Burner assembly for a mobile heater and insert component with retaining ring for an evaporator

Abstract

Burner assembly (1) for a mobile fuel-operated heater, in particular for a vehicle, comprising: - an evaporator (20) arranged to evaporate a fuel supplied to it; - an evaporator holder (24) designed to receive the evaporator (20); - a peripheral wall (16) defining a combustion chamber (14) in which a gas mixture containing the vaporized fuel can be burned, the peripheral wall (16) defining a central axis (M); - a glow plug (10) with a shaft section (12) having a glow element, which is designed to convert a current flowing through it when a voltage is applied into heat for igniting the gas mixture; - a first opening (15) formed in the peripheral wall (16) of the combustion chamber (14) and through which the shaft portion (12) of the glow plug (10) extends substantially radially into the combustion chamber (14); characterized by - a mounting arrangement (44, 45, 46, 17, 8) for the glow plug (10), which is designed to allow pivotability of the shaft section (12) of the glow plug (10) within the combustion chamber (14) in a direction (R) along the center axis (M) away from the evaporator (20).

Description

Technical area:

[0001] The present invention relates to a burner assembly for a mobile, combustion-based heating device, in particular in a vehicle, as well as an insert component with a retaining ring for an evaporator that can be used in such a burner assembly. Technical background:

[0002] It is known that burner assemblies are used in evaporator burners, which are frequently used in vehicles, for example as parking heaters or auxiliary heaters, etc. These are operated with liquid fuel. In such evaporator burners, liquid fuel is fed into an evaporator via a fuel supply line. Structures used as evaporators can include, for example, metal fleece, metal grids and knitted metal fabrics or basalt wool, etc. In particular, the structure used in the evaporator has a large number of cavities so that the liquid fuel is sucked up by the evaporator through capillary action and the evaporator is permeated with fuel. In order to start a combustion process in an evaporator burner, heat must initially be supplied to the evaporator via an external heat source. This is usually done by an electrically operated glow element ora glow plug is provided which initiates the starting process.

[0003] For the purpose of rapid and highly efficient heat supply, the glow plug is arranged in a combustion chamber as close as possible to the evaporator in a fixed position. A conventional example of such an arrangement is shown in the Fig. 1 using a burner assembly 100. A combustion chamber 14 is defined by a peripheral wall 16. At the front, an evaporator 20 is received in an evaporator receptacle 24 and held by a retaining element 30 integrated therein. The evaporator 20 is supplied with fuel via a fuel supply line 22. An axial assembly method in the axial direction (joining direction), which greatly simplifies production, is accommodated by an axial arrangement of a glow plug 10. A disadvantage is that the evaporator 20 is locally interrupted in order to allow the passage of the glow plug 10 into the combustion chamber 14. The secure and spatially defined positioning of the glow plug 10 is ensured by a plug socket 90.

[0004] An arrangement of a burner assembly 200 according to a conventional example reducing the complexity of the evaporator 20 is shown in Fig. 2. The same reference numerals are used for the same or similar components or elements. In contrast to, for example, Fig. 1, the glow plug 10 is mounted radially and extends from a peripheral wall formed in the evaporator receptacle 24 radially into its interior, which is now part of the combustion chamber 14. The term “radial” can also include deviations from an exact perpendicular to a center axis of the combustion chamber 14 and rather refers to the lateral access to the combustion chamber 14, as is also the case in Fig. 2. This access is also made possible by a socket 90, which ensures secure and spatially defined positioning of the glow plug 10 relative to the evaporator 20.

[0005] It should be noted that the arrangement of the plug socket 90 laterally on the evaporator mount 24 extends the axial length of the latter relative to the burner flange 64. The corresponding projection 66 is not available for the installation of elements of the heat exchanger (not shown), so that the overall length of the evaporator burner could be longer than necessary unless other measures are taken. On the other hand, arranging the plug socket 90 on the peripheral wall 16 of the combustion chamber 14 would complicate the axial joining direction of the components and entail additional folding processes, which would increase manufacturing costs and time. An alternative design would therefore be desirable.

[0006] It should also be noted that, instead of the rigid plug socket 90, screw sockets are also known in the prior art, which interact with screw threads provided on the glow plug. In the case of the plug socket 90, split pins are often provided to prevent them from falling out or to lock them into a fixed position. After removing such split pins, the glow plugs can be moved and pulled out of the plug socket.

