Integrated heat exchanger

An integrated heat exchanger includes a first heat exchange core adapted for cooling a first heat exchange fluid and a second heat exchange core adapted for cooling a second heat exchange fluid. A first pair of fluid manifolds supports the first and second heat exchange cores and communicates with the first heat exchange core to allow the first heat exchange fluid to pass between the first pair of fluid manifolds and the first heat exchange core. A second pair of fluid manifolds supports the first and second heat exchange cores and communicates with the second heat exchange core to allow the second heat exchange fluid to pass between the second pair of fluid manifolds and the second heat exchange core. The first and second pairs of fluid manifolds form a quadrilateral support structure with each fluid manifold forming a side of the support structure. The fluid manifolds of the first pair of fluid manifolds are positioned on opposite sides of the support structure and are each connected between the second pair of fluid manifolds. Preferably, the first heat exchange core is a coolant radiator core adapted to use a liquid as the first heat exchange fluid and the second heat exchange core is a charge air cooler core adapted to use compressed gas as the second heat exchange fluid. The coolant radiator core has a perimeter that defines a front face of the coolant radiator core, the charge air cooler core is positioned in front of the coolant radiator core, and the second pair of fluid manifolds is positioned outside of the perimeter of the coolant radiator core.

TECHNICAL FIELD 
The present invention relates to cooling systems for internal combustion 
engines and, more particularly, to an integrated heat exchanger 
incorporating at least two heat exchangers into one structure. 
BACKGROUND OF THE INVENTION 
The supercharging of internal combustion engines consists of increasing the 
inlet pressure to the engine cylinders so as to obtain an improved charge 
to the cylinders and hence a higher effective pressure, resulting in an 
increase of power for the same speed. While supercharging advantageously 
improves air pressure in the cylinders, it disadvantageously increases the 
air temperature in the cylinders. 
In a supercharged internal combustion engine, a charge air cooler is 
advantageously arranged downstream of the supercharger, such as a 
turbocharger, to decrease the temperature of air introduced into the 
engine from the turbocharger. The decreased air temperature decreases the 
occurrence of knocking, even when a high compression ratio is employed. 
Furthermore, the air density is increased and thus the volumetric 
efficiency is increased. Due to the high compression ratio and high 
volumetric efficiency, an increased engine power is obtained, which is the 
intrinsic object of employing a supercharged system. 
In addition to a charge air cooler, a supercharged internal combustion 
engine includes a conventional coolant radiator that prevents the engine 
from overheating. The coolant radiator and the charge air cooler operate 
similarly, the main difference being that the coolant radiator employs a 
liquid coolant as a heat exchange fluid while the charge air cooler 
employs compressed gas as the heat exchange fluid. Typically the radiator 
and charge air cooler have manifolds or tanks on opposite sides of a heat 
exchange core. These manifolds direct the heat exchange fluid into cooling 
tubes in the heat exchange core. Air flows between the cooling tubes to 
cool the heat exchange fluid when the vehicle moves in a forward direction 
or when a fan is turned on. 
Shown in FIG. 1 is a conventional design of a coolant radiator/charge air 
cooler system I 0. The system includes a charge air cooler 12 having a 
cooler core 14 connected between a pair of cooler manifolds 16. Likewise, 
a coolant radiator 18 includes a radiator core 20 connected between a pair 
of radiator side tanks 22. 
When the vehicle travels forward, or when a fan (not shown) is turned on, 
air passes through the charge air cooler core 14 and the radiator core 20 
to cool the heat exchange fluids in the cores. However, the charge air 
cooler 12 typically is positioned in front of the coolant radiator 18 and 
is typically smaller than the coolant radiator so that the cooler 
manifolds 16 block a portion of the radiator core 20, thereby decreasing 
the flow of cooling air through the radiator core. By blocking some of the 
air through the radiator core the charge air cooler prevents the coolant 
radiator from operating at optimum efficiency. 
The charge air cooler and coolant radiator are supported by a support 
structure 24. The support structure includes top and bottom horizontal 
support channels 26 connected between left and right vertical side tanks 
22. The support structure also includes structural cross members 30 
extending between opposite corners of the support structure. The charge 
air cooler 12 is attached to the support structure via side brackets 32. 
