“GAS REGULATING APPARATUS”

FIELD OF THE INVENTION

The present invention concerns a gas regulating apparatus, suitable to be used preferably but not exclusively in association with a burner for a boiler or other apparatuses fed with gas or with an air/gas mixture, such as for example a storage water heater, stoves, ovens, fireplaces, heating apparatuses, or suchlike.

The present invention in particular can be used in the field of heating apparatuses known as “furnaces” which provide to heat, by means of a burner, air or water to be circulated inside a pipe system of a building.

BACKGROUND OF THE INVENTION

It is known that gas-fed apparatuses have high efficiency and hygienic combustion only when the correct composition of the air/gas mixture is maintained in the range of available heat flows.

Known gas regulating apparatuses generally comprise a pressure regulator suitable to define the delivery pressure of the gas supplied to the burner, keeping it around a predefined value regardless of the gas pressure at entry.

The gases used can be different, for example natural gas (NG), propane, methane, or LPG (Liquefied Petroleum Gas, also known as Liquid Propane Gas). These gases require different operating pressures from one another. In the event that the type of gas used has to be changed, it is normally necessary to replace the regulating apparatus, or at least to replace one or more components, in particular the spring, and to remodulate the regulation. This replacement is necessary because the spring needed to cope with the different working pressures of the different gases should be oversized, leaving the problems unresolved both in terms of overall size of the pressure regulator and of the spring, when the latter is elongated and compressed, and also in terms of the correct alignment of the spring itself.

Furthermore, the operations required to replace the spring could cause damage to the regulation membrane or even an incorrect positioning of one of the components, leading to the incorrect operation of the regulating apparatus.

During this operation by the operator, the seal of the valve or the functioning of the members or components could also be compromised, also entailing possible risks related to safety.

Furthermore, the regulating apparatus may not be easily accessible for an operator, as for example in the case of application in heating apparatuses known as “furnaces” which provide to heat air or water to be circulated also by means of suitable fans inside a system of pipes of a building.

Some known solutions to solve this problem provide to use two different pressure regulators inside the same regulating apparatus, each provided with a spring and each suitable to regulate a maximum or minimum pressure value. In such solutions, two gas circuits are generally also provided, disposed in parallel to each other; when the regulating apparatus is set to a minimum value, only one circuit is kept open, while when the regulating apparatus is set to a maximum value both circuits are operational. In any case, if it is necessary to change the type of gas used, it is necessary to replace both springs.

Since they require a doubling of the components, these solutions are somewhat expensive in terms of production.

Furthermore, since these solutions require the use of specific components for each application, they are not very versatile and, consequently, do not allow any design flexibility in the choice of components and their conformation.

These solutions are mainly used in regulating apparatuses that provide pressure regulators of the piloted or servo-assisted type, which are generally more complex and for which the resulting increase in costs is proportionally limited. However, these solutions are not applicable to regulating apparatuses that use pressure regulators of the direct type, since the increase in costs in proportional terms would be much greater. Document US 2012/0255536 A1 describes a gas heating apparatus of a known type and suitable to be used with different types of gas, which comprises a gas selection valve provided with a first and second path for the gas, each associated with a respective valve and each communicating with a respective pressure regulator configured to operate at a determinate predefined pressure for a specific gas. The two pressure regulators are put in communication with the same outlet conduit which can be connected to the burner by means of a nozzle that operates in a differentiated manner depending on the working pressure of the gas used.

Documents WO 2014/008142 A1 and EP 2 584 258 A2 also describe gas heating apparatuses of a known type which provide to use a selection valve for the type of gas, which defines a first and a second path for the gas, each of which is connected to a respective pressure regulator suitable to operate at a predefined pressure in relation to the type of gas.

The apparatuses described in the above documents all have the same disadvantage that they require a duplication of the components necessary to obtain a regulation of the pressure at exit, with a consequent increase in costs and overall sizes.

There is therefore a need to perfect and provide a gas regulating apparatus which overcomes at least one of the technical disadvantages mentioned above.

The present invention intends to provide a gas regulating apparatus which guarantees optimal operation for a wide range of supply pressures and which is suitable for different types of gas without the need for substantial interventions.

Another purpose of the invention is to provide a regulating apparatus which is economical, reliable and safe.

