U.S. patent application number 11/572621 was filed with the patent office on 2008-08-14 for coolant cooler with a gearbox-oil cooler integrated into one of the cooling water reservoirs.
This patent application is currently assigned to BEHR GmbH & KG.. Invention is credited to Eberhard Pantow.
Application Number | 20080190597 11/572621 |
Document ID | / |
Family ID | 34993031 |
Filed Date | 2008-08-14 |
United States Patent
Application |
20080190597 |
Kind Code |
A1 |
Pantow; Eberhard |
August 14, 2008 |
Coolant Cooler With A Gearbox-Oil Cooler Integrated Into One Of The
Cooling Water Reservoirs
Abstract
The invention relates to a coolant cooler (7, 107) with a
gearbox oil cooler (5, 105) which is integrated into one of the
cooling water reservoirs (6, 106) of the coolant cooler (7, 107),
wherein a second coolant inlet (13) and/or a second coolant angle
(20) is/are provided on the coolant water reservoir (6, 106),
enabling the circulation of coolant even when the motor thermostat
(11) is closed.
Inventors: |
Pantow; Eberhard;
(Moglingen, DE) |
Correspondence
Address: |
FOLEY AND LARDNER LLP;SUITE 500
3000 K STREET NW
WASHINGTON
DC
20007
US
|
Assignee: |
BEHR GmbH & KG.
|
Family ID: |
34993031 |
Appl. No.: |
11/572621 |
Filed: |
July 1, 2005 |
PCT Filed: |
July 1, 2005 |
PCT NO: |
PCT/EP2005/007096 |
371 Date: |
January 24, 2008 |
Current U.S.
Class: |
165/287 ;
165/164; 165/173 |
Current CPC
Class: |
F01P 7/165 20130101;
F01P 2007/146 20130101; F01P 2060/045 20130101; F28F 9/0234
20130101; F01P 2070/04 20130101 |
Class at
Publication: |
165/287 ;
165/164; 165/173 |
International
Class: |
F01P 7/16 20060101
F01P007/16; F28F 9/02 20060101 F28F009/02 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 26, 2004 |
DE |
10 2004 036 185.1 |
Claims
1. A heat exchanger, in particular coolant cooler with an
additional heat exchanger, in particular transmission oil cooler,
integrated into one of the collecting or water reservoirs of the
heat exchanger or coolant cooler wherein a second coolant inlet
and/or a second coolant outlet is/are provided on the collecting or
water reservoir.
2. The coolant cooler as claimed in claim 1, wherein the second
coolant inlet and/or the second coolant outlet can be closed in a
controlled manner by a thermostat.
3. The coolant cooler as claimed in claim 1, wherein the second
coolant inlet and/or the second coolant outlet is/are connected to
a bypass line which branches off from an engine thermostat or leads
to an engine thermostat.
4. The coolant cooler as claimed in claim 1, wherein the second
coolant inlet and/or the second coolant outlet is/are arranged in
the outlet water reservoir.
5. The coolant cooler as claimed in claim 1, wherein the second
coolant inlet and/or the second coolant outlet is/are arranged
above the transmission oil cooler.
6. The coolant cooler as claimed in claim 2, wherein the thermostat
has an expansion element which projects into the water
reservoir.
7. The coolant cooler as claimed in claim 1, wherein a flow divider
is arranged in the water reservoir the flow divider separating a
sensor region of the thermostat in a region essentially free from
coolant flow from the inflow region of the second coolant
inlet.
8. The coolant cooler as claimed in claim 1, wherein the second
coolant inlet and/or the second coolant outlet can be closed in a
controlled manner by an, in particular, electronically controllable
valve.
9. The coolant cooler as claimed in claim 8, wherein the valve is a
thermostat, in particular with an expansion element, which, in
particular, has a heating system for controlling the
thermostat.
10. A method for controlling a coolant cooler as claimed in claim
1, wherein the second coolant inlet and/or the second coolant
outlet is/are controlled by a thermostat as a function of the
coolant temperature.
11. The method as claimed in claim 10, wherein the second coolant
inlet and/or the second coolant outlet is/are opened when the
engine is not yet at its operating temperature and the transmission
oil is too hot.
