Device for detecting the liquid level in a well / tank and electric immersion pump having the same

Abstract

The present application relates to a device for detecting the liquid level of a well / tank and an electric immersion pump provided with the device. A device (10) for detecting the liquid level of a well / tank, comprising: - a management and control element (40) of electronic type, - a first part (12) comprising an air pressure sensor, which is physically / electrically connected to the management and control element (40), - a second part (13) comprising a pressure transducer (15) and which is connected to the management and control element (40) by a wireless connection.

Description

[0001] The present invention relates to an apparatus for detecting the liquid level in a well / tank.

[0002] The invention is particularly suitable for detecting the liquid level in a well / tank in which an electric immersion pump is used.

[0003] The invention also relates to an electric pump provided with such a device.

[0004] An electric submersible pump is an electric pump used inside wells and / or tanks to extract the liquid (usually water) contained therein.

[0005] One of the most strongly felt needs on the part of users is to know the level of the liquid in the well / tank and therefore its remaining availability.

[0006] Currently, in order to know the liquid level of a well / tank, the user must, for example, insert his head in order to have direct visual contact with the free surface of the contained liquid.

[0007] In the present description, the expression "free surface" is understood to mean the separation surface between the liquid phase (the liquid contained in the well / tank) and the gas phase (air).

[0008] However, often the well / tank in which the submersible pump is used is not easily or quickly accessible to the user.

[0009] Therefore, liquid level probes including immersion probes are widely used.

[0010] These submersible probes are immersed in the well / tank, usually to the bottom, and measure the fill level or height of the well / tank based on the principle of liquid generation using the relative density of the liquid and the force of gravity, which increases in proportion to the fill level.

[0011] These probes comprise a measuring end containing, for example, silicon strain gauges and electronics for evaluating changes in the silicon strain gauges, from which one or more metal cables with capillaries extend in order to compensate for atmospheric pressure.

[0012] A measurement of the liquid level is provided by determining the difference between the ambient pressure measured by a sensor external to the tank and the pressure measured by the probe.

[0013] As an alternative, for example, a float-type level probe is used.

[0014] These float probes include a magnet inside the float that moves according to the movement of the well / tank level and interacts with one or more reed-type electrical contacts, changing their electrical state.

[0015] However, all these known methods have some disadvantages.

[0016] Firstly, for their operation, these probes have at least one cable that must be connected to a dedicated user interface outside the well / tank.

[0017] This requires a considerable space occupation and requires providing a passage for the power supply cable of the electric pump to enter the tank in addition to one passage dedicated to the passage of the cable and one passage for the delivery pipe.

[0018] Furthermore, the user is forced to use both an electric pump and a level probe, and this requires the user to:

[0019] - The disadvantage is that two pieces of equipment must first be purchased (electric pump and probe) and then two different installations must be performed, resulting in an increase in the time required to install the well / tank.

[0020] - Two power supplies need to be provided and used, one for the electric pump and another for the probe, or one power supply with two different outputs needs to be used.

[0021] Furthermore, disadvantages are caused by the fact that the installation of the probe generally has to be performed by a specialist and cannot be easily performed by the user.

[0022] The object of the present invention is to provide a device for detecting the liquid level of a well / tank and an electric pump having such a device which improve the background art in one or more of the aspects indicated above.

[0023] Within this aim, an object of the invention is to provide a device for detecting the liquid level of a well / tank which can be easily installed by the user and at any time.

[0024] Another object of the present invention is to provide a device for detecting the liquid level of a well / tank, which device is at least partially integrated in an electric pump used in said well / tank.

[0025] A further object of the present invention is to provide a device for detecting the liquid level of a well / tank which device has a reduced space occupation.

[0026] Another object of the present invention is to provide a device for detecting the liquid level in a well / tank which does not require dedicated access to the well / tank for its power supply and operation, but rather utilizes the same access to the well / tank as used by an electric pump.

[0027] Another object of the present invention is to provide an electric pump comprising a device for detecting the liquid level of a well / tank, which device enables the above enumerated aims and objectives to be achieved.