[0007] The described fixation of a glow plug 10 using a plug or screw socket 90 forms a rigid structure by which the glow plug 10 is reliably and precisely held in a desired position or orientation with respect to the evaporator 20 and the combustion chamber 14. However, this position, once determined, can only take changing conditions with different operating times and different operating settings into account to a limited extent. Description of the invention:

[0008] The present invention is therefore based on the object of providing a burner assembly or individual components thereof in which the disadvantages described above are avoided or at least reduced.

[0009] According to various aspects of the invention, a burner assembly for a mobile heater, in particular for a vehicle, is proposed. The burner assembly comprises an evaporator, an evaporator receptacle, a peripheral wall with a first opening, a glow plug, and a mounting arrangement for the glow plug.

[0010] The evaporator is designed to evaporate a fuel supplied to it. The invention is not limited to specific types or shapes of evaporators. The evaporator can be disc-shaped. It can be made of a porous fleece, mesh, knitted fabric, warp-knitted fabric, and / or woven fabric, in particular metal (fiber) fleece, metal mesh, metal knit, metal warp-knitted fabric, metal woven fabric, and / or metal sponge, or at least partially of a textile fiber molded body. Basalt wool is also suitable. Alternatively or in addition to metal, other (heat-resistant) materials, such as plastic and / or ceramic, can also be used. In particular, the evaporator can be made at least partially of a porous, heat-resistant metal, preferably at least partially of steel, in particular a stainless steel alloy (e.g., 1.4841 or 1.4767). The diameter of the evaporator can be, for example, between 20 mm and 80 mm, and the thickness can be, for example,between 0.7 mm and 5 mm; all information is provided without limitation of generality. The evaporator can be designed in several stages, for example, with cascading changes in porosity or material properties (evaporator dome). The fuel can be any fuel that is still liquid when supplied, for example, diesel, gasoline, ethanol, kerosene, or the like.

[0011] The evaporator mount is designed to accommodate the evaporator. The evaporator can be pressed into the evaporator mount, for which purpose the evaporator mount provides a corresponding cavity whose shape matches that of the evaporator. The evaporator and the evaporator mount, in particular, represent separate components.

[0012] The peripheral wall defines a combustion chamber within it, in which a gas mixture containing the fuel vaporized (by the vaporizer) can burn. The peripheral wall is preferably cylindrical, but the aspects of the invention are not limited to this specific shape and configuration. According to embodiments, air inlet holes can be provided in the peripheral wall, some of which are radially directed, and others which interact to generate a swirl for better mixing of the gas mixture. According to optional embodiments, narrowing regions, a flame tube, and channels of a heat exchanger, etc., can be connected downstream of the peripheral wall in a known manner.

[0013] The peripheral wall defines a central axis M. Depending on the design, this axis can be a cylindrical axis or another axis of symmetry. However, symmetry is not necessarily required. The central axis extends along the overall flow direction of the gases flowing through it.

[0014] The glow plug is provided with a shaft section containing a glow element, which is designed to convert a current flowing through it when an electrical voltage is applied into heat to ignite the gas mixture. The glow plug can have a head with electrical connection electronics and the shaft section. Optionally, the shaft section can partially have a metal or ceramic sleeve that protects against mechanical damage, etc., in the first opening.

[0015] A first opening can be formed in the peripheral wall, through which the shaft section of the glow plug extends substantially radially into the combustion chamber. The opening does not constitute a bushing. The cross-section of the first opening can roughly correspond to the cross-sectional profile of the shaft section or the aforementioned additional section, but this does not result in spatial fixation. As described, "radial" refers to the type of design with lateral insertion of the glow plug, as opposed to an axial design. This means that "radial" does not strictly require an orientation perpendicular to the center axis M of the combustion chamber.

[0016] Aspects of the invention now provide a mounting arrangement for the glow plug that can replace the conventional socket, in particular a plug socket or screw socket, so that the burner assembly preferably does not include a plug socket or screw socket. This mounting arrangement is configured to allow the shaft portion of the glow plug to pivot within the combustion chamber in a direction R along the center axis M away from and / or toward the evaporator.

[0017] As described, in conventional cases a glow plug is fixed or rigidly oriented by the bushing and cannot adapt or change to changing conditions over its operating life or service life. In the case of gasoline burners, for example, undesirable deformation of the evaporator can occur over its operating life or service life due to deposits and residues. It has been found that, depending on the type, optimal alignments and positioning for the glow plug can be considered where the distance to the evaporator is so small that the deformations lead to contact between the evaporator and the glow plug or its shaft section. This finding is also accompanied by increasingly longer service lives of burner assemblies and evaporator burners, which are achieved through quality improvements in the products.

