FIRE COLUMN

Description

[0001] The invention relates to a column of fire, in particular for the formation of a vortex flame.

[0002] In such fire columns, usually with a glass cylinder as an outer casing, the flame is set in motion by swirling air, creating a tornado-like appearance that is particularly captivating for viewers. US Patent 7,097,448 describes this flame pattern as "corkscrew-shaped." When using bioethanol and similar fuels, such fire or flame columns are also suitable for use in homes and serve primarily as decoration, but also for the relaxation of the residents, much like open fireplaces (or simulated fireplaces on monitors). Furthermore, such fire columns are used outdoors, for example on patios, where they serve as a source of light and warmth on cooler evenings.

[0003] A fire column of this type is known from US 8,641,413, in which a base of the same diameter is arranged at the lower end of the glass cylinder. A multitude of blade-guide elements are arranged helically or spirally within this base. Figure 8 illustrates the air inflow and turbulent flame zone. The glass cylinder rests on the base (as in US 2014 / 0290643 A1) and can therefore be easily knocked over, for example, by playing children. The risk of accidents and injuries is thus considerable, especially since the outer shell, which begins at the level of the combustion chamber, can become relatively hot. In US 2014 / 0290643, a second concentric glass cylinder was used for this purpose, but this significantly increased the construction effort.

[0004] The construction effort for the US 8,641,413 is also relatively high, as the individually attached guide elements are joined together with a metal ring. Furthermore, this guide assembly is divided into two parts so that one half can be swung out to provide access to the combustion chamber, for example, when lighting or extinguishing the flame. This is also due to the fact that the glass cylinder is relatively hot, so it should only be removed while wearing gloves. In the US 7,097,448, the outer casing is designed to remain relatively cool thanks to several tangential inlet slots; however, in this case, the casing is at least two parts and therefore relatively complex to manufacture and assemble.

[0005] US 2013 / 0011800 A1 reveals a column of fire composed of numerous parts. The construction effort is therefore relatively high.

[0006] The invention therefore aims to improve such a fire column with regard to safety and construction effort. This objective is achieved by a fire column according to claim 1. Advantageous embodiments are the subject of the dependent claims.

[0007] By fitting the outer shell over the guide elements, a secure hold is achieved because the inner wall of the outer shell grips the guide elements with a tight fit. This axial overlap preferably amounts to approximately 20% of the outer shell's height, so that, in combination with a relatively solid base or foot, unintentional tipping of the glass cylinder is virtually impossible. A further advantage of this overlap is that the outer edges of the guide elements are enclosed by the outer shell, eliminating the need for a separate component to define the individual air channels between the guide elements. The tight fit thus largely prevents the passage of supply air from one air channel to an adjacent one, while still allowing for slight, vertical lifting of the outer shell. This is advantageous because the numerous air channels (e.g.,The increased flow rate (with six guide elements) cools the outer casing (especially the inner wall of the glass cylinder), so that the lower part of the glass cylinder (and possibly the middle part at the level of the flame exit above the fuel container) remains relatively cool. This minimizes the risk of burns, and the outer casing can be removed by grasping the lower, cool area, even without gloves, to extinguish the flame.

[0008] This creates a chimney effect not only in the upper part of the fire column due to thermal updrafts, but also in the individual air channels between the guide elements. These can also be designed in a nozzle-like shape to increase the flow velocity for cooling purposes. A blower or fan (as in the aforementioned state of the art) is therefore unnecessary, which further reduces construction effort and increases its suitability for outdoor use. Furthermore, the guide elements can be manufactured cost-effectively as a single casting together with the base (including the fuel chamber), and the guide elements can also be produced in a single manufacturing step in angled or helical shapes to favor the formation of air vortices. With axial primary orientation of the guide vanes, they can also be extruded together with the fuel chamber in a manner similar to a heat sink tube, which can significantly reduce manufacturing costs (for higher production volumes).Furthermore, such extruded or cast parts exhibit high dimensional accuracy, which ensures the aforementioned clearance fit even without machining.

