U.S. patent application number 10/086356 was filed with the patent office on 2002-09-12 for ignition device, particularly for an atomizer burner of a motor vehicle heating appliance.
Invention is credited to Blaschke, Walter, Eberspach, Gunter.
Application Number | 20020127506 10/086356 |
Document ID | / |
Family ID | 7676728 |
Filed Date | 2002-09-12 |
United States Patent
Application |
20020127506 |
Kind Code |
A1 |
Eberspach, Gunter ; et
al. |
September 12, 2002 |
Ignition device, particularly for an atomizer burner of a motor
vehicle heating appliance
Abstract
An ignition device, in particular for an atomizer burner of a
motor vehicle heating appliance, comprises a glow ignition member
and screening material, which can take up fuel and which surrounds
the glow ignition member at least over a region.
Inventors: |
Eberspach, Gunter;
(Wolfschlugen, DE) ; Blaschke, Walter; (Deizisau,
DE) |
Correspondence
Address: |
M. Robert Kestenbaum
11011 Bermuda Dunes NE
Albuquerque
NM
87111
US
|
Family ID: |
7676728 |
Appl. No.: |
10/086356 |
Filed: |
February 28, 2002 |
Current U.S.
Class: |
431/262 ;
431/263 |
Current CPC
Class: |
F23Q 7/22 20130101; F23Q
7/001 20130101 |
Class at
Publication: |
431/262 ;
431/263 |
International
Class: |
F23Q 007/06 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 8, 2001 |
DE |
101 11 153.3-23 |
Claims
We claim:
1. An ignition device comprising a glow ignition member (12), and a
screening material (32) that takes up fuel and surrounds the glow
ignition member (12) at least over a region.
2. The ignition device according to claim 1, further comprising an
atomizer nozzle (26), wherein the glow ignition member (12) is
substantially completely screened by the screening material (32)
against direct flow onto the glow ignition member (12) of material
delivered by the atomizer nozzle (26).
3. The ignition device according to claim 1, wherein the screening
material (32) is spaced, at least over a region, from the glow
ignition member (12).
4. The ignition device according to claim 1, further comprising a
support arrangement, wherein the glow ignition member (12) is
supported by the support arrangement (16, 20), and the screening
material (32) is spaced, at least over a region, from the support
arrangement (16, 20).
5. The ignition device according to claim 1, wherein the glow
ignition member (12) is elongate and comprises a free end region
(18) and the screening material (32) extends at least along the
free end region (18) of the glow ignition member (12).
6. The ignition device according to claim 5, wherein the screening
material (32) extends out over the free end region (18) of the glow
ignition member (12).
7. The ignition device according to claim 5, wherein the screening
material (32) forms a screening material member substantially
cylindrically surrounding the glow ignition member (12).
8. The ignition device according to claim 1, wherein the screening
material (32) comprises porous material.
9. The ignition device according to claim 1, wherein the screening
material (32) comprises mesh-like material.
10. The ignition device according to claim 1, for an atomizer
burner of a motor vehicle heating appliance.
11. The ignition device according to claim 8, wherein the porous
material comprises foamed ceramic material.
12. The ignition device according to claim 9, wherein the mesh-like
material comprises wire mesh.
13. Heating appliance comprising a heating burner, and at least one
ignition device (10) according to claim 1.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
[0003] 1. Background of the Invention
[0004] The present invention relates to an ignition device,
particularly for an atomizer burner of a motor vehicle heating
appliance.
[0005] 2. Technical Field
[0006] In heating appliances, such as are used as so-called
supplementary heaters or auxiliary heaters in motor vehicles, fuel
is fed together with combustion air into a combustion chamber and
is combusted there. The combustion is ignited by so-called spark
gaps, such as also find application in heating burners in heating
installations of buildings. The spark gaps provided for ignition,
as used in particular in connection with so-called atomizer
burners, in which the fuel to be burned is injected together with
the combustion air at high speed and thus atomized, are
comparatively expensive and thus represent a not inconsiderable
cost factor, particularly for smaller kinds of heating devices.
SUMMARY OF THE INVENTION
[0007] The present invention has as its object to provide a
cost-efficient ignition device which in particular can also be used
in connection with atomizer burners.
