WO2014170814A1

WO2014170814A1 - A pellet oven

Info

Publication number: WO2014170814A1
Application number: PCT/IB2014/060703
Authority: WO
Inventors: Giovanni BERLINCIONI
Original assignee: Berlincioni Giovanni
Priority date: 2013-04-15
Filing date: 2014-04-14
Publication date: 2014-10-23
Also published as: ITFI20130082A1

Abstract

The present invention regards the field of devices for cooking foods indoors or outdoors, without requiring in any case connection to the electrical or gas network, and more precisely it regards a pellet-fed transportable oven, also adapted for use as a heater.

Description

TITLE

A PELLET OVEN

DESCRIPTION

Field of the invention

The present invention regards the field of devices for heat production, namely for cooking foods indoors or outdoors, without requiring in any case connection to the electrical or gas network, and more precisely it regards a new transportable pellet-fed oven, which can be efficiently used also as a heater.

Background of the invention

A number of devices and apparatus for cooking foods are known, including ovens and stoves of various configurations and types. However, as regards apparatus that can be transported and used outdoors, for example for typical barbeques, and more generally in the absence of a connection to the electrical or gas network, the state of the art known to the Applicant, except low capacity camping gas stoves, is actually limited to the so-called open flame barbeque stoves, fed by wood or charcoal. This type of apparatus, besides being averagely cumbersome and difficult to move, also implies considerable safety problems, besides producing fumes and pollutant combustion residues (in any case uncomfortable and/or difficult to dispose) and the ensuing maintenance difficulties.

Summary of the invention

The object of the present invention is to provide a new type of transportable oven operating without connection to the electrical or gas network, which besides being economic and easy to handle is also easy to manage, producing a low amount of fumes and residues, while simultaneously allowing an efficient and healthy cooking.

This and other objects are attained by the pellet-fed oven according to the present invention, the essential characteristics of which are defined by the first of the attached claims.

Further important characteristics are delineated by the dependent claims.

Brief description of the drawings

The characteristics and advantages of the pellet-fed oven according to the present invention shall be more apparent from the following description of embodiments thereof provided by way of non-limiting example with reference to the attached drawings wherein:

figure 1 is a front schematic view of an oven according to the invention, in exploded configuration;

- figure 2 and figure 3 are side views of the oven of figure 1 , again in exploded view, respectively according to arrows II and III;

figure 4 is a top plan view of the oven of the previous figures;

figures 5 and 6 still show the same oven, but in assembled or operating configuration, respectively in a front view and in a side view corresponding to that of figure 2;

figure 7 represents, again schematically, a different and simplified embodiment of the oven according to the invention, in side view and assembled or operating configuration; and;

figures 8 and 9 are respectively a side view according to arrow VIII, and a top plan view of the oven of figure 7.

Detailed description of the invention

With reference to figures 1 to 6, an oven according to the invention comprises at least one fuel chamber 1 , 2, adapted to receive the fuel (pellet fuel, i.e. solid biomass fuel in the form of small-sized cylinders or any other similar granular shape) and a fume evacuation chimney 3, spaced from each other. The fuel chamber or chambers 1 , 2 and the chimney 3 are joined and communicating, for the passage and the at least partial ignition of the gas produced by the fuel (as explained hereafter), through at least one cooking plate 4, 5 having a box-like structure.

In the illustrated embodiment two fuel chambers 1 , 2 are provided one adjacent to the other and communicating with the chimney 3 through two respective cooking (or generically heating) plates 4, 5 intended to receive food to be cooked, superimposed with respect to each other but separated by a compartment 6. The chambers 1 , 2 are tubular bodies, for example parallelepiped-shaped or cylindrical adapted to rest with a base which, along with the base of the chimney, defines a resting plane a of the oven. Such plane has in the normal configuration a horizontal configuration, hence the chambers rise vertically therefrom, staggered height-wise for connecting singularly and independently to the cooking plates 4, 5. Thus, the latter have a horizontal configuration parallel to the support plane (the lower plate being however raised with respect thereto), while the chimney 3 has in turn a tubular configuration as the fuel chambers, with a greater vertical elevation. Advantageously, like in the example, the chimney is obtained following the reversible mounting of a plurality of segments 31 - 3n (where n=4 in the example), of crosswise dimensions (diameter if cylindrical) which decrease progressively allowing a reversible coupling of telescopic type. Clearly, only the first segment 31 is integral with the plates while all the others may be mounted or demounted (but the telescopic arrangement can be carried out also via a retracting slidable connection that keeps all the segments linked with each other and compacted one inside each other in a closed configuration).

