U.S. patent application number 13/516782 was filed with the patent office on 2013-08-01 for heat exchanger.
This patent application is currently assigned to VALEO SYSTEMES THERMIQUES. The applicant listed for this patent is Paul Garret, Claire Piniarski. Invention is credited to Paul Garret, Eric Piniarski.
Application Number | 20130192803 13/516782 |
Document ID | / |
Family ID | 42937840 |
Filed Date | 2013-08-01 |
United States Patent
Application |
20130192803 |
Kind Code |
A1 |
Garret; Paul ; et
al. |
August 1, 2013 |
HEAT EXCHANGER
Abstract
The invention relates to a heat exchanger including exchange
components and fluid flow components (2, 2', 3), at least one fluid
collecting tank (11, 11') into which the exchange components open
out (2, 2', 3), at least one collecting plate (10) for holding the
exchange components (2, 2', 3) and a housing (4) for accommodating
the exchange components (2, 2', 3). The exchanger is characterized
in that it includes a flange (5) for fixing the collecting tank
(11, 11') on the housing (4). Thanks to the invention, the
transmission of stresses from the flange (5) to the collecting
plate (10) is avoided, which means that a thinner collecting plate
(10) is able to be formed.
Inventors: |
Garret; Paul; (Veneux Les
Sablons, FR) ; Piniarski; Eric; (Bazancourt,
FR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Garret; Paul
Piniarski; Claire |
Veneux Les Sablons
Bazancourt |
|
FR
FR |
|
|
Assignee: |
VALEO SYSTEMES THERMIQUES
Le Mesnil-Saint-Denis
FR
|
Family ID: |
42937840 |
Appl. No.: |
13/516782 |
Filed: |
December 2, 2010 |
PCT Filed: |
December 2, 2010 |
PCT NO: |
PCT/EP2010/068768 |
371 Date: |
February 1, 2013 |
Current U.S.
Class: |
165/151 |
Current CPC
Class: |
F28F 9/0226 20130101;
F28D 21/0003 20130101; F28D 1/0233 20130101; F28D 1/05333 20130101;
F28F 2275/122 20130101; F28F 9/0219 20130101; F28D 7/1684
20130101 |
Class at
Publication: |
165/151 |
International
Class: |
F28D 1/02 20060101
F28D001/02; F28D 1/053 20060101 F28D001/053 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 18, 2009 |
FR |
0906151 |
Claims
1. A heat exchanger including exchange components and fluid flow
components, comprising: at least one fluid collecting tank into
which the exchange components open out; at least one collecting
plate for holding the exchange components; and a housing for
accommodating the exchange components, wherein said heat exchanger
includes a flange for fixing the collecting tank to the
housing.
2. The exchanger as claimed in claim 1, in which the flange and the
collecting plate are fixed to the housing independently of each
other.
3. The exchanger as claimed in claim 1 in which the flange and the
collecting plate is fixed directly to the housing.
4. The exchanger as claimed in claim 1, wherein the flange and the
collecting plate do not contact each other.
5. The exchanger as claimed in claim 1, wherein the exchange
components include tubes, within which a first fluid is
flow-connected to the tank, and around which flows a second fluid,
wherein the collecting plate provides a sealing between the first
fluid and the second fluid and the flange provides a sealing
between the first fluid and the outside of the exchanger.
6. The exchanger as claimed in claim 1, wherein the collecting tank
and the flange are crimped to each other.
7. The exchanger as claimed in claim 1, wherein the flange is
brazed to the housing and the housing includes at least one
locating lug designed to be accommodated in an opening in the
flange to hold this latter on the housing whilst both parts are
being brazed.
8. The exchanger as claimed in claim 1, in which the collecting
tank and the housing are crimped.
9. The exchanger as claimed in claim 1, wherein the collecting
plate is brazed to the housing.
10. The exchanger as claimed in claim 9, in which the collecting
plate includes a skirt with an area along which the collecting
plate is brazed to the housing.
Description
[0001] The invention relates to a heat exchanger.
[0002] A heat exchanger, for example used in the car industry and
more exactly in a heat combustion engine in a motor vehicle,
includes heat exchange components and fluid flow components in
which the fluids circulate exchanging heat between them. The heat
exchange components can comprise, for example, tubes, plates, fins
and flow agitators, etc. Numerous structural configurations are
conceivable. For example, the exchanger can comprise a core of
tubes arranged in parallel one with respect to the other in one or
several rows which are also parallel, said tubes being designed to
convey a first fluid, whilst a second fluid flows between the tubes
and exchanges heat with the first fluid. Numerous fluid
associations can be conceived, whether they be liquids and/or
gases.
[0003] The exchanger includes a housing for receiving the tubes,
said housing including a plurality of walls forming the volume in
which the tubes are received. It is generally open at its two ends
so that the tubes can be connected to the fluid collection or
distribution tanks also called collecting tanks: one input
collecting tank and one output collecting tank. The first fluid
flows in the tubes from the input collecting tank toward the output
collecting tank. The second fluid flows around the tubes, from an
input pipe toward an output pipe, and exchanges heat with the first
fluid.