[0008] This object is attained according to the invention by an
ignition device, particularly for an atomizer burner of a motor
vehicle heating appliance, including a glow ignition member and
screening material which can take up fuel and which at least
partially surrounds the glow ignition member.
[0009] Departing from the procedure, known from the prior art, of
using spark gaps for the ignition of atomizer burners, the present
invention takes the path of using an ignition device, working on
the principle of a glow ignition device, which is markedly more
cost-effective to obtain and to build in. This was heretofore not
possible, since the removal of heat from a glow ignition member was
very great due to the flow speed of the materials injected into the
combustion chamber in the case of atomizer burners, so that the
glow ignition member could no longer produce, even in its immediate
neighborhood, the temperature required for the ignition of the
combustion materials. Since however according to the invention the
glow ignition member is screened by screening material, the heat
transfer to the material flowing at high speed is markedly reduced.
Instead of this, the fuel injected at high speed together with
combustion air and thus atomized is taken up in the screening
material, so that fuel collects in the immediate surroundings of
the glow ignition member, which is screened from a high speed flow,
and can now be ignited by the glow ignition member.
[0010] It should be mentioned here that as used in the present
invention, the expression "material which can take up fuel"
includes material which because of its design forms cavities in
which the fuel can collect; a direct impingement of the fuel into
the material itself does not necessarily have to take place.
Nevertheless, materials are also included which have a bodily
structure such that the fuel is taken up into them and thus, for
example, absorbed, as is the case for a porous material.
[0011] In order to be able as far as possible to exclude heat
removal from the glow ignition member due to the flow, it is
proposed that the glow ignition member is substantially completely
screened against direct flow onto it of material delivered by an
atomizer nozzle.
[0012] When the screening material is arranged spaced from the glow
ignition member at least in a region, an atmosphere whose flow is
calmed down can be produced in the space region between the
screening material and the glow ignition member, and can very
easily be ignited by the glow ignition member.
[0013] In a further embodiment of the ignition device according to
the invention, it can be provided that the glow ignition member is
carried by a support arrangement and that screening material is
arranged spaced from the support arrangement at least in a region.
By this measure, heat transfer from the screening material to the
support arrangement is made difficult, so that the ignition
efficiency of the ignition device according to the invention can be
further improved.
[0014] For example, it can be provided that the glow ignition
member is elongate, and that the screening material extends at
least along a free end region of the glow ignition member. In order
to be able to thereby attain as good as possible a screening
action, it can be provided that the screening material extends out
over the free end region of the glow ignition member. The screening
material can form a screening material member substantially
cylindrically surrounding the glow ignition member.
[0015] As materials for the screening material, for example, porous
materials can be used, foamed ceramic material being a useful
material here because of its thermal and mechanical resistance. The
use of mesh-like material such as e.g., wire mesh, is also
possible. It should be mentioned that the expression "mesh" is to
express the fact that material sections are present which
interengage or overlap one another in the manner of a mesh, warp
knit fabric, weft knit fabric, or woven fabric. A limitation to a
given manner of production of this mesh-like material is not
thereby introduced.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The present invention is described hereinbelow with
reference to the accompanying drawings, in which:
[0017] FIG. 1 shows a sectional view of a first embodiment of an
ignition device according to the invention,
[0018] FIG.2 shows a view corresponding to FIG. 1, of an
alternative embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0019] A glow ignition member is generally denoted in FIG. 1 by the
numeral 10. The glow ignition member 10 comprises a glow plug or a
glow pin 12 of conventional construction, which can thus have, for
example, a heating coil and if necessary a control coil as well as
insulating powder or the like, in a heat-resistant glow tube. The
glow pin 12 is supported in a support member 16 provided with an
external thread 14, and projects over this support portion 16 with
its free end region 18, which for example then contains the heating
coil. The support member 16 is supported in a substantially
cylindrical support sleeve 20 with an internal thread 21. The
support sleeve 20 can be installed on a housing 22, shown
schematically, of a heating burner 24. This heating burner 24
furthermore has an atomizer nozzle 26, shown schematically.
