U.S. patent application number 11/795217 was filed with the patent office on 2008-08-07 for evaporator, in particular for an air-conditioning system of a motor vehicle.
Invention is credited to Jens Hadler, Michael Kohl, Dieter Schmadl, Wolfgang Seewald, Christoph Walter, Eberhard Zwittig.
Application Number | 20080184732 11/795217 |
Document ID | / |
Family ID | 36128369 |
Filed Date | 2008-08-07 |
United States Patent
Application |
20080184732 |
Kind Code |
A1 |
Hadler; Jens ; et
al. |
August 7, 2008 |
Evaporator, in Particular for an Air-Conditioning System of a Motor
Vehicle
Abstract
The invention relates to an evaporator (1), in particular for an
air-conditioning system of a motor vehicle, comprising flow
channels for a coolant and ribs which can be impinged upon by air
and which are arranged on the outside of the flow channels.
According to the invention, at least one cooling element (5) which
can be cross-flown by a coolant (5) is connected in a thermally
conductive manner to the evaporator (1) and is connected to a
secondary circuit (6) which acts as a cooler for the consumers, in
particular electronic components (8).
Inventors: |
Hadler; Jens; (Stuttgart,
DE) ; Kohl; Michael; (Bietigheim, DE) ;
Schmadl; Dieter; (Marbach, DE) ; Seewald;
Wolfgang; (Stuttgart, DE) ; Walter; Christoph;
(Stuttgart, DE) ; Zwittig; Eberhard; (Hochdorf,
DE) |
Correspondence
Address: |
WOODARD, EMHARDT, MORIARTY, MCNETT & HENRY LLP
111 MONUMENT CIRCLE, SUITE 3700
INDIANAPOLIS
IN
46204-5137
US
|
Family ID: |
36128369 |
Appl. No.: |
11/795217 |
Filed: |
January 16, 2006 |
PCT Filed: |
January 16, 2006 |
PCT NO: |
PCT/EP06/00318 |
371 Date: |
July 13, 2007 |
Current U.S.
Class: |
62/503 |
Current CPC
Class: |
F28D 2021/0085 20130101;
B60H 1/00271 20130101; F25B 2309/06 20130101; F28D 1/0461 20130101;
B60H 2001/00307 20130101; F28D 2021/0031 20130101; B60H 2001/00614
20130101; F25B 9/008 20130101; F28D 7/0008 20130101; F25B 25/005
20130101; F28F 3/12 20130101; F28D 1/05391 20130101; B60H
2001/00949 20130101; B60H 1/00885 20130101; F25B 39/022
20130101 |
Class at
Publication: |
62/503 |
International
Class: |
F25B 39/02 20060101
F25B039/02 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 14, 2005 |
DE |
DE102005002060.7 |
Oct 13, 2005 |
DE |
DE102005409406.4 |
Claims
1. An evaporator, especially for an air-conditioning system of a
motor vehicle with flow channels for a refrigerant and with fins,
arranged outside of the flow channels and that can be impinged upon
by air, characterized in that at least one cooling element (5, 11,
21, 210, 510, 520, 710) that can carry a coolant flow is connected
in a heat conductive way to the evaporator (1, 10, 20, 270, 570,
770).
2. The evaporator according to claim 1, characterized in that the
evaporator is constructed as a flat tube evaporator (10, 20, 30,
270, 570, 770) with flat tubes (10a, 31, 81, 220, 230) and
corrugated fins (10b, 82).
3. The evaporator according to claim 1, characterized in that the
evaporator is constructed as a plate or tray evaporator.
4. The evaporator according to claim 1, characterized in that the
refrigerant is R134a or R152.
5. The evaporator according to claim 1, characterized in that the
refrigerant is R744 (carbon dioxide).
6. The evaporator according to claim 1, characterized in that the
one or more cooling elements (5, 11, 21, 22, 35, 80) are arranged
between two adjacent flat tubes (10a, 81) or trays or plates.
7. The evaporator according to claim 1, characterized in that the
one or more cooling elements (5, 11, 21, 22, 35, 80, 210, 510, 520,
710, 910) are connected to at least one flow channel (10a, 31, 81,
220) with a material fit, especially through soldering, welding,
adhesion, etc., or especially with a positive fit through clips,
screws, etc.
8. The evaporator according to claim 1, characterized in that the
cooling element (5, 11, 21, 22, 35, 60, 70, 80) is connected on the
coolant side to a separate cooling circuit (secondary circuit
6).
9. The evaporator according to claim 8, characterized in that the
secondary circuit (6) is used for cooling loads generating heat,
especially electronic components.
10. The evaporator according to claim 1, characterized in that the
coolant in the secondary circuit (6) is a mixture of water and
Glysantin.
11. The evaporator according to claim 1, characterized in that the
one or more cooling elements (5, 11, 21, 22, 35, 60, 70, 80, 210,
510, 520, 710, 910) are constructed as rectangular tubes (61, 71)
and are arranged between adjacent flow channels (81).
12. The evaporator according to claim 1, characterized in that the
one or more cooling elements (80) contact the flow channels (81)
with both broad sides.
13. The evaporator according to claim 1, characterized in that the
one or more cooling elements (80) are arranged between a flow
channel (81) and a corrugated fin (82).
14. Evaporator according to claim 1, characterized in that the one
or more cooling elements (80) are arranged between two adjacent
corrugated fins (82).
15. The evaporator according to claim 1, characterized in that the
one or more cooling elements (70) can carry a single flow of
coolant.
16. The evaporator according to claim 1, characterized in that the
cooling element (69) can carry a double flow (with reversal U).
