EP1532413A1

EP1532413A1 - Heat exchange unit for a motor vehicle and system comprising said unit

Info

Publication number: EP1532413A1
Application number: EP03756512A
Authority: EP
Inventors: Pascal Guerrero; Jean-Louis Laveran; Jérôme GENOIST
Original assignee: Valeo Thermique Moteur SA
Current assignee: Valeo Systemes Thermiques SAS
Priority date: 2002-08-28
Filing date: 2003-07-28
Publication date: 2005-05-25
Also published as: WO2004020927A1; FR2844041B1; US20050269062A1; JP4721705B2; JP2005536711A; US7322399B2; FR2844041A1; AU2003293682A1

Abstract

The invention relates to a heat exchange unit for a motor vehicle comprising a heat engine which is equipped with a high-temperature cooling system and a low-temperature cooling system. The inventive unit comprises at least one row of heat exchange tubes (102), which is connected to at least one inlet manifold chamber (58, 64, 66) and at least one outlet manifold chamber (60, 62, 68), said tubes forming a heat exchange surface. The invention also comprises surface distribution means (110, 42, 44) which can be used to divide the heat exchange surface into a high-temperature heat exchange section and a low-temperature heat exchange section. The unit also preferably comprises a high-temperature fixed section (52), a low-temperature fixed section (54) and an intermediary section that can be fully or partially allocated to said sections (52 and 54).

Description

Heat exchange module for a motor vehicle and system comprising this module

The invention relates to the field of heat exchangers, in particular for motor vehicles, whether they are heat exchangers constituted by a single row of tubes or by several rows of superimposed tubes traversed by the same flow of air. These tubes can be straight tubes or even U tubes.

More specifically, the invention relates to a heat exchange module for a motor vehicle with a thermal engine equipped with a high temperature cooling circuit, in particular for cooling the engine, and a low temperature cooling circuit for cooling vehicle equipment, this module comprising at least one row of heat exchange tubes connected to at least one inlet manifold and at least one outlet manifold, these tubes forming an exchange surface heat.

Modern motor vehicles include, in addition to the internal combustion engine itself, numerous pieces of equipment which exchange heat with an external medium, either to be cooled or, on the contrary, to be heated. By way of example, mention may be made of the condenser of the air conditioning circuit in the passenger compartment of the vehicle, the charge air cooler or even the radiator for heating the passenger compartment. This is why these vehicles are generally equipped with two circuits, namely a high temperature circuit which is used for cooling the heat engine and equipment with the highest temperature, and a low temperature cooling circuit which is used for cooling equipment with the lowest temperature, such as the air conditioning system condenser in the passenger compartment of the motor vehicle. In known vehicles, the exchange surface of the high temperature radiator and the exchange surface of the low temperature radiator are fixed. The high temperature radiator is used exclusively for cooling the equipment of the high temperature circuit, while the low temperature radiator is used exclusively for cooling and / or heating the equipment of the low temperature circuit. However, under certain engine load conditions, in particular at low load, it is not necessary to cool the heat engine vigorously. This is why the engine coolant circulates through a bypass line which bypasses the high temperature radiator so that the cooling capacity of the latter is not used. There is therefore a loss of cooling capacity.

The object of the invention is precisely to provide a heat exchange module which overcomes this problem by making the best use of the heat exchange surface available for the needs of the high temperature circuit and of the low temperature circuit.

This object is achieved, in accordance with the invention, by the fact that the heat exchange module comprises surface distribution means which make it possible to split, advantageously in a modular manner, the heat exchange surface into a section d a high temperature heat exchange used for cooling the high temperature circuit and a low temperature heat exchange section used for cooling the low temperature circuit.

Thanks to these distribution means, it is possible to vary the distribution of the overall exchange surface of the module according to the needs of the cooling circuits with high temperature and low temperature. It is thus possible to increase the heat exchange surface available for the high temperature circuit by decreasing the cooling surface available for the low temperature circuit. Conversely, the heat exchange area allocated to the high temperature circuit can be reduced, which simultaneously makes it possible to increase that of the low temperature circuit. In particular, when the engine does not need to be cooled vigorously, a greater cooling capacity can be allocated to the circuit at low temperature and this achieves a better level of performance for cooling the equipment of the circuit at low temperature.

The invention can be generalized to the case where the motor vehicle comprises more than two cooling circuits, for example three, the heat exchange module of the invention could then comprise three heat exchange sections and the surface of The module's overall heat exchange could be distributed between these three exchange sections as required.

Furthermore, the fluids which circulate in the high temperature circuit and in the low temperature circuit can be the same fluid at different temperatures or two fluids of different nature.

In a particular advantageous embodiment, the heat exchange module comprises a fixed heat exchange section permanently integrated into the high temperature cooling circuit, a fixed low temperature heat exchange section permanently integrated into the heating circuit. cooling at low temperature and an assignable heat exchange section comprising an inlet manifold and an outlet manifold and which can be allocated in whole or in part either to the fixed heat exchange section at high temperature, either to the exchange section of fixed heat at low temperature.

If the assignable heat exchange section is allocated in full to one of the fixed high temperature or low temperature heat exchange sections, the high temperature heat exchange section, respectively the exchange section heat at low temperature, consists of a permanent fixed part, namely the fixed heat exchange section at high temperature, respectively at low temperature, increased by the attributable heat exchange section.

The attributable heat exchange section can also be divided between the high temperature and low temperature circuits. In this case, the high temperature heat exchange section consists of its fixed part increased by the fraction of the attributable heat exchange section which is allocated to it. Likewise, the low temperature heat exchange section consists of its fixed part increased by the fraction of the attributable heat exchange section which has not been allocated to the high temperature circuit. - - -

In a particular embodiment, the heat exchange module comprises a single row of tubes.