The fuel chambers 1 , 2 are preferably simple tubular elements opened both at the base and at the upper part. As a matter of fact, instead of being loose, the fuel is arranged in the closed chamber once enclosed in reticular bucket-like baskets 7, 8, indeed adapted to be fittingly inserted in the chambers. Such solution also facilitates the removing of the residue exhausted fuel. The baskets 7, 8 in turn have a tubular development around a central axis which, once a basket is inserted in the relevant chamber, is orthogonal to the support plane a and coincides with the central axis of the chamber.

However, the extension of the basket along such axis is lower than that of the chamber, hence, when the basket is inserted, gaps 11 , 21 becomes formed at the base of the chambers 1 , 2 (thus, below the part of the chamber which is actually occupied by the baskets). The gaps 11 , 12 are accessible through doors 12, 22 formed on a side wall of the chambers. In order to attain such result in a simple and functional manner the inserted baskets rest over the free top edge of the chambers, by means of hooking lips 71 , 81 which project crosswise from at least two opposite sides of the baskets, at a top edge thereof, for abutting on said edge of the chambers 1 , 2. Obviously, other types of solutions, such as the provision of perforated channels at suitable heights which support the baskets at their base and define the gaps by physically separating them from the area where the fuel is received, can also be adopted.

According to a preferred solution, each basket 7, 8 also features centrally, still with longitudinal development, a tubular core 72, 82, still of reticular and cylindrical structure in the illustrated example, which rises from the bottom of the basket and it is intended to remain empty, i.e. not filled with fuel.

The gaps 11 , 21 , as well as an analogous space 35 at the base of the chimney 3, accessible through a door 36, are adapted to receive firelighter means, i.e. products made to facilitate the ignition of fuels, generally based on kerosene or any other easily inflammable substances, of the type commonly used in heaters or barbeque ovens. While in the case of chambers 1 , 2, the function is that of actually triggering the combustion, as far as the chimney 3 is concerned the heat developed by the ignition of the firelighter has the effect of creating a convective flow which activates the drawing of the exhaust fumes by the chimney.

The plates 4, 5 have on a front side 4a, 5a, orthogonal to the support plane, and on the opposite side (not visible in the figures), an arrangement of air intake holes 41 , 51 which communicate their inner part with the environment (outside). On the chimney, above the communication port with the higher plate, a valve 37 is provided for regulating the discharge flow. This valve can be operated from the outside to control the working regime of the oven, and in particular the temperature reached by the plates.

Thus, the oven according to the invention works as follows. The baskets 7, 8 filled with fuel (pellets) are inserted into the respective fuel chambers 1 , 2. Then, the firelighter substances are ignited through the doors 12, 22. At the same time, through the door 36, the heating of the air within the chimney 3 is prompted. This priming action provided by the firelighter substances implies establishing a pellet carbonification process, due to the low presence of oxygen in the chambers. It is the same presence/filling of the pellet which reduces the amount of oxygen in the combustion environment, the sole significant supply of air thereto deriving from the empty space in the cores 72, 82. However, there cannot in principle be excluded the possibility of providing the chambers with reversible closing means of the top opening, for example rotatable doors.

