Patent Description:
The invention is applied in particular for the detection of the level of a well/tank in which an electric immersion pump is used.

The present invention also relates to an electric pump provided with such a device.

Electric immersion pumps are electric pumps that are used inside wells and/or tanks to draw the liquid (normally water) contained therein.

One of the most strongly felt requirements on the part of the user is to know the level of the liquid in the well/tank and therefore its residual availability.

Currently, in order to have an idea of the level of the 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.

In the present description, the expression "free surface" is understood to refer to the separation surface between the liquid phase (liquid contained in the well/tank) and the gaseous phase (air).

Often, however, wells/tanks in which said immersion pumps are used are not easily or quickly accessible to the user.

For this reason, level probes, including immersion probes, are widely used.

These immersion probes are immersed in the well/tank, usually to the bottom, and measure the filling level or height of the well/tank according to the principle by which a liquid generates, with its relative density and the force of gravity, a weight force that increases proportionally with the filling level.

These probes comprise a measurement end, which contains for example a silicon strain gauge and the electronic devices for evaluating the variations of the former, from which one or more metallic cables with capillaries extend in order to compensate for atmospheric pressure.

The measurement of the level is provided by determining the difference between the ambient pressure, measured by a sensor outside the tank, and the pressure measured by the probe.

As an alternative, level probes of the float type are used, for example.

These float probes comprise, inside the float, a magnet which moves as a function of the movement of the level of the well/tank and interacts with one or more electrical contacts of the reed type, modifying their electrical condition.

However, all these known methods have some drawbacks.

First of all, for their operation, these probes have at least one cable that must be connected to a dedicated user interface that is external to the well/tank.

This entails considerable space occupations and the need to provide an access to the tank also for this cable, in addition to the one dedicated to the passage of the power supply cable of the electric pump and to the one for the passage of the delivery duct.

Furthermore, the user is forced to use both an electric pump and a level probe and this entails for the user:.

Moreover, a drawback is caused by the fact that the installation of the probe normally must be performed by expert personnel and cannot be performed easily by the user.

The relevant prior art also comprises the patent documents <CIT>, <CIT>, <CIT>, <CIT> and <CIT>. <CIT> relates to a a progressive-cavity pump comprising a motor speed control, a pump pressure sensor located at the pump depth; a casing pressure sensor located at the casing head of the well and a programmable computer connected to the first and second pressure sensors and the motor speed control.

The aim of the present invention is to provide a device for detecting the level of a well/tank and an electric immersion pump with such a device which are capable of improving the background art in one or more of the aspects indicated above.

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

Another object of the invention is to provide a device for detecting the level of a well/tank that is at least partially integrated in an electric pump used in said well/tank.

A further object of the invention is to provide a device for detecting the level of a well/tank that has a reduced space occupation.

Another object of the invention is to provide a device for detecting the level of a well/tank without the need to provide a dedicated access to the well/tank for its power supply and its operation but utilizes the same access to the well/tank that the electric pump used.

Another object of the invention is to provide an electric pump which comprises a device for detecting the level of a well/tank capable of achieving the aim and objects listed above.

Another object of the present invention is to overcome the drawbacks of the background art in a manner that is alternative to any existing solutions.

Another object of the invention is to provide a device for detecting the level of a well/tank and an electric immersion pump with such a device that are highly reliable, relatively easy to provide and at competitive costs.

This aim, as well as these and other objects which will become better apparent hereinafter, are achieved by a system for detecting the level of a well/tank according to claim <NUM>.

Further characteristics and advantages of the invention will become better apparent from the description of a preferred but not exclusive embodiment of the device for detecting the level of a well/tank and of the electric pump with such a device, according to the invention, illustrated by way of non-limiting example in the accompanying drawings, wherein:.

With reference to the figures, a device for detecting the level of a well/tank, according to the invention, is designated generally by the reference numeral <NUM>.

The device <NUM> is applied to an electric pump <NUM> and is at least partially integrated therein.

