WO2015019128A1

WO2015019128A1 - Device for aiding the detection of low fluid low rates

Info

Publication number: WO2015019128A1
Application number: PCT/IB2013/056513
Authority: WO
Inventors: Martino CONVERTINI
Original assignee: Convertini Martino
Priority date: 2013-08-09
Filing date: 2013-08-09
Publication date: 2015-02-12

Abstract

A device that, exploiting the interaction between magnets with opposite and equal polarity, inserted in any point of a pressurized pipe, before or after a meter of fluid, liquids, gases or vapours, is able to detect, signal and meter flows of liquids, gases and vapours impossible to be measured otherwise, with lower flow rates than the sensitivity limits of the meters, and able to detect leakages, pressure and flow rates.

Description

DEVICE FOR AIDING THE DETECTION OF LOW FLUID LOW RATES

Description of the prior art

Different meters for fluids, liquids, gases and vapours exist which differ from each other in compliance with different technical characteristics and applications: single- jet meters, multiple jet meters, tangential meters, Woitmann meters, membrane meters, turbine meters, electronic meters and others less common.

Most of these types of meters, apart from their construction differences and from some technical details, work by virtue of the same principle: liquid, gas or vapour flows pass through the body of the meter, transferring their speed to the rotation of a turbine or of a propeller, whose rotation allows to detect the liquid, gas or vapour flow rate, and thus to determine its consumption, exhaustive but not limitative example.

In other cases, the measurement is performed by exploiting different principles, such as ultrasound, electromagnetic field, ecc.

Every meter has a lower flow rate limit, which may vary on each model as a function of its class, its size and its quality. In practice, for very low flow rates there is no possibility of detection below a certain value of flow per hour, in order to be detected, signalled and metered.

Thus in the field of the present invention, low flow rate means a flow rate below the sensitivity threshold of a meter per se known.

In the water distribution networks for civil use, these non-metered consumptions can range from 5 to 10% and beyond, of the overall metered consumptions.

Gas metering has the same detection, signalling and measurement problems. For gases, the missed detection of low flow rates, which can be leakages, may generate health and safety problems and damages due to explosive gases. As an exhaustive but not limitative example.

Summary of the invention

The aim of the present invention is to provide a device that allows the traditional flow meters to meter also low flow rates, namely lower than the respective sensitivity thresholds.

The idea at the basis of the present invention is, in conditions of low flows, to allow the passage of the fluid in an intermittent way, alternating increases of potential energy and subsequent transformation into kinetic energy of the fluid. In other words, the flow is modulated in order to generate a pressure pulse train. This allows to reach sufficient pulse flow rates to activate the turbine of a traditional meter.

The present invention thus comprises a mobile shutter, adapted to open in a sudden way in order to free the fluid contained in the circuit in a pulse way, so that a traditional meter can detect such a small fluid quantity. After that, the shutter closes again, until the pressure of the fluid upstream is such as to determine its further sudden opening.

According to a preferred alternative embodiment of the invention, the device itself is able to measure the flow rate of the fluid passing through it, by measuring the position of the magnet and the amount of time in which the shutter stays open. The present invention is based on the interaction between permanent magnets, more in particular:

the magnet's attraction to ferromagnetic materials, for example ferrous materials, steel, etc., the repulsion of magnets having equal and opposed polarity, namely NN or SS. By exploiting the principles of magnetism, the device that is object of the present invention allows to measure flow rates lower than the sensitivity limits of the meters currently in use, when inserted in a pressurized pipe where fluid, liquids, gas or vapours are present.

The device is preferably equipped with means to signal such flows.

The purposes and advantages of this invention will become clear from the following detailed description of a preferred embodiment (and the relative alternative embodiments) and the drawings that are attached hereto, which are merely exhaustive but not limitative, in which:

The attached claims are an integral part of the present description.

LIST OF THE ATTACHED FIGURES

Figures 1-7 describe the device according to the invention, in an exhaustive but non limitative way.

Fig. 1 in example shows the device in rest position: when there is no flow, the shutter of the valve is closed. Fig. 2 in example shows the device in working position: the shutter of the valve is open.

Fig. 3 in example shows an alternative embodiment of the device, wherein an intermediate permanent magnet 15 and a magnetic sensor 14 were inserted. The device is in working position, the shutter of the valve is open.