[0018] Over time, the increasing contact between the evaporator and the glow plug causes the evaporator to exert a force Fd1 on the shaft section, threatening to push it toward the center axis. In the conventional case of rigid bushing fixation, this can lead to material fatigue and fracture of the shaft section, rendering the evaporator burner inoperable. Alternatively, the shaft section may not fracture but become encased in deposits, which also leads to inoperability.

[0019] The mounting arrangement provided according to the aspects, however, now allows the shaft section to deflect in a direction away from the evaporator. This ensures that the glow plug's function is maintained even after extended operation or service life, at least as long as the overall deformation does not impair the available combustion chamber.

[0020] Due to the first opening in the peripheral wall, through which the shaft section extends, this can form a type of pivot point for the permitted pivoting movement. The mounting arrangement arranged outside the combustion chamber forms the rear bearing of the glow plug with respect to the glow plug, which enables the pivoting movement. The pivotability results in a rotary movement being carried out; the direction R away from the evaporator therefore corresponds to a circular movement. Since the compensating movement with respect to the deformation of the evaporator involves small angles - starting from a radial arrangement - for the adjustment, without loss of generality, a pivoting range of a total of 20° or less, or even 15° or less, for example 10°, for the purposes of the present application, one can also speak of a pivoting movement of the shaft section that is essentially parallel to the central axis M.

[0021] The mounting arrangement can have any desired design in the general case considered here. Embodiments to be described below provide, in addition to the first opening, a second opening therein, which forms a second bearing for the glow plug, but now allows linear mobility for a rear portion of the glow plug. These embodiments provide active guidance of the rear portion of the glow plug by spring tension directed in the direction of the degree of freedom of linear movement and, as a result, presses the shaft portion toward the evaporator—in the case of contact, against the deformation force Fd1. Since the tension force Fs of the spring element is less than the deformation force Fd1, the shaft portion retreats, but the spring force Fs holds the shaft portion in position near the evaporator.

[0022] It should also be noted that instead of the described mounting of the glow plug in the first opening as a pivot point and the second opening of the support arrangement as a bearing with a degree of freedom of linear movement, the support point of the support arrangement can also be designed as a pivot point, while the glow plug can move linearly in the first opening - with the same consequence as described above.

[0023] For example, a sliding element could be provided in the first opening, which is now designed as an elongated hole, which receives the shaft section and is moved with it - e.g. under spring tension or against friction, around the pivot point of the mounting arrangement - and which at the same time covers exposed areas of the first opening for closing the combustion chamber on the one hand.

[0024] The above description of the pivot point and bearing with linear mobility serves merely to simply describe the possibilities of how the mounting arrangement according to the invention can be implemented in practice. Other options for movable bearings are also possible, for example, a ball bearing, etc., in which the glow plug can be mounted accordingly.

[0025] It should also be noted that diesel and gasoline burners are conventionally configured with different distances between the glow plugs and the evaporator. Thanks to the mounting element provided separately from the combustion chamber wall, separate combustion chamber assemblies no longer need to be installed for each burner type; instead, individual design can be achieved simply by adjusting the mounting arrangement.

[0026] Furthermore, by eliminating the bushings, they no longer need to be laboriously welded to the evaporator mount or combustion chamber wall as individual components, or be designed as an integral part of the same, which saves costs, time, and effort. As described, the aspects and embodiments also increase the service life of the evaporator burners.

[0027] According to a special development of the burner assembly, the mounting arrangement—as indicated above—can comprise a spring element that is operatively connected to the glow plug and configured to apply a spring force Fs to the glow plug, which presses the shaft section, preferably toward the evaporator. As already described above purely by way of example, this holds the glow plug in position. However, due to the comparatively greater counterforce Fd1, it can retract in the opposite direction due to deformation of the evaporator, thus preventing damage and / or inoperability.

[0028] According to a further development of the burner assembly, the mounting arrangement comprises a holding element that is fixedly positioned with respect to the evaporator receptacle and / or the peripheral wall. The holding element comprises a second opening that lies opposite the first opening outside the combustion chamber, at least partially overlapping it, with the shaft portion of the glow plug extending through the second opening. This achieves a largely radial positioning of the glow plug. The second opening corresponds to the second bearing point described above purely by way of example and in general terms.

[0029] According to a further development of the burner assembly, a length of the second opening parallel to the central axis M is greater than a length of the first opening parallel to the central axis M. With the same shaft cross-section at the points of passage through the two openings, the glow plug can thus be movable within the second opening at least in one direction that is essentially perpendicular to a direction in which it extends. In the first opening, however, this is hardly or not at all the case, although a pivot point function of the first opening is retained.

