FLOW GUIDE ELEMENT, FLOW GUIDE SYSTEM AND HEATING DEVICE

Description

[0001] The invention relates to a flow guiding element, a flow guiding system and a heating device, in particular a mobile heating device for vehicles.

[0002] Heating devices with an evaporator burner are used in liquid fuel-operated auxiliary and / or auxiliary heaters, which are used in particular for vehicles. Fig. 1a heating device with an evaporator burner according to the prior art according to DE 10 2012 100 173 B4 is shown. This heating device 2 is designed as a mobile, fuel-operated heater for a parking heater of a motor-driven land vehicle. The evaporator burner 4 itself has, among other things, a combustion chamber 8, an evaporator receptacle 10, and an evaporator element 12 for evaporating liquid fuel. Combustion chamber 8, evaporator receptacle 10, and evaporator element 12 are designed to be essentially rotationally symmetrical. The combustion chamber 8 is delimited in the circumferential direction by a surrounding combustion chamber wall 14. At the front end, in the area of ​​the fuel supply, which is provided by a fuel supply pipe 36 and a combustion air inlet 24, the combustion chamber 8 is delimited by the evaporator receptacle 10. The evaporator element 12 is accommodated in the evaporator holder 10 on the side facing the combustion chamber 8.The evaporator burner 4 further comprises a combustion air guide element 16 on the side of the evaporator receptacle 10 facing away from the combustion chamber 8. The combustion air guide element 16 is bowl-shaped and is placed over the evaporator receptacle 10 like a cap.

[0003] A combustion air pre-chamber 20 is formed in a ring around the combustion chamber 8. A gap 18 between the bottom wall 26 and the evaporator receptacle 10 opens into the combustion air pre-chamber 20. From the combustion air pre-chamber 20, a fluid connection to the combustion chamber 8 is established via combustion air through-openings 22 formed in the combustion chamber wall 14. The gap 18 between the bottom wall 26 of the evaporator receptacle 10 and the combustion air guide element 16 extends continuously over the entire surface of the bottom wall 26 (apart from the area of ​​the combustion air inlet 24), so that the bottom wall 26 is cooled essentially over its entire surface (apart from a central area).

[0004] The fuel supply pipe 36 is arranged within the nozzle-shaped combustion air inlet 24 so that, during use, combustion air flows around it and is thereby cooled to prevent the fuel from evaporating and igniting prematurely upon entering the evaporator element 12, which can lead to pulsating combustion. A first flow path 42 for the exhaust gases is formed in a heat exchanger 6. The exhaust gases flow within the heat exchanger 6 along the first flow path 42 to an exhaust gas discharge line 44, via which the exhaust gases are guided to the outside. Furthermore, a second flow path 46 is provided within the heat exchanger 6, through which the cooling fluid of the motor vehicle is guided. The first 42 and the second 46 flow paths are arranged such that, during use, heat is effectively transferred from the exhaust gases to the cooling fluid.

[0005] For assembly reasons, the bell-shaped combustion air guide element 16 must be interrupted at least at one point. This interruption can be used to arrange a fuel supply pipe 16 or a glow plug of the burner. DE 10 2013 214 387 A1 already discloses a flow guide element in the form of an inflow element comprising a first base region and an outer peripheral wall adjoining the first base region and extending substantially in the direction of a longitudinal center axis of the inflow element, a first inner peripheral wall arranged at a radial distance from the outer peripheral wall and delimiting a spatial region therewith, and an inflow opening arrangement for the inflow of air into the inflow element. Provision is made for the inflow opening arrangement to be provided in the first base region and designed to generate a vortex flow. DE 195 07 556 A1 discloses another flow guide element.

[0006] A disadvantage of the previously described solution is that the bowl-shaped geometry limits the size of an evaporator receptacle if a fan pre-chamber is specified. Furthermore, such a flow element can only be arranged, centered and fixed on the burner with great effort. Due to the proximity to the hot burner parts, only a limited selection of materials is possible. Furthermore, especially with an eccentric fan, there is the problem that the air is guided laterally into the heating device at one point and uniform cooling can therefore not be achieved or can only be achieved with great effort. The object of the invention is to provide an improved flow guide element, flow guide system and an improved heating device, in particular a mobile heating device for vehicles.