Fig. 4 in example shows an alternative embodiment of the device in working position: the shutter of the valve is closed.

Fig. 5 in example shows the grid/filter 6 made of ferromagnetic material with the central hole 17 which guides the front spindle of the shutter 8, to exert the attraction force of the shutter magnet 9, which may vary in a linear way by adjusting the distance between the grid/filter 6 and the magnet of the shutter 9, which occurs by screwing or unscrewing the grid/filter 6 in the thread 18, as it is shown in the drawings of fig. 1-2-3-4-6-7.

Fig. 6 in example shows an alternative embodiment of the device in working position, in place of the intermediate magnet 15, a spring was inserted 19, the shutter of the valve is closed.

Fig. 7 shows an alternative embodiment of the device in working position, in place of the intermediate magnet 15, a spring was inserted 19, the shutter of the valve is open.

DETAILED DESCRIPTION OF AN EMBODIMENT OF THE INVENTION.

Figure 1 shows the cartridge (case) of the device that is object of the present invention. Such cartridge has a tubular shape and is made of plastic or metallic material, preferably paramagnetic or diamagnetic, for example aluminium, copper, brass, etc being non ferromagnetic and having size, material and shape in accordance with the needs of the plant-engineering.

Reference 2 indicates a rubber beat gasket made of a material appropriate to its usage, between the device and the pipe where the device itself is inserted.

Reference 3 indicates a ring made of plastic or metallic material to retain all the components inside the cartridge of the device; reference 4 indicates the sealing gasket between the pipe/duct/tube 13 and the cartridge/case 1.

Reference 5 indicates the front support, reference 6 indicates the grid/filter made of ferromagnetic materials, e.g. ferrous materials, stainless steel, etc. Reference 7 indicates a sealing o-ring of the shutter, reference 8 indicates the front driving spindle, reference 9 indicates the magnet inserted within the movable shutter, reference 10 indicates the rear spindle of the mobile shutter, reference 1 1 indicates the fixed magnet inserted in the rear fixed support, reference 12 indicates the fixed rear support, reference 13 indicates the duct (meter tube), reference 14 indicates the magnetic sensor of the reed or hall effect type, reference N indicates the flow direction of liquid, gases, or vapours, reference A indicates the direction of the magnet polarity, examples of the drawings are exhaustive but non limitative.

DETAILED DESCRIPTION OF THE FUNCTIONING

Figure 1 shows the device in rest condition, when no flow is present, the shutter magnet 9, present in the mobile shutter 16, exerts an attraction force between the grid/filter 6, made of ferromagnetic material 6 and the mobile shutter 6, the fixed magnet 1 exerts a repulsion force towards the shutter magnet 9, producing an effect of a thrust spring, determining the closing of the shutter.

In case there is no presence of flow and the mobile shutter 16 is closed, the upstream/input pressure, present at the input of the device, is equal to the downstream/output pressure at the output of the device.

In case of a leakage, a micro-flow or a flow, the difference between the upstream/input pressure and the downstream/output pressure of the device increases slowly or suddenly, until the upstream pressure reaches, exceeds and overcomes the attraction force exerted by the shutter magnet 9 of the mobile shutter over the grid/filter of ferromagnetic material 6, overcoming also the repulsion force of the thrust spring effect of the fixed magnet 1 1 against the shutter magnet 9.

The mobile shutter 16 moves abruptly backwards in open position as in fig. 2, exhaustive but non limitative example.

The abrupt opening movement of the mobile shutter 16 causes the flow speed to generate a very high instant flow rate which makes the meter run.

When the liquid, gas of vapour flow brings the pressure downstream of the device at the value of the upstream pressure, the repulsion force of the thrust spring effect of the fixed magnet 1 1 pushes the shutter magnet 9, which, by entering in the range of the attraction forces between the shutter magnet 9 of the shutter 16 and the grid/filter 6, brings back the mobile shutter in rest position, by closing again the valve, as in fig. 1 , exhaustive but not limitative example.

The presence of a leakage or of a micro-flow repeats to infinity the previous cycle described above.

The movement of the shutter magnet 9 and its position, present in the mobile shutter 16, creates a variation in the magnetic field which can be detected by magnetic sensors of the reed, hall effect type 14 of by magnetic field readers, thus making it possible to measure the value of a flow, to detect the presence of a flow (delivery), to detect the absence of a flow or a leakage, exhaustive but non limitative example.

