FR3051546A1 - AGENCY REFRIGERANT FLUID CIRCUIT FOR THERMALLY CONTROLLING AN ENERGY SOURCE - Google Patents

Abstract

The invention relates to a refrigerant circuit (19) inside which a refrigerant fluid is able to circulate, the refrigerant circuit (1) comprising at least a first heat exchanger (6) and at least a second heat exchanger heat exchanger (9), characterized in that the refrigerant circuit (1) comprises a first branch (13) provided with a first expansion device (2), the first branch (13) having a branch point (16). ) common to a second leg (14) and to a third leg (15), the second leg (14) being provided with a second expansion device (3) and the first heat exchanger (6), the second device detent (3) being interposed between the branch point (16) and the first heat exchanger (6), the third branch (15) being provided with the second heat exchanger (9) and a first expansion member (12). ), the second heat exchanger (9) being interposed between the diversion point (16) and the first expansion member (12).

Description

Refrigerant circuit arranged to thermally control a source of energy.

The field of the present invention is that of refrigerant circuits for a heating, ventilation and / or air conditioning system, especially for a passenger compartment of a motor vehicle. It relates to a refrigerant circuit which comprises a first heat exchanger and which is associated with a heat transfer liquid circuit via a second heat exchanger.

A motor vehicle is commonly equipped with a refrigerant circuit for modifying a temperature of an air contained inside a passenger compartment of the motor vehicle. The document US 2015/0121939 discloses a refrigerant circuit of the aforementioned type including in particular an accumulator downstream of two parallel circuit portions, a first portion comprising a first valve, a first expansion device and a first heat exchanger and a second portion comprising a second valve, a second expansion device and a second heat exchanger. In an operating mode where the first valve and the second valve are simultaneously open, the mass flow rate management inside the first portion and the second portion is random, which is unsatisfactory.

Indeed, it is desirable to be able to control the pressure, independently, of the refrigerant in the first heat exchanger and in the second heat exchanger, which does not allow the refrigerant circuit of US 2015/0121939.

An object of the present invention is to provide a refrigerant circuit which offers a satisfactory solution to the problem referred to above.

An object of the present invention is a refrigerant circuit inside which a refrigerant circulates, the refrigerant circuit comprising at least a first heat exchanger arranged to heat-treat a first air flow and at least a second heat exchanger arranged to exchange calories with a coolant circulating inside a coolant circuit comprising a source of energy.

According to the present invention, the refrigerant circuit inside which a refrigerant fluid is able to circulate comprises at least a first heat exchanger and at least a second heat exchanger, characterized in that the refrigerant circuit comprises a first branch provided with a first expansion device, the first branch having a common branch point to a second branch and a third branch, the second branch being provided with a second expansion device and the first heat exchanger, the second expansion device being interposed between the branch point and the first heat exchanger, the third branch being provided with the second heat exchanger and a first expansion member, the second heat exchanger being interposed between the bypass point and the first relaxing organ.

The refrigerant circuit advantageously comprises at least one of the following characteristics taken alone or in combination: the second expansion device comprises a second constant-section expansion device; - The second expansion device comprises a first control valve of a refrigerant circulation in the second branch interposed between the bypass point and the second expansion member. Such a first control valve is for example a sealing valve, especially a proportional valve or all or nothing; - The first expansion member is a refrigerant flow rate control valve; the refrigerant circuit is advantageously provided with an accumulator; the accumulator is interposed between the first heat exchanger and a connection point common to the second branch and the third branch; alternatively, the accumulator is disposed downstream of a connection point common to the second branch and to the third branch, in a direction of circulation of the refrigerant fluid in the refrigerant circuit; the first heat exchanger is arranged to thermally treat a first air flow and in that the second heat exchanger is arranged to exchange calories with a heat transfer liquid circulating inside a heat transfer liquid circuit comprising a energy source ; - The third branch is provided with a first pass of the second heat exchanger. The invention also relates to a thermodynamic circuit in which circulates a refrigerant fluid. Such a thermodynamic circuit includes the refrigerant circuit detailed herein.

The thermodynamic circuit advantageously comprises at least one of the following characteristics taken alone or in combination: a first circulation line successively comprises a compressor, a first junction point, a second control valve, a second junction point, the third heat exchanger, a third junction point, a first non-return valve, a fourth junction point, a first passage of a fourth heat exchanger, a fifth junction point, a second check valve, a sixth point of junction, the first branch, the branch point, the second branch, a joint point common to the second branch and the third branch, a third control valve, a seventh connection point and the second passage of the fourth heat exchanger to return to the compressor; a second refrigerant circulation line which extends between the first junction point and the sixth junction point, the second circulation line comprising, successively from the first junction point towards the sixth junction point, a fifth exchanger heat and a fourth control valve; a third refrigerant circulation line which extends between the second junction point and the seventh junction point and which comprises a fifth control valve; a fourth circulation line which extends between the connection point and the fifth junction point and which comprises a third non-return valve; a fifth circulation line which extends between the third junction point and the fourth junction point and which comprises a third expansion member. The invention also aims to cover a formed assembly of the thermodynamic circuit detailed in this document and a heat transfer liquid circuit. wherein the heat transfer liquid circuit comprises a first pipe comprising a pump, a second heat exchanger of the second heat exchanger and a three-way valve which distributes the heat transfer liquid, either to a second pipe or to a third pipe, the second pipe being a bypass of the third pipe, the third pipe being arranged to exchange calories with the energy source. The invention also relates to a method of implementing such an assembly, wherein the compressor is operated to carry the refrigerant at a high pressure.

The method comprises is advantageously implemented according to a plurality of operating modes of which: a first mode, in which the first expansion device allows expansion, the first expansion member is closed, the first control valve is open, the first second control valve is open, the third control valve is open, the fourth control valve is closed, the fifth control valve is closed, the first non-return valve is open, the second non-return valve is open, the Third check valve is closed and the pump is stopped. a second mode, in which the first expansion device allows expansion, the first expansion element is open, the first control valve is open, the second control valve is open, the third control valve is open, the fourth control valve is closed, the fifth control valve is closed, the first non-return valve is open, the second non-return valve is open, the third non-return valve is closed and the pump is in operation. a third mode, in which the first expansion device allows expansion, the first expansion element is closed, the first control valve is open, the second control valve is open, the third control valve is open, the fourth control valve is open, the fifth control valve is closed, the first non-return valve is open, the second non-return valve is open, the third non-return valve is closed and the pump is stopped. a fourth mode, in which the first expansion device allows expansion, the first expansion member is closed, the first control valve is open, the second control valve is closed, the third control valve is closed, the fourth control valve is open, the fifth control valve is open, the first non-return valve is closed, the second non-return valve is closed, the third non-return valve is open and the pump is stopped. a fifth mode, in which the first expansion device allows expansion, the first expansion device is open, the first control valve is open, the second control valve is closed, the third control valve is closed, the fourth control valve is open, the fifth control valve is open, the first non-return valve is closed, the second non-return valve is closed, the third non-return valve is open and the pump is in operation. a sixth mode, in which the first expansion device allows expansion, the first expansion device is open, the first control valve is closed, the second control valve is closed, the third control valve is open, the fourth control valve is open, the fifth control valve is closed, the first non-return valve is closed, the second non-return valve is closed, the third non-return valve is closed and the pump is in operation. a seventh mode, in which the first expansion device allows expansion, the first expansion device is open, the first control valve is closed, the second control valve is open, the third control valve is open, the fourth control valve is open, the fifth control valve is closed, the first non-return valve is open, the second non-return valve is open, the third non-return valve is closed and the pump is in operation. an eighth mode, in which the first expansion device allows expansion, the first expansion element is open, the first control valve is closed, the second control valve is closed, the third control valve is closed, the fourth control valve is open, the fifth control valve is open, the first non-return valve is closed, the second non-return valve is closed, the third non-return valve is open and the pump is in operation. Other characteristics, details and advantages of the invention will emerge more clearly on reading the description given below as an indication in relation to drawings in which:

Fig. 1 is a schematic illustration of a refrigerant circuit of the present invention.

