CROSS-REFERENCE TO RELATED APPLICATION

The present application is a continuation of U.S. patent application Ser. No. 11/122,791 filed May 4, 2005 which in turn claims the benefit of U.S. provisional patent application No. 60/568,427 filed on May 4, 2004, both of which are hereby incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates generally to valve diagnostics and in particular to a distribution valve monitor and to a distribution valve incorporating the same.

BACKGROUND OF THE INVENTION

Distribution valves are known in the art and have been used in both irrigation and wastewater treatment systems to allow fluid to be effectively distributed over large areas. One common mechanical liquid distribution valve (MLDV) is manufactured by K-Rain Corporation of Florida. This MLDV includes an enclosure having a single inlet and a plurality of outlets, typically four (4), five (5) or six (6). A plunger is centrally disposed within the enclosure and is secured to a rubber plate that can be moved to seat against the valve bottom. The plate has an aperture therein that aligns with one of the outlets. The plunger accommodates a spring element that acts on the plate to force it away from valve bottom. When fluid under pressure is supplied to the inlet, the force of the fluid moves the plunger down through a cam causing the plunger and plate to rotate and seat the plate against the valve bottom with the aperture in the plate in alignment with one of the outlets. When the fluid pressure supplied to the inlet drops, the plate and plunger are biased back upwardly thereby moving the plunger back through the cam and causing the plunger and plate to rotate. When fluid under pressure is again supplied to the inlet, the plunger and plate move downwardly against the spring bias and rotate thereby to seat the plate against the valve bottom with the aperture in the plate in alignment with the next outlet. Cycling fluid pressure to the MLDV in this manner therefore allows the incoming fluid to be distributed to the outlets of the MLDV in succession.

FIG. 1 shows a conventional arrangement for an MLDV 10. As can be seen, the MLDV 10 includes an inlet 12 connected to a pump 14 via a conduit 16. The pump 14 draws fluid from a fluid source such as a reservoir or tank 18 via a conduit 20. The pump 14 is operated to cyclically supply fluid under pressure to the inlet 12 of the MLDV 10 at intervals. The outlets 24 of the MLDV 10 are connected to a plurality of discharge points 26 positioned at different zones by conduits 28. During typical operation, the MLDV 10 couples the outlets 24 to the inlet 12 in succession so that fluid flow to the discharge points 26 cycles through a desired pattern allowing the fluid to be effectively distributed.

Although MLDVs serve a valuable and useful purpose, they are subject to failure and/or improper operation. Over time, MLDVs can be worn resulting in failure. Rocks or other debris may become lodged in the MLDV internal mechanisms thereby preventing the MLDVs from moving through their cycles. Installation errors may also result in improper MLDV operation. Furthermore, sub-optimal pump timing, freezing, insufficient fluid flow or inadequate fluid pressure and/or air in the conduits may result in inconsistent MLDV operation and skipping.

Regardless of the environment in which MLDVs are being used, it is important for the MLDVs to operate properly so that fluid is applied uniformly throughout the various zones. Failure to do so can be problematic. In irrigation systems, failure of MLDVs may result in zones being supplied with excess or insufficient water. In farming environments, excess water in any particular zone may reduce crop yields due to leaching of plant nutrients, increase disease incidence and/or fail to stimulate growth of commercially valuable parts of crops. Insufficient watering in any particular zone may lead to high soil moisture tension that creates plant stress and reduces crop yield. In other environments such as for example on golf courses where MLDVs are used to distribute water to greens, failure or skipping of the MLDVs may result in extensive damage.

When used in wastewater treatment and/or disposal systems, failure of MLDVs is of even more concern due to the potential environmental impact resulting from such a failure. Even distribution of treated effluent across dispersal zones is essential to ensure that the treated effluent is naturally absorbed into the environment. In wastewater treatment systems employing filter media such as for example, soils, textile filters etc., if the filter media is overloaded, its ability to treat effluent may be adversely affected potentially resulting in serious environmental problems including groundwater contamination and surfacing/breakout of untreated effluent.