12. The method as claimed in claim 1, wherein the second coolant
inlet and/or the second coolant outlet is/are opened when the
engine is, in particular, not yet at its operating temperature and
the transmission oil is not yet at its operating temperature.
13. The method as claimed in claim 1, wherein opening the second
coolant inlet and/or the second coolant outlet is predetermined
from the outside, in particular by heating a thermostat closing the
opening.
Description
[0001] The invention relates to a coolant cooler with a
transmission oil cooler, which is integrated into one of the water
reservoirs, for cooling transmission oil, according to the
precharacterizing clause of claim 1.
[0002] FIG. 6 illustrates, according to the prior art, a coolant
circuit 201 for cooling a refrigerant flowing through the engine
203, and a transmission oil circuit 202 for cooling a transmission
oil flowing through a transmission 204. In this case, the
transmission oil, owing to the increased heat input, is cooled by
the colder coolant in the transmission oil cooler 205, which is
arranged in a water reservoir 206 of the coolant cooler 207, the
cooling power of the transmission oil cooler 205 being coupled to
the flow through the coolant cooler 207. The flow directions of
coolant and transmission oil are indicated by arrows. In the
present case, an engine thermostat 211 is arranged on the coolant
outlet side of the engine 203 and makes it possible, when the
engine 203 is cold, for the coolant, by passing the coolant cooler
207, to pass directly via a bypass 213 to the pump 212 and back
into the engine 203, i.e. coolant does not flow in the coolant
cooler 207.
[0003] In the case of an arrangement of this type, during normal
operation the transmission oil usually reaches transmission oil
temperatures which are below the maximum value for continuous
operation. At low coolant temperatures, which are below the opening
temperature of the thermostat of the engine, the flow generally
does not pass through the coolant cooler, and therefore cooling of
the transmission is prevented. If there is a small leakage from the
thermostat or at the beginning of the opening of the thermostat,
the coolant passes through the coolant cooler at such a low rate
that there is only a small cooling power available in the water
reservoir for the transmission oil cooler, with the result that
again excessive cooling of the transmission is prevented.
[0004] However, operating states may occur, in which the
transmission generates very high amounts of waste heat, but the
engine is not yet at its operating temperature, and so adequate
cooling of the transmission oil cannot be ensured and there is the
risk of the transmission overheating. This risk can be reduced by a
fundamental leakage from the thermostat, but because of the
associated, continuous heat output from the refrigerant cooler, the
heating of the engine is delayed, and so the fuel consumption and
pollutant emissions are increased and the heating comfort leaves
something to be desired.
[0005] It is the object of the invention to provide an improved
coolant cooler with a transmission oil cooler integrated into one
of the water reservoirs, in accordance with which sufficient
cooling of the transmission oil can be ensured even when the engine
thermostat is closed. The coolant cooler is to be as cost-effective
as possible.
[0006] This object is achieved by a heat exchanger with an
additional heat exchanger, which is integrated in one of the
collecting reservoirs, having the features of claim 1. Advantageous
refinements are the subject matter of the subclaims.
[0007] The invention relates in particular to a coolant cooler with
a transmission oil cooler integrated into one of the water
reservoirs of the coolant cooler, wherein a second coolant inlet
and/or a second coolant outlet is/are provided on the water
reservoir, enabling the circulation of coolant even when the engine
thermostat is closed, in particular when the engine is cold but the
transmission oil is too hot. In this case, the transmission oil
circuit preferably entirely corresponds to a conventional
transmission oil circuit, and so no changes are required in this
region, and the old components can continue to be used. Only on the
water reservoir does a second coolant inlet and/or a second coolant
outlet have to be provided, with the control preferably taking
place via a thermostat, which can be integrated into the water
reservoir or can be integrated in the coolant inlet or outlet.
Apart from a bypass line to the second coolant inlet or outlet and
a further branch line in the conventional coolant circuit, no
changes are required, and it is possible for the branch line also
to be integrated directly into the engine thermostat.
