WO2021116564A1

WO2021116564A1 - Reversible thermal-management device

Info

Publication number: WO2021116564A1
Application number: PCT/FR2020/052249
Authority: WO
Inventors: Mohamed Yahia; Bertrand Nicolas; Jin-ming LIU
Original assignee: Valeo Systemes Thermiques
Priority date: 2019-12-12
Filing date: 2020-12-02
Publication date: 2021-06-17
Also published as: FR3104493B1; FR3104493A1

Abstract

Reversible thermal-management device (1) for a motor vehicle, said thermal-management device (1) comprising a refrigerant fluid circuit, and comprising: • a main loop (A) comprising, in succession, a compressor (3), an internal condenser (5), a thermostatic expansion device (7) and an external evaporator/condenser (9), • a first tapped-off branch (B), • a second tapped-off branch (C), • a third tapped-off branch (D) comprising at least a heat exchanger (11, 13), • a first redirection device (X) for redirecting the refrigerant fluid coming from the compressor (3) towards the internal condenser (5) or towards the first tapped-off branch (B), • a second redirection device (Y) redirecting the refrigerant fluid coming from the thermostatic expansion device (7) towards the at least one heat exchanger (11, 13) of the third tapped-off branch (D) or towards the evaporator/condenser (9), • an internal heat exchanger (15) arranged on the main loop (A) and configured to allow exchanges of heat energy between the high-pressure refrigerant fluid upstream of the thermostatic expansion device (7) and the low-pressure refrigerant fluid downstream of the at least one heat exchanger (11, 13).

Description

INVERSIBLE THERMAL MANAGEMENT DEVICE

[1] The invention relates to the field of motor vehicles and more particularly to an invertible thermal management device for a motor vehicle. [2] Current motor vehicles increasingly include a thermal management device. Generally, in a “conventional” thermal management device, a refrigerant fluid circulates in an air conditioning circuit and passes successively through a compressor, a first heat exchanger, called a condenser, placed in contact with a flow of air outside the motor vehicle. to release heat, an expansion device and a second heat exchanger, called an evaporator, placed in contact with an air flow inside the motor vehicle to cool it.

[3] There are also more complex air conditioning circuit architectures which make it possible to obtain an invertible thermal management device, ie it can use a heat pump operating mode in which it is able to absorb heat energy in the outside air at the first heat exchanger, then called evapo / condenser, and return it to the passenger compartment in particular by means of a third dedicated heat exchanger.

[4] This is possible in particular by using a dedicated internal condenser arranged in the internal air flow and allowing to heat said internal air flow.

[5] The thermal management device can also include one or more heat exchangers, generally arranged in parallel with the evaporator, in order for example to cool elements such as batteries in a hybrid or electric vehicle. [6] The thermal management device thus generally comprises a dedicated expansion device upstream of each heat exchanger. Such an architecture is not always suitable because it requires as many expansion devices as there are heat exchangers capable of playing the role of evaporator and therefore it is expensive. [7] One of the aims of the present invention is therefore to at least partially remedy the drawbacks of the prior art and to provide an improved and less expensive thermal management device. [8] The present invention therefore relates to an invertible thermal management device of a motor vehicle, said thermal management device comprising a refrigerant circuit in which a refrigerant fluid circulates and comprising: a main loop successively comprising a compressor, a internal condenser, a thermostatic expansion valve and an external evapo / condenser,

• a first branch branch connecting a first connection point arranged on the main loop downstream of the compressor, between the compressor and the thermostatic expansion valve, to a second connection point arranged on the main loop upstream of G evapo / external condenser, between said external evapo / condenser and the thermostatic expansion valve,

• a second bypass branch connecting a third connection point arranged on the main loop downstream of G evapo / external condenser, between said evapo / external condenser and the compressor, to a fourth connection point arranged on the main loop upstream of the thermostatic expansion valve, between the first connection point and said thermostatic expansion valve, a third branch branch connecting a fifth connection point arranged on the main loop downstream of the thermostatic expansion valve, between said thermostatic expansion valve and the second connection point, to a sixth connection point arranged on the main loop upstream of the compressor, between said compressor and the third connection point, said third bypass branch comprising at least one heat exchanger,

• a first device for redirecting the refrigerant from the compressor to the internal condenser or to the first bypass branch, · a refrigerant shut-off valve placed on the main loop between the third and the sixth connection point,

• a first non-return valve arranged on the second bypass branch so as to block the refrigerant fluid coming from the fourth connection point, • a second device for redirecting the refrigerant from the thermostatic expansion valve to at least one heat exchanger in the third branch branch or to the evapo / condenser,

• an internal heat exchanger arranged on the main loop and configured to allow heat energy exchanges between the high pressure refrigerant upstream of the thermostatic expansion valve and the low pressure refrigerant from the sixth connection point.