In another particular embodiment, the heat exchange module comprises a first row of tubes and a second row of tubes, the first row belonging to the fixed exchange section of the high temperature circuit, respectively of the low temperature circuit, the second row of tubes being split into a fixed section at high temperature, into a fixed section at low temperature and into an attributable intermediate heat exchange section, the fixed section at high temperature, respectively the fixed section at low temperature, being connected in series to the first row of tubes. In a third particular embodiment, the heat exchange module comprises three rows of tubes, the first row of tubes belonging to the fixed exchange section of the high temperature circuit, the second row of tubes belonging to the exchange section attributable intermediate heat, the third row of tubes belonging to the fixed low-temperature exchange section.

Thus, in this embodiment, the second intermediate row, which will preferably be placed between the first and the third row of tubes, is connected in series, generally entirely, either to the first row of tubes, or to the second row of tubes.

In each case, said distribution means make it possible to control, for example individually and / or by group, the number of tubes assigned to one or the other of the sections at low temperature or at high temperature. In order to have an advantageous degree of modularity, at least three groups of assignable tubes will be provided.

In another embodiment, the heat exchange module comprises a row of U-shaped tubes, each of which is connected on the one hand to the attributable inlet manifold and on the other hand to the attributable outlet manifold.

In a particular embodiment, the surface distribution means are constituted by adjustable partition means of the inlet manifold of the attributable section and by adjustable means of the manifold outlet of the attributable section, these means of partition allowing modular splitting of the assignable inlet manifold into an inlet chamber attributable to the high temperature circuit and an inlet chamber attributable to the low temperature circuit, and the outlet manifold assignable into a output attributable to the circuit at high temperature and an outlet chamber attributable to the low temperature circuit, the distribution of the inlet manifold and the outlet manifold between these chambers being adjustable.

Said partitioning means will advantageously make it possible to control, tube by tube or group of tubes by group of tubes, whether the said tube or tubes are allocated to the low temperature section or to the high temperature section, this over at least part of the height of manifolds.

By varying simultaneously and synchronously the distribution of the attributable inlet manifold and of the attributable outlet manifold between chambers allocated to the high temperature circuit and chambers allocated to the low temperature circuit, the distribution is varied the overall heat exchange surface of the heat exchange module between the high temperature heat exchange section and the low temperature heat exchange section.

In a particular embodiment, the continuously adjustable partition means are constituted by a piston mounted to slide in the attributable inlet manifold and by a piston mounted to slide in the attributable outlet manifold, these pistons being moved by means of actuation.

The actuating means can be constituted, for example, by endless screws driven in rotation by actuators external to the manifolds.

In another embodiment, the partitioning means of the assignable inlet manifold and the assignable outlet manifold are discreetly adjustable. In a particular embodiment, the discrete adjustment means can consist of a series of partitions actuated by actuators distributed over the length of the attributable inlet manifold and over the length of the attributable outlet manifold, each of these partitions being able to split the inlet manifold, respectively the outlet manifold, into two chambers.

Advantageously, the partitions are isolated from the middle of the heat exchange module by sealing membranes and they are actuated by actuators external to the manifolds.

In a third embodiment, the heat exchange module comprises switching means which make it possible to connect the heat exchange section that can be allocated entirely, either to the fixed heat exchange section at high temperature, or to the fixed heat exchange section at low temperature.

In a particular embodiment, the switching means are constituted by passage orifices provided between the manifolds of the fixed sections at high temperature and at low temperature and the manifolds of the attributable intermediate heat exchange section and by valves which allow these passage openings to be opened or closed selectively.

Advantageously, the valves are connected by a rod to a control member. They are preferably located in the manifolds of the attributable intermediate section disposed between the high temperature and low temperature sections. Thus, a simple reciprocating movement of the valves makes it possible to alternately close either the communication of the intermediate section with the high temperature section, or o the communication of the intermediate section with the low temperature section. Of course, one could also imagine that the valves are arranged in the manifolds of the high temperature and low temperature sections.

Advantageously, the heat exchange module comprises logic control means, means for distributing the heat exchange surface which receive information on control parameters such as the water temperature of the high temperature circuits and at low temperature, the engine load, the engine speed, the power released by the engine to the water, at least one of these parameters governing the distribution of the heat exchange surface.

These logic means can be controlled electronically, pneumatically, electromagnetically and / or thermostatically.

When the heat exchange module of the invention has two or more rows of tubes, the tubes can be fitted with cooling fins common to all the rows of the module. -

Thus, if the module has two rows of tubes, the cooling fins, whether they are flat fins or corrugated spacers, can be common to the two rows of tubes.

The manifolds of the heat exchange module of the invention may consist of a collecting plate and a cover assembled by brazing, these elements preferably being made of aluminum.

Alternatively, the manifolds of the heat exchange module may consist of a manifold plate and a cover, in particular made of plastic, fixed mechanically on the collector plate.

Furthermore, the invention relates to a thermal energy management system developed by a thermal engine of a motor vehicle, comprising a high temperature cooling circuit comprising a high temperature radiator for cooling in particular the vehicle engine, and a circuit low temperature cooling system comprising a low temperature radiator for cooling equipment of the motor vehicle.

According to the invention, the high temperature radiator is constituted by the high temperature heat exchange section of a heat exchange module according to the present invention and the low temperature radiator is constituted by the section d heat exchange at low temperature of this same module.

Advantageously, the logic means for controlling the means for distributing the heat exchange surface are coupled to management by a four-way valve for cooling the engine, said valve comprising an inlet channel connected to the outlet of the engine, and by three output channels connected respectively to one air heater, to the bypass pipe of the engine and to the heat exchange module according to the invention.