17. The evaporator according to claim 1, characterized in that the
one or more cooling elements (60, 70) have an inlet and an outlet
port (60a, 60b, 70a, 70b) for the coolant.
18. The evaporator according to claim 1, characterized in that
turbulence inserts (64, 72) are arranged in the interior of the
cooling element (60, 70).
19. The evaporator according to claim 1, characterized in that the
one or more cooling elements (210, 410, 520, 710, 910) are
connected to at least one outer flat tube (220) with a material
fit, especially through soldering, welding, adhesion, etc., and/or
especially with a positive fit through clips, screws, etc.
20. The evaporator according to claim 1, characterized in that at
least one first cooling element (510) and at least one second
cooling element (520) can carry a flow in series.
21. The evaporator according to claim 1, characterized in that at
least one first cooling element (710) and at least one second
cooling element (710) can carry a flow in parallel.
22. The evaporator according to claim 1, characterized in that at
least one cooling element (210, 510, 520, 710, 910) replaces at
least one side part of the evaporator (270, 570, 770) and in
particular delimits the tube block (370).
23. The evaporator according to claim 1, characterized in that a
width (390) of the one or more cooling elements (210, 510, 520,
710, 910) is independent of at least one modular dimension of at
least one tube, especially a flat tube, and/or at least one fin,
especially a corrugated fin.
24. The evaporator according to claim 1, characterized in that a
width (390) of the one or more cooling elements (210, 510, 520,
710, 910) is dependent on at least one modular dimension of at
least one tube, especially a flat tube, and/or at least one fin,
especially a corrugated fin.
25. A cooling device for cooling loads generating heat, especially
in a motor vehicle, characterized by the heat-conductive connection
of at least one cooling element that can carry a coolant flow to an
evaporator, especially of a motor vehicle air-conditioning system,
and the connection of a secondary circuit that can carry a flow of
coolant to the one or more cooling elements according to one of the
preceding claims.
26. Use of an evaporator, especially of a motor vehicle
air-conditioning system, as a heat sink for cooling of loads
generating heat.
Description
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] This application is a National Stage filing of International
Application PCT/EP2006/000318, filed Jan. 16, 2006, claiming
priority to German Application No. 10 2005 002 060.7, filed Jan.
14, 2005 and also claiming priority to German Application No. 10
2005 049 406.4, filed Oct. 13, 2005, entitled "EVAPORATOR, IN
PARTICULAR FOR AN AIR-CONDITIONING SYSTEM OF A MOTOR VEHICLE". The
subject application claims priority to PCT/EP2006/000318 and to
German Application Nos. 10 2005 002 060.7 and 10 2005 049 406.4,
and all three references are expressly incorporated by reference
herein, in their entirety.
BACKGROUND OF THE INVENTION
[0002] The invention relates to an evaporator, especially for an
air-conditioning system of a motor vehicle.
[0003] Evaporators for motor vehicle air-conditioning systems are
known in various constructions as mechanically joined round tube
systems and also perforated flat tube, plate, or tray heat
exchangers. A perforated, double-row flat-tube evaporator is known
through DE 198 26 881 A1 by the applicant, wherein corrugated fins
are arranged between the flat tubes which are impinged upon by
surrounding air that is cooled in the evaporator and fed into the
inner compartment of the vehicle. The evaporator is embedded in a
refrigerant circuit of the air-conditioning system and carries a
flow of refrigerant (R134a). A perforated tray evaporator is known,
for example, from DE 198 14 050, wherein corrugated fins that can
be impinged upon by surrounding air are also arranged here between
the trays. The evaporator is arranged in an air-conditioning device
within an air channel.
[0004] There is a plurality of electronic components or units in
the motor vehicle that generate heat and therefore must be cooled.
Here, surrounding air is usually used as the coolant. In DE 89 14
525 U1 by the applicant, an electronic component is cooled by the
air flow drawn in by a fan, wherein the cover of the fan is formed
as a cooling body. Another possibility for cooling electronic
components is known by the applicant through DE 37 03 873 A1,
wherein a cooling body is made from a base body with a fin package
connected with a material fit, upon which cooling air impinges. The
cooling body is connected to the electronic unit with its base body
in a heat-conductive way.
[0005] Another cooling device, for cooling electronic components
through convection, is proposed by the applicant in DE 198 06 978
A1, wherein the cooling body has corrugated fins that are impinged
upon by a cooling air flow.
[0006] For increasing the cooling effect, a cooling device is
proposed in DE 41 31 739 A1 having a hollow space that carries a
flow of cooling fluid for heat transfer. The hollow space has
turbulence inserts for increasing the heat transfer and is
connected to the electronic unit via a base plate in a heat
conductive way.
[0007] A similar cooling device for electronic components is
proposed by the applicant in DE 199 11 205 A1, wherein a hollow
space carries a flow of a liquid coolant that is removed from and
fed back to a coolant radiator of a motor vehicle cooling
circuit.
[0008] Finally, in DE 199 11 204 A1 by the applicant, a cooling
device for electronic components is proposed wherein the components
are connected directly to a coolant radiator of a motor vehicle in
a heat-conductive connection, for example, arranged on the side
parts or the coolant box of the radiator. The heat to be discharged
thus flows directly into the coolant of the radiator via heat
conduction.
[0009] A disadvantage in the known proposals mentioned above is
that the heat that can be discharged is limited by the existing
temperature of the coolant, whether it is an air flow or a liquid
flow. In particular, at high outside temperatures, both the cooling
air flow and also a coolant flow removed from the coolant radiator
have a relatively high temperature. Thus, the cooling power is also
limited.
[0010] The task of the present invention is to create a device for
cooling loads generating heat, especially in a motor vehicle and
preferably for electronic components, which allows a higher cooling
power.