[9] According to one aspect of the invention, the refrigerant circuit further comprises a second non-return valve arranged on the main loop between the first and the fourth connection point so as to block the refrigerant from said fourth point. connection.

[10] According to another aspect of the invention, the thermostatic expansion valve comprises a thermostatic bulb disposed upstream of the compressor between the low pressure side of the internal heat exchanger and said compressor. [1 l] According to another aspect of the invention, the internal condenser is arranged on the main loop downstream of the first connection point, between the first and the fourth connection point.

[12] According to another aspect of the invention, the second device for redirection of the refrigerant fluid coming from the thermostatic expansion valve comprises: a first shut-off valve arranged on the main loop upstream of the evapo / condenser, between the second connection point and the fifth connection point,

• at least one other shut-off valve arranged on the third bypass branch upstream of the at least one heat exchanger, between the fifth connection point and the at least one heat exchanger.

[13] According to another aspect of the invention, the refrigerant circuit comprises a third non-return valve arranged on the main loop between the first shut-off valve of the second device for redirection of the refrigerant from the thermostatic expansion valve and the second connection point so as to block the refrigerant fluid coming from the second connection point.

[14] According to another aspect of the invention, the third branch branch comprises an internal evaporator and in that the invertible thermal management device comprises a fourth branch branch comprising a cooler, said fourth bypass branch connecting a seventh connection point arranged on the third bypass branch downstream of the fifth connection point, between said fifth connection point and the internal evaporator, to an eighth connection point arranged on the third branch branch upstream of the sixth connection point, between said sixth connection point and the internal evaporator, the second device for redirecting the refrigerant fluid from the thermostatic expansion valve being configured to redirect the fluid to the evapo / condenser or to the internal evaporator and / or cooler. [15] According to another aspect of the invention, the second device for redirection of the refrigerant fluid coming from the thermostatic expansion valve comprises:

• a second stop valve arranged on the third bypass branch upstream of the internal evaporator, between said internal evaporator and the seventh connection point, and · a third stop valve placed on the fourth bypass branch upstream of the cooler, between said cooler and the seventh connection point.

[16] According to another aspect of the invention, the first non-return valve is also a pressure regulating valve configured to allow the passage of the refrigerant fluid in the second branch branch between the third and the fourth point of connection to a first determined pressure.

[17] According to another aspect of the invention, the second non-return valve is also a pressure regulating valve configured to allow the passage of the refrigerant fluid from the internal condenser to the fourth connection point at a second determined pressure.

[18] Other characteristics and advantages of the invention will emerge more clearly on reading the following description, given by way of illustrative and non-limiting example, and the appended drawings, among which:

[19] Figure 1 is a schematic representation of an invertible thermal management device,

[20] Figure 2a is a schematic representation of the invertible thermal management device of Figure 1 according to a first cooling mode,

[21] FIG. 2b is a schematic representation of the invertible thermal management device of FIG. 1 according to a second cooling mode, [22] Figure 3a is a schematic representation of the invertible thermal management device of Figure 1 according to a first heat pump mode,

[23] FIG. 3b is a schematic representation of the invertible thermal management device of FIG. 1 according to a second heat pump mode, [24] FIG. 4 is a schematic representation of the invertible thermal management device of FIG. 1 according to a dehumidification mode,

[25] FIG. 5 is a schematic representation of the invertible thermal management device of FIG. 1 according to a defrost mode.

[26] In the various figures, identical elements bear the same reference numbers.

[27] The following realizations are examples. Although the description refers to one or more embodiments, this does not necessarily mean that each reference relates to the same embodiment, or that the characteristics apply only to one embodiment. Simple features of different embodiments can also be combined and / or interchanged to provide other embodiments.

[28] In the present description, it is possible to index certain elements or parameters, such as for example first element or second element as well as first parameter and second parameter or even first criterion and second criterion, and so on. In this case, it is a simple indexing to differentiate and name similar elements or parameters or criteria, but not identical. This indexing does not imply a priority of one element, parameter or criterion over another and such names can easily be interchanged without departing from the scope of the present description. [29] In the present description, by "placed upstream" is meant that one element is placed before another with respect to the direction of flow of a fluid. Conversely, by "placed downstream" is meant that one element is placed after another with respect to the direction of flow of the fluid.