[0030] According to a corresponding development of the burner assembly, the shaft section has a cross-sectional profile, wherein the second opening has an opening area that is larger than the cross-sectional profile.

[0031] According to a further development of the burner assembly, the first opening has a first contact surface and the second opening has a second contact surface, wherein the first contact surface and the second contact surface delimit the respective openings on the side facing away from the evaporator, wherein the spring element is configured to exert the spring force Fs on the shaft portion of the glow plug and thereby press it against both contact surfaces. In particular, the spring element can exert its spring force Fs perpendicular to the direction of extension of the glow plug and thus exert a leverage force on the shaft portion located in the combustion chamber in the direction of the evaporator. This represents a particularly simple design.

[0032] According to a further development of the burner assembly, a position of the second contact surface projected onto the center axis M and a position of the first contact surface projected onto the center axis M essentially coincide. This achieves a nearly ideal radial home position, which is only canceled when the evaporator comes into contact with the shaft section of the glow plug and drives the shaft section toward the center axis. In this case, the shaft section (or the additional section, if present) detaches from the second contact surface against the tension force of the spring element, while contact with the first contact surface (as the pivot point) is maintained.

[0033] According to a further development of the burner assembly, the holding element is formed integrally with a retaining ring, which is designed to hold and press the evaporator in the evaporator receptacle. This and the following special aspects are particularly advantageous because the implementation of the holding arrangement can be carried out particularly easily with few components and in a volume-saving manner. The holding element and the retaining ring can be combined and, in an integral design, form an insert component for the burner assembly. For example, the combined element comprising the retaining ring for the evaporator and the holding element for the glow plug can be manufactured from a simple, connected deep-drawn insert sheet. By combining several functions in one component, the number of individual parts and the amount of welding processes required in series can be reduced, thus simplifying assembly.Furthermore, the possibility of complete assembly from only one direction is ensured by the integrated component consisting of the retaining ring and holding element.

[0034] A refinement provides that the retaining ring further comprises a circumferential flange section, which is received between a burner flange formed integrally with the peripheral wall and an evaporator mounting flange and is preferably welded to them. The integrated retaining ring with flange allows a frontal boundary of the combustion chamber to be shifted so that the evaporator mounting no longer limits the combustion chamber (see Fig. 2). The retaining ring with flange now fits completely between the two. Supported by external regulation, the heat balance in the evaporator can be better controlled, allowing the burner to be used with different fuels. In the case of the integral insert component, or specifically the insert sheet, this can be placed between the flanges of the evaporator mount and the combustion chamber, and all three components are permanently connected with a single welding process. The wall thickness of the sheet metal part is preferably kept as small as possible to ensure a weld that meets the requirements.

[0035] The retaining element can extend outwardly from the flange section. In order to reach the section of the peripheral wall comprising the first opening downstream (toward the combustion chamber outlet or flame tube), the retaining element can be bent accordingly by, for example, 90°. The second opening is formed in the retaining element, and the bending is carried out such that the two openings are located opposite one another at a suitable distance, i.e., the retaining element is also arranged approximately parallel to an outer surface of the peripheral wall. Due to the integral formation with the retaining ring and the flange section, the position and orientation of the retaining element is robust and consistent.

[0036] A further development of this aspect of the burner assembly provides that the retaining ring further comprises a cylindrical portion and an adjoining holding portion with an inner opening. The cylindrical portion and the holding portion together form a pot shape, which accommodates the evaporator opposite the evaporator receptacle and presses it in place. This completes the dual function of the retaining ring with the holding element.

[0037] A further improvement can be achieved if the inner opening is closed by a grid through which the vaporized fuel can pass. The grid can, in particular, hold fibrous vaporizer materials or basalt wool, etc., in their shape.

[0038] A further aspect of the invention provides an insert component for a burner assembly for a mobile heater. The insert component preferably comprises an integral design: - a retaining ring for an evaporator with a holding section for pressing the evaporator into an evaporator receptacle of the burner assembly, with an inner opening for releasing a fuel evaporated by the evaporator into a combustion chamber of the burner assembly and with a flange section for fastening the retaining ring to a burner flange formed integrally with a peripheral wall of the combustion chamber and to an evaporator receptacle flange; and - a holding element for holding a glow plug outside the combustion chamber and for determining an orientation of a shaft portion of the glow plug within the combustion chamber.

