GB2592696A

GB2592696A - Fluid monitoring device

Info

Publication number: GB2592696A
Application number: GB2012959.9A
Authority: GB
Inventors: John Pumphrey Trevor
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-08-20
Filing date: 2020-08-19
Publication date: 2021-09-08
Also published as: GB202012959D0; GB201911921D0

Abstract

A fluid monitoring device for inline connection to a flow pipe, the device comprising: · an inlet 103 for flow from an upstream portion 110 of the pipe, · an outlet 105 for flow to a downstream portion 112 of the pipe, · a hollow body 104 and passage 106 between the inlet and the outlet, · a closure valve, spherical ball valve (113, fig 11), for closing the hollow body to flow there-through between the inlet and the outlet, · means for detecting usage and/or high leak flow through the device, flow measuring turbine (121), · a transducer for monitoring the usage and/or high leak flow detecting means, · means for detecting low leak flow through the device, · a transducer for monitoring the low leak flow detecting means and · monitoring circuitry for monitoring the transducers and closing the valve and/or generating an alarm signal in the event of high or low leak flow.

Description

FLUID MONITORING DEVICE

The present invention relates to a fluid monitoring device.

As the population grows, increased strain is exerted on the Earth's natural resources, in particular, a once abundant water supply. As a result, the cost of water has increased and it is now even more important to prevent wastage.

A lot of the water supplied to a property can be lost for several reasons, to including that of human error. However, the most common cause of water wastage is leaking pipes. Leaks can occur in any type of pipe and for many reasons, but usually the leak becomes catastrophic before it is-noticed which can cause irreparable damage to the surrounding areas.

Previous leak detection devices have been able to detect substantial water leaks within a piping system, usually by detecting changes within the flow volume passing through the device during a set time interval and comparing the results to preset parameters. However, this only accounts for severe leaks where there is substantial water loss. In most cases, a crack or other form of damage will have been present for some time before there is a catastrophic leak event, culminating in wasted water and increased water bills.

The object of the present invention is to provide an improved fluid monitoring device.

According to the invention there iS provided a fluid monitoring device for inline connection to a flow pipe, the device comprising: * an inlet for flow from an upstream portion of the pipe, * an outlet for flow to a downstream portion of the pipe, * a hollow body between the inlet and the outlet, * a closure valve for closing the hollow body to flow there-through between the inlet and the outlet, * means for detecting usage and/or high leak flow through the device, * a transducer for monitoring the usage and/or high leak flow detecting means, * means for detecting low leak flow through the device, * a transducer for monitoring the low leak flow detecting means and * monitoring circuitry for monitoring the transducers and closing the valve and/or generating an alarm signal in the event of high or low leak flow.

Preferably: * the closure valve is an electro-mechanical valve; * the usage and/or high leak flow detecting means is an impeller mounted for to flow through it and the transducer for monitoring the usage and/or high leak flow detecting means is arranged to monitor rotation of the impeller; * the usage and/or high leak flow detecting means is mounted at the inlet upstream of the closure valve; * the means for detecting low leak flow through the device is mounted at the outlet downstream of the closure valve; * the means for detecting low leak flow comprises a member arranged to close substantially the device with no flow there-through and displaceable in a flow direction against a return spring to allow usage and/or high leak flow there-through, * the member and the body have a co-operating bore and plug movable out of engagement against the return spring by flow through the device and movable by the return spring into engagement with no flow through the device, * fit between the plug and the bore being such that flow less than the low flow can pass the plug when it is moved back opposite the flow direction and * the transducer for monitoring the low leak flow is arranged to monitor the position of the plug; * the member arranged to substantially close the device has: * a cage slidable in a bore in the body and permitting flow past the cage when the member is displaced against the spring and * a nose slidable in a smaller bore within the body.