[0004] The exchanger generally also includes two collecting plates
for holding the tubes, the fluid collecting tanks being mounted on
the collecting plates. The tubes pass through openings arranged in
the collecting plates and open out into the fluid collecting
tanks.
[0005] Generally, the collecting plates are fixed to the housing
and the collecting tanks are fixed to the collecting plates, for
example by crimping. To this end, each collecting plate includes
means allowing an edge of the collecting tank with which it is
associated to be crimped thereto. Such a fixing method for the tank
is known, for example, from document WO 2008/125309 or also from
document EP 2,031,338 in which the collecting plate is in two parts
which are joined mechanically.
[0006] In certain engines, there are constraints on the available
space in the area in which the exchanger has to be mounted;
consequently it is necessary to produce exchangers respecting these
constraints. These constraints can mean, for example, that
relatively flat exchangers have to be produced. To this end,
flattened tubes are provided but with a sufficiently large cross
section to present the fluid with a passage cross section adapted
to the desired flow. Such tubes have a streamlined cross section;
typically, they can have a rectangular cross section with the
dimensions 100 mm.times.7 mm. Moreover, in applications where, for
example, water, which is a good heat-conveying fluid, circulates
between the tubes, it is preferable for the spacing between
successive tubes to be small, for example equal to 2 or 3 mm or
less.
[0007] Consequently, it is necessary to manufacture the collecting
plates with elongated openings separated by small width walls, said
width corresponding to the spacing between successive tubes. In
this case, the walls separating the openings have very great cross
sectional slenderness, that is to say that they are very elongated
in one direction but slim in the two other directions.
Consequently, the question of how they are manufactured arises. It
is known that for the manufacture of collecting plates, punching
processes with so-called "straight edge blanking", allow
inter-opening walls thinner than the thickness of the plate to be
realized from a relatively thick plate; for example, openings which
are 60 mm in length can be formed in a plate which is 4 mm thick
with inter-opening walls with a width approximately equal to 2.6
mm. Nevertheless, when forming a collecting plate with openings
which are 100 mm in length and inter-opening walls of 2 mm, it is
not possible to implement a punching process with straight edge
blanking. Consequently, it is advisable to use a classic chasing
process; in this case, the thickness of the plate must be less than
the width of the inter-tube walls and, for the above case, a plate
with a very thin thickness of between 0.8 mm and 1 mm is
recommended. Now, if the collecting tank has to be crimped by the
collecting plate, this latter must have sufficient mechanical
strength to fulfill this function. Consequently, a dilemma is faced
as if the thickness of the collecting plate is increased (by taking
it for example to 1.5 or 2 mm) it becomes impossible to implement a
classic chasing process. It thus seems difficult to be able to
provide a large cross sectional slenderness for the tubes since it
is necessary to ensure a sufficient thickness for the collecting
plate.
[0008] The object of the invention is to propose a design allowing
for the formation of a collecting plate with openings with a large
cross sectional slenderness.
[0009] It is noted that the invention arises from the resolution of
this problem but is not limited to this single application, the
invention also providing advantages in its application to
collecting plates with openings with a more reasonable cross
sectional slenderness.
[0010] It is thus that the invention relates to a heat exchanger
including exchange components and fluid flow components, at least
one fluid collecting tank into which the exchange components open
out, at least one collecting plate for holding the exchange
components and a housing for accommodating the exchange components,
characterized in that said heat exchanger includes a flange for
fixing the collecting tank to the housing.
[0011] Thanks to the invention, the functions of holding the tubes
and holding the collecting tank have been decoupled: two distinct
parts (the collecting plate on the one hand and the flange on the
other hand) fulfill these functions. Thus, it is possible to
provide a collecting plate with a small thickness (typically 0.8
mm) with openings with great cross sectional slenderness; in this
way tubes with a streamlined cross section can be formed and
therefore a flattened exchanger which takes up little space. The
function of holding the collecting tank is ensured by the flange,
in an independent manner. Moreover, the ease of assembly of such an
exchanger is preserved, each part being fixed, independently of
each other (that is to say without direct stress transmission
between them), to a common component, namely, in this case, the
housing.
[0012] According to one embodiment, the flange and the collecting
plate are fixed to the housing independently of each other.
[0013] According to one embodiment, the flange and/or the
collecting plate is fixed directly to the housing. In this way, the
compactness of the exchanger is increased.
[0014] According to one embodiment, the flange and the collecting
plate do not contact each other. In this way, the lack of direct
transmission of stresses between said two parts, which are not only
not fixed to each other but also do not contact each other, is
ensured in an even better manner.
[0015] According to one embodiment, the exchange components include
the tubes within which a first fluid (for example a gas) is
flow-connected to the tank and around which flows a second fluid
(for example a liquid), the collecting plate fulfils a sealing
function between the first fluid and the second fluid and the
flange fulfils a sealing function between the first fluid and the
outside of the exchanger.
[0016] According to one embodiment, the collecting tank and the
flange are crimped to each other.
[0017] According to one embodiment, the flange is brazed to the
housing. Such a fixing method is sturdy and not expensive.