FIG. 2 is a schematic illustration of an alternative embodiment of the refrigerant circuit illustrated in FIG.

Figure 3 is a schematic illustration of a thermodynamic circuit comprising the refrigerant circuit shown in Figure 1 associated with a coolant circuit.

Figure 4 is a schematic illustration of a thermodynamic circuit including the refrigerant circuit shown in Figure 2 also associated with a coolant circuit.

Figure 5 is a schematic illustration of the thermodynamic circuit shown in Figure 3 shown in a first mode of operation, said air conditioning mode.

Figure 6 is a schematic illustration of the thermodynamic circuit shown in Figure 3 shown in a second mode of operation, said air conditioning mode and cooling of the power source.

Figure 7 is a schematic illustration of the thermodynamic circuit shown in Figure 3 shown in a third mode of operation, said air conditioning mode and defogging windows.

Figure 8 is a schematic illustration of the thermodynamic circuit shown in Figure 3 shown in a fourth mode of operation, said heat pump mode.

Figure 9 is a schematic illustration of the thermodynamic circuit shown in Figure 3 shown in a fifth mode of operation, said heat pump mode and heating of the energy source.

Figure 10 is a schematic illustration of the thermodynamic circuit shown in Figure 3 shown in a sixth mode of operation, said heat pump mode and cooling of the energy source.

Figure 11 is a schematic illustration of the thermodynamic circuit shown in Figure 3 shown in a seventh mode of operation, said cooling of the energy source.

Figure 12 is a schematic illustration of the thermodynamic circuit illustrated in Figure 3 shown in an eighth mode of operation, said heating of the energy source.

FIG. 13 is a Mollier diagram illustrating a thermal behavior of the thermodynamic circuit illustrated in FIG. 3 used according to the second mode of operation as represented in FIG. 6.

A motor vehicle is commonly equipped with a thermodynamic circuit for modifying a temperature of an air contained inside a cabin of the motor vehicle.

According to the present invention, the thermodynamic circuit comprises a refrigerant circuit 1 such as those shown by way of example in FIGS. 1 and 2.

The thermodynamic circuit is a closed circuit inside which a refrigerant circulates. The cooling fluid is for example a supercritical fluid such as carbon dioxide referenced R-744. The refrigerant fluid is for example still a subcritical fluid such as a fluorinated refrigerant referenced R-134a, or non-fluorinated referenced 1234yf. Such a fluid can circulate in the refrigerant circuit 1 illustrated in FIGS. 1 and 2.

In its generality, the refrigerant circuit 1 is able to allow and / or prohibit a circulation of the refrigerant inside at least one branch that the refrigerant circuit 1 comprises. The refrigerant circuit 1 is also able to allow at least one expansion, preferably two detents, of the refrigerant fluid inside the refrigerant circuit 1, the two detents being successive to one another, it is in series, inside the refrigerant circuit 1.

The refrigerant circuit 1 is also able to allow a heat exchange between the refrigerant and at least one air flow passing through a heat exchanger prior to its delivery to the interior of the passenger compartment of the motor vehicle. The refrigerant circuit 1 is also capable of allowing an exchange of heat between the refrigerant and a coolant circulating inside a heat transfer liquid circuit arranged to change a temperature of at least one energy source. The refrigerant circuit 1 is also able to regulate a pressure of the coolant distinctly inside heat exchangers that the refrigerant circuit 1 comprises.

To do this and as visible in Figures 1 and 2, the refrigerant circuit 1 comprises at least a first expansion device 2 to undergo a first pressure drop refrigerant. The first expansion device 2 is preferably an expansion device with a pressure control loop. By way of example, the first expansion device 2 is a variable section orifice, an electronic expansion valve or the like.

The eireuit refrigerant 1 comprises at least a second expansion device 3 to cause a second pressure drop to the refrigerant. The second expansion device 3 is preferably an expansion device without a pressure control loop. By way of example, the second expansion device 3 optionally comprises a first control valve 101 which is able to allow or prohibit a circulation of the refrigerant fluid through it and a second expansion device 5 without a control loop. , such as a constant section expansion member, otherwise called a fixed section capillary orifice or the like. The second expansion member 5 is configured to achieve a constant and predetermined pressure drop.

The refrigerant circuit 1 also comprises at least a first heat exchanger 6 which is arranged to allow a first heat exchange between the refrigerant and a first air stream 7. The first air flow 7 is preferably a flow of air circulating inside a housing of a heating, ventilation and / or air conditioning installation 8 to be delivered inside the passenger compartment of the motor vehicle, with a view to modifying the temperature of the air contained inside the passenger compartment of the motor vehicle.

The refrigerant circuit 1 also comprises at least a second heat exchanger 9 which is arranged to allow a second exchange of heat between the refrigerant and a coolant liquid. The second heat exchanger 9 comprises for example a first pass 10 inside which circulates the coolant and a second pass 11 within which the coolant liquid flows, the first pass 10 and the second pass 11 being arranged between them to promote an exchange of calories between the coolant and the coolant.

The refrigerant circuit 1 finally comprises at least a first expansion member 12 which is able to control an expansion and / or a flow rate of refrigerant fluid passing through the second heat exchanger 9 and which is also adapted to adapt the pressure of the refrigerant fluid. at the outlet of the second heat exchanger 9, as a function of the pressure of the refrigerant at the inlet of the first heat exchanger 6, as described below. The first expansion member 12 is also able to control a heat exchange between the first pass 10 and the second pass 11 and consecutively a temperature of the heat transfer fluid circulating inside the second pass IL

The components of the refrigerant circuit 1 are arranged relative to each other in a particular arrangement within the refrigerant circuit. More particularly, the refrigerant circuit 1 comprises a first branch 13 on which is disposed the first expansion device 2. The first branch 13 is subdivided into a second branch 14 and a third branch 15. The second branch 14 comprises the second device 3 and the first heat exchanger 6, the second expansion member 5 being interposed between the first control valve 101 and the first heat exchanger 6. The third branch 15 comprises the second heat exchanger 9 and the first 12. Still more particularly, the refrigerant circuit 1 comprises a branch point 16 where the first branch 13 splits into the second branch 14 and the third branch 15, and a connection point 17 where the second branch meet 14 and the third branch 15. From the diversion point 16 to the connection point 17, the second branch 14 comprises successively the first control valve 101, the second expansion member 5 and the first heat exchanger 6. From the branch point 16 to the connection point 17, the third branch 15 comprises the second heat exchanger 9 and the first detent 12.

Whatever the operating mode of the refrigerant circuit, the refrigerant passes through the first expansion device 2 and then flows from the bypass point 16 to the connection point 17. In other words, according to a first flow direction Si refrigerant inside the refrigerant circuit 1, the branch point 16 is located upstream of the connection point 17.

These provisions are such that during its journey inside the refrigerant circuit 1, at least a portion of the refrigerant fluid may undergo cascading detents. Upstream of the first expansion device 2, the refrigerant fluid is at a first pressure P 1. Inside the first expansion device 2, the refrigerant fluid undergoes a first expansion so that downstream of the first expansion device 2, the coolant is at a second pressure P2 which is less than the first pressure

Ft.

The refrigerant which borrows the second branch 14 is at a third pressure P3 after undergoing a second expansion inside the second expansion member 5, the third pressure P3 being lower than the second pressure P2. Downstream of the first heat exchanger 6, the refrigerant is at a fourth pressure P4.

It should be noted that, advantageously, a speed of rotation of a compressor that comprises the thermodynamic circuit is controlled to provide a sufficient refrigerant flow rate to the first heat exchanger 6 in order to deliver the first air stream 7 at a temperature required by a user of the motor vehicle.