[0039] The advantages are the same as those described above with regard to the integrated retaining ring in the burner assembly. However, this aspect of the invention is not necessarily limited by the pivotability of the glow plug. In particular, the first and second openings can also be of equal size. Nevertheless, some of the aforementioned advantages are achieved. The other features described above with regard to the retaining ring and the mounting arrangement with the retaining element can also further develop this aspect. Short description of the drawings:

[0040] The invention is explained below by way of example with reference to the following figures.

[0041] They show: Fig. 1 a sectional view through a burner assembly according to a first example from the prior art with axial arrangement of the glow plug; Fig. 2 a sectional view through a burner assembly according to a second example from the prior art with radial arrangement of the glow plug; Fig. 3 a sectional view through a burner assembly according to an embodiment with a radial arrangement of the glow plug; Fig. 4A a perspective view of the spring element from Fig. 3; Fig. 4B is an enlarged view of the elements of the mounting arrangement of Fig. 3, without glow plug; Fig. 5 another enlarged view of the elements of the mounting arrangement of Fig. 3, with glow plug; Fig. 6 a schematic representation of the opposing openings of the holder arrangement with possible resulting pivoting positions of the glow plug; Fig. 7 like Fig. 3, but in perspective sectional view; and Fig. 8 an insert component with a retaining ring and with an integrally formed retaining element according to an embodiment. Detailed description of preferred embodiments:

[0042] In the following description of the drawings, the same reference symbols refer to the same or comparable components.

[0043] The features of the invention disclosed in the above description, in the drawings and in the claims may be essential for the realization of the invention both individually and in any combination.

[0044] In the Fig. 3 shows a sectional view through a burner assembly 1 according to an embodiment with a radial arrangement of the glow plug 10. The burner assembly 1 comprises a combustion chamber 14 defined by a cylindrical peripheral wall 16, an evaporator receptacle 24, an evaporator 20 received by the latter, and a retaining ring 40 with a retaining element 44 formed integrally thereon. The combustion chamber 14 and the peripheral wall 16 define a central axis M. Smaller, radially aligned air inlet holes 18 and swirl-generating air inlet holes 18, so-called flaps, are formed in the peripheral wall 16. The combustion chamber 14 tapers in the downstream direction (in Fig. 3 downwards). The evaporator receptacle 24 has a frame 25 with a pot-shaped receptacle for the evaporator 20. The evaporator 20 is pressed into this receptacle. Without limiting the generality, the evaporator 20 can be basalt wool. Above the evaporator 20, an evaporator dome is formed in the evaporator receptacle 24, into which a further evaporator (without reference symbol) of varying porosity can be inserted. During operation, a fuel such as gasoline, diesel, ethanol, etc. can be supplied to the evaporator 20 via a fuel supply line 22 via the evaporator dome.

[0045] The evaporator holder 24 forms a frontal closure for the burner assembly 1. However, the combustion chamber 14 is enclosed at the front by the retaining ring 40 and a grid 50 arranged therein above or within an inner opening 48 (see Fig. 8) so that the evaporator receptacle 24 is (advantageously) no longer in direct contact with the combustion chamber 14. The retaining ring 40, together with the grid 50, has the task of maintaining the compression of the evaporator 20 in the evaporator receptacle 24. During operation, the supplied fuel is evaporated in the evaporator 20 and passes via the grid 50 into the combustion chamber 14, where it is mixed with the air through the air inlet holes and burns after initial ignition by the glow plug 10.

[0046] The glow plug 10 has a shape known as such in this technical field. The glow plug 10 comprises a head 11, which, among other things, has a connection electronics. The glow plug 10 is supplied with electrical power via electrical connection lines 9. Furthermore, the glow plug 10 has a shaft section 12, which extends in a substantially radial direction through a first opening 15 (compare the Fig. 4B and Fig. 5) in the peripheral wall 16 extends into the combustion chamber 14. The first opening 15 is designed as a mere recess in the combustion chamber wall without any internal or external structures. In particular, it is not designed as a plug-in or screw-in socket. A cross-sectional profile of the first opening 15 essentially corresponds to a cross-sectional profile of the shaft section 12 of the glow plug 10. The first opening 15 can be rounded by the amount of a manufacturing tolerance as well as due to manufacturing-related roundings in the corners (cf. Fig. 8) be designed slightly larger than the cross-sectional profile of the shaft section 12.

