Internal heat exchanger with plates

Abstract

Internal heat exchanger with plates. The invention relates to a heat exchanger (2) with plates (22) of a refrigerant circuit, the heat exchanger (2) comprising at least a plurality of plates (22) stacked on one another in a vertical stacking direction (V), the adjacent plates (22) between them delimiting a plurality of first refrigerant circulation ducts (30) of a low-pressure part (18) of the circuit (1) and a plurality of second refrigerant circulation ducts (32) of a high-pressure part (12) of the circuit (1), at least two of the first circulation ducts (30) being adjacent in the vertical direction (V).

Description

[0001] Internal plate heat exchanger.

[0002] The invention relates to an internal heat exchanger within a refrigerant circuit of a motor vehicle.

[0003] Refrigerant circuits are used to regulate the temperature of an air flow directed towards a motor vehicle passenger compartment and / or to help cool various elements of the vehicle, such as electrical storage devices. For this purpose, the refrigerant circuit incorporates heat exchangers as well as a compressor and an expansion valve which respectively ensure the increase and decrease in pressure of the refrigerant during its circulation within the circuit, so that a high pressure part and a low pressure part can be distinguished in this circuit.

[0004] In such a circuit, the refrigerant entering the compressor must be exclusively in the gaseous state so as not to damage the compressor. To achieve this, it is known to use an accumulation device to recover a persistent liquid fraction of the refrigerant at the outlet of one of the heat exchangers located upstream of the compressor.

[0005] In order to ensure that the refrigerant directed to the compressor is exclusively in the gaseous state, it is also known to integrate an internal heat exchanger which is arranged directly upstream of the compressor and intended to increase the evaporation power of the refrigerant. More particularly, the internal heat exchanger is specific to the refrigerant circuit and is only crossed by the refrigerant, in one direction by the refrigerant circulating in the high-pressure part and in the other direction by the refrigerant circulating in the low-pressure part of the circuit.

[0006] Typically, internal heat exchangers are in the form of two concentric tubes corresponding respectively to one and the other of the low pressure and high pressure parts of the circuit, with a wall common to each of the two concentric tubes, and the heat exchange necessary to ensure the evaporation of the refrigerant from the low pressure part of the circuit, prior to the entry of the refrigerant into the compressor, is done through the wall common to the two concentric tubes. However, a disadvantage of such an internal heat exchanger in the form of concentric tubes lies on the one hand in the significant bulk that it generates within the vehicle and on the other hand in the efficiency that can be improved due to a significant pressure drop in the tube crossed by the refrigerant at low pressure, thus limiting the evaporation performance of the refrigerant.

[0007] The invention therefore proposes to solve these problems by designing an internal plate heat exchanger capable of withstanding the high pressure conditions of the refrigerant circuit while limiting the pressure drop of the refrigerant in the low pressure circuit, thus guaranteeing optimal evaporation power of the refrigerant at low pressure. The particular structure of the internal heat exchanger in the form of plates makes it possible in particular to guarantee space savings compared to the structures of the prior art in the form of a concentric tube. By these effects, the operation of the refrigerant circuit is thus generally improved.

[0008] The invention relates more particularly to a plate heat exchanger of a refrigerant circuit, the heat exchanger comprising a plurality of plates stacked on top of each other in a vertical stacking direction, the adjacent plates delimiting between them a plurality of first channels for circulation of the refrigerant of a low pressure part of the circuit and a plurality of second channels for circulation of the refrigerant of a high pressure part of the circuit,at least a portion of the plurality of plates of the heat exchanger comprising a plurality of openings, some of which form a first inlet manifold and others of which form a first outlet manifold for the low-pressure refrigerant fluid communicating with the first circulation channels and some of which form a second inlet manifold and others of which form a second outlet manifold for the high-pressure refrigerant fluid communicating with the second circulation channels, the heat exchanger being characterized in that at least two of the first circulation channels are adjacent in the vertical stacking direction.,

[0009] The heat exchanger is a plate exchanger formed by a stack of plates configured to delimit between them refrigerant circulation channels, the plates being linked to each other so as to make the circulation channels that they participate in delimiting in fluid communication or not with the collectors which extend across the plates along the stacking direction. An appropriate spacing between two adjacent plates generates a refrigerant circulation channel and the fact that this channel opens onto a collector associated with a low pressure portion of the circuit or onto a collector associated with a high pressure portion of the circuit makes it possible to qualify this channel either as a first low pressure circulation channel or as a second high pressure circulation channel.

