FR2974624A1 - ASSEMBLY COMPRISING A REFRIGERANT FLUID CIRCUIT AND A HEAT TRANSFER CIRCUIT - Google Patents

Abstract

The invention relates to an assembly comprising a refrigerant circuit 1 and a heat transfer fluid circuit 2 which thermally exchange with each other by means of a refrigerant / heat transfer fluid exchanger 30, said assembly comprising a storage device thermal 16 which exchanges thermally with the coolant and with the coolant, wherein the coolant circuit 1 comprises a bypass means 13 of the thermal storage device 16 and a coolant flow management means 61 arranged so that the flow rate of refrigerant circulating in the bypass means 13 is greater than the refrigerant flow rate flowing in the thermal storage device 16. Application to motor vehicles.

Description

ASSEMBLY COMPRISING A REFRIGERANT FLUID CIRCUIT AND A HEAT PUMP FLUID CIRCUIT.

The technical sector of the present invention is that of assemblies or systems used to condition a flow of air entering a passenger compartment of a motor vehicle. More particularly, the invention relates to a refrigerant circuit combined with a coolant circuit, wherein the refrigerant circuit is used in heating mode, or heat pump, and incorporating a caloric storage device.

A motor vehicle is conventionally equipped with an air conditioning loop inside which circulates a refrigerant. This loop conventionally comprises a compressor, a condenser, a pressure reducer and an evaporator traversed by the refrigerant. The evaporator is installed in a ventilation, heating and / or general air conditioning system mounted in the passenger compartment of the vehicle to provide the latter with a hot air flow or a cold air flow according to a demand of the vehicle. user of the vehicle. The condenser is conventionally installed on the front of the vehicle to be traversed by the flow of air outside the vehicle. This air conditioning loop can be used in cooling mode or heating mode. In cooling mode, the coolant is sent to the condenser where the coolant is cooled by the outside air flow. Then, the coolant flows to the expander where it undergoes a lowering of its pressure before entering the evaporator. The refrigerant fluid passing through the evaporator is then heated by the flow of air entering the ventilation system, which is correlatively reflected by a cooling of this air flow in order to air condition the passenger compartment of the vehicle. The circuit being a closed loop, the refrigerant then returns to the compressor. In heating mode, the fluid is circulated by the compressor which sends it to the evaporator. The latter then behaves as a condenser, where the coolant is cooled by the air circulating in the ventilation system. This air is heated in contact with the evaporator and thus brings calories to the passenger compartment of the vehicle. After passing through the evaporator, the refrigerant is expanded by a regulator before arriving in the condenser. The outside air flow then heats the refrigerant and the outside air flow is therefore colder after passing through the condenser compared to its temperature before it passes through the condenser. The refrigerant then returns to the compressor.