[30] Figure 1 shows an invertible thermal management device 1 of a motor vehicle. This invertible thermal management device 1 comprises a refrigerant fluid circuit in which a refrigerant fluid circulates. In the representation of Figure 1 as well as in the following figures, the refrigerant circuit is in particular divided into a main loop A to which are connected bypass branches B, C, D and E. The choice of this main loop A is an arbitrary choice used to make it easier to understand the different branches and the position of the different elements with respect to each other. The main loop A is shown in solid lines and the bypass branches B, C, D and E in dotted lines. [3 l] The main loop A successively comprises a compressor 3, an internal condenser 5, a thermostatic expansion valve 7 and an evapo / external condenser 9. Here, “internal” means that the element is intended to be crossed by a flow. internal air (not shown) which is itself intended to reach the passenger compartment of the motor vehicle. By “external” is meant that the element is intended to be passed through by an external air flow (not shown) coming from outside the motor vehicle.

[32] The refrigerant fluid is intended in particular to circulate in the compressor 3, the internal condenser 5, the thermostatic expansion valve 7 and G evapo / external condenser 9 in an operating mode called a heat pump which will be detailed later in the description. It is this direction of circulation of the refrigerant that is taken into consideration arbitrarily to facilitate understanding and to define the terms "upstream" and "downstream".

[33] The invertible thermal management device 1 also comprises a first bypass branch B connecting a first connection point 51 to a second connection point 52. The first connection point 51 is arranged on the main loop A downstream of the compressor 3, between said compressor 3 and the thermostatic expansion valve 7. The second connection point 52 is for its part disposed on the main loop A upstream of G evapo / external condenser 9, between said evapo / external condenser 9 and the thermostatic expansion valve 7.

[34] The invertible thermal management device 1 also comprises a second branch branch C connecting a third connection point 53 to a fourth connection point 54. The third connection point 53 is arranged on the main loop A downstream of the 'evapo / external condenser 9, between said evapo / external condenser 9 and compressor 3. The fourth connection point 54 is for its part disposed on the main loop A upstream of the thermostatic expansion valve 7, between the first connection point 51 and said thermostatic expansion valve 7. According to the embodiment illustrated in FIG. 1, the fourth connection point 54 is disposed downstream of the internal condenser 5. [35] The invertible thermal management device 1 finally comprises a third branch branch D connecting a fifth connection point 55 to a sixth connection point 56. The fifth connection point 55 is arranged on the main loop A downstream of the regulator thermostatic 7, between said thermostatic expansion valve 7 and the second connection point 52. The sixth connection point 56 is for its part disposed on the main loop A upstream of the compressor 3, between said compressor 3 and the third connection point 53. This third branch branch D comprises in particular at least one heat exchanger 11, 13. [36] The internal condenser 5 can, according to a first embodiment illustrated in FIG. 1, be arranged downstream of the first connection point. 51, between the first 51 and the fourth 54 connection point. This positioning allows the refrigerant fluid to circulate in the internal condenser 5 only when it is necessary to exchange heat energy with the internal air flow passing through it, such as for example in a heat pump mode.

[37] According to a second embodiment (not shown), the internal condenser 5 can be arranged upstream of the first connection point 51. In this second embodiment, the refrigerant fluid circulates in the internal condenser 5 in all the modes. Operating. If in one of these operating modes it is not necessary to exchange heat energy with the internal air flow passing through the internal condenser 5, said internal air flow must be stopped or diverted so that 'it does not pass through the internal condenser. The first embodiment is thus preferred because it is simpler to implement.

[38] The invertible thermal management device 1 also comprises a first device for X redirection of the refrigerant coming from the compressor 3 to the fourth connection point 54 or to the first branch branch B. This first X redirection device makes it possible to choose whether the refrigerant from the compressor 3 is redirected to the fourth connection point 54 or to the first bypass branch B depending on the operating mode chosen.

[39] This first X redirection device may in particular consist of a first 21 and a second 22 shut-off valve. The first shut-off valve 21 is arranged on the main loop A upstream of the fourth connection point 54, between the first 51 and said fourth connection point 54. The second stop valve 22 is arranged on the first bypass branch B. Depending on the opening or closing of these stop valves 21-22, it is thus possible to control the direction of the refrigerant fluid. An alternative can be a three-way valve arranged at the first connection point.

[40] The invertible thermal management device 1 also comprises various elements for controlling the circulation of the refrigerant fluid allowing operation according to different operating modes.

[41] The invertible thermal management device 1 thus comprises an internal heat exchanger 15 arranged on the main loop A and configured to allow exchanges of heat energy between the high pressure refrigerant fluid upstream of the thermostatic expansion valve 7 and the low pressure refrigerant fluid coming from the sixth connection point 56. The high pressure side of the internal heat exchanger 15 is in particular arranged between the fourth connection point 54 and the thermostatic expansion valve 7. The low pressure side of the exchanger internal heat 15 is placed between the sixth connection point 56 and the compressor 3.