[0010] The heat exchanger here is an internal heat exchanger arranged within a refrigerant circuit upstream of a refrigerant circuit compressor, so as to be crossed only by the refrigerant, in two distinct directions and at different pressures and temperatures, so that the heat exchange takes place between the refrigerant in a first state and the refrigerant in a second state. The internal heat exchanger has, among other things, the function of increasing the evaporation power of the low-pressure refrigerant before it enters the compressor. The internal heat exchanger therefore allows the low-pressure refrigerant to carry out a heat exchange with the high-pressure refrigerant by recovering a portion of the latter's calories, ensuring the passage to the gaseous state of a persistent liquid fraction in the low-pressure refrigerant.

[0011] Advantage is then taken of the particular arrangement of the circulation channels within the internal plate heat exchanger according to the invention insofar as it is possible to provide a number of first circulation channels, associated with the circulation of the low-pressure refrigerant, which is greater than the number of second circulation channels, associated with the circulation of the high-pressure refrigerant, which makes it possible to limit the pressure drop of the low-pressure refrigerant when it circulates in the heat exchanger, thus making it possible to improve the heat exchanges with the high-pressure refrigerant, in the context of a plate exchanger that is less bulky than a concentric tube exchanger. This improves the evaporation power of the low-pressure refrigerant in the internal heat exchanger.

[0012] According to a characteristic of the invention, the circulation channels delimited by the adjacent plates of the plurality of plates are arranged so that a second circulation channel extends on either side, in the vertical direction, of the assembly formed by the at least two first adjacent circulation channels.

[0013] According to a feature of the invention, the first circulation channels are arranged in sets of two adjacent first circulation channels along the vertical direction and partially delimited respectively by the same plate. In other words, at least one of the plates of the plurality of plates delimits two adjacent first circulation channels. In this context, three adjacent plates are necessary to delimit two adjacent first circulation channels, the plate arranged in the center of the stack of these three adjacent plates, or central plate, being common to the two adjacent first circulation channels.

[0014] According to a characteristic of the invention, each of the assemblies is separated from another assembly by a single second circulation channel in the vertical direction. All of the first circulation channels can thus be arranged in assemblies of two adjacent first circulation channels in the vertical direction, separated by a single second circulation channel, so that there tends to be a distribution of the circulation channels with a number of first circulation channels, associated with the circulation of the low-pressure refrigerant, which is greater than or equal to twice the number of second circulation channels, associated with the circulation of the high-pressure refrigerant.

[0015] According to a characteristic of the invention, each of the plates comprises peripheral portions surrounding each of the openings, a peripheral portion of a plate being able to be made integral with the peripheral portion of an adjacent plate to isolate the circulation channel delimited between these adjacent plates from the collector formed by the corresponding openings.

[0016] According to a characteristic of the invention, at the level of the low-pressure refrigerant fluid collectors, the plates are distributed into primary plates, with a flat peripheral portion which extends in a plane substantially perpendicular to the vertical stacking direction, and secondary plates whose peripheral portion is deformed to come into contact with the peripheral portion of a primary plate, the internal plate heat exchanger being configured so that the plurality of plates comprises two successive primary plates at regular intervals.

[0017] According to a characteristic of the invention, the edges of the peripheral portions participating in delimiting a collector formed by a plurality of openings have a thickness varying from one edge to the other along the vertical stacking direction.

[0018] According to a characteristic of the invention, each of the plates comprises at least one exchange surface against which the refrigerant circulates and a raised edge, the plurality of plates being stacked such that each of the raised edges of each of the plates are in contact with each other and that each of the exchange surfaces is at a non-zero distance so as to form the circulation channels.

[0019] According to a characteristic of the invention, at least one of the exchange surfaces of one of the plates of the plurality of plates comprises a boss.

[0020] An irregular profile is understood to mean a profile that extends outside a main extension plane of the plate. For example, the irregular profile may be formed by deformation of the exchange surfaces of the plates in such a way as to disturb the circulation of the refrigerant against the upper and lower faces of the plates. Such a disturbance of the circulation of the refrigerant makes it possible to increase the heat exchanges between the low-pressure refrigerant and the high-pressure refrigerant circulating in their respective circulation channels.