[0008] The second coolant inlet and/or the second coolant outlet
is/are preferably arranged in the outlet water reservoir, in which
the coolant temperature is below that of the coolant which comes
from the engine and flows into the inlet water reservoir, thus
making more effective cooling of the transmission oil possible
because of the lower temperature. The inlet and/or outlet is/are
preferably situated above the transmission oil cooler, since, in
this upper region, when the flow is not passing through the coolant
cooler, which is the case in particular when the engine is cold,
the coolant temperature is higher than in the lower region of the
water reservoir, since the hot coolant rises upward.
[0009] The thermostat preferably has an expansion element which
projects into the water reservoir. With the aid of the expansion
element, which expands at high temperatures and, in accordance with
the arrangement of the same, opens a valve, the inlet or outlet can
be controlled cost-effectively and in a simple manner.
[0010] In this case, in particular for inflowing coolant, a flow
divider is arranged in the water reservoir, the flow divider
separating a sensor region of the thermostat, that is, for example,
the region in which an expansion element is arranged, in a region
essentially free from coolant flow from the inflow region of the
second coolant inlet.
[0011] Control of the flow through the water reservoir, in which
the transmission oil cooler is arranged, as a function of the
coolant temperature ensures that the transmission oil is adequately
cooled and prevents overheating of the transmission oil, which,
without appropriate control, could take place, in particular if the
engine is not yet at its operating temperature and the transmission
oil is too hot. The entire arrangement here is only insignificantly
more expensive than a conventional arrangement with coolant circuit
and transmission oil circuit.
[0012] According to a preferred embodiment, a valve closing the
second coolant inlet and/or the second coolant outlet, in
particular the thermostat, is activated from the outside, for
example via electronics, and particularly preferably by heating.
This makes it possible to actively heat the transmission oil in
order, at low loads, to bring it more rapidly to the operating
temperature and therefore to reduce friction losses. An opening of
the valve at a coolant temperature somewhat below the temperature
at which the engine thermostat opens is particularly
advantageous.
[0013] This enables the transmission oil to be heated before the
coolant cooler outputs heat to the surroundings.
[0014] The invention is explained in detail below using two
exemplary embodiments and with reference to the drawing, in
which:
[0015] FIG. 1 shows a schematic illustration of a coolant circuit
and of a transmission oil circuit according to the first exemplary
embodiment,
[0016] FIG. 2 shows a schematic side view of the outlet water
reservoir with transmission oil cooler according to the first
exemplary embodiment,
[0017] FIG. 3 shows a schematic detail illustration of the upper
region of the outlet water reservoir of FIG. 2,
[0018] FIG. 4 shows a schematic illustration of a coolant circuit
and of a transmission oil circuit according to the second exemplary
embodiment,
[0019] FIG. 5 shows a schematic detail illustration of the upper
region of the outlet water reservoir according to the second
exemplary embodiment, and
[0020] FIG. 6 shows a schematic illustration of a coolant circuit
and of a transmission oil circuit according to the prior art.
[0021] FIG. 1 shows a coolant circuit 1 and a transmission oil
circuit 2 of a transmission 4, which is connected to an engine 3
and has an infinitely variable transmission ratio, according to the
first exemplary embodiment. In this case--in accordance with the
prior art--in order to cool the transmission oil a transmission oil
cooler 5 is arranged in a water reservoir 6, in the present case
the outlet water reservoir 6', of a coolant cooler 7. The
transmission oil circuit 2 corresponds here to the transmission oil
circuit 102 according to the previously described prior art, and so
it is not discussed in more detail.
[0022] During normal operation--in accordance with conventional
coolant circuits--the coolant coming from the engine 3 flows via a
line 8 to the coolant cooler 7, which it leaves at the coolant
outlet connection piece 9, and via a line 10 to an engine
thermostat 11 and via a coolant pump 12 back to the engine 3. If
the coolant is adequately cool, for example during starting of the
engine 3, then the engine thermostat 11 blocks the line 10, and the
coolant passes via a bypass 13 directly from the engine 3 to the
engine thermostat 11 and the pump 12 arranged downstream thereof.
To this extent, the coolant circuit 1 corresponds to a conventional
coolant circuit.