[0018] According to one embodiment in this case, the housing
includes at least one locating lug designed to be accommodated in
an opening in the flange to hold this latter on the housing whilst
both parts are being brazed.
[0019] Preferably in this case, the opening is arranged in the
bottom of the groove for accommodating the housing.
[0020] According to one embodiment, the locating lug is designed to
be crimped against the fixing wall to hold it in the opening.
[0021] According to one embodiment, the locating lug is designed to
be deformable to hold it in the opening.
[0022] According to one embodiment, the collecting tank and the
housing are crimped.
[0023] According to one embodiment, the collecting plate is brazed
to the housing.
[0024] According to one embodiment, the collecting plate includes a
skirt with an area along which it is brazed to the housing. In this
way, there is a large contact surface, which ensures the parts are
well brazed.
[0025] The overall cross sectional shape of the pipes is preferably
rectangular, the ratio of length to width of which is preferably in
excess of 5.
[0026] The invention applies particularly well to an air-water
exchanger, for example a water cooler for recirculated exhaust
gases or a charge air cooler for a heat combustion engine of a
motor vehicle
[0027] The invention will be better understood by way of the
following description of the preferred embodiment of the exchanger
of the invention, with reference to the sets of accompanying
drawings, in which:
[0028] FIG. 1 shows a perspective view of a first embodiment of the
exchanger of the invention, with the fluid collecting tanks fixed
to its flanges;
[0029] FIG. 2 shows a detail (from above) in FIG. 1;
[0030] FIG. 3 shows a perspective sectional view in the plane of
the height and the length of the exchanger in FIG. 1;
[0031] FIG. 4 shows a perspective sectional view in the plane of
the length and the width of the exchanger in FIG. 1, without a
collecting tank;
[0032] FIG. 5 shows a partially exploded perspective view of the
exchanger in FIG. 1, without a collecting tank;
[0033] FIG. 6 shows a perspective end view, from below, of the
exchanger in FIG. 1, without a collecting tank;
[0034] FIG. 7 shows a cross section of a corner of the exchanger in
FIG. 1;
[0035] FIG. 8 shows a perspective view and partially from the back
of a corner of the exchanger in FIG. 1;
[0036] FIG. 9 shows a perspective cross sectional view, partially
from the back of a corner of the exchanger in FIG. 1;
[0037] FIG. 10 shows a perspective view, from above, of a corner of
the collecting tank of the exchanger in FIG. 1;
[0038] FIG. 11 shows a perspective view, from the inside, of a
corner of the exchanger in FIG. 1;
[0039] FIG. 12 shows a perspective sectional view in the plane of
the length and the width of a second embodiment of the exchanger of
the invention;
[0040] FIG. 13 shows a perspective view of a third embodiment of
the exchanger of the invention;
[0041] FIG. 14 shows a schematic cross sectional view in the plane
(L, h) of a fourth embodiment of the exchanger of the
invention;
[0042] FIG. 15 shows a schematic cross sectional view in the plane
(L, h) of a fifth embodiment of the exchanger of the invention.
[0043] With reference to the figures and more particularly to FIGS.
1 to 6, a heat exchanger 1 according to a first embodiment includes
heat exchanging components 2, 2', 3, a housing 4 for receiving or
accommodating said components 2, 2', 3, an air inlet collecting
tank 11 and an air outlet collecting tank 11'. The housing 4
includes the openings 6, 7 for connecting to the pipes 8, 9 for the
flow of water, in this particular case an inlet pipe 9 and an
outlet pipe 8, connected to a water circuit in which the exchanger
1 is mounted. In the embodiment described, the different components
of the exchanger 1 are brazed to each other, except for the tanks
11, 11' which are crimped; such exchangers with their components
brazed or crimped are well known by the person skilled in the art
as far as their general characteristics are concerned.
[0044] The exchanger 1 describes a so-called "air-water" exchanger,
that is to say an exchanger in which the fluids which exchange heat
are air and water. It is, for example, a water cooler for so-called
"recirculated" exhaust gases of a heat combustion engine for an
automotive vehicle or perhaps a charge- air cooler for such an
engine; the water is preferably so-called <<low
temperature>> water from the cooling circuit of said engine;
it is typically glycolized water.
[0045] With reference to FIG. 1, the overall form of the exchanger
1 is a parallelepiped. Conventionally and to simplify its
description, the direction L is defined by the length of the
exchanger 1, which is its largest dimension, and the direction in
which the fluids flow, the direction 1 by the width of the
exchanger 1 and the direction h by its height (or thickness).
Subsequently, the direction of said dimensions will be mixed up
with their value; in other words, L, 1 or h will indicate
respectively equally well the length, the width and the height of
the exchanger 1 or the direction of the length, the direction of
the width and the direction of the height of the exchanger 1.
Moreover, in the figures, a Cartesian reference (L, 1, h) is formed
on the basis of these perpendicular directions together.
Furthermore, the ideas of external (or outside) and internal (or
inside) used in the description refer to the relative positions of
the components compared to the outside or inside of the exchanger
1.