The air pressure sensor is for example a sensor of the type known by the trade name "Infineon DPS310".

The pressure transducer is for example the transducer of the type known by the trade name "Honeywell MPRLS0025PA00001A".

The first portion <NUM> is external to the well/tank.

The air pressure sensor has a data link to the electric pump <NUM> by means of the electrical mains <NUM>.

In particular, the air pressure sensor has a data link to the management and control element <NUM> via an electrical connection, utilizing so-called "power line" technology, also known as PLC ("Power Line Communication").

The electric pump <NUM> is of the immersion type, is extended vertically in the configuration for use and comprises a containment shell <NUM>, inside which there are:.

The control and actuation assembly <NUM> is connected to the user interface and comprises communication means <NUM> of the NFC type.

The NFC communication means <NUM> are constituted by an antenna.

These communication means <NUM> are electrically connected to the user interface and/or to the management and control element <NUM> of the device <NUM>.

The second portion <NUM> of the device <NUM> comprises complementary communication means <NUM> of the NFC type.

The electric pump <NUM> comprises mechanical means for the engagement of the second portion <NUM> of the device <NUM>, which comprises corresponding complementary mechanical means.

The antenna <NUM> is arranged proximate to a receptacle <NUM>, which is internal to the electronic section <NUM> and can be accessed from the outside of the shell <NUM> but is external to the compartment <NUM>.

The receptacle <NUM> is adapted for the insertion of the second portion <NUM> of the device <NUM>, at least at the complementary NFC communication means <NUM>.

The complementary NFC communication means <NUM> are arranged in one end of the second portion <NUM>.

By means of the NFC communication between the antenna <NUM> of the control and actuation unit <NUM> and the complementary communication means <NUM> of the device <NUM> it is possible to install the device <NUM> without the need to physically/electrically connect its second portion <NUM> to the management and control element <NUM> and/or to the user interface.

This allows at the same time to reduce the risk of infiltrations within the compartment <NUM>.

Furthermore, the user can purchase the electric pump <NUM> and decide later if and when to purchase and install the device <NUM>.

By virtue of the NFC communication between the antenna <NUM> of the control and actuation assembly <NUM> and the complementary communication means <NUM> of the second portion <NUM>, the user can install autonomously and easily the device <NUM> on the electric pump <NUM>.

In the specific case, the receptacle <NUM> of the electric pump <NUM> has such a shape and dimensions that it is substantially shaped complementarily to at least the complementary communication means <NUM>, so as to ensure their easy insertion and coupling of the means inside it.

The second portion <NUM> of the device <NUM> has a substantially quadrangular profile and is substantially flat.

The pressure transducer <NUM> is laterally adjacent and electrically connected to the complementary communication means <NUM> and converts the pressure into an electrical signal which is then sent to the management and control element <NUM> and/or to the user interface.

The transducer <NUM> is an integrated circuit which comprises:.

The device <NUM> comprises a tube <NUM>, made of plastic material, such as silicone, which extends starting from the transducer <NUM> toward the bottom of the tank.

In particular, the tube <NUM> runs along one side of the electric pump <NUM>, inside an adapted duct <NUM>, which has a vertical extension.

The tube <NUM> leads into a substantially bell-shaped element <NUM>, with which it communicates and which is arranged substantially at the wet section <NUM> of the electric pump <NUM>, outside the shell <NUM>.

The tube <NUM> contains air, and its particular shape and arrangement, inside the duct <NUM> and the substantially bell-shaped element <NUM>, and the presence of the substantially bell-shaped element <NUM> cause the liquid to be unable to rise up to the transducer <NUM> even when the electric pump <NUM> is immersed.

In this matter, the tube <NUM> is prevented from being full of water, altering the reading of the transducer <NUM>.

The electric pump <NUM> is in fact immersed vertically and during this step air is present inside the substantially bell-shaped element <NUM> and, due to the shape of said element, is unable to evacuate, remaining trapped inside the assembly constituted by:.

