HEATING, VENTILATION AND / OR AIR CONDITIONING SYSTEM FOR A MOTOR VEHICLE

Description

[0001] The present invention relates to a heating, ventilation and / or air conditioning device for a motor vehicle as well as on a motor vehicle comprising such a heating, ventilation and / or air conditioning device.

[0002] A motor vehicle is commonly equipped with a ventilation, heating, and / or air conditioning system to regulate the aerothermal parameters of an airflow distributed into the vehicle's passenger compartment. The system generally comprises a housing delimited by partitions in which openings are provided, including at least one air intake and at least one air outlet.

[0003] As is known, the housing contains a blower to circulate the airflow from the air intake to the air outlet. The housing also contains heat treatment components to heat and / or cool the airflow before it is distributed inside the passenger compartment. For example, these heat treatment components might include an evaporator, which cools and dehumidifies the airflow passing through it, and a radiator, possibly combined with an additional radiator, which heats the airflow passing through it.

[0004] The heating, ventilation, and / or air conditioning (HVAC) system can be supplied with either outside air (also called fresh air) or recirculated air, meaning air from inside the vehicle. Typically, a blower is used to circulate the airflow. This airflow can be fresh air from outside the vehicle, recirculated air from inside the vehicle, or a mixture of both.

[0005] It is important to be able to separate the airflows (outside air - recirculated air), particularly during the passage, from the airflows through the heating, ventilation and / or air conditioning system, according to the needs of the vehicle occupants, or in other words during the thermal conditioning of the airflows.

[0006] Indeed, since the recirculated air is already at a temperature close to the target temperature, it is possible to quickly reach the user's desired temperature. However, recirculated air is more humid than air coming from outside the vehicle, so if the recirculated air is directed near the windshield via vents located in front of the driver or front passenger, for example, or directly onto the windshield, the humidity in the recirculated air condenses on the windshield and creates fogging.

[0007] The exhaust system includes several ducts distributing airflow to nozzles opening in different areas of the passenger compartment. These include the defrost outlet, which directs airflow to the defrost nozzle to demist the windshield; the ventilation duct, which directs airflow to the side / center ventilation nozzles to cool / heat the vehicle's occupants; and the footwell duct, which directs airflow to the footwell nozzles to cool / heat the feet of the front / rear passengers. There may also be a separate duct dedicated to the rear passengers.

[0008] A known solution, such as that described in document WO 2019 / 044302 A1, involves thermally conditioning the outside airflow and directing it into the passenger compartment near or directly onto the windshield, and thermally conditioning the recirculated airflow for distribution into the passenger compartment away from the windshield, at other air vents, such as those located at the driver's or front passenger's feet. This is a dual-layer operating mode.

[0009] However, in these known systems, it is observed that an excessive amount of hot air, having passed through the radiator, is directed towards the ventilation outlet, resulting in the airflow temperature at the foot outlet being equal to the airflow temperature at the ventilation outlet. This leads to a decrease in thermal comfort, where it is generally preferable to have a higher temperature for the feet than for the ventilation.

[0010] The aim of the invention is to remedy this drawback. To this end, the invention proposes a heating, ventilation and / or air conditioning device for a motor vehicle comprising a housing, said housing comprising: a first flow duct for a first airflow; a second flow duct for a second airflow; a partition partition arranged within the casing so as to separate the first flow duct from the second flow duct; a first heat exchanger arranged in the first flow duct and in the second flow duct, said heat exchanger being common to both flow ducts; a second heat exchanger arranged downstream, with respect to the flow of an airflow, from the first heat exchanger and arranged within the second flow duct; a first damper arranged downstream of the second heat exchanger; the first flap being able to pivot between two extreme positions, a first extreme position where said flap comes to rest against the partition wall and / or the second heat exchanger and a second extreme position where said flap comes to rest against a wall of the casing; characterized in that the casing includes an airflow guide wall arranged within the first flow duct downstream of the first heat exchanger and directing the first airflow towards the first flap; and in that the casing includes a space between the airflow guide wall and the first flap such that the first flap is not able to come to rest against the airflow guide wall, and in which the first flap pivots in an intermediate position located between the two extreme positions with the airflow guide wall extending in one direction and the first flap comprising a door extending in one direction;in said intermediate position, said door being in line with the wall guiding an airflow.