Other characteristics and advantages of the invention will become apparent on reading the following description of embodiments given by way of illustration with reference to the appended figures. In these figures:

- Figure 1 schematically shows a thermal energy management system developed by a thermal engine of a motor vehicle according to the present invention; - Figure 2 is a schematic perspective view of a heat exchange module according to the present invention; - Figure 3 is a schematic perspective view of another heat exchange module according to the present invention, comprising two rows of tubes;

- Figure 4 is a sectional representation of an exemplary embodiment of a heat exchange module with a single row of tubes comprising means for continuously adjusting the distribution of the heat exchange surface;

- Figure 5 is a sectional representation of a heat exchange module according to the invention, comprising means for continuously adjusting the distribution of the heat exchange surface comprising two rows of tubes;

- Figures 6 and 7 are detail views which show discrete partition means of a manifold of a heat exchange module according to the present invention; - Figures 8a to 8e show the successive stages of actuation of discrete partitioning means such as those of Figures 6 and 7;

- Figures 9, 10 and 11 are detailed perspective views which illustrate a first embodiment of discrete partition means;

- Figures 12 and 13 are perspective views which illustrate another embodiment of the discrete partition means;

- Figures 14 to 16 are sectional views which show an embodiment of a heat exchange module according to the invention comprising three rows of tubes and switching means;

- Figure 17 is a perspective view of a heat exchange module with U-shaped tubes comprising means for continuously adjusting the distribution of the heat exchange surface;

- Figure 18 shows the detail D of Figure 17; and

FIGS. 19A to 19F show different positions of the means for adjusting the distribution of the exchange surface of the heat exchange module of FIG. 17.

FIG. 1 shows an overview of a system for managing the thermal energy released by a heat engine, in particular from a motor vehicle, in accordance with the present invention. This system includes a high temperature cooling circuit, designated by general reference 2, and a low temperature cooling circuit designated by general reference 4.

The high temperature circuit comprises an engine inlet pipe 6 connected to the engine 8 of the vehicle and an engine outlet pipe 10 connected to a four-way valve 12. A mechanical or electric pump 14 circulates a cooling fluid coolant through the engine block, as shown by the arrows 15. The high temperature cooling circuit also includes a heating pipe 16 on which is mounted an air heater 18. The circulation pump 14 also makes it possible to circulate the coolant in 1 heater 18, as shown by arrow 19.

From the four-way valve 12, the heat transfer fluid can also pass through a pipe 20 of a high temperature radiator connected to a heat exchange module 22 according to the present invention. The heat exchange module 22 is traversed by the heat transfer fluid, as shown schematically by the. arrows 23. Finally, a bypass pipe or short circuit pipe 24 allows the heat transfer fluid to return to the motor 8 without having passed through the heat exchange module 22, as shown by arrow 25. _. . ..

The four-way valve 12 comprises an inlet channel designated by the reference 12-1 and three outlet channels, respectively a channel 12-2 connected to the radiator pipe 16, a channel 12-3 connected to the radiator pipe at high temperature 20 and a channel 12-4 connected to the short-circuit pipe 24. The secondary cooling circuit 4 comprises a low temperature radiator pipe 28 on which is mounted an electric low temperature circulation pump 30 and one or more heat exchangers 32. In the example shown, a single heat exchanger 32 has been shown. intended for cooling or possibly heating vehicle equipment. The heat exchanger 32 can be, for example, a condenser of an air conditioning circuit or a charge air cooler. It is cooled by heat exchange with the low temperature heat transfer fluid which circulates in the low temperature cooling circuit 4, as shown diagrammatically by the arrow 34. The low temperature fluid is cooled in the heat exchange module 22.

In currently known devices, the high temperature cooling circuit and the low temperature cooling circuit comprise separate cooling exchangers which do not communicate with each other. Consequently, the cooling surface allocated respectively to the high temperature cooling circuit and to the low temperature cooling circuit are fixed. It often happens that the cooling capacity of the high temperature circuit is not used, for example in the event of a low load or a moderate load of the heat engine 8. In this case, the high temperature cooling radiator is bypassed by the pipe. short-circuit 24, so that the cooling capacity of the vehicle is not used to the best.

On the contrary, in accordance with the invention, the heat exchange module 22 comprises means for distributing the overall heat exchange surface of the module 22. These distribution means, designated by the general reference 40, comprise means mechanical 42 controlled by power means 44 able to train them. The power means can be controlled by logic control means 46 which receive information from sensors arranged at appropriate locations in the high temperature cooling circuit and the low temperature cooling circuit. These control parameters can be the water temperature at the outlet of the engine 8 in the line 10, the engine rotation speed, the thermal power rejected by the engine in the high temperature cooling circuit. The logic control means can be controlled by one or more of these parameters combined.

Advantageously, the logic control means 46 are coupled to a management of the four-way valve 12, as shown schematically by the dashed line 48.

The heat exchange module 22, several embodiments of which will be described later, comprises a heat exchange surface made up of parallel heat exchange tubes in which circulates a cooling fluid which exchanges heat with a external environment, for example atmospheric air.

The surface distribution means, and in particular the mechanical means 42, make it possible to modulably split the overall heat exchange surface of the heat exchange module 22 into a high temperature heat exchange section mounted on the high temperature radiator line 20 and traversed by the high temperature coolant, as shown by arrow 23, and a low temperature heat exchange section (not referenced in Figure 1) used for cooling the fluid at low temperature, as shown by arrow 34.

The distribution of the overall cooling capacity of the heat exchange module 22 is controlled as a function of the cooling needs of the high temperature 2 and low temperature 4 circuits. Thus, when the motor 8 operates at low or partial load, these cooling needs are small and most of the high temperature cooling fluid flows through the short-circuit pipe 24. Under these conditions, most, if not all, of the overall exchange surface of the heat exchange module 22 can be recovered for cooling low-temperature equipment shown diagrammatically by the heat exchanger 32. Their performance is thus improved, for example the thermal performance of the air conditioning circuit, by providing a condenser whose cooling capacity is higher.

According to the invention, the mechanical means for distributing the heat exchange surface of the heat exchange module 22 make it possible to distribute this surface in any way. In particular, it is not necessary that the high temperature heat exchange section and the low temperature heat exchange section consist of a single zone of contiguous tubes. On the contrary, they can be distributed in any manner in the heat exchange module 22.