Unfortunately, to-date there has been no convenient way of determining whether MLDVs are operating properly. Presently, in order to determine proper MLDV operation, it is necessary to visually inspect each MLDV. During inspection, the system must be partially dismantled so that the MLDV can be cycled by manually turning the inlet fluid pressure on and off and visually monitoring the fluid output of the MLDV. As will be appreciated, inspecting MLDVs in this manner is time consuming and impractical especially in systems employing significant numbers of MLDVs. As a result, there is a need for improved methods of monitoring MLDV operation.

It is therefore an object of the present invention to provide a novel distribution valve monitor and a novel distribution valve incorporating the same.

SUMMARY OF THE INVENTION

According to one aspect, there is provided a distribution valve monitor to monitor the operation of a distribution valve of the type having an inlet and a plurality of outlets, which couples the outlets to the inlet according to a desired fluid distribution pattern. The monitor includes a plurality of non-contact sensors disposed at spaced location about the distribution valve to sense activation of the valve to different operating conditions. A controller communicates with the sensors and records data representing the operation of the distribution valve. The recorded data is examined to detect improper operation and/or failure of the valve.

In one embodiment, an alarm signal is generated when the controller determines that the operation of the valve has been significantly compromised i.e. the valve has jammed or skips. The sensors are hall effect sensors and detect the presence of magnets disposed within the valve as the magnets move during cycling of the valve. The sensors include a plunger sensor to sense reciprocation of a plunger within the distribution valve and rotation sensors to sense rotation of a plate within the distribution valve. A magnet is disposed on the plunger and on the plate. The distribution valve monitor can be retrofitted to an existing distribution valve or incorporated into the distribution valve thereby to form an integrated unit.

In one embodiment, the sensors and controller are accommodated within an enclosure. The enclosure is shaped to receive the distribution valve. The distribution valve monitor may include a user interface having a display to enable recorded data and/or distribution valve operation data to be visually presented. The controller compares recorded data with desired distribution valve operating data to detect improper distribution valve operation. The desired distribution valve operating data may be programmable. The distribution valve monitor may further comprise an interface to enable recorded distribution valve operation data to be downloaded to a remote location.

According to another aspect there is provided a distribution valve monitor to monitor the operation of a distribution valve of the type having at least one inlet, a plurality of outlets and a valve mechanism coupling the outlets to the inlet in succession in response to changes in inlet fluid pressure. A distribution valve monitor includes a plurality of sensors disposed at spaced locations about the distribution valve sensing different valve operating conditions. A controller communicates with the sensors and processes sensor output to detect operation of the distribution valve deviating from desired distribution valve operation.

According to yet another aspect there is provided a distribution valve comprising an inlet receiving fluid from a fluid source, a plurality of outlets to deliver fluid to be distributed, a valve mechanism actuable to connect the outlet to the inlet in a desired sequence and a monitor monitoring operation of the valve mechanism and generating an alarm signal when the valve mechanism malfunctions.

In one embodiment, the monitor generates the alarm signal upon jamming or skipping of the valve mechanism. The valve mechanism includes a plurality of spaced magnets thereon. The monitor detects the presence/absence of the magnets to determine the operation of the valve mechanism.

The distribution valve monitor provides advantages in that operation of the distribution valve is recorded and stored. An alarm signal may be generated when the distribution valve fails or malfunctions allowing distribution valve failure to be determined without having to manually cycle the inlet fluid pressure to the distribution valve and visually monitor the distribution valve output. The distribution valve monitor is also easily installed on existing distribution valves without requiring significant modification of the distribution valve.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment will now be described more fully with reference to the accompanying drawings in which:

FIG. 1 is a schematic view of a conventional fluid distribution system incorporating a mechanical liquid distribution valve (MLDV);

FIG. 2 is a side view of the MLDV and a distribution valve monitor in an unassembled condition;

FIG. 3 is a perspective view of the distribution valve monitor;

FIG. 4 is a schematic block diagram of the distribution valve monitor;

FIG. 5 is a side sectional view of the MLDV and distribution valve monitor in an assembled condition; and

FIG. 6 is a cross-sectional view of FIG. 5.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Turning now to FIGS. 2 and 3, the mechanical liquid distribution valve (MLDV) 10 and a distribution valve monitor 50 are shown in an unassembled condition. Distribution valve monitor 50 monitors the operation of the MLDV 10 so that failure or improper operation of the MLDV 10 can be recorded and used to signal an alarm condition depending on the severity of the MLDV operating state.