The spring effect of the magnet in the device, by interacting with sensor of reed or hall effect type, whose protection is required, can be used not only to measure and to detect flows, but also to detect non metered leakages, to measure the pressure, both in presence and in absence of a flow, to detect the presence or the absence of the pressure, from the manostat, in open loop or closed loop plants, exhaustive but non limitative example.

The signals from the sensors can be sent to an electronic circuit which process them and uses them for various industrial or domestic applications, for alarms or measurements.

Example of alternative embodiment

Fig. 3, fig. 4, fig. 6, fig. 7 show alternative embodiments.

In addition to the elements of the device described in fig. 1 and 2, an intermediate mobile magnet 15 is inserted, having a hollow center, free to slide on the rear spindle of the shutter 10, which supports it, in fig. 6 and in fig. 7, in place of the mobile magnet 15, a spring made of paramagnetic or diamagnetic material 19 is shown. The main reason why the intermediate mobile magnet was inserted is the use in case wherein an extension of the spring effect is needed. As it can be seen in fig. 3 and fig. 4, the magnets 9-11-15 are mounted in a symmetrical way, with SS polarity between the magnet shutter 9 and the intermediate mobile magnet 15 and with NN polarity between the intermediate mobile magnet 15 and the fixed magnet 11. All the three magnets repulse each other. The spring effect produced by the repulsive phenomenon of the magnets 9-11-15 mounted with equal and opposed polarity and the consequent variation of the magnetic field due to the movement and the position of the magnet 9, of the mobile shutter 16 and of the mobile intermediate magnet 15 and to the variations of the flow speed connected with a pressure variation, by interacting with the magnetic sensor of the type reed or hall effect or with the magnetic field reader, can be used to measure the flow per hour, exhaustive but non limitative example.

The mobile magnet 15 creates an extension of the spring effect. The more are the intermediate magnets mounted, the more the spring extends. The force of the spring and the effects of the operating principle of the device, however, do not vary, exhaustive but non limitative example.

It is also possible to insert a spring 19 between the two magnets 9 and 11 , without changing the result that the magnet 15 wanted to obtain (spring effect), exhaustive but non limitative example.

When a flow is present, its variability creates a forward and backward movement of the intermediate magnet, as a directly proportional function of the repulsion force between the three magnets and of the flow speed which, consequently, determines its position. The variation of its position determines the variation of the magnetic field, which can be used for the different applications mentioned above, as an exhaustive but non limitative example.

List of the components:

1. Case of the device

2. Beat gasket

3. Blocking ring of the device

4. Sealing o-ring

5. Front support

6. Grid/filter made of ferromagnetic material

7. O-ring shutter

8. Front spindle shutter

9. Shutter magnet

10. Rear spindle shutter 11. Fixed magnet

12. Rear support

13. Pipe/duct

14. Reed/Hall magnetic sensor

15. Mobile intermediate magnet

16. Mobile shutter

17. Central hole of the front spindle guide Shutter

18. Thread attraction force adjustment

19. Spring

A. Opposed polarity of the magnets

N. Flow direction

A. Direction polarity of the magnets

The main advantages offered by the present invention with respect to similar systems known in the art are:

Reduced size and bulk, since the device can be inserted in a standard pipe/tube/connector of the meters for liquids, gases and vapours, both already working and new to be mounted;

Reduced size in order to be inserted directly in a pipe, by simply sectioning the pipe.

Possibility to insert it directly inside any meter of liquids, gases or vapours, in input or in output, before or after the meter.

Speed of opening and closing the fluid with an ON-OFF mode that allows to increase the efficiency of recovering and measuring the leakages.

Possibility of using it in open or closed circuit plants.

E.g. in heating systems, in cooling systems, etc. by mounting it in the different branches of the manifold, it can determine, in case of leakages, not only a signalling of the leakage, but also the branch where the leakage takes place, exhaustive but non limitative example.

In open or closed circuits, the spring effect of the device, if appropriately adjusted, by interacting with the reed or hall effect sensor can be used as pressure sensor. The operating principle of the device determines automatically and simultaneously also the use of the device itself as a check valve (the fluid flows in a single direction), in case the pressure downstream of the device exceeds the one upstream of the device itself, and prevents any unwanted reflux.