[0009] The generation of an air vortex rotating around the vertical axis of the fire column is particularly intense due to the aforementioned helical air guide elements. However, even with only slightly inclined blade surfaces, intense turbulence is achieved, as the initially axial, largely laminar airflow becomes increasingly turbulent in the area of ​​the flame. Even with a purely axial airflow from the lower part of the fire column, this chimney effect (with good cooling of the lower area of ​​the inner wall of the fire column) allows for turbulence resembling a flickering fire at flame level. Since the flame pattern also depends on the amount of air supplied, the lower air intake cross-section (before entering the guide elements) is preferably adjustable.

[0010] The outer casing is preferably made of refractory glass, particularly in the form of a cylinder with an open end. Such tubes can be manufactured with high precision (to ensure the aforementioned clearance fit) and are relatively inexpensive due to mass production (e.g., for use in the chemical industry). However, other shapes and materials are also possible, such as a metal tube with windows resembling a lamp, or a metal grid or mesh. The outer casing preferably rests at its lower end on several radially oriented pins attached to a base that surrounds the fuel container. This base can also be designed for fuel paste or for holding wood pellets or other fuels.

[0011] The base is preferably made of metal to ensure the necessary stability, especially in the design as a so-called tabletop fire, in conjunction with a relatively heavy base plate. The fire column can also be positioned higher to enhance the lighting effect, particularly with a bracket similar to a patio heater for terraces or with a support, e.g., a ground spike for gardens. The aforementioned pins can also be molded or attached to the lower end of, for example, the three guide elements, further reducing the number of components. The pins can be height-adjustable to regulate the airflow cross-section, particularly by being designed as eccentric pins, thus allowing the flame pattern to be varied. The outer casing can also be corrugated or stepped at the lower end to regulate the air gap by twisting it around its vertical axis.Perforated discs in a horizontal orientation or perforated rings that can be rotated against each other are also conceivable in order to regulate the air supply, or to smother the fire in the fire column when the slots provided in them are closed.

[0012] Several embodiments are explained below with reference to the drawings.

[0013] This shows: Fig. 1 a column of fire in cross-section; Fig. 2 (a) und (b) Each fire column is of an elevated design; Fig. 3 a column of fire according to Fig. 1 in perspective view; Fig. 4 (a) und (b) Each a sectional view with various guide elements; and Fig. 5 (a) und (b) One version of a fuel container for pellets each.

[0014] In Fig. 1 A fire column 1 is shown with a base part 2, which includes a fuel container 2a and a base plate 2b. Several guide elements 3 are arranged on the base part 2; these are designed here as helical sheets to generate an air vortex in an outer shell 4 placed over it. This outer shell is preferably designed as a transparent glass cylinder, thus allowing a view of the base part 2. The flame, enclosed around its circumference by the outer shell 4, is fed by fuel (of any consistency is possible), in particular bioethanol or fuel paste, from the (recessed) fuel container 2a and receives the required amount of air via an air inlet 6 (in the form of an annular gap) in the lower region of the fire column 1, more precisely at the lower, open end of the outer shell 4.

[0015] The incoming air is deflected by the guide elements 3 into a vortex or swirling flow. The air volume can be varied via the cross-section of the air inlet 6, for example by adjusting the height of the pins 5. In the setting shown here, the cross-section above the base plate 2b corresponds approximately to the passage volume between the base part 2 and the outer shell 4, with the relatively thin guide elements 3 hardly reducing the passage. The outer shell 4, which rests on the pins 5 (here three of them spaced 120° apart around the circumference of the base part), is fitted tightly or with a slight clearance over the guide elements 3 and contacts them at least in some places.

[0016] In Fig. 2 The fire column 1 is shown in an elevated version, namely in Fig, 2a with a frame-like support 2c, for example to be set up on a terrace. In Fig. 2b The support 2c is designed in a rod- or spike-like shape in order to be anchored in the garden soil with this holder in the manner of a ground spike.

[0017] In Fig. 3 is the column of fire according to Fig. 1 The perspective view clearly shows the helical course of the guide elements 3, as well as the upper opening in the base part 2, which forms a fuel reservoir 2a. The flame, schematically indicated, rises through the targeted air vortices, rotating or at least flickering within the glass cylinder 4. The achievable height, e.g., up to ¾ of the outer shell 4, can be adjusted primarily by the combustion behavior of the fuel (preferably ethanol) and by the air supply.

