U.S. patent application number 13/044849 was filed with the patent office on 2011-09-08 for modular tank system for a liquid reducing agent with a sump element and motor vehicle having the system.
This patent application is currently assigned to EMITEC GESELLSCHAFT FUR EMISSIONSTECHNOLOGIE MGH. Invention is credited to ROLF BRUCK, JAN HODGSON, MARTIN REINER.
Application Number | 20110215093 13/044849 |
Document ID | / |
Family ID | 41467014 |
Filed Date | 2011-09-08 |
United States Patent
Application |
20110215093 |
Kind Code |
A1 |
BRUCK; ROLF ; et
al. |
September 8, 2011 |
MODULAR TANK SYSTEM FOR A LIQUID REDUCING AGENT WITH A SUMP ELEMENT
AND MOTOR VEHICLE HAVING THE SYSTEM
Abstract
A modular tank system for a liquid reducing agent includes three
modules. A first module has a tank with a first opening and an
opposite second opening. A second module has a cap element for
holding at least one discharge tube. A third module has a sump
element. The cap element is disposed in the first opening and the
sump element is disposed in the second opening. A motor vehicle
having the modular tank system is also provided.
Inventors: |
BRUCK; ROLF; (BERGISCH
GLADBACH, DE) ; HODGSON; JAN; (TROISDORF, DE)
; REINER; MARTIN; (MURNAU, DE) |
Assignee: |
EMITEC GESELLSCHAFT FUR
EMISSIONSTECHNOLOGIE MGH
LOHMAR
DE
GEIGER AUTOMOTIVE GMBH
GARMISCH-PARTENKIRCHEN
DE
|
Family ID: |
41467014 |
Appl. No.: |
13/044849 |
Filed: |
March 10, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
PCT/EP2009/006538 |
Sep 9, 2009 |
|
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13044849 |
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Current U.S.
Class: |
220/4.12 |
Current CPC
Class: |
F01N 3/2066 20130101;
Y02A 50/20 20180101; F01N 2610/1406 20130101; Y02T 10/24 20130101;
Y02T 10/12 20130101; Y02A 50/2325 20180101; B60K 13/04
20130101 |
Class at
Publication: |
220/4.12 |
International
Class: |
B65D 6/00 20060101
B65D006/00 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 10, 2008 |
DE |
10 2008 046 630.1 |
Claims
1. A modular tank system for a liquid reducing agent, the tank
system comprising: at least three modules including: a first module
having a tank with a first opening and a second opening; a second
module having a cap element disposed in said first opening for
accommodating at least one discharge tube; and a third module
having a sump element disposed in said second opening; said
discharge tube being spatially fixed by said cap element and said
sump element.
2. The modular tank system according to claim 1, wherein said sump
element forms a lowest point of said tank.
3. The modular tank system according to claim 1, wherein said sump
element is formed as a separate plastic part.
4. The modular tank system according to claim 1, wherein said sump
element is welded to said tank with a material bond.
5. The modular tank system according to claim 1, wherein said sump
element has structures reducing movements of the liquid reducing
agent in vicinity of said sump element.
6. The modular tank system according to claim 1, wherein said tank
has a tank bottom, and said sump element has a holder for said
discharge tube, said holder being configured for fixing said
discharge tube at an angle of 45 to 90.degree. to said tank
bottom.
7. The modular tank system according to claim 1, wherein said sump
element has a holder for said discharge tube, and said holder forms
a seat or fitting for said discharge tube.
8. The modular tank system according to claim 1, wherein said sump
element has a holder for said discharge tube, and said holder has a
chamfer allowing said discharge tube to be pushed into said
holder.
9. The modular tank system according to claim 1, wherein said sump
element is formed in one piece.
10. A motor vehicle, comprising: a modular tank system according to
claim 1.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This is a continuation, under 35 U.S.C. .sctn. 120, of
copending International Application No. PCT/EP2009/006538, filed
Sep. 9, 2009, which designated the United States; this application
also claims the priority, under 35 U.S.C. .sctn.119, of German
Patent Application DE 10 2008 046 630.1, filed Sep. 10, 2008; the
prior applications are herewith incorporated by reference in their
entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention:
[0003] The present invention relates to a modular tank system for a
liquid reducing agent which includes a sump element and in which
the tank has three modules. The invention also relates to a motor
vehicle having the modular tank system.