[0011] This task is solved as described and claimed herein.
According to the invention, an evaporator, especially in a motor
vehicle air-conditioning system, is used for cooling purposes, and
at least one cooling element is implemented in the evaporator that
can carry a coolant flow. The cooling element is located in
heat-conductive contact with the evaporator, especially with its
flow channels guiding the refrigerant, so that the heat absorbed by
the coolant can be released to the refrigerant, which has a
relatively low temperature in the evaporator. The cooling element
is connected to a cooling circuit, a so-called secondary circuit,
guiding the coolant that absorbs heat from loads to be cooled and
transports it to the evaporator, which acts as a heat sink. The
evaporator itself is not changed in its operation, thus there is
also no intervention in the refrigerant circuit of the
air-conditioning system. In principle, any type of evaporator is
possible as a heat sink for the cooling according to the invention,
but preferably flat tube, plate, or tray evaporators are used that
offer smooth surfaces for connection to the cooling element
according to the invention. Soldering the cooling element to parts
of the evaporator, whereby an especially good heat transfer is
achieved, is advantageous. Also, the refrigerant flowing through
the evaporator is arbitrary, i.e., either a conventional
refrigerant, such as R134a, or an alternative refrigerant, such as
R744 (carbon dioxide) can be used. CO.sub.2 evaporators also offer
good possibilities for integrating at least one cooling element
according to the invention.
[0012] In one advantageous construction of the invention, the
cooling element or elements integrated into the evaporator can
carry a flow of coolant, preferably a water-Glysantin mixture, and
are connected to a separate cooling circuit, a secondary circuit.
Individual loads generating heat, e.g., electronic components, are
assigned to this secondary circuit, with the coolant of the
secondary circuit being led past these components. Here, cooling
bodies known from the state of the art mentioned above can be used.
The cooling element according to the invention is preferably
constructed as a rectangular tube, i.e., box-shaped, wherein it
preferably takes up the space between two adjacent flat tubes,
plates, or trays. This space is taken up by a corrugated fin in
standard evaporators. The cooling element thus takes the place of
the corrugated fin and fills its space, wherein--as mentioned--the
heat conduction can be increased considerably through soldering.
Alternatively, the cooling element can also be arranged between two
corrugated fins or between a flat tube (tray or plate) and one
corrugated fin, and soldered to these parts.
[0013] In another advantageous construction of the invention, the
cooling element can carry one or more flows, i.e., it can carry a
flow of coolant in two or more directions with reversal, whereby
the cooling power can be influenced in this way. For increasing the
heat transfer, turbulence inserts can be provided that can also be
soldered to the walls of the cooling element. The cooling element
is connected on the coolant side to the secondary circuit via an
inlet and outlet port, wherein the coolant can be circulated by a
pump.
[0014] In another construction, the evaporator has at least one
cooling element that is connected to at least one outer flat tube
with a material fit, especially through soldering, welding,
adhesion, etc., and/or especially with a positive fit through
clips, screws, etc. In this way, a side part, especially two side
parts, of the evaporator are advantageously eliminated and costs
are reduced. Advantageously, the width of the cooling element can
be selected arbitrarily according to the required cooling power and
is not dependent on the modular dimensions of tubes, especially
flat tubes, and/or fins, especially corrugated fins.
[0015] In another construction, the evaporator has at least one
first cooling element and at least one second cooling element which
can carry a flow, especially advantageously in series.
[0016] In another construction, the evaporator has at least one
first cooling element and at least one second cooling element which
can carry a flow in parallel.
[0017] In another advantageous construction, at least one cooling
element replaces at least one side part of the evaporator and
delimits, in particular, the tube block. Therefore, in an
especially advantageous way, at least one part, especially two
parts, are eliminated, and thus the costs are advantageously
reduced. The cooling element is flush with at least one of the
collecting tanks in another advantageous construction and is
connected, in particular, to at least one of the collecting tanks
with a material fit, especially through soldering, welding,
adhesion, etc. In another advantageous construction, the cooling
element does not terminate flush with at least one collecting tank
and is not connected to at least one collecting tank.
[0018] In another advantageous construction, at least one cooling
element of the evaporator has a width that is independent of at
least one modular dimension of at least one tube, especially a flat
tube, and/or at least one fin, especially a corrugated fin.
[0019] In another advantageous construction, at least one cooling
element of the evaporator has a width that is dependent on at least
one modular dimension of at least one tube, especially a flat tube,
and/or at least one fin, especially a corrugated fin.
[0020] According to an advantageous improvement of the invention, a
cooling device with a secondary circuit is provided that can be
alternatively connected to the engine cooling circuit of a motor
vehicle or to a heating body arranged in the engine cooling
circuit. In this way, the advantage is achieved that the secondary
cooling circuit is redundant in case of a failed air-conditioning
system. The coolant of the secondary circuit is then cooled in the
heating body, through which there is a flow of air. The cooling of
the electronics can thus be maintained. In an advantageous
construction, the heating body is connected or disconnected by
means of thermostatic valves or electrically controllable
multi-port valves. In another advantageous construction, a
controllable short circuit is provided between the feed and return
line of the secondary circuit, whereby condensation can be
prevented.
[0021] In another advantageous construction of the invention, an
additional heat exchanger, which is connected to a secondary
circuit for cooling loads, especially electronic components, is
connected downstream on the air side of the evaporator of a motor
vehicle air conditioning system. The additional heat exchanger,
preferably a serpentine heat exchanger, is cooled by the cold air
leaving the evaporator and thus acts as a heat sink for the
secondary cooling circuit. Advantageously, the additional heat
exchanger, which has a relatively small depth in the direction of
air flow, can be installed between the evaporator and heating body
of a conventional air-conditioning system, without requiring
additional installation space.
