FR3102235A1 - AIR DRYING DEVICE OF A MOTOR VEHICLE INTERIOR - Google Patents

Abstract

Device for drying the air of a motor vehicle cabin: Device for drying the air (2) of a motor vehicle cabin, comprising two air circulation ducts (4, 6) distinct and independent one on the other, each duct comprising a blower (14, 15) configured to force the air to circulate in the duct which is specific to it, and also comprising adsorbent material (8) arranged across the two ducts (4, 6), characterized in that the absorbent material (8) is arranged on at least two independent supports (20), each support being movable between a first position (P1) in which it extends across a first of the two air circulation ducts and a second position (P2) in which it extends across the second of the two air circulation ducts. Figure for the abstract: figure 3

Description

AIR DRYER DEVICE OF A MOTOR VEHICLE CABIN

The subject of the present invention is an air drying device for the passenger compartment of a motor vehicle, and more particularly an air drying device comprising a regenerable adsorbent material.

The invention is in particular dedicated to electric vehicles with the aim of saving consumption but also finds an advantageous application in the start-up phases of thermal vehicles, and more generally to any type of vehicle with the aim of reducing the risks of fogging of the windows.

Motor vehicles conventionally comprise a heating, ventilation and air conditioning installation, known by the English acronym HVAC for "Heating, Ventilating, Air Conditioning", which allows, via a box through which air passes and housing heat exchangers heaters and distribution flaps in particular, to provide the passenger compartment with air at a flow rate and temperature desired by the occupants of the vehicle. It is known to carry out a recycling of the air of the passenger compartment to supply the box of this HVAC installation and thus improve the energy efficiency and reduce the electrical consumption of the installation. For example, the potential gain in air conditioning mode is between 20% and 60% of air conditioning consumption, which in particular makes it possible to increase the range of an electric vehicle or an electrified vehicle in electric mode.

A disadvantage of such air recycling appears more particularly in heating mode. The air recovered in the passenger compartment, due to the presence of the occupants of the vehicle, is more laden with humidity than the fresh air that may come from outside the vehicle. This potential humidity can generate, in particular in heating mode during the recirculation of air in the passenger compartment, condensation and misting on the glass surfaces.

It is therefore advantageous to provide an operation for drying the air of a motor vehicle interior, in order to reduce the mass of water in the air, when air recirculation is controlled automatically, or manually by the occupants of the vehicle. . It is known to use the evaporator present in the HVAC installation, to cool the air intended for the passenger compartment while drying it, but the use of the evaporator for this purpose generates a surplus of energy consumption.

It is now known to carry out this drying operation by using an adsorbent material such as, for example, a zeolite, a silica gel, a material from the family of MOFs (“Metal Organic Framework”) or other materials. This material is capable of adsorbing some of the water molecules contained in the air. The adsorption reaction is exothermic, ie it produces heat which is partly transmitted to the air passing through the material. In this way, the adsorbent material placed in the recirculation duct of the HVAC installation box allows the air to be recycled in the passenger compartment to be dried.

When the material is saturated, after various successive air recirculation loops, it no longer has the capacity to retain water. It should then be regenerated, it being understood that the material can also be regenerated before being saturated.

Regeneration is carried out by heating the material or the air passing through the material in order to evaporate the water. The air which passes through the material to regenerate it, or to desorb it, is then heated and humidified and is, in the context of integration in a motor vehicle, preferably returned to the outside.

During air drying, this system does not consume energy. It has the particularity of releasing heat during the adsorption phase and requiring heat during the regeneration phase. Such passive drying by adsorption is however not commonly used in the automobile because the regeneration of the adsorbent material is restrictive.

Patent document EP3385101 describes a device for drying air by adsorption in which the adsorbent material can be regenerated when the vehicle is stationary. The regeneration phase is preferably carried out during a parking period of the vehicle and in particular when it is connected to an electrical terminal in order to benefit from the available electrical energy. Vehicles that can be connected to the fixed electrical network, such as electric vehicles, hybrid vehicles, or connectable thermal vehicles, are particularly suitable. When the vehicle is required to transport many people, or to operate for an extended period of time, the dimensioning of an air drying device by adsorption poses problems of integration into the vehicle. This is a problem that can be encountered on autonomous shuttles, for example. It is then necessary to reduce the drying device and to size it accordingly to the space allocated in the vehicle, which poses problems of vehicle autonomy.

