U.S. patent application number 16/630612 was filed with the patent office on 2020-05-28 for a heat exchanger.
This patent application is currently assigned to Valeo Systemes Thermiques. The applicant listed for this patent is Valeo Systemes Thermiques. Invention is credited to Robert Bieniek, Radoslaw Jonczyk, Maciej Klusek, Janus Rod.
Application Number | 20200166296 16/630612 |
Document ID | / |
Family ID | 59350849 |
Filed Date | 2020-05-28 |
United States Patent
Application |
20200166296 |
Kind Code |
A1 |
Klusek; Maciej ; et
al. |
May 28, 2020 |
A HEAT EXCHANGER
Abstract
A heat exchanger comprising a tank (10) and a collector (30)
assembled together, the tank (10) comprising a foot (11) and the
collector (30) comprising a foot receiving surface (33), wherein
the foot (11) comprises a groove (16) in which a gasket (20) is
placed, and which groove (16) is faced by a foot receiving surface
(33) so that together they form a closed cavity within the foot
(11) defining a compression volume for the gasket (20), and wherein
the foot (11) comprises a compression arrangement providing a
filling rate .delta. of the compressed gasket (20) after assembly
less than 100% of the compression volume.
Inventors: |
Klusek; Maciej; (Skawina,
PL) ; Rod; Janus; (Skawina, PL) ; Bieniek;
Robert; (Skawina, PL) ; Jonczyk; Radoslaw;
(Skawina, PL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Valeo Systemes Thermiques |
Le Mesnil Saint Denis Cedex |
|
FR |
|
|
Assignee: |
Valeo Systemes Thermiques
Le Mesnil Saint Denis Cedex
FR
|
Family ID: |
59350849 |
Appl. No.: |
16/630612 |
Filed: |
July 3, 2018 |
PCT Filed: |
July 3, 2018 |
PCT NO: |
PCT/EP2018/067985 |
371 Date: |
January 13, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F28F 2275/122 20130101;
F28D 2021/0082 20130101; F28F 2225/08 20130101; F16J 15/062
20130101; F28F 2230/00 20130101; F28F 21/067 20130101; F28F 9/0226
20130101 |
International
Class: |
F28F 9/02 20060101
F28F009/02; F28F 21/06 20060101 F28F021/06 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 13, 2017 |
EP |
EP17461566 |
Claims
1. A heat exchanger comprising: a tank and a collector assembled
together, the tank comprising a foot and the collector comprising a
foot receiving surface, wherein the foot comprises a groove in
which a gasket is placed, wherein the groove is faced by the foot
receiving surface so that together they form a closed cavity within
the foot defining a compression volume for the gasket, and wherein
the foot comprises a compression arrangement providing a filling
rate of the compressed gasket after assembly less than 100% of the
compression volume.
2. A heat exchanger according to claim 1, wherein the compression
arrangement providing the filling rate of the compressed gasket
after assembly less than 90% of the compression volume.
3. A heat exchanger according to claim 1, wherein the groove
comprises two side walls and a bottom wall.
4. A heat exchanger according to claim 3, wherein the collector
comprises a side flange with crimping tabs crimped onto the foot so
that the side walls press onto the foot receiving surface.
5. A heat exchanger according to claim 1, wherein the compression
arrangement is situated in the groove and comprises a first surface
and a second surface, wherein the first surface is closer to the
foot receiving surface than the second surface.
6. A heat exchanger according to claim 3, wherein the compression
arrangement is situated on the bottom wall of the groove.
7. A heat exchanger according to claim 3, wherein the bottom wall
of the groove comprises a protrusion, protruding towards the foot
receiving surface, and a filling volume.
8. A heat exchanger according to claim 3, wherein side walls of the
groove have surfaces which are parallel to each other.
9. A heat exchanger according to claim 3, wherein the side walls
are flat.
10. A heat exchanger according to claim 7, wherein the filling
volume is divided by the protrusion along the bottom wall of the
groove.
11. A heat exchanger according to claim 1, wherein the compression
arrangement is a separate element attached to the bottom of the
groove in the tanks foot.
12. A heat exchanger according to claim 11, wherein the compression
arrangement complements the shape of the bottom wall and/or the
side walls of the groove in which the compression arrangement is
placed.