The syngas generated by the carbonisation (so-called biomethane or green gas) is drawn inside the plates 4, 5 by the chimney effect, and passing through them is enriched of oxygen coming from the holes 41 , 51 ; this ignites the gas producing the heat required to allow cooking. By operating the valve 37 the flow of the syngas, and hence the passage of the flame in the plates, is blocked or let loose (respectively by closing or opening the passage), and this in turn corresponds to an increase or a reduction of the temperature of the plates, respectively.

This situation remains in a standard working condition until the fuel is exhausted. The few residue fumes are ejected from the chimney. The transient required to reach the maximum cooking temperature does not exceed five minutes, including mounting the chimney 3 which, as mentioned, preferably has a structure that can be assembled/disassembled into segments, so as to allow for a better transportation of the oven when not in use, rising the chimney only when required.

The many advantages of the oven, easily related to what has been explained above, include:

- the safety typical of this type of fuel, i.e. the pellet, which in case of an accidental overturning of the oven, contrary to wood, methane or oil derivates etc, extinguishes immediately thereafter thus also interrupting the generation of syngas; in addition, it should also be observed that the sole considerably hot parts of the entire structure are the plates 4, 5, in the inside of which the fire develops, while the fuel chambers and the chimney remain at temperatures well below incandescence;

- the minimum overall dimension, the ease of transportation as well as of installation, also indoors, being it sufficient a discharge for fumes and an opening for the reintegration of air in the environment, elements already present for example in any kitchen (as required by specific law provisions); from a dimensional point of view, it should be noticed that with a chimney slightly higher than one metre, and plates a few cm thick which develop for about 90 cm in length and 60 cm in width, an excellent operation is ensured with baskets 7, 8 of about one litre capacity;

- the extremely low fuel consumption; tests have shown that a basket having a capacity of about one litre of pellet allows the operation for about one and a half hour at an average temperature on the cooking plates of 160° C;

- the simplicity of use, given that the oven can be mounted and operated through few simple actions that can be easily performed by a user; - the versatility, considering that the oven can also be used as an efficient heater, besides as grills, oven and cooking appliance;

- the possibility of use anywhere even outdoors, in woods, camps, even in tents, campers, boats etc, given that the combustion occurs in closed chambers without open flame;

- the almost total absence of residues (ashes) after use, as observed following numerous tests.

The structure of the oven shall usually be made of metal material (namely aluminium) adapted to ensure suitable robustness and heat conductivity, though in principle it cannot be excluded the use of other materials, especially for the chimney and the fuel chambers where the heat conductivity is not a requirement. As mentioned, the geometry could be different for example from the one of the illustrated example, the sole structurally binding concept being at least one chimney and at least one fuel chamber (having sections of any shape) spaced apart by at least one cooking plate and communicating therethrough.

The previously described example, with two superimposed cooking plates, clearly allows the simultaneous cooking of several foods on a doubled cooking surface. However, the structure can be tripled, even though the most rational solution remains the two-plate solution. At most, with reference to figures 7 to 9, it is also conceivable to provide a simplified embodiment provided with a single plate and thus a single fuel chamber. There is no need for a detailed description of such embodiment, the characteristics of which are immediately apparent from the drawings, in which reference numbers corresponding (in the order of hundreds) to those of the first embodiment, are used for practically identical parts.

A remark is due only as far as the position of t e regulation valve is concerned, that in this case follows an alternative solution with respect to that of the first embodiment. Indeed, the valve indicated with 142 is arranged on the plate immediately before the connection with the chimney, instead of on the chimney itself. This solution may clearly be implemented also in the first embodiment, with two valves independently and selectively regulating the flow in both plates.

On a different note, there cannot be excluded even a hybrid embodiment with two or more cooking plates but only one fuel chamber which feeds both of them.