Another purpose of the invention is also to provide a regulating apparatus which can be installed in external spaces, without the risk of condensation forming inside and which can function correctly in a wide range of temperatures.

Another purpose of the invention is to provide a regulating apparatus which is safe against possible damage by third parties.

The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages.

SUMMARY OF THE INVENTION

The present invention is set forth and characterized in the independent claim, while the dependent claims describe other characteristics of the present invention or variants to the main inventive idea.

In accordance with the above purposes, the present invention concerns a gas regulating apparatus suitable to be used in association with burners of apparatuses fed with gas or with mixtures of air and gas, such as in particular in heating apparatuses known as “furnaces”, but also boilers, storage water heaters, stoves, ovens, fireplaces, heating apparatuses and suchlike.

The regulating apparatus comprises a single direct type pressure regulator configured to regulate the pressure of the gas along a delivery conduit and keep it around a predefined value.

The pressure regulator comprises an elastic element, connected to a valve body mobile with respect to an aperture for the passage of the gas, and acting on it in an axial direction.

The valve body comprises a shutter, having a shape at least partly mating with the passage aperture, and a stem, on one end of which the elastic element is connected and acts.

According to one aspect of the present invention, the elastic element comprises at least one low stiffness zone and at least one high stiffness zone, that is, it has a differentiated stiffness.

The elastic element, in particular, is configured to have at least a first elastic constant in a first operating condition and at least a second elastic constant, greater than the first elastic constant, in a second operating condition.

The second operating condition differs from the first operating condition in particular for the operating parameters and the characteristics of the gas being used.

Thanks to the presence of the zones with low and high stiffness, the elastic element can therefore provide a different resistance according to the force applied to it, allowing the pressure regulator to adapt to different operating pressures.

Thanks to the provision of an elastic element with differentiated stiffness inserted in a single pressure regulator, it is possible to quickly adapt the latter and therefore the gas regulating apparatus if using gases that require different operating pressures, without needing to provide neither a duplication of pressure regulators, each suitable to operate at a given operating pressure, nor selection valves that regulate the passage of gas toward one or the other of such pressure regulators.

The apparatus according to the invention is therefore extremely compact and comprises a smaller number of components compared to known solutions, without a duplication thereof, but at the same time it has a great versatility of use.

According to some embodiments, the elastic element comprises a spring of the helical type with differentiated stiffness.

The high and low stiffness zones can be defined by respective groups of coils, which in the first operating condition are all active, while in the second operating condition are only partly active, that is, at least the coils of one group are positioned in contact with one another and therefore have no freedom of movement.

In this way, when a force smaller than a certain threshold value acts on the spring, both zones are operational, and the spring has overall a first elastic constant, that is, a total elastic constant, while when the force acting on the spring exceeds the threshold value, only the high stiffness zone remains active and the spring therefore has a second elastic constant, or partial elastic constant, greater than the total elastic constant.

This makes the regulating apparatus suitable to be used with different operating pressures, even very different from each other, without needing to replace the spring, requiring only to modify the pre-compression of the spring in such a way that it has the first or the second elastic constant as a function of the range of pressures involved. Once the pre-compression of the spring has been carried out to define its elastic constant, it is possible to carry out a finer calibration of the pre-compression of the spring in a known way, in order to regulate the desired pressure value, comprised between a minimum and a maximum. In this way, the regulating apparatus is suitable to be used with different types of gas, such as natural gas, methane, propane, LPG.

In other words, the gas regulating apparatus can be adapted for the use of different gases by means of simple operations, which can be performed even by personnel who do not need a high degree of specialization, without requiring any replacement of the spring or other components.

In particular, if a gas that requires medium-low operating pressures is used, such as for example natural gas, the spring can be pre-compressed in such a way as to assume the first operating condition, while if a gas that requires medium- high operating pressures is used, the spring can be pre-compressed in such a way as to assume the second operating condition.

In this way, since in the case of medium-high operating pressures the spring has a higher elastic constant, the space required for the elongation and compression of the spring is proportionally reduced, allowing to keep the overall sizes of the regulating apparatus contained. According to some embodiments, the helical spring can be produced as a variable pitch spring having a plurality of coils, comprising at least one first group of coils, disposed with a first pitch with respect to each other, defining the low stiffness zone, and a second group of coils, disposed with a second pitch, greater than the first pitch, defining the high stiffness zone.