[0023] In addition, in order to ensure adequate cooling of the
transmission oil when the engine thermostat 11 is closed with
regard to the line 10, a second coolant outlet 20 is provided on
the outlet water reservoir 6' of the coolant cooler 7, in which
reservoir the transmission oil cooler 5 is arranged, said second
coolant outlet being controlled by a second thermostat 21, and from
which the coolant can be supplied via a bypass line 22 directly to
the bypass 13. In this case, the thermostat 21 determines the
temperature of the coolant, which is convectively heated in the
water reservoir 6 by the hot transmission oil flowing through the
transmission oil cooler 5. In the present case, the thermostat 21
is mounted directly on the water reservoir 6, but it may also be
integrated into a second coolant outlet connection piece. Since the
hot coolant rises upward in the water reservoir 6, the second
thermostat 21 is provided at the top, above the transmission oil
cooler 5.
[0024] In order for a flow to form through the bypass line 22, a
sufficient drop of pressure is required. When the engine
temperature is controlled via an engine thermostat 11 at the inlet
of the engine, as illustrated in FIG. 1, the heated coolant passes
the engine thermostat 11 via the bypass 13, with the result that
there is a sufficient drop of pressure even when the engine
thermostat 11 is closed, and flow is therefore possible.
[0025] According to a variant which is not illustrated in the
drawing, the bypass line 22 leads to an additional connection piece
directly into the housing of the engine thermostat, the connection
piece being arranged in such a manner that it opens into the engine
return behind the actual valve.
[0026] At low coolant temperatures, it can therefore be ensured
that--when the coolant is at a relatively high temperature in the
region of the transmission oil cooler 5--the operation of the
transmission oil cooler 5 can be guaranteed by adequate flow
passing through the outlet water reservoir 6'.
[0027] In the present case, a thermostat with an expansion element
23 is used as the second thermostat 21, the expansion element 23
projecting into the water reservoir 6. Heating the expansion
element 23 causes the thermostat valve 24, of which the valve seat
25 and valve disk 26 are indicated in FIG. 3, to open up the flow
path through the second outlet connection piece 27 via the bypass
line 22. The convection is indicated in FIG. 3 by an arrow (not
filled in) above the transmission oil cooler 5.
[0028] In the following text, the second exemplary embodiment is
explained in more detail with reference to FIGS. 4 and 5. In this
case, identical elements or elements acting to like effect are
referred to by reference numbers higher by 100 than in the first
exemplary embodiment.
[0029] In this case, a coolant circuit 101 and a transmission oil
circuit 102 are again provided, with the transmission oil circuit
102 corresponding here to the transmission oil circuit 2 and to the
transmission oil circuit 202 according to the previously described
exemplary embodiment and the prior art, and so it is not discussed
in more detail.
[0030] A transmission 104 connected to an engine 103, in the
present case an automatic transmission with a converter clutch, is
cooled by the transmission oil, which flows through the
transmission oil circuit 102 and, in a transmission oil cooler 105,
which is arranged in a water reservoir 106, in the present case
again the outlet water reservoir 106', of a coolant cooler 107,
outputs the absorbed heat to the coolant which circulates in the
coolant circuit 101.
[0031] In contrast to the first exemplary embodiment, the engine
thermostat 111 is arranged in the coolant circuit 101 on the engine
outlet side. During normal operation, the coolant coming from the
engine 103 flows through the engine thermostat 111 via a line 108
to the coolant cooler 107, which it leaves at a coolant outlet
connection piece 109, and via a line 110 to a coolant pump 112 and
back to the engine 103.
[0032] If the coolant is sufficiently cool, for example during
starting of the engine 103, then the engine thermostat 111 blocks
the line 108, and the coolant passes via a bypass 113 from the
engine 103 directly to the line 110 and to the pump 112. To this
extent, the coolant circuit 1 again corresponds to a conventional
coolant circuit, in the present case to the coolant circuit 201
(illustrated in FIG. 6) according to the prior art.
