TECHNICAL FIELD OF THE INVENTION

The present invention relates to a heat generating unit, such as a stove, in particular fed with two fuels, for example wood and pellet.

TECHNICAL BACKGROUND

Heat generators that can be fed both with wood and pellet have been proposed, wherein the wood is manually inserted into the combustion chamber by opening a main wing, while pellet is loaded into a tank under the combustion chamber and automatically fed in the latter from this tank.

The presence of the pellet tank and its lid under the combustion chamber can result in hot embers falling from the combustion chamber into the pellet tank, wherein the pellet loading operation would take place with the fireplace wing opened.

The national installation standards and the common practice for fuel-fed equipment include a floor protection for installation on combustible floors.

This protection must extend under the equipment, laterally and frontally to the fuel loading wing or to the access wing to the combustion chamber.

Therefore, there is a need to prevent the hot embers from accidentally falling from a combustion chamber in a fuel tank which can be opened frontally and at the foot of the fireplace.

OBJECTS OF THE INVENTION

An object of the present invention is to provide a new heat generator or stove.

Another object of the present invention is to provide a new heat generator, wherein the accidental falling of hot embers from a combustion chamber to an underlying fuel tank or vice versa is prevented.

Another object of the present invention is to provide a new heat generator which can be fed with two fuels, both wood and pellet, which is safer than traditional heat generators. Another object of the present invention is to provide a heat generator as mentioned above, which is also efficient and easy to produce.

According to one aspect of the invention a heat generating unit according to claim 1 is provided.

The dependent claims refer to preferred and advantageous embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Other characteristics and advantages of the invention will be more evident from the description of an embodiment of a heat generating unit, illustrated by way of example in the accompanying drawings wherein:

- figures 1 and 2 are perspective views slightly from above and from respective sides of a generating unit according to the present invention;

- figures 3 and 4 are perspective views of components of the generating unit of figure 1 with the second door unlocked and moved relative to a closed position;

- figures 5 to 7 are enlarged scale views of the components illustrated in figures 3 and 4;

- figures 8 and 9 are perspective views of components of the generating unit of figure 1 with the first door unlocked and moved relative to a closed position;

- figures 10 to 12 are enlarged scale views of the components illustrated in figures 8 and 9;

- figure 13 is a front view of the doors of the generating unit of figure 1; and

- figure 14 is a cross-sectional view taken along line XIV-XIV of figure

13.

In the accompanying drawings, identical parts or components are distinguished by the same reference numerals.

EMBODIMENTS OF THE INVENTION

With reference to the attached figures, a heat generating unit or stove 1 is shown, comprising a main frame 2 defining at least one combustion chamber 3, which generating unit 1 is advantageously arranged to be fed, preferably during different work cycles, with at least two different fuels, for example wood and pellet. In the combustion chamber 3 a brazier for the positioning and combustion of the fuel or fuels can clearly also be provided.

The unit 1 further comprises at least a first door or wing 4 for closing/opening a main window 5 for accessing to the combustion chamber 3, through which main window 5 a first fuel can be positioned in the combustion chamber 3, for example wood, in logs if desired.

The main window 5 is defined by the frame 2, in particular on a face, if desired on a front face of the generating unit 1. The main window 5 may have a rectangular, square, circular or another type configuration, for example.

The frame 2 can have a framework portion 2a for delimiting the main window 5.

The first door 4 is constrained, for example pivoted to the frame 2, if desired around a vertical, in use, axis. More particularly, the first door 4 can be pivoted at one of its edges to the frame 2, in particular at one corner, if desired, a front comer thereof.

The first door 4 can have a glass or a double-glazing unit 4a fitted in the main body of the door, designed to allow inspection of the combustion chamber 3. If desired, the first door 4 is also provided with an opening handle OH.

The first door 4 could comprise the main plate 4b with a raised portion 4c extending therefrom, which raised portion 4c may have a square, rectangular or circular-plan tubular configuration designed to be inserted, substantially to size within the framework portion 2a and therefore within the main window 5 for sealingly closing (if desired by means of a suitable gasket) the latter, while the main plate 4b in this closed position abuts against the framework portion 2a.