[0022] Embodiments of the invention are shown in the drawing and
are defined in more detail below.
BRIEF SUMMARY
[0023] An evaporator (1), in particular for an air-conditioning
system of a motor vehicle, comprising flow channels for a coolant
and ribs which can be impinged upon by air and which are arranged
on the outside of the flow channels. According to the invention, at
least one cooling element (5) which can be cross-flown by a coolant
(5) is connected in a thermally conductive manner to the evaporator
(1) and is connected to a secondary circuit (6) which acts as a
cooler for the consumers, in particular electronic components
(8).
[0024] One object of the present disclosure is to describe an
improved evaporator for the air-conditioning system of a motor
vehicle.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0025] FIG. 1 is a refrigerant circuit with an evaporator according
to the invention with a secondary circuit.
[0026] FIGS. 2, 2a illustrate a flat tube evaporator according to
the invention with integrated cooling element.
[0027] FIGS. 3, 3a illustrate a flat tube evaporator with two
integrated cooling elements.
[0028] FIGS. 4, 4a illustrate an evaporator for an alternative
refrigerant (CO.sub.2) with integrated cooling element.
[0029] FIGS. 5, 5a, 5b, 5c illustrate a cooling element that can
carry double flow.
[0030] FIGS. 6, 6a illustrate a cooling element that can carry
single flow.
[0031] FIG. 7a illustrates a cooling element that can carry double
flow.
[0032] FIGS. 7b, c, d illustrate a cooling element that can carry
single flow.
[0033] FIGS. 8a, 8b, 8c, 8d, 8e illustrate various arrangements of
cooling elements in the evaporator.
[0034] FIG. 9a illustrates a front view of a flat tube evaporator
with cooling elements arranged on the outside on the evaporator
block.
[0035] FIG. 9b illustrates an isometric representation of a flat
tube evaporator with cooling elements arranged on the outside on
the evaporator block.
[0036] FIG. 9c illustrates a cooling element that can carry double
flow.
[0037] FIG. 10a illustrates a front view of a flat tube evaporator
with cooling elements arranged on the outside on the evaporator
block.
[0038] FIG. 10b illustrates an isometric representation of a flat
tube evaporator with cooling elements arranged on the outside on
the evaporator block.
[0039] FIG. 10c illustrates an isometric representation of a flat
tube evaporator with cooling elements arranged on the outside on
the evaporator block.
[0040] FIG. 10d illustrates a cooling element that can carry single
flow.
[0041] FIG. 11a illustrates a rear view of a flat tube evaporator
with cooling elements arranged on the outside on the evaporator
block.
[0042] FIG. 11b illustrates an isometric representation of a flat
tube evaporator with cooling elements arranged on the outside on
the evaporator block.
[0043] FIG. 11c illustrates a cooling element that can carry single
flow.
DETAILED DESCRIPTION
[0044] For the purposes of promoting an understanding of the
disclosure, reference will now be made to the embodiments
illustrated in the drawings and specific language will be used to
describe the same. It will nevertheless be understood that no
limitation of the scope of the disclosure is thereby intended, such
alterations and further modifications in the illustrated device and
its use, and such further applications of the principles of the
disclosure as illustrated therein being contemplated as would
normally occur to one skilled in the art to which the disclosure
relates.
[0045] FIG. 1 shows a double-row flat tube evaporator 1, which is
connected on the refrigerant side to a refrigerant circuit 2 of a
not-shown motor vehicle air-conditioning system. In addition to the
evaporator 1, there is a condenser 3 and a compressor in the
refrigerant circuit. The evaporator 1 corresponds in its
construction essentially to the state of the art mentioned above
(DE 198 26 881 A1 by the applicant) and carries a flow of
conventional refrigerant (R134a). The evaporator 1 thus has a block
1a consisting of non-designated flat tubes and corrugated fins, as
well as top and bottom collecting tanks 1b, 1c. In the center
region of the block 1a, a cooling element 5 is implemented in the
evaporator 1 that is connected to a secondary circuit 6. In the
secondary circuit 6, a cooling body 7, which is connected in a heat
conductive way to an electronic component 8 to be cooled, is
arranged as an example of a load. The cooling element 5, secondary
circuit 6, and cooling body 7 carry a flow of coolant, preferably a
liquid coolant, a water-Glysantin mixture, wherein the coolant can
be circulated by a not-shown pump. In the secondary circuit 6,
which thus acts as a cooling circuit, other not-shown loads can be
arranged that are also cooled by the coolant flow. The cooling
element 5 outputs the heat absorbed by the coolant to the
evaporator or the refrigerant, i.e., the evaporator 1 acts as a
heat sink for the cooling circuit 6. The primary function of the
evaporator, to cool air for the interior of the vehicle, is not
negatively affected by the connection of the secondary circuit 6.
There is also no intervention into the refrigerant circuit 2.
[0046] FIGS. 2 and 2a show a flat tube evaporator 10 in a view from
the front as well as in a 3D representation. The evaporator 10 has
flat tubes 10a, between which there are corrugated fins 10b that
are impinged upon by the surrounding air. In the middle region of
the evaporator 10 between two flat tubes 10a there is a cooling
element 11 that is heat conductively connected, preferably through
soldering, to the flat tubes 10a. The cooling element 11 has an
inlet port 11a and an outlet port 11b for connecting to the
secondary or coolant circuit (cf. secondary circuit 6 in FIG. 1),
not shown here, in its bottom region (in the drawing). The flat
tube evaporator 10 has a refrigerant connection flange 10c which is
connected on one side to a not-shown refrigerant circuit of the
motor vehicle air-conditioning system, and on the other side to the
evaporator 10 or its collecting tanks via connection tubes 10d,
10e. The evaporator 10 carries a flow of air in the direction of
the arrow L, which is cooled in the evaporator and is fed to a
not-shown passenger compartment of the motor vehicle.