13. A heat exchanger, comprising: a tank comprising a foot; a
collector comprising a corresponding foot receiving surface; and a
gasket positioned in between the tank and the collector, wherein
the tank and the collector are assembled together and are
immobilized with respect to each other so that a desired
compression of the gasket is provided, the foot receiving surface
being U-shaped over at least part of a periphery of the collector
and comprising a base, an outer flange and an inner flange
connected to the base, and wherein foot of the tank comprises a
groove for placement of the gasket, which is incorporated to
provide sealing.
Description
[0001] The invention relates to a heat exchanger with a header
tank, particularly for a motor vehicle.
[0002] The invention may be useful in automotive application, more
preferably a radiator or charger air cooler, (CAC), more preferably
a charge air cooler or the like.
[0003] 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.
[0004] 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.
[0005] Instead of housing there can be provided reinforcement
plates on the sides of the heat exchanger.
[0006] 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.
[0007] A collecting tank generally comprises at least two parts: a
collector plate that accepts the ends of the tubes and a tank that
is fixed to the collector plate to close the collecting tank.
All-metal collecting tanks are known as are, alternatively, tanks
with a cover made of plastic.
[0008] The type of collecting tank that has a tank made of plastic
requires a sealing means, conventionally an elastic gasket, to
provide a perfectly sealed joint between the tank and the collector
plate. This may be a case also for all-metal collecting tanks.
[0009] The collector plate may have a groove or slot in which the
sealing means is placed and positioned. The tank cover is then
positioned on the sealing means, after which the tank cover is
fixed to the collector plate to close the collecting tank. The
sealing means, for example a gasket, are disposed therebetween to
provide a fluid-tight seal of the tank-to-collector joint.
[0010] In some known solutions, a gasket is placed between a foot
of a tank and a collector plate. Subsequently, the foot of the tank
is crimped by tabs of the collector plate, thereby sealing the
arrangement. Often the gasket during and after compression is
susceptible to changing its position, which may lead to
deterioration of sealing properties.
[0011] The gasket is made of a material which slightly deforms upon
pressure. Selection of gasket type and material takes into account
many factors, such as its desired placement, chemical resistance,
heat resistance, strength and cost. Exemplary materials of gaskets
utilized to seal a joint between the tank and the collector plate
are elastomers which comprise a certain degree of elasticity.
Different kinds of gaskets are generally used, for example with
circular cross-section or a shaped cross-section.
[0012] Another problem is an excessive filling rate of the gasket
within its placement in the foot of a tank. If a desired level of
gasket compression is to be achieved, e.g. 40% of its diameter (a
percentage of the gasket's original thickness), then the filling
rate of its intended groove may reach 140% (that is, 40% of the
gasket material may escape beyond a groove with analogous volume).
This may lead to undesired displacement of the tank with respect to
the cover plate, and may deteriorate sealing function of the
arrangement in unpredictable rate. The pressure will be exerted
onto the wall of the tank, which may lead to pushing the tank away
from the header plate and partial opening of the crimped tabs
(teeth). Furthermore, if the gasket material is exposed to fluids
(such as engine oil, condensate from EGR), it can swell, which will
further increase the pressing force. If the gasket becomes
excessively compressed, it can be damaged. Excessive filling rate
can also lead to contact between foreign matter and the gasket, for
example salt, condensates, that cause gasket swelling.
[0013] It is therefore an object of the present invention to
provide a heat exchanger with improved sealing.
[0014] The object of the invention has been shown by means of a
drawing, in which:
[0015] FIG. 1 shows an example of a heat exchanger;
[0016] FIG. 2 shows an arrangement according to the invention;
[0017] FIGS. 3a, 3b show an arrangement according to the invention
in a detailed view.
[0018] FIG. 4 presents another example of the invention.
[0019] FIG. 5a-f present further examples of the invention.
[0020] FIG. 1 presents an exemplary heat exchanger. The heat
exchanger comprises a tank 10 and a collector 30 assembled
together, joined for example during crimping. Between them there is
placed a gasket 20. By collector it is meant for example a
collector plate. It can however be also a collector, a flange
etc.