According to some embodiments, all the coils can have substantially the same diameter.

According to possible variants, the helical spring can have a shape that is at least partly conical, or truncated-conical. In this case, a first group of coils with a larger radius defines the low stiffness zone, while a second group of coils with a smaller radius defines the high stiffness zone.

According to other variants, the elastic element can comprise a spring having a conical or spiral-shaped conformation, that is, bi-conical, with a non-constant section, comprising a combination of segments with variable diameter and pitch between the coils.

According to other embodiments, the pressure regulator comprises a first membrane and a second membrane, both connected to the valve body and to a housing of the pressure regulator, and defining a compensation chamber, which is fluidically connected to the delivery conduit by means of a communication channel made through in the mobile valve body.

Preferably, the following are disposed along the delivery conduit:

- the pressure regulator

- a safety valve, preferably comprising at least one solenoid valve to selectively open and close a passage aperture in the delivery conduit, respectively to allow or prevent the passage of gas through it.

The purpose of the safety valve is to close the delivery conduit preventing the passage of gas if there is no electric power supply, or if it is necessary to interrupt the supply of gas to a burner.

According to some embodiments, the pressure regulator is disposed upstream of the safety valve along the delivery conduit, so as to always be in equilibrium with respect to the inlet pressure. In this way, when the safety valve is opened, it can immediately start to operate at steady state, without unwanted delays or transitory states caused by the need to adapt to a sudden change in the inlet pressure, as would be the case if the pressure regulator were located downstream of the safety valve. This aspect helps to eliminate any problems caused by an excessive rise in the pressure within the regulating apparatus, or downstream thereof. Furthermore, in the event that the type of gas used is changed, this disposition allows to quickly adapt the pressure regulator to the new type of gas, before activating the regulating apparatus.

According to other embodiments, the pressure regulator comprises a modulator unit provided with a movement member mobile in an axial direction configured to act on the elastic element in order to compress it and define its load. In this way, it is possible to obtain a regulation of the outlet pressure on several levels.

In this case, the mobile movement member can slide through a hole provided on a covering element, or a wall, of the delivery conduit. This solution, in combination with the spring with differentiated flexibility, allows to obtain a precise regulation of the pressure at defined values, even with a direct type pressure regulator, allowing to obtain results that are comparable to those obtained with piloted or servo-assisted pressure regulators, keeping costs low.

According to possible variants, the pressure regulator comprises an adjustment member, such as for example a screw, which acts on the spring to define its load. This solution allows to modify the outlet pressure of the gas by setting it to a desired value.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects, characteristics and advantages of the present invention will become apparent from the following description of some embodiments, given as a non-restrictive example with reference to the attached drawings wherein:

- fig. 1 schematically shows a gas regulating apparatus according to a first embodiment of the present invention;

- fig. 2 is a section view along a longitudinal median plane of the gas regulating apparatus of fig. 1 ;

- fig. 2a is an enlarged detail of fig. 2;

- fig. 3 is a schematic section view of a gas regulating apparatus in accordance with a second embodiment; - fig. 4 is a schematic section view of a gas regulating apparatus in accordance with a third embodiment;

- fig. 5 is a partly sectioned three-dimensional view of a pressure regulator according to some embodiments described here;

- fig. 6 is a section view of a pressure regulator according to some variants described here;

- fig. 7 is a three-dimensional view of a filtering device according to some embodiments described here;

- fig. 8 is a bottom view of the regulating apparatus of fig. 1 with the delivery conduit disposed vertically, in which an anti-tampering device and a water collection cavity are visible;

- fig. 9 is a schematic graph showing the operation of a double flexibility spring in two different operating conditions.

We must clarify that in the present description and in the claims the terms lower, upper and low, with their declinations, have the sole function of better illustrating the present invention with reference to the drawings and must not be in any way used to limit the scope of the invention itself, or the field of protection defined by the attached claims.

Furthermore, the people of skill in the art will recognize that certain sizes or characteristics in the drawings may have been enlarged, deformed, or shown in an unconventional or non-proportional way in order to provide a version of the present invention that is easier to understand.

To facilitate comprehension, the same reference numbers have been used, where possible, to identify identical common elements in the drawings.