The improvement of the coefficient of performance of such a loop is desired. The installation of a storage device that exchanges with the refrigerant fluid improves the situation because part of the hot power can be stored and then returned when needed, especially in situations where the exchanger located outside of the vehicle frost, which significantly interfere with the exchange between the refrigerant and the outside air. However, the calorie storage phase in the storage device unbalances the operation of the refrigerant circuit when it operates in heating mode. Indeed, the storage device captures the calories present in the refrigerant. This results in a lowering of the refrigerant temperature which causes an increase in the load on the compressor and correlatively a degradation of the coefficient of performance. The object of the present invention is therefore to solve the disadvantage described above mainly by sharing the circulation of the refrigerant at the storage device and allowing a minor portion of this refrigerant to pass through the thermal storage device, then that the major portion continues its journey towards the external exchanger. The subject of the invention is therefore an assembly comprising a refrigerant circuit and a heat transfer fluid circuit which thermally exchange with each other by means of a refrigerant / heat transfer fluid exchanger, said assembly comprising a storage device. heat exchange which thermally exchange with the coolant and the coolant, wherein the refrigerant circuit comprises a bypass means of the thermal storage device and a refrigerant flow rate management means arranged so that the flow of refrigerant which circulates in the bypass means is greater than the refrigerant flow rate flowing in the thermal storage device. According to a first characteristic of the invention, the coolant circuit comprises at least one coolant circulation pump for transporting the calories stored in the thermal storage device to the coolant / heat transfer fluid exchanger. According to a second characteristic of the invention, the refrigerant circuit comprises at least one compressor, an indoor exchanger, an external exchanger and an evaporator. According to another characteristic of the invention, the compressor is driven by an electric motor integrated in the compressor. According to another characteristic of the invention, the thermal storage device comprises an envelope containing a phase change material, a first beam forming part of the refrigerant circuit and a second beam forming part of the heat transfer fluid circuit. According to yet another characteristic of the invention, the first beam and the second beam exchange, from a thermal point of view, directly with the phase change material. Alternatively or in a complementary manner, the first beam and the second beam exchange, from a thermal point of view, directly with said envelope. Advantageously, the bypass means is formed by a conduit 20 installed in parallel with a first branch of the refrigerant circuit and containing the first beam, and in parallel with a second branch of the refrigerant circuit comprising at least the exchanger inside and the outside exchanger. Advantageously, the coolant flow rate management means 25 is a restriction of a coolant passage section installed in the first branch. Advantageously, the coolant flow rate management means is formed by the first branch which takes the form of a capillary. Alternatively or in a complementary manner, the refrigerant flow rate management means is formed by the first beam which takes the form of a capillary. Finally, note that the bypass means is devoid of heat exchanger.

A first advantage of the invention lies in the ability to capture and store calories in the storage device without disturbing the thermodynamic cycle of the refrigerant circuit. Another advantage lies in the simplicity of the assembly according to the invention.

Indeed, this set is able to operate at least in air conditioning mode, heating mode and defrost mode of the outdoor heat exchanger without the need for many valves. In this regard, it will be noted that the integration of the thermal storage device and the bypass means of this thermal storage device in the refrigerant circuit is done without using a regulating valve since the refrigerant flow rate is imposed by the branch refrigerant circuit which contains the thermal storage device. 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 view of the assembly according to the invention illustrated in an operating state corresponding to a heating mode, - Figure 2 is a schematic view of the assembly according to the invention shown in an operating state corresponding to an air conditioning mode, 20 - Figure 3 is a schematic view of the assembly according to the invention shown in an operating state corresponding to a defrost mode. It should be noted that the figures disclose the invention in detail to implement the invention, said figures can of course be used to better define the invention where appropriate. FIG. 1 illustrates the assembly according to the invention which comprises a refrigerant circuit 1 and a coolant circuit 2. The refrigerant circuit 1 is a closed loop inside which a refrigerant circulates. This cooling fluid is of the subcritical type, for example a compound known by the acronym 1234YF or R134a, but it can also be a supercritical type fluid, such as, for example, carbon dioxide known as reference R744. The refrigerant is circulated by a compressor 3, the function of which is to increase the pressure and the temperature of the refrigerant. This compressor is mechanically driven, in particular by a pulley-belt type mechanism. However, and preferably, this compressor is of the electric type, that is to say a compressor whose compression mechanism is driven by an electric motor integrated in the compressor and thus forming a unitary component. This compressor is for example of the piston type, paddle, spiral and its control may be internal or external, that is to say embedded on the compressor or integrated on a controller separate from the compressor. The compressor 3 comprises an inlet port 4 through which the coolant 1 o arrives and an outlet port 5 through which the refrigerant fluid thus compressed is discharged. This outlet orifice 5 is connected to a first inlet orifice 6 of an internal exchanger 7. This exchanger is described as "interior" in that it is arranged to exchange calories with a flow of air sent inside the passenger compartment of the vehicle. In practice, this indoor exchanger 7 is installed in a housing 8 in which circulates an interior air flow 9 sent into the passenger compartment of a motor vehicle. This internal air flow passes through the exchange body or bundle of the internal exchanger 7 and an exchange body or bundle of an evaporator 10, also installed in the housing 8 upstream of the internal exchanger 7 according to the invention. direction of displacement of the interior air flow 9. It is thus understood that the indoor exchanger 7 is an air / refrigerant heat exchanger, the function of which is to heat the interior air flow 9 before entering the passenger compartment of the motor vehicle. The housing 8 further comprises a mixing flap 63 installed between the evaporator 10 and the indoor exchanger 7 and capable of taking a first position (illustrated in FIGS. 1 and 3) where it forces the interior air flow 9 to passing through the inner exchanger 7, a second position (illustrated in Figure 2) where the mixing flap 63 prevents the passage of the interior air flow 9 in the inner heat exchanger 7, the air flow bypassing then 7. The mixing flap is finally able to take any intermediate positions between the first position and the second position to ensure mixing or mixing of cold air and hot air. This indoor exchanger 7 comprises an outlet orifice 11 connected by a pipe to a first point 12, otherwise called bifurcation point or "Y". The latter is arranged to receive the refrigerant fluid from the indoor exchanger 7, and to separate the flow of refrigerant fluid in two parts. The first point 12 is connected to a bypass means 13 and to a first branch 14 of the refrigerant circuit 1.

