U.S. patent application number 10/578381 was filed with the patent office on 2007-06-28 for heat exchanger, particularly exhaust heat exchanger.
Invention is credited to Peter Kalisch.
Application Number | 20070144157 10/578381 |
Document ID | / |
Family ID | 34559493 |
Filed Date | 2007-06-28 |
United States Patent
Application |
20070144157 |
Kind Code |
A1 |
Kalisch; Peter |
June 28, 2007 |
Heat exchanger, particularly exhaust heat exchanger
Abstract
The invention relates to a heat exchanger, particularly an
exhaust heat exchanger (1) for an internal combustion engine. The
heat exchanger (1) has a tubular housing (2) a housing section of
which is surrounded on the outside by a duct housing (9) with an
annular duct (10) being formed. The duct housing (9) has a coolant
connection (connecting branch 12) and, in the housing section which
is covered by the duct housing (9), passage openings (13 to 16)
which are distributed over the circumference and via which a
uniform distribution of the coolant in the interior of the housing
(2) is obtained. It is advantageous, in the case of a heat
exchanger (1) with an expansion element (18), to use the annular
duct (10) and the passage openings (13 to 16) at the same time in
order to form the expansion element (18).
Inventors: |
Kalisch; Peter;
(Unterensingen, DE) |
Correspondence
Address: |
WILLIAM COLLARD;COLLARD & ROE, P.C.
1077 NORTHERN BOULEVARD
ROSLYN
NY
11576
US
|
Family ID: |
34559493 |
Appl. No.: |
10/578381 |
Filed: |
October 28, 2004 |
PCT Filed: |
October 28, 2004 |
PCT NO: |
PCT/EP04/12206 |
371 Date: |
June 13, 2006 |
Current U.S.
Class: |
60/320 ; 165/163;
165/172 |
Current CPC
Class: |
F02M 26/32 20160201;
F28F 9/0278 20130101; F02M 26/29 20160201; F28F 9/0236 20130101;
F28D 7/163 20130101; F28D 21/0003 20130101 |
Class at
Publication: |
060/320 ;
165/163; 165/172 |
International
Class: |
F01N 5/02 20060101
F01N005/02; F28D 7/02 20060101 F28D007/02 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 8, 2003 |
DE |
103 52 221.2 |
Claims
1-9. (canceled)
10. A heat exchanger for cooling gaseous or liquid media,
particularly an exhaust heat exchanger for an internal combustion
engine, with a tubular housing which has at least one inlet opening
with an adjoining annular duct for the distributed flow of a
cooling medium into the interior of the housing, the annular duct
(10) being formed on the outside of the housing (2) by a duct
housing (9) surrounding a housing section at a distance and the
annular duct (10) being connected to the housing interior via
passage openings (13 to 16) distributed over the circumference of
the housing (2), characterized in that the passage openings (13 to
16) are designed as slots which extend at an axial distance from
one another over part of the housing circumference and, together
with the duct housing (9) having a corrugated tube section (20),
form an expansion element (18).
11. The heat exchanger as claimed in claim 10, wherein next to the
corrugated tube section (20) the duct housing (9) has a cylindrical
housing part (19) which adjoins in the axial direction and on which
the inlet opening (11) with the inlet branch (12) is arranged.
12. The heat exchanger as claimed in claim 10, wherein the housing
(2) is provided at the ends on the longitudinal sides with a
respective flange (3, 4) for the connection of an exhaust pipe, and
in that the expansion element (18) is provided at that end of the
housing (2) which lies on the exhaust gas inflow side (5).
13. The heat exchanger as claimed in claim 10, wherein the duct
housing (2) is designed as a sheet-metal part which is connected
tightly at one end to the housing (2) and at the other end to the
flange (3) on the entry side.
14. The heat exchanger as claimed in claim 10, wherein the
expansion element (18) is surrounded by a protective covering (21).
