WO2021058891A1

WO2021058891A1 - Thermal management system for a motor vehicle

Info

Publication number: WO2021058891A1
Application number: PCT/FR2020/051565
Authority: WO
Inventors: Mohamed Yahia
Original assignee: Valeo Systemes Thermiques
Priority date: 2019-09-24
Filing date: 2020-09-10
Publication date: 2021-04-01
Also published as: FR3101020A1

Abstract

Thermal management system (1) for a vehicle, comprising at least a refrigerant circuit (3) and a loop (2) for heat-transfer fluid, the circuit (3) comprising at least a first heat exchanger (5) and a second heat exchanger (7), the loop (2) comprising a radiator (22) which effects heat exchange with the flow of air FA1 exterior to the passenger compartment and which is disposed upstream of the first heat exchanger (5) in a direction of circulation S3 of the flow of exterior air FA1, the system (1) comprising at least one heat exchanger (8) disposed on the refrigerant circuit (3) between the first heat exchanger (5) and the second heat exchanger (7), the heat exchanger (8) and the radiator (22) being disposed in the loop (2) for heat-transfer fluid such that the radiator (22) discharges heat energy picked up by the heat exchanger (8) into the flow of exterior air (FA1).

Description

HEAT TREATMENT SYSTEM FOR A VEHICLE

AUTOMOTIVE

The present invention relates to the field of heat transfer fluid loops operating with a refrigerant fluid circuit. The subject of the invention is a heat treatment system comprising at least one heat transfer fluid loop and a refrigerant fluid circuit.

A refrigerant circuit is generally associated with a ventilation, heating and / or air conditioning installation of a vehicle interior to heat treat a flow of air outside the vehicle heading towards the interior. Indeed, such a circuit allows, using changes of state of the refrigerant fluid to heat and / or cool the air flow sent inside the ventilation, heating and / or air conditioning installation. .

On the other hand, a heat transfer fluid circuit is generally associated with at least one of the elements of the powertrain of the vehicle to be cooled. For this, the heat transfer fluid, being of a different nature from the refrigerant, needs to be cooled in order to be able to heat treat the powertrain. For this purpose, the heat transfer fluid is generally cooled by a flow of air outside the vehicle interior.

It is also known practice to cool the heat transfer fluid which circulates in this traction chain of the vehicle by using the refrigerant circuit mentioned above. In such a case, a heat exchanger is arranged at an interface between the coolant circuit and the coolant circuit. This heat exchanger is installed in series with the other components that make up the refrigerant circuit.

These cooling systems can for example be integrated on vehicles whose traction chain is electric, that is to say that it comprises at least one motor operating at least partially on electric energy and controlled by an electronic box. control. In addition, these electric motors are currently supplied electrically by one or more electrical storage devices on board the vehicle. All of these elements do not withstand excessively large temperature changes and should therefore be cooled. We understands that hybrid or electric vehicles require increasingly efficient cooling systems.

These cooling systems are most often arranged at least in part on the front face of the vehicles. More exactly, these cooling systems conventionally comprise at least one heat exchanger which is arranged at this front face. In particular in order to optimize the efficiency of the heat treatment system, said heat exchanger can be configured to provide sub-cooling of the liquid refrigerant when it is used as a condenser.

Additionally, the heat transfer fluid loop of said vehicles conventionally comprises at least one radiator, the heat transfer fluid loop and the refrigerant fluid loop being arranged so that at least the heat exchanger is disposed upstream of the radiator with respect to the direction of flow. circulation of the flow of exterior air entering the front of the vehicle. In such architectures, when the heat treatment system operates as an air conditioning installation, the flow of outside air is successively involved in heat exchanges with the refrigerant fluid circulating in the heat exchanger, then with the radiator.

However, it may be necessary to reverse such an architecture so that the radiator is arranged upstream of the heat exchanger, depending on the direction of circulation of the flow of air outside the passenger compartment through this radiator and this heat exchanger. A drawback of such an architecture lies in the fact that the heat exchanger is incapable of providing sub-cooling of the refrigerant fluid after its condensation phase.

The present invention falls within this context and aims to solve such a problem by proposing a heat treatment system, the radiator of which is arranged upstream of at least one heat exchanger according to the direction of circulation of the external air flow, the heat exchanger. heat treatment system being able to ensure the sub-cooling of the refrigerant fluid.

The present invention thus relates to a heat treatment system intended for a vehicle comprising at least one refrigerant fluid circuit and at least one heat transfer fluid loop; the refrigerant fluid circuit comprising at least a first heat exchanger and a second heat exchanger, the first heat exchanger being configured to implement a heat exchange between the refrigerant fluid and a flow of air outside the passenger compartment of the vehicle and the second heat exchanger being configured to implement a heat exchange between the coolant and an interior air flow intended to be sent into the passenger compartment,

- the heat transfer fluid loop comprising at least one radiator configured to implement heat exchange between the external air flow and the heat transfer fluid,

- the heat treatment system comprising at least one heat exchanger configured to implement a heat exchange between the refrigerant fluid circulating in the circuit and the heat transfer fluid circulating in the loop, the heat treatment system being characterized in that the the heat exchanger is arranged on the refrigerant circuit between the first heat exchanger and the second heat exchanger, the heat exchanger and the radiator being arranged in the heat transfer fluid loop so that the radiator discharges into the flow outside air from the calories captured by the heat exchanger.

The heat transfer fluid is advantageously a heat transfer liquid, such as for example a glycol water.

In particular, the radiator of the heat transfer fluid loop is placed directly upstream of the heat exchanger of the refrigerant circuit according to the direction of circulation of the flow of external air which enters the front face of the vehicle so that the flow of The air heated by heat exchange with the radiator is sent directly to the first heat exchanger.

The refrigerant circuit of the heat treatment system according to the invention is configured to operate alternately in heat pump mode, so as to heat the interior air flow before sending it into the passenger compartment, or in air conditioning mode, in order to cool the interior air flow before sending it into the passenger compartment.

Depending on the operating mode of the heat treatment system circuit according to the invention, the first heat exchanger is configured to operate as a condenser or as an evaporator, with respect to the refrigerant fluid. In particular, the first heat exchanger is configured to be used as a condenser when the circuit is operating in air conditioning mode and as an evaporator when the circuit is operating in heating mode. In other words, when the circuit operates in air conditioning mode, the refrigerant circulating in the heat exchanger transfers calories to the flow of outside air and when the circuit operates in heating mode, the refrigerant circulating in the heat exchanger. heat captures calories from the outside air flow. According to the invention, the heat exchanger of the circuit is configured to ensure the sub-cooling of the refrigerant fluid. The term “sub-cooling” is understood to mean the lowering of the temperature of the refrigerant fluid below its condensation temperature.

According to one aspect of the invention, the heat exchanger is arranged in the heat transfer fluid loop downstream of the radiator, according to the direction of circulation of the heat transfer fluid in the heat transfer fluid loop.

The calories transferred by the coolant into the radiator by heat exchange with the flow of outside air ensure that the coolant enters the heat exchanger at a temperature significantly lower than the temperature of the coolant entering this heat exchanger. heat.

According to another aspect of the invention, the heat exchanger is arranged in the heat transfer fluid loop upstream of the radiator, according to the direction of circulation of the heat transfer fluid in the heat transfer fluid loop.

The calories captured by the coolant at the heat exchanger are discharged into the outdoor air flow via the radiator, which ensures a return of the coolant at a temperature significantly lower than the temperature of the coolant entering the heat sink. the heat exchanger.