The bypass means 13 is formed by a conduit 15 installed in parallel with the first branch 14, the latter channeling the refrigerant fluid to a thermal storage device 16. The first branch 14 comprises a first beam 17 which runs through an internal volume of the device thermal storage, this internal volume being delimited by an envelope 18. This envelope contains a phase change material 60, such as paraffin. Here it is understood that the refrigerating fluid enters the thermal storage device 16 via a first inlet orifice 56 connected on one side to the first branch 14 and on the other to the beam 17. At the opposite end of the first beam 17, there is a first outlet orifice 57 which fluidly connects the first beam 17 to the first branch 14. According to an alternative embodiment of the thermal storage device 16, the first beam 17 exchanges directly with the phase change material 60. It is understood here that the contact between the first beam 17 and this material is direct, the first beam then being embedded in the phase change material. Alternatively, provision can be made for the first beam 17 to exchange directly with the envelope 18, in that the first beam is in direct contact with the envelope 18, for example outside the envelope. An intermediate solution lies in the implantation of the first beam 17 against the envelope 18 and inside thereof. The first bundle 17 then thermally exchanges with the casing 18 via a first face and with the material to be changed by contact against a second face of the first bundle 17. The invention provides a means 61 for managing the refrigerant flow in the first branch 14. The function of this management means 61 is to limit the flow of refrigerant in the first branch 14. Such a limitation imposes a higher refrigerant flow rate in the bypass means 13 of the thermal storage device 16 than in the first branch 14. A 1/5 - 4/5 distribution is particularly suitable for avoiding thermodynamic imbalance in heating mode.