[0011] The invention thus ensures that the airflow is guided towards the flap, which is designed to direct the airflow towards the footwell outlet. However, the space created between the airflow guide wall and the flap allows for the maintenance of normal operating modes, supplying warm air to the ventilation and / or defrost outlets while simultaneously supplying warm air to the footwell outlet.

[0012] Preferably, the device includes a third heat exchanger arranged upstream of the first heat exchanger with respect to the flow of an air stream, the third heat exchanger being arranged in the first flow duct and in the second flow duct, said heat exchanger being common to both flow ducts.

[0013] Preferably, in said intermediate position the space between the end of the airflow guide wall and the end of the first flap is between 5 and 25 mm, preferably between 10 and 15 mm.

[0014] Preferably, the first flap is suitable for closing an inlet of an outlet duct when said flap is positioned in the second extreme position.

[0015] Preferably, the first airflow duct and the second airflow duct each include a bypass path of the first heat exchanger, the bypass paths being arranged on either side of the first heat exchanger.

[0016] Preferably, a second flap, in particular a butterfly-type flap, is arranged within the first airflow duct and a third flap, in particular a sliding door type, is arranged within the second airflow duct, said flaps being arranged between the first and third heat exchangers so as to direct each respective airflow through the corresponding bypass path and / or through the first heat exchanger.

[0017] Preferably, the first flow duct of an airflow also includes a fourth flap, in particular of butterfly type, arranged within the corresponding bypass path.

[0018] Preferably, the housing includes a screen element arranged at one end of the shutter, said screen element being of a shape complementary to the stroke of the shutter and extending at least in part over a portion of the stroke of the shutter.

[0019] Preferably, the flap is of the butterfly type and the screen element is arranged in the upstream part, relative to the flow of an airflow, of the housing relative to the flap.

[0020] Preferably, the case includes a second screen element arranged at the other end of the flap.

[0021] Preferably, the first screen element extends over at least 10% of the shutter travel, preferably between 20% and 50% of the shutter travel.

[0022] Preferably, the second screen element extends over at least 5% of the shutter travel, preferably between 10% and 30% of the shutter travel.

[0023] The invention also relates to a motor vehicle comprising a heating, ventilation and / or air conditioning device as described above, in which the duct corresponds to the foot outlet and is configured to supply air to the foot area of ​​the passenger compartment.

[0024] It is understood that the above features and configurations are in no way limiting. Other features, details, and advantages of the invention will become clearer upon reading the detailed description given below, and several illustrative and non-limiting examples of embodiments given with reference to the accompanying schematic drawings, in which: There Figure 1 [Fig. 1] ] illustrates a cross-section in profile view of the heating, ventilation and / or air conditioning device according to the invention in one operating mode; The Figure 2 [Fig. 2] ] illustrates a detailed plan of the figure 1 of the device according to another mode of operation; The figure 3 [Fig. 3 ] illustrates, in schematic profile view, another part of the heating, ventilation and / or air conditioning system; The figure 4 [Fig. 4 ] illustrates a perspective view of another part of the heating, ventilation and / or air conditioning system; The figure 1Figure 2 illustrates a heating, ventilation and / or air conditioning device according to the invention, comprising a housing 4 in which are housed means for thermally treating the airflow intended to be distributed in the passenger compartment. The housing 4 comprises a first flow duct 4a for a first airflow Fa, and a second flow duct 4b for a second airflow Fb.

[0025] According to the invention, the housing 4 includes a separating partition 5 arranged within the housing 4 so as to separate the first flow conduit 4a from the second flow conduit 4b.