However, in a particular embodiment shown diagrammatically in perspective in FIG. 2, the overall heat exchange surface of the heat exchange module 22 is broken down into three sections, namely a high temperature heat exchange section 52 , a low temperature heat exchange section 54 and an intermediate section 56 disposed between sections 52 and 54. Sections 52 and 54 are fixed. In other words, they are always present and they comprise a determined, fixed number of heat exchange tubes of the heat exchange module 22. The intermediate section 56 can be assigned either to the circuit of high temperature cooling, i.e. to the low temperature cooling circuit. In the first case, the heat exchange surface of the high temperature circuit consists of the sum of the exchange section 52 and the exchange section 56. In the second case, the cooling surface of the circuit to low temperature is made up of the sum of the low temperature heat exchange section 54 and the intermediate section 56.

The intermediate heat exchange section 56 can also be distributed between the sections 52 and 54. One can, for example, allocate three quarters of the intermediate heat exchange section 56 to the low temperature cooling circuit (section 54 ) and the remaining quarter in the high temperature cooling system (section 52). Of course, this proportion can vary, either continuously from 0 to 100%, or by increment, for example by 10% each time.

There is shown in Figure 2 a perspective view of a heat exchange module 22 according to the present invention, schematically consisting of a single row of tubes. It comprises a bundle of parallel, generally flat tubes, designated by the general reference 50. These tubes are preferably in contact with surfaces intended to increase the heat exchange with the external medium, for example flat fins arranged perpendicular to the tubes. , or corrugated spacers arranged between the tubes.

The tubes of the heat exchange module 22 are connected, at each of their two ends, to manifolds, ie namely an inlet manifold for the heat transfer fluid and an outlet box for the outlet of the heat transfer fluid.

In the example shown in Figure 2, the tubes of the high temperature heat exchange section 52 are connected to a high inlet temperature manifold 58 and to a high outlet temperature manifold 60. The tubes of the low temperature heat exchange section 54 are connected respectively to a low temperature inlet manifold 62 and to a low temperature outlet manifold 64. The tubes of the assignable intermediate section 56 are connected, at their inlet end, to an assignable inlet manifold 66 and, at their outlet end, to a attributable manifold 68.

The manifolds 66 and 68 are said to be "attributable" because it is, in fact, via the manifolds 66 and 68 that the intermediate heat exchange surface 56 will be distributed. In practice, to add the intermediate exchange surface 56 to the high temperature heat exchange surface 52, the high temperature inlet manifold 58 and the intermediate inlet manifold 66 are placed in communication, and simultaneously in communication with the high temperature outlet manifold 60 in communication with the intermediate outlet manifold 68.

The procedure is the same with regard to the low temperature cooling circuit 54. And, when it is desired to distribute the intermediate exchange surface 56 between the high temperature and low temperature circuits, one distributes, in the same proportion, the assignable inlet manifold 66 and the assignable outlet manifold 68 between the high temperature and low temperature circuits. - --.-. , - ....

The high temperature heat transfer fluid enters the inlet manifold 58, as shown by the arrow 59, and it emerges from the outlet manifold 60, as shown by the arrow 61, after passing through the exchange section of high temperature heat 52, as shown by the arrow 55. In the same way, the coolant at low temperature enters the low temperature inlet manifold 62, as shown in the arrow 63, and emerges from the low temperature manifold 64, as shown by arrow 65, after having passed through the low temperature exchange section 54, as shown schematically by arrow 57. The intermediate inlet manifold 66 and the intermediate outlet manifold 68 do not have any inlet manifold and clean outlet. The entry of the high temperature heat transfer fluid or the entry of the low temperature heat transfer fluid into the manifolds 66 and 68 is done indirectly, via the inlet and outlet boxes 58, 60, 62, 64 of the high temperature and low temperature circuits.

There is shown in Figure 2 a basic embodiment of a heat exchange module according to the present invention comprising a single row of tubes. However, it goes without saying that, in practice, the heat exchange module can be more complex and in particular comprise several rows of tubes, for example two. It is a module of this type which has been represented in Figure 3.

There is shown in Figure 3 a heat exchange module according to the invention 22, identical in principle to the heat exchange module of Figure 2, but having two rows of tubes instead of one. It consists of a first row of tubes 72 comprising manifolds at each of their two ends and a second row of tubes 74 comprising manifolds at each of their two ends. In other words, the heat exchange module

22 consists of two heat exchangers arranged side by side so that they pass through the same air flow. These two exchangers can be separate and assembled with one another. Or they may include cooling fins common to the two rows of tubes. In this embodiment, the second row of tubes 74 is broken down into three parts, namely a part 52 at high temperature, a part 54b at low temperature and an attributable intermediate part 56. Likewise, the manifolds d the inlet and outlet are divided into three parts, namely respectively an inlet manifold 58 at high temperature, an outlet manifold at high temperature 60, an inlet manifold at low temperature 62, an outlet manifold of low temperature outlet 64, an intermediate inlet manifold 66 and an intermediate outlet manifold 68.

The constitution of the second row of tubes 74 is therefore identical to the constitution of the heat exchange module shown in Figure 2. However, in this embodiment, the first row of tubes 72 is added to the heat exchange section at low temperature 54b of the second row of tubes 74. The coolant at low temperature enters the inlet chamber 62 limited by the partition 78, as shown by the arrow 63. It is distributed in this room, as shown by arrow 80, and it traverses the first pass of the tubes 72 in the direction from left to right, according to Figure 3, to reach the manifold 82 of the first row of tubes. It is distributed in this manifold, as shown schematically by the arrow 84, and enters the lower pass to circulate from right to left, according to Figure 3, and reach the chamber 86 limited by the partition 78. From the chamber 86, the low temperature fluid enters the inlet manifold 62 which is part of the second row of tubes 74, as shown schematically by the arrows 88 and 90, through the opening 92. The ambient air crosses the row 72 then row 74. The low temperature fluid leaves the module according to arrow 65.