[0004] SCR systems are being used to a greater extent in motor
vehicles due to higher requirements on emissions limits for
pollutants from internal combustion engines. The SCR systems
involve the use of a reducing agent, which must be stored, in
particular in liquid form as a urea/water solution, in separate
tank volumes. The volumes of the tanks for the reducing agent which
are required in such a case are preferably in a range of from 3 to
10 liters, and up to 150 liters in the commercial vehicle sector.
There is therefore a demand for tank shapes which must be matched
to the widely varying spatial conditions in specific motor
vehicles, especially when an SCR system is integrated in a
supplementary manner into a motor vehicle as part of a retrofitting
operation.
[0005] Tanks for liquid reducing agent regularly have discharge
tubes, through which the liquid reducing agent can be discharged
from the tank. The discharge tubes extend into the tank from an
upper region of the latter, thus allowing the tank to be emptied to
the maximum extent and, at the same time, ensuring that seals
required to fix the discharge tube in the tank wall are, where
possible, placed out of the reducing agent. Moreover, the discharge
tube regularly has a heating device, through the use of which
frozen reducing agent, of which there may be at least a small
volume, can be melted and conveyed out of the tank through the
discharge tube.
[0006] The discharge tube has adequate strength, especially with
regard to the possible freezing of the reducing agent, ensuring
that the discharge tube retains its full functionality over many
years of use. In particular, it must be made sufficiently stiff,
thus ensuring that the position of the tank discharge tube remains
fixed. Due to the area of application of SCR systems in motor
vehicles, it is necessary that the components of the system have a
compact construction and, in particular, a diverse construction
regarding the configuration thereof in the motor vehicle.
SUMMARY OF THE INVENTION
[0007] It is accordingly an object of the invention to provide a
modular tank system for a liquid reducing agent with a sump element
and a motor vehicle having the system, which overcome the
hereinafore-mentioned disadvantages and solve some of the
highlighted problems of the heretofore-known systems and vehicles
of this general type. In particular, the intention is to specify a
modular tank system which, due to being produced from different
modules, can be made very diverse for different applications.
Moreover, the modular tank system has a sump element which can be
produced in a simple and economical manner, has a low weight, is
constructed to be suitable for stabilizing the position of a
discharge tube and has an advantageous effect on a discharge
itself. In particular, the aim is to ensure that the sump element
can be used in as large a variety of tank shapes as possible by
virtue of a spatially flexible accommodation of the discharge tube,
thus eliminating costly customized structures of the individual
components for different tank shapes.
[0008] With the foregoing and other objects in view there is
provided, in accordance with the invention, a modular tank system
for a liquid reducing agent. The tank system comprises at least
three modules including a first module having a tank with a first
opening and a second opening, a second module having a cap element
disposed in the first opening for accommodating at least one
discharge tube, and a third module having a sump element disposed
in the second opening. The discharge tube is spatially or
three-dimensionally fixed by the cap element and the sump
element.
[0009] In this configuration, the first opening and the second
opening of the tank are, in particular, round, thus allowing the
cap element and/or the sump element to be turned relative to the
tank. Moreover, there is at least one discharge tube disposed in
the cap element, extending from the cap element into the tank and
being accommodated by the sump element, which is, in particular,
disposed opposite.
[0010] In this case, an opposite configuration of the sump element
and the cap element means, in particular, that they can also be
disposed at an angle relative to one another, in particular in
adjacent wall sections of the tank as well.
[0011] The second module and, in particular, the cap element as
well, preferably have a multi-piece construction and, in addition
to the discharge tube, can accommodate further components, in
particular a return line, which can direct excess reducing agent or
reducing agent which is not needed from the SCR conduit system back
into the tank, plus sensors and, if appropriate, control and/or
measurement electronics. The discharge tube is preferably secured
in the cap element in such a way that an exclusively transverse
movement is required to introduce the discharge tube into the sump
element. In particular, the cap element has a fastening element
that can be rotated relative to the discharge tube and through the
use of which the cap element can be connected to the tank, e.g. by
way of a thread. This makes it possible, on one hand, even for
discharge tubes that are not round or, on the other hand, even for
several components together, to be introduced into the sump
element. Moreover, the cap element has at least one sealing surface
for sealing off the tank relative to the environment of the tank.