[0021] FIG. 2 shows an arrangement according to the invention. The
tank 10 comprises a foot 11, which is placed inside the receiving
groove of the collector 30. The receiving groove of the collector
30 here is in the shape of a U over at least part of the periphery
of the collector and comprises a base and two flanges 31, 32 these
respectively being an inner flange 31 and an outer flange 32 both
of which are connected to the base. This base is hereinafter
referenced to as a foot receiving surface 33. The outer flange 32
comprises tabs 34, which are designed to be crimped onto the foot
11 of the tank 10, so that the tank 10 and the collector 30 are
immobilized with respect to each other and so that a desired
compression of the gasket 20 is provided. The outer flange 32 of
the collector 30 preferably is continuous around the periphery of
the collector 30. The foot 11 of the tank 10 comprises a groove 16
intended for placement of the gasket 20, which is incorporated to
provide sealing.
[0022] The groove 16 of the tank 10 comprises two side walls 12, 13
and a bottom wall. Preferably, the side walls 12, 13 of the groove
16 are parallel to each other. Preferably, side walls 12, 13 are
flat. The foot receiving surface 33 is then perpendicular to the
side walls 12, 13 of the groove 16.
[0023] As the tabs 34 of the outer flange 32 are crimped over the
tank foot 11, the bottom of the groove 16 is forced down against
the top of the gasket 20 towards the foot receiving surface 33.
These forces cause the gasket 20 to be deformed so that the gasket
20 fills the region between the groove's side walls 12, 13 and the
foot receiving surface 33. Sealing stress is created as the gasket
material pushes out radially against the constraining surfaces of
the foot 11 and the foot receiving surface 33. The groove 16 is
faced by a foot receiving surface 33 so that together they form a
closed cavity within the foot 11 defining a compression volume for
the gasket 20.
[0024] In known solutions, the gasket 20 can extend at least
partially beyond the groove 16 of the foot 11 after assembly and
compression.
[0025] The groove 16 of the foot 11 has been provided with a
compression arrangement, which aims to assure prevention of
excessive filling rate.
[0026] A filling volume provided by the compression arrangement
assures (is configured to provide) gasket filling rate .delta.
inside the groove after assembly at selected level below 100%. More
preferably, this level is .ltoreq.90%, to ensure prevention of
disadvantageous effects of gasket swelling. By means of filling
rate .delta. it is meant a percentage of a groove volume which is
filled by the gasket material after assembly. A compression
arrangement inside groove 16, which provides a desired compression
rate .alpha. of the gasket 20, assures enough free area for gasket
to fill the groove and provide desired filling rate.
[0027] An example of the compression arrangement is a protrusion
14, protruding towards the foot receiving surface 33 from the
bottom wall of the groove 16, accompanied by a filling volume 15
also comprised within said bottom wall.
[0028] FIGS. 3a and 3b present arrangement according to the
invention in a cross-sectional view in a plane perpendicular to the
general run of the groove 16 with the gasket 20. More specifically,
FIG. 3a presents the arrangement with a gasket before assembly, and
FIG. 3b presents the arrangement after assembly, with a compressed
gasket. In FIG. 3a, H_min denotes a distance between the level of
terminal surface 17 of the foot 11, namely surface of the foot 11
in contact with foot receiving surface 33, and the top (terminal
point) of the protrusion 14. D_max denotes a lateral width of the
gasket. In this case, it denotes the diameter of the gasket. W_max
denotes a distance between side walls 12, 13 of the groove 16.
C_max denotes a part of the gasket 20 that would protrude beyond
the groove 16 before compression, after its placement inside the
groove.
[0029] Below there are presented formulas, according to which a
cross-sectional area A.sub.FV of the filling volume 15 of the
groove 16 can be calculated for a groove with flat and parallel
side walls.
H.sub.min=D.sub.max(1-.alpha.) 1)
W.sub.max=D.sub.max(1-.beta.) 2)
A.sub.FV.gtoreq.X*A.sub.G-H.sub.min*W.sub.max 3)
[0030] .alpha. denotes a desired compression rate. In general, it
will be less than 1 (in other words less than 100%). Preferably its
value is 0.4. Other values are also foreseen. Compression rate
depends on requirements of specific project, and can also depend on
specific gasket type.
[0031] .beta. denotes a coefficient selected for ensuring that the
gasket will not fall out of the groove during assembly, by making
the groove equal or slightly narrower than the minimum diameter of
the uncompressed gasket. It is selected after taking into account
assumed tolerances. In general, it will be less than 1. Preferably,
it is selected from values between 0.01 and 0.1. It is to be noted
that the width of the groove does not have to be narrower than the
gasket at whole its length. It can advantageously be narrower, as
described by equation 2, only in selected places along the run of
the groove.
