Table oven

Abstract

Table-top furnace (1) with a furnace body (2) having an upwardly open combustion chamber (10) for burning a fuel, wherein the furnace body (2) has an outer wall (5), an inner wall (7), an outer base (6) and an inner base (8), and wherein the inner wall (7) and the inner base (8) delimit the combustion chamber (10), wherein the outer base (6) and the inner base (8) are arranged at a distance from one another via a first cavity (11), wherein a fuel support (3) is arranged in the combustion chamber (10) for supporting the fuel intended for combustion on the fuel support (3), and the fuel support (3) divides the combustion chamber (10) into a lower section (23) and an upper section (24), wherein the furnace body (2) has a first air passage opening (13) for the inflow of air into the first cavity, wherein a second air passage opening (14) is formed in the inner base (8) for air to flow through from the first cavity (11) into the lower section (23) of the combustion chamber (10), wherein at least one third air passage opening (16) is formed in the fuel support (3) for the flow of air from the lower section (23) into the upper section (24) of the combustion chamber (10), characterized in that the fuel support (3) has a closed partial surface (15) and the closed partial surface (15) is arranged above the second air passage opening (14) and that the closed partial surface (15) completely covers the second air passage opening (14).

Description

The invention relates to a table furnace.It is known to use ovens, in particular table ovens, for producing a special or pleasant ambient. Sometimes ovens, in particular table ovens, are also used for grilling or roasting, in particular smaller foods, such as marshmallows or the like.Furnaces or table furnaces frequently have problems with regard to incomplete combustion of the fuel, which can lead to the formation of harmful carbon monoxide, and with regard to the risk of contamination by the ash formed in the combustion. In particular when used in an interior, this can lead to considerable health risks or even risk of life or there is a risk of undesired soiling of the room.From WO 2022 / 169543 A1, for example, a furnace with a removable grate and a removable ash tray is known. The arrangement of the individual elements of the furnace disclosed therein, however, offers several disadvantages, in particular with regard to the supply of air to the combustion chamber and, in this respect, oxygen for the combustion of a combustible in the combustion chamber. There is then in particular the risk of incomplete combustion of the fuel with formation of carbon monoxide. This is primarily due to the provided concept for guiding the air flow through the furnace into the combustion chamber, which results, among other things, in particular from the provided ash shell past which the air must be guided.In this respect, there is a need to provide a table furnace which can be operated not only "cleanly" with respect to the ash formed, i.e. as far as possible without ash exiting, but also ensures complete combustion of the fuel, so that in particular the formation of carbon monoxide can be prevented as completely as possible.This object is achieved by a table furnace according to claim 1.A table furnace according to the invention has a furnace body which has a combustion chamber open at the top for burning off a fuel. The furnace body further includes an outer wall, an inner wall, an outer bottom, and an inner bottom. The inner wall and the inner bottom delimit the combustion chamber and the outer and the inner bottom are arranged spaced apart from one another via a first cavity. A fuel support is arranged in the combustion chamber, which serves for supporting the fuel provided for combustion on the fuel support. The fuel overlay also divides the combustor into a lower portion and an upper portion.The furnace body has a first air passage opening for flowing air into the first cavity. In the inner bottom, a second air passage opening for flowing air from the first cavity into the lower portion of the combustion chamber is also formed. In addition, at least one third air passage opening is formed in the fuel support for the flow of air from the lower into the upper section of the combustion chamber. Preferably, a plurality of third air passage openings are provided in the fuel support and these are distributed in particular regularly outside the closed partial surface of the fuel support.Together, the first, second and third air passage openings ensure that air and thus oxygen is provided in the combustion chamber for the combustion of fuel provided on the fuel support and the air flows through the fuel from below.According to the invention, the fuel support has a closed partial surface. In particular, the closed partial surface is formed in the fuel support and / or is part of the fuel support. The closed partial surface is arranged above the second air passage opening and completely covers the latter. This arrangement offers the advantage that ash originating