[0026] The heat treatment means include a first heat exchanger 6, for example a radiator, intended to heat a portion of the airflow circulating in the heating, ventilation and / or air conditioning unit 2. The first heat exchanger 6 is arranged in the first flow duct 4a and in the second flow duct 4b, said heat exchanger 6 being common to both flow ducts 4 and 4b.

[0027] The heat treatment means may further include a second heat exchanger 8, corresponding to an electric heater intended to heat the airflow more rapidly, particularly when starting the vehicle. The second heat exchanger 8 is arranged downstream of the airflow from the first heat exchanger 6. The second heat exchanger is arranged within the second flow duct 4b.

[0028] The heat treatment means also include a third heat exchanger 10, for example an evaporator, arranged upstream of the first heat exchanger 6 with respect to the direction of airflow. The third heat exchanger 10 is intended to cool and dehumidify the entire airflow circulating in the heating device. The third heat exchanger 10 is arranged in the first flow duct 4a and in the second flow duct 4b, said heat exchanger 10 being common to both flow ducts 4 and 4b.

[0029] The airflow is introduced into the housing 4 through an inlet (not shown) and then directed to an outlet, after being thermally treated by the heat exchangers 6, 8, 10 via a blower (not shown).

[0030] The outlet system includes several ducts distributing airflow to nozzles opening in different areas of the passenger compartment. Specifically, the outlet system includes a first outlet duct 12 directing airflow to the footwell nozzle to warm the feet of the front and possibly rear passengers. The outlet system also includes a second outlet duct 14 conveying airflow to the defrost nozzle for demisting the windshield. The outlet system includes a third outlet duct 16 directing airflow to the side / center ventilation nozzles for cooling / warming the front passengers. The outlet system may also include a fourth outlet duct 18 to direct airflow to the rear of the vehicle for cooling / warming the rear passengers. Each outlet duct includes an access opening that can be at least partially closed by a shutter.

[0031] According to the invention, the device comprises a first flap 20 arranged downstream of the second heat exchanger 8 and abutting in an extreme position against the partition wall 5 or against the second heat exchanger 8. As illustrated in the [ Fig.1 The first flap 20 is of the butterfly type, meaning it has a pivot point located at the center of a door or a pivot point located between two doors. The first flap 20 is positioned at the first outlet duct 12. In other words, the first flap 20 is arranged so that it can at least partially block the inlet of the first outlet duct 12. As illustrated in the figure 1The first flap 20 is of the butterfly type with a rotation axis 20c arranged between two gates 20a, 20b, which are shown here inscribed in two separate planes. Of course, the two gates can also be inscribed in the same plane. The first gate 20a is capable of closing or opening access to the first outlet duct 12. The second gate 20b guides the airflow exiting the first or second heat exchanger 6, 8.

[0032] The first flap 20 pivots between two extreme positions, a first extreme position where the first flap 20, and more precisely the second door 20b, comes to rest against the partition 5 and / or the second heat exchanger 8 and a second extreme position where the first flap 20, and more precisely the second door 20b, comes to rest against a wall of the casing 4. Obviously, the first flap 20 is able to adopt any intermediate position between these two extreme positions.

[0033] In the first extreme position as illustrated in figure 2 , the first flap 20, and in particular the second door 20b comes against the partition 5 while the first door 20a comes against a wall of the casing 4, in particular a wall of the first outlet duct 12 so that the air flow that can circulate within the first outlet duct 12 is maximized.

[0034] In the second extreme position illustrated in figure 3 , the first flap 20, and in particular the second door 20b comes against a wall of the housing 4 and while the first door 20a completely closes the first outlet duct 12 so that no airflow can circulate within the first outlet duct 12.

[0035] According to the invention, the heating, ventilation and / or air conditioning device further comprises an airflow guide wall 22 arranged in the first airflow duct 4a and arranged downstream, with respect to the airflow, of the first heat exchanger 6. The airflow guide wall 22 directs the first airflow Fa towards the first flap 20.