Thus, in this exemplary embodiment, the fixed heat exchange section at low temperature, permanently assigned to the low temperature circuit, consists of two distinct parts, namely on the one hand all the tubes of the first row 72 and a fraction of the tubes of the second row 74. In this way, the heat exchange section at low temperature is much larger than the high temperature heat exchange section. In addition, the attributable intermediate part 56 can be integrated, by the means for distributing the heat exchange surface area according to the invention, into the low temperature heat exchange section, the proportion of which relative to the surface heat exchange is thus increased. Conversely, it is possible to assign the intermediate exchange section 56 to the high temperature cooling circuit.

There is shown in Figure 4 a sectional view of a heat exchange module according to the invention comprising heat distribution means in which the intermediate heat exchange section 56 can be distributed continuously between the fixed section at high temperature 52 and the fixed section at low temperature 54.

The bundle of tubes 50 consists of flat tubes 102 between which are arranged corrugated intermediate elements 104. The tubes 102 are connected at each of their ends to collector plates 106 closed by a cover 108. The tubes 102, the intermediates 104, the collector plates 106 and the covers 108 can be assembled by soldering in a single operation. Alternatively, the covers 108, made for example of plastic, can be mechanically fixed, for example by means of folded tabs, on the collector plates 106.

A transverse partition 110 forming a piston able to move in translation in the manifolds is moved by an endless screw 42 driven in rotation, by example by an electric motor 44 disposed in a housing located outside the heat exchange module. The electric motors 44 are supplied by a cable 112 which brings, at the same time as the electric power necessary for driving the motors, control signals making it possible to control on, off, the speed of rotation and the direction of rotation of the latter.

Thus, the worm 42 cooperating with the piston 110 constitutes the mechanical means for distributing the heat exchange surface 50, while the motor 44 constitutes the power means which drive the mechanical means 42. Each of the pistons 110 can move over a stroke equal to the length of the threaded part of the worm 42. It is the length of the threaded part 42 which determines the extent of the attributable intermediate heat exchange surface 52 which can be distributed between high temperature and low temperature cooling circuits.

In Figure 4, each of the pistons 1.1.0 has been shown in abutment against a shoulder 114 of the rod 42. In other words, in this configuration of the heat distribution means, the whole of the heat exchange surface intermediate heat has been allocated to the high-temperature cooling circuit 2. At its other end, the threaded rod 42 has a stop 116. When the pistons 110, which move simultaneously and in synchronism, come into abutment against the stop 116, the all of the intermediate exchange surface 56 is allocated to the low-temperature cooling circuit 4. In addition, the pistons 110__ can occupy each of the intermediate positions between the extremes described above, so that the distribution of the intermediate exchange surface may vary continuously. It should however be observed that in practice this surface varies in increments because the pistons must be placed between two successive tubes. There is shown in Figure 5 a sectional view of a heat exchange module according to the invention comprising means for adjusting the adjustment of the overall heat exchange surface 50 of the adjustable heat exchange module continuously identical to those of the embodiment shown in Figure 4. However, the heat exchange module of Figure 5 has two rows of tubes instead of one.

The second row of tubes, designated by the general reference 74, shown in section in Figure 5, consists of flat tubes 102 between which are corrugated spacers 104. The tubes are connected to manifold plates 106 closed by lids 108 The first row of tubes (not referenced and not shown) is located behind the second row of tubes and is therefore not visible in the figure. This. first row of tubes can have the same heat exchange surface as row 74, or it can be smaller or larger than it. In the example shown, the first row of tubes is part of the fixed heat exchange section of the low temperature cooling circuit 4.

The coolant at low temperature enters the first row of tubes, as shown by the arrow 63. It traverses these tubes from left to right, according to Figure 5, to reach a manifold (not shown) located behind the cover 108 It emerges from this manifold through a passage orifice 92 so as to enter the low temperature inlet manifold 62 of the second row of tubes 74. It then runs through the tubes 102 from right to left, according to FIG. 5 , to enter the low temperature outlet manifold 64 located to the left of FIG. 5. It will be noted that, in this embodiment, the position of the low temperature inlet and outlet manifolds 62 and 64 is reversed by relative to the position they occupy in the embodiment of Figure 3. Similarly, the communication port 92 is located to the right of Figure 5, while it is located to the left of Figure 3. These differences are explained by the fact that, in the embodiment In Figure 5, the first row of tubes has only one pass. Thus, the coolant at low temperature circulates only once in these tubes while, in the embodiment of Figure 3, it performs a U-shaped path. However, it goes without saying that the first row of tubes could also include two or more passes.

In the embodiment of Figure 5, the mechanical means and the power means 44 which allow the displacement of the partitions 110 are identical to those which have been described with reference to Figure 4. The position of the partitions forming the piston 110 can therefore be adjusted to any intermediate position located between the two ends of the stroke defined by the threaded rod 42.

There are shown in Figures 6 and 7 two detailed sectional views which show the embodiment of means for distributing the heat exchange surface of the heat exchange module of the invention in a discrete manner. In the example shown, these means consist of a transverse partition 122 capable of dividing the manifold into two parts. The partition 122 is moved by an actuator 124 which can be electric, pneumatic, electropneumatic or other.

In the example shown, the actuator 124 is constituted by a piston 126 which is moved, in a cylinder 128, pneumatically or hydraulically. The actuator 124 makes it possible to pass the partition from the retracted position or open position shown in FIG. 6 to the extended position or closed position shown in FIG. 7. When the partition 122 is retracted, the coolant can circulate freely in the manifold. When the partition is in the closed position, the partition closes the manifold. The actuator 124 can actuate the partition 122 in "all or nothing" movement or in a progressive manner. A sealing membrane 130. which envelops the partition 122 makes it possible to establish a seal between the medium inside the manifold and the outside of the heat exchange module. The actuator 124 is disposed outside of the manifold. Its assembly is therefore easy. In addition, as the actuator is isolated from the aggressive internal medium which circulates in the exchanger, it is not corroded and its service life is extended. The thermomechanical stresses on the actuator are reduced. Only the membrane 130 is in direct contact with the heat transfer fluid which circulates in the manifold. The membrane adapts to the shape of the partition 122. It can lengthen in the case where the stroke of the partition 122 is short.

