EP3936764A1

EP3936764A1 - Pellet combustion heater with self-regulating automatic reload

Info

Publication number: EP3936764A1
Application number: EP21158740.7A
Authority: EP
Inventors: Ruben Rodolfo Salvador Rapetti
Original assignee: R & R Exhibidores SA
Current assignee: R & R Exhibidores SA
Priority date: 2020-07-08
Filing date: 2021-02-23
Publication date: 2022-01-12
Also published as: AR119384A1

Abstract

The invention refers to a heater of the type developed to heat open or semi-closed spaces, using pellets as fuel material and carrying out progressive combustion, where the pellets enter the combustion chamber gradually, as combustion proceeds. The pellet-containing tank is adjacent to the main body of the heater and has a load opening that communicates with an internal hopper which discharges into a feed conduct arranged in an inclined plane and extending to the internal combustion chamber defined inside said main body. The main body is of a quadrangular section, with a closed lower section, which walls define passages for the inlet of primary and secondary air, and an upper section mesh wall inside which a transparent tube is coaxially arranged to contain the flame formed with flat glass-ceramic plates, one of which is an access door for cleaning. It is to be noted that the base of the combustion chamber is a wire mesh. Likewise, the lower section of the main body includes an upward air passage (F1) through its longitudinal axis, combined with a peripheral ascending air passage (F2) defined in the walls, combined with a direct transversely oriented air inlet (F3) that is consistent with the burner, combined with a transversal inlet of secondary air (F4) that originated in the fuel tank walls.

Description

Scope of the Invention

The present invention, for which patent is sought, is mainly related to a PELLET COMBUSTION HEATER WITH AUTOMATIC SELF-REGULATING RELOAD, suitable for use in external and semi-covered environments, and characterized by a new constructive concept on which basis operation thereof is advantageous over heaters presently known.
More specifically, the present invention relates to a heater of the type developed for heating open or semi-closed spaces.
The inventive heater is particularly designed for using pellets as fuel material, with a consumption of about 2.00 kg/hour, so that it can operate autonomously for 5 hours or unlimited time without the need of reloading to switch it off. It does not use electricity or gas, which provides great security for use. It does not require the use of an air shaft and does not produce unpleasant odors. The present invention is highly suitable for terraces and open areas of rural houses, bars, hotels, restaurants, accommodation, etc. in addition to private homes.
The heater of this invention is mainly characterized in that it carries out progressive combustion, where the pellets enter the combustion chamber gradually, that is, the new pellets enter as the combustion proceeds, thereby ensuring a continuous heat exchange.
The inventive heater is characterized by the fact that the said automatic fuel feed is produced by the action of its weight, without feeders or drivers of any kind. This is possible because the pellet container is a hopper with a tapering section adjacent located to the body of the heater and communicates with the combustion chamber through an inclined ramp at an angle of between 40° and 60° approximately.
To produce the desired regulated combustion, the inventive heater has a wire base that retains the pellets that fall on the said ramp and at the same time allows enough oxygen to pass through to ensure combustion.
The importance of this wire mesh is to be noted since it regulates the inlet of new pellets into the combustion chamber. The size of the wire mesh openings must be sufficient to maintain an acceptable fire level, and not so high as to switch off the stove.
It is to be noted that said pellet feed hopper adjacent to the heater body, allows the user to refuel the equipment while it is in operation, this being an essential difference in use over the current state of the art.
Likewise, due to the particular constructive concept of the inventive heater, the air inlet that supplies oxygen for combustion, is located such that the normal ambient conditions outside (winds, etc.) do not affect its operation. The arrangement and structure of the secondary air input are of essential importance and are also protected from the outside.
The present invention defines a new combination of means conceived to achieve a superior result, the same being unexpected and novel for an expert in the art. Consequently, apart from its novel features, its constructive and functional concept discloses a clear inventive step, so that the present invention complies with the legal requirements to be considered a patentable invention.