[0047] With reference to the Fig. 4A and Fig. 4B and 5, the holding arrangement 4 is described in greater detail. The holding arrangement 4 comprises a tab or holding element 44 for the glow plug 10, which is integrally connected to a flange section 41 of the holding ring 40. The flange section 41 extends in a plane perpendicular to the center axis M of the combustion chamber 14 and parallel to an extension plane of the evaporator 20 and a holding section 49 forming the opening 48 of the holding ring 40 with the grille 50 arranged thereon. With the aid of a flat cylindrical section 47 of the holding ring 40, the holding ring 40, like the evaporator receptacle 24, forms a flat pot shape, which in turn accommodates the corresponding pot shape of the frame 25 of the evaporator receptacle 24 for the evaporator 20. The holding ring 40 therefore has a relatively flat structure.

[0048] As in Fig. 4B is indicated by the dotted line, the flange section 41 together with a combustion chamber flange 17 and an evaporator receiving flange 26 forms a flange package 6 (cf. Fig. 3 and Fig. 7), by which it is enclosed (in a sandwich construction). The dotted line schematically indicates a weld seam. The flange section 41 extends circumferentially within the retaining ring, thus achieving a completely closed connection with the combustion chamber flange 17 and the evaporator mounting flange 26.

[0049] Since the flange portion 41 is exposed to the outside environment with its outer edge, the tab-like retaining element 44 can extend in an integral manner from the flange portion 41 into the outside environment of the combustion chamber 14. As can be seen in the figures, the tab-like retaining element 44 is bent 90° in the downstream direction at a slight distance from the peripheral wall 16, and then extends parallel to the center axis M to the center axis M and the peripheral wall 16.

[0050] Overall, the retaining ring 40 with the mounting arrangement 4 or the holding element 44 in the exemplary embodiment is formed by a deep-drawn and bent, flat insert component. As shown in the Fig. 4B, the wall thickness of the insert component (e.g., 0.8 mm) corresponds approximately to that of the peripheral wall 16 (e.g., 1 mm) of the combustion chamber 14. This also facilitates the welding of the above-mentioned flange sections. A second opening 45 is formed in the tab-like retaining element 44. As shown in Fig. 3 and the Fig. 5, the shaft section 12 extends through both the first opening 15 and the second opening 45. In the optional case that the glow plug 10 has a metal or ceramic sleeve, this can be in direct contact with the openings 15, 45 as part of the shaft section 12 of the glow plug 10.

[0051] As in the Fig. 5, a spring element 8 is arranged between the shaft section 12 and the combustion chamber 14, which also in the Fig. 4A. The spring element 8 is designed here as a resilient split pin, which is compressed between the shaft section 12 and the combustion chamber 14. In other words, the spring element 8, supported on the combustion chamber flange 17, exerts a Fig. 5 downward clamping force on the shaft section 12, ie in the downstream direction or parallel to the center axis M and to the opening surfaces of the first opening 15 and the second opening 45, and - depending on the current pivoting position of the glow plug - substantially or approximately perpendicular to the direction of extension of the glow plug 10. By means of this clamping force, the shaft section 12 is pressed against corresponding contact surfaces 151, 451 of the first and second openings 15, 45.

[0052] As in the Fig. 6, the first opening 15 has a smaller length in a direction parallel to the central axis M than the second opening 45. The length of the first opening 15 in the direction parallel to the central axis M corresponds approximately to the diameter of the shaft section 12, while the length of the second opening 45 in the direction parallel to the central axis M is greater than the diameter of the shaft section 12. As a result, the shaft section 12 can move in the second opening 45 in the direction parallel to the central axis M, which is not the case with regard to the first opening 45. This results in a possible rotational movement of the glow plug 10, so that the shaft section 12 can basically move towards or away from the evaporator 20, as indicated by the double arrow in the Fig. 3, which indicates the corresponding direction of rotation R, which is essentially parallel to the center axis M for small swivel ranges.

[0053] According to a specific non-limiting embodiment, due to the mutual arrangement and size of the openings 15, 45, the shaft section 12 can be inclined in an initial state 12a, in which the shaft section touches the two contact surfaces 151 and 451, by 2° towards the evaporator with respect to an exact radial direction perpendicular to the central axis, and in a state 12b, in which the shaft section 12 is released from the contact surface 451 and contacts an opposite contact surface 452 (maximum pivoting range), by 8° away from the evaporator with respect to the exact radial direction perpendicular to the central axis. The permitted pivoting range is therefore 10°. The pivoting range is so small that it can be reflected in length differences of the Fig. 3, Fig. 4B, Fig. 5 and Fig. 7 shown openings, which is why the difference in the Fig. 6 is exaggerated to illustrate the effect.

