively, if decision 602 determines that the first valve 103 is closed, a series of coinciding events occur, designated as “A” and “B” in
Referring to group A, operation 600 proceeds to decision 606, which determines whether the pressure measured by shutdown solenoid 337 is less than the preset value. The preset value is a predetermined value entered into digital controller 150. If decision 606 determines that the pressure is not less than the preset value, the counter continues to monitor the fluid flow 604, and the operation returns to operation 500. Alternatively, if decision 606 determines that the pressure is greater than the preset value, operation 600 proceeds to decisions 608.
Decision 608 determines whether the downstream relays are on or off. As previously stated, digital controller 150 can terminate power to the downstream relays if it is determined that the flow has exceeded the permitted value. The downstream relays can include common fluid-consuming appliances such as washing machines and dishwashers. If decision 608 determines that the relays are on, the counter continues to monitor the fluid flow 604, and the operation returns to operation 500. Alternatively, if decision 608 determines that the downstream relays are off, operation 600 resets the counter.
Referring to group B, operation 600 also proceeds from decision 602 to start the timer 612 when decision 612 determines that the first valve 103 is closed. Once the timer has started, operation 600 proceeds to decision 614, wherein it is determined whether the timer exceeds the preset limit specified in digital controller 150. If decision 614 determines that the timer has not exceeded the limit, the second valve (depicted as 210 in
The foregoing description of the invention illustrates a preferred embodiment thereof. Various changes may be made in the details of the illustrated construction within the scope of the appended claims without departing from the true spirit of the invention. The present invention should only be limited by the claims and their equivalents.
This application claims the benefit of U.S. Provisional Patent Application No. 60/596,186 entitled, “Digitally Controlled Fluid Limiting Apparatus, ” filed on Sep. 9, 2005 in the United States Patent and Trademark Office.
Number | Date | Country | |
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60596168 | Sep 2005 | US |