A level variation inside the well/tank causes a pressure variation of the air in the tube <NUM>, which in turn causes a certain stress on the transducer <NUM>.

The second portion <NUM> of the device <NUM> is contained in the electronic section <NUM> of the electric pump <NUM>, outside the compartment <NUM>, in a subsection <NUM>.

The transducer <NUM> is enclosed in the second portion <NUM>, which is comolded around the transducer <NUM>, portion which isolates and renders it impermeable.

The operation of the device <NUM> according to the invention is as follows.

The user records the values of the dimensions of the well/tank in the user interface of the electric pump <NUM>.

The air pressure sensor, in the first portion <NUM> of the device <NUM>, data-linked by means of a PLC to the management and control element <NUM> of the device <NUM> and/or the user interface of the electric pump <NUM>, measures the atmospheric pressure.

The pressure transducer <NUM> simultaneously measures the pressure inside the well/tank.

The management and control element <NUM> of the device <NUM> and/or the user interface of the electric pump <NUM> calculates the difference between these two pressures (ambient and well/tank), returning the value of the level of the well/tank, calculated on the basis of its dimensions entered initially.

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 that can be installed easily by the user and at any time.

The invention provides a device for detecting the level of a well/tank that is at least partially integrated in the electric pump used in said well/tank and has a small space occupation.

Moreover, the invention provides a device for detecting the level of a well/tank that allows to avoid the need to provide a dedicated access to the well/tank for its power supply and its operation, but utilizes the same access to the well/tank that is used by the electric pump with which it is at least partially integrated.

Finally, the invention provides an electric pump which comprises a device for detecting the level of a well/tank that is capable of achieving the aims and objects listed above.

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

In practice, the materials used, so long as they are compatible with the specific use, as well as the contingent shapes and dimensions, may be any according to the requirements and the state of the art.

This application claims priority from the <CIT>.

Claim 1:
System for detecting the level of a well or tank comprising:
an electric immersion pump (<NUM>), having a vertical extension in the configuration for use and comprising a containment shell (<NUM>) inside which there are:
- a wet section (<NUM>), which comprises an intake portion and a delivery portion and one or more impellers (<NUM>) keyed on a shaft (<NUM>), each with its own diffuser, and interposed between said intake portion and said delivery portion,
- an electromechanical section (<NUM>), which comprises motor means (<NUM>) for the movement of said shaft,
- an electronic section (<NUM>), comprising a compartment (<NUM>) inside which an assembly (<NUM>) for the control and actuation of said electric immersion pump (<NUM>) is contained, said control and actuation assembly (<NUM>) being provided with an electrical board (<NUM>), a device (<NUM>), at least partially integrated in the electric immersion pump (<NUM>), for detecting the level of a well or tank comprising:
- a management and control element (<NUM>), of the electronic type,
- a first portion (<NUM>), comprising an air pressure sensor, physically/electrically connected to said management and control element (<NUM>),
- a second portion (<NUM>), which comprises a pressure transducer (<NUM>) and is connected to said management and control element (<NUM>) by means of a wireless connection,
wherein said control and actuation assembly (<NUM>) is connected to a user interface of said electric immersion pump (<NUM>) and comprises communication means (<NUM>) of the NFC type, said communication means (<NUM>) being connected electrically to said user interface and/or to said management and control element (<NUM>) of said device (<NUM>),
said second portion (<NUM>) of said device (<NUM>) comprises complementary communication means (<NUM>) of the NFC type, and
said communication means (<NUM>) are arranged proximate to a receptacle (<NUM>), said receptacle (<NUM>) being internal to said electronic section (<NUM>) and being accessible from the outside of said shell (<NUM>), said receptacle (<NUM>) being external to said compartment (<NUM>), said second portion (<NUM>) of said device (<NUM>) being inserted in said receptacle (<NUM>) at least at said complementary communication means (<NUM>)