Combustion air is introduced at high speed into the combustion
chamber 28 of the heating burner 24 by means of the atomizer nozzle
26. The combustion air, flowing in, entrains the fuel and atomizes
it, so that a mixture of combustion air and very fine fuel
particles, denoted by 30 in FIG. 1, is produced and flows at high
speed into the combustion chamber 28.
[0020] In the variant embodiment shown in FIG. 1, the free end
region 18 projects beyond the housing wall 22 into the combustion
chamber 28. In order to protect this free end region of the glow
pin 12 from the air/particle stream flowing in at comparatively
high speed, a substantially cylindrical screening member 32 is
provided. This extends, with the formation of an interspace 34, at
a spacing along the free end region 18 of the glow pin 12, and thus
along that region of the glow pin 12 which projects beyond the
support member 16. The screening member 32, in its section
extending along the support sleeve 20, then abuts on, and is
supported on, the inner surface of the support sleeve 20. The
screening member 32 extends, together with the free end region 18
of the glow pin 12, into the combustion chamber 28, and in fact in
the embodiment example shown, as far as the free end region 18 of
the glow pin 12 extends also. In this manner, at least a portion of
the air/particle stream 30 delivered from the atomizer nozzle 26 is
prevented from directly striking the surface of the glow pin
12.
[0021] The screening member 32 is such, or is formed of such
material, that fuel which is contained in the air/particle stream
30 striking this screening member 32 can be taken up in this
screening member 32. For example, the use is possible of a member
formed of wire mesh, or of a porous material such as, for example,
foamed ceramic. The fuel taken up in the screening member 32 or
absorbed into it is transported to the inside, i.e. the side toward
the glow pin 12, of the screening body 32, on the one hand by the
fuel newly flowing on from the outside, and possibly on the other
hand by capillary action. An atmosphere enriched with fuel is thus
formed in this region and also in the space region 34. Since the
glow pin 12 or its free end region 18 is now extensively screened
against the air/particle stream 30, the removal of heat from the
glow pin 12 due to flow is reduced to such an extent that the glow
pin 12 can produce a temperature in its surroundings which is
sufficient for the ignition of the fuel present there. After the
resulting ignition, the combustion immediately propagates over the
whole combustion chamber 28.
[0022] The present invention thus provides the possibility, even in
so-called atomizer burners, of employing glow pins, which are very
cost-effective in comparison with spark gaps, for the ignition of
the injected air/fuel mixture, since the region of the glow pin
relevant for igniting this mixture is extensively screened against
the mixture flowing on at high speed and thus against an excessive
removal of heat induced by flow.
[0023] In the embodiment variant shown in FIG. 2, the glow pin 12,
or its free end region 18, is arranged such that it does not
project into the combustion chamber 28, or does not project so far
into the combustion chamber 28 as in the embodiment according to
FIG. 1. The screening material surrounding the free end region 18
of the glow pin 12, i.e., the screening member 32 of substantially
cylindrical constitution, however extends out over the free end
region 18 of the glow pin 12 here, and if necessary even into the
combustion chamber 28. A still better screening of the free end
region 18 of the glow pin 12 is thus attained. Here an extension of
the screening member 32 like a hood in its region projecting beyond
the free end region 18 of the glow pin 12 could also be considered,
thus completely excluding the direct flow of the air/particle
stream 30 onto the glow pin 12.
[0024] It can furthermore be seen in FIG. 2 that an interspace 36
is created between the support sleeve 20 and the screening member
32 in the end region of the support sleeve 20 near to the housing
wall 22. This interspace leads to an improved thermal insulation of
the screening member 32 with respect to the support sleeve 20 and
thus reduces the removal of heat from the region relevant for
ignition.
[0025] It should be mentioned that in both embodiments described
hereinabove, the material which can take up fuel particles, i.e.,
the screening member 32, can contact the glow pin 12 or its free
end region 18 at least over a region, so that the screening member
32 can already be brought to a markedly higher temperature. It is
also of course possible to adapt both the glow pin 12 and also the
screening member 32 as regards their design, dimensions, and
positioning with respect to the atomizer nozzle.
[0026] In addition to markedly lower material costs in comparison
to an ignition device constituted with spark gaps, the ignition
device according to the invention, working on the principle of a
glow ignition, can be operated with comparatively lower electrical
power.
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