from the combustion can pass from the upper section into the lower section of the combustion chamber through the at least one third air passage opening in the fuel storage device, but this does not in particular pass in regions in which the second air passage opening is arranged, so that the ash does not leave the lower section of the combustion chamber, but rather in particular remains on the inner base of the combustion chamber.For this purpose, the first air passage opening has a first planar extent, the second air passage opening has a second planar extent and the closed partial surface of the fuel support has a third planar extent. Advantageously, the first planar extent is greater than the second planar extent, in particular greater by at least 10% and preferably greater by at least 50%, and / or the third planar extent is greater than the second planar extent, in particular greater by at least 10% and preferably greater by at least 50%.The aforementioned ratio between second and third planar expansion can ensure in particular that ash can pass through the fuel support only in those regions of the latter in which there is a sufficient distance from the second passage opening, or that sufficient depositing surface for receiving or depositing such ash is provided on the inner base.The aforementioned ratio between the first and second planar expansion, on the other hand, can ensure a particularly preferred air flow of the air that has entered the furnace body into the combustion chamber, in particular in this case reinforce a chimney effect, in particular by utilizing the Venturi effect. In particular, this can also contribute to preventing ash from escaping from the combustion chamber through the second air passage opening.Particularly preferably, the first air passage opening is / are arranged centrally in the outer base and / or the second air passage opening is / are arranged centrally in the inner base and / or the closed partial surface is arranged centrally in the fuel support. In particular, the first air passage opening, the second air passage opening and the closed partial surface are preferably arranged concentrically.In particular, the lower section comprises a relative proportion of 5 to 25%, preferably 10 to 20%, of a volume of the combustion chamber. This can ensure, in particular, that, on the one hand, sufficient ash can be absorbed in the lower section, wherein, in particular, the lower section is advantageously designed to be as large as possible for this purpose, and, on the other hand, the fuel can be deposited sufficiently deeply in the combustion chamber or a sufficiently large quantity of fuel can be absorbed in the combustion chamber, in particular without a flame resulting from the combustion of the fuel leaving the upwardly open combustion chamber of the furnace body or leaving it only slightly, insofar as safety risks due to emerging flames are minimized as possible, wherein, in particular, the upper section is advantageously designed to be as large as possible for this purpose and therefore the lower section is designed as small as possible.In a preferred embodiment, the outer wall and the inner wall of the furnace body are arranged spaced apart from one another and together with an upper cover delimit a second cavity. The first and second cavities are in fluid communication with each other and / or together form a continuous cavity.Preferably, in such a configuration, at least one fourth air passage opening is formed in a lower region of the inner wall and adjacent to and above the fuel support. Alternatively or additionally, particularly preferably additionally, at least one fifth air passage opening can be formed in an upper region of the inner wall. The at least one fourth air passage opening and / or the at least one fifth air passage opening are configured to allow air to flow from the second cavity into the combustion chamber, in particular into the upper section of the combustion chamber.By means of these additional air inlet openings, further air can be supplied to the combustion, in particular at different points, which can lead to an even better mixing of fuel and air, whereby in particular an even more complete combustion can be promoted or ensured.Finally, this may result in a further reduction in the output of noxious wastes such as carbon monoxide, which may often occur in incomplete combustion.The flow of air through the second cavity toward the at least one fourth air passage opening and / or the at least one fifth air passage opening can additionally lead to cooling of the furnace body and in this case in particular of the outer wall. In this way, in particular, the risk of scalding / combustion resulting from contact with the furnace body, in particular the outer wall, can be reduced.Preferably, in particular a plurality of fourth and / or fifth air passage openings, particularly preferably a plurality of fourth and fifth air passage openings, are provided. The fourth air passage openings and / or the fifth air passage openings each advantageously