The distribution valve monitor 50 comprises a sealed enclosure 52 including three compartments, namely a battery and access compartment 54, an electronics and plunger sensor compartment 56 and a rotation sensor compartment 58. The rotation sensor compartment 58 is generally tubular and is sized to accommodate the MLDV 10 so that the rotation sensor compartment 58, for the most part, surrounds the MLDV 10 with the electronics and plunger compartment 56 sitting on top of the MLDV 10. A liquid crystal display (LCD) 60 and a user actuable keypad 62 are provided on the top surface of the electronics and plunger sensor compartment 56 making the LCD 60 and keypad 62 readily available to a user.

FIG. 4 is a schematic diagram of the internal components of the distribution valve monitor 50. As can be seen, the distribution valve monitor includes a low power microcontroller 70 coupled to the LCD 60, the keypad 62 and a programming and interfacing connector 72. Programming and interfacing connector 72 is physically located within the battery and access compartment 54 and is accessible through removal of the lid 54a of the battery and access compartment 54. A replaceable battery 74 is also accommodated by the battery and access compartment 54 and provides operating power to the internal components. Alternatively, the operating power may be provided via the programming and interfacing connector 72 through an isolation switch 76. Microcontroller 70 samples the output of a plurality of hall effect sensors, namely a plunger sensor 80 and rotation sensors 82 to 88. The sampled sensor output is processed by the microcontroller 70 and used to provide output to an alarm relay 90 if an alarm condition exists. Alarm relay 90 is coupled to a dry contact 92 disposed within battery and access compartment 54 via an isolation barrier 94. Dry contact 92 is electrically connected to an alarm panel (not shown) through a copper or fibre-optic link.

The microcontroller 70 and plunger sensor 80 are physically located within the electronics and plunger sensor compartment 56 with the plunger sensor 80 being disposed directly over the plunger 30 of the MLDV 10 (see FIGS. 6 and 7). The rotation sensors 82 to 88 are physically located within the rotation sensor compartment 58 and are disposed about the compartment at generally equal circumferencially spaced locations. The rotation sensors 82 to 88 lie in a plane that corresponds generally to the plane of the plate 32 of the MLDV 10.

FIGS. 5 and 6 best illustrate the positions of the plunger sensor 80 and the rotation sensors 82 to 88 relative to the plunger 30 and plate 32 of the MLDV 10. In order to allow the plunger sensor 80 and rotation sensors 82 to 88 to detect the operational status of the MLDV 10, a magnet 100 is provided at the top of the plunger 30 and a magnet 102 is provided on the plate 32 in line with the aperture in the plate 32. As will be appreciated, when the plunger 30 moves upwardly within the MLDV 10 and brings the magnet 100 in close proximity to the plunger sensor 80, the plunger sensor 80 generates a logic high output. When the plunger 30 is biased downwardly, the output of the plunger sensor 80 returns to a logic low level. When the plate 32 rotates to bring the magnet 102 in close proximity to one of the rotation sensors 82 to 88, that rotation sensor generates a logic high output with the output of the remaining rotation sensors remaining at a logic low level. The microcontroller 70 samples the plunger and rotation sensor outputs thereby to collect actual MLDV operational data.

The microcontroller 70 includes non-volatile memory (not shown) so that data stored therein remains intact even in low and no power conditions. The non-volatile memory is programmed with desired MLDV operating data. The desired MLDV operating data is compared with actual MLDV operating data so that MLDV failure and/or malfunction can be detected. In particular, the operating data is examined to detect MLDV positioning, sequencing and/or timing errors. Data representing the elapsed time the MLDV 10 spends at each outlet position and all detected operational errors and malfunctions are also stored in the non-volatile memory thereby to keep historical data concerning the operation of the MLDV 10.

