Description

The present invention relates, in general, to a filter system. More particularly, it relates to a filter system for systems using a liquid such as water or others.

The invention will be described below in the case in which it is applied in summer/winter thermal air conditioning systems where mud filters are used, but it can also be implemented in other types of systems where there is the presence of a filter system to filter the liquid flowing through the system.

As is known, thermal summer/winter air conditioning systems, in particular heating systems, can have problems due to the formation of metal oxide deposits.

To avoid such problems, the reference law (DM 26/2015) obliges the chemical conditioning of water in summer/winter air conditioning circuits.

Although such water treatment is carried out, it is still necessary to install a mud filter, usually placed in the return circuit of the heating system, as required by UNI 8065 standard of July 2019.

Mud filters can usually comprise a stainless steel mesh or a magnetic one or both.

Although having the same purpose, mesh and magnet operate differently. The steel mesh has a filtering action that retains all solid particles larger than the degree of filtration of the mesh, so as to retain the metal oxides formed in the circuit. The magnet attracts the ferromagnetic metal oxides to itself, so preventing them from being deposited in the heating circuit.

One problem with mud filters - and with all filters in general - according to known technique, is that it is difficult to understand when they are clogged and therefore are no longer performing their task. In fact, the only warning given by the filters according to the known technique is when the clogging of the mud filter is substantially complete, as there is a considerable reduction in the water flow rate in the circuit with considerable pressure drops which can block the boiler.

In addition, once a certain amount of ferromagnetic metal oxides have been deposited on the magnet, this latter is no longer able to perform its function.

In order to solve this problem, periodic maintenance of the mud filters is established, after which they must be cleaned or replaced.

As this periodic maintenance is carried out very frequently, this method is not cost-effective, as there is a risk of cleaning or replacing filters which are still efficient.

Furthermore, in order to avoid rather frequent cleaning, the nets used are usually made of large meshes, thus losing much of the protective function of the mud filter.

Another problem with the known technology of the mud filters is their connection configuration with the corresponding system. In fact, the hydraulic connection which is connected to the body of the mud filter is usually in a fixed position or in the best cases it can be rotated by 360°.

However, these connections are limited to a single inlet and outlet, so limiting flexibility and ease of installation.

A further problem with the known technology of mud filters is the limited installation space under the boiler. Normally all mud filters are equipped or must be equipped with a valve upstream and a valve downstream of the filter to allow the water to be shut off during maintenance and cleaning of the filter. The presence of these two valves makes the installation more complex and bulky.

In addition, conventional mud filters can be used as a point of entry into the thermal system for conditioning products. Usually this operation implies the disassembly of the glass and its filling with the conditioning product. Often this operation has to be repeated a few times in order to supply the sufficient amount of product.

There is a new method on the market that uses pressurized cylinders that inject the concentrated conditioning products into the mud filter. However, it is necessary to isolate the device from the system and carry out operations which are rather long, cumbersome and may lead to losses.

The object of the present invention is to provide a filter system which solves the problems of the known technique.

A further scope of the invention is to provide a filter system which can be cleaned or replaced when it is actually clogged or no longer efficient.

A further scope of the invention is to provide a filter system that can be easily installed to the respective system, regardless of the configuration of the latter, even when there is little installation space under the boiler.

A further scope of the invention is to provide a filter system facilitating the introduction of conditioning products into the heating system, also by means of pressurized cylinders.

According to the invention, these and other purposes are achieved by a filter system comprising a filter with an outlet duct and an inlet duct, said filter being suitable for being connected to a system, characterized in that it comprises a pressure switch disposed in the outlet duct and a signaling device connected to the pressure switch, so that the signaling device signals when the pressure is lower than a predetermined value, this because the signaling device compares the pressure P of the fluid measured by the pressure switch with a predetermined pressure value X.

In this way, if the pressure is lower than a predetermined value, it means that there is a pressure drop downstream of the filter due to a clogging of the filter itself, so making it necessary to clean it or due to another anomaly still to be checked.

To warn about such clogging, the filter system may include a signaling device, such as an alarm card, connected to a control unit.

Such a signaling device may be an acoustic device and/or a visual device. The signal may also be transmitted via Bluetooth, Wi-Fi, radio waves or other means.

Advantageously, the filter may comprise a seat for positioning one or more chemical tablets, capable of purifying and/or sanitizing the liquid flowing in the system.

In addition, a cross-shaped connection allows to choose the most convenient connection. This facilitates the horizontal and vertical orientation of the filter body, which can be adjusted at 360° as well as the connection to the boiler through an extended connection.

In fact, the cross-shaped connection comprises four connections, one of which has a length greater than the others; this makes it easier to connect to the boiler piping and avoids the need for a threaded socket that is usually used for this purpose.

Advantageously, the filter has a shut-off valve integrated in the filter, so avoiding the installation of an upstream and downstream valve to allow maintenance and cleaning of the filter, by reducing installation space and complexity.

Further features and details can be better understood from the description below, which is given as a non-limiting example, as well as from the annexed drawing table in which: figure 1 is a schematic side view of a filter system, according to the invention, mounted on an installation; figure 2 is an exploded schematic side view of the filter system of figure 1 ; figure 3 is a cross-sectional side view of a mud filter included in the filter system according to the invention.