Solutions are put in place to solve this problem of autonomy. The air drying device can thus only be used when a risk of fogging is detected, that is to say when sensors detect that conditions are approaching which favor the appearance of fogging on the windows. . This makes it possible to adjust the air flow passing through the adsorption drying device in order to preserve its autonomy according to the need and to meet the need for reducing the humidity of the air which can be to prevent the appearance of condensation on the windows.

It is also known to regenerate the adsorbent material while the vehicle is moving. Regeneration is implemented when dryer performance decreases to a low level that warrants regeneration.

The document US5697223 discloses an air dryer arranged at a distance from the housing of the HVAC installation and consisting of a duct in which adsorbent material and a heating element are arranged in series. The heating element is electrically powered when a regeneration phase is required, and it is passive when an adsorption phase is in progress. It is understood that such an arrangement involves operation in which the material is either in the adsorption phase or in the regeneration phase, and therefore does not allow continuous operation in adsorption.

Document US5509275 discloses a dryer integrated into the housing of the HVAC installation capable of operating continuously, with the adsorbent material arranged on a desiccant wheel, a first part of which is traversed by moist air to be dried and a second part of which is simultaneously traversed by hot air to regenerate the adsorbent material present in said second part. The presence of a desiccant wheel and means for driving this wheel in rotation inside a housing of the HVAC installation generates a bulk which does not facilitate the implementation of such a solution on vehicles. serial.

In this context, the invention aims to propose a device forming an alternative to air drying devices known for their application in motor vehicles, this device having to be suitable for use in particular when the vehicle equipped with this device operates in a mode air recirculation, and to allow easy integration into the vehicle.

For this, the invention proposes a device for drying air in the passenger compartment of a motor vehicle, comprising two separate and independent air circulation ducts, each duct comprising a blower configured to force the air circulating in the duct which is specific to it, and further comprising adsorbent material arranged across the two ducts.

The invention is characterized in that the absorbent material is arranged on at least two independent supports, each support being movable between a first position in which it extends across a first of the two air circulation ducts and a second position in which it extends across the second of the two air circulation ducts.

In other words, the invention proposes a demisting system with air drying by adsorption by means of an adsorbent material of the zeolite, silica gel, or MOF type which makes it possible to operate continuously during the whole vehicle driving.

A drying device according to the invention has the advantage of allowing continuous dehumidification, with regeneration on demand of part of the adsorbent material. Advantageously, according to the invention, the distribution of the adsorbent material on independent supports each able to move from one pipe to another makes it possible to vary the quantity of adsorbent material in adsorption mode and the quantity in regeneration mode. It is thus possible to adapt the regeneration period of the material according to the driving conditions and to optimize the autonomy of the drying device before the adsorbent material is saturated. This avoids the need for sensors that define a humidity level in the passenger compartment to activate drying on demand and adjust the need for use of the adsorbent material, or else having to oversize the quantity of adsorbent material so that it is effective for long periods of vehicle travel.

According to one characteristic of the invention, the ducts each comprise an exchange zone in which the said supports are arranged, the ducts being configured so that the said exchange zones are arranged close to each other and that a passage is provided between the exchange zones to allow the translation of the supports from one exchange zone to another.

By proximity, we understand that the exchange zones are in contact with each other, with a common wall if necessary which participates in delimiting the two independent air circulation ducts and in which the passage is provided. In all cases, that is to say whether there is a common wall or not, the passage provided between the exchange zones is sealed in that the air circulating in one or other of the conduits do not leak through this passage.

According to a characteristic of the invention, each support is movable in translation from the first position to the second position. Advantageously, the configurations in which the supports are moved in rotation are thus avoided, which are more particularly suited to devices in which the same air duct is able to generate an adsorption function and a regeneration function. Such a drying device can thus fit into a reduced footprint since any rotational movement of a desiccant wheel or flaps directing the air brought to cross the adsorbent material in one direction or the other is avoided.