[0028] Another object of the present invention is to overcome the disadvantages of the background art in a way that can replace any existing solutions.

[0029] Another object of the present invention is to provide a device for detecting the liquid level of a well / tank and an electric pump having such a device which is highly reliable, relatively easy to provide and of competitive cost.

[0030] This object and these and other aims which will become more apparent hereinafter are achieved by a device for detecting the level of a liquid in a well / tank, characterised in that the device comprises:

[0031] – management and control elements of electronic type,

[0032] - a first part, which comprises an air pressure sensor, which is physically / electrically connected to said management and control element,

[0033] - A second part comprising a pressure transducer and connected to the management and control element by a wireless connection. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Further features and advantages of the invention will become more apparent from the description of a preferred but not exclusive embodiment of a device for detecting the liquid level of a well / tank and of an electric pump having such a device according to the invention, illustrated by way of non-limiting example in the accompanying drawings, in which:

[0035] Figure 1 is a view of a device for detecting the liquid level of a well / tank and an electric pump to which the device is applied according to the present invention;

[0036] Figure 2 yes Figure 1 A partially exploded detail view shown in;

[0037] Figure 3 yes Figure 1 A cross-sectional view of the detail shown in;

[0038] Figure 4 is a cross-sectional view of an electric pump according to the present invention;

[0039] With reference to the drawings, an apparatus for detecting the liquid level in a well / tank according to the present invention is generally indicated by the reference numeral 10 .

[0040] The device 10 is applied to an electric pump 11 and is at least partially integrated in the electric pump 11 .

[0041] The device 10 comprises:

[0042] An element 40 of the electronic type for the management and control of the device 10 , connected and / or coincident with an interface that may coincide with or be connected to the user interface of the electric pump 11 .

[0043] a first part 12 comprising an air pressure sensor physically / electrically connected to a management and control element 40 ,

[0044] - A second part 13 comprising a pressure transducer 15 , the second part 13 being connected to a management and control element 40 via a wireless NFC (Near Field Communication) type connection.

[0045] The air pressure sensor is, for example, a sensor of the type known under the trade name “Infineon DPS310”.

[0046] The pressure transducer is, for example, a transducer of the type known under the trade name "Honeywell MPRLS0025PA00001A".

[0047] The first portion 12 is outside the well / tank.

[0048] The air pressure sensor has a data link to the electric pump 11 via the electrical main 14 .

[0049] In particular, the air pressure sensor has a data link to the management and control element 40 via an electrical connection, using the so-called “power line” technology, also called PLC (“Power Line Communication”).

[0050] The electric pump 11 is of the submerged type, extending vertically in the use configuration and comprising a containment vessel 19 inside which there are:

[0051] - a wet section 16 comprising an inlet section and a delivery section, neither of which is shown in the figures, and one or more impellers 33 keyed to a shaft 34, each impeller having its own diffuser and interposed between the inlet section and the delivery section,

[0052] - an electromechanical part 17 comprising a motor device 35 for moving the shaft 34,

[0053] An electronics part 18 comprising a compartment 20 inside which components 21 for the control and actuation of the electric pump 11 are housed, said components being provided with a circuit board 36 .

[0054] The control and actuation assembly 21 is connected to a user interface and comprises communication means 22 of the NFC type.

[0055] The NFC communication device 22 is constituted by an antenna.

[0056] These communication means 22 are electrically connected to a user interface and / or to management and control elements 40 of the device 10 .

[0057] The second part 13 of the device 10 comprises complementary communication means 23 of the NFC type.

[0058] The electric pump 11 comprises mechanical means for engaging the second part 13 of the device 10 , which comprises corresponding complementary mechanical means.

[0059] In particular, the antenna 22 is arranged near a socket 24 which is inside the electronics portion 18 and accessible from outside the housing 19 , but outside the compartment 20 .

[0060] The socket 24 is suitable for being plugged into the second part 13 of the device 10 , at least at the complementary NFC communication means 23 .