The refrigerant which borrows the third branch 15 undergoes a change in flow through the first expansion member 12. The refrigerant is thus at a fifth pressure P5 upstream of the second heat exchanger 9 and is a sixth Pe pressure at the outlet of the first expansion member 12.

It is noted that, advantageously, the first expansion member 12 maintains the second heat exchanger 9 at the fifth pressure P5 for better performance of the latter and that the first expansion member 12 supports such a holding of the second heat exchanger 9 at the fifth pressure P5 while compensating for the pressure drop made by the second expansion member 5. In other words, such an architecture makes it possible to prevent the sixth pressure Pe from reigning in the second heat exchanger 9 and to adjust the sixth pressure Pe to the fourth pressure P4.

According to the variant embodiment illustrated in FIG. 2, the refrigerant circuit 1 comprises, in addition to all of the aforementioned elements, an accumulator 18 which is disposed on the second branch 14 between the first heat exchanger 6 and the connection point 17. In this case, the coolant is at a seventh pressure P? at the output of the accumulator 18. Such an architecture makes it possible to maintain the second heat exchanger 9 at the fifth pressure P5 and to adjust the sixth pressure P0 to the seventh pressure P7. Such an architecture is preferred if the first heat exchanger 6 is housed inside the housing of a heating, ventilation and / or air conditioning system 8 and if the thermodynamic circuit 19 comprises a heat exchanger housed on the front face of the motor vehicle.

The refrigerant circuit 1 is advantageously adapted to a thermodynamic circuit 19 of the present invention, such as that illustrated in FIGS. 3 to 12. FIG. 3 illustrates a thermodynamic circuit 19 of the present invention comprising the refrigerant circuit 1 illustrated. in FIG. 1, while FIG. 4 illustrates a thermodynamic circuit 19 of the present invention comprising the refrigerant circuit 1 illustrated in FIG. 2. FIGS. 5 to 12 illustrate respective modes of operation of the thermodynamic circuit 19 applicable to the circuit. of refrigerant 1 illustrated in Figure 1 or Figure 2.

In FIGS. 3 and 4, in addition to the refrigerant circuit 1, the thermodynamic circuit 19 comprises a compressor 20 for carrying the refrigerant at a high HP pressure. The thermodynamic circuit 19 also comprises a third heat exchanger 21 which is arranged to allow a heat exchange with a second air flow 22, such as a flow of air outside the passenger compartment. For this purpose, the third heat exchanger 21 is preferably placed in a front face of the motor vehicle. The thermodynamic circuit 19 comprises a third expansion member 23 inside which the refrigerant is expanded. The thermodynamic circuit 19 comprises a fourth heat exchanger 24 having a first passage 25 and a second passage 26 of coolant which are able to exchange heat with each other. The thermodynamic circuit 19 also comprises a fifth heat exchanger 27 which is arranged to exchange calories with the first air stream 7. This fifth heat exchanger 27 exchanges calories with the first air stream 7 after an exchange of heat. heat between the first heat exchanger 6 and the first air stream 7. In other words, the fifth heat exchanger 27 is preferably disposed downstream of the first heat exchanger 6 in a direction of flow of the first flow of heat. air 7 inside the housing of the heating, ventilation and / or air conditioning system 8. The fifth heat exchanger 27 can be used as a heating radiator while the first heat exchanger 6 can be used as an evaporator.

The thermodynamic circuit 19 has a particular architecture to offer different modes of operation, as described below. More particularly, the thermodynamic circuit 19 comprises several circulation lines 28, 29, 30, 31, 32, which complete the third branch 15, through which the refrigerant circulates or does not circulate in the open or closed position of the control valves. 101, 102, 103, 104, 105 or non-return valves 301, 302, 303 that the circulation lines 28, 29, 30, 31, 32, or the third leg 15, comprise. These lines of circulation 28, 29, 30, 31, 32, and the third branch 15 are connected to each other via the point of derivation 16, of the point of connection 17, junction points referenced 201, 202, 203, 204, 205, 206, 207.

The thermodynamic circuit 19 comprises a first circulation line 28 which successively comprises the compressor 20, a first junction point 201, a second control valve 102, a second junction point 202, the third heat exchanger 21, a third point of contact. junction 203, a first check valve 301 allowing the passage of refrigerant only from the third junction 203 to a fourth junction point 204. Then, the first circulation line 28 successively comprises the first passage 25, a fifth junction 205 a second non-return valve 302 allowing the passage of the refrigerant only from the fifth junction point 205 to a sixth junction point 206 with the first branch 13. Then, the first flow line 28 successively comprises the first expansion device 2 , the branch point 16, the second branch 14 with the first control valve 101 the second expansion element 5, the first heat exchanger 6 and the connection point 17. Then, the first circulation line 28 successively comprises a third control valve 103, a seventh connection point 207, the accumulator 18, the second passage 26 to return to the compressor 20.

The thermodynamic circuit 19 also comprises a second refrigerant circulation line 29 which extends between the first junction point 201 and the sixth junction point 206. The second circulation line 29 comprises, successively, from the first junction point 201 to the sixth junction point 206, the fifth heat exchanger 27 and a fourth control valve 104.

The thermodynamic circuit 19 further comprises a third refrigerant circulation line 30 which extends between the second junction point 202 and the seventh junction point 207 and which comprises a fifth control valve 105.

The thermodynamic circuit 19 also comprises a fourth circulation line 31 which extends between the connection point 17 and the fifth junction point 205 and which comprises a third non-return valve 303 allowing the passage of the refrigerant only from the connection point 17 to the sixth junction point 206.

The thermodynamic circuit 19 finally comprises a fifth circulation line 32 which extends between the third junction point 203 and the fourth junction point 204 and which comprises the third expansion member 23.

Furthermore, the second pass 11 of the second heat exchanger 9 is part of a heat transfer liquid circuit 33. The heat transfer liquid is for example consisting of a mixture of water and glycol, or the like. The coolant circuit 33 comprises a pump 34 for circulating the heat transfer liquid inside the coolant circuit 33. The pump 34 is installed on a first pipe 35 which comprises the coolant circuit 33. The liquid circuit coolant 33 also comprises a three-way valve 36 which distributes the coolant liquid at the outlet of the pump 34, either to a second pipe 37 or to a third pipe 38. The third pipe 38 carries the coolant to exchange calories with a energy source 39, such as a source of electrical energy. According to the invention, this energy source can be formed by one or more batteries, and more particularly by the battery supplying an electric propulsion engine of the vehicle.

Alternatively, the energy source 39 may be a source of mechanical energy, or any other element of the motor vehicle which must be provided with a heat treatment during operation. By extension, the energy source 39 may consist of a participating element of a refrigerant circuit loop dedicated to the thermal control of a particular area of the motor vehicle, including a rear area or the like.

The second conduit 37 forms a bypass route of the third conduit 38. The second conduit 37 and the third conduit 38 meet at a point of attachment 40. The point of attachment 40 is placed upstream of the second pass 11 and the pump 34, according to a second direction of circulation $ 2 of the coolant inside the first pipe 35.

In FIG. 4, the thermodynamic circuit 19 incorporates the refrigerant circuit 1 illustrated in the variant of FIG. 2, the accumulator 18 illustrated in FIG. 3 being positioned on the third branch 15, between the first expansion member 12 and the liaison point 17.