[0007] The object of the invention is achieved with respect to the flow guiding element by the features of claim 1, with respect to the flow guiding system by the features of claim 6, and with respect to the heating device by the features of claim 8. Appropriate embodiments emerge from the respective subclaims.

[0008] The flow guide element according to the invention for a heating device, in particular a heating device with an evaporator burner, comprises a body which has a laterally arranged inflow region on an underside of the flow guide element, a centrally arranged outflow region which comprises an opening from an underside of the flow guide element to an upper side of the flow guide element opposite the underside, and at least one guide element which is arranged in such a way that it enables flow guidance from the inflow region to the outflow region.

[0009] The underside and top side of the flow guide element are two opposite sides of the flow guide element. The underside is expediently configured with a support surface, while the top side is designed to be aligned with an evaporator-combustor receptacle when installed in the heating device. An external shape, particularly as viewed in projection onto the top side of the flow guide element, is adapted to the shape of the receiving heating device, in particular a combustion air pre-chamber. The flow guide element according to the invention is particularly suitable for a heating device with a fan arranged outside a central axis, i.e., eccentrically. The flow guide element thus guides an air flow from the fan to the central outflow area in a simple and cost-effective manner.

[0010] The air guiding elements can expediently be formed by projections or walls arranged on the underside of the flow guiding element, so that channels open toward the underside are formed on the flow guiding element. Alternatively, the flow guiding elements can also be formed by closed channels.

[0011] The flow guide element is expediently a molded plastic part, in particular an injection-molded plastic part. Such a molded plastic part is cost-effective to manufacture and simplifies assembly. Suitable plastics include, for example, polyphenylene sulfite (PPS) or glass fiber-reinforced PPS, in particular PPS GF 40. In a further embodiment, the flow guide element is formed at least partially or exclusively from a metallic material or from a metallic material and one of the aforementioned plastics.

[0012] In one embodiment, the flow guide element has a recess for inserting a glow plug, which is arranged in particular on a side opposite the inflow area.

[0013] In a further embodiment, the inflow area is designed to accommodate a fan. According to the invention, the inflow area is formed as a bulge.

[0014] The bulge is curved toward the top of the flow guide element. The underside of the bulge is open.

[0015] The guide element(s) are expediently designed to fan out the air flow from the inflow area to the outflow area and / or to divide the air flow from the inflow area and direct a first portion to the outflow area and to guide a further portion around the outflow area in the circumferential direction and then to guide it radially inward to the outflow area at one or more openings. A targeted flow profile can be generated by the one or more guide elements. In order to guide part of the air flow in the circumferential direction, a circumferential wall having one or more openings can be provided at the outflow area.

[0016] In a further embodiment, the flow guide element has, on a side facing away from the guide element(s), i.e. the top side of the flow guide element, recesses for inserting a fastening element for fixing in a fan antechamber of an evaporator burner.

[0017] The flow guidance system according to the invention for a heating device, in particular a heating device with an evaporator burner, comprises a flow guidance element according to the invention and a fastening element. The fastening element can be easily fastened in the heating device, in particular in a fan antechamber or combustion antechamber. In a first embodiment, the fastening element is suitable for being clamped against the wall of the fan antechamber or combustion antechamber in order to fasten the flow guidance element and fix it in place. For this purpose, the fastening element can have projections that engage in the recesses of the wall or are supported against a smooth wall. Alternatively or additionally, the fastening element is suitable for clamping the flow guidance element such that the flow guidance element itself is clamped against the fan antechamber or combustion antechamber.