[0046] With reference to FIG. 3, the exchange components include
the flattened tubes 2 for the flow of air. Their large dimension
(which is the overall direction of the flow of air within them) is
parallel to the direction of the length L of the exchanger 1 and
their cross section transversally with respect to this length L is
rectangular in shape; the rectangle, the cross section of each tube
2 being in this form, has a dimension parallel to the width 1 of
the exchanger 1 and a dimension parallel to the height h of the
exchanger 1. Each tube 2 has a length appreciably equal to the
length L of the exchanger 1 and a width appreciably equal to the
width 1 of the exchanger 1; its dimension parallel to the height h
of the exchanger 1 (this is its thickness) is less than the height
of the exchanger 1 and, in this particular case, is relatively
small, which gives the tubes 2 their flattened form. By way of
example, the thickness of the tubes 2 can be equal to approximately
7 or 8 mm for each tube 2, the width 1 of the tubes 2 being equal
to approximately 100 mm. Moreover, the inter-tube spaces (that is
to say the ducts 3 for the flow of water) can, for example, be of a
dimension (parallel to the height h of the exchanger 1) that is
less than 3 mm, for example is appreciably equal to 2 mm. The
exhanger 1 is compact in this way. The tubes 2 are assembled in
parallel with each other, all the tubes 2 forming a stack in the
direction of the height h of the exchanger 1; this is also referred
to as a core of tubes; the dimension of the entire core in parallel
with the height h of the exchanger 1 is appreciably equal to the
height h of the exchanger 1. The tubes 2 are each assembled
respectively in parallel with one another, and allow the
circulation of air within them, overall in the direction of the
length L of the exchanger.
[0047] Fins T for agitating the air flow are mounted in the tubes 2
allowing the heat exchanges between the air and the water to be
facilitated through the walls of the tubes 2. Said fins 2' are well
known to the person skilled in the art and it is not necessary to
describe them in detail; in this case they have an undulating form
and their cross section, when seen in an end view in the axis of
the length L of the exchanger 1, is in the form of a coil between
the walls of each tube 2.
[0048] The water flow agitators (not shown) are mounted in the
water flow ducts 3 arranged between the tubes 2, said flow
preferably being against the current, that is to say in the
opposite direction to the direction of flow of the air. The
agitators are in the form of plates which extend appreciably over
the entire lateral area of the tubes 2 (the lateral area is the
area of the tubes 2 defined by the dimensions parallel to the
length L and to the width 1 of the exchanger 1) and in all the
space between successive tubes 2 to which they are brazed;
agitators are also provided between the end tubes 2 and the walls
of the housing 4. The shape of the agitators creates the turbulence
in the flow of water passing across them in order to promote the
heat exchanges, in a known manner.
[0049] As alluded to further above, the exchanger 1 includes, at
each of its ends (in the dimension of its length L), an air
collecting tank 11, 11'. On the right-hand side (in FIG. 1), this
is the air inlet collecting tank 11 and, on the left-hand side, the
air outlet collecting tank 11'. The ends of the air circulation
tubes 2 are connected to the air collecting tanks 11, 11', the
inside volume of the tubes 2 thus being flow-connected to the
inside volume of the collecting tanks 11, 11'; in other words, the
tubes 2 open out into the collecting tanks 11, 11'. The collecting
tanks 11, 11' are connected to the pipes of an air circuit in which
the exchanger 1 is mounted. The air is introduced into the tubes 2
by means of the air inlet collecting tank 11 and is collected
leaving the tubes 2 by the air outlet collecting tank 11'.
[0050] The structure of the exchanger will be described in more
detail by its connection to the inlet tank 11. The description
given applies equally to the exchanger at its output tank 11'. The
input 11 and output tanks 11', in this particular case, are similar
and are mounted symmetrically; obviously, according to another
embodiment, they can be different.
[0051] The exchanger 1 includes at its end a collecting plate 10,
the function of which is to hold the tubes 2 in position, to guide
the flow of air between the inside volume of the collecting tank 11
and the tubes 2 and to prevent water flowing toward the inside
volume of the collecting tank 11, while preventing flows of air and
water converging; in other words, the collecting plate 10 ensures
the seal between the air and the water. The person skilled in the
art often refers to the collecting plate 10 using the term
collector 10 and it will be designated as such below.
[0052] The collector 10 is fixed to the housing 4, in this
particular case by means of brazing, at an area of a peripheral
edge. More precisely in this particular case, the collector 10
includes a peripheral skirt 10a having a lateral area along which
the collector 10 is brazed to the housing 4; this allows for
simpler positioning between said two parts before they are brazed
but also for a better hold between the two since the contact area
(and therefore the brazing area) is larger than if the collector 10
were brazed along an edge.
[0053] The peripheral skirt 10a is formed by the edge of the
collector 10 which is bent over, in this particular case along its
entire periphery. The skirt 10a therefore extends perpendicularly
with respect to the overall plane of the plate forming the
collector 10, in parallel, therefore, with the direction of the
length L of the exchanger 1. The skirt 10a can be bent over in one
direction (as in FIG. 3) or in the other (as in FIG. 12), in other
words toward the outside or toward the inside of the exchanger 1,
respectively; the bending side depends notably on the space
available and on the spacing between the collector 10 and the
flange 5 described below.