As mentioned above, the thermodynamic circuit 19 is able to operate in various modes with a separate implementation, depending on the mode envisaged, of the first branch 13 and / or the second branch 14 of the refrigerant circuit 1. More particularly, the thermodynamic circuit 19 is able to operate: in a first mode, said air conditioning mode, wherein the first air stream 7 is cooled prior to a delivery of the latter inside the passenger compartment of the vehicle automobile, - in a second mode, said mode air conditioning and cooling of the energy source 39, wherein the first air stream 7 is cooled prior to a delivery of the latter inside the passenger compartment of the motor vehicle and in which the energy source 39 is cooled from the circulation of the coolant, - in a third mode, said air conditioning mode and window demisting of the vehicle automob island, wherein the first air flow 7 is dried and then reheated prior to a delivery of the latter inside the passenger compartment of the motor vehicle, - in a fourth mode, said heat pump or heating mode, wherein the first air stream 7 is heated prior to its delivery to the interior of the passenger compartment of the motor vehicle. - In a fifth mode, said heat pump mode and heating of the energy source 39, wherein the first air stream 7 is heated prior to a delivery of the latter inside the passenger compartment of the motor vehicle and in which the energy source 39 is heated from the circulation of the coolant, - in a sixth mode, said heat pump mode and cooling of the energy source 39, wherein the first air flow 7 is heated prior to a delivery of the latter inside the passenger compartment of the motor vehicle and in which the energy source 39 is cooled from the circulation of the coolant liquid, in a seventh mode of operation, said cooling of energy source, wherein the energy source 39 is cooled. in an eighth mode of operation, known as energy source heating, in which the energy source 39 is heated up.

By convention in FIGS. 5 to 12, the circulation lines 28, 29, 30, 31, 32, 33, the branches 13, 14, 15 and the lines 35, 37, 38 through which no fluid or liquid flows are represented. in dashed lines, while the circulation lines 28, 29, 30, 31, 32, 33, the branches 13, 14, 15 and the lines 35, 37, 38 through which the cooling fluid or the coolant circulates are represented in full line.

By convention still in FIGS. 5 to 12, the circulation lines 28, 29, 30, 31, 32, 33, the branches 13, 14, 15 and the ducts 35, 37, 38 are illustrated by arrows whose tips symbolize a direction of flow of the coolant or coolant within the circulation lines 28, 29, 30, 31, 32, 33, branches 13, 14, 15 or lines 35, 37, 38.

In Figure 5, the thermodynamic circuit 19 is used in a first mode, called air conditioning, for cooling the first air flow 7 prior to its delivery to the interior of the passenger compartment. In this configuration, the first expansion member 12, the fourth control valve 104, the fifth control valve 105 and the third check valve 303 are closed and the pump 34 is stopped.

Thus, the refrigerant borrows only the first circulation line 28. In other words, the refrigerant is compressed inside the compressor 20 to be brought to a high pressure HP, then flows to the first point of junction 201, then crosses the second control valve 102 (open position), then flows to the second junction point 202, then flows inside the third heat exchanger 21 inside which the refrigerant yields calories to the second flow of heat. 22. The refrigerant circulates to the third junction 203, then takes the first non-return valve 301, bypassing the third expansion member 23, and then flows to the fourth junction point 204, then takes the first passage 25 inside which the refrigerant yields calories to the refrigerant present in the second pass 26. Then, the fluid ref rigger circulates to the fifth point of junction 205, then takes the second non-return valve 302 (open position), then flows to the sixth junction point 206 and borrows the first branch 13, then flows inside the first expansion device 2 in which the refrigerant undergoes a first expansion and switches from the high pressure HP to a first low pressure BPi lower than the high pressure HP.

The first expansion device 2 is configured to lower the high pressure HP and generate a first low pressure BPi. Then, the refrigerant circulates to the bypass point 16 where the refrigerant borrows the second branch 14 to pass through the first control valve 101 (open position), the second expansion member 5 within which the refrigerant undergoes a second expansion and changes from the first low pressure BPi to a second low BPi lower than the first low pressure BPi. The second expansion member 5 is configured to adjust the second low pressure BP2. Then, the refrigerant circulates inside the first heat exchanger 6 to cool the first air flow 7, then flows to the connection point 17, then passes through the third control valve 103 (open position), then circulates to the seventh junction point 207, then passes through the accumulator 18 inside which any residue of liquid coolant is retained, then flows inside the second passage 26 of the fourth heat exchanger 24 to return to the compressor 20.

These arrangements are such that the coolant is at high pressure HP between the compressor 20 and the first expansion device 2, and that the coolant is at the first low pressure BPi between the first expansion device 2 and the second expansion device 5, and that the coolant is at the second low pressure BPi between the second expansion member 5 and the compressor 20. It finally results that in this configuration, the coolant successively undergoes two detents.

In FIG. 6, the thermodynamic circuit 19 is used in a second mode, called air-conditioning, for cooling the first air flow 7 prior to its delivery inside the passenger compartment and simultaneous cooling of the energy source 39. In this configuration, the fourth control valve 104, the fifth control valve 105 and the third check valve 303 are closed. In this configuration, the pump 34 is in operating mode to circulate the heat transfer fluid inside the heat transfer liquid circuit 33 and the three-way valve 36 allows a circulation of refrigerant fluid inside the third pipe 38 and prohibits a circulation of refrigerant inside the second conduit 37.

Thus, the refrigerant borrows the first circulation line 28 and advantageously the third branch 15, compared to the previously described mode. In other words, the refrigerant is compressed inside the compressor 20 at a high HP pressure, then flows to the first junction point 201, then passes through the second control valve 102 (open position), and then flows until second junction point 202, then circulates inside the third heat exchanger 21 inside which the coolant transfers calories to the second air flow 22. Then, the refrigerant circulates to the third junction point 203, then takes the first non-return valve 301, bypassing the third expansion member 23, then flows to the fourth junction point 204, then borrows the first passage 25 inside which the coolant captures calories from the refrigerant present in the second pass 26. Then the refrigerant flows to the fifth point of junction 205, then borrows the second non-return valve 302 (open position), then flows to the sixth junction point 206 and takes the first branch 13, then flows inside the first expansion device 2 where the refrigerant undergoes a first expansion and passes HP high pressure at a first low pressure BPi lower than the high pressure HP. Then, the refrigerant circulates to the bypass point 16 where the refrigerant borrows the second branch 14 and the third branch 15.

The fraction of refrigerant flowing through the second branch 14 passes through the first control valve 101 (open position), the second expansion member 5 inside which the refrigerant undergoes a second expansion and changes from the first low pressure BPi to the second lower BPi pressure lower than the first BPi low pressure. The second expansion member 5 is configured to adjust the second low pressure BP2. Then the refrigerant circulates inside the first heat exchanger 6 to cool the first air stream 7, then flows to the connection point 17.

The fraction of refrigerant fluid that takes the third branch 15 circulates inside the first pass 10 of the second heat exchanger 9 to capture calories to the heat transfer liquid present inside the second pass 11, then passes through the first organ detent 12 (open position) which holds the second heat exchanger 9 at the second low pressure BP2. The first expansion member 12 adjusts the flow rate and the pressures downstream of the first heat exchanger 6 and the second heat exchanger 9. Then the refrigerant reaches the connection point 17. Then the refrigerant passes through the third control valve 103 (open position), then flows to the seventh junction point 207, then passes through the accumulator 18 inside which any liquid refrigerant remaining liquid is retained, a gaseous phase of the refrigerant circulating inside the second passage 26 of the fourth heat exchanger 24 to return to the compressor 20.

These arrangements are such that the coolant is at high pressure HP between the compressor 20 and the first expansion device 2, and that the coolant is at the first low pressure BPi between the first expansion device 2 and the second expansion device 5, and between the first expansion device 2 and the first expansion member 12, and that the coolant is at the second low pressure BP2 between the second expansion member 5 and the compressor 20 and between the first member 12 and the compressor 20.

Furthermore, the pump 34 being in operation and the three-way valve 36 being configured to allow a circulation of the heat transfer fluid only inside the first pipe 35 and the third pipe 38, the heat transfer fluid captures calories at the level of the energy source 39 to give them to the coolant at the level of second heat exchanger 9. As a result, in this configuration, the coolant undergoes two successive detents to optimally cool the first air flow 7 and the flow rate of refrigerant inside the second heat exchanger 9 is regulated.