* the nose carries a seal co-operating to provide substantial closure with a bore in the body or in a collar within the body, typically a seat of the valve or the nose is plain and co-operates to provide substantial closure with a seal mounted in the body; * the bore in the body or the collar or the nose have a fine groove to provide the flow less than the low flow; * the fine groove is of the order of 0.05trun deep; * the plug incorporates a magnet and the transducer is a reed switch; * the monitoring circuit is adapted to close the valve and/or generate an alarm signal in the event of usage and/or high leak flow being detected to persist for longer than a threshold or flow less than the low flow being detected; * the monitoring circuit is adapted to detect the low flow as persistent displacement of the said member in conjunction with no usage and/or high leak flow through the device.

It is preferred that the inlet is tubular in shape, thus simplifying connection to standard pipework. However, it is conceivable that the inlet could be of any regular shape with an adaptor for connection to any fluid system.

The inlet and outlet are preferably threaded for direct, in line attachment to the pipework in question. Alternatively, they could be of a reduced diameter to fit inside the standard pipe, with an external seal applied around it. In much the same way, the inlet and outlet could be of a greater diameter than the pipework, with an external seal enclosed there around.

It is preferred that the turbine will rotate in response of the flow through the inlet of the device. In this instance, a proximity sensor would detect the angular stroke rotation of the turbine blades, which generates a measurable frequency that would be proportional to the flow rate of the fluid. It is conceivable that that the rate of flow could be monitored using a magnetic flow meter whereby a magnet would be held within the bore of the outlet, and the second magnet with opposing polarity would be in the casing. The resistance to the flow of the fluid caused by the attracting magnets would be detected by a hall-effect transducer and would convert the movement into a measurable voltage. Other flow sensors that could be used include orifice plate sensors, venturi or nozzle sensors.

Possibly, the valve could be any suitable stop valve, such as an isolating valve, $ a lever ball valve or a stopcock. Preferably, the valve will be a ball valve. It is typical that the position of the valve (and thus the flow of the fluid passing through it) can be manually controlled by a user from the outside, via a dial, lever or handle. Alternatively, it is preferred that the position of the valve can be controlled remotely using a mobile device or tablet. However, it is preferred that that the position of the valve is controlled through programming on a central display.

The device could possibly be run from the mains supply of a dwelling, such as a 13A plug into a 230V UK mains supply. In the alternative, the device could be run remotely using a battery power supply or individual batteries. However, it is preferred that the device is run from the mains supply using a mains adaptor, reducing the input voltage to 5V.

Typically, the piston will be a of circular cross-section that is of substantially equal diameter to that of the inlet bore, with a cylindrical body extending into the outlet. Nonetheless, it is envisaged that the piston could be of any shape so long as it conforms to the internal shape of the inlet pipe such that it is able to move in response to fluid flow therethrough.

Whilst it is possible that the body of the piston is solid around its circumference, it is preferable that the piston body is cage-like, having a number of individual struts with a shoulder to seal the entrance to the outlet. The face of the shoulder preferably has a solid, integral disc to block a flow through the pipe during non-flow events. Upon commencement of a low flow event, the fluid acts against the disc, pushing the piston backwards into an area of the outlet having a wider bore, and allowing flow around it. In this way, the cage-like body provides the piston with minimum and maximum points of movement in the outlet.

Whilst it is possible that the piston is of any lightweight material, such as polyethylene terephthalate (PET) or high-density polyethylene (HDPE), it is preferably of polyoxymethylene (POM).

It is preferred that the cage-like body of the piston will have a shielded groove on the struts for location of the magnet to prevent water damage in use. However, it is conceivable that there is a bespoke casing inside the piston for magnet location. Alternatively, the piston could be a hollow cylinder with a closed rear end, in which the magnet would be housed.

It is imagined that there could be more than one magnet held on the piston, for example, one on a top strut and one on a bottom strut.

Preferably, the movement of the piston is preferably detected using a reed switch, though it is conceivable that it is detected using a hall-effect sensor.

It is possible that the spring is replaced by a magnet whereby the piston has a magnet located upon it with one polarity, and the entrance to the outlet has the other polarity, thus ensuring the return of the piston after a leak event. It is preferred however, that the spring be a helical compression spring that sits behind the piston. It is possible that the spring could also be a conical or disc spring. In the alternative, it is conceivable that the spring is an extension spring, one end connected to the front face of the piston and the other connected to the entrance to the outlet.