[0033] In addition, in order to ensure adequate cooling of the
transmission oil when the engine thermostat 111 is closed with
respect to the line 108, instead of the second coolant outlet 20
according to the first exemplary embodiment, a second coolant inlet
130 is provided on the outlet water reservoir 106' of the coolant
cooler 107, in which reservoir the transmission oil cooler 105 is
arranged, which second coolant inlet is controlled by a second
thermostat 131. In this case, if the need arises, coolant can pass
via a bypass line 132 from the engine thermostat 111 to the second
thermostat 131 and into the water reservoir 106. From the water
reservoir 106, the coolant, after it has absorbed heat from the
transmission oil cooler 105, passes in a customary manner via the
coolant outlet connection piece 109 and via the line 110 to the
pump 112 and back into the engine 103. In the present case, the
bypass line 132 is integrated into the housing of the engine
thermostat 111 in such a manner that it is closed when the engine
thermostat 111 is open, and so no coolant passes via the bypass
line 132 into the water reservoir 106, but rather all of the
coolant takes the normal flow path via the line 108 to the coolant
cooler 107 and enters the latter via the inlet water reservoir
106'.
[0034] In this case, in accordance with the thermostat 21 of the
first exemplary embodiment, the thermostat 131 determines the
temperature of the coolant, which is convectively heated in the
water reservoir 106 by the hot transmission oil flowing through the
transmission oil cooler 105. The thermostat 131 is fitted directly
in the water reservoir 106 (cf. FIG. 5), but it may also be
integrated into a second coolant inlet connection piece. Since the
hot coolant rises upward in the water reservoir 106, the second
thermostat 131 is fitted, in accordance with the thermostat 21 of
the first exemplary embodiment, at the top, above the transmission
oil cooler 105, but, in the present case, the configuration of the
thermostat 131 differs from that of the thermostat 21.
[0035] The expansion element of the thermostat 131 is arranged here
on a wall of the water reservoir 106, which wall lies opposite the
valve with valve seat and valve disk, with a flow divider in the
form of a partition being arranged in between, so that if the
engine 103 is not at its operating temperature, cool coolant does
not come into contact with the expansion element and thus closes
the thermostat again, although a flow is desired.
[0036] The second thermostat 131 again has an expansion element 133
and a thermostat valve 134 with a valve seat 135 and valve disk
136, which are arranged on a second inlet connection piece 137.
However, the expansion element 133, which is arranged above the
transmission oil cooler 105 on one side of the water reservoir 106
and forms a sensor region of the thermostat 131, and the thermostat
valve 134, which is arranged above the transmission oil cooler 105
on the opposite side of the water reservoir 106, are separated by a
flow divider 138, which is formed by a wall projecting in the
direction of the transmission oil cooler 105, said flow divider
preventing, when the thermostat valve 134 is open, a flow which
cools the expansion element 133 being formed in the region thereof
instead of the flow as a result of the heat convection, and so
unintentional closing of the second thermostat 131 is
prevented.
LIST OF REFERENCE NUMBERS
[0037] 1, 101, 201 Coolant circuit [0038] 2, 102, 202 Transmission
oil circuit [0039] 3, 103, 203 Engine [0040] 4, 104, 204
Transmission [0041] 5, 105, 205 Transmission oil cooler [0042] 6,
106, 206 Water reservoir [0043] 6', 106' Outlet water reservoir
[0044] 6'', 106'' Inlet water reservoir [0045] 7, 107, 207 Coolant
cooler [0046] 8, 108 Line [0047] 9, 109 Coolant outlet connection
piece [0048] 10, 110 Line [0049] 11, 111, 211 Engine thermostat
[0050] 12, 112, 212 Coolant pump [0051] 13, 213 Bypass [0052] 20
Second coolant outlet [0053] 21 Second thermostat [0054] 22 Bypass
line [0055] 23 Expansion element [0056] 24 Thermostat valve [0057]
25 Valve seat [0058] 26 Valve disk [0059] 27 Second outlet
connection piece [0060] 130 Second coolant inlet [0061] 131 Second
thermostat [0062] 132 Bypass line [0063] 133 Expansion element
[0064] 134 Thermostat valve [0065] 135 Valve seat [0066] 136 Valve
disk [0067] 137 Second inlet connection piece [0068] 138 Flow
divider
* * * * *