[0021] The invention also relates to a refrigerant circuit comprising at least one heat exchanger according to any one of the preceding characteristics, the refrigerant circuit comprising a high pressure part and a low pressure part, the heat exchanger being fluidically arranged in the circuit such that it allows a heat exchange between the refrigerant circulating in gaseous form in the low pressure part with the refrigerant circulating in liquid form in the high pressure part.

[0022] According to a characteristic of the invention, the first circulation channels of the heat exchanger are connected to the low pressure part of the circuit by means of a first and a second connection blocks and the second circulation channels of the heat exchanger are connected to the high pressure part of the circuit by means of a third and a fourth connection blocks of the heat exchanger.

[0023] Other characteristics, details and advantages of the invention will emerge more clearly on reading the description given below for information purposes in relation to drawings in which:

[0024] [Fig i] is a schematic view of part of a refrigerant circuit;

[0025] [Fig 2] is a sectional view of a heat exchanger of the refrigerant circuit;

[0026] [Fig 3] is a perspective view of a stack of plates forming the heat exchanger of Figure 2;

[0027] [Fig 4] is a schematic representation of a detail of Figure 2.

[0028] It should first be noted that while the figures set out the invention in detail for its implementation, these figures can of course be used to better define the invention, where appropriate. It should also be noted that these figures only set out examples of embodiments of the invention. Finally, the same references designate the same elements in all the figures.

[0029] In Figure 1 is illustrated a refrigerant circuit 1 comprising at least one heat exchanger 2 according to the invention, here an internal heat exchanger 2. The refrigerant circuit 1 also comprises at least one compressor 4, a condenser 6, an evaporator 8 as well as an accumulation device 10. The circuit

[0030] I of refrigerant fluid makes it possible to heat and / or cool a heat transfer fluid 15, 21 separate from the circuit 1 and for example directed towards a passenger compartment of a vehicle, or towards an electrical storage device of an electric or hybrid vehicle.

[0031] It should be considered that the refrigerant fluid circuit detailed in the remainder of the description is only an example of an embodiment, and that said circuit may include more elements which will not be described here.

[0032] The compressor 4 illustrated schematically in Figure 1 makes it possible to compress the refrigerant fluid in order to increase its pressure, and consequently its temperature. Thus, at the outlet of the compressor 4, the high-pressure refrigerant fluid is in the gaseous state and has a high temperature, that is to say higher than its inlet temperature in said compressor 4. It is then understood that at the outlet of the compressor 4, the refrigerant fluid circulates in a high-pressure part 12 of the refrigerant circuit 1.

[0033] A first pipe 14a extends between the compressor 4 and the condenser 6, which allows an exchange of calories between a heat transfer fluid 15 passing through it and the refrigerant fluid at high temperature and high pressure, which transfers these calories to said heat transfer fluid 15. At the outlet of the condenser 6, the refrigerant fluid remains at high pressure but has a lower temperature than at the inlet of the condenser, so that it leaves in a two-phase or completely liquid state.

[0034] At the outlet of the condenser 6, the refrigerant is directed into a second pipe 14b which extends between said condenser 6 and the internal heat exchanger 2 mentioned previously. The internal heat exchanger 2 is configured so as to be traversed by the refrigerant in two opposite directions, the refrigerant being at high pressure in the first direction and at low pressure in the second direction. The refrigerant of the high-pressure part 12 of the refrigerant circuit 1 can exchange calories with the refrigerant circulating in a low-pressure part 18 of the refrigerant circuit 1. This heat transfer makes it possible to improve the performance of the thermodynamic cycle implemented in the refrigerant circuit 1. The structure of the internal heat exchanger 2 will be detailed later in the description.

[0035] At the end of its passage through the internal heat exchanger 2, the refrigerant circulates in a third pipe 14c which connects said internal heat exchanger 2 to the evaporator 8. More particularly, the third pipe 14c comprises at least one expansion valve 20 which makes it possible to lower the pressure and the evaporation point of the high-pressure refrigerant before it enters the evaporator 8. It is understood that it is from the expansion valve 20 that one passes from the high-pressure part 12 of the refrigerant circuit 1 to the low-pressure part 18 mentioned previously.