Description
[0001] The invention relates to a heat exchanger for cooling
gaseous or liquid media, particularly an exhaust heat exchanger for
an internal combustion engine, with a tubular housing which has at
least one inlet opening with an adjoining annular duct for the
distributed flow of a cooling medium into the interior of the
housing.
[0002] A heat exchanger of this type is known from DE 102 38 882 A1
and comprises a tubular housing, in which a nest of tubes is
inserted for the exhaust gas to flow through axially, introduced
coolant washing around the nest of tubes. As a consequence of the
tubes, on the one hand, and the housing, on the other hand, being
subjected to different temperatures, during operation of the
exhaust heat exchanger thermal stresses arise due to different
expansions of the tubes and of the housing. To compensate for
stresses of this type, slots are arranged in the housing and are
sealed to the outside by a duct housing with a corrugated tube
section. This gives rise to an expansion compensating element which
is integrated in the heat exchanger housing.
[0003] The coolant is fed into the housing interior via an inlet
opening introduced radially into the housing, and an annular duct
which follows downstream and through which a uniform distribution
of the coolant flowing into the housing interior is to take
place.
[0004] The annular duct, which is situated within the housing, has
an adverse effect on the cross section through which the flow can
pass, and on the production of the heat exchanger. In addition, it
is also not yet possible for the annular duct on its own to achieve
a circumferential distribution of the coolant that is as uniform as
possible over the housing interior and a largely uniform flow rate
of the coolant in the interior of the housing.
[0005] Furthermore, DE 296 12 361 U1 discloses a further heat
exchanger with an expansion compensating element which is
integrated in the heat exchanger housing, which is composed of
sheet metal.
[0006] The invention is based on the object of developing the heat
exchanger of the generic type in such a manner that, with a
simplified design, a uniform flow, which is distributed over the
circumference of the housing, of coolant into the housing interior
can reliably take place.
[0007] According to the invention, the object is achieved by the
features indicated in the characterizing part of patent claim
1.
[0008] The effect achieved by the arrangement according to the
invention of the annular duct on the outside of the housing is that
the housing interior is no longer adversely affected in terms of
construction space by the annular duct.
[0009] Furthermore, it is possible, by means of a simple
distribution of passage openings in the housing, to obtain a
uniform flow, which is distributed over the circumference thereof,
of coolant into the housing interior.
[0010] In a further refinement of the invention, it is advantageous
if the inlet opening is arranged on the duct housing and has a
connecting branch for a hose line.
[0011] Simple production is achieved if the heat exchanger housing
and the duct housing are produced from one piece, for example by
casting. Irrespective of this, it is also conceivable, however, to
produce the duct housing separately from the heat exchanger
housing, for example from sheet metal, and to connect it tightly
thereto by welding or soldering.
[0012] In a refinement of the heat exchanger with a duct housing
made from sheet metal, it is furthermore advantageous within the
scope of the invention if parts of the heat exchanger housing and
the duct housing are used at the same time in order to form an
expansion element which is customary in the case of heat exchangers
of this type. This creates a heat exchanger which is constructed
compactly and can be produced cost-effectively, since, for example,
a special duct housing for distributing the coolant can be
omitted.
[0013] This is achieved by the duct housing being designed with a
corrugated tube section and the passage openings being designed as
slots which extend partially over the circumference of the heat
exchanger housing at an axial distance from one another. In the
case of the heat exchanger created in this manner, the integrated
expansion element at the same time takes on the function of uniform
distribution of the coolant in the housing interior.
[0014] In order, as far as possible here, to be able to use the
entire length of the heat exchanger housing for the cooling, the
expansion element is arranged with the inlet opening at that end of
the housing which is on the entry side, with a smooth, cylindrical
part of the duct housing being welded or soldered to the heat
exchanger housing, and the adjoining corrugated tube section being
welded or soldered to the flange on the entry side of the
housing.
[0015] The invention is explained in more detail below with
reference to an exemplary embodiment which is shown in the
drawing.