In particular, two sealing surfaces are provided, being formed
around the full circumference at different diameters. The cap
element furthermore has at least one metal ring, which is
preferably molded into the cap element. This metal ring is
suitable, in particular, for stabilizing the sealing surfaces of
the cap element in terms of roundness and flatness and making them
durable. A metal ring of this kind is also preferably provided in
the first opening of the tank and/or in the fastening element of
the cap element.
[0012] The sump element is constructed to accommodate and fix the
discharge tube, and it is also possible for other, additional
elements extending through the tank, which are, in particular,
disposed in the cap element, to be accommodated in a manner
comparable to the discharge tube.
[0013] Spatial fixing of the discharge tube is achieved, in
particular, by the fact that, once the cap element and the sump
element have been fastened on the tank, the discharge tube can no
longer be moved by the liquid reducing agent contained in the tank
(due to shocks or the like which occur during operation). In
particular, the discharge tube should remain in the same position
in which it was disposed, even if the reducing agent freezes. Thus
stresses, especially on the cap element and on the tank due to
deflection of the discharge tube, which can lead to leaks in the
tank and/or damage to the components (tank, cap element, sensors,
conduits and electrics), are avoided.
[0014] The modular construction of the tank system makes it
possible to combine various structures of the modules and, in
particular, ensures that it is always possible to use the same
second and third modules with the tank, given different structures
of the first module, and to compensate for any differences in the
position of the second and third modules in the tank through the
use of the modules themselves. This provides not only a significant
reduction in the number of parts while simultaneously allowing a
high degree of adaptability to the spatial conditions in motor
vehicles, but equally also ensures secure fixing and therefore
sustained discharge of the reducing agent in all operating
situations.
[0015] In accordance with another feature of the invention, the
sump element forms the lowest point of the tank. This means, in
particular, that the sump element regularly takes up the volume of
reducing agent when the tank has been largely emptied, thus
enabling the discharge tube to empty the tank, at least almost
completely.
[0016] In accordance with a further feature of the invention, the
sump element is formed as a separate plastic part. For the
(preferred) case where the tank is manufactured from a plastic, the
sump element should preferably be produced from a similar or
identical material. Other potential materials that are preferred
for the sump element and/or the tank are aluminum or stainless
steel, in particular. Plastic is a suitable material for holding
the urea/water solution even over a long period without showing
signs of deterioration. As compared with metal tanks, the plastic
sump element and/or tank are more economical and can be made
lighter in weight.
[0017] In accordance with an added feature of the invention, the
sump element is welded to the tank, yielding a material bond. A
joint of this kind can be produced economically and can regularly
be executed to provide a joint of maximum leak- tightness. This
method of joining is suitable especially for use during the
production of the tank. In this case, however, the position of the
sump element relative to the cap or cover element is fixed and
further modification of the position of the sump element can be
achieved only with considerable effort.
[0018] In accordance with an additional feature of the invention,
the sump element has structures which reduce movements of the
liquid reducing agent in the region of the sump element. This
means, in particular, that the movements occurring during the
operation of the tank system are to a large extent avoided or
reduced. At the same time, the sump element is, in particular,
constructed in such a way that it can hold only a very small volume
of reducing agent in comparison with the tank, having, in
particular, a volume of less than 5% of the tank volume,
particularly preferably less than 1%. This volume, which is small,
is held in a region that is shielded from external flow movements
of the reducing agent in the tank, thus enabling the discharge tube
to convey the reducing agent without air inclusions or other
disruptions. At the same time, this is intended to ensure that any
measuring sensors that may be present can regularly determine
reliable data, especially with regard to temperature, density,
reflectance or refractive index, electrical conductivity and sound
transmission. These values for the reducing agent should not be
distorted by movements of the reducing agent.
[0019] Thus the structures in the sump element are constructed in
such a way that an exchange of volume between the comparatively
small volume of the sump element and that of the tank volume is to
a large extent avoided and that, furthermore, the volume of the
sump element is subdivided in such a way that flow movements are
reduced to a large extent in this area as well.