[0018] In one embodiment, the fastening element is a spring element, in particular a spring element made of spring steel, preferably in one piece. In a further embodiment, the spring element is formed at least partially from plastic, from spring steel and plastic, or exclusively from plastic. Such a spring element can in particular have two, three, four or more projections in the direction of a circumferential wall and an equal number of tongues directed inwards towards the outflow region of the flow guide element. In one embodiment, the spring element does not have a closed shape in the circumferential direction, but rather an opening which can be used to bring the fastening element into position by means of deformation. This opening is in particular aligned with a recess in the flow guide element.The flow guide element has recesses, particularly on the upper side, into which the fastening element is inserted. These recesses are designed, in particular, for the tongues and / or projections so that the flow guide element and fastening element fit together in exactly one orientation. Furthermore, the fastening element, in particular the spring element, in particular the tongues of the spring element, can be designed to come into contact with an evaporator-combustor receptacle or evaporator holder, in particular a bottom-side projection of the evaporator-combustor receptacle or evaporator holder, when installed. The spring element can be advantageously tensioned by the pressure of the bottom-side projection on the tongues.

[0019] The heating device according to the invention with an evaporator burner with a fan pre-chamber and an eccentric fan comprises a flow guidance system according to the invention.

[0020] In the design, the flow guide element is self-centering and accommodated in the blower chamber.

[0021] The invention will be explained in more detail below with regard to further features and advantages based on the description of exemplary embodiments and with reference to the accompanying drawings. Each of these drawings shows a schematic diagram: Fig. 1 Heating device according to the prior art; Fig. 2 First view of a flow guide element; Fig. 3 Fastening element; Fig. 4 View of an open heating device; Fig. 5 Second view of a first embodiment of a flow guide element; Fig. 6 Second view of a second embodiment of a flow guide element; and Fig. 7 Second view of a third embodiment of a flow guide element.

[0022] Fig. 2shows a first view of a flow guide element. This flow guide element 100 has an outer border that is adapted to a receiving area in a combustion air prechamber. The flow guide element 100 has an inflow area 102 in an outer area that is adapted to the position of a fan. This fan is eccentrically arranged.

[0023] Furthermore, the flow guide element 100 has a central outflow region 104, which allows the air to pass from an underside of the flow guide element 100 to an upper side of the flow guide element. Guide elements 106 are arranged on the underside of the flow guide element 100. The flow guide element 100 can, for example, be a molded plastic part.

[0024] The flow guide element 100 has a recess 108 for receiving a glow plug. Furthermore, in the Fig. 2shown top side, a first recess 112 and a second recess 114 are shown. The first recess has a peripheral shape of the Fig. 3shown fastening element 120. The fastening element 120 can be inserted into the first recess 112 and second recesses 114. With the fastening element 120, the flow guide element can be easily fastened in the heating device, in particular a fan antechamber or combustion antechamber. This fastening element 120 has three projections that extend radially outward. The second recesses 114 are designed for the three inwardly directed tongues 122 of the fastening element 120. The fastening element 120 does not have a closed shape in the circumferential direction, but rather an opening which can be used to position the fastening element 120 by means of deformation. This opening is designed to be aligned with the recess 108 of the flow guide element 100.The fastening element is suitable both for bracing the flow guide element 100 and for supporting it with two of the projections against a wall of the blower chamber 20. The fastening element 120 is preferably a spring element, which can be made, for example, from spring steel.

[0025] Fig. 4shows a view of an open heating device with a flow guide element 100 inserted in a combustion air prechamber 20 and a fastening element 120. An underside of the flow guide element 100 rests on an upper side of a floor of the combustion air prechamber 20. The fastening element 120 is arranged on the upper side of the flow guide element 100. The fastening element 120 is thus arranged towards an evaporator-combustor receptacle or evaporator holder (not shown). The tongues 122 of the fastening element 120 are designed in particular to come into contact with a dome or bottom-side projection of the evaporator-combustor receptacle or evaporator holder when installed. Due to the pressure of the bottom-side projection of the evaporator-combustor receptacle or evaporator holder on the tongues 122, the fastening element 120 designed as the spring element can be advantageously tensioned.With the help of the fastening element 120, the flow guide element 100 is thus held in the desired position.