have, in particular, a regular distribution along a circumference of the inner wall, and / or the fourth air passage openings and / or the fifth air passage openings are arranged along a height extension of the inner wall in each case at approximately the same height, wherein the height of the fourth air passage openings differs, in particular, from the height of the fifth air passage openings. This can advantageously lead to particularly uniform air supplies and / or can ensure that air and in particular sufficient air is supplied to the fuel or the combustion at that location where this air is required for the combustion and in particular a preferably complete combustion.In particular, the provision of a sufficiently large first air passage opening can ensure or is selected with a first planar extent of such a magnitude that sufficient air can pass into the furnace body or the first cavity and is available there for both sufficient air from the first cavity into the lower region of the combustion chamber and sufficient air to pass through the second cavity and through the fourth air passage openings and / or through the fifth air passage openings into the upper region of the combustion chamber in order in particular to ensure complete combustion and / or for chimney effects and / or Venturi effects to bring about a particularly advantageous air flow through the furnace body to the combustion chamber, and in the process in particular cooling of the outer wall can take place and / or in particular ash is prevented from emerging from the combustion chamber through the second air passage opening.In a further advantageous embodiment, a table furnace according to the invention consists at least of a first component and a second component. The first component comprises at least the outer wall and the outer bottom. The second component comprises at least the inner wall and the inner bottom. The top cover may be part of the first or second component. If necessary, the first and second components can each have an upper cover or covering surface, wherein then in particular the upper cover or covering surface of the second component can rest on the upper cover or covering surface of the first component. In particular, such a configuration is preferred. The first component and / or second component is / are advantageously each formed in one piece and / or any elements of the components are connected to one another in a materially bonded, positive-locking and / or non-positive-locking manner.Advantageously, the second component is arranged in a detachable manner in the first component and / or the fuel support is arranged in a detachable manner in the combustion chamber. In particular, the furnace body is of modular design.This makes it possible, in particular after a combustion process has been carried out, to be able to disassemble the table furnace or furnace body into, in particular modular, individual parts. This can simplify the removal of the ash and / or a cleaning of the table furnace or furnace body.In a further advantageous embodiment, the table furnace further comprises a stand. The furnace body can advantageously stand on the stand in such a way that at least one air inlet opening is formed between the stand and the outer base of the furnace body, which air inlet opening is in fluid communication with the first passage opening. This ensures in particular a sufficient inflow of air into the furnace body. In particular, the air supply through the air inlet opening to the first passage opening takes place in the lateral or horizontal direction, so that in particular a larger amount of air can be provided, in particular for optimum utilization of the chimney effect.In particular, the furnace body can be arranged detachably on the stand. This can be particularly advantageous for the transport and cleaning of the table furnace.Unless explicitly stated otherwise, advantageous embodiments described above can be combined with one another.The present figures illustrate a particularly advantageous embodiment of a table furnace according to the invention and merely serve to illustrate the furnace concept according to the invention by way of example without restricting the invention to this extent. The following are shown: FIG. 1 is a sectional view through a table furnace according to the invention; and FIG. 2 is an exploded view illustrating a modular construction of the table furnace according to the invention from FIG. 1.FIG. 1 shows a table furnace 1. the table furnace 1 consists of a furnace body 2, a fuel support 3 and a stand 4. the furnace body 2 consists of an outer wall 5, an outer bottom 6, an inner wall 7, an inner bottom 8 and an upper cover 9. the inner wall 7 and the inner bottom 8 delimit the combustion chamber 10 in which the fuel support 3 is arranged. A first cavity 11 lies between the outer base 6 and the inner base 8, and a second cavity 12 lies between the outer wall 5 and the inner wall 7.The outer base 6 has a first air passage opening 13, the inner base 8 has a second air passage