More particularly, provision is made for each support to be movable in translation between two extreme stop positions, said support being able to stop in one or the other of these extreme stop positions. The operation can be described as binary in that each adsorbent material support is capable of taking only two working positions, namely either a first position entirely in a first duct, or a second position entirely in a second duct. The plurality of supports makes it possible to play on the number of supports present in a first conduit and present in a second conduit, and thus to adapt the rate of adsorption and regeneration, with a simple binary control to implement.

According to one characteristic of the invention, each support is movable in translation in a direction perpendicular to the main direction of elongation of the air ducts in their exchange zone. By main direction of elongation, it is appropriate to refer to a direction of circulation of the air brought to cross the duct, that is to say a direction parallel to a median axis of the corresponding duct in the exchange zone .

According to one characteristic of the invention, the device comprises a control unit configured to determine a humidity level of the adsorbent material placed on at least one mobile support, and to define a movement control instruction for at least one mobile support Consequently.

The adsorbent material can be placed on an even number of mobile supports and the movement control instruction as mentioned above is generated to distribute the mobile supports evenly in each of the ducts. In this way, each time, a constant quantity of adsorbent material is in adsorption mode and in regeneration mode.

According to one characteristic of the invention, the device comprises a heating member in one of the two air circulation ducts. The heating element is arranged upstream of the exchange zone with respect to the direction of circulation of the air brought to cross the corresponding duct, or in other words, between the exchange zone and the blower. In this way, the air blown by the blower and which goes towards the exchange zone first passes through the heating element, so as to improve the regeneration of the adsorbent material.

The heating member can take different forms, including that of a radiator through which a heat transfer fluid passes and configured to revalorize the thermal losses of electronic components, of a battery or of an internal combustion engine, or else that of a an electric radiator, for example with PTC effect, it being understood that these examples are not limiting of the invention. The heating element operates here continuously, since air systematically passes through the so-called regeneration duct.

According to one characteristic of the invention, the device comprises at least one humidity sensor or one pressure sensor in one of the two air circulation ducts. The sensor or sensors is connected to the control unit associated with the device, so as to allow the control of the movement of the adsorbent material supports according to data relating to humidity or pressure, that is to say as a function of information relating to the adsorption capacity of the adsorbent material present in the duct operating as an adsorption duct, and/or as a function of information relating to the state of regeneration of the adsorbent material present in the duct functioning as a regeneration conduit.

It is possible to have two humidity sensors, or two pressure sensors, in the same circulation duct, on either side of the exchange zone. It is understood that when a single sensor is present in the pipe, the value measured and sent to the control unit is compared with a table of values and with one or more threshold values, in order to determine whether an appropriate regeneration state is reached or if adsorption properties have become insufficient. When two sensors on either side of the exchange zone measure the same state of the air circulating in the duct, the two measured values are compared with each other and the state is thus assessed. of the adsorbent material and its ability to continue to adsorb moisture from passing air.

According to one characteristic of the invention, the device comprises means for actuating the mobile supports, said actuating means being in communication with the control unit.

By way of non-limiting example, the actuating means may consist of an endless screw driven in rotation by an actuator, and of a rack secured to each support, capable of cooperating with the endless screw.

The device further comprises means for guiding the support in translation in the duct, with rails for example.

According to one characteristic of the invention, each support comprises an air filter placed in parallel with the adsorbent material. Alternatively, an air filter can be placed in one of the ducts upstream and/or downstream of the exchange zone.

According to one characteristic of the invention, the air drying device consists of a separate module from a casing of a heating, ventilation and air conditioning installation of a motor vehicle.

Advantageously, such a configuration makes it possible to obtain a reduced dimensioning of the housing of the heating, ventilation and air conditioning installation, whereas the space available in the vehicle around this housing is minimal. Having a separate module, with its own air inlet and outlet ducts, allows the air dryer to be located in areas of the vehicle where space is less.

Furthermore, the fact of having an independent module facilitates accessibility to the adsorbent material supports, in particular for their replacement once their lifespan has been reached, as well as to the drive means of these supports, to facilitate possible maintenance operations.

Of course, the different characteristics, variants and embodiments mentioned above can be associated with each other in various combinations, insofar as they are not incompatible or exclusive of each other.