As can be seen in Figures 6 and 7, it can take place when the stroke of the partition 122 would require too much material elongation. In this case, there is no elongation of the material of the membrane and therefore the closing force is lower.

In addition, the risks of leakage are reduced because the membrane provides a good seal. This tightness can, moreover, be easily checked from outside the heat exchange module.

In addition, the fact that the actuator 124 is outside the manifold reduces the pressure drops, which is an additional advantage of this embodiment.

FIGS. 8a to 8e show the successive stages of a variation in the distribution of the heat exchange surface between the high temperature circuit and the low temperature circuit by means of partition walls such as the partitions 122 shown in Figures 6 and 7. The heat exchange module shown in these figures schematically comprises a single row of tubes, but it goes without saying that it could include more, for example two or three, as described previously.

In the example shown, the heat exchange module has four partition walls distributed two by two. The two partitions 122 located at the top of the exchanger and the two partitions 122 located at the bottom of the exchanger, respectively, operate simultaneously. In the position shown in Figure 8a, the two upper partitions 122 are closed. They close off the manifold (position shown in Figure 7). The two lower partitions are open (see Figure 6). The partition walls 122 thus ensure a division of the overall heat exchange surface of the heat exchange module into three parts.

At the top there is a high temperature heat exchange section 52; at the lower part of the exchanger, a low temperature heat exchange section 54 and between these two sections an intermediate heat exchange section attributable to one or the other of the high temperature and low circuits temperature 56. The high temperature fluid enters section 52 (arrow 59), crosses this section from left to right, as shown by arrow 55, then exits at 61. The low temperature fluid enters section 54, as shown diagrammatically by arrow 63, crosses this section from left to right, as diagrammed by arrow 57, and emerges from the low-temperature manifold 64, as diagrammed by arrow 65.

In the position of Figure 8a, the intermediate heat exchange section is assigned to the low circuit temperature 4. As shown in FIG. 8b, to assign this intermediate section to the high temperature circuit, the two partitions 122 located at the bottom of the exchanger are closed simultaneously.

In FIG. 8c, the closure is completed, so that the intermediate exchange surface 56 is isolated from both the high temperature circuit and the low temperature circuit. This situation constitutes an intermediate state, the duration of which is generally less than one second. This intermediate state can possibly be eliminated if one wishes to create a mixture between the two circuits or manage and balance the pressures between the circuits. We then open the two upper partition walls, as shown in Figure 8d.

In Figure 8e, the two upper partitions are fully open and the high temperature fluid now occupies the heat exchange surface 56 previously allocated to the low temperature circuit. A change in the distribution of the overall heat exchange surface 50 of the heat exchange module of the invention has thus been produced. The exchange surface allocated to the high temperature circuit has been increased and correspondingly, - the heat exchange surface allocated to the low temperature circuit has been reduced.

Of course, it is possible to return to the reverse distribution by first closing the two upper partitions, then by opening the two lower partitions.

In the example shown schematically in Figures 8a to 8e, the heat exchange module has only four partition walls 122, that is to say only two partitions for each manifold. In this way, the intermediate exchange surface 56 can only be allocated by whole to the high temperature circuit or to the low temperature circuit. However, it goes without saying that the heat exchange module of the invention could comprise more than two partitions for each manifold, for example three, four, five or more. This would allow the intermediate heat exchange surface to be distributed in variable proportions between the two circuits. For example, one third of the intermediate exchange surface could be allocated to the high temperature circuit and two thirds of this surface to the low temperature circuit. It goes without saying that the greater the number of partition walls, the more it is possible to carry out a fine distribution of the heat exchange surface.

There is shown in Figures 9, 10 and 11 an embodiment of a circular partition wall. A fixing flange 132 is fixed to the cover 108 of the manifold. A bell 134 having a flange 136 complementary to the fixing flange 132 is placed on the latter. The sealing membrane 130 is clamped between the fixing flange 132 and the flange 136 of the bell 134. The flange 132 and the flange 136 are held by fixing clips 136 or by any other similar means. The membrane 130 comprises a stud 142 which engages in a hole 14.3 of a piston 144. The piston comprises at its upper part an actuating rod 146 which is connected to the actuator 124 placed on the bell 134.

There is shown in Figures 12 and 13 a variant of the embodiment of Figures 9 to 11. In this embodiment, the partition wall has an elongated shape instead of being circular.

Another embodiment of the invention is shown in Figures 14 to 16. It differs from the embodiments described above by the fact that it does not include means for partitioning a manifold allowing distribute the volume of this manifold continuously or incrementally between the high-temperature and low-temperature circuits, but switching means which make it possible to connect "all or nothing" a row of tubes to one or the other of its two cooling circuits.

In Figure 14, the heat exchange module designated by the general reference 122 consists of three rows of tubes, namely a first row of tubes 152, a second row of tubes 154 and a third row of tubes 156 disposed between row 152 and row 154. The rows of tubes 152, 154 and 156 are crossed by the same air flow, as shown by arrow 158.

In the example shown, the first row of tubes is a row of high temperature tubes and the second row of tubes a row of low temperature tubes. The tubes of the first row have, at one end, a high temperature inlet manifold 58, and at their other end a high temperature outlet manifold 60. The high temperature fluid enters the box inlet manifold 58 by an inlet manifold, as shown schematically by the arrow 59, and it emerges from the outlet manifold by an outlet manifold, as shown schematically by the arrow 61, after having crossed from left to right, according to Figure 14, the first row tubes 152.

Similarly, the fluid at low temperature enters the inlet manifold 62 through an inlet manifold, as shown in the arrow 63, and emerges from the outlet manifold 64, as shown schematically by the arrow 65, after having traversed from left to right, according to FIG. 14, the tubes of the second row of tubes 154.