[0054] With reference to FIG. 5, the collector 10 is in the form of
a plate mounted transversely with respect to the length L of the
exchanger 1 in order to receive the ends of the tubes 2. The
collector 10 is perforated by a plurality of openings 12, each
opening 12 being associated with a tube 2. The form of each opening
12 corresponds to the cross section of a tube 2 and is edged by the
walls 13 or collars 13 or rims 13 containing the end of the tubes 2
and holding these latter in position; the collars, moreover,
fulfill a function of stiffening the collector 10. Said collars 13
extend overall perpendicularly with respect to the overall plane of
the plate forming the collector 10, therefore in parallel to the
direction of the length L of the exchanger 1, the end 13'
projecting from said collars 13 being directed toward the inside of
the exchanger 1; in this way, the collars 13 extend from the
collector 10, around the tubes 2, fitting tightly around the ends
of said tubes. The ends of the tubes 2 are slipped into said
collars 13, forming a slide in order to fit tightly around them;
each collar 13 forms a contact area with the area of the end of the
tube 2 which is associated therewith, allowing them to be brazed to
each other. The tubes 2, brazed in this way to the collars 13
edging the openings 12 of the collector 10, are fixed in position.
The ends of the tubes 2 are thus separated from each other by the
collars 13, the separating spaces between the successive tubes 2
define the ducts 3 for the flow of water. As the collars 13 are
brazed to the ends of the tubes 2 and, in a transversal manner,
(compared to the direction of the length L of the exchanger 1) fill
all the space between them, said collars 13 prevent the water from
flowing into the volume of the collecting tank 11; furthermore,
said collars 13 also prevent the water from flowing into the tubes
2. This type of collector 10 is well known to the person skilled in
the art and it is not necessary to describe it in any more
detail.
[0055] In the embodiment shown, the housing 4 includes two walls
15, 16 being formed into an L. In other words, each wall 15, 16 has
a cross section (compared with the direction of the length L of the
exchanger 1) in the shape of an L. Each wall 15, 16 is formed into
an L by bending around an edge to form two vanes (15a, 15b), (16a,
16b) perpendicular with respect to each other. The idea of the
walls 15, 16 in the shape of an L is their simplicity of
manufacture and storage in view of the manufacture of the
exchangers (storage being possible simply by assembling the walls
together one on top of another).
[0056] More precisely, each wall 15, 16, in this case, includes a
large vane 15a, 16a and a small vane 15b, 16b. The large vane 15a,
16a is in the form of a rectangular plate with dimensions
appreciably equal to the length L of the exchanger 1 and to its
width 1, whilst the small vane 15b, 16b is in the form of a
rectangular plate with dimensions appreciably equal to the length L
of the exchanger 1 and to its height h. The concepts of large and
small vanes are introduced here to allow each of the vanes (15a,
15b), (16a, 16b).of each wall 15, 16 to be designated in a distinct
manner
[0057] The water inlet 9 and outlet pipes 8 into and out of the
exchanger 1 are connected here to a same side of the exchanger 1,
in this particular case to the small vane 16b of the second wall
16.
[0058] The walls 15, 16 of the housing 4 are fixed to each other
around the exchange components 2, 2', 3; in this particular case,
they are brazed. To this end, each wall 15, 16 includes, at the
free end of its small vane 15b, 16b, a raised edge 15c, 16c, which
is an edge 15c, 16c to be fixed to the large vane 16a, 15a of the
other wall 16, 15. Said raised edge 15c, 16c extends
perpendicularly with respect to the small vane 15b, 16b, from an
edge of the bend by means of which it is connected thereto.
Crimping lugs R are arranged to ensure the connection between the
raised edges 15c, 16c and the corresponding large vanes 16a, 15a.
Brazing allows the contact areas to be locked together and held one
against the other.
[0059] Once the walls 15, 16 have been fixed, the vanes (15a, 15b),
(16a, 16b) of the walls 15, 16 formed into an L form the four
lateral sides of the exchanger 1 (lateral sides are referred to
with regard to the direction of its length L).
[0060] It is remembered here that in the embodiment described, the
collector 10 is fixed to the housing 4 by means of brazing. More
precisely, the outside area of its peripheral skirt 10a is brazed
to the internal area of the vanes (15a, 15b), (16a, 16b) of the
walls 15, 16.
[0061] One particular characteristic of the walls 15, 16 will be
described now with reference to FIG. 7. Close to the contact zone
between the raised edge 15c, 16c of the small vane 15b, 16b of each
wall 5, 16 and the large vane 16a, 15a of the other wall 16, 15,
there is a zone where there is a clearance with the rounded corner
of the collector 10 (said two clearances diagonally opposite on the
exchanger 1 are shown by the same reference J). Because of the
existence of said clearances J, there is a risk of water leaking
there. This is the reason why each wall 15, 16 includes a sealing
portion P close to each of the free corners of its large vane 15a,
16a. Each sealing portion P is in the form of a portion protruding
out of the inside area of the large vane 15a, 16a of the wall 15,
16, in the direction of the tubes 2; said protruding portion P is
in the form of a corner or a fin. Such a protruding portion P can
either be chased on the wall 15, 16 subsequently to its
manufacture, or can be directly formed during the manufacture of
the wall 15, 16. Once the contact areas have been brazed, the seal
is thus assured at said sealing portion P.