With reference to the annexed figures, in particular to figure 1 , 10 indicates in its entirety a mud filter system suitable for retaining metal oxides, formed within a heating circuit.

The mud filter system 10 comprises a mud filter 12 and a cross-shaped connection 14 for connecting the mud filter 12 to the corresponding system.

The 4-way cross-shaped connection 14, which can be rotated by 360°, consists of a dedicated elongated connection for the boiler inlet and of two inlets at a choice, depending on the installation requirements.

In particular, the mud filter 12 comprises in turn a body 16 to which a glass 18 is screwed.

The body 16 is connected to the cross-shaped connection 14 by means of a bayonet coupling 20 which allows a 360° rotation of the same body 16 and therefore of the mud filter 12.

The body 16 houses a tap 22 which is controlled by a knob 24. The valve 22 allows the flow through the mud filter 12 to be blocked, but this blocking also prevents the flow of fluid through the cross-shaped connection 14.

In this way, it is not possible to bypass the mud filter 12 even if it is clogged or needs to be replaced, thus forcing the user to carry out the necessary maintenance. The glass 18 houses a magnet 26 and a stainless steel metallic net 28, in particular a fine mesh net. In particular, the net 28 is connected to the magnet 26 by a connecting means 27 made of ferromagnetic material, so that the net 28 is also made magnetic.

In order to increase the efficiency of retaining ferrous particles, the net 28 may be a martensitic stainless steel net that is easily magnetized.

Due to such a configuration, the efficiency of magnetic retention is greatly increased as the contact surface of the magnet with the circulating water is forced to go all in contact with the magnetic field.

As shown in figure 3, all water passing through the mud filter 12 is forced to pass through the net 28, which is made magnetic by the contact with the magnet 26.

Due to this configuration, it is possible to retain all magnetic particles suspended in the water passing through the mud filter 12.

The mud filter system 10 further comprises a pressure switch 30 connected to an alarm card 32 by means of a cable 34.

The alarm card 32 comprises a signaling device, in particular an acoustic and/or optical device.

The pressure switch 30 is arranged in the cross-shaped connection, precisely in an outlet duct, so as to measure the pressure of the fluid exiting the mud filter 12.

The pressure value measured by the pressure switch 30 is sent to the alarm card 32 in which a predetermined pressure value X has been set, which represents the maximum pressure value for which the mud filter is clogged.

In other words, for pressure values lower than this predetermined value X, the mud filter 12 is completely clogged and/or saturated, and should therefore be cleaned or replaced.

In fact, as a result of the clogging of the filtering metal net, the pressure of the fluid downstream of the mud filter decreases.

The alarm card 32 continuously compares the pressure value P measured by the pressure switch 30 with the predetermined pressure value X.

When the pressure P measured by the pressure switch 30 is lower than the predetermined value X, the alarm card 32 activates the signaling device.

In this way, the user will be warned by the signaling device that the mud filter 12 is clogged and he will clean and/or replace it.

In other words, when the net is filled of debris, it causes a pressure drop downstream of the mud filter 12 and the alarm card, and by means of the signaling device warns about this problem.

The net can then be cleaned. When the net is removed from the magnet, it temporarily loses its magnetic properties so that it can be easily cleaned of metal debris.

Furthermore, the mud filter system according to the invention comprises a single valve which is integrated into the mud filter, and thus is not external to it. Such a valve isolates the mud filter from the system to allow maintenance of the same. The advantage is the reduction of the installation space, the avoidance of the addition of the two valves normally installed and the facilitation of the operation of stopping the water with a single movement.

The mud filter system 10 according to the invention comprises, also, a loading unit comprising a non-return valve 36 coupled to a quick coupling 38, by means of which it is possible to introduce conditioning products into the thermal system, also by means of pressurized cylinders. In this way, the loading operation can be carried out very quickly and easily.

According to a variant of the invention, the alarm card can be connected to a phone line or to an internet network, for example via Wi-Fi or via Ethernet cable or other connection system, so as to send an e-mail message or an SMS to the user.

According to a further variant of the invention, the mud filter 30 comprises within itself a seat for positioning one or more tablets of a chemical product, suitable for inhibiting corrosion within the hydraulic system.

There may also be variants to be considered within the scope of the invention.

For example, instead of the acoustic device, a luminous device may be used, capable of signaling the decrease in pressure beyond a preset limit by means of a luminous signal, such as the switching on of one or more LED lights.

The filter system 10 according to the invention can be applied for all those devices dedicated to water treatment that during their normal operation can experience a drop in flow and consequently a drop in pressure.

By way of example, the filter system according to the invention can be applied for any automatic or non-automatic filter, or for any microfiltration system, so that the pressure switch warns the user of the need to clean and/or replace the filter element.

It should also be noted that the alarm system present in the system object of the invention, is also useful in all those cases in which there is a drop in pressure due to a generic anomaly of the system.

As mentioned above, the invention has been described in the case in which it is applied to a mud filter system, but it can also be included in a generic filter system for other applications.