Vaporiser component, in particular for a vehicle heating device

p0001The present invention relates to an evaporator assembly, in particular for a vehicle heater, comprising a support, porous evaporator medium on the carrier, and a fuel supply line for feeding liquid fuel through an opening in the carrier in the porous evaporator medium.

p0002The <patcit id="pcit0001" dnum="DE102004020507A1"><text>DE 10 2004 020 507 A1</text></patcit> discloses an evaporator arrangement for producing a hydrocarbon vapor / mixed material mixture, wherein in the bottom area of ​​the evaporator housing porous evaporator material is arranged. A guided through a bottom wall fuel supply liquid hydrocarbon is introduced into the porous evaporator medium. In order to obtain a direct fuel transfer between the fuel supply and the porous evaporator medium here, this on its side facing the bottom wall back can be provided with a recess, which is engaged by the free end of the fuel supply such that a cut-like edge region at the free end of the fuel supply in the porous evaporator medium engages. Thus, the output from the fuel supply liquid hydrocarbon enters directly into the internal volume portion of the porous evaporator medium.

p0003The <patcit id="pcit0002" dnum="DE10120027A1"><text>DE 101 20 027 A1</text></patcit> discloses an evaporator assembly for a heater for heating the interior of a vehicle, in which in a dish-like carrier a porous evaporator medium is arranged. By a bottom wall of the carrier therethrough is introduced via a fuel supply liquid fuel. The back of the porous evaporator medium is covered by a provided with passage openings plate so that between the bottom wall of the dish-like carrier, and the entire back surface of the porous evaporator medium, a buffer volume is formed, in which the liquid fuel entering after exiting from the fuel supply. Through the passage apertures of the vorverteilte in this manner already over the entire back side of the porous evaporator medium liquid fuel passes into the interior volume portion of the porous evaporator medium.

p0004It is the object of the present invention to provide an evaporator assembly, and in particular to provide for a vehicle heater, is wherein for an improved distribution behavior of the output from a fuel supply liquid fuel provided in a porous evaporator medium.

p0005According to the invention this object is solved by an evaporator assembly, in particular for a vehicle heater, comprising a support on the carrier porous evaporator medium and a fuel supply line for feeding liquid fuel through an opening in the carrier in the porous evaporator medium, wherein an intermediate storage volume at least in part in the formed porous evaporator medium for receiving liquid fuel from the fuel supply line and for passing on the received therein liquid fuel into the evaporative medium-porous.

p0006Characterized in that, in the structure according to the invention an intermediate storage volume is at least partly formed in the porous evaporator medium itself, on the one hand the possibility is created that the emerging from the fuel supply fuel penetrates already deeper into the porous evaporator medium in the range of this intermediate storage volume. At the same time, an enlarged surface area is provided which is limited, the intermediate storage volume is formed in the porous evaporator medium and through which the liquid fuel is then taken up in the porous evaporator medium and distributed there by Kapillarförderwirkung on.

p0007Due to the configuration of the intermediate storage volume at least in part in the porous evaporator medium, this porous evaporator medium where an intermediate storage volume is present, generally have a lower material thickness. To prevent from the fuel supply dispensed and which enters the buffer volume of liquid fuel passes directly through the porous evaporator medium and is discharged in droplet-like shape toward a combustion chamber or vaporization chamber, it is proposed that at least lying in a discharge port of the fuel supply to surface area the porous evaporator medium being formed with a lower porosity, than in an intended for discharge of fuel vapor surface area of ​​the porous evaporator medium. To use this effect as efficiently as possible, for example, can be provided that the porous evaporator medium is formed in its entire volume the latch facing surface area with lower porosity.

p0008A large-surface contact as possible between the porous evaporator medium and the carrier can be achieved in that the intermediate storage volume is formed only in the porous evaporator medium. This configuration will continue to ensure that does not take place for emerging on the back of the porous evaporator medium crevice-like gaps between the support and the porous evaporator medium an undefined, especially strong gravitational influence fuel distribution.

p0009In an alternative embodiment it can be provided that the intermediate storage volume is formed in the carrier part. This can be particularly advantageous if the receptacle for used liquid fuel interior of the intermediate storage volume is to be made as large as possible with only limited thickness of the porous evaporator medium.