Such arrangements contribute in particular to improving the thermal efficiency of the circuit in which this coolant circulates. In particular, the sub-cooling is implemented when the refrigerant circuit operates in air conditioning mode, that is to say when the refrigerant is brought to the predominantly liquid state in the heat exchanger. According to one characteristic of the invention, the refrigerant fluid circuit is a closed circuit which comprises at least one main branch on which are arranged at least one compression device, the first heat exchanger, the second heat exchanger and at least one control member. expansion, said primary expansion member, arranged between the heat exchanger and the second heat exchanger, the radiator being arranged upstream of the first heat exchanger in the direction of circulation of the flow of outside air.

It is understood that the term "primary" is here associated with the arrangement of the primary expansion member on the main branch of the refrigerant circuit and not with any hierarchy of components of the heat treatment system. Likewise, the qualifiers "first", "second" are intended to distinguish similar elements of the said system and do not confer an order of importance on these elements.

Within the refrigerant circuit, the second heat exchanger can be configured to perform a function opposite to that of the first heat exchanger. In other words, for example, when the first heat exchanger is used as a condenser, the second heat exchanger functions as an evaporator and vice versa.

In particular, the heat exchanger is arranged on the refrigerant circuit between the first heat exchanger and the primary expansion member.

According to one characteristic of the invention, the refrigerant fluid circuit comprises a secondary branch which extends between a first point of divergence, comprised between the heat exchanger and the second heat exchanger, and a first point of convergence, comprised between the second heat exchanger and the compression device, the secondary branch comprising at least one secondary expansion member and a secondary heat exchanger thermally coupled to an electrical storage device of the vehicle.

By “thermally coupled” is meant the fact that the secondary heat exchanger is configured to allow direct or indirect cooling of the electrical storage device. For example, the secondary heat exchanger can be configured to implement a heat exchange between the refrigerant fluid and the electrical storage device, the latter then being arranged in contact with this. secondary heat exchanger. Alternatively, the heat exchanger can be configured to implement a heat exchange between the refrigerant fluid and the heat transfer liquid included in a second loop of the heat treatment system, the second loop comprising this electrical storage device. The term “secondary” is here associated with the location of the so-called “secondary” elements on the secondary branch of the circuit. The refrigerant circuit thus comprises at least one point of divergence, called the first point of convergence, located between the secondary branch and the main branch, and at least one point of convergence, called the first point of convergence, located between these same secondary branch. and main branch, so that the secondary heat exchanger is arranged in parallel with the second heat exchanger. In particular, the first point of divergence is arranged between the heat exchanger and the second heat exchanger, more particularly between the heat exchanger and the primary expansion member, while the first point of convergence is positioned between the second exchanger thermal and compression device.

Thus, depending on the operating mode implemented, the heat treatment system can be configured so as to ensure the simultaneous circulation of the refrigerant fluid in:

- the second heat exchanger of the main branch, for example in air conditioning mode;

- the second heat exchanger of the main branch and in the secondary heat exchanger of the secondary branch, for example in order to simultaneously ensure the air conditioning mode and the cooling of the electrical storage device. According to one characteristic of the invention, the coolant circuit comprises a tertiary branch which branches off the coolant from the branch the main branch between the heat exchanger and the primary expansion member and brings it to the main branch in a second point of convergence located downstream of the compression device, between the compression device and the first heat exchanger, the tertiary branch comprising at least one tertiary expansion member.

In particular, the tertiary branch can provide such a bifurcation at the level of the first point of divergence of the secondary branch and of the main branch. Alternatively, the point of divergence of the main branch and / or of the secondary branch and / or of the tertiary branch can be replaced by a valve, for example a three-way valve.

The heat treatment system thus comprises at least two points of convergence, the first point of convergence connecting the secondary branch to the main branch, and a second point of convergence connecting the tertiary branch to the main branch, the compression device being interposed between the first point of convergence and the second point of convergence.

The tertiary branch may, depending on the operating mode of the refrigerant circuit, make it possible to bypass the second heat exchanger and send the refrigerant fluid leaving the heat exchanger to the first heat exchanger without the latter circulating at through the second heat exchanger and the compression device. This bypass can in particular be carried out when the circuit is operating in heating mode in order to send a flow of hot air into the vehicle interior, via the heat transfer fluid loop.

In other words, this tertiary branch allows on the one hand the heat treatment system to operate alternately in heating mode or in air conditioning mode depending on the demand of the occupants of the vehicle interior and on the other hand to prevent that, when the circuit operates in heating mode, the refrigerant does not unnecessarily pass into the second heat exchanger.

In such an embodiment of the present invention, the heat treatment system is thus configured so that the refrigerant fluid circulates in the same direction of circulation in the first heat exchanger, independently of the operating mode of the refrigerant fluid circuit, that is, regardless of whether the first heat exchanger is used as a condenser or as an evaporator.

According to an alternative architecture of the treatment system, the refrigerant circuit can comprise a tertiary branch which branches off the refrigerant fluid from the main branch between the heat exchanger and the primary expansion member and brings it to the main branch in a second point of convergence located downstream of the first heat exchanger, between this first heat exchanger and the heat exchanger, the tertiary branch comprising at least one tertiary relaxation.

Similar to the heat treatment system previously exposed, the tertiary branch of the heat treatment system of the present embodiment may, depending on the operating mode of the refrigerant circuit, allow bypassing the second heat exchanger and send the outgoing refrigerant fluid. from the heat exchanger to the first heat exchanger without it circulating in the second heat exchanger. As before, the tertiary branch can provide such a bifurcation at the level of the first point of divergence of the secondary branch and of the main branch. Such an alternative architecture of the heat treatment system ensures that the refrigerant fluid circulates in opposite directions of flow at the level of the first heat exchanger depending on whether the refrigerant circuit operates in air conditioning mode or in heating mode, that is to say depending on whether the first heat exchanger is used as a condenser or as an evaporator respectively and therefore depending on whether the refrigerant fluid enters the first heat exchanger in the gaseous state or in the liquid state.

Thus, by way of example, when the refrigerant circuit operates in air conditioning mode, the gaseous or essentially gaseous refrigerant fluid can enter the first heat exchanger at a first end of the first heat exchanger while when the circuit is operating. in heating mode, the refrigerant circuit, at least partly liquid, can enter the first heat exchanger at a second end, opposite to the first end.

Regardless of the embodiment implemented, according to one characteristic of the invention, the refrigerant circuit can include a bypass branch which diverges from the main branch downstream of the compression device, between this compression device and the first heat exchanger. , the bypass branch having a point of connection with said main branch located between the first heat exchanger and the heat exchanger, downstream of the first heat exchanger and of a non-return valve. It will be noted that such a non-return valve is arranged between the point of connection with the main branch located between the first heat exchanger and the heat exchanger and a second point divergence located between the first heat exchanger and the heat exchanger.

In particular, the branch branch branches off from the main branch at a point called the branch point.

According to the invention, the main branch and / or the bypass branch include at least one refrigerant fluid flow regulator arranged between the compression device and the first heat exchanger.

For example, the refrigerant flow regulators can be valves. It is understood that these refrigerant fluid flow regulators make it possible to selectively direct the refrigerant fluid to the main branch or to the bypass branch by allowing and preventing the circulation of this refrigerant fluid in one or the other of these. branches.

According to an exemplary embodiment, there are two two-way valves, one being installed in the main branch and the other being installed in the bypass branch. Alternatively, the heat treatment system can include a three-way valve installed at the bifurcation point.

In other words, the bypass branch associated with the refrigerant flow rate regulators can make it possible to bypass or not the first heat exchanger depending on whether it is necessary to send a hot air flow or a hot air flow. cold air respectively in the vehicle interior. In other words, this bypass branch allows the heat treatment system to operate alternately in heating pump mode or in air conditioning mode according to demand.