[0036] Thus, according to the invention, the first hot air flow Fa, having passed through the first heat exchanger 6, is directed towards the first flap 20 and therefore towards the first outlet duct 12 towards the foot area in the passenger compartment.

[0037] Because of this orientation, the majority of the flow from the first heated Fa air stream is directed towards the 12-foot outlet duct.

[0038] However, according to the invention, the majority but not all of the flow of the first heated airflow Fa is directed towards the outlet duct 12 feet. Indeed, there is always a portion of the first airflow Fa that can flow towards the second and / or third outlet duct 14,16.

[0039] To this end, the housing 4 includes a space 24, or gap, between the airflow guide wall 22 and the first flap 20, such that the first flap 20 is not able to abut against the airflow guide wall 22. In other words, according to the invention, the first flap 20 is configured so that it cannot bear against the airflow guide wall 22.

[0040] As seen previously, the first part 20 pivots into an intermediate position I as illustrated in figure 1located between the two extreme positions. The airflow guide wall 22 extends substantially in a direction P, and the first flap, and in particular the second door 20b, extends substantially in a direction V. As illustrated in figure 1 , the directions P and V are substantially aligned in this intermediate position. In other words, the second door 20b is in line with the airflow guide wall 22, while maintaining a space 24 between the two elements.

[0041] In said intermediate position, the space 24 between the end of the airflow guide wall 22 and the end of the first flap 20 and in particular the end of the second door 20b is between 5 and 25 mm, preferably between 10 and 15 mm.

[0042] Thus, through this gap 24, it is guaranteed that part of the first airflow Fa having passed through the first heat exchanger 6 can always be conveyed towards the second and / or third outlet duct 14,16.

[0043] The first flow duct 4a of the first airflow Fa and the second flow duct 4b of the second airflow Fb each include a bypass path 26,28 of the first heat exchanger 6, the bypass paths 26,28 being arranged on either side of the first heat exchanger 6.

[0044] A second butterfly-type flap 30 is arranged within the first flow duct 4a of the first airflow Fa and a third sliding-door-type flap 32 is arranged within the second flow duct 4b of the second airflow Fb, said flaps being arranged between the first 6 and third 10 heat exchanger so as to direct each respective airflow Fa,Fb through the corresponding bypass path 26,28 and / or through the first heat exchanger 6.

[0045] In other words, the second butterfly-type flap 30 pivots between two extreme positions and can adopt any intermediate position, a first extreme position where the second flap 30 completely closes the passage of the airflow Fa to access the first heat exchanger 6, and a second extreme position where the second flap 30 opens the passage of the airflow Fa to the maximum to access the first heat exchanger 6. The first flow duct 4a of the first airflow Fa further includes another flap, therefore a fourth flap 34 also of butterfly type arranged within the bypass path 26 of the corresponding first heat exchanger 6.The fourth flap 34 pivots between two extreme positions and can adopt any intermediate position, a first extreme position where the fourth flap 34 completely closes the bypass path 26 of the first heat exchanger 6 and a second extreme position where the fourth flap 34 at least opposes the flow of the first airflow Fa within the bypass path 26.

[0046] The third sliding door type flap 32 slides between two extreme positions and can adopt any intermediate position, a first extreme position where the third flap 32 completely blocks the passage of the airflow Fa to access the first heat exchanger 6 and a second extreme position where the third flap 32 completely blocks the corresponding bypass path 28.

[0047] Obviously, the invention is not limited to the type of shutter for the first, second, third or fourth shutter 20, 30, 32, 34. Each shutter can correspond to a butterfly, drum, flag shutter (axis of rotation arranged at one end of a door).

[0048] As explained previously, each outlet duct 12,14,16,18 includes an associated shutter that allows each airflow Fa,Fb to flow or not within the outlet duct.