[0032] A.sub.FV denotes a cross-sectional area of the filling
volume 15, which should be provided to achieve filling rate
.delta.<100% at given compression rate .alpha.. A.sub.G denotes
a cross-sectional area of the uncompressed gasket. X denotes a
coefficient which can be selected to ensure the condition. To
satisfy the above-mentioned requirements, X should be greater than
1. It can for example be 1.1.
[0033] Equation 1 allows to calculate the distance between the top
of the protrusion 14 and the level of terminal surface 17 of the
foot 11, which is adjacent the foot receiving surface 33, for a
selected compression rate .alpha..
[0034] Equation 2 allows to calculate distance between side walls
12, 13 of the groove 16, while taking into account a value selected
for ensuring that the gasket will not fall out of the groove during
assembly.
[0035] Equation 3 allows to calculate a cross-sectional area of the
filling volume 15, which should be provided to achieve filling rate
.delta.<100% at given compression rate .alpha..
[0036] In an exemplary embodiment, those values could for example
be:
[0037] D_max=2.9 mm, H_min=1.74 mm, W_max=2.7 mm for .beta.=0.068,
.alpha.=0.4, X=1.1 which would give A.sub.FV=2.56 mm.sup.2.
[0038] The present invention is applicable for tanks made of any
material. Preferably, the protrusion 14 is convex, to facilitate
even distribution of pressure. The filling volume 15 (i.e. the
compression arrangement) can be produced, depending on what
material is used for the tank, by injection technique, machining
technique, as a molded structure. The compression arrangement can
be produced as a separate element, for example comprising a
protrusion and a filling volume as described, attached to the
bottom of the groove in the tank's foot, as shown in FIG. 4. In
such case, the compression arrangement can complement the shape of
the bottom wall and/or the side walls of any groove, preferably any
groove of rectangular cross-section. In other words, the parts of
the attached compression arrangement which do not face the gasket
are in direct contact with the groove.
[0039] Preferably, the filling volume 15 is divided by the
protrusion 14 along the bottom wall of the groove 16.
[0040] FIGS. 5a-5f present another examples of compression
arrangements. In FIG. 5a, the compression arrangement comprises a
protrusion of a convex cross-section, with filling volumes at its
sides. In FIG. 5b, the compression arrangement comprises a
protrusion of a rectangular cross-section, with filling volumes at
its sides. In FIG. 5c, the compression arrangement comprises two
parallel protrusions of arched shape, with a filling volume between
them and filling volumes between the protrusions and side walls of
the groove. In FIG. 5d, the compression arrangement comprises a
series of protrusions of rectangular cross-section, with filling
volumes between them and filling volumes between the protrusions
and side walls of the groove. In FIG. 5e, the compression
arrangement comprises a groove with a filling volume of a concave
cross-section. In FIG. 5f, the compression arrangement comprises a
groove with a filling volume of a rectangular cross-section. In
other words, the compression arrangement can be situated in the
groove 16 and comprise a first surface and a second surface,
wherein the first surface is closer to the foot receiving surface
than the second surface. In yet another words, the distance between
the first surface and the foot receiving surface is smaller than
the distance between the second surface and the foot receiving
surface. Such arrangement of surfaces within the groove allows to
provide a desired filling rate and compression of the gasket. The
first surface provides compression of the gasket, and the second
surface provides a filling volume for the material of the gasket.
The filling volume is selected so as to ensure filling rate below
100%, preferably below 90%.
[0041] Because the side walls 12, 13 of the foot 20 both contact
the foot receiving surface 33, they serve as stoppers. In other
words, the walls of the foot 20 which constitute the groove 16 both
directly contact the foot receiving surface 33. This contact is
ensured to occur without any obstacles. An example of such obstacle
is a fragment of gasket, which has a filling rate .delta. higher
than 100%, that is a gasket part of which escaped from the groove
16 after compression. This direct contact of the side wall 12, 13
with the foot receiving surface 33 of the collector 30 allows to
achieve a precise and defined compression rate .alpha..
[0042] A preferred gasket material is silicone, EPDM. The invention
however applies to gasket of other materials as well.
* * * * *