According to an exemplary embodiment of the management means 61, there is provided a restriction 62 of a coolant passage section. This restriction is installed in the first branch 14, for example upstream of the first beam 17. Of course, such a restriction may be placed downstream of the first beam 17, the notions of upstream and downstream being evaluated in the sense of displacement of the fluid in the pipe considered. According to a second exemplary embodiment, the flow management means 61 is implemented by the first branch 14 only, the latter taking the form of a capillary. Alternatively, the capillary may be formed solely by the first beam 17. In an advantageous variant, the capillary is formed by a combination of the first branch 14 with the first beam 17. Capillary means a tube of greater length at 400 mm and with an internal diameter of between 1 mm and 4 mm. The duct 15 is installed in the refrigerant circuit 1 so that this fluid bypasses the first branch 14 containing the first beam 17. The bypass means 13 is devoid of a heat exchanger, the latter then being made solely by a tube of internal diameter between 6 and 10 mm. The first branch 14 and the bypass means 13 meet at a second point 19. The portion of refrigerant fluid from the first bundle 17 constituting the first branch 14 and the portion of refrigerant fluid from the conduit 15 are mixed at the second point 19 and thus reform the entire flow of refrigerant flowing in the inner heat exchanger 7. The second point 19, otherwise called connection point, is fluidly connected to a regulator 20 via a tube or pipe. The regulating member 20 comprises a first expansion member 21 for the refrigerant fluid and a valve 22 installed in parallel with the first expansion member 21. The first expansion member 21 takes the form, for example, of an electronically controlled expansion valve. last obeying a control strategy implemented by a control device (not shown). The valve 22 is a two-way valve with all-or-nothing control. The regulating member 20 for the circulation of the refrigerant fluid has an inlet orifice 23 and an outlet orifice 24 connected to an inlet orifice 25 of an external exchanger 26. This exchanger is described as "external" in this meaning that it is arranged to heat exchange with an outside air flow 27 to the passenger compartment of the vehicle. It is therefore an air / refrigerant heat exchanger. As will be seen later, the external heat exchanger 26 is shaped to operate as an evaporator or as a condenser depending on the operating mode of the assembly according to the invention. This external exchanger 26 is installed at the front of the vehicle so as to benefit from the dynamic air flow when the vehicle is moving. The refrigerant flowing through this external heat exchanger 26 exits the latter through an outlet orifice 28 before reaching a third point 29, where the refrigerant fluid has the ability to separate. This third point 29 supplies the evaporator 10 with refrigerant fluid and / or a coolant / coolant heat exchanger 30. The third point 29 is thus connected on one side to an inlet port 33 of a three-way valve 31, and the other at an inlet 34 of a second expansion member 32, the latter being installed directly upstream of the refrigerant fluid exchanger / heat transfer fluid 30, in the direction of movement of the refrigerant.

The second expansion member 32 comprises an outlet orifice 35 connected to an inlet port 36 of the refrigerant / heat transfer fluid exchanger 30. The refrigerant then passes through a bundle 37 of the refrigerant / heat transfer fluid exchanger 30 and out of the latter through an outlet port 38 to join a fourth point 41, otherwise called connection point.

By passing through the bundle 37 of the refrigerant / coolant heat exchanger 30, the cooling fluid thermally exchanges with the coolant as it circulates in the coolant / coolant heat exchanger 30. The three-way valve 31 comprises the orifice input port 33 connected via a tube at the third point 29, a first outlet port 39 and a second outlet port 40. The first outlet port 39 is fluidly connected to a third expander 42 of the refrigerant, the latter penetrating in this third expansion member 42 via an inlet port 43. The second outlet port 40 of the three-way valve 31 is connected by a tube to the fourth point 41. Once the refrigerant has passed through the third expansion member 42, it enters the exchange body, or beam, of the evaporator 10 through an inlet port 44. The lowering of the pressure of the refrigerated fluid manager operated by the third expansion member 42 causes a cooling of the evaporator so as to lower the temperature of the inner air flow 9 which flows through the evaporator 10. An outlet 45 of the evaporator 10 is as for him connected to the fourth point referenced 41. While the first point 12, the second point 19 and the third point 29 form a fluidic junction between three accesses, the fourth point 41 is different in that it has four accesses. In practice, it is likely to receive the refrigerant by three accesses and returns this combination of refrigerant fluid by a fourth access. The refrigerant / heat transfer fluid exchanger 30 is installed in the refrigerant circuit in parallel, from the fluidic point of view, of the evaporator 10 and of the third expansion member 42. This refrigerant / heat transfer fluid exchanger 30 is also installed in the refrigerant circuit 1 in parallel with the external exchanger 29, the indoor exchanger 7, the thermal storage device 16 and the compressor 3. Once the refrigerant fluid from the refrigerant / heat transfer fluid exchanger 30 and / or the evaporator 10 or the three-way valve 31 has entered the fourth point 41, it comes out to be directed to a battery 46. This refrigerant enters the accumulator 46 through an inlet 47 which is directly connected to the fourth point 41. The accumulator 46 finally includes an outlet 48 through which the coolant exits to return to the compressor 3 by entering da In the refrigerant circuit 1 described above, it is understood that the conduit 15, which forms the bypass means 13, is installed in parallel with the first branch 14, but is also in parallel with a second branch 49 of the refrigerant circuit 1 comprising at least the internal exchanger 7 and the external exchanger 26. More specifically, this second branch 49 also comprises the compressor 3, the fluid exchanger coolant / heat transfer fluid 30 and the evaporator 10.