[0049] The first flap 20 is associated with the first outlet duct 12. A fifth flap 36, here of the flag type, is associated with the second outlet duct 14, directing air towards the defrosting nozzle near the vehicle's windshield. The fifth flap 36 is capable of completely blocking the second outlet duct 14. A sixth flap 38, here of the drum type, is associated with the third outlet duct 16, directing air towards the central / side ventilation nozzle. The sixth flap 38 is designed so that it is not capable of completely blocking the third outlet duct 16. In fact, the sixth flap 38 has notches (not shown) on its lateral sides to ensure an air leak of approximately 10% of the maximum flow rate, even when the sixth flap 38 is in its fully closed position, blocking the third outlet duct 16.In addition, a seventh flap 40, here of the butterfly type, associated with the fourth outlet duct 18, directs air towards the passenger ventilation nozzle at the rear of the vehicle. The seventh flap 40 is capable of completely closing the fourth outlet duct 18.

[0050] The structure of the sixth flap 38 ensures that an airflow can always be directed towards the vehicle's side windows, allowing them to be defrosted or demisted. This is particularly advantageous in defrost mode (see

[0062] ), where the sixth ventilation flap 38 is in its fully closed position, but the vehicle's windows can still be defrosted or demisted.

[0051] The first, fifth, sixth and seventh panels are called distribution panels and the second, third and fourth panels are called mixing panels.

[0052] Device 2 according to the invention may include a flap synchronization mechanism where the seventh flap 40 can be linked in rotation with the sixth flap 38 for example by means of a connecting rod.

[0053] Such an arrangement of the heating, ventilation, and / or air conditioning system 2 according to the invention allows for the use of several operating modes as described below. Only the distribution flaps will be described, as the mixing flaps depend on the temperature settings indicated by the front and / or rear passengers.

[0054] Feet Mode: In feet mode, as illustrated in figure 2, the first flap is in the open position of the first outlet duct 12, in other words, the first flap 20 is against the separation wall 5 and / or against the second heat exchanger 8. The fifth flap 36 is in the partially closed position (closed to 80%), the sixth flap 38 is in the closed position of the third outlet duct 16, with air leaks representing up to 10% of the maximum flow rate and the seventh flap is in the fully closed position of the fourth outlet duct 18.

[0055] Bi-level mode: In this mode, the first flap 20 is in intermediate position I where the second door 20b is in line with the guide wall 22 of the first heated airflow Fa, as illustrated in figure 1. The fifth flap 36 is in the position of closing the second outlet conduit 14 and the sixth 38 and seventh 40 flaps are in the intermediate opening position, that is to say between the closing position and the opening position of each corresponding outlet conduit 16,18, although the sixth flap 38 may be in the fully open position.

[0056] Foot / degi mode: in this mode, the first 20 and fifth 36 flaps are in intermediate position and the sixth 38 and seventh 40 flaps are in the position of closing each corresponding outlet duct 16,18, with air leaks for the sixth flap 38.

[0057] Ventilation Mode: the sixth (38) and seventh (40) flaps are in the open position for each corresponding outlet duct (16, 18), and the first (20) and fifth (36) flaps are in the closed position for each corresponding outlet duct (12, 14).

[0058] Defrost mode: Only the fifth flap 36 is in the open position of the outlet duct 14, the other distribution flaps are in the closed position of each corresponding duct.

[0059] The following table summarizes the different modes. For each mode: feet, defrost, etc. There are two lines. The first line corresponds to the degree of opening (percentage) of the indicated damper, with 100 representing the maximum opening, in other words, the extreme position where the damper least obstructs the airflow, and 0 representing the degree of closure of the corresponding duct. The damper values ​​are listed on the left, and the damper values ​​are indicated according to their degree of opening and the flow rate passing through them. The second line corresponds to the airflow rate within the corresponding air duct (percentage of the total airflow rate). Fashion Opening of the first part (20) Opening of the fifth part (36) Opening of the sixth / seventh section (38,40) Airflow in first outlet duct (12) (%) Airflow in second outlet duct (14) (%) Airflow in third and / or fourth outlet duct (16,18) (%) Feet 100 15 / 20 0 70 / 60 20 10 / 20 Bi-Level ~50 0 -100 60 0 40 Feet / Defrost -100 -100 0 45 / 40 45 / 40 10 / 20 Ventilation 0 0 100 0 0 100 Defrosting 0 100 0 0 90 / 80 10 / 20

[0060] Thus, according to the invention, it is possible to have several modes of operation and to have more hot air directed towards the feet.