In addition to adding undesirable weight to the system, a portion of 
support structure blocks a portion of the radiator core, thereby further 
decreasing coolant radiator efficiency. 
SUMMARY OF THE INVENTION 
The present invention is directed to an integrated heat exchanger that 
overcomes the disadvantages of the prior art by providing structural 
efficiency as well as cooling efficiency. In a preferred embodiment, the 
integrated heat exchanger includes a first heat exchange core adapted for 
cooling a first heat exchange fluid and a second heat exchange core 
adapted for cooling a second heat exchange fluid. A first pair of fluid 
manifolds supports the first and second heat exchange cores and 
communicates with the first heat exchange core to allow the first heat 
exchange fluid to pass between the first pair of fluid manifolds and the 
first heat exchange core. A second pair of fluid manifolds supports the 
first and second heat exchange cores and communicates with the second heat 
exchange core to allow the second heat exchange fluid to pass between the 
second pair of fluid manifolds and the second heat exchange core. The 
first and second pairs of fluid manifolds form a quadrilateral support 
structure with each fluid manifold forming a side of the support 
structure. By forming a support structure with the fluid manifolds the 
integrated heat exchanger is efficiently supported without needing a 
separate support frame. 
In the preferred embodiment, the second heat exchange core is positioned in 
front of the first heat exchange core, but the fluid manifolds are 
positioned outside of the perimeter of a front face of the first heat 
exchange core. By positioning the fluid manifolds outside of the perimeter 
of the first heat exchange core, the manifolds do not to impede the flow 
of air through the first heat exchange core. Preferably, the first heat 
exchange core is a coolant radiator core adapted to use a liquid as the 
first heat exchange fluid and the second heat exchange core is a charge 
air cooler core adapted to use compressed gas as the second heat exchange 
fluid.

DETAILED DESCRIPTION OF THE INVENTION 
As shown in FIG. 2, a preferred embodiment of the present invention 
includes an integrated heat exchanger 34 positioned forwardly of an 
internal combustion engine 36 of a vehicle. The integrated heat exchanger 
34 includes a charge air cooler 38 structurally connected to a coolant 
radiator 40. The charge air cooler includes a cooler core 42 connected 
between a pair of cooler manifolds 44, 45. Likewise, the coolant radiator 
40 includes a radiator core 46 connected between a pair of radiator 
manifolds 48, 49. Both the radiator manifolds and the cooler manifolds are 
positioned outside of the perimeter of a front face of the radiator core 
so that the manifolds do not block the passage of air through the radiator 
core. The cooler manifolds are connected between the radiator manifolds so 
as to form a quadrilateral support structure that allows the integrated 
heat exchanger to be supported without a separate support frame. 
The integrated heat exchanger 34 is positioned on a cross member 50 of a 
vehicle frame 52 which also supports the engine 36. Attached to the engine 
is a turbocharger 54 which compresses gas for use by the engine cylinders 
(not shown) in order to improve engine efficiency. The compressed gas is 
passed into the upper cooler manifold 44 via an air input conduit 56. The 
air passes from the upper cooler manifold through the cooler core 42 to 
the lower cooler manifold 45. When the vehicle travels forward or when a 
radiator fan (not shown) is operating, ambient air passes through the 
cooler core and cools the compressed air in the cooler core. The cooled 
compressed air exits the lower cooler manifold and passes to the engine 
cylinders via an air output conduit 58. 
As is well known, a liquid coolant is circulated through the engine 36 in 
order to prevent the engine from overheating. The liquid coolant passes 
from the engine through an input coolant conduit 60 to a first radiator 
manifold 48. The coolant passes from the first radiator manifold through 
the radiator core 46 to the second radiator manifold 49 opposite the first 
radiator manifold. As with the cooler core 42, ambient air passes through 
the radiator core and cools the coolant in the radiator core. The cooled 
coolant returns to the engine via an output coolant conduit 62. 