[0047] FIGS. 3 and 3a show another embodiment of the invention in
the form of a flat tube evaporator 20, in a view from the front and
in an oblique representation. The construction of the flat tube
evaporator 20 corresponds essentially to the construction of the
evaporator according to FIGS. 2 and 2a with the difference that
here two cooling elements 21, 22 are integrated into the evaporator
block, i.e., each between two adjacent flat tubes. The cooling
elements 21, 22 correspond in their construction to the cooling
element 11 according to FIGS. 2, 2a, i.e., they also have
connection ports 21a, 21b and also 22a, 22b. Both cooling elements
21, 22 are also connected to the secondary circuit, not shown here.
By multiplying the number of cooling elements, the cooling capacity
of the secondary circuit is increased accordingly--but at the cost
of the secondary-side heat exchange surface area (corrugated fins)
of the evaporator.
[0048] FIGS. 4 and 4a show another embodiment of the invention in
the form of an evaporator 30, in a view from the front and in a 3D
representation. The evaporator 30 corresponds essentially also to
the state of the art and is operated with an alternative
refrigerant, CO.sub.2 or R744, which means a pressure-tight
construction for the individual evaporator components. The
evaporator 30 has U-shaped or serpentine-shaped flat tubes 31
(preferably multiple-chamber tubes), between which are arranged
corrugated fins, not shown here. The evaporator 30 is connected via
connection tubes 32, 33 to a not-shown CO.sub.2 refrigerant circuit
of a motor vehicle air-conditioning system, wherein the connection
tubes 32, 33 each transition into a distributor or collection tube
32', 33'. The distribution of the refrigerant is performed in a
collecting tank 34, which is shown in FIG. 4a in an exploded view.
This evaporator type is also known from the state of the art, for
example, DE 102 60 030 A1 by the applicant. Other constructions for
evaporators operated with CO.sub.2 are known through DE 100 25 362
A1. A cooling element 35 is integrated in the evaporator 30,
approximately in the middle region, and arranged between two
adjacent flat tubes 31, i.e., preferably soldered together with the
adjacent flat tubes. The cooling element 35 has connection ports
35a, 35b in its lower region for connection to the secondary
circuit mentioned above that serves to cool loads generating
heat.
[0049] FIGS. 5, 5a, 5b, 5c show as an individual part a cooling
element 60 that corresponds to the cooling elements 5, 11, 21, 22,
35 mentioned above. Just like the evaporator mentioned above, the
cooling element 60 is also composed of aluminum materials and can
thus be soldered to the evaporator. The cooling element 60 is
formed as a rectangular tube 61 in which a holder frame 62 is
inserted that closes the tube 61 on the end. The two connection
ports 60a, 60b are arranged on the narrow side of the rectangular
tube 60. FIG. 5a shows the interior of the rectangular tube 60,
wherein an angled separating wall 63 is arranged between the
coolant inlet 60a and the coolant outlet 60b. Thus there is an
approximately U-shaped flow channel between the two connection
ports 60a, 60b, i.e., the cooling element 60 carries a double flow.
Flow arrows E for the inflow of the coolant and U for the reversal
of the coolant are shown in FIG. 5c. The U-shaped flow channel is
filled with a turbulence plate 64, which is shown in cross section
in FIG. 5c. It can be soldered to the rectangular tube 60. There
are free spaces 65, 66, i.e., not occupied by the turbulence plate,
in the region of the inlet and outlet ports 60a, 60b for the
distribution or collection of the coolant. The coolant is
preferably a fluid heat carrier, especially a water-Glysantin
mixture.
[0050] FIGS. 6 and 6a show another embodiment of a cooling element
70 that can carry a single flow. The cooling element 70 is also
constructed as a rectangular tube 71 and has an inlet port 70a on
the narrow side in its bottom region and an outlet port 70b on the
same side in its upper region for connection to the secondary
circuit, not shown here. In FIG. 6a, the interior, i.e., the flow
path of the coolant through the cooling element 70, is shown by
means of an inlet-side flow arrow E and an outlet-side flow arrow
A. Between the inlet and outlet ports 70a, 70b there is a
turbulence plate 72 that leaves spaces 73, 74 free for the
distribution and collection of the coolant within the cooling
element 70. Through the turbulence plate 72, the heat transfer from
the coolant to the rectangular tube and thus also to the
refrigerant is improved. Compared with the embodiment according to
FIGS. 5 to 5c with a double flow, a smaller coolant-side pressure
drop, but also a smaller cooling output is produced for the single
flow. Instead of the turbulence plate 72, other means increasing
the heat transfer are also possible, e.g., simple internal
ribbing.
[0051] FIGS. 7a, 7b, 7c, 7d show additional embodiments for a
cooling element. Identical features are designated with the same
reference symbols as in the preceding figures.
[0052] FIG. 7a corresponds to FIG. 5b.
[0053] FIG. 7b shows another embodiment for a cooling element 90
that can carry a single flow. The cooling element 90 is also
constructed as a rectangular tube and has an inlet port 90a on the
narrow side in its bottom region and an outlet port 90b in its
upper region for connecting to the secondary circuit, not shown
here. The interior, i.e., the flow path of the coolant through the
cooling element 90, is shown by inlet-side flow arrows E and
outlet-side flow arrows A. Between the inlet and outlet ports 90a,
90b there is a turbulence plate 92 that leaves spaces free for the
distribution and collection of the coolant within the cooling
element 90. Through the turbulence plate 92, the heat transfer from
the coolant to the rectangular tube and thus also to the
refrigerant is improved. In comparison with FIG. 5b, the inlet and
outlet ports 90a, 90b are arranged on the opposite side.