opening 14, and a closed partial surface 15 and a plurality of third air passage openings 16 are provided in the fuel support, wherein third air passage openings 16 are arranged outside the closed partial surface in the fuel support, in the present case in particular uniformly distributed. The first air passage opening 13, the second air passage opening 14 and the closed partial surface 15 are arranged concentrically with respect to one another. The closed partial surface 15 completely covers the second air passage opening 14. As a result, although ash produced in a combustion can pass through the third air passage openings 16, it does not fall through the second air passage opening 14 and remains on the inner floor 8.In addition, a plurality of fourth air passage openings 17 and fifth air passage openings 18 are formed in the inner wall 7. The fourth air passage openings 17 are arranged in a lower region 19 of the inner wall 7, and the fifth air passage openings 18 are arranged in an upper region 20 of the inner wall 7.The furnace body 2 stands on spacers 21 of the stand 4, so that an air inlet opening 22 is formed between stand 4 and furnace body 2.The arrows in Fig. 1 illustrate an air flow into and through the furnace body 2 of the table furnace 1:It can be seen that air initially enters the first cavity 11 of the furnace body 2 through the air inlet opening 22 and the first air passage opening 13.A first part of the entering air subsequently passes from the first cavity 11 through the second air passage opening 14 into a lower section 23 of the combustion chamber 10, which is bounded by the inner wall 7, the inner base 8 and the fuel support 3. From there, this first part of the air can pass through the third air passage openings 16 into an upper section 24 of the combustion chamber 10 in order to participate in the combustion of fuel placed on the fuel support 3 (primary combustion).A second part of the entering air passes from the first cavity 11 into the second cavity 12 and can pass from the same through the fourth air passage openings 17 and fifth air passage openings 18 into the combustion chamber 10. Air entering the combustion chamber 10 through the fourth air ports 17 may participate in primary combustion, while air entering the combustion chamber 10 through the fifth air ports 18 supports and / or allows secondary combustion above the fuel. The secondary combustion can in particular promote the complete combustion of the fuel, in particular further minimize or even prevent the formation of carbon monoxide.Air flows shown are thereby primarily caused or promoted by the chimney effect and / or Venturi effect. For this purpose, the second air passage opening 14 is advantageously smaller than the first air passage opening 13, and the air flows through the second cavity 12 can additionally bring about cooling of the outer wall 5 and thus reduce the risk of burns and / or scalds.FIG. 2 shows a modular construction of a table furnace 1 according to the invention. The first component 25 comprises the outer wall 5, the outer base 6 and a first bearing surface 27. the second component 26 comprises the inner wall 7, the inner base 8 and a second bearing surface 28.When the furnace body 2 is assembled, the second module 26 is inserted into the first module 25, the second support surface 28 being placed on the first support surface 27. Together, the first support surface 27 and the second support surface 28 then form the upper cover 9 and the first cavity 11 and the second cavity 12 are produced.The furnace body 2 or the first module 25 can then be placed on the stand 4 or the spacers 21 forming one or more air inlet opening(s) 22, optionally for example screwed to the latter. Other, preferably releasable, types of connection of the parts are also conceivable, for example plug-in or clamping connections.Moreover, before the table furnace 1 is put into operation, the fuel support 3 is placed in the combustion chamber 10 or the second module 26.A modular construction as described above by way of example is advantageous in particular for the cleaning of the table furnace 1 after combustion has been carried out and can facilitate the latter.List of reference numbers:1 Table furnace 2 Furnace body 3 Fuel support 4 Stand 5 Outer wall 6 Outer base 7 Inner wall 8 Inner base 9 Upper cover 10 Combustion chamber 11 First cavity 12 Second cavity 13 First air passage opening 14 Second air passage opening 15 Closed partial surface 16 Third air passage opening(s) 17 Fourth air passage opening(s) 18 Fifth air passage opening(s) 19 Lower region of the inner wall 20 Upper region of the inner wall 21 Spacer 22 Air inlet opening(s) 23 Lower section of the combustion chamber 24 Upper section of the combustion chamber 25 First module 26 Second module 27 First support surface 28 Second support surfaceReferences included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedWO 2022 / 169543 A1

[0004]

Claims