[0062] It is noted that the walls 15, 16 each include two widenings
E, respectively, in the direction of the height h of the exchanger
1, arranged close to each end of its large vane 15a, 16a. Said
widenings E are formed here by chasing the wall 15, 16. They are
provided as the dimensions of the collector 10 are greater, in the
direction of the height h of the exchanger 1, than the dimension of
the small vanes 15b, 16b of the walls 15, 16 in an L; these are
therefore the widenings E (or stampings E) for accommodating the
collector 10. Said stampings E have an additional advantage:
insofar as they accommodate the collectors 10 in the direction of
the height h of the exchanger 1, they form a stop in the dimension
of the length L of the exchanger 1; thus, they form axial holding
means (in this direction L) for the collectors 10 and therefore for
all the exchange components 2, 2' whilst all the components of the
exchanger 1 are being brazed.
[0063] Furthermore, the exchanger 1 includes a flange 5 for fixing
the collecting tank 11 to the housing 4. Said flange 5 is brought
onto the housing 4. It is fixed (in this particular case by means
of brazing) to the end of the housing 4, along the periphery of
said housing; this is therefore a peripheral flange 5, with an
overall rectangular form, in this particular case formed from one
single part. It is fixed to the housing 4 independently of the
collector 10 and is not fixed to this latter; in other words, the
exchanger 1 does not include any means for fixing the flange 5 to
the collector 10.
[0064] The flange 5 includes an internal longitudinal wall 17 (in
the direction of the length L) which extends along its entire
periphery; said internal longitudinal wall 17 is arranged in order
to extend from the internal side of the walls 15a, 15b, 16a, 16b of
the housing 4 and to be brazed to them.
[0065] The internal longitudinal wall 17 is bent out toward the
outside and in the direction of the exchanger 1, thus forming an
internal transverse wall 18 and an intermediate longitudinal wall
19 providing, with the internal longitudinal wall 17, a peripheral
groove G1 for accommodating the walls 15a, 15b, 16a, 16b of the
housing 4, fulfilling a function of fixing the housing 4 in this
way. The internal transverse wall 18 forms a stop for the end of
the walls 15a, 15b, 16a, 16b of the housing 4.
[0066] The intermediate longitudinal wall 19 is bent out toward the
outside and in the opposite direction of the bend forming the
peripheral groove G1, thus forming an external transverse wall 20
and an external longitudinal wall 21 providing, with the
intermediate longitudinal wall 19, a peripheral groove G2 for
accommodating a side edge 11a of the end of the collecting tank 11,
fulfilling a function of fixing the collecting tank 11 in this way;
this is the end of the tank 11 by means of which it is fixed to the
flange 5; the side edge 11a of the tank 11 will be called the
fixing edge 11a.
[0067] Thus, the flange includes two peripheral grooves G1, G2
formed by the walls 17, 18, 19, 20, 21 of the flange 5, said
grooves G1, G2 including a common wall 19. Each groove G1, G2 is
provided for holding a part, in this particular case for holding
the housing 4 and the collecting tank 11, respectively. More
precisely, the housing 4 and the collecting tank 11 are each
arranged so that their longitudinal end walls (in the direction of
the length L of the exchanger 1) are inserted longitudinally into a
peripheral groove G1, G2, by means of the transverse opening in
said groove G1, G2. The grooves G1, G2 are oriented in opposite
directions, that is to say that their openings are turned in two
opposite directions in the direction of the length L of the
exchanger 1. On account of their structure with a common wall 19,
they provide the exchanger 1 with great compactness and a high
level of hold for the parts 4, 11, whether this be in view of their
brazing (for the housing 4) or in view of their crimping (for the
collecting tank 11). Indeed, the collecting tank 11 and the housing
4 are fixed to each other in a compact manner without actually
being fixed directly to each other, which ensures that the assembly
is sturdy and notably allows for good stress transmission.
[0068] In the extension of the external longitudinal wall 21, the
flange 5 includes lugs 22 for crimping the tank 11 to the flange 5.
Said lugs 22 are arranged so as to be hooked (bent over) on the
fixing edge 11a. The crimping lugs 22 are shown bent over (that is
to say in the crimping position) in all the figures. The tank 11 is
therefore crimped to the flange 5.
[0069] With reference in particular to FIG. 4, the exchanger 1, in
this particular case, is arranged so that the collector 10 is fixed
to the housing 4 at a spacing d from the flange 5 and more
precisely from the free end 17a of its internal longitudinal wall
17.