In FIG. 7, the thermodynamic circuit 19 is used in a third mode, called air conditioning and defogging of windows of the motor vehicle, in which the first air flow 7 is dried and then reheated prior to its delivery inside the vehicle. cabin of the motor vehicle. In this configuration, the first expansion member 12, the fifth control valve 105 and the third check valve 303 are closed and the pump 34 is stopped.

Thus the refrigerant borrows the first circulation line 28 and the second circulation line 29. In other words, the refrigerant is compressed inside the compressor 20 to be brought to a high pressure HP, then flows to the first point 201. A fraction of the refrigerant borrows the second circulation line 29 and another fraction of the refrigerant continues to circulate inside the first circulation line 28. The latter crosses the second control valve 102 (open position ), then flows to the second junction point 202, then flows inside the third heat exchanger 21 inside which the refrigerant yields calories to the second air stream 22. Then, this fraction of fluid refrigerant circulates to the third point of junction 203, then takes the first non-return valve 301, bypassing the third org expansion ring 23, then flows to the fourth point of junction 204, then takes the first passage 25 within which the refrigerant fraction yields calories to the refrigerant present in the second pass 26. Then the refrigerant circulates until the fifth junction point 205, then takes the second non-return valve 302 (open position), then flows to the sixth junction point 206 where the refrigerant fraction found the other fraction. The latter, from the first junction point 201, circulates inside the fifth heat exchanger 27, to heat the first cooled air stream 7 and advantageously dried during its prior crossing of the first heat exchanger 6, then through the fourth control valve 104 (open position) before joining the sixth junction point 206.

The refrigerant fluid also circulates in the first branch 13, then flows inside the first expansion device 2 where the refrigerant undergoes a first expansion and changes from the high pressure HP to a first low pressure BPi lower than the high pressure HP . Then the refrigerant circulates to the bypass point 16 where the refrigerant borrows the second branch 14 to pass through the first control valve 101 (open position), the second expansion member 5 inside which the refrigerant undergoes a second expansion and goes from the first low pressure BPi to a second low pressure BPi lower than the first low pressure BPi, then flows inside the first heat exchanger 6 to cool and dry the first air flow 7, then circulates to the connection point 17, then passes through the third control valve 103 (open position), then flows to the seventh junction point 207, then passes through the accumulator 18 inside which a possible residue of liquid refrigerant fluid. is retained, then circulates inside the second passage 26 of the fourth heat exchanger 24 to return to the compressor 20.

These arrangements are such that the coolant is at high pressure HP between the compressor 20 and the first expansion device 2 as well as between the compressor 20 and the sixth junction point 206 and that the coolant is at the first low pressure BPi between the first expansion device 2 and the second expansion device 5, and that the coolant is at the second low pressure BP2 between the second expansion member 5 and the compressor 20. As a result, in this configuration, the refrigerant successively undergoes two detents to cool and dry the first air stream 7, the first heat exchanger 6 acting as an evaporator against the walls of which a moisture carried by the first air flow 7 condenses, the first the dried air stream 7 is then heated as it passes through the fifth heat exchanger 27, the latter being used as the cooler of the refrigerant.

In Figure 8, the thermodynamic circuit 19 is used in a fourth mode, said heat pump, wherein the first air stream 7 is heated prior to its delivery to the interior of the passenger compartment of the motor vehicle. In this configuration, the first expansion element 12, the second control valve 102, the third control valve 103 and the first non-return valve 301 are closed and the pump 34 is stopped.

Thus, the refrigerant borrows the second circulation line 29, the third circulation line 30, the fourth circulation line 31, the fifth circulation line 32 and partially the first circulation line 28. In other words, the refrigerant fluid is compressed inside the compressor 20 to be brought to a high pressure HP, then flows to the first point of junction 201. The refrigerant then borrows the second line of circulation 29 and passes through the fifth heat exchanger 27 inside which refrigerant transfers calories to the first air stream 7 to heat the latter prior to its delivery to the interior of the passenger compartment of the motor vehicle.

Then, the refrigerant passes through the fourth control valve 104 (open position) to reach the sixth junction point 206. Then the refrigerant borrows the first branch 13, then flows inside the first expansion device 2 which is totally open so that no relaxation occurs. Then the refrigerant circulates to the bypass point 16 where the refrigerant borrows the second branch 14 to pass through the first control valve 101 (open position), the second expansion member 5 inside which the refrigerant undergoes a first expansion and HP high pressure passes at a first BPi low pressure lower than the HP high pressure, then circulates inside the first heat exchanger 6 to cool and dry the first air flow 7, then circulates to at the point of connection 17. Then, the refrigerant borrows the fourth circulation line 31 and passes through the third non-return valve 303 (open position) to reach the fifth junction point 205. Then, the refrigerant borrows the first passage 25 the fourth heat exchanger 24 inside which the refrigerant yields calories to the refrigerant present in the interior 26. The refrigerant then reaches the fourth junction point 204 and then passes through the third expansion member 23 inside which the refrigerant undergoes a second expansion and goes from the first low pressure BPi to a second low. BP2 pressure lower than the first low pressure BPi, then circulates inside the third heat exchanger 21 inside which the refrigerant captures calories to the second air stream 22, ie is heated in contact with the second stream of air 22. Then the coolant reaches the second junction point 202 to take the third circulation line 30 and cross the fifth control valve 105 (open position) and join the seventh junction point 207 to take the first line of circulation 28. The refrigerant then passes through the accumulator 18 inside which a possible residue liquid refrigerant fluid is retained, then circulates inside the second passage 26 of the fourth heat exchanger 24 to return to the compressor 20.

These arrangements are such that the coolant is at high pressure HP between the compressor 20 and the second expansion member 5 and that the coolant is at the first low pressure BPi between the second expansion member 5 and the third expansion member 23. , and that the coolant is at the second low pressure BPi between the third expansion member 23 and the compressor 20. Π finally results that, in this configuration, the refrigerant at the outlet of the compressor 2 heats the first air flow 7 inside the fifth heat exchanger 27, then successively undergoes two detents including a first expansion inside the second expansion member 5 to ensure that the pressure remains below a certain threshold inside the first heat exchanger 6 acting as an evaporator against the walls of which a moisture carried by the first air flow 7 condenses, the pr the dried air stream 7 is then warmed as it passes through the fifth heat exchanger 27.

In FIG. 9, the thermodynamic circuit 19 is used in a fifth mode, called heat pump mode and heating of the energy source 39, in which the first air stream 7 is heated before it is delivered inside. of the passenger compartment of the motor vehicle and wherein the energy source 39 is heated from the circulation of the coolant. In this configuration, the first expansion member 12 is open to provide a refrigerant flow rate inside the second heat exchanger 9, while the second control valve 102, the third control valve 103 and the first valve -return 301 are closed. The pump 34 is in operation and the three-way valve 36 allows a circulation of the coolant between the first pipe 35 and the third pipe 38 and prevents such circulation inside the second pipe 37.

Thus, the refrigerant borrows the second circulation line 29, the third circulation line 30, the fourth circulation line 31, the fifth circulation line 32 and advantageously the third branch 15, as well as partially the first circulation line 28. In other words, the refrigerant is compressed inside the compressor 20 to be brought to a high HP pressure, then flows to the first junction point 201. The refrigerant then borrows the second line of circulation 29 and passes through the fifth heat exchanger 27 inside which the coolant transfers calories to the first air stream 7 to heat the latter prior to its delivery to the interior of the passenger compartment of the motor vehicle. Then the refrigerant passes through the fourth control valve 104 (open position) to reach the sixth junction point 206. Then the refrigerant borrows the first branch 13, then flows inside the first expansion device 2 which is fully open so that no relaxation occurs there. Then the refrigerant circulates to the bypass point 16 where a fraction of the refrigerant borrows the second branch 14 and the other fraction of the refrigerant borrows the third branch 15.