DESCRIPTION OF SOME EMBODIMENTS Fig. 1 concerns a gas regulating apparatus 10, configured to be used, preferably but not exclusively, in association with burners for boilers, heating apparatuses also known as “furnaces”, or other apparatuses fed with gas or air/gas mixtures of a known type and not shown in the drawings.

The gas-fed apparatuses in question comprise boilers, storage water heaters, stoves, ovens, fireplaces, or other similar or comparable apparatuses in which there is at least one burner fed with LPG, natural gas (NG), methane, propane, or others gas, or air/gas mixtures. The regulating apparatus 10 comprises a delivery conduit 11 which extends from an inlet end 12 to an outlet end 13.

The inlet 12 and outlet 13 ends can be disposed aligned along a longitudinal axis X of the regulating apparatus 10 (figs. 1-2 and 4), or be disposed orthogonal to each other (fig. 3), or even possibly disposed at a different angle.

The delivery conduit 11, during use, can be connected with the inlet 12 to a gas supply source, and with the outlet 13 to a gas burner, both not shown.

According to some embodiments, the regulating apparatus 10 comprises a pressure regulator 14 disposed in the delivery conduit 11.

In particular, the regulating apparatus 10 comprises a single delivery conduit 11 and a single pressure regulator 14 disposed therein.

The pressure regulator 14 is of the direct type and it is configured to regulate the gas pressure in the delivery conduit in such a way as to maintain, downstream with respect to the pressure regulator 14, a gas pressure value substantially constant around a predefined value.

Preferably, the pressure regulator 14 is of the direct and compensated type.

The regulating apparatus 10 also comprises a safety valve 15 disposed along the delivery conduit 12.

The pressure regulator 14 comprises a housing 16, provided with through slits 31 and a seating that defines an aperture 17 for the passage of the gas, and a valve body 18 mobile with respect to the aperture 17.

The valve body 18 comprises a stem 19a and a shutter 19b, which has a shape at least partly mating with that of the aperture 17 with which it cooperates to adjust the size of a section for the passage of the gas.

The valve body 18, or at least the shutter 19b, can be made of plastic material, so as to guarantee greater flexibility even in different conditions of use, both in terms of operating pressures and also in terms of temperatures and environmental conditions.

According to some embodiments, inside the delivery conduit 11 there is provided a support structure 46, having a shape at least partly mating with that of the pressure regulator 14 which, during use, is positioned therein. Packings 47 can be provided, disposed between the pressure regulator 14 and the support structure 46 to create a sealed coupling between the two components. The pressure regulator 14 comprises a first regulation membrane 20 connected to the stem 19a of the valve body 18 and configured to move the valve body 18 with respect to the aperture 17 in response to the variations in gas pressure, so as to maintain at exit a gas pressure and a flow rate substantially constant around a predefined value.

The regulation membrane 20 delimits, together with a covering element 36 of the delivery conduit 11, a regulation chamber 22 substantially at atmospheric pressure, which is separated from the delivery conduit 11.

The pressure regulator 14 also comprises an elastic element 23 connected to the stem 19a of the valve body 18 and configured to exert an elastic force thereon in an axial direction Y 1.

The axial direction Y 1 can be substantially orthogonal to the longitudinal axis

X.

The elastic element 23 helps to define the gas pressure downstream of the aperture 17 in relation to a compression force applied to it and in cooperation with the regulation membrane 20.

According to one aspect of the invention, the elastic element 23 has a differentiated stiffness.

By term “differentiated stiffness” we mean that the elastic element 23 comprises at least one low stiffness zone ZL and at least one high stiffness zone ZH, which help to define different elastic constants kxox, kp _AR x in different operating conditions.

In other words, the zones with high and low stiffness ZH, ZL provide greater or lesser resistance, respectively, to a force applied on the elastic element 23 in an axial direction.

According to some embodiments, the elastic element 23 comprises a spring 23 a of the helical type.

According to some embodiments, the elastic element 23 consists of a spring 23a of the helical type with differentiated stiffness.

According to some embodiments, the spring 23 a is made as a variable pitch spring comprising at least one first group of coils Gl, distanced by a first pitch PI with respect to each other and defining a low stiffness zone ZL, and at least one second group of coils G2, distanced by a second pitch P2, greater than the first pitch PI, and defining the high stiffness zone Z _H .

The coils can all have the same diameter, or even different diameters, for example differentiated between one group and another, or progressively variable.