The invention also relates to a thermal management system for the passenger compartment of a motor vehicle, comprising a casing of a heating, ventilation and air conditioning installation in which a plurality of pipes, distribution flaps and heat exchangers are arranged is configured to allow air to be supplied to the passenger compartment at a given temperature and at a given flow rate, said system further comprising a device for drying the air in the passenger compartment according to one of the preceding and independent claims said housing and these pipes.

The invention also aims to protect a method for controlling dehumidification of a passenger compartment implementing a drying device as described above, during which the position of at least one support of adsorbent material is modified during rolling of the vehicle.

The modification of the position of at least one support of adsorbent material can be a function of a state of pressure or humidity measured in at least one of the air circulation ducts.

The invention also relates to a motor vehicle comprising an air drying device as previously described. It should be noted that the invention applies in the automotive sector in the broad sense, that is to say including utility vehicles or passenger transport vehicles such as buses, minibuses and shuttles.

The invention is mainly dedicated to electric vehicles with the aim of saving consumption but also finds an advantageous application in the start-up phases of thermal vehicles, and more generally to any type of vehicle with the aim of reducing the risks of fogging.

The invention will be better understood on reading the following description and on examining the accompanying figures. These figures are given for illustrative purposes only, being in no way limiting of the invention:

is a schematic illustration of a vehicle equipped on the one hand with a casing of a heating, ventilation and air conditioning installation, and on the other hand with an air drying device according to the invention, autonomous and independent of this installation;

is a schematic illustration of an air drying device according to the invention, making visible in particular two ducts equipped respectively with an exchange zone and a blower;

is a schematic illustration of the air drying device of FIG. 2, in which the walls delimiting each duct have been removed to make the exchange zone visible;

is a schematic illustration of the air dryer device of Figure 2, in which a wall delimiting the exchange zone in each duct has been removed to make visible supports of adsorbent material sliding from one duct to another, in accordance to the invention;

is a schematic illustration of the exchange zones of the air drying device, with the material supports in a first operating position;

is a schematic illustration similar to that of Figure 5, with the material supports in a second operating position;

is a schematic illustration of an alternative embodiment of the drying device according to the invention, with the material supports arranged in an operating position similar to that of FIG. 6;

is a schematic illustration of the alternative embodiment of FIG. 7, with the material supports arranged in another operating position;

is a front view of an air dryer device according to a particular embodiment of the invention;

is a sectional view of the air dryer device of figure 8, more particularly centered on the exchange zone of a regeneration circuit, to make visible the integration of the adsorbent material supports in this exchange zone ;

is a sectional view of the air dryer device of FIG. 8, more particularly centered on the exchange zone of an adsorption circuit, to make visible the integration of the adsorbent material supports in this zone of exchange ;

is a cross-sectional view of a detail of the air drying device of FIG. 8, making more particularly visible the means for driving the supports of adsorbent material in the exchange zones;

is a flowchart illustrating a method of drying cabin air forming one aspect of the invention.

In the following description, identical, similar or analogous elements retain the same reference from one figure to another.

As a reminder, the invention proposes a device for drying air in the passenger compartment of a motor vehicle, comprising an adsorbent material placed on a plurality of supports independent of each other and able to move so as to be across either a air circulation duct called adsorption duct or a separate duct called regeneration duct.

An air drying device 2 according to the invention is suitable for equipping a motor vehicle as illustrated in FIG. 1. The vehicle V comprises in particular an HVAC installation box 1, that is to say an installation heating, ventilation and air conditioning.

The air drying device 2 is illustrated here as being arranged in the base, under the passenger compartment, of the vehicle. It will be understood that the position of the air drying device is not limiting of the invention.

Schematically, the drying device comprises at least a first air inlet 10 recovered in the passenger compartment and a first air outlet 12 opening into this passenger compartment, as well as a second air inlet 11 and a second air outlet. air 13, here directed towards the outside of the vehicle. The first air inlet and the first air outlet are arranged at the ends of an air circulation duct, called the adsorption duct, so as to form an air recirculation loop for the passenger compartment. The air taken from the passenger compartment is treated by the drying device to come out dry due to the phenomenon of adsorption.

It should be noted, as shown in Figure 1, that the passenger compartment air recirculation loop that helps form the drying device is separate from a recirculation loop formed by the heating system, vehicle ventilation and air conditioning. A box of such an installation is present in particular between the front compartment and the passenger compartment, and it should be noted here that the drying device according to the invention consists of a separate module from this box and can therefore be installed remotely, especially in areas, here under the floor, in which space is less of a problem than in the front compartment.