The fraction of the refrigerant flowing through the second branch 14 passes through the first control valve 101 (open position), the second expansion member 5 inside which the coolant undergoes a first expansion and switches from the high pressure HP to a first low pressure BPi lower than the high pressure HP, then circulates inside the first heat exchanger 6 to cool and dry the first air flow 7, then flows to the connection point 17.

The fraction of refrigerant fluid that takes the third branch 15 circulates inside the first pass 10 of the second heat exchanger 9 to yield calories to the heat transfer liquid present inside the second pass 11, then passes through the first organ trigger 12 (open position). The first expansion member 12 adjusts the flow rate and the pressures downstream of the first heat exchanger 6 and the second heat exchanger 9. Then, this refrigerant fraction reaches the connection point 17. Then, the refrigerant borrows the fourth circulation line 31 and passes through the third non-return valve 303 (open position) to reach the fifth junction point 205. Then, the refrigerant borrows the first passage 25 of the fourth heat exchanger 24 inside which the refrigerant transfers heat to the coolant present inside the second passage 26. Then the coolant reaches the fourth junction point 204 and then passes through the third expansion member 23 within which the refrigerant undergoes a second expansion and passes from the first low pressure BPi to a second low pressure BP2 lower than the first low pressure B Pi, then circulates inside the third heat exchanger 21 inside which the coolant captures calories to the second air stream 22. Then the refrigerant reaches the second junction 202 to take the third line of 30 and cross the fifth control valve 105 (open position) and join the seventh junction point 207 to prevent the first line of circulation 28. The refrigerant then passes through the accumulator 18 within which a possible fluid residue liquid refrigerant is retained, then circulates inside the second passage 26 of the fourth heat exchanger 24 to return to the compressor 20.

These arrangements are such that the refrigerant fluid is at high pressure HP between the compressor 20 and the second expansion member 5 as well as between the compressor 2 and the first expansion member 12, and that the coolant is at the first low pressure BPi between the second expansion member 5 and the third expansion member 23 and between the first expansion member 12 and the third expansion member 23, and that the coolant is at the second low pressure BP2 between the third member 23 and the compressor 20. n finally results that, in this configuration, the refrigerant at the outlet of the compressor 2 heats the first air flow 7 inside the fifth heat exchanger 27 and simultaneously heats the heat transfer liquid to finally heating the energy source 39, and undergoes either a relaxation inside the second expansion member 5, or a flow adjustment pa via the first expansion member 12, in particular to ensure that the pressure remains below a certain threshold inside the first heat exchanger 6 acting as an evaporator against the walls of which a moisture carried by the first air flow 7 is condensed, the first dry air stream 7 then being heated as it passes through the fifth heat exchanger 27.

In FIG. 10, the thermodynamic circuit 19 is used in a sixth mode, called heat pump mode and cooling of the energy source 39, in which the first air stream 7 is heated before it is delivered inside. of the passenger compartment of the motor vehicle and in which the energy source 39 is cooled, from the circulation of the coolant. In this configuration, the first expansion member 12 is completely open, while the first control valve 101, the second control valve 102, the fifth control valve 105, the first non-return valve 301 and the second anti-return valve 302 return are closed and the pump 34 is in operation and the three-way valve 36 allows a circulation of the coolant between the first pipe 35 and the third pipe 38 and prohibits such circulation inside the second pipe 37.

Thus, the refrigerant borrows the second circulation line 29, the fourth circulation line 31 and advantageously the third branch 15, as well as a portion of the first circulation line 28. In other words, the refrigerant is compressed to the inside the compressor 20 to be brought to a high HP pressure, then flows to the first junction point 201. The refrigerant then borrows the second line of circulation 29 and passes through the fifth heat exchanger 27 within which the fluid refrigerant yields calories to the first air stream 7 to heat the latter prior to its delivery inside the passenger compartment of the motor vehicle. Then the refrigerant passes through the fourth control valve 104 (open position) to reach the sixth junction point 206. Then the refrigerant borrows the first branch 13, then flows inside the first expansion device 2 inside. of which the coolant undergoes the only expansion that the coolant undergoes inside the thermodynamic circuit 19, according to this mode of operation.

Thus, inside the first expansion device 2, the refrigerant fluid passes from the HP high pressure to the low BP pressure. Then the refrigerant circulates to the bypass point 16 where the refrigerant borrows the third branch 15. The refrigerant circulates inside the first pass 10 of the second heat exchanger 9 to capture calories present in the coolant present inside the second pass 11, then through the first expansion member 12, the latter being fully open. Then the coolant reaches the point of connection 17. The refrigerant then borrows the first flow line 28 and passes through the third control valve 103 (open position) and then passes through the accumulator 18 within which a possible fluid residue liquid refrigerant is retained, then circulates inside the second passage 26 of the fourth heat exchanger 24 to return to the compressor 20.

These arrangements are such that the coolant is at high pressure HP between the compressor 20 and the first expansion device 2, and that the coolant is at the low pressure LP between the first expansion device 2 and the compressor 20. Π finally results that, in this configuration, the refrigerant fluid at the outlet of the compressor 2 heats the first air stream 7 which passes through the fifth heat exchanger 27 and cools the heat transfer liquid in order to finally cool the energy source 39.

In FIG. 11, the thermodynamic circuit 19 is used in a seventh mode, said cooling of the energy source 39. In this configuration, the first control valve 101, the fourth control valve 104, the fifth control valve 105 and the third non-return valve 303 are closed. In this configuration, the pump 34 is in operating mode for circulating the heat transfer liquid inside the heat transfer liquid circuit 33 and the three-way valve 36 allows a circulation of refrigerant fluid inside the third pipe 38 and prohibits a circulation of refrigerant inside the second conduit 37.

Thus, the refrigerant borrows partially the first circulation line 28 and advantageously the third branch 15. In other words, the refrigerant is compressed inside the compressor 20 at a high pressure HP, then flows to the first junction point 201, then passes through the second control valve 102 (open position), then flows to the second junction point 202, then flows inside the third heat exchanger 21 inside which the refrigerant yields calories to the second air flow 22. The refrigerant then circulates to the third junction 203, then takes the first non-return valve 301, bypassing the third expansion member 23, and then flows to the fourth point of junction 204 , then borrows the first passage 25 inside which the coolant transfers calories to the refrigerant present in the second 26. Then, the refrigerant circulates to the fifth junction 205, then takes the second non-return valve 302 (open position), then flows to the sixth junction point 206 and borrows the first branch 13, then circulates inside the first expansion device 2 where the refrigerant undergoes the single expansion that the refrigerant undergoes inside the thermodynamic circuit 19, according to this mode of operation. Thus, the coolant changes from HP high pressure to a lower BP pressure lower than the HP high pressure. Then the refrigerant circulates to the bypass point 16 where the refrigerant borrows the third branch 15. The refrigerant circulates inside the first pass 10 of the second heat exchanger 9 to capture calories heat transfer liquid present at the inside of the second pass 11, then passes through the first expansion member 12, placed in fully open position and within which the refrigerant does not undergo any pressure drop. Then the coolant reaches the point of connection 17. The refrigerant then passes through the third control valve 103 (open position), then flows to the seventh junction point 207, then passes through the accumulator 18 inside which a any residual liquid refrigerant fluid is retained and then circulates inside the second passage 26 of the fourth heat exchanger 24 to return to the compressor 20.

These arrangements are such that the coolant is at high pressure HP between the compressor 20 and the first expansion device 2, and that the coolant is at the low pressure LP between the first expansion device 2 and the compressor 20.