It is envisaged that the device be connectable to external software that can be installed into building security equipment. Alternatively, the device can be equipped with Bluetooth 0 and/or wi-fl, such that it can be remotely connected and controlled by a user, for instance, such that a homeowner may be able to amend pre-set parameters. The fundamental flow parameters to be measured being that of volume and duration.

Passing a certain minimum and/or maximum threshold will cause an alarm event whereby a light could flash and/or an audible alarm would sound in the manner of a siren. Importantly, upon detection of an alarm-able event, the valve will shut off automatically.

Possibly, the alarm could be either visual or audible, though it is preferably 5 both. In the embodiment where there is Bluetooth 0 ancUor wi-fl, it is preferred that the alarm is raised on a user's mobile phone in the first instance.

It is possible that the monitoring parameters are computer generated, the input being directly inserted into the device circuitry. It is preferred however, that the user is at least able to amend the parameters in order to allow for bespoke monitoring of a dwelling, such that a user has the option to for the device to reflect their personal circumstances i.e. a holiday period whereby the property will be vacant.

To help understanding of the invention one embodiment and a variant thereof 15 will now be described by way of example and with reference to the accompanying drawings, in which: Figure 1 is an isometric view of a first fluid monitoring device of the invention; Figure 2 a front face view of the device of Figure 1; Figure 3 an exploded view of the device of Figure 1; Figure 4 is a side view of the device of Figure 1; Figure 5 is a right-hand end view of the device of Figure 1 showing its inlet; Figure 6 is a left-hand view of the device of Figure 1 showing the outlet; Figure 7 is an oblique cross-sectional view on the centre line of a flow passage 25 through the device of Figure 1; Figure 8 is an another cross-sectional view through a front portion of housing of the device; Figure 9 is a front cross-sectional view on the same plane as Figure 7 of a variant of the device of Figure 1; Figure 10 is a view similar to Figure 9 at an oblique angle; Figure 11 is an enlargement of the inlet end of the device of Figure 9; Figure 12 is a similar enlargement of the outlet end of the device of Figure 9; Figure 13 is a perspective view of a turbine stator of the device of Figure 9; Figure 14 is a similar perspective view of a cage and piston member of the device of Figure 9; Figure 15 is an oblique transverse cross-sectional view of a body of the device of Figure 9 at a position of the cage and piston member and Figure 16 is a perspective view of the variant of Figures 9 to 15 with a front case member removed to show the position of transducers.

Referring to the Figures, there is a fluid control device 1 that can be connected in line to various types of pipe, typically domestic water pipes. The device runs twenty-four hours a day, taking continuous volume and flow-duration measurements. The device provides a user with the ability to control the supply of water to a property and detect any leaks before they become catastrophic, whilst also automatically shutting off the water supply should an alarm event be detected.

The device has a central housing 2, divided into three parts; front 3, middle 4 and rear 5. The front part 3 has a visible display 6 on its outwards face. The display is LED and illuminates once it is turned on..The display is located on a rotational plate 7 so that the display can be upright (or any comfortable angle for the user), in any condition. Buttons 8 on the plate allow for the device to be manually programmed by a user.

A threaded inlet 9 on the device allows it to be directly connected into the pipe in question. Inside of the inlet, there is a magnetic turbine 10 with blades housed within a fast and second turbine casing 11, 12 respectively. The turbine is connected to the casings by a rod 13, such that the turbine can easily rotate about it. The second casing sits flush against the inside surface of the inlet to prevent any unwanted movement during flow.

The movement of the blades is measured by a hall-effect sensor 14, which is 30 held upon a printed circuit board (PCB) 15 by a mount 16.

The middle and upper parts of the housing 4 and 5, are screwed together to allow enough space for an electric motor 17. The motor itself is connected to the PCB 15 in the middle of the housing.

A brass casing 18 is located at the junction between the inlet and the outlet, 9 and 19 respectively, connecting them together. Within this casing there is a ball valve 20. As standard, in one position, the ball valve allows fluid flow through it, in another position, fluid flow is prevented. At the various incremental positions, the rate of flow of the fluid can be increased or decreased.