As can be seen in the graph shown in fig. 9, when a gas that requires low operating pressures is used (for example between 2.5 and 10 mbar), such as for example natural gas (NG), both groups of coils Gl, G2 are active. In this first operating condition OP1, the spring 23 a behaves as a linear spring having a first elastic constant krox, that is, an overall elastic constant, given by the totality of the coils of the spring 23a.

On the contrary, when a gas that requires medium-high operating pressures is used (for example between about 10 and 30 mbar), such as for example LPG, the coils of the first group Gl are placed in contact and clamped with each other, and therefore only the coils of the second group G2 are active. In this second operating condition OP2, the spring 23 a behaves as a linear spring having a second elastic constant kp _ART , that is, a partial elastic constant, determined only by the active coils.

Thanks to this conformation, a single pressure regulator 14 can simply be adapted to be used with one or the other type of gas without needing to replace the spring, but simply by adjusting the compression of the spring and thus determining the most suitable operating condition.

The partial elastic constant kp _ART can be calculated using the following formula:

By way of example, the spring 23 a can have a partial elastic constant kp _ART comprised between 1.5 and 3 times the total elastic constant krox.

In this way, when a force smaller than a predefined threshold level Ft is applied to the spring 23 a, the spring 23 a assumes the first operating condition OP1 and the total elastic constant krox, while when a force greater than the threshold level Ft is applied, it assumes the second operating condition OP2 and the partial elastic constant kp _A x.

According to possible variants, not shown, the elastic element 23 comprises, or consists of, a spring 23 a of the helical type with differentiated stiffness having a conical or truncated cone shape. In this case, a first group Gl of coils with a larger radius can define the low stiffness zone ZL, while a second group G2 of coils with a smaller radius can define the high stiffness zone ZH.

According to other embodiments, the elastic element 23 can comprise, or consist of, a spring 23 a of the helical type having a conformation comprising a combination of segments with a constant diameter, or with a variable diameter, with a variable or constant pitch between the coils.

According to other embodiments, the pressure regulator 14 comprises a second membrane, or compensation membrane 24, which defines, together with the regulation membrane 20, a compensation chamber 25.

The compensation membrane 24 is connected to the valve body 18, in particular to one end of the stem 19a, and to the housing 16, in an intermediate position between the first regulation membrane 20 and the aperture 17.

The compensation chamber 25 is fluidically connected to the delivery conduit 11 by means of a communication channel 26.

In particular, the valve body 18 is at least partly hollow and the communication channel 26 is made through it, that is, through the shutter 19b and the stem 19a.

According to some embodiments, the communication channel 26 has a reduction in section 31 between an inlet 27 and an outlet 28.

In particular, upstream of the reduction in section 31, the communication channel 26 can have a first diameter D1 and, downstream of the reduction in section 31, it can have a second reduced diameter D2 comprised between 0.4 and 0.6 times the first diameter D1.

According to possible solutions, for example described with reference to fig. 5, inside the communication channel 26 there can be disposed an obstruction element 29, which defines a necking of the communication channel 26. The obstruction element 29 has the function of slowing down the passage of the gas toward the compensation chamber 25.

In this way, the desired outlet pressure value of the gas is not obtained instantaneously but gradually, preventing explosions or other problems from occurring, which could occur if the pressure in the delivery apparatus 10, 110 rises too fast. This problem is particularly felt in applications of the regulating apparatus 10, 110 in burners of the “furnace” type. The obstruction element 29 can be provided with an orifice 30 having a first minimum diameter Dminl, smaller than the reduced diameter D2 of the zone with the reduction in section 31. For example, the minimum diameter Dminl can be comprised between 0.4 and 0.6 times the reduced diameter D2.

According to other embodiments, described with reference to fig. 6, in addition or as an alternative to the obstruction element 29, a gas deceleration element 75 can be provided in the communication channel 26.

The deceleration element 75 can be made in the shape of a capsule, and be inserted and positioned inside the stem 19a, for example in proximity to the inlet hole 27.

The capsule-shaped deceleration element 75 can be clamped in position by means of a same-shape coupling, for example a snap-in or high interference coupling.

According to some embodiments, the deceleration element 75 can have a calibrated hole 76 having a second minimum diameter Dmin2 comprised between about 0.05 and 0.2 times the reduced diameter D2.