[0036] At the outlet of the expansion valve 20, the refrigerant fluid is at low pressure and circulates within the evaporator 8 in order to exchange calories with a heat transfer fluid 21, for example intended to cool an electrical storage device not shown, passing through said evaporator 8. More particularly, this heat transfer fluid passing through the evaporator 8 transfers its calories to the refrigerant fluid circulating in the evaporator 8, which thus evaporates. Thus, it is understood that within the evaporator 8, the refrigerant fluid evaporates under the effect of the capture of the calories of the heat transfer fluid 21, the expansion valve 20 having lowered its evaporation point. In this way, at the outlet of the evaporator 8, the refrigerant fluid is mainly in the gaseous state.

[0037] At the outlet of the evaporator 8, the refrigerant fluid is directed in a fourth pipe 14 d towards the accumulation device 10, here for example an accumulation bottle. The accumulation device 10 has the function of collecting a persistent liquid fraction of the refrigerant fluid at the outlet of the evaporator 8. Such a passage in the accumulation device 10 is necessary prior to the passage of the refrigerant fluid into the compressor 4 which can only accept the refrigerant fluid in the gaseous state.

[0038] At the outlet of the accumulation device 10, the refrigerant fluid passes through a fifth pipe 14e which directs it towards the internal heat exchanger 2 mentioned above, in order to exchange calories with the refrigerant fluid of the high pressure part 12 of the refrigerant circuit 1 mentioned above. Such a passage through the internal heat exchanger 2 makes it possible to guarantee that the refrigerant fluid at the outlet of said internal heat exchanger 2 is exclusively in the gaseous state, prior to its entry into the compressor 4.

[0039] The heat exchanger according to the invention is in this context configured to guarantee optimal efficiency of the heat exchange and in particular of the evaporation of the refrigerant fluid when it circulates in the low pressure part, so as not to damage the compressor 4 arranged downstream of the latter, such damage being able to reduce the operating efficiency of the refrigerant circuit 1.

[0040] Thus, the internal heat exchanger 2 according to the invention will now be described in more detail, in particular with reference to FIGS. 2 to 4.

[0041] The internal heat exchanger 2 is a plate exchanger comprising plates 22 stacked one above the other and which is configured so that refrigerant circulates in conduits formed between two adjacent plates, the plates being configured to form both low pressure conduits 30, namely conduits connected only to the low pressure part 18 of the circuit, and high pressure conduits 32, namely conduits connected only to the high pressure part 12 of the circuit. According to the invention, the plates 22 are configured and connected to each other so that the number of low pressure conduits 30 is greater than the number of high pressure conduits 32, and in particular so that the number of low pressure conduits is greater than or equal to twice the number of high pressure conduits.

[0042] More particularly, the internal heat exchanger 2 according to the invention comprises a plurality of plates 22 stacked on top of each other in a vertical stacking direction V. Each of these plates 22 has a bathtub shape with an exchange surface 24 surrounded peripherally by a raised edge 26. The plates 22 are stacked such that the raised edge 26 of each of the plates 22 is in contact with at least one other raised edge 26 and such that the exchange surface 24 of each of the plates 22 is at a non-zero distance, in the vertical stacking direction V, from the exchange surfaces 24 of the adjacent plates. Circulation channels 28 for the refrigerant fluid are thus formed between two adjacent plates, each of these channels being configured to fluidically communicate with a fluid inlet and a fluid outlet connected to one of the high-pressure or low-pressure parts of the circuit.More particularly, the adjacent plates 22 delimit between them a plurality of first circulation channels 30 for the refrigerant fluid of the low pressure part 18 of the circuit and a plurality of second circulation channels 32 for the refrigerant fluid of the high pressure part 12 of the circuit.

[0043] At least a portion of the plurality of plates 22 of the heat exchanger 2 each comprises a plurality of openings 34, some of which are arranged vertically one above the other to form a plurality of collectors, as can be seen in particular in FIG. 3. The arrangement of the openings 34 thus makes it possible to define, on the one hand, a first inlet collector 36a and a first outlet collector 36b for the low-pressure refrigerant fluid, intended to communicate fluidically with each of the first circulation channels 30, and, on the other hand, a second inlet collector 38a and a second outlet collector 38b for the high-pressure refrigerant fluid, intended to communicate fluidically with each of the second circulation channels 32. Each of the collectors 36a, 36b, 38a, 38b is formed by an alignment of openings and extends vertically through the plurality of plates 22.