[0061] A complementary NFC communication device 23 is arranged in one end of the second portion 13 .

[0062] By means of NFC communication between antenna 22 of control and actuation unit 21 and complementary communication means 23 of device 10, device 10 can be installed without physically / electrically connecting second part 13 of device 10 to management and control element 40 and / or to a user interface.

[0063] This simultaneously allows the risk of penetration into the compartment 20 to be reduced.

[0064] Furthermore, the user may purchase the electric pump 11 and later decide whether and when to purchase and install the device 10 .

[0065] By means of NFC communication between the antenna 22 of the control and actuation assembly 21 and the complementary communication means 23 of the second part 13 , the user can autonomously and easily mount the device 10 on the electric pump 11 .

[0066] In certain cases, the socket 24 of the electric pump 11 has such a shape and dimensions that it is substantially complementarily shaped with at least the complementary communication device 23, thereby ensuring easy insertion and coupling of the device within the socket.

[0067] The second portion 13 of the device 10 has a generally quadrilateral outline and is generally flat.

[0068] The pressure transducer 15 is laterally adjacent to and electrically connected to the complementary communication means 23 and converts the pressure into an electrical signal which is then sent to the management and control element 40 and / or to a user interface.

[0069] The transducer 15 is an integrated circuit comprising:

[0070] – Piezoresistive element for detecting absolute pressure,

[0071] – electronic circuits for analog conditioning of signals,

[0072] – Digital interface for communication with a microcontroller / microprocessor.

[0073] The device 10 comprises a tube 25 made of a plastic material, such as silicone, which extends from the transducer 15 towards the bottom of the tank.

[0074] In particular, the tube 25 extends along one side of the electric pump 11 inside an adapted conduit 26 having a vertical extension.

[0075] Pipeline 26 is provided by:

[0076] - a first channel 31 , which is anchored to one side of the electric pump 11 ,

[0077] A second covering channel 32 , which is fixed to the first channel 31 in order to provide the duct 26 .

[0078] The tube 25 leads into a substantially bell-shaped element 28 , with which it communicates and which is arranged outside the housing 19 substantially at the wet part 16 of the electric pump 11 .

[0079] The tube 25 contains air, and the specific shape and arrangement of the tube 25 inside the duct 26 and the generally bell-shaped element 28, and the presence of the generally bell-shaped element 28, are such that liquid cannot rise to the transducer 15 even when the electric pump 11 is submerged.

[0080] In this case, the tube 25 is prevented from filling with water and changing the reading of the transducer 15 .

[0081] The electric pump 11 is in fact vertically immersed and during this step, air is present inside the substantially bell-shaped element 28 and, due to the shape of said element, it cannot escape, remaining trapped inside the assembly constituted by:

[0082] - a substantially bell-shaped element 28,

[0083] – Tube 25.

[0084] Fluid level changes inside the well / tank result in pressure changes in the air in the tube 25 , which in turn produce certain stresses on the transducer 15 .

[0085] The second part 13 of the device 10 is contained in the electronics section 18 of the electric pump 11 , outside the compartment 20 , in the subsection 29 .

[0086] The transducer 15 is encapsulated in a second portion 13 which is co-molded around the transducer 15 , which portion isolates the transducer 15 and renders it impermeable.

[0087] The operation of the device 10 according to the invention is as follows.

[0088] The user records the value of the well / tank size in the user interface of the electric pump 11 .

[0089] An air pressure sensor in the first part 12 of the device 10 is data linked via a PLC to the management and control element 40 of the device 10 and / or to the user interface of the electric pump 11 , which air pressure sensor measures the atmospheric pressure.

[0090] The pressure transducer 15 simultaneously measures the pressure inside the well / tank.

[0091] The management and control element 40 of the device 10 and / or the user interface of the electric pump 11 calculates the difference between these two pressures (ambient and well / tank), returning a value for the level of the well / tank calculated based on the dimensions initially entered therein.