[0061] There figure 3illustrates the air inlet housing the device includes an air inlet housing and a blower (or motor-fan unit (MFU) or blower), namely with a single turbine, in other words a bladed wheel, 54 capable of being driven in rotation around an axis A. The device 2 includes a tubular element 56 capable of delimiting a first air circulation channel 58 allowing the flow of a first air stream intended to pass through a first axial part of the turbine 54b and a second air circulation channel 60 allowing the flow of a second air stream intended to pass through a second axial part of the turbine 54a. The tubular element 56 is mounted at the location of a first end of said turbine 54 and delimits an internal space, or volume, forming at least a part of the first air circulation channel 58, the second air circulation channel 60 extending outside the tubular element 56.The device 2 further includes an air inlet housing covering the first end of the turbine 54 and the tubular element 56. The air inlet housing includes guiding means suitable for directing a first airflow into the first air circulation channel 58, and for directing a second airflow into the second air circulation channel 60. The axial parts of the turbine 54a, 54b can, for example, be made with reference to the vertical axis of the vehicle, when the device is installed in the vehicle.

[0062] For this purpose, the air inlet housing may, for example, include a first and second air inlet vents, one for recirculated air and one for fresh air, and three drum flaps with coaxial axes of rotation. The central drum flap is arranged to allow airflow between the air inlets and the first air circulation channel 58. The two lateral drums are arranged to allow airflow between the air inlets and the second air circulation channel 60. The air inlet housing 14 may also include an air filter for the first and second airflows to pass through.

[0063] The turbine 54 is arranged in a volute 62 whose outlet includes the two flow ducts 4a,4b separated by the separation wall 13 corresponding to a part of the separation partition 5. In other words, the first air circulation channel 58 directs the airflow towards a first axial part of the turbine 54b and thus opens into the second flow duct 4b, while the second air circulation channel 60 directs the airflow towards the second axial part 54a of the turbine 54 and thus opens into the first flow duct 4a.

[0064] The air blower, i.e., the impeller(s) 54, is contained within a spiral-shaped portion of the housing, commonly referred to as the volute 62. The airflow drawn in by the impeller(s) 54 is directed towards the walls of the volute 62, thus following the circular path defined by these walls. The volute 62 then has a volute outlet in the form of a straight duct, so that the airflow exiting the volute 62 follows this same direction.

[0065] The portion of the housing 4 positioned between the outlet of the volute 62 and the distribution is commonly called the divergent section. The divergent section corresponds to a channel through which the airflow exiting the volute 62 is routed to the third heat exchanger 10, in this case the evaporator 10.

[0066] Device 2 includes a partition 5 separating, or delimiting, the two flow ducts 4a, 4b from each other. This partition may be a single piece extending within the heating, ventilation, and / or air conditioning device 2 with openings to allow the introduction of the various heat exchangers 6, 8, 10, or the partition may be in several parts, or modules. There may be a first part 13 extending between the blower and the evaporator 10, a second part 5 extending between the third 10 and the first 6 heat exchanger, and a third extending above the second heat exchanger 8.

[0067] The partition 5 according to the invention is not limited to a particular shape. The partition corresponds to an element that allows the two flow conduits 4a, 4b to be separated or delimited. As illustrated in Figures 1 And 3The first part corresponds to a flat wall. The second part corresponds to a block, that is to say, a set of walls defining a non-planar or irregular shape, with abutment elements against which the second mixing flap 30 can rest, or between housings to at least partially accommodate the third mixing flap 32. The third part corresponds to an Omega-shaped wall with a housing to accommodate the second heat exchanger 8 and a buttress element against which the first flap 20, and in particular the second door 20b, rests.