According to the invention, the heat transfer fluid loop is a closed loop which comprises at least one main line, on which are at least arranged the radiator, the heat exchanger and a member for circulating the heat transfer fluid, and at least a bypass line which diverges from the main line between the heat transfer fluid circulation member and the radiator, the bypass line having a junction point with said main line arranged between the radiator and the heat exchanger. According to the invention, the bypass line comprises at least one unit heater configured to implement a heat exchange between the coolant and the air flow. interior.

Particularly, the heat treatment system can comprise at least one three-way valve configured to control the circulation of the heat transfer fluid towards the main line and / or the bypass line of the heat transfer fluid loop. Alternatively, the heat transfer fluid loop can comprise a third point of divergence associated with at least two flow regulating members, for example valves, respectively arranged on the main line and the bypass line.

The bypass line makes it possible in particular to bypass the air heater so that, depending on whether the refrigerant circuit implements the air conditioning mode or the heating mode, the bypass line respectively ensures the bypass of the air heater or the passage of the heat transfer fluid through it.

According to one characteristic of the invention, the heat transfer fluid loop comprises at least one additional heat transfer fluid circulation line which comprises at least one heat exchanger dedicated to the heat treatment of at least one element of the electric traction chain of the motor vehicle. .

In particular, the additional line of the heat transfer fluid loop can be intended for cooling at least one electric motor of the vehicle and / or a control module of this electric motor via a heat exchanger coupled to any of these components.

According to the invention, the heat treatment system may further include an internal heat exchanger arranged between two distinct portions of the refrigerant fluid circuit, in particular a first portion, included between the compression device and the primary expansion member, at the level of which the refrigerant fluid is subjected to a high pressure and a second portion of the refrigerant fluid circuit, between the primary expansion member and the compression device, in which the refrigerant fluid is subjected to a low pressure, less than the high pressure.

Advantageously, this internal heat exchanger makes it possible, on the one hand, to heat the refrigerant fluid upstream of the compression device so that this refrigerant fluid is exclusively in gaseous form when it reaches an inlet of the compressor. compression device and on the other hand to cool the refrigerant upstream of the primary expansion member so that the pressure drop operated by this expansion member is facilitated. The overall efficiency of the refrigerant fluid circuit is thus improved in the presence of this internal heat exchanger. An object of the present invention also relates to a motor vehicle comprising at least one heat treatment system as described above.

Other characteristics, details and advantages will emerge more clearly on reading the detailed description given below as an indication in relation to the various embodiments illustrated in the following figures:

Figure 1 is a schematic representation of a heat treatment system according to the present invention, this heat treatment system comprising at least one refrigerant circuit and a loop of a heat transfer fluid;

Figure 2 schematically illustrates a first example of the operation of the heat treatment system shown in Figure i in which the refrigerant circuit operates in passenger compartment cooling mode;

Figure 3 schematically illustrates a second example of operation of the heat treatment system shown in Figure 1 in which the refrigerant circuit operates in cooling mode of an electrical storage member of the vehicle;

Figure 4 schematically illustrates the heat treatment system shown in Figure 1 according to a third example of operation in which the refrigerant circuit operates in passenger compartment heating mode;

Figure 5 schematically illustrates the heat treatment system shown in Figure 1 according to a fourth example of operation in which the refrigerant circuit operates in passenger compartment heating and heat recovery mode;

FIG. 6 schematically illustrates the heat treatment system shown in FIG. 1 according to a fifth example of operation in which the refrigerant circuit operates in a first mode of demisting the passenger compartment; FIG. 7 schematically illustrates the heat treatment system shown in FIG. 1 according to a sixth example of operation in which the refrigerant circuit operates in a second mode of demisting the passenger compartment;

Figure 8 is a schematic representation of a heat treatment system according to the present invention made according to an alternative embodiment;

Figure 9 schematically illustrates the alternative heat treatment system shown in Figure 8 according to the third example of operation in which the refrigerant circuit operates in passenger compartment heating mode.

FIG. 1 schematically illustrates a heat treatment system 1 of several functions of a motor vehicle, among which there is at least one installation for ventilation, heating and / or air conditioning of the passenger compartment 40, an electrical storage device 9 and at least part of an electric traction chain of the vehicle.

The heat treatment system 1 comprises a heat transfer fluid loop 2, for example glycol water, and a refrigerant fluid circuit 3 which is intended in particular for the heat treatment of a vehicle interior.

Throughout the description, the terms “upstream”, “downstream”, “inlet” and “outlet” refer to a direction of flow Si of the heat transfer fluid in the heat transfer fluid loop 2 or to a direction of flow S 2 of the refrigerant fluid in the refrigerant fluid circuit 3 or of a flow direction S3 of a flow of air from outside the passenger compartment.

The refrigerant fluid circuit 3 consists of a closed circuit which comprises at least one main branch 310 on which are arranged a compression device 4, intended to raise the pressure of the refrigerant fluid, at least a first heat exchanger 5 configured to implement a heat exchange between the refrigerant fluid and the air flow outside the passenger compartment, at least one expansion member 6, called the primary expansion member 61, intended to reduce the pressure of the refrigerant fluid, and at least a second heat exchanger 7 intended to heat treat an interior air flow FA2, distinct from the exterior air flow FAi, and which is intended to be sent into the vehicle interior. The heat transfer fluid loop 2 consists of a closed loop comprising a circulation member 21 of the heat transfer fluid, such as a pump, and at least one radiator 22 configured to implement a heat exchange between the flow of outside air. FAi to the passenger compartment and the heat transfer fluid. Within the heat treatment system 1, the radiator 22 of the heat transfer fluid loop 2 and the first heat exchanger 5 of the refrigerant fluid circuit 3 are exposed to the external air flow FAi, the radiator 22 being arranged upstream of the first heat exchanger 5 according to the direction of circulation S3 of the external air flow FAi. Advantageously, the radiator 22 and the first heat exchanger 5 are arranged on the front face of the vehicle, but they could also be installed on a roof of the vehicle, in a rear wing and in general in all areas of the vehicle which can be swept. by the external air flow FAi.

The first heat exchanger 5 is configured to be used as a condenser or as an evaporator depending on the operating mode of the refrigerant fluid circuit 3 operated, that is to say an air conditioning mode or a heating mode. Depending on the operating mode implemented, the refrigerant fluid which circulates in this first heat exchanger 5 has different states. Indeed, when the refrigerant fluid circuit 3 operates in air conditioning mode, the first heat exchanger 5 operates as a condenser, that is to say the refrigerant fluid enters this first heat exchanger 5 in the gaseous state, is cooled by heat exchange with the external air flow FAi and comes out in the liquid state. Conversely, when the refrigerant circuit 3 operates in heating mode, the first heat exchanger 5 is used as an evaporator. The refrigerant enters the first heat exchanger 5 in the two-phase state, that is to say in the form of a liquid / gas mixture, and leaves it in the gaseous state. In other words, when the circuit operates in air conditioning mode, the refrigerant fluid is configured to transfer calories to the external air flow FAi passing through the first heat exchanger 5 and when the refrigerant circuit 3 operates in heating mode, the refrigerant fluid is configured to capture calories from the external air flow FAi which passes through the first heat exchanger 5.

In the heat treatment system 1 according to the present invention, when the refrigerant fluid circuit 3 operates in air conditioning mode, the external air flow FAi first circulates through the radiator 22 and captures the calories of the fluid. coolant circulating in the radiator 22. The external air flow FAi leaving the radiator 22, heated, is then directly brought to the first heat exchanger 5 where it captures the calories of the cooler, hotter. The refrigerant fluid circulating in the first heat exchanger 5 is then condensed.