Furthermore, the pump 34 being in operation and the three-way valve 36 being configured to allow a circulation of the heat transfer fluid only inside the first pipe 35 and the third pipe 38, the heat transfer fluid captures calories at the level of the energy source 39 to give them to the coolant at the second heat exchanger 9. As a result, in this configuration, the coolant undergoes a single expansion to optimally cool the energy source 39.

In FIG. 12, the thermodynamic circuit 19 is used in an eighth mode known as the heating up of the energy source 39, in which the energy source 39 is heated from the circulation of the coolant. In this configuration, the first expansion member 12 is completely open so that the refrigerant does not undergo any pressure drop or flow reduction, while the first control valve 101, the second control valve 102, the third control valve 103 and the first non-return valve 301, the second non-return valve 302 are closed. The pump 34 is in operation and the three-way valve 36 allows a circulation of the coolant between the first pipe 35 and the third pipe 38 and prevents such circulation inside the second pipe 37.

Thus the refrigerant borrows the second circulation line 29, the third circulation line 30, the fourth circulation line 31, the fifth circulation line 32 and preferably the third leg 15 and partially the first circulation line 28. In other words , the refrigerant is compressed inside the compressor 20 to be brought to a high HP pressure, then flows to the first junction point 201. The refrigerant then flows through the second circulation line 29 and passes through the fifth heat exchanger. heat 27 inside which the refrigerant yields calories to the first air stream 7 to heat the latter prior to its delivery to the interior of the passenger compartment of the motor vehicle.

According to a variant, no first air flow 7 circulates inside the housing of the heating, ventilation and / or air conditioning system 8, so that the refrigerant does not yield any calories inside. of the fifth heat exchanger 27. Then, the refrigerant passes through the fourth control valve 104 (open position) to reach the sixth junction point 206. Then the refrigerant borrows the first branch 13, then flows inside the first detent device 2 which is fully open so that no detent occurs therein. Then the refrigerant circulates to the bypass point 16 where the refrigerant borrows the third branch 15. The refrigerant circulates inside the first pass 10 of the second heat exchanger 9 to give calories to the coolant present in the inside of the second pass 11, then passes through the first expansion member 12 which is in the fully open position and within which no pressure drop occurs. Then the coolant reaches the point of connection 17. The refrigerant then takes the fourth circulation line 31 and passes through the third non-return valve 303 (open position) to reach the fifth junction point 205. Then, the refrigerant borrows the first passage 25 of the fourth heat exchanger 24 inside which the coolant transfers calories to the coolant present inside the second passage 26. Then the coolant reaches the fourth junction point 204 and then passes through the third expansion member 23 within which the refrigerant undergoes the single expansion that the refrigerant undergoes inside the thermodynamic circuit 19, according to this mode of operation. Thus, the coolant changes from the high pressure HP to a low pressure BP lower than the high pressure HP, then circulates inside the third heat exchanger 21 inside which the refrigerant captures calories to the second flow of heat. 22. The refrigerant then reaches the second junction 202 to take the third circulation line 30 and cross the fifth control valve 105 (open position) and join the seventh junction point 207 to take the first line of circulation 28 The refrigerant then passes through the accumulator 18 inside which a residual liquid refrigerant fluid is retained, then flows inside the second passage 26 of the fourth heat exchanger 24 to return to the compressor 20.

These arrangements are such that the refrigerant fluid is at high pressure HP between the compressor 20 and the third expansion member 23 and that the coolant is at the low pressure BP between the third expansion member 23 and the compressor 20. Π results finally, in this configuration, the refrigerant fluid at the outlet of the compressor 2 quickly and efficiently heats the heat transfer fluid to finally heat the energy source 39, and undergoes a single expansion inside the third expansion member 23. Π of all these provisions that the thermodynamic circuit 19 of the present invention associated with the coolant circuit 33 is able to be thermally controlled effectively. More particularly. Such an arrangement of the thermodynamic circuit 19 makes it possible to separately control the first heat exchanger 6, the first expansion device 2 and the first expansion device 12 from a coordinated control of the first heat exchanger 6 and the second heat exchanger 9, especially when the latter two are solicited.

Such an arrangement of the thermodynamic circuit 19 allows smooth smooth transition of the mass flow rate from one to the other of the second branch 14 and the third branch 15, the third heat exchanger 21 indifferently playing the role. evaporator or condenser. More particularly, the first expansion device 2 is able to optimize the HP high pressure for a supercritical or subcritical refrigerant fluid from a mass flow control, the relaxation being a consequence of mass flow control. The separation into two branches at the branch point 16 allows the second branch 14 to reduce the pressure at the first heat exchanger 6 through the second expansion device 3 present upstream of the first heat exchanger 6, the pressure of refrigerant prevailing inside the first heat exchanger 6 being lower than the pressure of the refrigerant inside the second heat exchanger 9. The separation in two branches at the branch point 16 allows for the third branch It also follows from all these provisions that the optimization of the HP high pressure also makes it possible to optimize a coefficient of performance of the thermodynamic circuit 19, commonly referred to as the thermodynamic circuit. COP according to the Anglo-Saxon acronym "Coefficient Of Performance". Thus, when the optimized high pressure is reached, for a given temperature setpoint inside the passenger compartment of the motor vehicle, the consumption of the compressor 2 is minimal.

The temperature of the first air stream 7 is controlled by the mass flow rate of the refrigerant fluid which is placed under the control of the speed of rotation of the compressor 2. The second expansion member 5 is provided for an evaporation temperature to occur. at a lower pressure than for cooling the coolant. In any one of the "heat pump" modes presented above, the second expansion member 5 can also prevent too high a pressure inside the first heat exchanger 6, when the latter plays a role. condenser or gas cooler. It also follows from all these arrangements that the first expansion member 12 is able not only to maintain an intermediate pressure inside the second heat exchanger 9, in particular from a mass flow control which controls itself an overheating at the outlet of the second heat exchanger 9, to reach the temperature required for the energy source 39, but also to harmonize a refrigerant pressure at the outlet of the first heat exchanger 6 and the second heat exchanger heat 9. Π is also necessary to limit the pressure of the refrigerant at the outlet of the second heat exchanger 9 because, even in the presence of the first expansion member 12, the pressure of the refrigerant at the outlet of the second heat exchanger 9 does not must not exceed the optimized high pressure required for the temperature of the first heat exchanger 6, in any of the mod It also follows from all these provisions that the thermodynamic circuit 19 is able to provide operations in various modes, based on the following behaviors of the first heat exchanger. 6 and the second heat exchanger 9, as described in the following table:

FIG. 13 shows a Mollier diagram illustrating a thermal behavior of the refrigerant circuit 1 illustrated in FIG. 2 and operating according to the second mode illustrated in FIG. 6, said air conditioning and cooling mode of the energy source 39, wherein the first air stream 7 is cooled prior to delivery to the interior of the passenger compartment of the motor vehicle and wherein the energy source 39 is cooled from the circulation of the coolant. For the purposes of the example, the refrigerant fluid is supercritical, especially a carbon dioxide.

The segment AB represents the compression of the refrigerant fluid operated by the compressor 20 from the second low pressure BP2 to the high pressure HP during which the pressure and the enthalpy of the coolant increase. The segment BC represents isobaric cooling of the coolant successively inside the third heat exchanger 21 and then the fourth heat exchanger 24. The segment CD represents a first isenthalpic expansion carried out inside the first expansion device 2 to 1 inside which the coolant passes from the high pressure HP to the first low pressure BPi. The segment DE represents a second isenthalpic expansion carried out inside the second expansion member 5 inside which the coolant flows from the first low pressure BPi to the second low pressure BP2. The segment EF represents an isobaric cooling of the refrigerant inside the first heat exchanger 6. The segment DH represents an isobaric cooling of the refrigerant inside the second heat exchanger 9. The segment HE represents an isenthalpic expansion carried out inside the first expansion member 12. The segment FA represents in particular a heating of the refrigerant inside the third heat exchanger 21.