[0068] Device 2 may include an air inlet housing 19 as illustrated in figure 4. Here the air inlet housing 19 has at least two separate air inlets 15, 17 extending over a width (d2) of the air inlet housing, and air guide members 77, 78, 79 configured to direct at least one airflow intended to be admitted into the air inlet housing 19.

[0069] The air guide elements comprise at least three coaxial flaps 77, 78, 79, including a central flap 77 and two lateral flaps 78, 79 arranged on either side of the central flap 77. Said coaxial flaps 77, 78, 79 are arranged between said two separate air inlet openings 15, 17 of the air inlet housing 19, in a movable manner around a single pivot axis 80. The central flap 77 extends over a portion of said width of the air inlet housing 19 greater than or equal to the portion of the width where the two lateral flaps 78, 79 extend.

[0070] The said coaxial flaps 77,78,79 are of the drum type and are each arranged movable between a first extreme position, in which said flap 77,78,79 closes a first air inlet 15, and a second extreme position, in which said flap 77,78,79 closes the second air inlet 17.

[0071] In demisting mode, the central flap 77 must be in the first extreme position of closing the second air inlet 17. The side flaps 78,79 must be in the second extreme position of closing the first air inlet 15.

[0072] In this way, the fresh air flow FE can flow within the blower through the first air inlet 15 to be guided towards the inside of the tubular element 56 and arrive at the level of the first axial part of the turbine 54b and thus open into the second flow duct 4b, and the recirculating air flow FR can also flow into the blower through the lateral flaps 78,79 which guide the recirculating air flow FR towards the outside of the tubular element 56 to arrive at the level of the second axial part of the turbine 54a and thus open into the first flow duct 4a.

[0073] Furthermore, the housing 4 includes a screen element 42 arranged at one end of the fourth shutter 34. This screen element 42, commonly called a progressive nose, is complementary in shape to the stroke of the fourth shutter 34 and extends at least partially over a portion of the shutter's stroke. In other words, the housing 4 includes a screen element 42, or a mask, that follows the curvilinear path of the fourth shutter 34. Alternatively, the screen element 42 can be said to be at least partially concave, with the fourth shutter moving within the concave portion.Indeed, the fourth flap 34 corresponds to a butterfly flap pivoting around an axis of rotation arranged between two doors or in the center of a single door, so that the door or doors adopt a circular trajectory and pivot from an extreme position where they come to rest against the housing 4 to prevent the flow of air through the bypass path 26 to another extreme position where they oppose the least flow of air.

[0074] By opening, or pivoting by a few degrees, the fourth flap 34, this creates an air intake where cold air is drawn towards the distribution which does not promote a good mix with the hot air, the result is that the defrost outlet or the ventilation outlet is colder than the set temperature given by the occupants of the vehicle.

[0075] The screen element 42 therefore allows to generate a dead zone in order to better calibrate the quantity of cold air for the gradual increase in temperature.

[0076] The fourth flap 34 is of the butterfly type and the screen element 42 is arranged in the upstream part, with respect to the flow of an air stream, of the housing 4 with respect to the fourth flap 34. In other words, the screen element 42 is arranged between the fourth flap 34 and the third heat exchanger 10, with respect to the flow of an air stream.

[0077] The housing 4 includes a second screen element 45 arranged at the other end of the flap 34. In the same way, the second screen element is of complementary shape to the trajectory of the flap door, in other words at least partially concave, so as to also generate a dead zone.

[0078] As illustrated on the figure 1, the second screen element 45 is formed by a set of plain or monobloc walls which also form the guide wall 22.