[42] The second bypass branch C thus comprises a first non-return valve 24 arranged so as to block the refrigerant from the fourth connection point 54. This first non-return valve 24 may be a non-return valve. According to a variant, this first non-return valve 24 can in particular be a pressure regulation valve configured to allow the passage of the refrigerant fluid in the second bypass branch C between the third 53 and the fourth 54 connection point at a determined first pressure. This first determined pressure is in particular useful for allowing the high-pressure refrigerant fluid to undergo optimum sub-cooling when it passes through the internal heat exchanger 15, in particular in a cooling mode as described later in the description. This allows an improvement in the performance coefficient of the invertible thermal management device 1. This first determined pressure can in particular be chosen from test tables as a function of various parameters such as the outside temperature, the target temperature within the passenger compartment. , as well as the pressure and the temperature of the refrigerant fluid at different positions in the invertible thermal management device 1. [43] The main loop A comprises a shut-off valve 23 for the refrigerant fluid arranged between the third 53 and the sixth 56 connection point.

[44] The main loop A can also include a second non-return valve 25 arranged between the first 51 and the fourth 54 connection point so as to block the refrigerant from the fourth connection point 54, more precisely the second branch of bypass C.

This second non-return valve 25 can be a non-return valve. According to a variant, this second non-return valve 25 can also be a pressure regulation valve configured to allow the passage of the refrigerant fluid from the first connection point 51 to the fourth connection point 54 at a second determined pressure. This second determined pressure is in particular useful for allowing the high-pressure refrigerant fluid to undergo optimum sub-cooling when it passes through the internal heat exchanger 15, in particular in a heat pump mode as described later in the description. This makes it possible to improve the coefficient of performance of the invertible thermal management device 1 while limiting the superheating of the low-pressure refrigerant fluid which enters the compressor 3. This second determined pressure can in particular be chosen from test tables as a function of various parameters such as the exterior temperature, the target temperature within the passenger compartment, as well as the pressure and the temperature of the coolant at different positions in the invertible thermal management device 1.

[45] The invertible thermal management device 1 further comprises a second device for redirecting the refrigerant fluid Y from the thermostatic expansion valve 7 to at least one heat exchanger 11, 13 of the third branch branch D or to the evapo / condenser 9. This second device for redirecting the refrigerant fluid Y coming from the thermostatic expansion valve 7 thus makes it possible to redirect the refrigerant fluid which has passed through the thermostatic expansion valve. [46] The second device Y for redirection of the refrigerant from the thermostatic expansion valve 7 may in particular include:

• a first stop valve 31 arranged on the main loop A upstream of the evapo / condenser 9, between the fifth connection point 55 and the second non-return valve 25, • at least one other shut-off valve 32, 33 disposed on the third bypass branch D upstream of the at least one heat exchanger 11, 13, between the fifth connection point 55 and the at least one heat exchanger. heat 11, 13. [47] The main loop A can also optionally include a third non-return valve 26 arranged between the first shut-off valve 31 of the second device Y for redirection of the refrigerant from the thermostatic expansion valve 7 and the second connection point 52 so as to block the refrigerant fluid coming from the second connection point 52. This third non-return valve 26 may be a non-return valve. This third non-return valve 26 makes it possible to prevent a reflux of refrigerant from the second connection point 52, for example in a cooling mode towards the first non-return valve 31. The tightness of this first valve of stopping is then improved and it is possible to use a first stop valve 31 with less expensive single flow.

[48] The thermostatic expansion valve 7 may in particular include a thermostatic bulb 70 disposed upstream of the compressor 3 between the low pressure side of the internal heat exchanger 15 and said compressor 3.

The use of a thermostatic expansion valve 7 reduces the production costs of the invertible thermal management device 1.

[49] In the example illustrated in Figure 1, the invertible thermal management device 1 comprises two heat exchangers 11, 13 on the third branch branch D. More specifically, these two heat exchangers 11, 13 are connected in parallel to each other. Thus, the third branch branch D comprises an internal evaporator 11 and a cooler 13. This cooler 13 is arranged on a fourth branch branch E connecting a seventh connection point 57 to an eighth connection point 58. The seventh connection point 57 is disposed on the third branch branch D downstream of the fifth connection point 55, between said fifth connection point 55 and the internal evaporator 11. The eighth connection point

58 is for its part disposed on the third branch branch D upstream of the sixth connection point 56, between said sixth connection point 56 and G internal evaporator 11. [50] In this example, the second device for redirecting the refrigerant fluid Y coming from the thermostatic expansion valve 7 is configured to redirect the fluid to the evapo / condenser 9 or to the internal evaporator 11 and / or the cooler 13. For this, the second device Y for redirection of the refrigerant from the thermostatic expansion valve 7 may in particular include:

• a second shut-off valve 32 arranged on the third bypass branch D upstream of the internal evaporator 11, between said internal evaporator 11 and the seventh connection point 57, and a third shut-off valve 33 arranged on the fourth branch branch

E upstream of the cooler 13, between said cooler 13 and the seventh connection point 57.

