DE1579792A1 - Liquid fuel heater, especially for vehicles - Google Patents

Description

WEBASTO WERK G, Μ «Β» Η «8031 Stookdnrf, August 4th

Baa / Rö. - B 74 -

Heating device operated with liquid fuel, in particular for vehicles.

The invention relates to a heating device operated with liquid fuel, in particular for vehicles whose combustion chamber has the Combustion air is supplied via a blower that is at least $ 90 of the combustion air intake line, the combustion chamber, the Exhaust pipe and, if necessary, the silencer composing the heating air supply resistance has to be overcome, and an air volume of conveys at least 4 »5 m / h.

Heaters of this type have already been built in a wide variety of designs. A radial fan was usually used to convey the combustion air, which in vehicle heating devices had the disadvantage that they could only be installed at certain points due to the exhaust gas extensions that could not be used or only with difficulty, and even then there was a tendency to malfunction at higher speeds. For smaller air flow rates (below 4 »5 m / h) therefore it is already gone over to equip the heaters with a positive displacement, the n with discharge pressures ^v ° 200 mm WS works. For a variety of reasons, however, the use of these fans was unsatisfactory for larger delivery quantities, so that up to now one had to limit oneself to the usual radial fans and delivery pressures of at most 50 mm water column. The use of higher pressures, especially in the case of larger heating devices, was also opposed by the fact that, because of the prescribed thickness of the heating duct walls, a heavy construction, which was expensive to manufacture, was required for the heat exchanger.

The invention is now based on the object of creating a heater that is completely independent of the effects of stagnant winds with a combustion air delivery of over 4 * 5 m / h, with almost any length

009835/0260

Exhaust pipes can be equipped and yet meet the respective requirements , particularly in the case of vehicles, in terms of spatial dimensions, weight and the input power.

To solve this problem, it is proposed according to the invention to use the principle of pressure increase in heaters of the type described at the beginning and the size mentioned (combustion air above 4.5 m / h), that is, the combustion air intake duct, the combustion chamber, the exhaust pipe and, if necessary, the silencer to be dimensioned in such a way that the heating air flow resistance is at least 150 at the WS, and to use a fan as the combustion air fan which is provided with an annular duct located directly next to the blades of the fan wheel, from which the combustion air enters the fan several times and from this is fed back into the ring channel before it leaves the fan through the fan outlet. The excessive pressure not only enables the use of long exhaust pipes without making the device susceptible to interference from the effects of stagnant winds, but it also allows an extremely small heat exchanger to be built, for which the thick walls of the hot gas duct are negligible , and which because of its Space-saving construction easily accommodates läsat anywhere. On the other hand, the use of the side channel blower, which has been known for decades, not only enables high pressures with small spatial dimensions, but also ensures, as long tests have shown, a relatively low drive power for these pressures and an extremely low susceptibility to failure compared to the displacement blowers.

In a preferred embodiment of the heating device according to the invention , the fuel for operating the same is metered into the pressure line of the combustion air blower in a manner known per se. With the high pressures available, not only can a relatively robust metering device be built, but also a good mixing of fuel and combustion air is achieved without having to convey the fuel through the combustion air fan «

BAD ORHSiNAL

009835/0260

To the drive power of the heating device according to the invention To keep within limits, it is also proposed that the blades des.Yerbrnungluftgebläserad, seen perpendicular to the wheel axis, from lateral air inlet from diagonally to the rear, i.e. in the opposite direction to the direction of rotation, whereby the mean angle of inclination related to the axis parallel is between 10 and 40, preferably between 20 ° and 35 °.

In the following explanation of the drawings, an exemplary embodiment is described, along with its further features of the invention are shown:

In Fig. 1 is an embodiment of the inventive

Heating device with a partially shown in section Combustion air blower shown that

in Fig. 2 in section perpendicular to the drive axis in the direction of the annular channel and

in Fig. 3 (only the impeller) in the same section, but illustrated again in the direction of the impeller is.

Bie FIG. 4 shows a section through that shown in FIG Paddle wheel along the line IV-IV.

The heating device illustrated in FIG. 1 consists of a heat exchanger 1, in which the heating gas duct 2 with a displacement body 3 'and the ignition device 4 are shown in dashed lines. The fuel that the Erennstoffördereinrichtung 5 via the from a not shown storage container coming line 6 is supplied, passes from de .t to a metering device 7 and further over the Bre »- nerauleitung 8 to Heizgaskanal 2. The exhaust gases then flow over the Exhaust pipe 9 leads the silencer 10 to the exhaust 11.

The combustion air, on the other hand, is sucked in by the fan 13 equipped with a drive motor 12 through the opening 14 and enters the annular duct 15. from there into the impeller 16, from where it flows back several times on its way to the outlet I7 also shown in FIG ^ h. in the Ringkar.al semicircular »

As can be seen from FIG. 1, the direction of rotation is indicated by the arrow of the paddle wheel is indicated, the blades run from

0.09835 / 0260 bath

the side entry from diagonally against the direction of rotation to the rear. The inclination angle related to the axis parallel is in the example 20 °. . ^;

The combustion air reaches the metering device from outlet 17 7 and flows "from there" on to the one described for the fuel Path.

It should also be noted that in FIG. 1 the combustion air fan compared to the other / parts of the heater was not reproduced in the same size ratio, what from the connection line can be seen between the combustion air fan and the metering device is.

Of course, the invention is not limited to what is shown Embodiment is limited, but can be iji of the most varied Modify and complement in a wise way.

Claims (1)

^ν " ^ & te η ta η s ρ r ü σ fa e Heating device operated with liquid fuel: in particular for vehicles whose combustion chamber is supplied with the combustion air via a bubble that is at least 90% of the size of the combustion chamber. air intake line, .the combustion chamber ,; the exhaust pipe and, if applicable, the. Silencer. Composition of the hot air delivery resistance: - was able to overcome, and an air volume of at least 4.5 m / h -requires thereby geke η η ζ ei without t that the combustion air intake duct, the combustion chamber, the exhaust pipe and, if necessary, the Sehalldämpfer are sized so that the heating ^{'luftf'örderwideretan.d'mxnde:} siteiis 150 mm water column, and, as he "bren · - voltage air blower, a?. Blower is used, which is connected to a non-communicable next to; the view of a ring-shaped * lying on the fan. Duct provided isty% όπ your from the combustion air; -..- ■ -. several times Si enters the fan wheel - and from this into the. Ring duct - is conveyed back before it leaves the fan through the fan outlet. * · He.izvorricht.ung according to claim 1, since d lir chgeke η η ζ eic hn _et; diassi in a manner known per se the pressure line of the combustion air ge biases the fuel for the operation of the heating device; rt; rt; 3 :. Heating arrangement according to claim. 1,. through this. geke η η ζ eic ha et ,, that; ÄJLe S'chamffe.ln the combustion air fan; seen perpendicular to the wheel axis>. from the side air inlet diagonally -to the rear ^ - that is, run in the opposite direction to the direction of rotation, with the mean angle of inclination ζ wi ac hen 1Q and 40, preferably between 20 and 55 * BAD ORlQlNAL