[0054] The spring element 8 is designed as a split pin as described. Fig. 4A shows that this split pin has a bulbous base section 81, a pressure section 82, a contact section 83 and an end section 84. The contact section 83 lies flat against the combustion chamber flange 17 in the installed state. The bulbous base section 81 or the end section 84 lie in this state against a holding flange 46, which is bent by the tab-like holding element 44 by another 90° towards the peripheral wall 16 in order to hold the spring element 8 in position. The end section 84, like the base section 81, bulges in the downstream direction in the installed state, i.e. Fig. 4B downward, while the intermediate pressure section 82 rests on the shaft section 12. To secure the radial position of the shaft section 12, it has a groove (not shown) into which the pressure section 82 can engage. A cooling vane 88 can be interposed between the pressure section 82 and the surface of the groove.

[0055] Returning to Fig. 6, in particular, the pressure section 82 of the spring element 8 presses the shaft section 12 against the contact surfaces 151 and 451, so that the glow plug 10, despite its basic mobility, assumes a predetermined position relative to the combustion chamber 14 and the evaporator 20. Due to deposits during operation over its service life, the evaporator 20 can deform and, in the process, come into contact, for example, with a distal region of the shaft section 12. As a result, a force Fd1 is exerted on the shaft section 12. The first opening 15 forms a pivot point for the glow plug 10. Accordingly, the force Fd1 exerted on the shaft section 12 is transformed into a lever force Fd2, with which the pressure section 82 of the spring element 8 is pushed back against its own tension force Fs, which is designed to be significantly lower.Nevertheless, this clamping force Fs holds the glow plug 10 in position, with the distal area of ​​the shaft section 12 in contact with the continuously deforming evaporator. This process continues throughout the service life. At the same time, the shaft section 12 is protected from damage.

[0056] The Fig. 7 shows again an overview of the burner assembly 1 as in Fig. 3, but in perspective sectional view.

[0057] The Fig. 8 shows an embodiment of an insert component 400 with integrally formed retaining ring 40 and retaining element 44 for the glow plug 10 as well as with grid 50. that in Fig. The embodiment shown in Figure 8 can be identical to the one shown in Fig. 3 to 7 shown retaining ring 40, so that the detailed description can be omitted.

[0058] It should be noted, however, that according to another aspect, the embodiment of an insert component 400 as shown in Fig. 8 can be modified such that the second opening 45 can also be formed with a cross-sectional area corresponding to the shaft section 12. In this case, the glow plug cannot be guided or moved laterally within the second opening 45. In other words, in this case, the spatial position of the glow plug 10 is essentially fixed and rigid. Fig. 3, 4A, and 5 - 7 can therefore only serve to fix / secure the glow plug 10 in the holder arrangement 4 in the radial direction in this embodiment.

[0059] The modified embodiment can be used in conjunction with the Fig.3, 4A, and 5-7, the features of the burner assembly 1 shown without mobility of the glow plug do not take into account the deformation of the evaporator 20 over its service life. However, a simple and cost-effective insert component can still be advantageously realized, which, on the one hand, allows a flat design of the evaporator receptacle 24 and thus a shortening of the overall length of the evaporator burner, and, on the other hand, enables axial assembly of the components for the evaporator. The complex production of plug-in or screw-type sockets can be eliminated. List of reference symbols 1 burner assembly 4 Mounting arrangement (includes numbers 44, 45, 46, 17, 8) 6 welded flange package 8 spring element 9 Electrical connection cables 10 glow plug 11 head 12 Shaft section 14 Combustion chamber 15 first opening 151 contact area 16 peripheral wall (combustion chamber) 17 Combustion chamber flange 18 air inlet holes 20 evaporators 22 Fuel supply line 24 Evaporator holder 25 Mounting frame (for evaporator in evaporator holder) 26 Evaporator mounting flange 30 Holding element (conventional) 40 Retaining ring (invention) 41 Flange section 44 Holding element 45 second opening 451 contact area 46 Retaining flange (on bracket assembly to support the spring element) 47 cylindrical section 48 Opening 49 stopping section 400 insert component 50 grids 81 Base Section 82 Print section 83 Annex section 84 final section 88 cooling vane 90 socket, plug socket 100 evaporator burner (state of the art): axial bushing for glow plug 200 evaporator burner (state of the art): radial bushing for glow plug M center axis R (swivel) direction of the glow plug