p0010In a particularly simple to realize embodiment can be provided that the intermediate storage volume is formed in the porous evaporator medium by embossing. In this way the production of the intermediate storage volume while helping ensure that the porous structure of the porous evaporator medium in the region surrounding the intermediate storage volume changed by the pressing load in such a way that there is a lower porosity is present, as in the then remote lying volume areas. As already explained above, this is particularly advantageous in that the through spraying of fuel can be avoided by the relatively thin porous evaporator medium.

p0011In order to achieve a uniform distribution of the liquid fuel in the porous evaporator medium through the intermediate storage volume, it is proposed that the intermediate storage volume in one - is provided central region of the porous evaporator medium - relative to a longitudinal center axis of the carrier. The fuel supply may - eccentrically open out into this - relative to a longitudinal center axis of the carrier. This simplifies the combination with other modules. This eccentric introduction may in particular be used for example in a vehicle this in combination with the mounting position of such evaporator assembly to compensate for poor gravitational distribution characteristics.

p0012To support the evaporation of in the buffer volume introduced into the porous evaporator medium liquid fuel, an electrically energizable heating means may be provided on a side facing away from the porous evaporator medium side of the support.

p0013In another particularly advantageous embodiment variant, it may be provided that the porous evaporator medium substantially completely rests in his no buffer volume-providing area on the carrier. By substantially complete abutment with the support on the one hand the previously already mentioned may be undesirable gaps in accordance with an undefined distribution performance can be avoided. On the other hand, especially when an electrically excitable heater to assist the evaporation of fuel, an improved heat transfer between the heater and the porous evaporator medium are ensured in this way.

p0014The present invention is described below in detail with reference to the accompanying drawings. It shows:<dl id="dl0001"><dt>Fig. 1</dt><dd>a partial-sectional view of an evaporator assembly;</dd><dt>Fig.2</dt><dd>a view of the in <figref idrefs="f0001">Fig. 1</figref> Assembly shown in the direction II in <figref idrefs="f0001">Fig. 1</figref>,</dd></dl>

p0015In the <figref idrefs="f0001">Fig. 1</figref> Evaporator assembly partially illustrated is generally designated by 10. The evaporator assembly 10 includes a molded, for example from sheet metal support 12 having a bottom wall 14 and one in the<figref idrefs="f0001">FIG. 2</figref> recognizable in an outer region of the bottom wall 14 adjacent peripheral wall 16. This thus essentially cup-like-structured carrier 12 a porous evaporator medium 18 is provided. This porous evaporator medium 18 may be composed for example of metal mesh, metal fiber or other porous material, such. As ceramic foam, sintered material or the like. The porous evaporator medium 18 is substantially full contact with the bottom wall 14 and on the peripheral wall 16 of the switch-like carrier and the like can in this by soldering, gluing, Sintering. be held. In a central region of the dish-like support 12 which is substantially also defined by the longitudinal central axis L of this path 18 has a forward direction of the porous evaporator medium forming 20 with an opening 22nd In this opening 22 a free end 24 of an established example of metal pipe fuel supply line 26 is inserted and is fixed, for example by soldering. A seal member 28 can produce a further fluid-tight seal between the molding 20 and the free end 24 of the fuel supply line 26th