[51] It should be noted that the invention is not limited to an example with one or two heat exchangers 11, 13 and that it is possible to have a greater number of heat exchangers 11, 13 on the third branch branch D. The second device for redirection 7 of the refrigerant fluid coming from the thermostatic expansion valve 7 can be configured to control the distribution of the refrigerant fluid for each of these heat exchangers 11, 13.

[52] The evaporator According to another aspect of the invention, 11 may be more particularly disposed in the internal air flow to the passenger compartment in order to cool the latter. The cooler 13 can, for example, be a cooler intended to cool elements such as the batteries of an electric or hybrid motor vehicle. The cooler 13 can also be, for example, another evaporator placed in an internal air flow, for example in the case of air conditioning with several zones.

[53] The invertible thermal management device 1 can also include a phase separation device (not shown) such as for example an accumulator. This accumulator can for example be placed on the main loop A upstream of the low pressure part of the internal heat exchanger 15. More precisely, this accumulator can be placed between the sixth connection point 56 and the internal heat exchanger. 15.

[54] Instead of an accumulator, the invertible thermal management device 1 can include a desiccant bottle (not shown). This desiccant bottle can be placed downstream of the internal condenser 5. More precisely, the bottle desiccant can be placed between the fourth connection point 54 and the high pressure part of the internal heat exchanger 15.

[55] Figures 2a to 6 show the invertible thermal management device 1 according to different operating modes. In these Figures 2a to 6, only the active elements are shown. The direction of circulation of the refrigerant fluid is represented by arrows.

G5611) First cooling mode:

[57] FIG. 2a shows the invertible thermal management device 1 according to a first so-called cooling mode of operation. [58] In this first mode of cooling, the refrigerant first passes through compressor 3 where it undergoes an increase in pressure. The high pressure refrigerant then passes through the first bypass branch B and joins the evapo / condenser 9. The high pressure refrigerant transfers heat energy to the external air flow and passes into the second bypass branch. C. The high pressure refrigerant then passes through the internal heat exchanger 15 where it undergoes subcooling. The high pressure refrigerant then passes through the thermostatic expansion valve 7 at which it experiences a loss of pressure. The low-pressure refrigerant then passes through the third bypass branch D and passes into the internal evaporator 11 where it recovers heat energy from the internal air flow. The low-pressure refrigerant passes through the internal heat exchanger 15 where it overheats and then returns to the compressor 3.

[59] To make this path possible, the first device for redirecting the refrigerant fluid X from the compressor 3 redirects the refrigerant to the first bypass branch B. For this, its first stop valve 21 is closed and its second stop valve 22 is open.

[60] In this first cooling mode, the refrigerant fluid leaving the thermostatic expansion valve 7 passes only into the internal evaporator 11. The second device for redirecting the refrigerant fluid from the thermostatic expansion valve 7 redirects the refrigerant fluid only to the internal evaporator 11. For this, its first shut-off valve 31 is closed. Its second stop valve 32 is open and its third stop valve 33 is closed. The stop valve 23 is for its part closed. [61] In this first cooling mode, the invertible thermal management device 1 is used to cool exclusively the internal air flow passing through the internal evaporator 11 in order to cool the passenger compartment. Second cooling mode:

[63] FIG. 2b shows the invertible thermal management device 1 according to a second cooling mode.

[64] This second cooling mode is identical to the first cooling mode with the difference that at the outlet of the thermostatic expansion valve 7 the refrigerant fluid passes into the third branch branch D and into the fourth branch branch E to cross both the cooler 13 and the internal evaporator 11. At the cooler 13 and the internal evaporator 11, the coolant recovers heat energy.

[65] In this second cooling mode, the refrigerant fluid leaving the thermostatic expansion valve 7 passes both into the cooler 13 and into the internal evaporator 11. The second device Y for redirecting the refrigerant coming from the thermostatic expansion valve 7 redirects the refrigerant simultaneously to the cooler 13 and the internal evaporator 11. For this, its first stop valve 31 is closed. His second 32 and third 33 shut-off valves are open. The stop valve 23 is closed. [66] In this second cooling mode, the invertible thermal management device 1 is used to cool both the internal air flow and the element associated with the cooler 13, for example the batteries of a hybrid motor vehicle or electric.