The second minimum diameter Dmin2 can be comprised between 0.2 and 0.5 times the first minimum diameter Dminl.

The use of the capsule- shaped deceleration element 75 allows to have better precision in the creation of the calibrated hole 76 compared to the obstruction element 29 in correspondence with the narrowing of the communication channel 26.

Furthermore, in the event that both the obstruction element 29 and also the deceleration element 75 are present, a volume to be filled is defined between the two components; by appropriately choosing the sizes of the respective holes 30, 76 it is possible to optimize the slow start-up times according to the result to be obtained.

The pressure regulator 14 is preferably disposed upstream of the safety valve 15 along the delivery conduit 11, in such a way as to always be in equilibrium with respect to the pressure of the gas at entry.

The gas at entry enters the housing 16 of the pressure regulator 14 through the passage slits 21 and accumulates in the space 32 comprised between the compensation membrane 24 and the aperture 17, until it reaches a pressure sufficient to exert a thrust on the obstructor 29 in order to move it away from the aperture 17.

When the aperture 17 is open, the gas can flow into the inlet conduit 11 and flow through the communication channel 26 until it reaches the compensation chamber 25.

According to some embodiments, the gaseous flow can enter the housing 16 in the direction of the longitudinal axis X.

According to other embodiments, the gaseous flow can enter the housing 16 laterally, in a direction transverse to the longitudinal axis X.

The regulating apparatus 10, according to the embodiments described in figs. 1-3, can comprise a modulator unit 33 configured to cooperate with the spring 23 a of the pressure regulator 14 in such a way as to obtain different operating modes, and in particular a plurality of levels of modulation of the gas pressure between a switched on and a switched off state of the regulating apparatus 10, for example two or more.

The modulator unit 33 comprises a movement member 34 mobile in the axial direction Yl, configured to act on the spring 23a in order to compress it and define its load, and a drive device 35 configured to translate the movement member 34 into predefined positions in the axial direction Yl.

The drive device 35 can comprise a servomotor, a stepper motor, a motion conversion mechanism, a linear actuator, or other similar or comparable member.

The modulator unit 33 can be installed outside the delivery conduit 11, and a through hole 37 can be provided in the covering element 36 through which the movement member 34 can slide.

Thanks to the presence of the spring 23 a with differentiated flexibility, when the use of one or another type of gas is required, for example natural gas (NG), methane, propane, or LPG, it is not necessary to remove the modulator unit 33 in order to replace a spring with a different and more suitable elastic constant. Therefore the regulating apparatus 10 can be adapted to a different type of gas, simply through an appropriate calibration.

The modulator unit 33 can also comprise one or more mechanical adjustment members (not shown), for example screws, suitable to act on the movement member 34 and/or the spring 23 a in order to adjust the pre-compression of the latter and set the desired operating pressure.

According to possible solutions, two adjustment members can be provided, for example a first adjustment member to set a minimum value disposed in correspondence with an upper end of the movement member 34, and a second adjustment member to set a maximum value disposed in correspondence with an upper end of the drive device 35.

Thanks to the presence of the modulator unit 33, the pressure regulator 14 can be set to at least two different operating levels for each operating condition of the spring 23a.

By means of the mechanical adjustment members it is possible to carry out a first adjustment of the spring 23a in order to define its elastic constant, and a second adjustment, finer and more precise, in order to set a desired level of operating pressure selected at least between a minimum and a maximum as a function of the quantity of gas to be delivered. The passage from the minimum level to the maximum level, and vice versa, occurs through the action of the drive device 35 which moves the movement member 34.

Fig. 4 describes a variant of a gas regulating apparatus 110 in which, instead of the modulator unit 33, the pressure regulator 14 comprises only a mechanical adjustment member 38, such as for example a screw, which acts on the spring 23 in order to define its load.

In particular, the mechanical adjustment member 38 can perform two functions, that is, it can be used to carry out a first adjustment of the spring 23 to define its elastic constant, and a second adjustment of the spring to calibrate it around a desired optimum pressure value.

As stated, the regulating apparatus 10, 110, in both the variants described, can comprise the safety valve 15, which is configured to selectively open and close a passage for the gas in the delivery conduit 11, in order to allow or prevent the passage of the gas toward the outlet 13.