A passage orifice 162 allows a passage of the fluid between the manifold 62 and the box 66; a passage orifice 164 allows fluid communication between the outlet manifold 64 and the box 68; a passage orifice 166 allows passage of the fluid between the intermediate inlet manifold 66 and the inlet manifold 58; finally, a passage orifice 168 allows communication between the intermediate outlet manifold 68 and the outlet manifold 60. Switching means make it possible to selectively open or close the passage orifices 162, 164, 166, 168. In the example shown, the means which allow the closing and opening of the passage orifices 162 and 166, located opposite one another, are constituted by a valve 172 disposed in the intermediate chamber 66, between the orifices 162 and 166. The valve 172 is mounted on a rod 174 driven by an actuator 176 located outside of the manifold 58.

Similarly, the switching means which make it possible to close and open the communication orifice 164 and the communication orifice 168 are constituted by a valve 180 located in the intermediate chamber 68. The valve 180 is mounted on a rod 182 driven by an actuator 184 also located outside of the outlet manifold 60.

Of course, this embodiment is not limiting and one could consider other switching means, for example valves located in the manifolds 62 and 58 and in the manifolds 60 and 64, respectively.

In Figure 14, the valve 172 closes the passage orifice 162, while the valve 180 closes the orifice. of passage 1-64. In this way, the tubes of intermediate row 156 are isolated from the low temperature circuit. The tubes of the intermediate row are therefore attached to the high temperature stage by a communication of the fluid through the passages 166 and 168. After its entry into the inlet manifold 58, the fluid is distributed between the two rows of tubes 152 and 156, then comes out by the single tube provided on the outlet manifold 60, as shown by arrow 61.

On the contrary, in FIG. 15, which represents a detailed view of the right end of the heat exchange module 122 shown in FIG. 14, the valve 180 closes the passage orifice 168. It must be imagined that, from in the same way, the valve 172 (not shown) closes the passage orifice 166 situated between the manifolds 58 and 66. Under these conditions, the tubes of the first row 152 are insulated and the tubes of the intermediate row 156 are attached to the circuit at low temperature. The circulation of the fluid takes place as described above by changing what must be changed.

The switching means which have just been described therefore make it possible to distribute the overall heat exchange surface of the heat exchange module 122, this overall heat exchange surface being constituted by the sum of the heat exchange surfaces of heat of each of the three rows 152, 154 and 156. The tubes of rows 152 and 154 always belong, respectively, to the high temperature circuit and to the low temperature circuit, while the tubes of the intermediate row can be assigned to one either of these two circuits. However, unlike the previous embodiments, the tubes of row 156 are allocated "all or nothing". Their heat exchange surface cannot be divided between the high temperature circuit and the low temperature circuit.

There is shown in Figure 17 a perspective view of a _^ heat exchange module according to the invention having a row of U-tubes 190, also called tubes hairpin, each formed by two branches 192 and 194 connected by an elbow 196. A corrugated interlayer 198 is placed between two successive U-shaped tubes. The arms 192 of the tubes communicate with an attributable inlet manifold 66, while the branches 194 communicate with an attributable outlet manifold 68. The manifolds 66 and 68 are formed respectively from two tubes 200 and 202 arranged parallel to each other and preferably in a substantially horizontal position.

The inlet manifold 66 is provided with an inlet manifold 204 adapted to be connected to a high temperature circuit and another inlet manifold 206 suitable for being connected to a low temperature circuit. In addition the outlet manifold 68 is provided with an outlet pipe 208 suitable for being connected to said high temperature circuit and another outlet pipe 210 suitable for being connected to said low temperature circuit.

In each of the manifolds 66 and 68 is slidably mounted a piston 212 able to move in translation by an endless screw 214 driven in rotation. The internal surface of the tubes 200 and 202 is treated with a material, for example of the polytetrafluoroethylene (PTFE) type, facilitating the sliding of the pistons 212 forming distributors. These pistons each receive a peripheral seal 216, advantageously made of PTFE, to ensure the seal between the high temperature part and the low temperature part.

An interface box 218 (FIG. 18) ensures the connection of the U-shaped tubes 190 with the manifold 66 and the manifold 68. The sealing between each U-shaped tube is ensured by a partition made by stamping, in order to avoid an overflow of the tubes in the manifolds, which guarantees perfect sliding of the pistons 212.

The worms 214 are driven synchronously by an electric motor 220, for example of the stepping type, and by means of a transmission 222, for example a belt or a servo gear. The electric motor 220 can be placed in a housing located outside the heat exchange module or else integrated into the module, for example embedded in the fluid circulating in the module.

Thus, the worms 214 cooperating with the pistons 212 constitute the mechanical means for distributing the heat exchange surface 50, while the motor 220 constitutes the power means which drive these mechanical means. The pistons 212 thus move in synchronism over a stroke equal to the length of the threaded portion of the worms. The extent of the heat exchange surface can thus be distributed between the high temperature and low temperature cooling circuits.

A stop 224 (Figure 19A) fixes the extreme position of the pistons 212, to ensure a minimum exchange surface for the high temperature circuit, for example for the cooling of the engine.

The sliding movement of the pistons 212 can be regulated in different ways, for example by generating a position signal, but preferably with a stepping motor.

Figures 19A to 19F show different positions of the pistons 212 from that of Figure 19A where the high temperature circuit has a minimum heat exchange surface to that of Figure 19F where the high temperature circuit has a heat exchange surface Max.

The module in Figure 17 allows the exchange surface to be adapted according to need, and this in a progressive and flexible manner.

Claims

claims

1. Heat exchange module for a motor vehicle with a thermal engine equipped with a high temperature cooling circuit (2), in particular for cooling the engine (8), and a low temperature cooling circuit ( 4) for vehicle equipment (32), the module (22, 122) comprising at least one row of heat exchange tubes (50, 152, 154, 156) connected to at least one inlet manifold ( 58, 62) and at least one outlet manifold (60, 64), these tubes forming a heat exchange surface (50), characterized in that it comprises surface distribution means (40, 42 , 44, 46) which make it possible to split, advantageously in a modular manner, the heat exchange surface (50) into a high temperature heat exchange section used for cooling the high temperature circuit and a section of low temperature heat exchange used for cooling the circuit at b enough temperature.