Shown in FIG. 3 is a more detailed view of the integrated heat exchanger 34 
of FIG. 2. The coolant radiator 40 includes an inlet port 64 that is 
adapted to functionally connect the interior of the first radiator 
manifold 48 to the interior of the input coolant conduit 60 shown in FIG. 
2 to allow the liquid coolant to flow into the radiator manifold. 
Communicating with the interior of the first radiator manifold are a 
plurality of cooling tubes 66 extending across the radiator core 46. As 
the liquid coolant flows through the cooling tubes, ambient air flows 
through the radiator core along the outside of the cooling tubes, thereby 
cooling the coolant in the cooling tubes. The coolant radiator also 
includes an outlet port 68, which is adapted to functionally connect the 
interior of the second radiator manifold 49 to the interior of the output 
coolant conduit 62 shown in FIG. 2 to allow the cooled liquid coolant to 
flow into the output coolant conduit. A conventional surge tank 69 affixed 
to the integrated heat exchanger communicates with one of the radiator 
manifolds 50, 51 by a conduit (not shown) to release overheated coolant 
and to allow the coolant radiator 40 to be filled with liquid coolant and 
vented. 
The charge air cooler 38 includes an input port 70 that allows compressed 
air from the turbocharger 54 via the air input conduit 56 to enter the 
upper cooler manifold 44. The compressed gas flows from the upper cooler 
manifold 44 through a plurality of cooling tubes 72 extending through the 
cooler core 42 to the lower cooler manifold 45. As the compressed gas 
flows through the cooling tubes, ambient air flows through the cooler core 
along the outside of the cooling tubes, thereby cooling the compressed gas 
in the cooling tubes. The cooled, compressed gas exits the lower cooler 
manifold through an outlet port 74 and passes to the engine 36 via the air 
conduit 58 shown in FIG. 2. 
Shown in FIG. 3 are multiple connectors 76 which rigidly connect the 
radiator manifolds 48, 49 to the cooler manifolds 44, 45 to provide a 
rigid support structure. The cooler manifolds 44, 45 include manifold 
extensions 44a, 45a respectively, which connect to the radiator manifolds 
48, 49 via connectors 76. The connectors 76 can be any well-known 
connectors, such as bolts, rivets, or welds. If additional support is 
desired, the walls of the manifolds can be made thicker or of a stronger 
material without requiring the separate support frame required by the 
prior art. 
Those skilled in the art will appreciate that there are numerous possible 
integrated heat exchanger configurations that utilize the concepts of the 
present invention. In one alternative embodiment the positions of the 
cooler manifolds and radiator manifolds are reversed so that the radiator 
manifolds are positioned above and below the radiator core while the 
cooler manifolds are positioned to the left and right of the cooler core. 
Further, although rectangular coolant radiators and charge air coolers are 
typical, the invention may be employed equally satisfactorily in a system 
using coolant radiators and charge air coolers of any shape. 
Heat exchangers other than the single pass charge air coolers and coolant 
radiators shown in the figures may also be used. In one embodiment, two 
charge air coolers are combined into one integrated heat exchanger in 
order to provide cooling for an engine that employs dual turbochargers. In 
an alternate embodiment using a doublepass charge air cooler, the upper 
cooler manifold and the cooler core are divided into two halves. The 
compressed air flows through a first half of the upper cooler manifold and 
cooler core to the lower cooler manifold. The lower cooler manifold 
directs the compressed air to the second half of the cooler core. The 
compressed air flows through the second half of the cooler core and the 
second half of the upper cooler manifold and exits through an outlet port 
in the second half of the upper cooler manifold. 
Each of the embodiments of the invention provide improved efficiency of the 
integrated heat exchanger by preventing the fluid manifolds from blocking 
the passage of ambient air through the heat exchanging cores. Further, a 
second aspect of the invention provides a strong support structure for the 
integrated heat exchanger using the fluid manifolds. As a result, no 
separate support frame is needed to support the integrated heat exchanger. 
From the foregoing it will be appreciated that, although specific 
embodiments of the invention have been described herein for purposes of 
illustration, various modifications may be made without deviating from the 
spirit and scope of the invention. Accordingly, the invention is not 
limited except as by the appended claims.