In this way, the casing of the heating, ventilation and air conditioning installation, in which a plurality of pipes, distribution flaps and heat exchangers are arranged, and the drying device, independent of said casing and of these pipes , forms a thermal management system for the passenger compartment of a motor vehicle making it possible in particular to properly manage the problems of misting of the windows during the operations of recycling the air in the passenger compartment.

The module forming an air drying device according to the invention will be described in more detail, with reference initially to Figures 2 to 8.

The air drying device 2 comprises in particular two air circulation ducts 4, 6 which are distinct and independent of each other, and configured to be each traversed in an exchange zone 5, 7 by adsorbent material. 8 visible in Figures 3 and 4 in particular.

Each duct has an air inlet end 10, 11 and an opposite air outlet end 12, 13, between which are arranged the exchange zone 5, 7 mentioned above and a blower 14, 15, the blower being arranged between the air inlet end and the exchange zone. The blower is configured in particular to force the air entering the duct via the inlet end to cross the exchange zone.

In accordance with what has been described previously, at least a first inlet end 10 and a first outlet end 12, arranged at the ends of the same duct, open into the passenger compartment to form an air recirculation loop . The corresponding duct forms an adsorption duct 4, aimed at capturing the humidity of the air passing through it in order to be able to reinject dry air into the passenger compartment. The other duct forms a regeneration duct 6 and it may be provided that the air inlet and outlet ends 11, 13 associated with this regeneration duct are directed towards the outside of the vehicle.

The regeneration duct 6 is also equipped with a heating means, here taking the form of an electric heater 16 inserted across the duct and which will be described in more detail with reference to Figure 4.

Depending on the arrangement of the device in the vehicle, and in particular depending on the size of the area in which the device is arranged, the shape and arrangement of the inlet and outlet vents arranged at the ends of each duct may vary. It is however possible to define a main direction of elongation of the air circulation ducts at the level of their exchange zone 5, 7, as being a direction parallel to the central axis X of the corresponding duct. When air is forced inside the duct, this main direction of elongation at the level of the exchange zone corresponds to the main direction of the air flow in this zone. The directions of elongation of the two ducts in their exchange zone are parallel to each other.

In the example illustrated in FIG. 2, the exchange zone 5, 7 of each conduit 4, 6 is produced by two drawers 18, 19 arranged one after the other and made integral with one of the other and integral with the walls forming a circulation conduit upstream and downstream of the exchange zone. More particularly, a first drawer 18 extends across each of the two ducts and participates in forming each of these two ducts, and a second drawer 19 extends in the same way across each of the two ducts while participating in forming each of these two conduits. Provision may in particular be made for the drawers to be fixed to each other and to the walls forming the ducts by reversible fixing means such as clamping screws or else by irreversible fixing means such as welding, provided that the connection between these various components is airtight.

As is more particularly visible in Figure 3, in which the drawers have been removed, adsorbent material 8 is able to be arranged across the two ducts at the level of the exchange zones. More particularly, adsorbent material 8 is placed on independent supports 20, here four in number, taking the form of a frame inside which is placed a portion of adsorbent material, and these independent supports are sized to be arranged across one or the other of the two ducts. Each support 20 may comprise an air filter, here not visible, which is fixed to the frame by being placed across the air flow, advantageously downstream of the adsorbent material.

Each support 20 is movable in translation between a first position P1 in which it extends across the adsorption duct 4 and a second position P2 in which it extends across the regeneration duct 6. More particularly, each support 20 is movable in translation between these two positions in a direction perpendicular to the main direction of elongation of the air ducts in their exchange zone.

Each drawer is configured to accommodate two 20 mobile supports inside the drawer. The drawer 18, 19 consists of a frame within which the supports can move in translation and whose walls make it possible to guide each of the supports 20 in its movement in translation. The drawer thus generates in a middle zone a passage 21 between the ducts, through which the supports are able to pass from one exchange zone to another. In accordance with what is visible in Figure 3, this passage is dimensioned so that it is substantially filled by the walls of the supports 20 when the latter are in the first position P1 or in the second position P2, so that a relative tightness from one duct to another is respected. A seal may be provided, arranged on the internal face of the drawer in the middle zone forming the passage, and against which the support rubs when it moves through the passage from one duct to another. However, as pulsed air is intended to be present in each duct, an adjustment of the two mobile supports to the dimensions of the section of the drawer in the middle zone may be sufficient to prevent the air circulating in a duct from passing into the other.