The oven according to the invention, and namely the plate or plates, can be integrated with a hydraulic circuit (comprising e.g. a coil that is extensively spread over the plate or plates, at the inside or the outside of the same), so that the oven has even the function of a boiler, as can be obviously implemented by a skilled person. The hot water or even steam so produced can be used for sanitary purposes, (by means of accumulation in a tank possibly provided in turn with a heating device for keeping the water at the desired temperature) or to feed an electric power generating system (possibly by making use of a set of ovens arranged in parallel)

On the other hand, even in the basic configuration described above, as already mentioned, the oven can be used, instead of for cooking purposes, for heating the surrounding environment. For the cooking use, the plate or plates can be shaped like a tray, that is with a slightly raised peripheral edge so as to avoid the dispersion of the liquids or fats produced during cooking. Such a raised edge can possibly be broken by a channel for easily draining and collecting the above cooking residues.

Up to now, the present invention has been described with reference to the preferred embodiments thereof. It should be observed that there can be other embodiments referring to the same inventive concept, all falling within the scope of protection of the claims that follow.

Claims

1. A transportable oven comprising: at least one fuel chamber (1 , 2) adapted to contain a granular compressed biomass fuel, said chamber being provided with a support base and an opening for filling the chamber with said biomass fuel; a fume evacuation chimney (3) having in turn a support base, the support bases of said chimney (3) and of said at least one chamber (1 , 2) defining a common support plane; at least one heating plate (4, 5) having a box-like structure spaced and parallel with said support plane, extending between said chimney and respective of said at least one chamber (1 , 2) so as to put them into internal communication, the at least one plate being provided with air intake holes (41 , 51 ); wherein inside said chimney (3) and said at least one chamber (1 , 2), adjacent with the support bases and below said at least one plate, respective spaces or gaps are formed (11 , 21 , 35) accessible from the outside for the insertion of fire starter lighter means.

2. The oven according to claim 1 , wherein said chimney (3) and said at least one chamber (1 , 2) have a tubular structure with axis orthogonal with said support plane, said basis being at longitudinal ends of the structure, in said at least one chamber the opening for filling the chamber with the biomass fuel being formed at the opposite longitudinal end.

3. The oven according to claim 1 o 2, wherein said chimney (3) has a decomposable arrangement comprising a number of consecutive segments with mutual locking of a releasable type.

4. The oven according to any of the previous claims, wherein said at least one plate has a front side (4a, 5a) and a rear side orthogonal with said support plane and in which said air intake holes (41 , 51) are formed.

5. The oven according to any of the previous claims, comprising valve means (37, 142) adapted to be controlled from the outside and to selectively shut the passage of the gas downstream of said at least one plate (4, 5).

6. The oven according to claim 5, wherein said valve means comprise a valve associated to said chimney, above said at least one plate (4, 5).

7. The oven according to claim 5, wherein said valve means comprise a valve associated to each of said at least one plate (4, 5), immediately upstream of the junction with said chimney .

8. The oven according to any of the previous claims, comprising for each fuel chamber (1 , 2) an extractable net-like basket (7, 8) for containing the fuel, having an elongated development orthogonally with said support plane.

9. The oven according to claim 8, wherein said basket comprises hooking means (71 , 81 ) adapted to abut with the respective chamber to keep the basket in a suspended arrangement that defines at a lower side said gap (11 , 21 ).

10. The oven according to claim 8 or 9, wherein said basket comprises a tubular core (72, 82) still in a net like material, adapted to remain unfilled by said fuel.

11. The oven according to any of the previous claims, comprising two heating plates (4, 5) mutually parallel and spaced by a compartment (6), two fuel chambers (1 , 2) being provided, independently communicating with said plates and mutually staggered in height with respect to said support plane.

12. The oven according to any of the previous claims, wherein said gaps (11 , 21 , 35) for the fire starter lighter means are accessible through respective doors (12, 24,

36) formed in side walls of said at least one chamber and of said chimney.

13. The oven according to any of the previous claims, wherein said plate or plates (4, 5) are integrated with a hydraulic circuit, whereby the oven is adapted to work as a boiler.

14. The oven according to any of the previous claims, wherein said plate or plates (4, 5) are shaped with a raised peripheral edge so as to prevent the dispersion of cooking liquids or fats.

15. The oven according to claim 14, wherein said raised edge is cut by a channel for draining said cooking liquids or fats.