Moreover, the unit includes at least one tank 6 for containing the first fuel or a second fuel, for example pellet, as well as at least one second door or wing 7 for closing/opening an access and loading opening 8 of the containment tank 6 with the first or second fuel.

The containment tank 6 can be delimited by the frame 2 or better by walls of the frame 2 or it can be produced separately and then introduced into the main frame 2 and constrained to or bolted on it.

The containment tank 6 can be in position below or above the combustion chamber 3. In particular, according to the embodiment shown in the figures, the tank 6 is below or in a lower position than the combustion chamber 3.

Moreover, the access and loading opening 8 is defined by the frame 2, preferably on the same face, the front one if desired, of the generating unit 1 on which the main window 5 is defined. This means that the opening 8 is below the main window 5.

According to this embodiment, the second door 7 is constrained below the first door 4.

The second door 7 is constrained to the frame 2, for example pivoted, if desired, around a horizontal, in use, axis.

More particularly, the second door 7 can be pivoted or constrained angularly movable to the frame 2 so as to be movable between a first closing trim of the containment tank 6, if desired close to the frame 2, in which the second door 7 can have, for example a substantially vertical trim and a second opening trim of the respective tank 6.

If the tank 6 is below the combustion chamber 3, then when the second door 7 is in the second trim, it is possible to access the tank 6 from above and at least partly from the sides, if desired.

According to the non-limiting embodiment shown in the figures, the unit 1 can comprise support and pivoting means 14 of the second door 7.

If desired, the support and pivoting means 14 comprise a first rod element 14a, which can have a main section 14al pivoted, for example by means of first brackets 15a, to the frame 2, if desired around a horizontal axis, and two end sections 14a2 with end rotatably fitted in a respective section of the second door 7.

A second rod element 14b can then be provided beneath the first rod element 14a and designed to support the second door 7 when it is in the closed position. The second rod element 14b can have a main section 14b 1 pivoted, for example by means of second brackets 15b, to the frame 2, if desired around a horizontal axis, and two end sections 14b2 with ends, for example L-shaped ends, fixed in a respective section of the second door 7, for example at an edge, which is lower and external with respect to the unit 1, when the second door is in the closed position.

The second door 7 can be configured as a plate 7a with L-bent edges, in particular at the sides thereof.

Advantageously, the second door 7 can also have a grip handle component 7b in one piece or less with the plate 7a.

If desired, the grip component 7b is pivoted to the plate 7a around a horizontal axis and is angularly movable with respect to the plate 7a.

The grip component 7b can also have flanks 7c wrapping the plate 7a edges.

The flanks 7c of the grip component can have one or more shaped grooves or slots or eyelets 7d whose delimiting edge is designated to abut against a respective pin or pins 7e rising laterally from the plate 7a.

The unit 1 also includes means for feeding a comburent fluid, for example air, into the combustion chamber 3. Such feeding means can comprise specific ducts leading into the combustion chamber 3 as well as means for pushing or the like the comburent fluid, for example one or more fans.

Advantageously, a duct or chimney 16 for transporting the exhaust or combustion gases or fumes from the combustion chamber 3 towards the outside or towards a suitable discharge area is provided, as well as any refractory arranged behind and/or on the flanks of the combustion chamber 3.

Moreover, the generating unit 1 comprises locking/unlocking means 10 both of the first door 4 and of the second door 7, which locking/unlocking means 10 are movable or switchable between a first operating position and a second operating position. As regards first the first operating position, in the same (figures 8 to 12) the first door 4 is unlocked and therefore it is possible to move it (for example angularly around a vertical axis) with respect to the frame 2 to open the main window 5 to allow access to the combustion chamber 3, while the second door 7 is locked in the closed position of the access and loading opening 8 and cannot be moved from this latter position.

When the locking/unlocking means 10 are in the second operating position (figures 3 to 7) instead, the second door 7 is unlocked and therefore it is possible to move it with respect to the frame 2 and to the tank 6 (for example angularly around a horizontal axis) to open the access and loading opening 8 so as to allow access to the tank 6, while the first door 4 is locked in the closed position of the main window 5 and it is not possible to move it from the latter.