The air drying device also comprises drive means 22 for each of the drawers, these drive means being able to be controlled by a control unit, here not shown, independently from one drawer to the other. 'other.

The control unit comprises electronic components capable of establishing a control instruction relating to the configuration of the exchange zones. In particular, the control module is configured to determine a movement control instruction of at least one mobile support.

The drive means here comprise, for each drawer, a motorized shaft 24 which extends perpendicular to the main direction of elongation of the ducts and perpendicular to the direction of movement of the supports 20, this shaft carrying at least one toothed pinion 26, here two arranged near each end of the shaft. The supports 20 each comprise on their side two racks 28 fixed respectively on each edge of the frame extending parallel to the direction of movement of the supports. The supports are arranged in each drawer in such a way that the racks 28 mesh with the corresponding toothed pinion, the motorized shaft and its toothed pinions being arranged between the two supports.

It is understood that the rotation of the motorized shaft generates the rotation of the toothed pinions and the displacement in translation, in a first direction, of the racks fixed to the first support and, in a second opposite direction, of the racks fixed to the second support.

At least one element integral with the drawer forms a means of guiding the supports 20 in translation, making it possible to ensure contact between the racks and toothed pinions. As illustrated in Figure 4 and visible due to the shrinkage in this figure of the walls forming the air circulation ducts, this integral element of the drawer may in particular consist of a transverse edge 30 of the drawer.

Furthermore, the side walls 32 of the drawer, that is to say the walls perpendicular to the direction of translation of the supports, form stops for the movement of the supports 20. The drive means are controlled so that the supports move between two stop positions in which each support is in contact with a side wall of the corresponding drawer.

In the example illustrated, two drawers 18, 19 are arranged one after the other, but it will be understood that this arrangement is not limiting of the invention, so that other drawers could be arranged in sequence, each carrying one or more adsorbent material supports, or else so that a single drawer could be arranged to form the exchange zones.

As described previously, the regeneration duct 6 is equipped with an electric heater 16. The electric heater comprises heating elements, here elements with a Positive Temperature Coefficient, or with PTC effect, capable of generating calories following a power supply appropriate electric, and radiant elements allowing to diffuse the heat and to increase the surface of heat exchange with the air passing through the radiator.

As soon as the supports 20 and the corresponding adsorbent material are positioned in the regeneration duct 6, the electric heater 16 is powered to allow heating of the air circulating in the duct. The electric heater 16 is positioned between the exchange zone 7 of the regeneration duct and the air inlet end 11, and therefore the blower 15. Considering the direction of air circulation, the electric heater is arranged upstream of the exchange zone 7 of the regeneration conduit 6.

In the configuration illustrated in FIG. 5, and also visible in FIGS. 3 and 4, the supports are evenly distributed between the two ducts, the adsorbent material being placed on an even number of mobile supports. In this way, a constant quantity of adsorbent material is in adsorption mode and in regeneration mode. More particularly, in the configuration illustrated, a first support 20a housed in the first drawer 18 is arranged in the adsorption duct 4 and the second support 20b housed in the first drawer 18 is arranged in the regeneration duct 6. Similarly , a third support 20c housed in the second drawer 19 is arranged in the adsorption duct 4 and a fourth support 20d housed in the second drawer 19 is arranged in the regeneration duct 6.

The configuration illustrated in Figure 6 is obtained after the actuation of each of the drive means associated with the drawers. More specifically, the two motorized shafts 24 have been driven in rotation and the cooperation of these shafts with the racks 28 of the supports has generated a movement in translation of each of the supports. In the first drawer 18, the supports 20 being in opposition with respect to the associated motorized shaft 24, the rotation of the latter in a first direction R1 generates a movement in translation in a first direction T1 of the first support 20a and a simultaneous movement in translation, in a second opposite direction T2, of the second support 20b. The movement takes place in the same way in the second drawer 19, it being understood that the control unit which controls the actuation of the drive means can generate a movement control instruction for the supports of the first drawer 18 without however requesting the displacement of the supports of the second drawer 19, this instruction being able for example to be shifted in time.