The heat treatment system 1 according to the present invention comprises a heat exchanger 8 configured to implement a heat exchange between the refrigerant fluid circulating in the refrigerant fluid circuit 3 and the heat transfer fluid circulating in the heat transfer fluid loop 2. In particular, the heat exchanger 8 can be used as a sub-cooler or as a condenser, depending on the mode of operation envisaged. It will be understood that this heat exchanger 8 forms an interface between the refrigerant fluid circuit 3 and the heat transfer fluid loop 2 dedicated to the transfer of calories between these two fluids.

The heat exchanger 8 is arranged between the first heat exchanger 5 and the primary expansion member 61, downstream of the first heat exchanger 5. In other words, the heat exchanger 8 is interposed between the first heat exchanger 5 and the second heat exchanger 7 of the refrigerant fluid circuit 3.

Also, the heat exchanger 8 is arranged in the heat transfer fluid loop 2 so that the heat exchanger 8 is disposed upstream of the radiator 22 in the direction of flow Si of the heat transfer fluid. The refrigerant which enters the heat exchanger 8 can thus discharge its calories into the coolant, which then allows the radiator 22 to dissipate these calories in the air flow FAi outside the vehicle. Thus, the refrigerant fluid circulates in a first pass 81 of the heat exchanger 8, while the coolant circulates in a second pass 82 of this same heat exchanger 8. The coolant present in the second pass 82 is heated by heat exchange with the refrigerant fluid present in the first pass 81 of the heat exchanger 8.

Alternatively and not shown, the heat exchanger 8 is arranged downstream of the radiator 22 in the direction of circulation Si of the heat transfer fluid, so that the refrigerant entering the heat exchanger 8 is cooled beforehand by the heat transfer fluid. heat exchange carried out in the radiator 22, between the heat transfer fluid and the flow of outside air. Thus, the heat transfer fluid, cooled beforehand by heat exchange with the external air flow FAi, is brought to the second pass 82 of the heat exchanger 8 in order to perform a second heat exchange with the refrigerant fluid circulating in a first pass 81 of this same heat exchanger 8.

The arrangement according to which the heat exchanger 8 is arranged downstream of the radiator 22, according to the direction of flow Si of the heat transfer fluid, is of course transposable to any of the operating modes or alternatives illustrated in Figures 2 to 9.

It should be noted that the various fluids circulating in this heat exchanger 8 do not mix and that the exchange of heat between these two fluids takes place by conduction.

The refrigerant fluid circuit 3 as illustrated in FIG. 1 thus comprises the main branch 310 on which are successively arranged, according to the direction of circulation S2 of the refrigerant fluid, the compression device 4, the first heat exchanger 5, the heat exchanger 8, the primary expansion member 61 and the second heat exchanger 7. The refrigerant, circulating in a first portion 501 of the refrigerant circuit 2 between the compression device 4 and the primary expansion member 61 , is subjected to a high pressure, while the refrigerant fluid circulating in a second portion 502 of the circuit between the primary expansion member 61 and the compression device 4 is subjected to a low pressure, lower than the high pressure.

Advantageously, the refrigerant fluid circuit 3 of the heat treatment system 1 comprises an internal heat exchanger 31. This internal heat exchanger 31 makes it possible to recover calories from a portion of the refrigerant circuit 3, here the first portion 501, for them. exchange with another portion of this same circuit, here the second portion 502, so as to reduce the power consumed by the compression device 4 and overall increase the performance of the refrigerant circuit.

The internal heat exchanger 31 is thus placed between two pipes exhibiting a temperature differential between them. We then distinguish a first pipe 302, called high pressure and high temperature, and a second pipe 303, called low pressure and low temperature, which respectively comprise a first part 318 of the internal heat exchanger 31 in which the refrigerant circulates at high pressure and high temperature and a second part 319 in in which the refrigerant circulates at a lower pressure and a lower temperature. The low temperature refrigerant fluid being colder than the higher pressure refrigerant fluid, it is understood that the internal heat exchanger 31 allows heat exchange between its two parts 318, 319, and therefore between the two pipes 302, 303 of the circuit. 3 of refrigerant fluid on which these parts are arranged.

In the example illustrated, the first part 318 of the internal heat exchanger 31 is arranged between the heat exchanger 8 and the primary expansion member 61 and the second part 319 of this internal heat exchanger 31 is arranged between the second heat exchanger 7 and the compression device 4. The internal heat exchanger 31 allows the heating of the refrigerant fluid upstream of the compression device 4 so that this refrigerant fluid arrives in this compression device 4 in the gaseous state. In all of the figures in this document, the heat exchange implemented between the first part 318 of the internal heat exchanger 31 and the second part 319 of the internal heat exchanger is schematically represented by the dotted line 100.

The main branch 310 of the refrigerant fluid circuit 3 comprises an accumulation device 32 arranged between the second heat exchanger 7 and the second part 319 of the internal heat exchanger 31, upstream of the compression device 4. The accumulation device 32 makes it possible to accumulate a liquid phase of the refrigerant fluid so as to guarantee that only a gaseous phase of the refrigerant fluid goes towards the compression device 4. Also, the accumulation device 32 makes it possible to manage the quantity of refrigerant fluid circulating in the compression device. the refrigerant fluid circuit 3. The refrigerant fluid circuit 3 comprises a secondary branch 320 which diverges from the main branch 310 at a point of divergence, called the first point of divergence 311, located between the first part 318 of the internal heat exchanger 31 and the expansion member. primary 61 and which joins the main branch 310 at a first point of convergence 312 located between the second heat exchanger 7 and the storage device 32.

The secondary branch 320 successively comprises, according to the direction of flow S2 of the coolant, a secondary expansion member 321 and a heat exchanger secondary 322 thermally coupled to an electrical storage device 9 of the vehicle configured to supply electric power to at least one element of the electric traction chain of said vehicle. The secondary heat exchanger 322 is thus arranged in parallel with the second heat exchanger 7, from the point of view of the refrigerant fluid. It will be understood that the electrical storage device 9 is arranged near, or advantageously in thermal contact, the secondary heat exchanger 322 and that the latter is configured to implement a heat exchange between the refrigerant circulating in the secondary branch 320 and a second heat transfer fluid loop 10 comprising the electrical storage device 9 and configured to ensure cooling. The heat transfer fluid present in this second loop 10 is circulated by a circulator 110.

The refrigerant fluid circuit 3 further comprises a tertiary branch 330 which diverges from the main branch 310 at the level of the first point of divergence 311 and which joins the main branch 310 between the compression device 4 and the first heat exchanger 5, at the level a second point of convergence 313. The tertiary branch 330 makes it possible to bypass the second heat exchanger 7 and to send the refrigerant fluid leaving the heat exchanger 8 to the first heat exchanger 5. This bypass can in particular be put into operation. works when the circuit is operating in heating mode in order to send a flow of hot air into the vehicle interior.

The refrigerant fluid circuit 3 also comprises a quaternary branch 340 which diverges from the main branch 310 at a second point of divergence 314, located between the first heat exchanger 5 and the heat exchanger 8 and which joins the main branch 310 at the level of the first point of convergence 312. The quaternary branch 340 allows the second heat exchanger 7 to be bypassed, in particular when the refrigerant fluid circuit 3 operates in heating mode. Particularly, the quaternary branch 340 may comprise at least one member 12 for regulating the flow of refrigerant fluid configured to direct the refrigerant to the main branch 310 or to the quaternary branch 340. Finally, the refrigerant circuit 3 comprises a branch of branch 350 which diverges from the main branch 310 at a bifurcation point 315, between the compression device 4 and the first heat exchanger 5, and which joins the main branch 310 at a connection point 316, located between the first heat exchanger 5 and the heat exchanger 8.