[67] The invertible thermal management device 1 can also operate according to a third cooling mode (not shown) in which the refrigerant at the outlet of the thermostatic expansion valve 7 passes only into the cooler 13. The second Y redirection device of the fluid refrigerant coming from the thermostatic expansion valve 7 redirects the refrigerant fluid only to the cooler 13. For this, its first stop valve 31 is closed. Its second stop valve 32 is closed and its third stop valve 33 is open. The stop valve 23 is for its part closed. In this third cooling mode, the invertible thermal management device 1 is used to cool exclusively the element associated with the cooler 13, for example the batteries of a hybrid or electric motor vehicle. First heat pump mode:

[69] Figure 3a shows the invertible thermal management device 1 according to a first mode of operation called heat pump.

[70] In this first heat pump mode, the refrigerant first passes through compressor 3 where it undergoes an increase in pressure. The high pressure refrigerant then passes into the internal condenser 5 which is crossed by the internal air flow. The high-pressure refrigerant transfers heat energy to the internal air flow and then passes to the internal heat exchanger 15 where it undergoes sub-cooling. The refrigerant then passes into the thermostatic expansion valve 7 at which it experiences a loss of pressure. The low pressure refrigerant then passes to the evapo / condenser 9 where it recovers heat energy in the external air flow. The low-pressure refrigerant then passes into the internal heat exchanger 15 where it overheats and then returns to the compressor 3.

[71] In this first heat pump mode, the refrigerant circulates only in the main loop A.

[72] To make this journey possible, the first device for redirecting the refrigerant fluid X from the compressor 3 redirects the refrigerant to the thermostatic expansion valve 7. For this, its first shut-off valve 21 is open and its second valve stop 22 is closed.

[73] The second device for redirecting the refrigerant fluid Y coming from the thermostatic expansion valve 7 redirects the refrigerant fluid to the evapo / condenser 9. For this, its first stop valve 31 is open and its second 32 and third 33 shut-off valves are closed. The shut-off valve 23 is open.

[74] This first heat pump mode makes it possible to heat the internal air flow and thus heat the passenger compartment of the motor vehicle.

G7514) Second heat pump mode: [76] FIG. 3b shows the invertible thermal management device 1 according to a second heat pump mode.

[77] This second heat pump mode is identical to the first heat pump mode except that at the outlet of the thermostatic expansion valve 7 the refrigerant also passes into the third bypass branch D and into the fourth branch E branch to cross both the cooler 13 and the internal evaporator 11 in parallel with the evapo / condenser 9. At the cooler 13 and the internal evaporator 11, the refrigerant recovers energy calorific. [78] In this second heat pump mode, the refrigerant fluid leaving the thermostatic expansion valve 7 passes both into the cooler 13 and into the internal evaporator 11. The second device for redirecting Y the refrigerant coming from the thermostatic expansion valve static 7 redirects the refrigerant simultaneously to the cooler 13 and the internal evaporator 11. For this, its first stop valve 31 is open. His second 32 and third

33 shut-off valves are open.

[79] In this second heat pump mode, the invertible thermal management device 1 is used to heat the internal air flow by absorbing heat energy at the evapo / condenser 9 but also by recovering water. calorific energy at the level of the element associated with the cooler 13, for example the batteries of a hybrid or electric motor vehicle and at the level of the internal evaporator 11. This is particularly useful for rapid heating of the internal air flow at the level of the internal condenser 5 with an external temperature of the order of 5 ° C. [80] It is also possible to imagine a similar heat pump mode in which the invertible thermal management device 1 allows heat energy recovery at the level of the single cooler 13 in addition to the evapo / condenser 9.

G81151 Dehumidification mode: [82] FIG. 4 shows the invertible thermal management device 1 according to an operating mode called dehumidification.

[83] In this dehumidification mode, the refrigerant first passes through the compressor 3 where it undergoes an increase in pressure. The high pressure refrigerant then passes into the internal condenser 5 which is crossed by the internal air flow. The high pressure refrigerant fluid transfers heat energy to the internal air flow and then passes into the internal heat exchanger 15 where it undergoes sub-cooling. The refrigerant then passes into the thermostatic expansion valve 7 at which it experiences a loss of pressure. [84] A portion of the low-pressure refrigerant then passes into the evapo / condenser 9 at which it recovers heat energy in the external air flow.

[85] Another part of the low pressure refrigerant fluid passes through the internal evaporator 11 where it recovers energy from the internal air flow.

[86] The two low-pressure refrigerant fluids meet at the sixth connection point 56. The low-pressure refrigerant then passes into the internal heat exchanger 15 where it overheats and then returns to the compressor 3.