The passage from the first configuration to the second configuration is decided by the control unit. The control instruction generated by the control unit can be carried out cyclically, at regular intervals while driving, or according to predefined time intervals depending on the driving conditions, for example the speed of the vehicle, or the temperature. exterior. As will be detailed below, the control instruction can advantageously be carried out according to measurements carried out inside the ducts to define whether the adsorption function is effective over time.

In each of the configurations, the adsorbent material 8 present in the regeneration duct 6 is traversed by the air previously heated by the electric heater 16, and it is regenerated in order to be able subsequently to be effective again in adsorption. As illustrated in Figures 5 and 6, adsorbent material is continuously present in the adsorption duct, to provide the air drying function continuously while the vehicle is running, and part of the material adsorbent is simultaneously being regenerated in an independent conduit.

When it is estimated by the control unit that the adsorbent material present in the adsorption duct 4 in the second configuration of FIG. 6 is no longer in a condition to effectively perform an adsorption function, an instruction to rotation of at least one motorized shaft in a second direction, opposite to the direction of rotation R1 mentioned above, will be generated, so that the corresponding supports 20 will translate to resume their position of the first configuration of Figure 5.

It should however be understood that, without departing from the context of the invention, the distribution of the supports in one or the other of the ducts may vary, in particular according to the driving conditions of the vehicle, and according to the state regeneration of the adsorbent material. This is particularly the case in a variant illustrated in Figures 7 and 8.

This variant differs from the above in that the drive means are specific to each support and no longer common to two supports housed in the same drawer. Schematically, these drive means have here been represented by a plurality of drive cables 34 respectively secured to a support 20.

The control unit can generate control instructions specific to each drive means, so that each adsorbent material carrier can be moved independently of each other. As illustrated, this makes it possible to pass from a first configuration illustrated in FIG. 7, in which the number of supports, and therefore the quantity of adsorbent material, is equivalent from one conduit to the other, to a second configuration, in which the number of supports differs from one conduit to another. Arbitrarily, a second configuration has been illustrated here in Figure 8 in which a greater quantity of adsorbent material has been placed in the adsorption duct than in the regeneration duct. In particular, situations could thus be provided where all of the adsorbent material is in the regeneration duct, in particular when it has been identified that the air present in the passenger compartment is not humid, or else situations where the all of the adsorbent material is in the adsorption duct, in particular when it has been identified by measurements internal to the adsorption and regeneration ducts that all of the adsorbent material is operating optimally.

Figures 9 to 12 illustrate a particular embodiment of the invention. A difference with what has been previously described is in particular that the direction of air circulation in the exchange zone of the adsorption duct and in the exchange zone of the regeneration duct is the same, whereas the directions of circulation were parallel but opposite in what was previously described.

Furthermore, Figure 9 makes visible the actuators 40 capable of controlling the drive means of the supports. These actuators are here fixed on a transverse wall 42, 43 of the drawers 18, 19 and they are connected to the motorized shaft 24 as can be seen in particular in FIG. 12. These actuators 40 are each connected to the control unit as previously described, this control unit being in particular configured to generate first control instructions addressed to a first of the actuators and second control instructions, similar or not to the first control instructions, to the second of the actuators.

The air drying device illustrated here comprises a plurality of sensors 44 arranged on each conduit 4.6 on either side of the exchange zone 5.7. These sensors 44 are here humidity sensors configured to determine a humidity value of the air circulating in the duct. Other types of sensors could be implemented, and for example pressure sensors.

Each sensor 44 is in communication with the control unit which deduces from the measurements taken by these sensors a state of the adsorbent material, and more particularly a level of adsorption of the material. If the measurement of the sensors 44 arranged in the adsorption duct makes it possible to define that the humidity present in the air before it passes through the exchange zone 5 of the adsorption duct is entirely or almost entirely captured by the adsorbent material present in the adsorption duct 4, the level of adsorption of the material is considered sufficient and no regeneration operation is ordered. In this way, the adsorbent material present in the adsorption duct remains in place. Conversely, if the measurement of the sensors 44 arranged in the adsorption duct makes it possible to define that the humidity present in the air before it passes through the exchange zone 5 of the adsorption duct is still present in the air after passing through this exchange zone 5, the level of adsorption of the material is deemed insufficient and a regeneration operation is ordered, by translation of the adsorbent material from the adsorption duct to the regeneration duct.