[0054] FIG. 7c corresponds to FIG. 6a.
[0055] FIG. 7d shows another embodiment for a cooling element 100
that can carry a single flow. The cooling element 100 is also
constructed as a rectangular tube and has an inlet port 100a on the
narrow side in its lower region and, in contrast to FIG. 6 and FIG.
7c, has an outlet port 100b in its upper region on the opposite
side of the cooling element 100 for connection to the secondary
circuit, not shown here.
[0056] FIGS. 8a, 8b, 8c, 8d, 8e show various possibilities for the
arrangement or integration of cooling elements in an evaporator.
Identical features are designated with the same reference symbols
as in the preceding figures.
[0057] In FIG. 8a, a cooling element 80 is arranged between
adjacent flat tubes 81 of a double-flow flat tube evaporator. The
walls of the cooling element 80 contact the flat tubes 81 directly
and are preferably soldered to these tubes, which produces an
excellent heat transfer. The heat released by the coolant in the
cooling element 80 flows directly into the flat tubes 81 in which
the refrigerant is flowing. Corrugated fins 82, which are also
soldered to the flat tubes 81, are arranged on the sides of the
flat tubes 81 facing away from the cooling element 80.
[0058] FIG. 8b shows another embodiment, two cooling elements 80
that are each arranged between adjacent flat tubes 81. The two
cooling elements 80 release their heat on one side to the middle,
and on the other side to the two outer, flat tubes 81.
[0059] FIG. 8c shows another asymmetric arrangement, wherein the
cooling element 80 contacts on one side, i.e., with one broad side,
the flat tubes 81 and on the other side, i.e., with the other broad
side, corrugated fins 82. All of the parts are soldered to each
other, so that the heat is released from the cooling element 80 on
one side into the flat tubes 81 and on the other side via the
corrugated fins 82 to the air flowing above, shown by arrows L.
[0060] FIG. 8d shows another embodiment, wherein the cooling
element 80 is arranged directly between adjacent corrugated fins 82
that are in heat-conductive contact with flat tubes 81 on the other
side. The heat generated by the cooling element 80 flows via heat
conduction directly into the corrugated fins 82 and is released on
both sides to the surrounding air flowing over the corrugated fins
82.
[0061] FIG. 8e shows another embodiment. The flat tube evaporator
has at least one flat tube 81, especially several flat tubes 81, as
well as at least one outer flat tube 83, especially two outer flat
tubes. The outer flat tube 83 has a first inner side 84, which is
arranged adjacent to a corrugated fin 82, or in another, not-shown
embodiment adjacent to a flat tube 81. Next to the first inner side
84, the outer flat tube 83 has an essentially parallel second outer
side 85. The second outer side 85 of the outer flat tube 83 is
connected with a material fit to the cooling element 80, especially
through soldering, welding, adhesion, etc., whereby an excellent
heat transfer is produced. The heat released from the coolant in
the cooling element 80 flows directly into the outer flat tube 83
in which the refrigerant flows. Especially advantageous is to
replace at least one side part, which delimits, in particular, the
tube block to the outside, by the cooling element 80. In
particular, two side parts, which each delimit the tube block to
the outside, are replaced by two cooling elements. In this way, at
least one side part is eliminated and the costs are reduced.
[0062] In another embodiment that is not shown, the second outer
side 85 of the outer flat tube 83 is connected to the cooling
element 80 with a positive fit, especially with a clip connection,
screw connection, etc., or with a positive and material fit. In the
shown construction, a cooling element 80 is connected to at least
one second outer side 85 of an outer flat tube 83.
[0063] In another embodiment, the flat tube evaporator has two
outer flat tubes 83, one on each outer side. Each cooling element
80 is connected to an outer flat tube 83, especially with a
material fit through soldering, welding, adhesion, etc., so that
the flat tube evaporator has a total of two cooling elements
80.
[0064] In another not-shown embodiment, the flat tube evaporator
has more than two cooling elements. One cooling element 80 is
connected to an outer flat tube, at least one other cooling element
80, especially several other cooling elements 80, [these] are
arranged between two flat tubes 81 in a first variant or between
two corrugated fins 82 in a second variant or between a flat tube
and a corrugated fin in a third variant, and connected to these
parts or arranged as a combination of the three variants.
[0065] FIG. 9a shows the front view of a flat tube evaporator with
cooling elements arranged on the evaporator block on the outside.
FIG. 9b shows the associated isometric representation of a flat
tube evaporator with cooling elements arranged on the evaporator
block on the outside. FIG. 9c shows the associated cooling element.
Identical features are provided with the same reference symbols as
in the preceding figures.