Prior Art

The prior art includes pyrolytic combustion heaters, which operate with biomass energy, a type of renewable energy from the use of organic and industrial matter formed in some biological or mechanical process, such as wood, sawdust, peanut shells, among others. This is a cheap heating arrangement that uses a renewable fuel made from plant waste.
Indeed, as already known, pellets are a totally natural product, classified as solid biomass, which is made up of very small cylinders, a few millimeters in diameter. They are made from the dry natural sawdust, without any additives, which is compressed to a high pressure to form the pellet, which makes them have a very dense and hard composition and, consequently, a highly calorific power.
These pellets are easily transported, have a highly energetic performance, allow temperature regulation, and are environmentally friendly because they do not generate carbon monoxide. As a result of said high performance, the fumes are not visible and have a very low particle emission.
Traditional pyrolytic stoves have a double-bottom container with walls having multiple holes, which receives the pellets that are used entirely as fuel. Pellets are loaded manually from outside.
For operation, combustion is carried out gradually from the surface exposed to oxygen that is provided with the inlet of air from the outside.
This perforated container is arranged on a carrier through which it is entered or removed from the lower sector of the heater body. When the container is removed, there appears an ash dump which arrangement is consistent with the bottom of the heater.
Outdoor pellet combustion heaters presently in the market, invariably use an operating principle commonly referred to as "pyrolytic", which is conducted by using a double-bottom container with an air chamber, which contains up to 7 kg of pellets, which are lighted and the flame is very gradually increased.
In general, with a full load, they only achieve 2 hours of autonomy, it is impossible to reload them, and also the flame generated does not reach 30 cm in height and is very irregular because the more the container is filled with pellets, the flame becomes shorter and the radiated caloric power is lower.
This is the first disadvantage encountered by known heaters. Indeed, in order to refuel the heater, it is necessary to wait until the burner cools down, which takes quite a long time because it cools down slowly until reaching ambient temperature.
Furthermore, in all cases, to remove the carrier that holds the container that receives the pellets, it is necessary first to remove the burner, which requires ample maneuvering space.
It is clear that in these known heaters, loading is carried out only once. Reloading is not possible at high temperatures.
They have been found to invariably include a transparent cylindrical tube with a circular section (generally made of borosilicate) through which the combustion flame is projected. This causes the first drawback since, for maintenance cleaning, it must be removed from the body of the stove, which requires waiting for it to cool and extremely careful handling because it is very fragile. A break means the replacement of the complete glass. It is to be also noted that in general said heater does not resist a sudden change in temperature such as by contact with rain outside.

Brief Description of the Invention - Advantages

The pellet combustion heater referred to in the present invention clearly overcomes the drawbacks pointed out because it comprises a novel operating principle that consists of establishing a continuous feed of combustible material (pellets) oriented towards a combustion chamber inside the heater body.
In this way, it is possible to regulate a constant flame of a very good dimension, as well as to allow the reload of combustible material even when the heater is in operation.
To that effect, the inventive heater is characterized by comprising a pellet tank adjacent to the heater body, with the particularity that it is of a shape such as a hopper having a tapping section, which unloads in a feed conduit extending to the combustion chamber, thereby defining an inclined plane, which inclination can be set from 40° to 60°, approximately.
Considering the said operation principle, the inventive heater may comprise a vertical body with a quadrangular section, with a closed lower section, which includes walls with holes that define the inlet of primary and secondary air, necessary for constant combustion without alterations, and an upper section of mesh walls inside which a transparent tube is erected to contain the flame and made up of flat glass-ceramic walls, where one of which acts as an access door for cleaning purposes.
Clearly, as a consequence of the constructive conditions briefly stated in the preceding paragraphs, a heater is produced, which can be reloaded while in operation. This is a huge advantage, especially when it comes to being outside in commercial premises.
Pellet reloading is performed from the upper part by removing the tank cover so that this task requires little space and loading is much safer for both the operator and the people around.
The aforementioned tube where the fire is channeled is arranged within a central metal structure, covered by four transparent glass-ceramic plates that make up four faces, one of which is hinged to function as an access door so that it can be cleaned without removing the tube.
This constructive condition provides notable advantages such as

ease of cleaning,
safety,
secured resistance to thermal shock by the use of glass-ceramic plates.

It is also noted that the lower body of the heater defines a space for the ash dump arranged in a position to allow its removal without affecting the overall operation of the arrangement.
The lighting of the stove is very simple, only with two caps of alcohol, and the amount of smoke generated is very low.
The pellets are burned gradually, not entirely like the pyrolytic ones, which ensures that the fire and heat they deliver are always uniform and even. In other words, it is safer and more efficient. On the other hand, the amount of smoke generated is very low.
This novel operating principle also ensures that the stove shutdown time can be regulated with high precision since it depends on the material remaining in the hopper.

Inventive Activity

No single heater that is currently known discloses or even suggests, the constructive solution that arises from what is indicated in the preceding paragraphs, and for that reason, the proposed heater, in addition to being novel, involves a clear inventive activity.

Brief Description of Drawings

To specify the advantages briefly described, to which users and experts in the art will be able to add many others and to facilitate the understanding of the constructive, constitutive, and functional characteristics of the inventive heater, a preferred example of an embodiment is described, which is illustrated, schematically and without a specific scale, in the attached drawings, expressly stating that, as an example, the same will have no restrictive or exclusive character concerning the scope of the present invention, but it is merely intended for explanatory and illustrative purposes.