Reduction of calcareous deposits within the pipe, thanks to the effect of the permanent magnetic fields, with magnets mounted with opposed and equal poles, on the minerals present in the liquid or gaseous fluids, especially in water, in particular on the carbonate component.

Absence of mechanical inconveniences that, during the operation can cause reliability and duration problems, due to the loss of the adjustment of the spring or to wear or corrosion with consequent prejudice to the effectiveness, since permanent magnets are used. Possibility to detect the presence of a flow, possibility to detect the absence of a flow, possibility to detect a leakage, possibility to measure a flow, possibility to use it as a manostat.

Claims

1. Device for aiding the detection of low fluid flow rates, namely a flow rate lower than a detectability threshold of a meter, the device comprising

a. a cartridge/case (1 ) having a tubular shape adapted to be inserted in a circuit for distributing a fluid

b. a filtering plate (6) made of ferromagnetic material,

c. a mobile shutter (16) mobile between a position of full closing in contact with said filtering plate and a position of full opening, d. the shutter comprising at least a magnet (9), arranged in order to be in contact with said filtering plate (6) when the shutter is in closing position.

2. Device according to claim 1 , further comprising a fixed magnet (11 ) arranged in the container (1) substantially in correspondence of the full opening position of the shutter ( 6) with an orientation of the poles such as to exert a repulsion force against the closing of the shutter.

3. Device according to claim 1 , comprising a pipe/connection (13) inside the cartridge (1), a sealing o-ring (4), between the cartridge (1 ) and the pipe (13), a front support (5) which blocks the plate of ferromagnetic material (6) having an axially adjustable position with respect to the cartridge (1 ).

4. Device according to claim 3, wherein said adjustable position is obtained by screwing/unscrewing the filtering plate in an appropriate thread ( 8) made inside the front support (5).

5. Device according to one of the claims from 2 to 4, further comprising a mobile intermediate magnet (15) arranged between the shutter (18) and the fixed magnet (1 ) with an orientation of the poles such as to exert a repulsion force both towards the shutter and towards the fixed magnet (11 ).

6. Device according to any one of the preceding claims, further comprising a spring (19) placed between said shutter (18) and said fixed magnet (1 ).

7. Device according to any one of the preceding claims, wherein said shutter comprises a first spindle (8) and said filtering plate (6) comprises a corresponding central hole (17) adapted to guide the first spindle (8) according to an axial movement of the shutter with respect to the container (1 )-

8. Device according to any one of the preceding claims from 2 to 7, wherein said shutter comprises a second spindle (10) and said fixed magnet (11 ) has an annular shape, adapted to guide the second spindle (10) according to an axial movement of the shutter with respect to the container ( ).

9. Device according to any one of the preceding claims, further comprising a magnetic sensor (14) of the reed or hall effect type, attached externally to the cartridge (1 ) in a position such as to detect a proximity position of the magnet (9) of the shutter corresponding to a position of a full opening of the shutter.

10. Device according to claim 9, further comprising means to measure the opening time of the shutter to convert said time in an overall volume or mass of fluid that passed through the device itself.

11. Device according to claim 9 and 10, further comprising means to measure the position of the shutter and the opening time of the shutter itself to convert said position in an overall volume or mass of fluid that passed through the device itself.

12. Device according to any one of the preceding claims, further comprising sealing means (7) to seal the shutter in closing conditions: the device thus serving as a check valve.

13. Device according to any one of the preceding claims, wherein said cartridge (1 ), said connector (13) and said shutter (8) can be made of plastic, metallic material, preferably of paramagnetic or diamagnetic material such as copper, brass, aluminium, ecc.

14. Usage of the device according to any one of the preceding claims from 1 to 12, arranged upstream or downstream, according to a direction of circulation of the fluid, of a traditional measuring meter, in order to allow the latter to meter lower flow rates than a respective sensitivity threshold.

15. Usage of the device according to any one of the preceding claims from 1 to 14, as a measuring meter of the volume/mass of the fluid that passes through the device, on the basis of the metering of the position of the shutter and of the overall opening time of the shutter.

16. Method for metering a low flow rate of fluid comprising the step of making said flow rate intermittent, in order to generate a pressure pulse train.