[0044] A collector 36a, 36b, 38a, 38b is advantageously provided in each of the corners of the plate heat exchanger, as is more particularly visible in FIG. 3, it being understood that the two inlet collectors 36a, 38a may be diagonally opposite, without a different arrangement departing from the context of the invention, since as mentioned the number of first circulation channels within the exchanger is greater than the number of second circulation channels. The arrangement with diagonally opposite inlet collectors, without being limiting of the invention, makes it possible to generate within the internal heat exchanger 2 a cross circulation of the refrigerant present in the first circulation channels 30 at low pressure and the refrigerant present in the second circulation channels 32 at high pressure, thus helping to improve the quality of the heat exchanges.Such circulation in alternating directions is notably visible in figure 4, where the direction of circulation of the refrigerant fluid is represented by arrows, and more particularly first arrows S1 for a first direction of circulation within the first circulation channels 30 and by second arrows S2 for a second direction of circulation within the second circulation channels 32.

[0045] Furthermore, a first end plate 40 and a second end plate 42 are defined, each extending at a vertical end of the stack of plates 22. The first end plate 40 is then devoid of openings 34 so that it participates in vertically closing a volume of the heat exchanger 2. Furthermore, according to the illustrated example of the invention, the second end plate 42 carries four connection blocks 44a, 44b, 44c, 44d, shown schematically in FIG. 1 and intended to be arranged opposite each of the collectors 36a, 36b, 38a, 38b formed by the openings 34 of the plates 22. In other words, each of the connection blocks 44a, 44b, 44c, 44d is arranged on the second end plate 42 covering the openings 34 formed in the second end plate 42.

[0046] It is then understood that the connection blocks 44a, 44b, 44c, 44b provide the fluid connection between the pipes 14b, 14c, 14e, 14f of the refrigerant circuit 1 described above and the circulation channels 30, 32 delimited by the plates 22. More particularly, a first connection block 44a fluidly connects the fifth pipe 14e to the first circulation channels 30 via the first inlet manifold 36a, a second connection block 44b connects the first circulation channels 30 to the sixth pipe 14b via the first outlet manifold 36b, a third connection block 44c fluidly connects the second pipe 14b to the second circulation channels 32 via the second inlet manifold 38a and a fourth connection block 44d fluidly connects the second circulation channels 32 to the third pipe 14c via the second outlet manifold. 38b.

[0047] As mentioned previously, according to the invention, the plates 22 are configured so that at least two of the first circulation channels 30 are adjacent in the vertical direction V. In the remainder of the description, two adjacent first circulation channels 30 will be referred to as a set 46.

[0048] Depending on its positioning in the stack of plates 22 forming the heat exchanger according to the invention, this set of first adjacent circulation channels 30 is delimited vertically by the first end plate 40, the second end plate 42, or by a second circulation channel 32. Where appropriate, at the heart of the heat exchanger, two second circulation channels 32 extend on either side of the set 46 formed by two first adjacent circulation channels 30, in the vertical direction V.In other words, according to the invention, there is at least one sequence formed by the successive stacking of a second circulation channel 32 and the set 46 of the two adjacent first circulation channels 30, and this sequence can be reproduced vertically so that a second circulation channel 32 is found between a first set 46 of two adjacent first circulation channels 30 and a second set 46 of two adjacent first circulation channels 30.

[0049] According to an example of the invention, all of the first circulation channels 30 of the heat exchanger 2 are arranged in sets 46 as described previously, each of the sets 46 being separated from another set 46 by a single second circulation channel 32 along the vertical direction V. In this way, the circulation channels 28 are distributed so that a number of first circulation channels 30 is greater than the number of second circulation channels 32, with the number of first circulation channels 30 which may be greater than or equal to twice the number of second circulation channels 32.

[0050] Advantage is taken of such an arrangement of the circulation channels 30, 32 in the heat exchanger 2 in that it makes it possible to increase the passage section of the low-pressure refrigerant fluid in the heat exchanger 2 relative to the passage section of the high-pressure refrigerant fluid, making it possible to reduce the pressure drop in the part of the low-pressure circuit and to increase the quality of the heat exchange 2 between the low-pressure refrigerant fluid and the high-pressure refrigerant fluid.