The main branch 310 comprises at least a first regulator 121 of the flow of refrigerant fluid arranged between the compression device 4 and the first heat exchanger 5, while the bypass branch 350 comprises at least one second regulator 122 of the flow of refrigerant fluid arranged between the compression device 4 and the connection point 316, said regulating members 12, 121, 122 of the flow of refrigerant fluid making it possible to selectively direct the refrigerant to the main branch 310 or to the bypass branch 350 by authorizing and prohibiting the circulation of this refrigerant fluid in one or the other of these branches. In particular, said regulators 12, 121, 122 of the flow of refrigerant fluid can be two-way valves or a single three-way valve installed at the bifurcation point 315.

The bypass branch 350 associated with the regulating members 12, 121, 122 of the flow of refrigerant fluid can in particular make it possible to bypass the first heat exchanger 5, in particular when the refrigerant circuit 3 is operating in heating mode and it is necessary to '' send a flow of hot air into the vehicle interior.

The main branch 310 comprises at least one non-return valve 33 located between the first heat exchanger 5 and the connection point 316 and configured to impede the circulation of the refrigerant fluid coming from the bypass branch 350 towards the first heat exchanger 5, and allow the circulation of coolant between the second point of divergence 314 and the connection point 316. According to the example illustrated in FIG. 1, the loop 2 of heat transfer fluid comprises a main line 210 on which are successively arranged, according to the direction of flow If the heat transfer fluid, at least the circulation device 21 of the heat transfer fluid, the heat exchanger 8 and the radiator 22.

The heat transfer fluid loop 2 further comprises a bypass line 220 which diverges from the main line 210 between the circulation member 21 and the radiator 22, upstream of the circulation member, and which joins it. at a junction point 201 located between the radiator 22 and the heat exchanger 8. In in other words, the bypass line 220 bypasses the radiator 22. The heat transfer fluid loop 2 comprises in particular a three-way valve 202 in order to selectively ensure the circulation of the heat transfer fluid along the main line 210 and / or of the bypass line 220. In addition, the bypass line 220 comprises an air heater 23 configured to implement a heat exchange between the coolant and the internal air flow FA2. Additionally, the heat transfer fluid loop 2 may comprise at least one electric heating device 24 of the heat transfer fluid arranged upstream of the air heater, according to the direction of circulation Si of the heat transfer fluid.

The heat transfer fluid loop 2 finally comprises an additional line 230 which comprises at least one means 231 for circulating the heat transfer fluid in this line, such as a pump, and a heat exchanger 232 intended for the heat treatment of at least one. element of the electric traction chain of the vehicle, for example an electric motor and / or a control module for this electric motor. The additional line 230 diverges and converges from the main line 210 of the heat transfer fluid loop 2 on either side of the radiator 22 respectively, the circulation of the heat transfer fluid along the additional line 230 being, by way of example, controlled by a three-way valve 203 or, alternatively, by a plurality of means for regulating the flow rate of the heat transfer fluid, not shown.

The additional line 230 is intended for the heat treatment of the element of the electric traction chain of the vehicle, for example an electric motor and / or a control module of this electric motor, and is arranged in order, for example, to operate a heat exchange between the heat transfer fluid circulating in the additional line 230 and the flow of air FAi outside the vehicle interior. In particular, the external air flow FAi can ensure the cooling of the heat transfer fluid which can then collect via the heat exchanger 232 heat emitted by the element of the traction chain thermally.

FIG. 1 also shows a ventilation, heating and / or air conditioning installation 40 which comprises a housing 41 delimiting an internal volume. The internal air flow FA2 is channeled through this housing 41 before being sent into the passenger compartment of the vehicle. The housing accommodates the second heat exchanger 7 and the air heater 23. The ventilation, heating and / or air conditioning installation 40 also includes a fan 42 responsible for setting in motion the internal air flow FA2 in the air conditioning unit. housing 41, as well as mixing or distribution flaps generally designated by the reference 43.

FIGS. 2 to 7 represent different examples of the operation of the heat treatment system 1 as explained previously in FIG. 1. In these figures, the solid lines represent pipes of the heat treatment system 1 in which the refrigerant fluid or the fluid coolant circulate, while the dotted lines represent pipes of the heat treatment system 1 in which neither the coolant nor the coolant circulate. The external air flow FAi, the internal air flow FA2 and its direction of circulation S3, a direction of circulation Si of the heat transfer fluid in the heat transfer fluid loop 2 and a direction of circulation S2 of the refrigerant fluid in the circuit 3 refrigerant are also shown schematically in the various Figures 1 to 9. The flow regulating members or means are for their part shown full when they block the circulation of the fluid concerned, and hollowed out when they allow said circulation. FIG. 2 thus illustrates a first example of the operation of the heat treatment system 1 in which the refrigerant fluid circuit 3 is configured to operate in air conditioning mode, that is to say that it is configured to cool the flow of interior air FA2 before it is sent to the vehicle interior.

According to this first example of operation, in the refrigerant fluid circuit 3, the secondary branch 320, the tertiary branch 330 and the quaternary branch 340 are not traversed by the refrigerant fluid. For example, the circulation of the refrigerant fluid can be impeded by at least one of the expansion members 6 and / or one of the regulating members 12 of the refrigerant circuit included in the corresponding branches. The same is true for the bypass branch 350. In other words, in the present example of operation, the circulation of the refrigerant fluid is limited to the main branch 310 of the circuit 3 of the refrigerant fluid.

Thus, according to this first example of the operation of the heat treatment system 1, the refrigerant fluid leaves the compression device 4 under high pressure, at high temperature and in the gaseous state. The refrigerant fluid arrives at the bifurcation point 315 where the combination of the closing of the second regulator 122 and the opening of the first regulator 121 prevents the circulation of the refrigerant in the bypass branch 350. As a result, the refrigerant fluid circulates in the main branch 310 towards the first heat exchanger 5 which operates as a condenser.

The refrigerant thus arrives at the first heat exchanger 5 in the gaseous state and at a temperature above the temperature of the outside air flow FAi and transfers its calories to the outside air flow FAi. The refrigerant thus cooled thus leaves the first heat exchanger 5 mainly in the liquid state.

The refrigerant fluid is then brought to the level of the connection point 316 then to the heat exchanger 8. The refrigerant fluid then circulates in the first pass 81 of the heat exchanger 8, this refrigerant having a temperature greater than that of the heat transfer fluid circulating in the second pass 82 of this same heat exchanger 8. Advantageously, this temperature difference allows sub-cooling, to a temperature below its condensation temperature, of the refrigerant. The refrigerant fluid leaving the heat exchanger 8, essentially in the liquid state, is sent to the primary expansion member 61 where it undergoes a decrease in its pressure.

The refrigerant, at low pressure and in a two-phase state, reaches the second heat exchanger 7, used as an evaporator, in which it is evaporated by capturing calories from the internal air flow FA2. The internal air flow FA2 is cooled and sent to the passenger compartment of the vehicle while the refrigerant fluid leaves the second heat exchanger 7. The refrigerant fluid then joins the accumulation device 32 in which, as described above, the phase liquid and the gas phase are separated so that only the gas phase is then sent to the second part 319 of the internal heat exchanger 31 and then, again, to the compression device 4.

In the heat transfer fluid loop 2, the bypass line 220 is not traversed and the circulation of the heat transfer fluid takes place essentially at the level of the main line 210 and the additional line 230.

Within the heat transfer fluid loop 2, the heat transfer fluid which circulates in the heat exchanger 8 is, at least in part, reheated by the heat exchange carried out with the refrigerant fluid. The heat transfer fluid circulates along the main line 210 by setting in motion via the circulation member 21, then passes through the radiator 22 where it is cooled by heat exchange with the air flow. exterior FAi, operated in the radiator 22. This results in cooling of the refrigerant fluid present in the heat exchanger 8, this refrigerant fluid having been condensed beforehand during its passage through the first heat exchanger 5. The refrigerant fluid which passes through the first pass 81 is in the liquid state and undergoes cooling to a temperature close to that of the outside air flow FAi. It should be noted here that the radiator 22 is crossed first by this flow of outside air FAi, so that the temperature of the heat transfer fluid is lowered to the lowest temperature available on the front face of the vehicle. This is how it is possible to perform efficient sub-cooling of the refrigerant fluid present in the heat exchanger 8.