[0079] The first screen element 42 extends over at least 10% of the shutter stroke, preferably between 20% and 50% of the shutter stroke. In other words, if the fourth shutter 34 pivots within an angle range between [0°, 100°], then the concave part of the screen element 42 extends at least within the angle range between ]0°, 10°], preferably between ]0°, 20°], or even up to an angle range between ]0°, 50°] and all intermediate values.

[0080] The second screen element 45 extends over at least 5% of the shutter's travel, preferably between 10% and 30% of the shutter's travel. In other words, the concave part of the second screen element 45 extends at least within the angle range between ]0°, 10°], preferably between ]0°, 10°], or even up to an angle range between ]0°, 30°] and all intermediate values.

Claims

1. Heating, ventilation, and / or air conditioning device (2) for a motor vehicle comprising a housing (4), said housing (4) comprising: - a first flow duct (4a) for a first air flow (Fa); - a second flow duct (4b) for a second air flow (Fb); - a partition (5, 13) arranged within the housing (4) so as to separate the first flow duct (4a) from the second flow duct (4b); - a first heat exchanger (6) arranged in the first flow duct (4a) and in the second flow duct (4b), said heat exchanger (6) being common to both flow ducts (4a, 4b); - a second heat exchanger (8) arranged downstream, with respect to the flow of air, of the first heat exchanger (6) and arranged within the second flow duct (4b); - a first flap (20) arranged downstream of the second heat exchanger (8); the first flap (20) being pivotable between two extreme positions, a first extreme position where the flap abuts against the partition (5) and / or the second heat exchanger (8) and a second extreme position where said flap abuts against a wall of the housing (4), and in that the housing (4) comprises an air flow guide wall (22) arranged within the first flow duct (4a) downstream of the first heat exchanger (6) and directing the first air flow (Fa) towards the first flap (20); characterized in that the housing (4) comprises a space (24) between the air flow guide wall (22) and the first flap (20) such that the first flap (20) is not able to abut against the air flow guide wall (22), in which the first flap (20) pivots to an intermediate position (I) located between the two extreme positions, with the airflow guide wall (22) extending in a direction (P) and the first flap (20) comprising a door (20b) extending in a direction (V); in said intermediate position (I), said door (20b) being in line with the airflow guide wall (22).

2. Device (2) according to claim 1, wherein the device (2) comprises a third heat exchanger (10) arranged upstream of the first heat exchanger (6) with respect to the flow of an air flow, the third heat exchanger (10) being arranged in the first flow duct (4a) and in the second flow duct (4b), said heat exchanger (10) being common to both flow ducts (4a, 4b)3. Device (2) according to one of the preceding claims, wherein in said intermediate position (I) the space (24) between the end of the guide wall (22) of an air flow and the end of the first flap (20) is between 5 and 25 mm, preferably between 10 and 15 mm.

4. Device (2) according to one of the preceding claims, wherein the first flap (20) is capable of closing an inlet of an outlet duct (12) when said flap is positioned in the second extreme position.

5. Device (2) according to one of the preceding claims, wherein the first air flow duct (4a) and the second air flow duct (4b) each comprise a bypass path (26, 28) around the first heat exchanger (6), the bypass paths (26, 28) being arranged on either side of the first heat exchanger (6).

6. Device (2) according to claim 5, wherein a second flap (30) is arranged within the first air flow duct (4a) and a third flap (32) is arranged within the second air flow duct (4b), said flaps being arranged between the first (6) and third (10) heat exchangers so as to direct each respective air flow (Fa, Fb) through the corresponding bypass path (26, 28) and / or through the first heat exchanger (6).

7. Device (2) according to claim 6, in which the first air flow duct (4a) further comprises a fourth flap (34) arranged within the corresponding bypass path (26).

8. Motor vehicle characterized in that it comprises a heating, ventilation, and / or air conditioning device (2) according to claim 4, in which said outlet duct (12) corresponds to the foot outlet and is configured to supply air to the foot area of the passenger compartment.