If desired, the locking/unlocking means 10 comprise at least one pin or plug or pawl 11a, l ib as well as means for moving the pin(s) 11a, l ib between the first and second positions, in the first position the pin 11a interferes with the second door 7 or with a portion thereof, while in the second position the pin 1 lb interferes with the first door 4 or with a portion thereof.

In the second position, the pin 1 lb can also interfere with a portion of the frame 2 and/or in the first position the pin 11a can interfere with another portion of the frame 2.

Advantageously, the movement means can comprise at least one electromagnet 12, in particular tubular or defining an axial light, as well as electronic feeding means 12a of the electromagnet designated to determine the activation or deactivation of the latter and therefore whether the at least one pin 1 la, 1 lb is attracted or not, so as to move it from the first to the second position or vice versa.

More particularly, the electromagnet 12 comprises a casing element, and then a stem element 11c is provided defining the pins or plugs or pawls 11a, l ib at the respective ends, which stem element 11c, if desired realized in a ferromagnetic material, is slidably mounted within the electromagnet 12. The stem element 11c can have a vertical main axis, while the pins 11a and 1 lb can constitute the upper and lower, respectively, ends of the stem element 11c.

With such a structure, the locking/unlocking means 10 or, if provided, the electronic feeding means 12a could be activated by pressing (for a few seconds, for example 2-3 seconds) a button on the generating unit 1 display, or by means of a radio control and in this case, the stem element 11c, once the electromagnet 12 is electronically powered, for example at 12V, would be attracted by the magnetic field thus generated and then lifted or lowered so that a pin 11a or l ib interferes with the first 4 or second 7 door or with a part thereof (as well, if desired, with respective parts of the frame 2), preventing the opening of the latter and unlocking instead the opening of the other door 7 or 4.

The electromagnet 12 can be electronically powered by means of a cable 12a or even with Wi-Fi or with another suitable mode.

As regards the engagement of the locking/unlocking means 10 with the first door 4, the latter can delimit at least one first hole or slot 4d for inserting/releasing a pin l ib, higher if desired. According to the non-limiting embodiment illustrated in the figures, the first hole or slot 4d is delimited at a bottom portion of the first door 4.

The locking/unlocking means 10 can be constrained to the frame 2. In this regard, if the locking/unlocking means 10 comprise an electromagnet 12, the same or the respective casing element could be fixed, for example welded, bolted, fitted within a component of the frame 2, if desired to the framework portion 2a of the same.

With reference to the engagement of the locking/unlocking means 10 with the first door 4, the latter or rather a respective portion or shaped sheet 4e constrained to the plate 4b can delimit at least one first hole or slot 4d for inserting/releasing a pin 1 lb, if desired a higher pin.

The frame 2 can instead delimit at least one second hole or slot 2b, if desired at the respective framework portion 2a for delimiting the main window 5 and in the second operating position, the or each first hole or slot 4d is aligned with a/the respective second hole or slot 2b, so that it is possible to insert a respective second pin l ib in these aligned holes and thus lock the first door 4 in position with respect to the frame 2.

According to the non-limiting embodiment shown in the figures, the electromagnet 12 is mounted under the framework portion 2a with a respective second pin 1 lb always inserted within the second hole or slot 2b, both in the first and in the second operating position. When the locking/unlocking means 10 are moved to the second operating position, with the first door 4 in the closed position, that is to say with respective raised portion 4c within the framework portion 2a and therefore within the main window 5, then the second pin l ib is moved (for example lifted) so as to insert it also in the first hole or slot 4d, thereby locking the first door 4 in position.

With respect to the engagement of the locking/unlocking means 10 with the second door 7, the latter can delimit a third hole or slot 7g for inserting/releasing a pin 11a, if desired lower. In this regard, the second door 7 can have a wing- shaped section 7f extending from one side of the second door 7, if desired from an upper portion thereof, which wing-shaped section 7f is suitably shaped or bent, if desired U-shaped, so as to delimit the third hole or slot 7g for inserting/releasing a pin 11a, if desired lower. The third hole or slot 7g can lead upwards and downwards, for example.