Claims

[1] Burner assembly (1) for a mobile fuel-operated heating appliance, in particular for a vehicle, comprising: - an evaporator (20) which is configured to evaporate a fuel supplied to it; - an evaporator receptacle (24) designed to accommodate the evaporator (20); - a circumferential wall (16) defining a combustion chamber (14) in which a gas mixture containing the vaporized fuel can be burned, wherein the circumferential wall (16) defines a central axis (M); - a glow plug (10) with a shaft section (12) having a glowing element, which is arranged to convert a current flowing through it when a voltage is applied into heat for igniting the gas mixture; - a first opening (15) which is formed in the circumferential wall (16) of the combustion chamber (14) and through which the shaft section (12) of the glow plug (10) extends substantially radially into the combustion chamber (14); characterized by - a mounting arrangement (44, 45, 46, 17, 8) for the glow plug (10) which is designed to allow the shaft section (12) of the glow plug (10) to pivot within the combustion chamber (14) in a direction (R) along the central axis (M) away from the evaporator (20). [2] Burner assembly (1) according to claim 1, wherein the mounting arrangement (44, 45, 46, 17, 8) has a spring element (8) which is in operative connection with the glow pin (10) and is arranged to act on the glow pin (10) with a spring force (Fs) which presses the shaft section (12), preferably in direction (R) towards the evaporator (20). [3] Burner assembly (1) according to claim 2, wherein the mounting arrangement (44, 45, 46, 17, 8) comprises a retaining element (44) fixedly positioned with respect to the evaporator receptacle (24) and / or the circumferential wall (16), wherein the retaining element (44) comprises a second opening (45) which is at least partially overlapping with the first opening (15) outside the combustion chamber (14), wherein the shaft section (12) of the glow plug (10) extends through the second opening (45). [4] Burner assembly (1) according to claim 3, wherein the length of the second opening (45) parallel to the central axis (M) is greater than the length of the first opening (15) parallel to the central axis (M). [5] Burner assembly (1) according to one of claims 3 or 4, wherein the shaft section (12) of the glow plug (10) has a cross-sectional profile, wherein the second opening (45) has an opening area that is larger than the cross-sectional profile. [6] Burner assembly (1) according to any one of claims 3 to 5, wherein the first opening (15) has a first mounting surface (151) and the second opening (45) has a second mounting surface (451), wherein the first mounting surface (151) and the second mounting surface (451) define the respective openings (15, 45) on the side facing away from the evaporator (20), wherein the spring element (8) is arranged to exert the spring force (Fs) on the shaft section (12) of the glow plug (10) and thereby press it against both contact surfaces (151, 451). [7] Burner assembly (1) according to claim 6, wherein a position of the second contact surface (451) projected radially onto the central axis (M) corresponds to a position of the first contact surface (151) projected radially onto the central axis (M). [8] Burner assembly (1) according to one of claims 3 to 7, wherein the retaining element (44) is integrally formed with a retaining ring (40) which is configured to hold and press the evaporator (20) in the evaporator receptacle (24). [9] Burner assembly (1) according to claim 8, wherein the retaining ring (40) further comprises a circumferential flange section (41) which is received and / or welded between a burner flange (17) integrally formed with the circumferential wall (16) and an evaporator receiving flange (26). [10] Burner assembly (1) according to claim 8 or 9, wherein the retaining ring (40) further comprises a cylindrical section (47) and a retaining section (49) adjoining it with an inner opening (48), the cylindrical section (47) and the retaining section (49) together form a pot shape, the evaporator receptacle (24) opposite the evaporator receiving the evaporator (20) and presses it in. [11] Burner assembly (1) according to claim 10, wherein the inner opening (48) is closed by a grid (50) through which the vaporized fuel can pass. [12] Fuel-operated mobile heating appliance, in particular for a vehicle, comprising a burner assembly (1) according to any one of the preceding claims. [13] Insert component (400) for a burner assembly (1) for a mobile fuel-operated heating appliance, comprising: - a retaining ring (40) for an evaporator (20) with a retaining section (49) for pressing the evaporator (20) into an evaporator receptacle (24) of the burner assembly (1), with an inner opening (48) for releasing fuel vaporized by the evaporator (20) into a combustion chamber (14) of the burner assembly (1), and with a flange section (41) for attaching the retaining ring (40) to a burner flange (17) integrally formed with a circumferential wall (16) of the combustion chamber (14) and an evaporator receptacle flange (26); and - a retaining element (44) for holding a glow plug (10) outside and for determining an orientation of a shaft section (12) of the glow plug (10) inside the combustion chamber (14), - wherein the retaining element (44) is integrally formed with the retaining ring (40). [14] Insert component (400) according to claim 13, wherein the retaining ring (40) further comprises a cylindrical section (47) which extends in an axial direction between the retaining section (49) and the flange section (41).

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