[0066] FIGS. 9a, 9b show a flat tube evaporator 270, which is
connected on the refrigerant side to a refrigerant circuit 300 of a
not-shown motor vehicle air-conditioning system. In the refrigerant
circuit, a condenser 280 and a compressor 290 are arranged next to
the evaporator 270. The evaporator 270 corresponds in its
construction essentially to the state of the art (DE 198 26 881 A1
by the applicant) mentioned above and carries a flow of a
conventional refrigerant (R134a). In addition, in another
construction it is operated with an alternative refrigerant
CO.sub.2 or R744. The evaporator 270 thus has flat tubes 230 and
outer flat tubes 220 on undesignated corrugated fins, as well as
upper and lower collecting tanks 230 and 320. A block 370 has the
flat tube 230, two outer flat tubes 220, and also undesignated
corrugated fins. The block 370 is delimited on two opposing sides
by a cooling element 210. At least one cooling element 210, in
particular each cooling element 210, is connected to a secondary
circuit 380. The secondary circuit 380 has at least one feed line
350 and at least one return line 360. The secondary circuit has at
least one load with at least one cooling body 330, which is
heat-conductively connected to at least one electronic component
340 to be cooled. The return line 360 is arranged upstream of the
cooling body 330 and is connected to at least one outlet connection
260 of the cooling element 210. The feed line is arranged
downstream of the cooling body 330 and is connected to at least one
inlet connection 250 of the cooling element 210. The cooling
element 210, secondary circuit 380, and cooling body 330 carry a
coolant, preferably a fluid coolant, especially a water-Glysantin
mixture, wherein the coolant can be circulated by a not-shown pump.
Other not-shown loads can be arranged, which are likewise cooled by
the coolant flow, in the secondary circuit 380, which thus acts as
a cooling circuit. The one or more cooling elements 210 transfer
the heat absorbed by the coolant to the one or more outer flat
tubes 220 and thus to the evaporator 270 and the refrigerant, i.e.,
the evaporator 270 acts as a heat sink for the cooling circuit 380.
The one or more cooling elements 210 are arranged adjacent and
especially parallel to the outer flat tube 220 of the evaporator
270, and in particular are connected to the outer side of the flat
tube in a conductive, especially a heat-conductive way and with a
material fit, especially through soldering, welding, adhesion,
etc., and/or with a positive fit, especially through clips, screws,
etc. According to the required cooling power, only one cooling
element 210 can be connected to an outer flat tube 220. For a
greater required cooling power, a cooling element is connected to
each of the two outer flat tubes 220, so that at least two cooling
elements 210 are connected to the evaporator 270. In comparison to
the construction in FIGS. 1, 3, 4, the width 390 of the cooling
element can be designed as larger or smaller according to the
required cooling power. In FIGS. 1, 3, 4 the width 390 of the
cooling element must be adapted to the modular dimensions of the
flat tubes or the corrugated fins. In this embodiment, the width
390 of the cooling element 210 can be steplessly variable. With
this embodiment, the number of cooling elements, and the width 390
according to the cooling power required in the secondary circuit
380, can be assembled as in a modular system. The one or more inlet
connections 250 and one or more outlet connections 260 are arranged
essentially parallel to each other, in the embodiment essentially
adjacent to the lower collection tube 320. The cooling element 210
comprises a first outer face 390, a second outer face 400, and also
a third outer face 410. In addition, the cooling element has a
fourth outer face, which has essentially the size of the first
outer face 390 and which is arranged essentially parallel to this
face, a fifth outer face, which has essentially the size of the
second outer face 400 and which is arranged essentially parallel to
this face, and also another sixth outer face, which has essentially
the size of the third outer face 410 and which is arranged
essentially parallel to this face. In another embodiment, the one
or more inlet connections 250 and the one or more outlet
connections are arranged on at least the first outer face 390,
and/or the second outer face 400 and/or the third outer face 410
and/or the fourth outer face and/or the sixth outer face, wherein
the inlet connections 250 and the outlet connections 260 can be
arranged on the same outer face of the same cooling element 210 or
the inlet connections 250 can be arranged on a different outer face
of the same cooling element 210 than the face on which the outlet
connections 260 are arranged. FIG. 9c corresponds to FIG. 7a and
shows a section through the cooling element 210. Identical elements
are here designated with the same reference symbols as in the
preceding figures. The cooling element 210, however, can also be
formed as shown in FIG. 7b, 7c, or 7d.
[0067] FIG. 10a shows the front view of a flat tube evaporator with
cooling elements arranged on the outside on the evaporator block.
FIG. 10b shows the isometric representation of a flat tube
evaporator with cooling elements arranged on the outside on the
evaporator block. FIG. 10c shows the isometric representation of
another embodiment of a flat tube evaporator with cooling elements
arranged on the outside on the evaporator block. FIG. 10d shows a
cooling element that can carry a single flow. Identical features
are provided with the same reference symbols as in the preceding
figures.
[0068] In contrast to FIG. 9a, FIGS. 10a and 10b show a cooling
element 510. The inlet connection 550 is arranged in the lower
region of the cooling element 510, essentially adjacent to the
lower collecting tank 320, and the outlet connection 560 is
arranged in the upper region of the cooling element 510,
essentially adjacent to the upper collecting tank 310. A second
cooling element 520 has an inlet connection 550 in the upper region
of the cooling element 520, essentially adjacent to the upper
collecting tank 310, and an outlet connection 560 in the lower
region of the cooling element 520, essentially adjacent to the
lower collecting tank 320. The secondary cooling circuit 680 has a
feed line 650 and a return line 660. The coolant flows through the
first cooling element 510 and the second cooling element 520 in
series. Here, the coolant of the secondary circuit 680 enters into
the cooling element 510 on the feed side 650 via the inlet
connection 550, flows through this cooling element, and leaves this
cooling element 510 via the outlet connection 560. The coolant then
flows via a not-shown line to the inlet connection 550 of the
second cooling element 520, flows through this cooling element, and
emerges from the second cooling element 520 via the outlet
connection. However, the reverse direction of flow is also
possible.