[0020] In accordance with yet another feature of the invention, the
sump element has a holder for the discharge tube, which holder is
suitable for fixing a discharge tube disposed at an angle of
45.degree. to 90.degree. relative to the tank bottom. In this case,
the angle between the discharge tube and the tank bottom is always
an angle .ltoreq.90.degree. between the center line of the
discharge tube and the region of the tank bottom in which the sump
element is accommodated. This structure of the holder for the
discharge tube and, in particular, the round embodiment of the
first and second openings of the tank, makes it possible to achieve
a large number of tank shapes and positions for the cap element and
the sump element using a standardized cap and sump elements. As a
result, the sump element according to the invention is suitable for
use in virtually all SCR systems, even those that are to be
retrofitted.
[0021] The embodiment, in particular the round embodiment, of the
openings in the tank to accommodate the cap element and the sump
element ensures that the sump element and the cap element can
regularly be aligned in one plane relative to one another, thus
allowing secure fixing of the discharge tube.
[0022] In accordance with yet a further feature of the invention,
the sump element has a holder for the discharge tube, which holder
forms a fit or seat with the discharge tube. In this case, the fit
or seat should be constructed, on one hand, with regard to the
required retention forces and, on the other hand, with regard to
the strength of the discharge tube and of the holder of the sump
element and with regard to the assembly forces for the discharge
tube. In particular, the fit or seat should be embodied as a press
fit, as a transition fit or as a slight clearance fit. The
discharge tube could thus expand, in particular into the sump
element, if the fit were embodied as a transition fit or a slight
clearance fit. This embodiment may be necessary in the case of
tanks with a very rigid structure in order to compensate for
stresses caused by the discharge tube or by the tank itself as a
result of thermal expansion.
[0023] In accordance with yet an added feature of the invention,
the sump element has a holder for the discharge tube, which holder
itself has a chamfer that allows the discharge tube to be pushed
into the holder. In this case, the chamfer serves, in particular,
to enable the discharge tube to be mounted easily and securely in
the sump element, thus eliminating the possibility of damage to the
discharge tube or the cap element during assembly.
[0024] In accordance with yet an additional feature of the
invention, the holder of the sump element for the discharge tube is
constructed in such a way that adequate fixing of the discharge
tube is ensured without using the entire length of the holder of
the sump element. In particular, the holder of the sump element for
the discharge tube has a length of at least 50 mm, preferably at
least 150 mm. The proposed chamfer is, in particular, not included
in these length data. Constructing the holder in this way makes it
possible, in particular, to use discharge tubes of different
lengths and/or tanks with different distances and angles between
the first opening and the second opening. At the same time,
however, care should be taken, in particular, to ensure that the
discharge tube extends far enough into the sump element to allow
reducing agent, that has been calmed in terms of flow, to be
conveyed.
[0025] In accordance with again another particularly preferred
feature of the invention, the modular tank system makes provision
for the sump element to be embodied in one piece. In this case, "in
one piece" means, in particular, that the sump element is composed
of components that are connected to one another at least by a
material bond or can be produced in one step, e.g. by casting
(plastic diecasting). In particular, it is also possible for the
sump element to be embodied in two pieces, with the sump element
and the structures being produced, in particular, from different
materials.
[0026] In accordance with again a further feature of the invention,
a sump element, especially for use in modular tank systems
according to the invention for a liquid reducing agent, is
furthermore proposed.
[0027] With the objects of the invention in view, there is
concomitantly provided a motor vehicle, comprising a modular tank
system according to the invention.
[0028] Other features which are considered as characteristic for
the invention are set forth in the appended claims, noting that the
features presented individually in the claims can be combined in
any technologically meaningful way and reveal further embodiments
of the invention.
[0029] Although the invention is illustrated and described herein
as embodied in a modular tank system for a liquid reducing agent
with a sump element and a motor vehicle having the modular tank
system, it is nevertheless not intended to be limited to the
details shown, since various modifications and structural changes
may be made therein without departing from the spirit of the
invention and within the scope and range of equivalents of the
claims.
[0030] The construction and method of operation of the invention,
however, together with additional objects and advantages thereof
will be best understood from the following description of specific
embodiments when read in connection with the accompanying
drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0031] FIG. 1 is a diagrammatic, side-elevational view of a motor
vehicle with a tank;
[0032] FIG. 2 is a first cross-sectional view of a first sump
element, which is taken along a line II-II of FIG. 3, in the
direction of the arrows;
[0033] FIG. 3 is a second cross-sectional view of the first sump
element, which is taken along a line III-III of FIG. 2, in the
direction of the arrows; and
[0034] FIG. 4 is a cross-sectional view showing a sump element
disposed in a tank.