[87] In order for this trip to be possible, the first device for redirection X of the refrigerant fluid coming from the compressor 3 redirects the refrigerant fluid to the thermostatic expansion valve 7. For this, its first stop valve 21 is open and its second valve stop 22 is closed. [88] The second device for redirecting the refrigerant fluid Y coming from the thermostatic expansion valve 7 redirects the refrigerant fluid to the evapo / condenser 9 and to the internal evaporator 11. For this, its first 31 and second 32 valves stop 31 are open and its third stop valve 33 is closed. The shut-off valve 23 is open. [89] Generally, the internal condenser 5 is arranged downstream of the internal evaporator 11 in the direction of circulation of the internal air flow. Thus, in this dehumidification mode, the internal air flow undergoes cooling and heating which leads to its dehumidification.

[90] It is possible to imagine another mode of dehumidification in the case where the internal condenser 5 is arranged upstream of the first connection point 51.

In this case, it is possible for the high pressure refrigerant fluid to flow successively in the internal condenser 5 at which it heats the internal air flow. The high pressure refrigerant then takes the first branch B branch and joins the evapo / condenser 9 where it gives heat energy to the external air flow. The high-pressure refrigerant then passes through the second bypass branch C and the internal heat exchanger 15 where it undergoes sub-cooling. The refrigerant then passes through the thermostatic expansion valve 7 where it undergoes a loss of pressure. The low pressure refrigerant then passes through the internal evaporator 11 at which it cools the internal air flow. The low-pressure refrigerant then passes through the internal heat exchanger 15 where it undergoes overheating before returning to the compressor 3. The circulation of the refrigerant is done here in series between the various heat exchangers. G91161 De-icing mode:

[92] FIG. 5 shows the invertible thermal management device 1 according to a so-called defrost operating mode.

[93] In this defrost mode, the refrigerant first passes through compressor 3 where it undergoes an increase in pressure. The high pressure refrigerant then passes into the first branch branch

B and joins the evapo / condenser 9. The high pressure refrigerant fluid passes through the evapo / condenser 9 and gives up heat energy not to the external air flow but to the evapo / condenser 9 itself in order to to defrost it. The external air flow is therefore blocked so that it does not pass through the evapo / condenser 9, for example by closing the flaps of a front face shutter device. The high-pressure refrigerant then passes through the internal heat exchanger 15 where it undergoes sub-cooling via the second bypass branch C. The high-pressure refrigerant then passes into the thermostatic expansion valve 7 at which it undergoes a loss of pressure. The low-pressure refrigerant then passes into the third branch branch D and passes into the cooler 13 where it recovers heat energy from the element linked to it. The low-pressure refrigerant fluid passes through the internal heat exchanger 15 where it overheats and then returns to compressor 3. [94] To make this path possible, the first device X for redirecting the refrigerant from the compressor 3 redirects the refrigerant to the first bypass branch B. For this, its first stop valve 21 is closed and its second stop valve 22 is open.

[95] In this defrosting mode, the refrigerant fluid leaving the thermostatic expansion valve 7 passes only into the cooler 13. The second device for redirecting the refrigerant fluid from the thermostatic expansion valve 7 redirects the refrigerant only to the cooler. 13. For this, its first stop valve 31 is closed. Its second valve stop 32 is closed and its third stop valve 33 is open. The stop valve 23 is for its part closed.

[96] This defrost mode makes it possible to defrost the evapo / condenser 9 of the frost that may form during the heat pump mode by recovering heat energy at the level of the cooler 13. This is particularly effective during a journey at high speed, for example on a motorway during which the shutters of a front face shutter device are closed.

[97] Thus, it is clear that, due to its architecture, the invertible thermal management device 1 is economical while retaining a wide variety of operating modes. In addition, the invertible thermal management device 1 is also effective and efficient.

Claims

1. Reversible thermal management device (1) of a motor vehicle, said thermal management device (1) comprising a refrigerant circuit in which a refrigerant fluid circulates and comprising: a main loop (A) successively comprising a compressor (3), an internal condenser (5), a thermostatic expansion valve (7) and an external evapo / condenser (9),

• a first bypass branch (B) connecting a first connection point (51) arranged on the main loop (A) downstream of the compressor (3), between the compressor (3) and the thermostatic expansion valve (7), to a second connection point (52) arranged on the main loop (A) upstream of G evapo / external condenser (9), between said evapo / external condenser (9) and the thermostatic expansion valve (7),

• a second branch branch (C) connecting a third connection point (53) arranged on the main loop (A) downstream of