Figure 1 is a perspective view showing the general exterior appearance of the heater of this invention.
Figure 2 is a perspective view of a partial section along a vertical plane of the same heater as the previous figure.
Figure 3 is also a vertical partial section view of the same heater rotated 90° concerning the previous figure.
Figure 4 is a vertical section view of the same heater as the previous figures.
Figure 5 is a perspective view showing a constructive variant of the same heater of this invention.
Figure 6 is a vertical section view of the same heater represented in the previous figure.

It is clear that, in all the figures, the same or equivalent parts or constituent elements of the arrangement correspond to the same reference numbers and letters, according to the example chosen for the present description of the inventive heater.

Detailed Description of a Preferred Example

As shown in Figure 1, the pellet combustion heater referred to in the present invention comprises a main body (E) with a quadrangular plan and high height that has a closed lower section (1) and an upper section mesh (2) that ends in an open upper end where a cap (3) is located that allows the exit of fumes.
It can be seen that said upper section mesh (2) encloses the referred transparent tube (T) channeling the flame that is generated.
As shown in the first four figures, the heater of this invention is distinguished by the fact that adjacent to said body (E), the tank (D) of solid fuel material, in this case, "pellets", is arranged with its corresponding upper cover (4) that closes the load opening.
With reference now to Figures 2, 3, and 4, the referred adjacent arrangement of the tank (D) is the one that establishes the basic constructive condition that allows the inventive heater to operate according to the aforementioned novel operating principle.
To that end, the aforementioned upper load opening of the tank (D) communicates with a new internal feed hopper (A) which, being tapered, discharges into an inclined plane ramp (5) that extends to the interior of the main body (E) to communicate with the internal combustion chamber (6).
The fuel material that enters, falling by its own weight, towards said combustion chamber (6) and is distributed on a V-shaped base (7) with a wire mesh wall, or an equivalent structure retaining the pallets and allowing the passage of oxygen required for combustion.
Particularly Figure 2 shows the location of the burner (8), as well as the presence of an ash dump (9), arranged below and which can be removed by a gate defined in said lower section (1) of the main body.
With reference now to Figures 3 and 4, the air inlet through the interior of the walls of the main body is shown by the arrows (F₁) of the central inlet and the arrows (F₂) of the peripheral inlet, which are associated with the air direct inlet (F₃) (shown in Figure 2) produced from the said tank (D), as well as the secondary air stream (F₄) (shown in Figure 6).
Figures 5 and 6 show that the same operating principle can be put into practice with a deposit of solid material shaped like a hopper (V) that acts as the referred internal hopper (A) shown in Figure 2.
Figure 5 shows the external appearance of this second version of the inventive heater, with an upper cover (10) that closes the load opening of the hopper (V).
Figure 6 shows how the pellets fall directed inside the inclined ramp (5) to communicate with the combustion chamber, where the wire mesh base (7) and the direct air inlet (F₃ ), combined with the peripheral air inlet (F₂) and secondary air inlet (F₄).

Claims

PELLET COMBUSTION HEATER WITH AUTOMATIC SELF-ADJUSTABLE RELOAD of the type developed to heat open or semi-closed spaces, using pellets as fuel material and carrying out progressive combustion, where the pellets enter the combustion chamber gradually as combustion proceeds, characterized in that a tank containing the pellets is adjacent to the main body of the heater and has a load opening communicating with a hopper inside which discharges into a feed conduct arranged in an inclined plane and extends to the internal combustion chamber defined inside said main body.
PELLET COMBUSTION HEATER, according to claim 1, characterized in that the main body is of a quadrangular section with a closed lower section, which walls define passages for the inlet of primary and secondary air, and upper section mesh walls inside which a transparent tube is erected coaxially to contain the flame.
PELLET COMBUSTION HEATER, according to claim 2, characterized in that the transparent tube to contain the flame has a quadrangular section, made up of flat glass-ceramic plates, one of which is an access door for cleaning.
PELLET COMBUSTION HEATER, according to claim 1, characterized in that the load opening is arranged on an inclined plane with an inclination angle of between 40° and 60°.
PELLET COMBUSTION HEATER, according to claim 1, characterized in that the base of the combustion chamber is a wire mesh.
PELLET COMBUSTION HEATER, according to claim 5, characterized in that the base of the combustion chamber is V-shaped and has a wire mesh wall.
PELLET COMBUSTION HEATER, according to claim 1, characterized in that the lower section of the main body includes an air passage upward (F1) along its longitudinal axis, combined with the passage of upward peripheral air (F2) defined by the walls, combined with a direct transversely oriented air inlet (F3) that is consistent with the burner, and combined with a secondary transverse inlet (F4) that originates in the fuel tank walls.
PELLET COMBUSTION HEATER, according to claim 1, characterized in that the pellet container tank is a hopper.