Table furnace (1) having a furnace body (2) which has an upwardly open combustion chamber (10) for burning off a fuel, wherein the furnace body (2) has an outer wall (5), an inner wall (7), an outer base (6) and an inner base (8), and wherein the inner wall (7) and the inner base (8) delimit the combustion chamber (10), wherein the outer base (6) and the inner base (8) are arranged spaced apart from one another via a first cavity (11), wherein a fuel support (3) for supporting the fuel provided for combustion is arranged on the fuel support (3) in the combustion chamber (10), and the fuel support (3) divides the combustion chamber (10) into a lower section (23) and an upper section (24), wherein the furnace body (2) has a first air passage opening (13) for the inflow of air into the first cavity, wherein a second air passage opening (14) for the flow of air from the first cavity (11) into the lower section (23) of the combustion chamber (10) is formed in the inner base (8), wherein at least one third air passage opening (16) for the flow of air from the lower section (23) into the upper section (24) of the combustion chamber (10) is formed in the fuel support (3), characterized in that the fuel support (3) has a closed partial surface (15) and the closed partial surface (15) is arranged above the second air passage opening (14) and in that the closed partial surface (15) completely covers the second air passage opening (14).Table furnace (1) according to Claim 1, characterized in that the first air passage opening (13) has a first planar extent and the second air passage opening (14) has a second planar extent and the closed partial surface (15) of the fuel support (3) has a third planar extent, and in that the first planar extent is greater than the second planar extent, in particular by at least 10%, preferably by at least 50%, and / or the third planar extent is greater than the second planar extent, in particular by at least 10%, preferably by at least 50%.Table furnace (1) according to one of the preceding claims, characterized in that the first air passage opening (13) is arranged centrally in the outer base (6) and / or the second air passage opening (14) is arranged centrally in the inner base (8) and / or the closed partial surface (15) is arranged centrally in the fuel support (3).Table furnace (1) according to one of the preceding claims, characterized in that the lower section (23) comprises a relative proportion of 5 to 25%, preferably of 10 to 20%, of a volume of the combustion chamber (10).Table furnace (1) according to one of the preceding claims, characterized in that the outer wall (5) and the inner wall (7) of the furnace body (2) are arranged spaced apart from one another and together with an upper cover (9) delimit a second cavity (12), and in that the first cavity (11) and the second cavity (12) are in fluid communication with one another and / or together form a continuous cavity (11, 12).Table furnace (1) according to claim 5, characterised byat least one fourth air passage opening (17) formed in a lower region (19) of the inner wall (7) and adjacent to and above the fuel support (3) and / or by at least one fifth air passage opening (18) formed in an upper region (20) of the inner wall, wherein the at least one fourth air passage opening (17) and / or the at least one fifth air passage opening (18) are configured for the flow of air from the second cavity (12) into the combustion chamber (10).Table furnace (1) according to one of the preceding claims, characterized in that a first component (25) comprises the outer wall (5) and the outer base (6) and / or a second component (26) comprises the inner wall (7) and the inner base (8).Table furnace (1) according to claim 7, insofar as it refers directly or indirectly to claim 5, characterised in that the upper cover (9) is part of the first component (25) or second component (26), or in that the first component (25) has a first support surface (27) and the second component has a second support surface (28) and the first and second support surfaces (27, 28) together form the upper cover (9).Table furnace (1) according to one of claims 7 or 8, characterised in that the second component (26) is arranged detachably within the first component (25) and / or in and / or on the first component (25).Table furnace (1) according to one of the preceding claims, characterized in that the fuel support (3) is arranged in a detachable manner in the combustion chamber (10).Table furnace (1) according to one of the preceding claims, characterized in that the furnace body (2) is of modular design.Table furnace (1) according to one of the preceding claims, further comprising a stand (4), wherein the furnace body (2) stands on the stand (4) in such a way that at least one air inlet opening (22) is formed between the stand (4) and the outer base of the furnace body (2), wherein the at least one air inlet opening (22) is in fluid communication with the first air passage opening (13).Table furnace (1) according to claim 12, characterised in that the furnace body (2) is arranged detachably on the stand (4).

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