DETAILED DESCRIPTION OF THE INVENTION
[0035] Referring now in detail to the figures of the drawing for
explaining the invention and the technical field in more detail by
showing particularly preferred structural variants to which the
invention is not restricted and in which identical reference signs
are used for identical objects, and first, particularly, to FIG. 1
thereof, there is seen a diagrammatic side view of a motor vehicle
17 with a modular tank system 26, which has at least three modules.
A first module 4 includes a tank 2 with a first opening 5 and an
oppositely disposed second opening 6. A second module 7 includes a
cap element 8 which, as illustrated therein, has a discharge tube
9, a discharge line 19, a return line 20 and electric leads 21
which, in particular, supply electrical energy to any sensors that
may be present or any control and measurement electronics that may
be required. The tank 2 furthermore has a third module 10 which
includes a sump element 1. In this case, the sump element 1 is
disposed in the region of a tank bottom 13 in the second opening 6.
The second opening 6 is disposed opposite the first opening 5
within the tank 2, enabling the discharge tube 9 to extend from the
cap element 8 to the sump element 1 and be accommodated therein.
The tank bottom 13 and a center line 25 of the discharge tube 9
form an angle 15 therebetween, more details of which will be given
in the description of the other figures. The tank 2 has a tank
volume 23 and the sump element 1 has a volume 24, with the volume
24 being small as compared with the tank volume 23.
[0036] FIG. 2 shows a diagrammatic cross section of a sump element
1 in a first side view, with a discharge tube 9 extending into the
third module 10 of the tank 2, i.e. into the sump element 1. The
sump element 1 represents a lowest point 11 of the tank 2, thus
enabling the discharge tube 9 to empty the tank 2 to the greatest
extent possible. The sump element 1 is furthermore subdivided by
structures 14 which simultaneously form a holder 12 for
accommodating and fixing the discharge tube 9 and are intended to
largely reduce or completely avoid flow movements of a reducing
agent 3. Also provided, in side walls of the sump element 1, are
apertures 18, through which the reducing agent 3 can flow out of
the tank volume 23 of the tank 2 into the volume 24 of the sump
element 1, thus ensuring that the sump element 1 is full as far as
possible, irrespective of the inclination of the tank 2, and holds
the volume 24 of reducing agent 3 in the tank 2 just before
complete emptying. At the same time, the volume 24 of the sump
element 1 is delimited with respect to the tank 2 by the apertures
18 through which the reducing agent 3 can flow into the sump
element 1. The cross-sectional plane of the sump element 1, which
is described below and shown in FIG. 3, is indicated by a section
line III-III.
[0037] FIG. 3 diagrammatically shows the sump element 1 according
to FIG. 2 in a second side view, with the cross-sectional plane in
which the sump element 1 is illustrated in FIG. 2 being indicated
therein by a section line II-II. The discharge tube 9 extends into
the sump element 1 almost as far as the lowest point 11 of the tank
volume 23, which is held by the sump element 1. In this case, the
structures 14 are shown partially sectioned, with the structures 14
in this case at least partially forming the holder 12, through
which the discharge tube 9 is accommodated and fixed in the sump
element 1. The apertures 18, which are furthermore illustrated in
the side walls of the sump element 1 at the level of the tank
bottom 13, are intended to allow the reducing agent 3 to flow out
of the tank volume 23 surrounding the sump element 1.
[0038] FIG. 4 diagrammatically shows the sump element 1 of the
third module 10 in a third side view, with the discharge tube 9 in
this case being disposed at an angle 15 between the center line 25
of the discharge tube 9 and the tank bottom 13. The sump element 1
is connected to the tank 2 or the tank bottom 13 by a flange 22. In
this case, the discharge tube 9 is illustrated with an adapted
shape, thus making almost complete emptying of the volume 24
possible and making it possible to even pump reducing agent 3
contained in the sump element 1 at the lowest point 11 of the tank
2 out of the tank 2. This is not always necessary. In contrast, it
is also possible to provide a standardized discharge tube 9 which
can empty the volume 24 in the sump element 1 at least to a very
large extent. The sump element 1 has a chamfer 16 on the holder 12
thereof for the discharge tube 9, which makes it easier to push the
discharge tube 9 into the sump element 1.
* * * * *