[0070] The holding of the tubes 2 is ensured by the collector 10
and the holding of the collecting tank 11 is ensured (by crimping)
by the flange 5, itself brazed to the housing 4, the collector 10
and the flange 5 both being brazed to the housing 4 but, in this
case, independently of one another; in this particular case, they
do not even contact one another. In this way, the stresses to which
the flange 5 is subjected on account of its function of holding the
collecting tank 11 are not transmitted directly to the collector 11
which is connected to the housing 4 and to the tubes 2.
[0071] Insofar as the stresses applied to the flange 5 are not
transmitted to the collector 11, this latter can be formed so as to
be able to receive the tubes 2 with a streamlined cross section and
separated from each other by a small spacing. In particular, it is
possible to form the collector 11 by means of a traditional chasing
process on plate with a very thin thickness; in such a process, the
collars 13 of the collector 11 are stamped then their bottom is
punched in order to form the openings, in a known manner. By way of
example, as the plate allowing the collector 10 to be formed has a
thickness of approximately 1 mm, a collector 10 can be formed with
openings 12 of 100 mm by 7 or 8 mm approximately, with an
inter-tube space of 2 to 3 mm. The space occupied (dimension
parallel to the direction of the length L of the exchanger 1) by
the collars 13 can be appreciably equal to 4 mm; in this way, by
removing the thickness of the straps 14 (1 mm), the collars 13 have
a useful area for the application of the end of the tubes 2 and for
brazing thereto of approximately 3 mm.
[0072] Furthermore, as the collector 10 is brazed directly to the
housing 4, the radius of its corners is relatively large and the
collector 10 is simpler to manufacture, which is of interest as, on
account of the thickness of the collector 10, it is not always easy
to form it correctly.
[0073] One additional advantage is that, industrially, the
invention can be implemented with collectors of the prior art,
which are thin but not very strong, simply by adding a flange
5.
[0074] The openings 23 for receiving the locating lugs 24
protruding longitudinally out of the vanes 15a, 15b, 16a, 16b of
the housing 4 are arranged in the internal transverse wall 18 of
the flange 5 (that is to say in the bottom of the groove G1). Each
lug 24 extends in the extension of the vane 15a, 15b, 16a, 16b
supporting it; one vane 15a, 15b, 16a, 16b can include one or
several lugs 24; all the vanes 15a, 15b, 16a, 16b or just some of
them can include one or several lugs 24. In this particular case,
the exchanger 1 includes one locating lug 24 located in the middle
of the end of each small vane 15a, 16a of the housing 4 and two
locating lugs 24 located at the end of each large vane 15b, 16b of
the housing 4.
[0075] The locating lugs 24 are arranged so as to be able to be
bent over or deformed so as to hold the flange 5 in position in
relation to the housing 4 by means of crimping. The function of
their deformation is also to ensure they are brazed perfectly to
the inside areas of the openings 23 into which they are inserted so
as to take up the mounting clearance with said areas and to avoid
any air escaping here, in other words to ensure the sealing of the
openings 23. To this end, the lugs 24 can be bent over against the
internal transverse wall 18, for example by resting on this latter
itself abutting against the end edge of the vanes 15a, 15b, 16a,
16b of the housing 4. They can also simply be deformed rather than
crimped, inasmuch as simple deformation would preclude any movement
in relation to the flange 5.
[0076] The function of said lugs 24 is to allow the positioning and
the holding of the flange 5 on the housing 4 during the manufacture
of the exchanger 1 and in particular before and during the brazing
of its various constituent components.
[0077] The manufacture of the exchanger 1 is made easier in this
way. The tubes 2 are stacked and inserted into the openings of the
collectors 10 and the L-shaped walls 15, 16 of the housing 4 placed
around them and held in position one with respect to another thanks
to the crimping lugs R; it can be noted here that other holding
means such as clinching means could be provided. The flanges 5 are
moved to the ends of the housing 4, the locating lugs 24 being
inserted into the openings 23 provided for this purpose and
deformed, bent over or crimped to ensure the holding of the
assembly. Everything can then be brazed and is placed in a furnace
for this purpose, in a known manner. The areas intended to be
brazed to the housing 4 (and notably the outside areas of the
skirts 10a of the collectors 10 and the areas of the grooves G1)
have consistent dimensions, which allows for quality brazing, the
contact areas being large. The input 11 and output collecting tanks
11' can then be crimped to the exchanger 1, in this particular case
whilst arranging a seal ring 27 in the bottom of the groove G2
receiving the fixing edge 11a of the tank 11, in a known manner;
this is an O-ring 27 which is shown schematically in FIGS. 3 and
9.
[0078] One particular characteristic of the exchanger 1 can be seen
in FIGS. 3, 5, 6 and 8 to 11: the corners of the flange 5 include a
pushed-in portion 25 at the internal groove G1.
[0079] Such a pushed-in portion 25 is provided for facilitating the
manufacture of the flange 5 and for promoting the quality of its
brazing on the housing 4, by ensuring a sufficient brazing area
including in the corners. Indeed, the flange 5, in this particular
case, is formed by chasing and it is difficult to bend the material
in the corners, as is known. Thus, thanks to the pushed-in portions
25, the quantity of material in the corners is less great, which
allows them to be chased in such a way so as to form an internal
longitudinal wall which has, including in the corners, sufficient
length to enable quality brazing to the housing 4.