[0016] The single drawing shows, in a perspective illustration,
only the essential parts of a heat exchanger for cooling gaseous
media.
[0017] The heat exchanger illustrated in the exemplary embodiment
is an exhaust heat exchanger 1 for cooling the exhaust gases of an
internal combustion engine, in particular for cooling the exhaust
gases returned in certain operating states to the combustion space
of the internal combustion engine (what is referred to as exhaust
gas recirculation).
[0018] The exhaust heat exchanger 1 has a tubular housing 2 with
respective flanges 3, 4 on the inflow side 5 and on the outflow
side 6. The housing 2 is of U-shape design, and so the flanges 3
and 4 are situated laterally next to each other. The U-shaped
housing parts are connected to one another by means of a tab 7. A
sheet-metal hanger 8 is provided for fastening the heat exchanger 1
to the housing of the internal combustion engine.
[0019] It cannot be seen that a nest of tubes which extends in the
longitudinal direction is arranged in the interior of the heat
exchanger housing 2 and is welded tightly to the housing 2 via
respective tube plates at the housing ends on the longitudinal
sides.
[0020] This gives rise between the housing 2 and the nest of tubes
to a coolant space for coolant for cooling the exhaust gases
flowing through the individual tubes of the nest of tubes
itself.
[0021] In the region of the flange 3 situated on the inflow side 5,
the housing 2 is on the outside by a duct housing 9 which encloses
an annular duct 10 with respect to the housing 2. According to the
exemplary embodiment, the duct housing 9 is composed of sheet metal
and is connected to the heat exchanger housing 2 by welding or
soldering. Within the scope of the invention, the duct housing 2
may also be composed of the same material as the housing 2 and may
be formed as a single piece with it. The duct housing 2 has an
inlet opening 11 with a connecting branch 12 for a coolant
hose.
[0022] Passage openings 13 to 16 are distributed over the
circumference of that part of the housing 2 which is covered by the
duct housing 9. Via the passage openings 13 to 16, the coolant
passed from the connecting branch 11 into the annular duct 10 can
therefore flow in a uniformly distributed manner into the interior
of the housing 2, so that, in addition to a largely uniform
heating, also a largely uniform flow rate of the coolant along the
surface of the tubes through which the exhaust gas flows is
ensured. The discharge of the coolant from the housing 2 takes
place in the vicinity of the flange 4 on the outflow side 6 through
a connecting branch 17.
[0023] According to the exemplary embodiment, the duct housing 9
with the passage openings is part of an expansion element 18
integrated in the housing 2. So that, in addition to supplying
coolant and distributing coolant, the duct housing 2 together with
the passage openings 13 to 16 can carry out the function of
compensating for expansion, the passage openings 13 to 16 are
designed as slots which are in each case arranged over part of the
circumference at an axial distance from one another while the duct
housing 9, which covers the slots to the outside and is composed of
sheet metal, also has, in addition to a smooth, cylindrical housing
section 19 for receiving the connecting branch 12, an additional
corrugated tube section 20 for compensating for expansion.
[0024] So that, as far as possible, the entire length of the
housing 2 can be used for the cooling, the connecting branches 12
and 17 are arranged tightly next to the flanges 3 and 4. This leads
to the expansion element 17 being positioned tightly next to the
flange 3, with the housing section 19 being welded or soldered
directly to the housing 2, and the corrugated tube section 20 being
welded or soldered directly to the flange 3. The duct housing 9 is
protected against external influences by means of a protective
covering 21.
[0025] According to the exemplary embodiment, the subject matter of
the invention is illustrated in the combination of a heat exchanger
with an expansion element. However, in addition to this embodiment,
the invention also comprises an embodiment of a heat exchanger
without an expansion element, in which the duct housing 2 is
designed without the additional corrugated tube section 20 and the
passage openings 13 to 16 are produced as simple holes.
* * * * *