The operation of the distribution valve monitor 50 will now be described. As mentioned previously, in normal operation of the MLDV 10, fluid pressure supplied to the inlet 12 of the MLDV 10 is cycled according to a desired fluid distribution sequence. Each time the fluid pressure supplied to the inlet 12 drops and then increases, the plunger 30 and plate 32 reciprocate from a down position to an upwardly extended position before returning to the down position. During movement of the plunger 30 and plate 32 up and then back down, the plunger 30 and plate 32 rotate thereby to bring the aperture therein into alignment with a different outlet 24 of the MLDV 10.

Each time the plunger 30 nears the top of its stroke, the magnetic field generated by the magnet 100 causes the plunger sensor 80 to output a logic high. The logic high condition is sampled by the microcontroller 70 and stored allowing the microcontroller 70 to record the duration the plunger 30 remains at the top of its stroke as well as the elapsed time between each plunger reciprocation.

As the plate 32 rotates to bring the aperture therein into alignment with a different outlet 24, the magnet 102 is brought into proximity with the rotation sensor associated with that outlet. The magnetic field generated by the magnet 102 causes the rotation sensor to output a logic high. The logic high condition is sampled by the microcontroller 70 and stored allowing the microcontroller 70 to record the duration the plate 32 remains in that position and hence the duration the inlet 12 is coupled to that particular output.

The average time the MLDV 10 spends at each outlet is calculated. If deviations in average time exist that are above a threshold level signifying failure and/or improper operation of the MLDV 10, an alarm signal is generated. By measuring the elapsed time between strokes of the plunger 30 and the duration the plate 32 remains at each outlet position, the MLDV 10 can be monitored to ensure it cycles properly and is not jammed or skipping. Also by measuring the duration the plate 32 spends at each outlet position, the MLDV can be monitored to ensure fluid is being distributed evenly to each outlet 24. Measuring the duration the plunger 30 remains at the top of its stroke allows sticking plunger conditions to be detected.

When MLDV jamming or skipping conditions are detected by the microcontroller 70, the microcontroller generates an alarm signal causing the alarm relay 90 to close thereby to provide the alarm signal to the alarm panel via the dry contact 92. Plunger sticking conditions and deviations in the duration of the plate 32 at each outlet position are recorded until the situations become severe at which time the microcontroller 70 generates an alarm signal.

When the microcontroller 70 is not receiving input from the plunger sensor 80 and rotation sensors 82 to 88, the microcontroller 70 is conditioned to a â€œsleepâ€ mode to conserve power. The microcontroller however switches to a â€œwakeâ€ mode either in response to activation of one or more keys on the keypad 62 or a change in input received from one of the plunger and rotation sensors.

The LCD 60 and keypad 62 provide a user interface that allows a user to determine and view the operational status of the MLDV as well as recorded data. In particular, through use of the keypad 62, the LCD 60 can be conditioned to display the current operational status of the MLDV i.e. OK or Error, the status of the plunger sensor 80 and rotation sensors 82 to 88, the position of the plate 32, a menu of logged MLDV failures/malfunctions and suggested causes as well as associated times and dates.

The programming and interfacing connector 72 allows a reading device to be coupled to the microcontroller 70 through an interface connector so that stored data can be read and downloaded. The interface connector also allows a device to be coupled to the microcontroller 70 so that the desired MLDV operating data can be updated.

The four (4) outlet MLDV is shown for illustrative purposes only. As will be appreciated, the distribution valve monitor can of course be used with MLDVs including fewer or more outlets. Although hall effect sensors in conjunction with magnets are used to sense movement of the plunger and plate, other non-contact sensing arrangements can of course be used.

The distribution valve monitor as illustrated is installed over an existing MLDV with the MLDV being modified to include the magnets 100 and 102. If desired, the distribution valve monitor and MLDV can be integrated into a single unit to yield a distribution valve that monitors and records its operating status and generates an alarm signal in the event of failure and/or malfunction.

If desired, rather than using a physical connection between the dry contact 92 and the alarm panel and a physical connector 72 in the battery and access compartment 54, the distribution valve monitor may include one or more wireless transceivers to transmit alarm signals to the alarm panel and/or to transmit recorded MLDV operating and error/malfunction data to a remote station and to receive desired MLDV operating data updates from the remote station.

Although preferred embodiments have been described, those of skill in the art will appreciate that variations and modifications may be made without departing from the spirit and scope thereof as defined by the appended claims.