A spindle 21 attached to the top face of the valve and the other to the motor, via an indicator 22. In this way, the valve can rotate into position around its vertical axis.

At either end of the brass casing, there is a seal 23 for preventing seepage between the inlet or outlet and the brass body during use.

Is Inside the outlet there is a piston 24, which has a cage-like body 25 with longitudinally extending struts 26. At the front of the piston, there is a shoulder 27 with an 0-ring 28 extending around its circumference. The 0-ring and the shoulder are held in abutment with a circumferential groove (not shown) in the outlet pipe. This acts as an automatic back flow eliminator in use.

The front face of the piston shoulder is a solid disc 29 of 20mm diameter and sits centrally in the bore of the brass body. As water flows, it pushes against the piston disc 29, causing the whole piston to move backwards from its "sealed" position into a part of the outlet with a wider bore. The fluid is thus able to flow around the piston.

The piston is made of polyoxymethylene (POM) so that it does not unduly contribute to the weight of the device.

Abutting the rear surface of the piston is a helical compression spring 30 that 30 acts against the piston to keep it in abutment with a circumferential lip 31 on the inside of the cage 25, forming the seal. The spring also acts to return the piston to its usual position once water flow has ceased and the device needs to be reset.

On a top strut of the piston, there is a shielded groove 32 for a magnet 33 and an insert 34 to be located behind it. In this way, the insert prevents any water ingress into the groove that would damage the magnet.

When there is flow, the piston disengages from the lip 31, which distances the magnet from a normally open reed switch 35. The absence of the magnetic field causes the reed switch to close, thus completing the circuit and allowing electricity to flow. In this way, the duration of the water flow can be measured.

When flow stops, the spring forces the piston and magnet back into their resting positions. The magnetic field is generated again, and the reed switch opens, breaking the electrical circuit and stopping the measurement of the leak event. In effect, the device is "reset".

Another magnet 36 is located below the indicator 22, under the PCB for detecting larger flow events by means of the turbine rotation.

As there are two means of flow detection within the device (the turbine and the piston), both high and low flow events can be detected. The user monitors two parameters; the volume of water allowed to pass through the valve during a period, and the duration of said flow allowed. In this way, the volume of the water can be controlled, as well as how long the water is supplied to the property.

The device can also detect leaks within the pipe framework. Typically, a leak is detected using water displacement, in that whereby any loss of water resulting from a potential leak is detected mechanically when the ball valve is re-opened due to the physical movement of the piston within water-flow. This test can be conducted manually or on a schedule dictated by the user and operates in addition to the normal and continuous low flow monitoring initially described.

Alternatively, the device is capable of being used with acoustic measurement instruments such that the flow in the pipes can be "listened to". A higher frequency of acoustic signal indicates fluid exiting through a leak at high pressures. These signals are detected over a period and stored within an internal device memory (not shown). I0

All new signals are recorded and compared to previous results. Abnormal results (or those outside of a pre-defined range) will signal an alarm event.

A 1.JSB cable 37 extends from the PCB and allows for powering of the device 5 from the mains supply. It can further act as a means for the flow information to be manually downloaded onto an external drive or to connect with other monitoring devices.

Referring to Figures 9 to 15, a modified fluid monitoring device 101 is now io described. It has a three part brass body 102, with an inlet part 103, a mid-part 104 and an outlet part 105. They define a hollow passage 106 through the body and the device. They are threadedly joined with 0-rings 108. The inlet part provides an inlet 107 to the device and threadedly receives a gland nut 109 for an inlet pipe run 110 for water to flow through the unit. Similarly the outlet part has another gland nut 111 for an outlet pipe run 112. The gland nuts and glands can be of standard plumbing fining type.

The mid-part houses a spherical valve ball 113 with a through bore 114 and a seat 115 for the ball received at a step 116. The inlet part has a complementary seat 117 on its step. The seats are held at a spacing to allow the ball to turn yet seal when closed by abutment of a flange 118 on the inlet part with an end face 119 of the mid-part.