[0018] The following described Figuren 4a und 4b These are not representations of the invention.

[0019] In Fig. 4 Two side views of the base part 2 are shown, each featuring four guide elements 3, thus with a 90° division. The guide elements 3 are largely aligned axially (towards the vertical axis) and have an upwardly widening shape in order to form four nozzle channels around the circumference of the base part 2 and to accelerate the supply air from the opening 6. Fig. 4a The outer shell 4 is fitted tightly over the guide elements 3, so that their outer edges 3a almost touch the inner wall of the outer shell. To facilitate fitting despite this tight fit, the inner edge 4' is preferably ground conically, so that the outer shell 4 can be placed in a self-centering manner and then supported on the pins 5. The pins 5 are integrally molded to the lower end of the guide elements 3, in particular cast in one piece.

[0020] In Fig. 4b The guide elements 3 are inclined to the vertical axis indicated by the dashed line and have thin extensions 3' in the form of so-called winglets. These can be easily glued or soldered onto the guide elements 3 to increase turbulence. The pins 5 are attached separately from the guide elements 3 to the base part, preferably by means of eccentric bushings 5', in order to vary the height of the glass cylinder 4 and the inlet air cross-section relative to the base plate 2b.

[0021] In Fig. 5a The fire column is designed for the combustion of wood pellets, employing the principle of a wood gasifier. For this purpose, a perforated plate 7 is inserted in the lower section of the fuel container 2a, beneath which several air intake openings 8 (here in the form of perforations or slots) are provided. Primary air flows through these openings into the fuel container 2a below the pins 5 and through the pellets piled on the perforated plate 7 (not shown here, as this is a common fuel for operating pellet stoves). The air intake openings 8 can also be located in the base plate 2b, ensuring that the pellets in the fuel container 2a are evenly circulated and the desired wood gas is produced through pyrolysis (substoichiometric partial combustion).This is mixed at the upper end of the fuel container 2a with the secondary air swirled over the guide elements 3 and then burns (depending on the air supply) with a low or high flame. The air supply is controlled by (ring) slides (not shown) at the air inlet openings 8 (or also 6 and / or 8'). Fig. 5b ) adjustable.

[0022] To keep the flame centered, the fuel container 2a has a hood or partial cover 9 that is open in the center and is shaped in a roof-like or truncated cone-like form. This can also extend beyond the upper edge of the fuel container 2a, as indicated by the dashed lines, to allow an inward air supply via upper air inlets 8'. These are also more pronounced in the design shown. Fig. 5bThe air intake is provided in a ring-shaped configuration in the upper region of the fuel container 2a, the fuel container 2a preferably being double-walled around its circumference. This directs a partial airflow upwards along the circumferential surface, before being guided radially inwards into the combustion zone. This results in effective and relatively clean combustion of the pellets, as the hood 9 in particular stabilizes the flame.

[0023] In summary, the small number of components results in a minimalist design at low manufacturing costs. The robust construction enhances safety and simplifies operation. Furthermore, various versions are available for outdoor use, allowing for adjustments to either light output or heat output, particularly when using wood pellets. Indoor use as a "tabletop fire" is also possible, as bioethanol burns largely odorless and soot-free, a process further aided by the swirling flame.

Claims

1. Fire column the flame of which is fed by a fuel container, in particular for bio-ethanol, with an outer casing surrounding the flame of the fire column, with a base part (2) comprising the fuel container (2a), with guide elements (3) arranged on the base part, wherein supply air can flow in largely axially in the lower region of the outer casing via the guide elements (3) and be set into a helical rotation to form a vortex flame, wherein the outer casing (4) is placed over the guide elements (3), characterized in that the guide elements (3) are metal sheets that extend helically over half the circumference of the base part (2) of the fire column.

2. Fire column according to the preceding claim, characterized in that there are only three guide elements (3) offset by 120° and the outer casing (4) is designed as a one-piece glass cylinder.