p0016A discharge opening 30 at the free end 24 of the fuel supply line 26 26 supplied liquid fuel can be delivered into the interior of the cup-like support 12, in particular towards the porous evaporator medium 18 of such fuel supply. This porous evaporator medium 18 has in its opening 30 opposite region by a recess or a depression 32-supplied buffer volume 34. Thus, the exiting through the opening 30 from the fuel supply pipe 96 liquid fuel passes first into the recess 32 and the buffer volume 34, and enters at the said intermediate storage volume 34 bounding surface 36 of the porous evaporative medium 18 in this porous evaporator medium. As compared to the diameter of the opening 30, the intermediate storage volume 34 having a significantly greater transverse dimension takes place in the region of the transition of the fuel supply line 26 to the porous evaporator medium 18 is already a pre-distribution of the supplied liquid fuel rather than that due to the fact that the intermediate storage volume 34 in the embodiment shown is formed entirely in the porous evaporator medium 18, already takes place in an integrated in the total volume of this porous evaporator medium 18 range. The liquid fuel can thus be absorbed through the surface 36 and are quickly and evenly distributed in the interior volume portion of the porous evaporator medium 18th The depression 32, ie, the buffer volume 34, can, in a particularly advantageous embodiment, in the porous evaporator medium by embossing, for example by means of a die, take place. The consequence of this method of production of the intermediate storage volume is that in which the surface 36 is close volume area 38 is acting on the pore structure of the porous evaporator medium, that in this volume area 38 has a lower porosity is present, than in the adjoining or further bulk regions of the porous evaporator medium, , in particular the surface 40 of the same near-volume range over which then carried out the delivery of the fuel, for example in the direction of a combustion chamber. Thus, it is ensured that in particular in that region of the porous evaporator medium 18, which faces directly the opening 30, a through syringes of the liquid fuel through the porous evaporative medium 18, which has a reduced thickness in this area is avoided. Since the volume region 38 with lower porosity substantially all of the intermediate storage volume surrounds 34, is nevertheless ensured that the admission of the liquid fuel is effected substantially uniformly into the porous evaporative medium 18 over the surface area 36th The embossing process is, however, mean that in the opening 30 opposite portion of the surface 36, the porosity is less than in a depression the 32 surrounding peripheral area 42nd

p0017The <figref idrefs="f0001">Fig. 1 and 2</figref> show that the depression 32 is arranged with respect to a longitudinal center axis L of the dish-like support 12 is substantially centered. One recognizes further that, for example, the depression 32 may be formed with substantially circular geometry. The fuel supply line 26 and its opening 30 is, however, relative to the longitudinal center axis L displaced and thus supplies the liquid fuel is not in the central region of the depression 32 of the intermediate storage volume 34 a. Here, advantageously the arrangement as in<figref idrefs="f0001">FIG. 2</figref> be shown, so the opening of the fuel supply are 32 in an upper region of the depression, so that even when the gravity-induced movement of the liquid fuel in the recess 32 down the overhead areas of the surface 36 may be covered with liquid fuel and there fuel will enter into the porous evaporator medium 18th

p0018It can be seen in <figref idrefs="f0001">Fig. 1</figref> Next arranged at the end remote from the porous evaporator medium 18 side of the bottom wall 14 of the carrier 12 electrically excitable heater 44, for example in the form of a heating coil or a heat conductor extending in any other way. By electrically energizing the heater 40 and the transfer of heat through the bottom wall 14 through the evaporator medium poröse- the liquid fuel contained in the porous evaporator medium 18 is heated and thus supports its evaporation. Since, as<figref idrefs="f0001">Fig. 1</figref> shows the porous evaporator medium 18 where there is no intermediate storage volume is present, substantially completely abuts against the dish-like support 14, a very good heat transfer from the shell-like support on the porous evaporator medium 18 is ensured. At the same time the occurrence of columns like gaps is avoided, could routed through which liquid fuel in the adjoining portion of the porous evaporator medium 18 to the tray-like carrier and there also emerge toward the combustion chamber.

p0019With the configuration of an evaporator assembly according to the invention it is possible to take simple measures a positive impact on the distribution behavior of the liquid fuel in the porous evaporator Mediumd. It should be noted that while the principles of the present invention can also be achieved with constructive versions that differ what is shown. Thus, although the embodiment of the intermediate storage volume is entirely in the porous evaporator medium advantageous, but may of course be formed a portion of this intermediate storage volume by appropriate shaping of the carrier in the carrier itself. If desired, may be formed, which may form part of the intermediate storage volume of course running in the carrier at the back of the porous evaporator medium Vorverteilungskanäle. Also, it is to be understood that the support may be plate-like for the porous evaporator medium and may form a floor assembly, for example, in connection with the porous evaporator medium and the heating device, which can then be inserted into a the peripheral wall of a combustion chamber or vaporization chamber-providing assembly.