The components of the refrigerant circuit 1 described above are connected to each other via a tube, a pipe or any means capable of channeling the refrigerant fluid to transport it from a first to a second point. The refrigerant circuit 1 has just been explained in detail and the following will now be attached to the description of the heat transfer fluid circuit 2. This heat transfer fluid circuit 2 forms a closed loop inside which the coolant. The latter is for example a water-based compound containing glycol. This heat transfer fluid circuit forms a loop in which there is at least one pump 50 for circulating the coolant 15 in the loop. Such circulation makes it possible to transport the calories stored in the thermal storage device 16 to the refrigerant / heat transfer fluid exchanger 30, when the defrosting mode is implemented. Such a pump is advantageously driven by electric motor. The heat transfer fluid circuit 2 also comprises the refrigerant / heat transfer fluid exchanger 30. The pump 50 comprises an inlet orifice 51 and an outlet orifice 52, the latter being connected to an inlet pipe 53 of the coolant / heat transfer fluid exchanger 30 by a pipe or any means capable of transporting the coolant. This refrigerant / heat transfer fluid exchanger 30 comprises an outlet pipe 54 fluidly connected to a second inlet orifice 55 of the thermal storage device 16. The heat transfer fluid passes through the thermal storage device 16 while passing through a second beam 58 to exit the thermal storage device 16 through a second outlet port 59. The heat transfer fluid circuit 2 then forms a closed loop when the second outlet port 59 is fluidly connected to the inlet port 51 of the pump 50. According to an alternative embodiment of the thermal storage device 16, the second beam 58 exchanges directly with the phase change material 60. It is understood here that the contact between the second beam 58 and this material is direct, the second beam being then embedded in the phase change material. Alternatively, it can be provided that the second beam 58 exchanges directly with the envelope 18, in that the second beam is directly in contact with the envelope 18, for example outside the envelope. An intermediate solution lies in the implantation of the second beam 58 against the envelope 18 and inside thereof. The second beam 58 then thermally exchanges with the envelope 18 by a first face and with the material to change by contact against a second face of the second beam 58. The assembly according to the invention has just been described and we will now attach to describe the operation of this set according to the modes of use.

In FIGS. 1 to 3, the strong lines used for the refrigerant circuit illustrate a circulation of the refrigerant fluid subjected to a high pressure and a high temperature. The strong dotted lines used for the refrigerant circuit illustrate a circulation of the refrigerant fluid subjected to a low pressure and a low temperature. The fine lines used for the refrigerant circuit illustrate a lack of circulation of the refrigerant in the circuit portion concerned. Similarly, the heat transfer fluid circuit 2 is shown in Figures 1 and 2 in dotted lines, thus illustrating the absence of circulation of the coolant. Such an absence is obtained by stopping the pump 50. On the other hand, the heat transfer fluid circuit 2 is shown in solid line in FIG. 3 to symbolize a circulation of the coolant between the thermal storage device 16 and the refrigerant fluid exchanger. / Heat transfer fluid 30. Figure 1 shows the assembly according to the invention used for example in winter, that is to say in heating mode of the interior air flow 9 sent into the passenger compartment.