Claims (25)

A refrigerant circuit (1) within which a refrigerant fluid is circulating, the refrigerant circuit (1) comprising at least a first heat exchanger (6) and at least a second heat exchanger ( 9), characterized in that the refrigerant circuit (1) comprises a first branch (13) provided with a first expansion device (2), the first branch (13) having a branch point (16) common to a second leg (14) and a third leg (15), the second leg (14) being provided with a second expansion device (3) and the first heat exchanger (6), the second expansion device (3) ) being interposed between the branch point (16) and the first heat exchanger (6), the third branch (15) being provided with the second heat exchanger (9) and a first expansion member (12), the second heat exchanger (9) being interposed between the point bypass (16) and the first detent (12). 2. Refrigerant circuit (1) according to claim 1, wherein the second expansion device (3) comprises a second expansion member (5) constant section. 3. Refrigerant circuit (1) according to claim 2, wherein the second expansion device (3) comprises a first control valve (101) of a coolant circulation in the second branch (14) interposed between the bypass point (16) and the second expansion member (5). 4. Refrigerant circuit (1) according to any one of the preceding claims, wherein the first expansion member (12) is a coolant flow rate control valve. 5. Refrigerant circuit (1) according to any one of the preceding claims, wherein the refrigerant circuit (1) is provided with a battery (18). The refrigerant circuit (1) according to claim 5, wherein the accumulator (18) is interposed between the first heat exchanger (6) and a connection point (17) common to the second leg (14) and in the third limb (15). The refrigerant circuit (1) according to claim 5, wherein the accumulator (18) is disposed downstream of a connection point (17) common to the second leg (14) and to the third leg (15). ), according to a direction of circulation of the refrigerant in the refrigerant circuit (1). Coolant circuit (1) according to any one of the preceding claims, wherein the first heat exchanger (6) is arranged to heat-treat a first air flow (7) and in that the second heat exchanger heat (9) is arranged to exchange heat with a coolant circulating inside a coolant circuit (33) comprising a power source (39). 9. Refrigerant circuit (1) according to any one of the preceding claims, wherein the third leg (15) is provided with a first pass (10) of the second heat exchanger (9). Thermodynamic circuit (19) comprising a refrigerant circuit (1) according to any one of the preceding claims. The thermodynamic circuit (19) according to claim 10, wherein a first circulation line (28) successively comprises a compressor (20), a first connection point (201), a second control valve (102), a second junction point (202), third heat exchanger (21), third junction point (203), first non-return valve (301), fourth junction point (204), first passage (25) a fourth heat exchanger (24), a fifth junction point (205), a second non-return valve (302), a sixth junction point (206), the first branch (13), the junction point (16), the second leg (14), a connecting point (17) common to the second leg (14) and the third leg (15), a third control valve (103), a seventh connecting point ( 207) and the second passage (26) of the fourth heat exchanger (24) to return to the compressor (20). Thermodynamic circuit (19) according to claim 11, comprising a second refrigerant circulation line (29) extending between the first junction point (201) and the sixth junction point (206), the second line circulation device (29) comprising, successively from the first junction point (201) to the sixth junction point (206), a fifth heat exchanger (27) and a fourth control valve (104). A thermodynamic circuit (19) according to any one of claims 11 to 12, comprising a third refrigerant circulation line (30) extending between the second junction point (202) and the seventh junction point ( 207) and which comprises a fifth control valve (105). A thermodynamic circuit (19) according to any one of claims 11 to 13, comprising a fourth circulation line (31) extending between the connection point (17) and the fifth junction point (205) and which comprises a third non-return valve (303). The thermodynamic circuit (19) according to any one of claims 11 to 14, comprising a fifth circulation line (32) extending between the third junction point (203) and the fourth junction point (204) and which comprises a third detent member (23). 16. An assembly (19, 33) formed of the thermodynamic circuit (19) according to any one of claims 10 to 15 and a coolant circuit (33), wherein the coolant circuit (33) comprises a first pipe (35) comprising a pump (34), a second pass (11) of the second heat exchanger (9) and a three-way valve (36) which distributes the heat transfer fluid either to a second pipe (37) or to a third line (38), the second line (37) being a bypass line of the third line (38), the third line (38) being arranged to exchange calories with the energy source (39). 17. A method of implementing the assembly (19, 33) according to claim 16, wherein the compressor (20) is operated to carry the refrigerant at a high pressure (HP). 18. A method of implementation according to claim 17 of the assembly (19, 33) in a first mode, wherein the first expansion device (2) allows expansion, the first expansion member (12) is closed, the first control valve (101) is open, the second control valve (102) is open, the third control valve (103) is open, the fourth control valve (104) is closed, the fifth control valve ( 105) is closed, the first non-return valve (301) is open, the second non-return valve (302) is open, the third non-return valve (303) is closed and the pump (34) is on stop. 19. A method of implementation according to claim 17 of the assembly (19, 33) in a second mode, wherein the first expansion device (2) allows expansion, the first expansion member (12) is open, the first control valve (101) is open, the second control valve (102) is open, the third control valve (103) is open, the fourth control valve (104) is closed, the fifth control valve ( 105) is closed, the first check valve (301) is open, the second check valve (302) is open, the third check valve (303) is closed and the pump (34) is in operation. 20. A method of implementation according to claim 17 of the assembly (19, 33) in a third mode, wherein the first expansion device (2) allows expansion, the first expansion member (12) is closed, the first control valve (101) is open, the second control valve (102) is open, the third control valve (103) is open, the fourth control valve (104) is open, the fifth control valve ( 105) is closed, the first non-return valve (301) is open, the second non-return valve (302) is open, the third non-return valve (303) is closed and the pump (34) is on stop. 21. A method of implementation according to claim 17 of the assembly (19, 33) in a fourth mode, wherein the first expansion device (2) allows expansion, the first expansion member (12) is closed, the first control valve (101) is open, the second control valve (102) is closed, the third control valve (103) is closed, the fourth control valve (104) is open, the fifth control valve ( 105) is open, the first non-return valve (301) is closed, the second non-return valve (302) is closed, the third non-return valve (303) is open and the pump (34) is open. stop. 22. A method of implementation according to claim 17 of the assembly (19, 33) in a fifth mode, wherein the first expansion device (2) allows expansion, the first expansion member (12) is open, the first control valve (101) is open, the second control valve (102) is closed, the third control valve (103) is closed, the fourth control valve (104) is open, the fifth control valve ( 105) is open, the first check valve (301) is closed, the second check valve (302) is closed, the third check valve (303) is open and the pump (34) is in operation. 23. A method of implementation according to claim 17 of the assembly (19, 33) in a sixth mode, wherein the first expansion device (2) allows expansion, the first expansion member (12) is open, the first control valve (101) is closed, the second control valve (102) is closed, the third control valve (103) is open, the fourth control valve (104) is open, the fifth control valve ( 105) is closed, the first check valve (301) is closed, the second check valve (302) is closed, the third check valve (303) is closed and the pump (34) is operating. 24. A method of implementation according to claim 17 of the assembly (19, 33) in a seventh mode, wherein the first expansion device (2) allows expansion, the first expansion member (12) is open, the first control valve (101) is closed, the second control valve (102) is open, the third control valve (103) is open, the fourth control valve (104) is open, the fifth control valve ( 105) is closed, the first check valve (301) is open, the second check valve (302) is open, the third check valve (303) is closed and the pump (34) is in operation. 25. Implementation method according to claim 17 of the assembly (19, 33) in an eighth mode, wherein the first expansion device (2) allows expansion, the first expansion member (12) is open, the first control valve (101) is closed, the second control valve (102) is closed, the third control valve (103) is closed, the fourth control valve (104) is open, the fifth control valve ( 105) is open, the first check valve (301) is closed, the second check valve (302) is closed, the third check valve (303) is open and the pump (34) is in operation.