According to some embodiments, the safety valve 15 comprises at least one solenoid valve 50, 51.

According to possible solutions, two solenoid valves 50, 51 are provided, provided with respective valve bodies 52, 53 each cooperating with a respective aperture 54, 55, which are held in a normally closed position by two respective holding springs 56, 57.

According to the embodiments shown, the two solenoid valves 50, 51 are coaxial to each other.

The solenoid valves 50, 51 are configured to be positioned on each occasion in a position in which the respective aperture 54, 55 with which they are associated is open, in relation to the action of at least one electrically powered winding 58.

According to some embodiments, in the delivery conduit 11 there can be provided a support structure 48 configured to cooperate with the at least one solenoid valve 50, 51 in order to keep it in position, and in which the aperture 54, 55 is provided.

According to possible variants, not shown, two solenoid valves can be provided, separated from each other and located in succession to each other along the delivery conduit 11.

According to some embodiments, the safety valve 15 can comprise only one electrically powered winding 58, functionally associated with both solenoid valves 50, 51.

According to possible variants, the safety valve 15 can comprise two windings 58, each associated with a corresponding solenoid valve 50, 51.

According to possible embodiments, when the winding 58 is powered, it counteracts the holding force exerted by the two holding springs 56, 57 and it positions both solenoid valves 50, 51 in order to open the apertures 54, 55, so as to allow the gas to pass through them toward the outlet 13.

The safety valve 15 fulfills the safety function since, if it is necessary to intervene on the gas regulating apparatus 10, 110 or on the gas-fed apparatus connected to it, it can be activated to promptly interrupt the delivery of gas. In this case, the holding springs 56, 57, if not opposed by a force, return the valve bodies 52, 53 to the condition in which the respective apertures 54, 55 are closed.

According to possible embodiments, described in figs. 5 and 7, the regulating apparatus 10, 110 comprises a filtering device 39 disposed inside the delivery conduit 11, configured to prevent access into the latter of any solid particles or other impurities entrained by a gaseous flow at entry.

Any solid particles present in the delivery conduit 11, in fact, could damage one or more components, or at least prevent a correct operation thereof. For example, the solid particles could deposit in correspondence with the aperture 17, preventing the valve body 18 from positioning itself correctly with respect to the aperture 17, or possibly even from closing it.

According to some embodiments, the filtering device 39 has an annular shape and it is disposed around the pressure regulator 14, surrounding the latter substantially on the entire perimeter.

The filtering device 39 comprises a support body 40 on which a filtering element 41 is attached, suitable to allow the passage of gas and block any solid particles entrained thereby.

The filtering element 41 can have a continuous fabric with very dense meshes, or formed by a plurality of parts disposed in such a way as to completely surround the pressure regulator 14.

The filtering device 39 is therefore disposed completely inside the delivery conduit 11, and it is protected from possible damage.

The support body 40 has an annular shape correlated to the shape of the housing 16 of the pressure regulator 14, and it comprises first coupling members 42 which cooperate with mating second coupling members 43 of the housing 16 in such a way that, during use, the filtering element 41 is positioned in correspondence with the passage slits 21 and aligned with them.

The second coupling members 43 can comprise annular recesses or seatings suitable to accommodate and hold respective protruding teeth or lips of the second coupling members 42, or vice versa.

There can also be respective recesses 44 or protrusions made on the support body 40 and/or on the housing 16, which define a same-shape, or snap-in, coupling with each other.

According to some embodiments, the filtering device 39 comprises a packing 45 disposed in correspondence with the lower edge, configured to couple in a sealed way to the housing 16 of the pressure regulator 14 and to the support structure 46 inside the delivery conduit 11.

In this way, the gas flow coming from the inlet 12 can enter the space 32 inside the housing 16 only through the filtering element 41 and the passage slits 21, in such a way as to prevent the entry of any solid particles or dirt into the delivery conduit 11. According to some embodiments described here, the regulating apparatus 10, 110 comprises an anti-intrusion barrier 60 which has the function of preventing the insertion of tools or other instruments inside the delivery conduit 11 through the inlet 12.

The anti-intrusion barrier 60 also prevents direct access of the gas into the delivery conduit 11 in the longitudinal direction XI, thus entailing an access of the gas in the transverse direction.