[0069] FIG. 10c shows another embodiment. Two cooling elements 710
of an evaporator 770 each comprise an inlet connection 750, which
is arranged in the lower region of the cooling element 710
essentially adjacent to the lower collecting tank 320, and an
outlet connection 760, which is arranged in the upper region of the
cooling element 710 essentially adjacent to the upper collecting
tank 310. The secondary cooling circuit 880 has a feed line 850 and
a return line 860. The coolant flows through the first cooling
element 710 and the second cooling element 710 in parallel. Here,
the coolant of the secondary circuit 880 branches at a not-shown
position on the feed side 850 and enters the respective cooling
element 710 via the inlet connection 750, flows through this
cooling element, and leaves the respective cooling element 510
[sic; 710] via the outlet connection 760. The two discharged
coolant flows combine at a not-shown position in the return line
860. However, the reverse direction of flow is also possible.
[0070] FIG. 10d corresponds to FIG. 7c and shows a section through
the cooling elements 510, 520, 710. Identical elements are here
designated with the same reference symbols as in the preceding
figures. The cooling elements 510, 520, 710, however, can also be
formed as shown in FIG. 7a, 7b, or 7d.
[0071] FIG. 11a shows the rear view of a flat tube evaporator with
cooling elements arranged on the outside on the evaporator block.
FIG. 11b shows an isometric representation of a flat tube
evaporator with cooling elements arranged on the outside on the
evaporator block. FIG. 11c shows a cooling element that can carry a
single flow. Identical features are provided with the same
reference symbols as in the preceding figures.
[0072] In contrast to the preceding figures, the cooling element
910 has an inlet connection 950 and an outlet connection 960 on the
rear side instead of on the front side. FIG. 11c corresponds to
FIG. 10d and shows the cooling element 910.
[0073] Other configurations are conceivable, for example, an
arrangement of the cooling elements on the collecting tanks.
[0074] A cooling device is contemplated as another embodiment of
the invention consisting of an evaporator that is arranged in a
refrigerant circuit of a not-shown motor vehicle, a secondary
circuit, and also a radiator that is arranged in the cooling
circuit of a not-shown internal combustion engine of the motor
vehicle. Evaporator, refrigerant circuit, and secondary circuit
correspond to the embodiment according to FIG. 1 and the subsequent
figures. The secondary circuit is used--as described above--for
cooling loads generating heat, especially not-shown electronic
components, wherein the evaporator is used with at least one
cooling element, not shown here, as a heat sink. The secondary
circuit has a feed line and a return line and is connected via
connection lines to the radiator such that this is connected
parallel to the not-shown cooling element arranged on the
evaporator. The cooling circuit of the internal combustion engine
(engine cooling circuit) and the secondary circuit both have the
same coolant. The radiator is connected alternatively, i.e.,
instead of the cooling element, in the event that the
air-conditioning system in the motor vehicle fails, and thus the
evaporator is not functional. Activation is realized via not-shown
thermostatically or electrically controllable valves in the feed
line or return line. The radiator, which is also part of the
not-shown air-conditioning system, is impinged upon by air on the
secondary side, so that cooling of the coolant and thus of the
secondary circuit can be realized. The radiator is thus used as an
alternative to the evaporator as a heat sink for the secondary
circuit. Advantageously, there can be a short-circuit line between
the feed line and return line that can be controlled via a
not-shown thermostatic valve and that adjusts the temperature of
the return line for the purpose of preventing condensation at a
certain temperature.
[0075] Also contemplated as another embodiment of the invention, a
cooling device has an evaporator and an additional heat exchanger
arranged behind the evaporator in the direction of air flow. The
evaporator is part of a not-shown motor vehicle air-conditioning
system and is connected to a refrigerant circuit. The construction
of the evaporator corresponds to the state of the art--here a flat
tube evaporator whose flat tubes, not shown, carry a flow of
refrigerant of the refrigerant circuit, while a flow of air passes
through the similarly not-shown fins between the flat tubes. The
air is thus cooled in the evaporator and encounters the additional
heat exchanger, which is preferably formed as a serpentine heat
exchanger with a flat tube having multiple reversals, after
emerging from the evaporator. The serpentine heat exchanger has two
connections by means of which it is connected to a secondary
circuit that corresponds to the secondary circuits described above
and which is used for cooling loads generating heat, especially
electronic components in the motor vehicle. The additional heat
exchanger is cooled by the air cooled in the evaporator and is thus
used as a heat sink for the secondary circuit, wherein the
evaporator acts indirectly as a heat sink--via the air.
Advantageously, the additional heat exchanger, which has a
relatively small depth in the direction of the air flow, is
arranged between the evaporator and a heating body that is
connected to the cooling circuit of the internal combustion engine.
The end face of the additional heat exchanger can correspond
approximately to the end face of the evaporator. The volume flow of
the coolant in the additional heat exchanger is relatively
small--in this respect connecting the individual tubes in
succession, e.g., in the form of the serpentine heat exchanger, is
advantageous. Thus, a relatively strong cooling effect is also
provided. The additional heat exchanger can be connected
mechanically or with a material fit (e.g., through soldering) to
the evaporator or to the heating body and thus can be integrated
into a standard air-conditioning system.
[0076] In particular for the case in which a greater throughput of
coolant through the additional heat exchanger is provided, it can
also prove useful for several tubes to be arranged into groups in
which the coolant flows in a uniform direction. The tubes are then
connected by a suitable distribution or collection device to the
corresponding coolant connection lines, for example, by known
collection tubes. In practice, 2, 3, 4, 5, or 6 blocks has proven
effective. Such a construction especially enables reduction of the
flow resistance of the cooling water.
[0077] Obviously, it is also possible--especially in the case of
high coolant throughputs--for the coolant to flow in the same
direction in all of the tubes of the additional heat exchanger.
[0078] While the preferred embodiment of the invention has been
illustrated and described in the drawings and foregoing
description, the same is to be considered as illustrative and not
restrictive in character, it being understood that all changes and
modifications that come within the spirit of the invention are
desired to be protected.
* * * * *