[0026] Fig. 5 to 7 show different designs of the underside of a flow guide element. Fig. 5 The embodiment shown has, on the one hand, the upper recess for the tongue 122 of the fastening element 120 as a guide element 106. Furthermore, it has a guide element 106 which is designed as a circumferential wall around the outflow area 104. The guide elements 106 of this embodiment are designed to guide the air from the inflow area 102 to the outflow area 104 over relatively short paths, thereby expanding the air flow. This embodiment guides air over very short paths to an evaporator receptacle arranged above the outflow area 104, thus achieving strong cooling.

[0027] Fig. 6shows a further embodiment of the flow guide element 100 from a bottom side. This flow guide element 100 differs in particular in a different design of the guide element 106 arranged around the outflow area 104, which is also closed in the area of ​​the recess 108.

[0028] Fig. 7 shows a further embodiment of the flow guide element 100. This embodiment differs in that a guide element 106 arranged around the outflow area 104 forms a circumferential flow channel provided with openings 110. This flow channel with the openings 110 is suitable for directing the air from different sides to the outflow area 104. This achieves a very uniform flow through the outflow area 104, and an evaporator receptacle arranged above the outflow area 104 can be cooled particularly uniformly. List of reference symbols

[0029] 2 Heating device 4 Evaporator burner 8 Combustion chamber 10 Evaporator mount 12 Evaporator element 16 Combustion air guide element 14 Combustion chamber wall 18 Gap 20 Combustion air antechamber 22 Combustion air through-openings 26 Bottom wall 24 Combustion air inlet 36 Supply pipe 42 First flow path 44 Exhaust gas discharge 46 Second flow path 100 Flow guide element 102 Inflow area 104 Outflow area 106 Guide element 108 Recess 110 Opening 112 First recess 114 Second recess 120Fastener 122Tongue tThickness

Claims

1. Flow-directing element (100) for a heating apparatus (2), in particular a heating apparatus (2) with an evaporator burner (4) having a body which comprises a laterally arranged inflow region (102) on an underside of the flow-directing element, having a centrally arranged outflow region (104), which comprises a through-passage from an underside of the flow-directing element to an upper side of the flow-directing element, the upper side being located opposite the underside, and having at least one guide element (106) which is arranged such that it allows flow to be guided from the inflow region to the outflow region, wherein the inflow region (102) is designed as a bulge.

2. Flow-directing element according to claim 1, wherein the flow-directing element (100) is a molded plastic part, in particular a plastic injection moulded part.

3. Flow-directing element (100) according to claim 1 or 2, wherein the flow-directing element (100) has a recess (108) for inserting a glow plug, which is arranged in particular on a side opposite the inflow region (102).

4. Flow-directing element (100) according to one of the preceding claims, wherein the guide element or elements (106) are designed to expand the air flow from the inflow region (102) to the outflow region (104) in a fan-like manner, and / or to divide the air flow from the inflow region (102) and to guide a first part to the outflow region (104) and to guide a further part around the outflow region (104) in the peripheral direction and then to guide it radially inwards to the outflow region (104) at one or more openings (110).

5. Flow-directing element (100) according to one of the preceding claims, the flow-directing element (100) having, on a side facing away from the guide element or elements (106), recesses (112, 114) for the insertion of a fastening element (120) for fixing in a blower vestibule or combustion air vestibule (20) of an evaporator burner (4).

6. Flow-directing system for a heating apparatus (2), in particular a heating apparatus with an evaporator burner (4), comprising a flow-directing element (100) according to one of the claims 1 to 5 and a fastening element (120).

7. Flow-directing system according to claim 6, wherein the fastening element (120) is a spring element, in particular a spring element made of spring steel.

8. Heating apparatus (2) with an evaporator burner (4) with a blower vestibule or combustion air vestibule (20) and an eccentric blower, comprising a flow-directing system according to claim 6 or 7.

9. Heating apparatus (2) according to claim 8, wherein the flow-directing element is received in the blower space or combustion air vestibule (20) in a self-centering manner.