G evapo / external condenser (9), between said evapo / external condenser (9) and the compressor (3), at a fourth connection point (54) arranged on the main loop (A) upstream of the thermostatic expansion valve (7) , between the first connection point (51) and said thermostatic expansion valve (7), a third branch branch (D) connecting a fifth connection point (55) arranged on the main loop (A) downstream of the thermostatic expansion valve (7), between said thermostatic expansion valve (7) and the second connection point (52), at a sixth connection point (56) arranged on the main loop (A) upstream of the compressor (3), between said compressor (3) and the third connection point (53), said third bypass branch (D) comprising at least one heat exchanger (11, 13),

• a first device for redirection (X) of the refrigerant fluid coming from the compressor (3) to the internal condenser (5) or to the first bypass branch (B),

• a refrigerant shut-off valve (23) arranged on the main loop (A) between the third (53) and the sixth (56) connection point, • a first non-return valve (24) arranged on the second bypass branch (C) so as to block the refrigerant from the fourth connection point (54),

• a second device for redirection (Y) of the refrigerant from the thermostatic expansion valve (7) to at least one heat exchanger (11, 13) of the third bypass branch (D) or to the evapo / condenser (9),

• an internal heat exchanger (15) arranged on the main loop (A) and configured to allow exchanges of heat energy between the high pressure refrigerant fluid upstream of the thermostatic expansion valve (7) and the low pressure refrigerant fluid in from the sixth connection point (56).

2. Reversible thermal management device (1) according to the preceding claim, characterized in that the refrigerant circuit further comprises a second non-return valve (25) disposed on the main loop (A) between the first (51) and the fourth (54) connection point so as to block the refrigerant from said fourth connection point (54).

3. Reversible thermal management device (1) according to any one of the preceding claims, characterized in that the thermostatic expansion valve (7) comprises a thermostatic bulb (70) arranged upstream of the compressor (3) between the low pressure side of the internal heat exchanger (15) and said compressor (3).

4. Reversible thermal management device (1) according to any one of the preceding claims, characterized in that the internal condenser (5) is arranged on the main loop (A) downstream of the first connection point (51), between the first (51) and the fourth (54) connection point.

5. Reversible thermal management device (1) according to any one of the preceding claims, characterized in that the second redirection device (Y) of the refrigerant from the thermostatic expansion valve (7) comprises:

• a first shut-off valve (31) placed on the main loop (A) upstream of the evapo / condenser (9), between the second connection point (52) and the fifth connection point (55), • at least one other shut-off valve (32, 33) arranged on the third bypass branch (D) upstream of the at least one heat exchanger (11, 13), between the fifth connection point (55) and the at least one heat exchanger (11, 13). 6. Reversible thermal management device (1) according to the preceding claim, characterized in that the refrigerant circuit comprises a third non-return valve (26) arranged on the main loop (A) between the first shut-off valve ( 31) of the second device for redirection (Y) of the refrigerant fluid coming from the thermostatic expansion valve (7) and the second connection point (52) so as to block the refrigerant fluid coming from the second connection point (52).

7. An invertible thermal management device (1) according to any one of the preceding claims, characterized in that the third bypass branch (D) comprises an internal evaporator (11) and in that the invertible thermal management device (1 ) has a fourth branch branch

(E) comprising a cooler (15), said fourth bypass branch (E) connecting a seventh connection point (57) disposed on the third bypass branch (D) downstream of the fifth connection point (55), between said fifth connection point (55) and the internal evaporator (11), to an eighth connection point (58) arranged on the third bypass branch (D) upstream of the sixth connection point (56), between said sixth point connection (56) and the internal evaporator (11), the second redirection device (Y) of the refrigerant fluid coming from the thermostatic expansion valve (7) being configured to redirect the fluid to the evapo / condenser (9) or to the internal evaporator (11) and / or the cooler

(15).

8. Reversible thermal management device (1) according to claims 4 and 5, characterized in that the second redirection device (Y) of the refrigerant from the thermostatic expansion valve (7) comprises: a second shut-off valve (32) arranged on the third bypass branch (D) upstream of G internal evaporator (11), between said internal evaporator (11) and the seventh connection point (57), and • a third shut-off valve (33) disposed on the fourth branch branch (E) upstream of the cooler (13), between said cooler (13) and the seventh connection point (57).

9. Reversible thermal management device (1) according to any one of the preceding claims, characterized in that the first non-return valve

(24) is also a pressure regulating valve configured to allow the passage of the refrigerant fluid in the second bypass branch (C) between the third (53) and the fourth (54) connection point at a determined first pressure. 10. Reversible thermal management device (1) according to claim 2 or according to any one of claims 3 to 9 in combination with claim 2, characterized in that the second non-return valve (25) is also a control valve of pressure configured to allow the passage of the refrigerant fluid from the internal condenser (5) to the fourth connection point (54) at a second determined pressure.