This indirect path of the gas from the inlet 12 to the delivery conduit 11 determined by the presence of the anti-intrusion barrier 60 results in a better distribution of the gas in the pressure regulator 14, allowing a quick adaptation of the pressure regulator 14 and the spring 23 if the regulating apparatus 10, 110 is activated, for example following a change in the type of gas to be used.

The anti-intrusion barrier 60 can be seen for example in fig. 8, which shows a bottom view of the regulating apparatus 10 of fig. 1, rotated by 90°, so that the inlet 12 is positioned at the top and the outlet 13 at the bottom.

The anti-intrusion barrier 60 can comprise a U-shaped sheet 61 comprising a deviation wall 62 and lateral walls 64 that extend from opposite sides of the deviation wall 62.

The deviation wall 62 is disposed inside the delivery conduit 11 in proximity to the inlet 12, but distanced from it in order to define at least one transit channel 70 for the gas flow.

The deviation wall 62 is solid, that is, full, and has the function of preventing and/or blocking the introduction of tools or other instruments from the inside of the delivery conduit 11 through the inlet 12.

The lateral walls 64 define, together with the external walls 66 of the delivery conduit 11, and containing walls 67, the at least one transit channel 70 for the gaseous flow.

The sheet 61, or at least the deviation wall 62, can have a flared shape and can at least partly define the support structure 46 of the pressure regulator 14.

Through slits 63 are provided on the lateral walls 64 which put the, or each, transit channel 70 in communication with the delivery conduit 11, and in particular with the pressure regulator 14 disposed therein.

In this way, the gaseous flow which enters through the inlet 12 impacts against the deviation wall 62 and is diverted and conveyed adhering to the latter in the transit channel/s 70 toward the through slits 63, through which it enters the pressure regulator 14. The arrows F in fig. 8 indicate the path of the gas flow between the inlet 12 and the pressure regulator 14 along the transit channels 70.

The through slits 63 are disposed substantially aligned with the filtering device 39 and the through slits 21 of the housing 16.

According to some embodiments, the gas regulating apparatus 10, 110 also comprises a single or double collection cavity 65 in which any condensation or water particles entrained by the gas flow at entry can be collected, preventing them from entering the delivery conduit 11.

This solution makes the regulating apparatus 10, 110 according to the invention suitable to even be installed outdoors, as normally occurs in the case of “furnace” heating apparatuses due to the sizes and the noise generated by the fans to move the air.

This solution allows the regulating apparatus 10, 110 to be adaptable to a wide range of temperatures, for example comprised between - 40 °C and + 80 °C, as commonly required by the practice of the sector in North American applications, and allows it to be used with gases that can have different capacities of entrainment of drops of condensation or humidity.

The collection cavity 65 is made in continuity with the transit channel 70.

According to some embodiments, two collection cavities 65 can be provided, disposed on one side and on the other of the deviation wall 62.

The collection cavities 65 are preferably made in continuity with the transit channels 70, and the deviation wall 62 also acts as a conveyor for any water present in the gaseous flow.

In particular, the collection cavities 65 can have a box-like shape, and each can be delimited by a lateral wall 64, an external wall 66 of the delivery conduit 11, a containing wall 67 and a bottom wall 68.

In the part opposite the containing wall 67, the collection cavity 65 can be delimited by a covering element 71, visible in figs. 2-4, which can be attached to a lower portion 72 of a casing 73 of the regulating apparatus 10, 110. For this purpose, the lower portion 72 can be provided with holes 69 in which screws, pins or other attachment means of a known type can be inserted and attached. When the regulating apparatus 10, 110 is oriented as in fig. 8, with the inlet 12 facing upward, any water or condensation entrained by the gaseous flow through the inlet 12 slides on the deviation wall 62, is conveyed into a transit channel 70 and falls by gravity into the collection cavity 65 (see arrows W in fig. 8). It is clear that modifications and/or additions of parts may be made to the gas regulating apparatus 10, 110 as described heretofore, without departing from the field and scope of the present invention as defined by the claims.

It is also clear that, although the present invention has been described with reference to some specific examples, a person of skill in the art shall certainly be able to achieve many other equivalent forms of regulating apparatus, all coming within the field of the present invention.

In the following claims, the sole purpose of the references in brackets is to facilitate reading and they must not be considered as restrictive factors with regard to the field of protection defined by the claims.