The inlet part has a spider 120 to limit insertion of the inlet pipe and form an abutment for a flow measuring turbine 121 inserted from inner end of the inlet part. It comprises a two inter-engaging fixed parts 122,123, held between the spider and seat of the ball seal 117, and a rotor 124. The outer fixed part 122 has a set of stator blades 125 with a central boss 126 housing a stainless thrust ball 127 and the end of a stainless shaft 128 for the rotor. The other part 123 has a similar, though straight spider 129 and bore 130 for a ball 131 at the other end of the shaft. The rotor has planar blades 132 turned by the twist impart to water flow through the stator. The rotor is moulded with magnetic polymer tips, allowing a Hall Effect sensor 133 positioned against the outside of the inlet part of the body to detect rotation of the rotor and hence measure flow through the device.

II

The arrangement downstream of the ball valve is a little more complex. The mid-part of body steps out in diameter behind the step 115 to a parallel bore 134 closed by the outlet part. At the step, the bore receives a lip seal 135 retained by a clip 136 in a groove 137 in the bore. The lip of the seal is directed towards the valve ball. An acetyl moulded member 140 is received in the bore 134. It has a back end formed as a cage 141 with axial ribs 142 and a back ring 143. Also it has a front nose 144 of a diameter to fit within and seal with the lip of the seal. The end 145 of the nose is dished complementarily with the curvature of ball 113, to allow a distinct length 146 of the nose to be within the lip seal, when the member 140 is urged towards the ball by a spring 147 seated within the outlet part 105 at an outlet spider 148.

It will be appreciated that with the lip seal making good sealing contact with the nose, the spring will not normally be able to move the member forward. Either or both of drawing a vacuum in the downstream portion of the pipe run or overcoming the upstream pressure in the pipe run preclude the spring from being able to move the member to its normal position with a rim 149 seated against the rigid ring 150 of the lip seal. To allow the pressure on opposile sides of the seal to equalise, all be it slowly, a shallow groove 151, of the order of 0.05mm deep, is moulded in the groove. The groove allows only very low flow past the seal.

In use, with the valve ball open, when a tap or appliance in plumbing downstream of the device draws water, there is significant pressure from the upstream supply to displace the cage and nose member out of the seal. Since its diameter 152 at the rim 149 is less than the parallel bore 143, water can flow round the rim, through the cage with the pressure difference across the nose holding the spring 147 compressed. The flow volume is detected by the turbine and Hall Effect sensor 133. When the tap is closed, the pressure across the nose equalises save for the urging of the spring 147. This slowly returns the nose with flow along the shallow groove until the rim 149 abuts the ring 150 of the seal.

In the event of a major leak in the plumbing, normally with at least as large a flow as that of an open tap, it will not stop unless noticed by a householder for instance. Closure of the ball valve will be described below.

In the event of a minor leak such as a dripping tap, the flow will be greater than that possible along the shallow groove and the nose will move out of, or at least as far as, the lip of the seal and stay there indefinitely. This position for the cage/nose member is detected by means of one 155 of the ribs of the cage being bigger than the others. It sealingly receives a magnet 156 and has an external nib 157. The bore 134 has a complementary longitudinal groove 158. At a position where the magnet would normally be inside of, a reed switch 159 is positioned externally of the body. It is held closed by the magnet and opens in the event of flow, either tap/major leak flow or minor leak.

The body is housed in a rear compartment 161 of a moulded plastics material casing 162. In a front compartment is a PCB 163, with a display 164 in a front face 165 of the casing. The display and controls 166 are mounted in circular piece set in a circular aperture in the housing, whereby the display can be turn to suit the installation orientation of the device. The Hall Effect sensor 133 and the reed switch 159 are mounted on, or at least connected to, the PCB. Also connected to it is actuator for driving the valve ball between its open and closed positions.

Normally the device will be programmed to close the valve if the detected flow volume exceeds a maximum threshold and/or if a lower threshold is exceeded for a specified time period or indeed if the low flow is continuous. All of these conditions are indicative of a leak in the plumbing downstream of the device.

These thresholds of flow are widely different. Typically the maximum threshold will be of the order of 2 litres per minute, whereas the low threshold will 30 be of the order of 2 litres per hour.