Side refrigerant circuit 1, the refrigerant is compressed and circulated by the compressor 3, then passes through the indoor exchanger 7 where the refrigerant yields its calories to the interior air flow 9. The refrigerant continues its course in circulating simultaneously in the thermal storage device 16 and in the bypass means 13. The coolant flow management means 61 passes a minor portion of refrigerant fluid into the first bundle 17 of the thermal storage device, and thus imposes the passage of a major portion, that is to say larger than the minor portion, of the refrigerant in the conduit 15. Such an arrangement allows the phase change material to be charged with calories from the refrigerant, from slow way and without disturbing the thermodynamic cycle. The coolant having circulated in the first branch 14 and the refrigerant fluid 1 circulating in the bypass means 13 combine with the second point 19 and flow to the regulating member 20. The valve 22 is then closed and the first member detent 21 allows a flow of refrigerant to the outer heat exchanger 26, through which it undergoes a lowering of its pressure. The refrigerant, thus expanded, exchanges with the outside air flow 27, which results in a rise in temperature of the refrigerant. In this situation, the external exchanger behaves like an evaporator. The refrigerant then passes into the three-way valve 31, then into the accumulator 46 before returning to the compressor 3. In this variant embodiment, the second expansion member 32 and the third expansion member 42 prohibit the circulation of refrigerant fluid, respectively in the coolant / heat transfer fluid exchanger 30 and in the evaporator 10. Side coolant circuit 2, we see that the first loop 32 is inactive in that the heat transfer fluid does not circulate because the pump 50 is not electrically powered. The mixing flap 63 is placed in its first position in order to force the flow of indoor air through the internal exchanger 7, and correlatively to heat on contact. FIG. 2 illustrates the assembly according to the invention during an operating phase corresponding to a need for cooling of the interior air flow 9. The description below focuses on the differences and reference is made to the description of the Figure 1 for identical elements.

Unlike FIG. 1, the coolant is not expanded by the regulator 20. The first expansion member 21 is closed so that the coolant can not pass therethrough and be relaxed. In contrast, the valve 22 is open and passes the refrigerant without restriction. The latter is then cooled by the flow of outside air 27 during its passage through the external exchanger 26. The refrigerant continues its circulation and passes through the three-way valve 31 to reach the third expansion member 42 This relaxing member 42 reduces the pressure of the refrigerant flowing through it. This refrigerant then enters the evaporator 10 and is heated by the outside air flow 9, which results in a cooling of the interior air flow 9. The refrigerant continues its journey to the accumulator 46 before to reach the inlet port 4 of the compressor 3. With regard to the heat transfer fluid circuit 2, it is noted that it is inactive in that the heat transfer fluid does not circulate, for lack of power supply of the pump 50. The mixing flap 63 is placed in its second position where the interior air flow 9 exchanges with the evaporator 10 but does not exchange with the indoor exchanger 7. The effect of the cooling obtained by the the evaporator 10 is thus not degraded by the internal exchanger 7. FIG. 3 illustrates the assembly according to the invention during an operating phase corresponding to a deicing mode, that is to say a situation where it is detected an ice formation on the outside changer 26, especially when the assembly is used in heating mode and the moisture present in the air stream 27 is outside high. The description below focuses on the differences and reference is made to the description of Figures 1 or 2 for identical elements. The compressor 3 compresses the refrigerant and circulates it through the internal exchanger 7, the bypass means 13 and the thermal storage device 16. The refrigerant continues its course in the circuit 1 and passes through the regulation 20 passing through the valve 22. The refrigerant does not undergo expansion and it then enters the outer heat exchanger 26 in a state of high pressure and high temperature. Such an arrangement makes it possible to defrost the external exchanger very quickly, the ice melting again to allow the circulation of the outside air fluid 27 through the external exchanger 26. The refrigerant fluid then arrives at the third point 29 and bifurcates towards the second expansion member 32. The three-way valve 31 is in the closed position where no circulation of coolant is allowed between the inlet port 33 and the first or second outlet port 39, 40 It is understood from the foregoing that the refrigerant flow path between the outlet port 5 of the compressor 3 and the third point 29 is identical to that described in Figure 2, that is to say the cooling mode. The second expansion member 32 lowers the pressure of the refrigerant flowing therethrough. This refrigerant fluid then enters the refrigerant / heat transfer fluid exchanger 30 in a state of low pressure and low temperature.