[0051] The plates being stacked one above the other and participating in delimiting the circulation channels 28 between them, it is understood that within the plurality of plates 22, a central plate 221 participates in delimiting two first adjacent circulation channels 30 forming a set 46 and that the two neighboring plates 222, 223 of this central plate 221 each participate in delimiting on the one hand one of the first circulation channels 30 of the set 46 and on the other hand a second circulation channel 32 adjacent to this set 46.

[0052] As can be seen in particular in the detail of FIG. 4, these two neighboring plates 222, 223 have different configurations to allow the fluid communication of the first circulation channels 30 and the second circulation channels 32 with the corresponding collectors to be blocked or authorized.

[0053] An upper face 48 and a lower face 50 of each of the exchange surfaces 24 of each of the plates 22 are defined, opposite one another in the vertical direction V, the upper face 48 here being the face directed towards the second end plate 42 and the lower face 50 here being the face directed towards the first end plate 40.

[0054] With the exception of the end plates 40, 42, each of the faces 48, 50 of a plate 22 participates in delimiting a distinct circulation channel 30, 32. More particularly, for a central plate 221, the upper face 48 and the lower face 50 each participate in delimiting one of the first adjacent circulation channels 30 forming an assembly 46 as previously mentioned. And for a neighboring plate 222, 223 of this central plate, one of its upper 48 or lower 50 faces also participates in delimiting one of the first adjacent circulation channels 30 of the assembly 46 while the other face 48, 50 participates in delimiting a second circulation channel 32.

[0055] Peripheral portions 52 of the exchange surface of each of the plates 22 are also defined, shown in dotted lines in FIG. 3 and surrounding each of the openings 34 provided in the exchange surface. It is understood that at the level of a given collector, formed by the alignment of openings 34 made within the plurality of plates 22, the peripheral portions 52 of two adjacent plates can be made integral with each other to prevent the fluid circulating between these two plates from opening into the collector or, on the contrary, that they can extend at a distance from each other so that the fluid circulating between these two plates can communicate with the collector.

[0056] For the collectors 36a, 36b allowing the entry and exit of fluid in the low pressure circuit, in order to form an assembly as mentioned previously of two first adjacent circulation channels 30, the peripheral portion 52 of one of the neighboring plates 222 of the central plate 221 is deformed, opposite the central plate, to be in contact with another plate and to form, in particular by brazing, a sealed zone preventing fluid communication between a second circulation channel 32 and the corresponding collector. The peripheral portion 52 of the other neighboring plate 223 has a configuration similar to that of the peripheral portion of the central plate 221, here a substantially planar configuration.

[0057] It is thus possible to distinguish, in the plurality of plates illustrated in FIG. 4, primary plates 22a, with a peripheral portion 52 in the same plane as the main elongation plane of the exchange surface 24, and secondary plates 22b whose peripheral portion 52 is deformed to come into contact with the peripheral portion of a primary plate 22a. And it is notable according to the invention that the internal plate heat exchanger comprises two successive primary plates 22a at regular intervals.

[0058] In this context, it is also notable that the thickness of the plate edges 220 participating in delimiting a collector 36a, 36b associated with the low-pressure circuit varies from one edge to the other, due in particular to the junction at regular intervals of two adjacent peripheral portions to block the fluid communication between a second circulation channel 32 and this collector. More particularly, a plate edge 220 formed by the peripheral portion 52 of the central plate 221 has a first thickness ei, substantially equal to the average thickness of each of the plates of the exchanger, and the plate edge 53 adjacent to this peripheral portion 52 of the central plate 221 has a second thickness e2, substantially equal to twice the average thickness of each of the plates of the exchanger, since it is formed by the junction of the peripheral portions of two adjacent plates.

[0059] According to the example of the invention illustrated, at least one of the exchange surfaces 24 of one of the plates 22 of the plurality of plates 22 comprises a boss 60. The boss 60, visible as an example in FIG. 4, forms a projection of the lower face 50 of the corresponding plate, tending to move closer to the exchange surface of the adjacent plate opposite this lower face 50. The passage section of the refrigerant fluid is thus locally reduced and this results in a disturbance of the circulation of the refrigerant fluid within the circulation channel delimited by the lower face 50 equipped with the boss and the upper face 48 of the adjacent plate. Such a disturbance of the circulation of the refrigerant fluid in the circulation channels makes it possible to increase the heat exchanges between the low-pressure refrigerant fluid and the high-pressure refrigerant fluid circulating in their respective circulation channels 30, 32.