[0080] Obviously, the shape of the housing, and more particularly
the shape of the corners of the ends of the housing 4, is adapted
to the shape of the flange 5, as can be seen, for example, in FIG.
5 (the ends of the housing 4 being intended to abut against the
internal groove G1 of the flange 5).
[0081] The collecting tank 11 includes, at each corner, a swelling
26 corresponding to the pushed-in portion 25 of the flange 5. Said
swelling 26 is accommodated in the pushed-in portion 25, ensuring a
function of holding the seal ring 27 in position; indeed, the seal
ring 27 would not be contained in the corners on account of the
pushed-in portions 25 of the flange 5.
[0082] The second, third, fourth and fifth embodiments of the
flange 5 of the exchanger 1 can be seen in FIGS. 12, 13, 14 and 15.
Their description will be concise and the references used for the
preceding embodiment will be kept, with the exception of certain
ones where an extra mark is added to underline the most notable
differences.
[0083] In the second embodiment shown in FIG. 12, the form of the
skirt 10a of the collector 10 is slightly different: it can be seen
that it is not bent over toward the collecting tank 11 as was the
case in the first embodiment but is bent over on the other side, in
the direction of the other end of the exchanger 1. Whichever way,
the collector 10 has an external area of peripheral skirt at which
it is brazed to the internal area of the walls of the housing 4, in
this particular case at a spacing d from the free end 17a of the
internal longitudinal wall 17 of the flange 5.
[0084] In the third embodiment shown in FIG. 13, two
particularities can be noted. First of all, the flange 5 does not
include a pushed-in portion in the corners. Furthermore, the walls
15, 16 of the housing 4 include, at their ends, an edge 28 bent
over at 90.degree. with respect to the plane of the walls 15, 16;
the function of said bent-over edges 28 is to act as a stop for the
flange 5 when it is mounted on the housing 4 in order to ensure it
is properly positioned with regard to its brazing.
[0085] In the fourth embodiment shown in FIG. 14, the tubes 2 and
the collector 10 can be identical to those described previously.
The peripheral flange 5 only has one single groove G, formed by an
internal longitudinal wall 17', a transverse wall 18' and an
external longitudinal wall 19' and in which the edge 11a of the
tank 11 is accommodated with a seal ring 27. The edge 11a is
crimped in said groove G by the lugs 22 bent over it. The flange 5
is brazed to the walls of the housing 4 by the outside area of its
external longitudinal wall 19'. In this way, the edge 11a of the
tank 11 is held on the inside of the housing 4 and not on the
outside as in the preceding embodiment. The choice between said two
embodiments will be made, therefore, as a function of the
constraints on available space for the positioning of the exchanger
1.
[0086] In the fifth embodiment shown in FIG. 15, the tubes 2 and
the collector 10 can be identical to those described previously.
The peripheral flange 5 only has one single groove G', formed by an
internal longitudinal wall 17'', a transverse wall 18'' and an
external longitudinal wall 19'' and in which the edge 11a of the
tank 11 is accommodated with a seal ring 27. The flange 5 is brazed
to the walls of the housing 4 by the outside area of its external
wall 19''. Furthermore, the edge 11a of the tank 11 is crimped not
by the flange 5 but by the housing 4, by the lugs 22' formed on the
end of said housing 4 and bent over on it. In this way, the edge
11a of the tank 11 is held on the inside of the housing 4 and is
crimped by this latter, the flange 5 for fixing the tank 11 on the
housing allowing stresses to be taken up and notably the collector
10 to be protected during the crimping of the housing 4 to the edge
11a of the tank 11, without the stresses being transmitted to it
since it is fixed to the housing 4 independently of the flange 5
and, in this particular case, is arranged at a spacing from this
latter, without contacting it.
[0087] The operation of the exchanger 1 (whatever its embodiment)
is as follows (it is described in a concise manner as it is well
known by the person skilled in the art). Air is supplied to the air
input tank 11, flows in the tubes 2 (said flow being agitated by
the fins 2') and leaves the exchanger 1 again by means of the air
outlet tank 11'. Furthermore, water is supplied to the exchanger
through the water inlet pipe 9, circulates in the water flow ducts
3 (said circulating being agitated by means of the agitators) and
leaves the exchanger 1 again by means of the water outlet pipe 8.
The flows of air and water are counter-directional in the direction
of the length L of the exchanger 1; this is called a
"countercurrent" heat exchanger; the efficiency of such an
exchanger 1 is very good.
[0088] The heat exchanger 1 has been described in connection with
air circulating in its tubes 2 and water circulating between the
tubes by means of the agitators. It goes without saying that this
could be reversed, that is to say water in the tubes and air
between the tubes. Furthermore, it could also be air in both cases
or water in both cases, or other fluids.
[0089] The invention has been described in connection with
preferred embodiments, but it goes without saying that other
embodiments are conceivable. In particular, the characteristics of
the different embodiment described can be combined together, if
there are no incompatibilities.
* * * * *