After having passed through this refrigerant / heat transfer fluid exchanger 30, the fluid reaches the fourth point 41 to enter the accumulator and finally rejoin the compressor 3. On the coolant circuit 2 side, the defrosting mode results in the Operation of the pump 50. The heat transfer fluid thus flows from the thermal storage device 16 to the refrigerant / heat transfer fluid exchanger 30, the calories being thus transported from the hot point that is the thermal storage device 16 to the heat exchanger Cooling fluid / coolant 30. It will be recalled that during the heating mode that preceded the defrosting mode, the phase change material 60 stored calories. Activation of the defrosting mode makes it possible to transfer these calories to the refrigerant fluid in the state of low pressure and of low temperature, by means of the refrigerant / heat transfer fluid exchanger 30. Such an arrangement makes it possible to produce a point This is necessary for the operation of the thermodynamic cycle when the assembly is operating in defrost mode, while the temperature outside the vehicle is low, for example below 0.degree. The mixing flap 63 is placed in its first position in order to force the flow of indoor air through the internal exchanger 7, and correlatively to heat on contact. Such an arrangement makes it possible to maintain heating of the interior air flow 9 while the assembly is used in defrost mode. Finally, note that the assembly according to the invention is particularly simple to implement while it still allows operation in heating mode, operation in cooling mode and operation in defrost mode. In fact, on the refrigerant circuit side, it can be seen that only one three-way valve is provided. It is the same side coolant circuit where it comprises only the thermal storage device l0 16, the refrigerant fluid exchanger / coolant 30, a heat transfer pump 50 and the pipes connecting these components.

Claims (12)

REVENDICATIONS1. An assembly comprising a refrigerant circuit (1) and a heat transfer fluid circuit (2) which thermally exchange with each other by means of a refrigerant / heat transfer fluid exchanger (30), said assembly comprising a cooling device thermal storage (16) which thermally exchanges with the coolant and with the coolant, wherein the coolant circuit (1) comprises a bypass means (13) of the thermal storage device (16) and a management means ( 61) of refrigerant flow arranged so that the refrigerant flow rate flowing in the bypass means (13) is greater than the coolant flow rate flowing in the thermal storage device (16). 2. The assembly of claim 1, wherein the coolant circuit (2) comprises at least one heat transfer fluid circulating pump (50) for transporting the calories stored in the thermal storage device (16) to the fluid exchanger coolant / coolant (30). 3. Assembly according to one of claims 1 or 2, wherein the refrigerant circuit (1) comprises at least one compressor (3), an indoor exchanger (7), an external exchanger (26) and an evaporator (10). ). 4. The assembly of claim 3, wherein the compressor (3) is driven by an electric motor integrated in the compressor (3). An assembly according to any one of the preceding claims, wherein the thermal storage device (16) comprises an envelope (18) containing a phase change material (60), a first beam (17) forming part of the refrigerant fluid (1) and a second beam (58) forming part of the coolant circuit (2). The assembly of claim 5, wherein the first beam (17) and the second beam (58) exchange directly with the phase change material (60). 7. An assembly according to claims 5 or 6, wherein the first beam (17) and the second beam (58) exchange directly with said envelope (1). 8). 8. An assembly according to any one of claims 5 to 7, wherein the bypass means (13) is formed by a conduit (15) installed in parallel witha first branch (14) of the refrigerant circuit (1) which contains the first beam (17), and in parallel with a second branch (49) of the refrigerant circuit (1) comprising at least the inner heat exchanger (7) and the outer heat exchanger (26). 9. The assembly of claim 8, wherein the refrigerant flow management means (61) is a restriction (62) of a coolant passage section, installed in the first branch (14). 10. The assembly of claim 8, wherein the refrigerant flow management means (61) is formed by the first branch (14) which takes the form of a capillary. 11. An assembly according to any one of claims 8 or 10, wherein the coolant flow management means (61) is formed by the first beam (17) which takes the form of a capillary. 12. An assembly according to any one of the preceding claims, wherein the bypass means (13) is devoid of heat exchanger.