2. Heat exchange module according to claim 1, characterized in that it comprises a fixed heat exchange section at high temperature (52) permanently integrated into the high temperature cooling circuit (2); a fixed low temperature heat exchange section (54) permanently integrated into the low temperature cooling circuit (4) and an attributable heat section (56) comprising an attributable inlet manifold box (66) and a box assignable output manifold (68) which can be assigned in whole or in part, either to the fixed heat exchange section at high temperature (52), or to the fixed heat exchange section at low temperature (54 ).

3. Heat exchange module according to claim 2, characterized in that it comprises a single row of tubes.

4. heat exchange module according to claim 2, characterized in that it comprises a first and a second row of tubes (72, 74), the first of these rows (72) belonging either to the exchange section fixed heat (52) from the high temperature circuit, i.e. the fixed heat exchange section (54b) of the low temperature cooling circuit, the second row of tubes (72) being split into a fixed high temperature section (52), in a fixed low temperature section (54b) and an attributable intermediate heat section (56), the high temperature section, respectively the low temperature section, being connected in series to the first row of tubes (72) .

5. heat exchange module according to claim 2, characterized in that it comprises three rows of tubes, the first row (152) belonging to the fixed heat exchange section of the high temperature circuit (2), the second row (154) belonging to the fixed exchange section of the low temperature circuit (4), the third row (156) belonging to the attributable intermediate heat exchange section.

6. Heat exchange module according to claim 2, characterized in that it comprises a row of U-shaped tubes () each of which communicates on the one hand with the attributable inlet manifold (66) and on the other leaves with the attributable outlet manifold (68).

7. heat exchange module according to one of claims 2 to 6, characterized in that the surface distribution means (42) are constituted by adjustable partition means (110; 212) of the manifold attributable input (66) and by adjustable partition means (110; 212) of the attributable outlet manifold (68), these partitioning means allowing the assignable input manifold (66) to be modularly divided into an entry room attributable to high temperature and a room inlet attributable to low temperature, and the outlet manifold assignable to an outlet chamber assignable to high temperature and an outlet chamber assignable to low temperature, the distribution of the assignable inlet manifold (66) and the attributable outlet manifold (68) between these chambers being adjustable.

8. Heat exchange module according to claim 7, characterized in that the partitioning means of the assignable inlet manifold box (66) and of the assignable outlet manifold box (68) are continuously adjustable.

9. heat exchange module according to claim 8, characterized in that the continuously adjustable partition means consist of a piston (110; 212) slidably mounted in the attributable inlet manifold (66) and by a sliding piston (110; 212) mounted in the attributable outlet manifold (68), these pistons being moved by actuation means (44; 220).

10. Heat exchange module according to claim 8, characterized in that the actuation means consist of endless screws (42; 214) driven in rotation by actuators (44) external to the manifolds (62, 64).

11. Heat exchange module according to claim 7, characterized in that the partitioning means of the attributable inlet manifold box (66) and of the attributable outlet manifold box are discreetly adjustable.

12. Heat exchange module according to claim 11, characterized in that the discretely adjustable partition means consist of a series of partitions (122) actuated by actuators (124) distributed over the length of the attributable inlet manifold (66) and along the length of the attributable outlet manifold (68), each of these partitions (122) being capable of dividing the attributable inlet manifold (66), respectively the attributable outlet manifold (68), in two chambers.

13. Heat exchange module according to claim 12, characterized in that the partitions (122) are isolated from the fluid medium of the heat exchange module (22, 122) by sealing membranes (130) and in that they are actuated by actuators (124) external to the two manifolds (66, 68).

14. heat exchange module according to one of claims 2 to 6, characterized in that it comprises switching means (172, 180) which allow to connect the attributable heat exchange surface (156) in all, either to the fixed heat exchange section at high temperature (152), or to the fixed heat exchange section at low temperature (154).

15. A heat exchange module according to claim 14, characterized in that the switching means consist of passage orifices (162, 164, 166, 168) provided between the manifolds of the fixed sections at high temperature and at low temperature and the manifolds of the attributable intermediate heat exchange section, and by valves (172, 180) which allow to selectively open or close these passage openings.

16. A heat exchange module according to claim 15, characterized in that the valves (172, 180) are connected by a rod (174, 182) to a control member (176, 184) outside the manifolds (58 , 60).

17. Heat exchange module according to one of claims 1 to 16, characterized in that it comprises logic means (46) for controlling the means for distributing the heat exchange surface (42) which receive information on control parameters such as the water temperature high temperature (2) and low temperature (4) circuits, the engine load, the engine speed, the power rejected by the engine (8) on the water, at least one of these parameters governing the distribution of heat exchange surface.

18. Heat exchange module according to one of claims 4 to 17, characterized in that it comprises cooling fins (104) common to all the rows of the module.

19. Heat exchange module according to one of claims 4 to 18, characterized in that the manifolds consist of a manifold plate and a cover assembled by brazing.

20. Heat exchange module according to one of claims 4 to 18, characterized in that the manifolds consist of a manifold plate and a cover, in particular of plastic, mechanically fixed on the manifold.

21. A thermal energy management system developed by a thermal engine of a motor vehicle, comprising a high temperature cooling circuit (2) comprising a high temperature radiator for cooling the engine (8) of the vehicle and a cooling circuit at low temperature comprising a low temperature radiator for cooling vehicle equipment (32), characterized in that the high temperature radiator consists of the high temperature heat exchange section of a heat exchange module (22) according to one of claims 1 to 20, and in that the low temperature radiator is constituted by the low heat exchange section temperature of this same module.

22. A thermal energy management system according to claim 21, characterized in that it comprises logic means (46) for controlling the distribution means (42) of the heat exchange surface coupled with management by a four-way valve (12) for cooling the engine (8), the valve (72) comprising an inlet channel (12-1) at the engine outlet (8), and three outlet channels, a first channel ( 12-2) connected to the air heater (18), a second channel (12-3) connected to the heat exchange module (22), and a fourth channel (12-4) connected to the short-circuit pipe (24).