FIG. 3 illustrates a second example of operation of the heat treatment system 1. This second example of operation is substantially similar to that described above in that it relates to an air conditioning mode of the refrigerant circuit 3 and the description given of these elements. with reference to FIG. 2 can be transposed to this second example of operation illustrated in FIG. 3. This second example of operation nevertheless differs from the first example of operation in particular in that the secondary branch 320 of the refrigerant circuit 3 is traversed, otherwise said the secondary expansion member 321 allows the circulation of the refrigerant fluid in said secondary branch 320. It follows that the refrigerant circuit 3 here simultaneously allows cooling of the passenger compartment and cooling of the electrical storage device 9, directly or via the second loop 10.

Indeed, when the refrigerant fluid arrives at the first point of divergence point 311, part of the refrigerant fluid is directed towards the primary expansion member 61 and towards the second heat exchanger 7, as described with reference to FIG. 2 , and another part of this refrigerant fluid is directed towards the secondary expansion member 321 of the secondary branch 320 in which it undergoes an expansion before joining the secondary heat exchanger 322.

In the secondary heat exchanger 322, the refrigerant fluid, circulating in a first pass 3221 of the secondary heat exchanger 322, captures calories from the heat transfer fluid circulating in a second pass 3222 of this secondary heat exchanger 322. The refrigerant fluid leaves l 'secondary heat exchanger 322 in predominantly gaseous form and reaches the first point of convergence 312 in order to be directed towards the storage device 32. At the same time, the coolant which has been cooled in the secondary heat exchanger 322 circulates in the second loop 10 of coolant 2 so as to cool the device. electrical storage 9. FIG. 4 schematically represents a third example of the operation of the heat treatment system 1 according to which the refrigerant circuit 3 operates in passenger compartment heating mode, that is to say it warms up the interior air flow FA2 before it is sent into the vehicle cabin. In this third example of operation, the secondary branch 320 of the refrigerant fluid circuit 3, thermally coupled to the electrical storage device 9, is not traversed. Also, in the present example of operation, the radiator 22 is inactive, in the sense that it is not crossed by the heat transfer fluid.

The refrigerant fluid leaves the compression device 4 in the gaseous state, at high pressure and at high temperature, and goes towards the bifurcation point 315. The first regulator 121, included in the main branch 310, is closed while that the second regulator 122, included in the bypass branch 350, is open. The compressed refrigerant fluid is thus diverted from the main branch 310 and sent to the bypass branch 350 so as to bypass the first heat exchanger 5.

The compressed refrigerant passes through connection point 316 and then enters heat exchanger 8, which in the present world of operation is used as a condenser. The refrigerant fluid circulating in the first pass 81 of the heat exchanger 8 transfers calories to the cooler heat transfer fluid which circulates in the second pass 82 of the heat exchanger 8. The refrigerant then leaves the heat exchanger. heat 8 in an at least partially liquid state and enters the first part 318 of the internal heat exchanger 31.

When the refrigerant fluid circuit 3 operates according to the heating mode, the operation of the internal heat exchanger 31 remains similar to that previously explained, that is to say that the refrigerant fluid circulating in the first part 318 of the exchanger internal thermal 31 heats the refrigerant circulating in the second part 319 of the internal heat exchanger 31, disposed upstream of the compression device 4. The refrigerant fluid leaving the first part 318 of the internal heat exchanger 31 is thus advantageously cooled and then directed towards the first point of divergence 311.

At this level, the primary expansion member 61 and the secondary expansion member 321 respectively impede the circulation of the refrigerant fluid to the second heat exchanger 7 and the secondary branch 320. The refrigerant fluid is therefore directed to the tertiary branch 330. The refrigerant fluid passes through a tertiary expansion member 331, in which it undergoes an expansion, and emerges in the two-phase state. The expanded refrigerant then passes through the second point of convergence 313 and then enters the first heat exchanger 5, used as an evaporator, which is configured to implement a heat exchange between this refrigerant and the outside air flow FAi at l interior.

By way of example, the refrigerant fluid entering the first heat exchanger 5 may have a temperature of the order of -30 ° C while the outside air flow FAi has a higher temperature, for example of the order of -20 to -5 ° C. In particular, the radiator 22 being stopped when the refrigerant fluid circuit 3 is operating in heating mode, the external air flow FAi first passes through the radiator 22 without its temperature being changed.

Then, the external air flow FAi passes through the first heat exchanger 5 and transfers its calories to the cooler refrigerant fluid circulating in the first heat exchanger 5 so as to evaporate it. The refrigerant fluid leaving the first heat exchanger 5 circulates up to the level of the second point of divergence 314 of the refrigerant fluid circuit 3, at which level it is sent to the quaternary branch 340. A connecting pipe 305 of the main branch 310, connecting the second point of divergence 314 and the connection point 316, is not traversed by the refrigerant fluid, the circulation of the refrigerant fluid in the connection pipe 305 being prohibited by the pressure difference between the high pressure portion and the low pressure portion of the refrigerant circuit 3.

The refrigerant fluid is thus brought to the first point of convergence 312 then circulates in the main branch 310, successively through the storage device 32 and the second part 319 of the internal heat exchanger 31, before being returned to the compression device 4. Thus, in the present mode of operation, the refrigerant fluid bypasses the second heat exchanger 7 and does not travel through the secondary branch 320, so that the second heat exchanger 7 and the secondary heat exchanger 322 remain inactive.

As previously explained, when the refrigerant fluid circuit 3 operates in heating mode, the radiator 22 is inactive and the heat transfer fluid circulating in the heat transfer fluid loop 2 bypasses it. The heat transfer fluid is thus circulated by the circulation member 21 then, passes through the heat exchanger 8, bypasses the radiator 22 thanks to the fact that the three-way valve 202 is placed in a position allowing the circulation of fluid. coolant in the bypass line 220.

According to the example of FIG. 4, the heat transfer fluid does not pass through the additional line 230 of the heat transfer fluid loop 2 for the purpose of cooling at least the heat exchanger 232 of the electric drive train of the vehicle. Alternatively, the cooling of the heat exchanger 232 dedicated to the element of the electric traction chain can be ensured by operating the pump 231 so as to collect calories from the heat exchanger 232 and then to discharge them into the outside air flow FAi.

The heat transfer fluid heated by heat exchange within the heat exchanger 8 is sent to the air heater 23 by operating the circulation member 21, the air heater 23 being configured to implement a heat exchange between the heat transfer fluid and the internal air flow FA2. The internal air flow FA2 having a temperature lower than that of the heat transfer fluid circulating in the heater 23, it captures the calories of this heat transfer fluid. The internal air flow FA2 thus heated can then be sent to the vehicle interior.

The heat transfer fluid circulates in the bypass line 220 then is brought to the heat exchanger 8 which functions as a condenser of the refrigerant fluid. As previously explained, the heat transfer fluid circulating in the second pass 82 of the heat exchanger 8 captures the calories of the refrigerant fluid circulating in the first pass 81 of said heat exchanger 8. The heated outgoing heat transfer fluid is then sent to a device. flow control valve 12. In this operating mode, the electric heating device 24 can be activated so as to provide heat to the coolant, before it enters the air heater 23. This makes it possible to provide additional heating to the passenger compartment, depending on the condition. demand. FIG. 5 represents a fourth example of the operation of the heat treatment system 1 of the present invention in which the refrigerant fluid circuit 3 operates in heating and heat recovery mode, in particular those of the electrical storage device 9.