To use the unit effectively the customer specifies a maximum time for any flow (say 60 minutes) and a maximum volume (say 100 litres) and when either of those parameters are met the unit shuts off the supply. As soon as any flow of water stops, the pressure on the inlet and outlet sides of the valve balance and then the piston is able to be pushed to the home position by the internal spring. Without the bleed feature on the piston the hydraulic effect of the water would prevent the piston returning home through the seal, and thereof the reed switch would remain activated.

Once the piston returns home the internal time and volume counters are reset in readiness for the next flow of water.

The invention is not intended to be restricted to the details of the above described embodiment. For instance, the device can be connected to the Bluetooth 0 10 of a user's smartphone for remote control therefrom.

The device can also "self-learn" from previous flow events and flow results. This provides a user with the ability to easily set parameters based on similar historical circumstances.

Claims

CLAIMS: I. A fluid monitoring device for inline connection to a flow pipe, the device comprising: * an inlet for flow from an upstream portion of the pipe, * an outlet for flow to a downstream portion of the pipe, * a hollow body between the inlet and the outlet, * a closure valve for closing the hollow body to flow there-through between the inlet and the outlet, * means for detecting usage and/or high leak flow through the device, * a transducer for monitoring the usage and/or high leak flow detecting means, * means for detecting low leak flow through the device, * a transducer for monitoring the low leak flow detecting means and * monitoring circuitry for monitoring the transducers and closing the valve and/or generating an alarm signal in the event of high or low leak flow.
2. A fluid monitoring device as claimed in claim 1, wherein the closure valve is an electro-mechanical valve.
3. A fluid monitoring device as claimed in claim 1 or claim 2, wherein the usage and/or high leak flow detecting means is an impeller mounted for flow through it and the transducer for monitoring the usage and/or high leak flow detecting means is 20 arranged to monitor rotation of the impeller.
4. A fluid monitoring device as claimed in claim 1, claim 2 or claim 3, wherein the usage and/or high leak flow detecting means is mounted at the inlet upstream of the closure valve.
5. A fluid monitoring device as claimed in claim 1, claim 2, claim 3, or claim 4 25 wherein the means for detecting low leak flow through the device is mounted at the outlet downstream of the closure valve.
6. A fluid monitoring device as claimed in any preceding claim, wherein: * the means for detecting low leak flow comprises a member arranged to close substantially the device with no flow there-through and displaceable in a flow direction against a return spring to allow usage and/or high leak flow there-through, * the member and the body have a co-operating bore and plug movable out of engagement against the return spring by flow through the device and movable by the return spring into engagement with no flow through the device, * fit between the plug and the bore being such that flow less than the low flow can pass the plug when it is moved back opposite the flow direction and * the transducer for monitoring the low leak flow is arranged to monitor the position of the plug.
7. A fluid monitoring device as claimed in claim 6, wherein the member arranged to substantially close the device has: * a cage slidable in a bore in the body and permitting flow past the cage when the member is displaced against the spring and * a nose slidable in a smaller bore within the body.
8. A fluid monitoring device as claimed in claim 7, wherein the nose carries a seal co-operating to provide substantial closure with a bore in the body or in a collar within the body, typically a seat of the valve.
9. A fluid monitoring device as claimed in claim 7, wherein the nose is plain and cooperates to provide substantial closure withia seal mounted in the body.
10. A fluid monitoring device as claimed in claim 8 or claim 9, wherein the bore in the body or the collar or the nose have a fine groove to provide the flow less than the 20 low flow.
11. A fluid monitoring device as claimed in claim 10, wherein the fine groove is of the order of 0.05mm deep.
12. A fluid monitoring device as claimed in any one of claims 610 11, wherein the plug incorporates a magnet and the transducer is a reed switch.
13. A fluid monitoring device as claimed in any preceding claim, wherein the monitoring circuit is adapted to close the valve and/or generate an alarm signal in the event of usage and/or high leak flow being detected to persist for longer than a threshold or flow less than the low flow being detected.
14. A fluid monitoring device as claimed in any preceding claim, wherein the monitoring circuit is adapted to detect the low flow as persistent displacement of the said member in conjunction with no usage and/or high leak flow through the device.