According to the non-limiting embodiment illustrated in the figures, when the locking/unlocking means 10 are moved to the first operating position, with the second door 7 in the closed position, i.e. close to or abutting against the frame 2 and/or against the edge of the tank 6 delimiting the access and loading opening 8, then the first pin 11a is moved (for example lowered) so as to be inserted in the third hole or slot 7g, thus locking the second door 7 in the closed position, preventing its opening as long as the locking/unlocking means 10 are not moved from the first operating position to the second operating position or to a possible intermediate position, for example. Clearly, the electromagnet 12, if provided, could also be mounted in a different manner, if desired, with a first pin 11a always mounted (both in the first and in the second operating position) in a hole of the frame 2, (similarly to what is now described for the second pin l ib), and the second pin l ib mounted as described above for the first pin 11a.

The unit 1 can then comprise at least one position sensor designed to detect whether the first door 4 and/or the second door 7 is opened or closed.

By way of example only, with the tank 6 under the combustion chamber 3, a solution could be provided wherein the stem element 11c is in a rest position in a lowered condition, in interference with or locking (for example as indicated above) the second door 7 and such that once the electromagnet 12 is driven, that is to say once the electrical communication between an electric source and the electromagnet 12 is activated (by pressing a button or by means of a radio control), lifting of the stem element 11c is determined by electromagnetic attraction and therefore the opening of the second door 7 of the tank 6, so that it is possible to open the second door 7 and load the tank 6 with a second fuel, such as pellet.

At the same time, by ascending the stem element 11c, the respective pin l ib physically interferes with the first door 4, inserting itself, for example, in a first hole or slot 4d, thereby locking and preventing the first door 4 from being opened.

In this case, once the second door 7 of the second fuel is closed, the electromagnet feeding could be interrupted, if desired incorporating a solenoid, following for example pressure by the second door 7 of a position sensor, such as a microswitch designated to check its position and accordingly inform a control unit.

When the electric power feeding of the electromagnet 12 is interrupted, the stem element 11c descends by gravity, locking again the second door 7 and unlocking instead the first door 4.

Moreover, if the first door 4 is open, a position sensor, such as a microswitch can ascertain the opening thereof and inhibit the possibility of activating the locking/unlocking means 10, for example the electromagnet.

The first operating position and the second operating position are preferably the only operating positions wherein the locking/unlocking means 10 can be positioned, although it is possible according to a variant that the same also present other operating positions, such as a simultaneous locking position of both doors 4, 7 and/or a simultaneous unlocking position of both doors 4, 7.

Clearly, different locking/unlocking means 10 can be provided, other than those illustrated above, which can be mechanically or electronically driven if desired.

If desired, the generating unit 1 is also provided with at least one feed duct 13 for the second fuel from the tank 6 to the combustion chamber 3 as well as automatic conveying means, such as a screw or similar, of the second fuel along the feed duct 13 up to the combustion chamber 3.

Naturally, the unit also comprises one or more driving motors, for example conveying means, as well as a control unit.

The unit can then be equipped with one or more probes for the exhaust gas temperature, based on which value(s), the control unit could decide to switch the operation of the stove from wood to pellet, suitably driving the locking/unlocking means and automatically loading the pellet from the tank 6 to the combustion chamber 3 or vice versa.

As it will be possible to ascertain, with a unit or stove according to the present invention it is not possible to simultaneously open the first door 4 and the second door 7.

This occurs thanks to the locking/unlocking means 10 designated to selectively lock the first door 4 or the second door 7.

This ensures, among the other things, that when the first door 4 is open, it is impossible to open the second door 7, so as to prevent embers or small flames from accidentally falling from the combustion chamber 3 into the tank 6, which would clearly result in an unwanted combustion of the pellet in the tank 6. Basically, the locking/unlocking means 10 would perform a fire risk limiting function for the tank 6, which is preferably under the combustion chamber 3.

Modifications and variants of the invention are possible within the scope defined by the claims.

Thus, for example, other fuels could be envisaged compared to wood and pellet.

Moreover, different constraints could also be provided for the doors or wings, as well as holes for the pin(s) 11a, l ib different as described and illustrated.