This fourth example of operation differs from the third example of operation in that the secondary branch 320 of the refrigerant fluid circuit 3 is traversed by the refrigerant. The secondary expansion member 321 is open and configured to reduce the pressure of the refrigerant fluid upstream of the secondary heat exchanger 322. As previously explained, the refrigerant fluid circulates in the first pass 3221 of the heat exchanger. secondary 322 which functions as an evaporator with respect to the refrigerant fluid. A temperature of this refrigerant fluid being lower than a temperature of the heat transfer fluid which circulates in the second pass 3222 of the secondary heat exchanger 322, the refrigerant fluid captures the calories of the heat transfer fluid circulating in the second loop 10, said heat transfer fluid then ensuring cooling the electrical storage device 9 of the vehicle. Advantageously, the calories transferred by the electrical storage device 9 to the coolant of the second loop 10 are recovered and make it possible to heat the coolant of the coolant circuit 3 upstream of the compression device 4. The coolant thus leaves the secondary heat exchanger 322 in the gaseous state and then joins the first point of convergence 312, then the accumulation device 32 on the main branch 310.

As regards the rest of the refrigerant fluid circuit 3 and the heat transfer fluid loop 2, this operating example is identical to the third operating example described with reference to FIG. 4. FIG. 6 is a diagrammatic illustration of a fifth operating example. of the heat treatment system 1 in which the refrigerant fluid circuit 3 operates in heating and dehumidification mode. This fifth mode of operation can in particular be implemented when the temperature of the external air flow FAi is of the order of o to io ° C for example, that is to say when it may be necessary to send hot air in the passenger compartment of the vehicle but also to dehumidify the air circulating in said passenger compartment in order to prevent the accumulation of mist on the various glazed surfaces delimiting it, which could impede the visibility of the driver of said vehicle.

This fifth example of operation is substantially similar to the third example of operation, described previously with reference to FIG. 4. It nevertheless differs from the third example of operation in that, at the level of the first point of divergence 311, the refrigerant fluid separates into two parts, part of which is sent to the tertiary branch 330 while the other part continues to circulate on the main branch 310.

The primary expansion member 61 is thus open and configured to operate an expansion of the refrigerant fluid. The expanded refrigerant then joins the second heat exchanger 7 in which it transfers calories to the internal air flow FA2. In the present example of operation, the second heat exchanger 7 operates as a second evaporator, in addition to the first heat exchanger 5 which can then be qualified as the first evaporator. The FA2 interior airflow cooling allows the FA2 interior airflow to be dried before it is discharged into the vehicle cabin, thus preventing fogging of the glass surfaces of the cabin. As illustrated, the refrigerant fluid which leaves the second heat exchanger 7 and the refrigerant fluid which circulates in the quaternary branch 340, that is to say the refrigerant fluid leaving the first heat exchanger 5, meet at the level of the first point of convergence 312 before being brought to the accumulation device 32.

FIG. 7 illustrates a sixth example of the operation of the heat treatment system 1 in which the refrigerant fluid circuit 3 is in heating and dehumidification mode. This sixth example of operation can in particular be implemented when the external air flow FAi has a temperature of the order of 10 to 20 ° C, that is to say when it may be necessary to ensure a low heating of the interior air flow FA2, sent to the passenger compartment, and that dehumidification of the air present in the passenger compartment must be ensured in order to prevent the accumulation of mist on the various glass surfaces. The sixth example of operation differs from the fifth example of operation in that the first heat exchanger 5 is not operated and in that the tertiary branch 330 and the quaternary branch 340 of the refrigerant circuit 3 are not traversed by the fluid. refrigerant. In other words, the second heat exchanger 7 on its own makes it possible to evaporate a sufficient quantity of refrigerant fluid for the thermodynamic cycle of the refrigerant fluid circuit 3 to take place. Thus, in the present mode of operation, the compressed and gaseous refrigerant fluid leaving the compression device 4 is sent, at the level of the bifurcation point 315, to the bypass branch 350 so as to bypass the first heat exchanger 5. Such as previously explained, such a bypass can be implemented by closing the first regulating member 121 and opening the second regulating member 122, respectively included on the main branch 310 and the bypass branch 350.

The refrigerant then passes at the connection point 316 and is brought to the heat exchanger 8, the non-return valve 33, disposed on the connection pipe 305 of the main branch 310, preventing the return of the refrigerant to the first heat exchanger 5. The heat exchanger 8 is then used as a condenser so that the refrigerant circulating in the first pass 81 of this heat exchanger 8 transfers its calories to the heat transfer fluid circulating in the second pass 82 of said exchanger of heat 8. The refrigerant fluid leaves the heat exchanger 8 at least partly condensed and is sent to the first part 318 of the internal heat exchanger 31 and then to the primary expansion member 61, in which it is expanded. .

The expanded refrigerant then enters the second heat exchanger 7 which, as described with reference to the fifth example of operation and to FIG. 6, operates as an evaporator so as to ensure the cooling, and therefore the drying, of the flow of interior air FA2 before it is sent to the vehicle cabin. The refrigerant then leaves the second heat exchanger 7 in the gaseous state and rejoins the storage device 32. The rest of this refrigerant fluid circuit 3 and of the heat transfer fluid loop 2, for their part, operate in a similar way to the fifth. example of operation illustrated in figure 6.

In the heat treatment system 1 exposed above, the refrigerant circuit 3 is configured so that the refrigerant circulates in the same direction at the level of the first heat exchanger 5 when it is operating in air conditioning mode or in heating mode. In other words, in the operating examples illustrated in Figures 2 and 3, for which the refrigerant circuit 3 operates in air conditioning mode and the first heat exchanger 5 is used as a condenser, the refrigerant enters the first heat exchanger 5 to l 'essentially gaseous state at a first end 51 of the first heat exchanger 5 and emerges in the liquid state at a second end 52. In the operating examples illustrated in Figures 4 to

7, for which the refrigerant fluid circuit 3 operates in heating mode and the first heat exchanger can be used as an evaporator, the refrigerant fluid enters the first heat exchanger 5 in the two-phase state at this same first end 51 of the first heat exchanger 5 and emerges from it in the predominantly gaseous state at the second end 52.

FIG. 8 schematically illustrates an alternative architecture of the treatment system in which the refrigerant fluid circulates in opposite directions of flow depending on whether the refrigerant fluid circuit 3 operates in air conditioning mode or in heating mode. Such an architecture makes it possible to optimize the efficiency of the heat exchanges taking place within the first heat exchanger 5. It is understood that the elements common to these two embodiments bear the same references. Also, the description of the various operating examples made with reference to the heat treatment system 1 illustrated in FIG. 1 can be transposed to the alternative embodiment as illustrated in FIG.

8.

The refrigerant circuit 3 illustrated in FIG. 8 differs from those represented in FIGS. 1 to 7 in that the tertiary branch 330 branches off the refrigerant fluid from the main branch 310 between the heat exchanger 8 and the control unit. primary expansion 61 and brings it to the main branch 310, between the first heat exchanger 5 and the heat exchanger 8.

In FIG. 8, the tertiary branch 330 branches off from the main branch 310 at the level of the first point of divergence 311. On the other hand, the position of the second point of convergence 313, connecting the tertiary branch 330 to the main branch 310, is modified. As previously described with reference to Figures 1 to 7, the branch tertiary 330 comprises at least the tertiary expansion member 331.

Also, the refrigerant fluid circuit 3 according to the present alternative differs from those previously exposed in that the quaternary branch 340 branches off from the main branch 310 at the level of the second point of divergence 314, included between the first heat exchanger 5 and the device. compression 4, and joins said main branch 310 at the first point of convergence 312.