[0092] In practice, it has been found that the invention achieves the intended aim and objects, providing a device for detecting the level of a well / tank which can be easily installed by the user and at any time.

[0093] The invention provides a device for detecting the liquid level of a well / tank, which device is at least partially integrated in an electric pump used in the well / tank and has a small space occupation.

[0094] Furthermore, the invention provides a device for detecting the liquid level in a well / tank which allows avoiding the need to provide dedicated access to the well / tank for its power supply and its operation, but exploits the same access to the well / tank as used by the electric pump with which the device is at least partially integrated.

[0095] Finally, the present invention provides an electric pump comprising a device for detecting the liquid level in a well / tank, which device enables the above-listed aims and objectives to be achieved.

[0096] The invention thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims; furthermore, all the details may be replaced by other technically equivalent elements.

[0097] In practice, the materials used (as long as they are compatible with the specific use), as well as the possible shapes and dimensions, may be any according to requirements and the state of the art.

Claims

1. A system for detecting the liquid level of a well or tank, the system comprising: An electric immersion pump (11) having a vertical extension in the use configuration and comprising a containment vessel (19) inside which there are: a wet section (16) comprising an inlet portion and a delivery portion and one or more impellers (33) keyed to a shaft (34), each impeller having its own diffuser and interposed between the inlet portion and the delivery portion, - an electromechanical part (17) comprising motor means (35) for moving the shaft, - an electronics part (18) comprising a compartment (20) inside which is housed an assembly (21) for the control and actuation of the electric immersion pump (11), said control and actuation assembly (21) being provided with a circuit board (36), A device (10) for detecting the liquid level in a well or tank, which is at least partially integrated in the electric immersion pump (11), the device (10) comprising: - management and control elements (40) of electronic type, a first part (12) comprising an air pressure sensor, said air pressure sensor being physically / electrically connected to said management and control element (40), - a second part (13) comprising a pressure transducer (15) and connected to the management and control element (40) via a wireless connection, Features: The control and actuation assembly (21) is connected to a user interface of the electric immersion pump (11) and comprises a communication device (22) of the NFC type, the communication device (22) being electrically connected to the user interface and / or the management and control element (40) of the device (10), said second part (13) of said device (10) comprises complementary communication means (23) of the NFC type, The communication means (22) are arranged near a socket (24) which is inside the electronic part (18) and accessible from outside the housing (19), the socket (24) being outside the compartment (20) and into which the second part (13) of the device (10) is plugged at least at the complementary communication means (23).

2. A system for detecting the liquid level of a well or tank according to claim 1, characterized in that The air pressure sensor has a data link to the management and control element (40) via a PLC.

3. The system for detecting the liquid level of a well or a tank according to claim 1, characterized in that The electric immersion pump (11) comprises mechanical means for engaging the second part (13) of the device (10), the second part (13) of the device (10) comprising corresponding complementary mechanical means.

4. The system for detecting the liquid level of a well or a tank according to claim 1, characterized in that The transducer (15) is laterally adjacent to the complementary communication device (23) and is electrically connected to the complementary communication device (23).

5. The system for detecting the liquid level of a well or a tank according to claim 1, characterized in that The device (10) comprises a tube (25) extending from the transducer (15), the tube (25) extending along one side of the electric immersion pump (11) in an adapted conduit (26), the conduit (26) having a vertical extension, the tube (25) leading into a substantially bell-shaped element (28) communicating therewith, the substantially bell-shaped element (28) being arranged substantially outside the housing (19), at the wet part (16) of the electric immersion pump (11).

6. The system for detecting the liquid level of a well or tank according to claim 1, characterized in that The second part (13) of the device (10) is contained in the electronics section (18) of the electric immersion pump (11), outside the compartment (20), and in a subsection (29).

7. The system for detecting the liquid level of a well or tank according to claim 1, characterized in that The management and control element (40) of the device (10) is connected to the user interface of the electric immersion pump (11) and / or is consistent with the user interface of the electric immersion pump (11).

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