[0060] The invention as just described achieves the aim it set for itself by proposing an internal plate heat exchanger, the plates of which are more particularly configured and arranged relative to each other to allow an internal heat exchange in a refrigerant circuit which does not have any pressure loss at the low pressure part of this circuit. It should however be noted that the invention cannot be limited to the means and configurations exclusively described and illustrated, and also applies to any equivalent means or configurations and to any combination of such means or configurations.

Claims

DEMANDS 1. Plate heat exchanger (2) (22) of a refrigerant circuit (1), the heat exchanger (2) comprising at least a plurality of plates (22) stacked one on top of the other in a vertical stacking direction (V), the adjacent plates (22) delimiting between them a plurality of first circulation channels (30) of the refrigerant of a low pressure part (18) of the circuit (1) and a plurality of second circulation channels (32) of the refrigerant of a high pressure part (12) of the circuit (1),at least a portion of the plurality of plates (22) of the heat exchanger (2) comprising a plurality of openings (34) among which some form a first inlet manifold (36a) and others form a first outlet manifold (36b) of the low-pressure refrigerant communicating with the first circulation channels (30) and among which some form a second inlet manifold (38a) and others form a second outlet manifold (38b) of the high-pressure refrigerant communicating with the second circulation channels (32), the heat exchanger (2) being characterized in that at least two of the first circulation channels (30) are adjacent along the vertical stacking direction (V).

2. Heat exchanger (2) according to claim 1, wherein the number of first circulation channels (30), respectively delimited by two adjacent plates of the plurality of plates (22) and communicating with the low pressure part (18) of the circuit, is greater than the number of second circulation channels (32), respectively delimited by two adjacent plates of the plurality of plates (22) and communicating with the high pressure part (12) of the circuit (1).

3. Heat exchanger (2) according to any one of the preceding claims, wherein the circulation channels delimited by the adjacent plates of the plurality of plates (22) are arranged so that a second circulation channel (32) extends on either side, along the vertical direction (V), of the assembly formed by the at least two first adjacent circulation channels (30).

4. Heat exchanger (2) according to any one of the preceding claims, wherein the first circulation channels (30) are arranged in sets (46) of two first circulation channels (30) adjacent along the vertical direction (V) and partially delimited respectively by the same plate (22).

5. Heat exchanger (2) according to the preceding claim, in which each of the assemblies (46) is separated from another assembly by a single second circulation channel (32) along the vertical direction (V).

6. Heat exchanger (2) according to any one of the preceding claims, in which each of the plates (22) has peripheral portions (52) surrounding each of the openings (34), a peripheral portion (52) of a plate (22) being able to be made integral with the peripheral portion (52) of an adjacent plate to isolate the circulation channel delimited between these adjacent plates from the collector formed by the corresponding openings.

7. Heat exchanger (2) according to any one of the preceding claims, wherein, at the level of the low pressure refrigerant manifolds, the plates (22) are distributed into primary plates (22a), with a flat peripheral portion (52) extending in a plane substantially perpendicular to the vertical stacking direction, and secondary plates (22b) whose peripheral portion (52) is deformed to come into contact with the peripheral portion (52) of a primary plate (22a), the internal plate heat exchanger being configured so that the plurality of plates comprises at regular intervals two successive primary plates (22a).

8. Heat exchanger (2) according to the preceding claim, in which the edges of the peripheral portions (52) participating in delimiting a collector formed by a plurality of openings (34) have a thickness varying from one edge to the other along the vertical stacking direction (V).

9. Heat exchanger (2) according to any one of the preceding claims, in which each of the plates (22) comprises at least one exchange surface (24) against which the refrigerant circulates and a raised edge (26), the plurality of plates (22) being stacked such that each of the raised edges (26) of each of the plates (22) are in contact with each other and each of the exchange surfaces (24) is at a non-zero distance so as to form the circulation channels (30, 32). io. Refrigerant circuit (1) comprising at least one heat exchanger (2) according to any one of the preceding claims, the refrigerant circuit (1) comprising a high pressure part (12) and a low pressure part (18), the heat exchanger (2) being fluidly arranged in the circuit (1) such that it allows heat exchange between the refrigerant circulating mainly in gaseous form in the low pressure part (18) with the refrigerant circulating mainly in liquid form in the high pressure part (12).

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