In other words, the second point of convergence 313 and the second point of divergence 314, respectively connecting the tertiary branch 330 and the quaternary branch 340 to the main branch 310, have, in particular with respect to the first heat exchanger 5, positions inverses of what has been previously described with reference to Figures 1 to 7.

When the refrigerant fluid circuit 3 according to the present alternative uses the air conditioning mode, the flow of the refrigerant fluid in the refrigerant fluid circuit 3, limited to the main branch 310, or even also to the secondary branch 320, is identical to this. which has been previously described, in particular with reference to FIGS. 2 and 3. The refrigerant thus enters the first heat exchanger 5, used as a condenser, in the gaseous state at the level of the first end 51 of the first heat exchanger 5 and in emerges in the essentially liquid state at the second end 52.

FIG. 9 illustrates an example of the operation of the heat treatment system 1 according to which the refrigerant fluid circuit 3 operates as a heat pump, similar to the operating mode previously exposed in FIG. 4. The description given of the fluid circuit 3 refrigerant and of the heat transfer fluid loop 2 thus applies to the present alternative, the latter differing in that, when the refrigerant arrives in the liquid state at the level of the first point of divergence 311, the part of the refrigerant fluid sent to the tertiary branch 330 is brought by the tertiary branch 330 to the second end 52 of the first heat exchanger 5, configured to be used as an evaporator, instead of the first end 51 of the first heat exchanger as has been explained for figures 1 to 7.

As previously explained, the refrigerant fluid is evaporated by heat exchange with the external air flow FAi. Then, it comes out at least partly gaseous at the first end 51 of the first heat exchanger 5, passes the second point of divergence 314 then circulates along the quaternary branch 340 to the first point of convergence 312 in order to be brought to the storage device 32 The rest of the refrigerant fluid circuit 3, the path of the latter, as well as the refrigerant fluid loop remain identical to what has been previously explained, in particular in the third example of operation, with reference to FIG. 3.

The present invention thus proposes a heat treatment system in which a radiator of a heat transfer fluid loop is arranged on the front face of the vehicle, upstream, according to the direction of circulation of an external air flow, of an exchanger. thermal of a refrigerant circuit 3. The heat treatment system according to the invention also comprises a heat exchanger configured to perform a heat exchange between the refrigerant fluid and the heat transfer fluid so as to ensure the sub-cooling of the refrigerant fluid, in particular when the circuit operates in the air conditioning mode. in order to improve the coefficient of performance of the system as a whole.

The present invention should not, however, be limited to the means and configurations described and illustrated here and it also extends to all equivalent means and configurations and to any technically operative combination of such means. In particular, the architecture of the heat transfer fluid circulation loop and the architecture of the refrigerant fluid circuit can be modified without harming the invention insofar as they make it possible to fulfill the functionalities of the heat treatment system described and illustrated. in this document.

Claims

1. Heat treatment system (1) for a vehicle comprising at least one refrigerant circuit (3) and at least one loop (2) of coolant, the circuit (3) of refrigerant comprising at least a first exchanger heat exchanger (5) and a second heat exchanger (7), the first heat exchanger (5) being configured to implement a heat exchange between the coolant and a flow of air outside (FAi) to the vehicle interior and the second heat exchanger (7) being configured to implement a heat exchange between the refrigerant fluid and an interior air flow (FA2) intended to be sent into the passenger compartment, the heat transfer fluid loop (2) comprising at the at least one radiator (22) configured to implement a heat exchange between the external air flow (FAi) and the heat transfer fluid, the heat treatment system (1) comprising at least one heat exchanger (8) configured for implement an exchange of heat between the refrigerant fluid circulating in the circuit (3) and the heat transfer fluid circulating in the loop (2), characterized in that the heat exchanger (8) is arranged on the refrigerant circuit (3) between the first heat exchanger (5) and the second heat exchanger (7), the heat exchanger (8) and the radiator (22) being arranged in the heat transfer fluid loop (2) so that the radiator (22) discharges in the flow of outside air (FAi) of the calories captured by the heat exchanger (8).

2. Heat treatment system (1) according to the preceding claim, wherein the heat exchanger (8) is arranged in the loop (2) of heat transfer fluid downstream of the radiator (22), according to the direction of flow of the fluid. heat transfer fluid in the heat transfer fluid loop (2).

3. Heat treatment system (1) according to claim 1, wherein the heat exchanger (8) is arranged in the loop (2) of heat transfer fluid upstream of the radiator (22), according to the direction of flow of the fluid. heat transfer fluid in the heat transfer fluid loop (2).

4. Heat treatment system (1) according to any one of claims previous ones, in which the circuit (3) of refrigerant fluid is a closed circuit which comprises at least one main branch (310) on which are arranged at least one compression device (4), the first heat exchanger (5), the second heat exchanger (7) and at least one expansion member (6), said primary expansion member (61), arranged between the heat exchanger (8) and the second heat exchanger (7), the radiator (22) being arranged upstream of the first heat exchanger (5) in the direction of circulation (S3) of the flow of outside air (FAi).

5. Heat treatment system (1) according to the preceding claim, wherein the refrigerant circuit (3) comprises a secondary branch (320) which extends between a first point of divergence (311), between the exchanger heat exchanger (8) and the second heat exchanger (7), and a first point of convergence (312), between the second heat exchanger (7) and the compression device (4), the secondary branch (320) comprising at minus a secondary expansion member (321) and a secondary heat exchanger (322) thermally coupled to an electrical storage device (9) of the vehicle.

6. Heat treatment system (1) according to claim 5, wherein the refrigerant circuit (3) comprises a tertiary branch (330) which branches off the refrigerant from the main branch (310) between the heat exchanger ( 8) and the primary expansion member (61) and brings it to the main branch (310) at a second point of convergence (313) located downstream of the compression device (4), between the compression device (4) ) and the first heat exchanger (5), the tertiary branch (330) comprising at least one tertiary expansion member (331).

7. Heat treatment system (1) according to claim 5, wherein the refrigerant circuit (3) comprises a tertiary branch (330) which branches off the refrigerant fluid from the main branch (310) between the heat exchanger ( 8) and the primary expansion member (61) and brings it to the main branch (310) at a second point of convergence (313) located downstream of the first heat exchanger (5), between this first heat exchanger (5) ) and the heat exchanger (8), the tertiary branch (330) comprising at least one tertiary expansion member (331).

8. Heat treatment system (1) according to any one of claims 4 to 7, wherein the circuit (3) of refrigerant fluid comprises a bypass branch (350) which diverges from the main branch (310) downstream of the. device compression (4), between this compression device (4) and the first heat exchanger (5), the bypass branch (350) having a connection point (316) with said main branch (310) located between the first heat exchanger (5) and the heat exchanger (8), downstream of the first heat exchanger (5) and of a non-return valve (33).

9. Heat treatment system (1) according to the preceding claim, wherein the main branch (310) and / or the bypass branch (350) comprise at least one regulating member (12) of the flow of refrigerant arranged between the compression device (4) and the first heat exchanger (5).

10. Heat treatment system (1) according to any one of the preceding claims, wherein the loop (2) of heat transfer fluid is a closed loop which comprises at least one main line (210), on which are at least arranged the radiator (22), the heat exchanger (8) and a circulating member (21) of the coolant, and at least one bypass line (220) which diverges from the main line (210) between the member circulation (21) of the heat transfer fluid and the radiator (22), the bypass line (220) having a junction point (201) with said main line (210) arranged between the radiator (22) and the exchanger heat (8).

11. Heat treatment system (1) according to any one of the preceding claims, wherein the loop (2) of heat transfer fluid comprises at least one additional line (230) for circulation of the heat transfer fluid which comprises at least one dedicated heat exchanger. the heat treatment of at least one element (232) of the electric traction chain of the motor vehicle.