It is understood that what was previously described on the first and second configurations with reference to Figures 5 and 6 apply to the particular embodiment which has just been described. In this way, at each translation of adsorbent material in the direction of the regeneration duct so that the latter is heated and regenerated, a translation of regenerated adsorbent material is carried out in the other direction, so that adsorbent material is present. continuously in the adsorption duct.

Another difference, without this being limiting of the invention and having an impact on the mobility of the adsorbent material supports in one or the other of the independent ducts, consists here in the structure of the adsorption duct which here comprises a single air inlet and two outlet ends.

A method for controlling the dehumidification of the air present in the passenger compartment of the vehicle can thus be implemented to ensure adsorption of the humidity of the recycled air and this in a continuous manner while the vehicle is in motion.

This method implements a drying device similar to what has just been described in one or other of the embodiments, the method aiming to modify the position of at least one support of adsorbent material during the vehicle driving. This modification of the position of the adsorbent material in one or other of the independent ducts is advantageously a function of a state of pressure or humidity measured in at least one of the air circulation ducts.

More particularly, and as illustrated in FIG. 13, the method comprises a first step E1 of measuring an adsorption level of the adsorbent material present in the adsorption duct and/or in the regeneration duct. In particular, it can be decided that the operation of moving the adsorbent material is carried out when measurements in the adsorption duct show that the adsorbent material present in this adsorption duct is no longer efficient enough, i.e. say too saturated, or that the operation of moving the adsorbent material is carried out when measurements in the regeneration duct show that the adsorbent material present in this regeneration duct is again fully effective, that is to say no longer at all saturated.

The first step E1 is in particular implemented when vehicle driving information I1 is detected. The measurement of an adsorption level can in particular consist of a measurement of a humidity level of the air circulating in the adsorption duct upstream and downstream of the exchange zone, that is to say i.e. upstream and downstream of the adsorbent material. The measured V values are then sent to the control unit.

In a second calculation step E2, the control unit analyzes the measured values relating to the level of adsorption. In the example illustrated, the control unit compares the values of the humidity rate of the air before and after passing through the adsorbent material and deduces therefrom a datum relating to the adsorption capacity of the material. This data is compared to a threshold value stored in the control unit and two types of action result depending on the result of this comparison. If the data relating to the adsorption capacity is greater than the threshold value, which in other words means that the adsorbent material present in the adsorption conduit is still sufficiently effective, the position of the supports is left in the state and a new adsorption measurement step E1 is launched.

If the data relating to the adsorption capacity is lower than the threshold value, which in other words means that the adsorbent material present in the adsorption conduit is too saturated to be effective, a modification of the position of the supports is controlled, so that the adsorbent material present in the adsorption duct is moved into the regeneration duct and so that, where appropriate, the adsorbent material present in the regeneration duct is moved to take place in the regeneration duct.

In this case, a third step E3 of displacement by translation of at least part of the supports is generated. At the end of this third step, a new step E1 of adsorption measurement is launched. The method according to the invention is thus continuous as long as the vehicle is in motion.

The invention as it has just been described fulfills the objectives it has set itself well, in that it allows, during operations for recycling the air of a vehicle passenger compartment, a drying of this air to prevent the windows from misting up without penalizing the size of a heating, ventilation and air conditioning system present elsewhere in the vehicle.

Of course, the embodiments described above can be associated with each other, in various combinations, to obtain new embodiments.

Claims (15)

Air drying device (2) of a motor vehicle passenger compartment, comprising two air circulation ducts (4, 6) distinct and independent of each other, each duct comprising a blower (14, 15 ) configured to force the air in circulation in the duct which is specific to it, and also comprising adsorbent material (8) arranged across the two ducts (4, 6),
characterized in that the absorbent material (8) is arranged on at least two independent supports (20), each support being movable between a first position (P1) in which it extends across a first of the two circulation ducts of air and a second position (P2) in which it extends across the second of the two air circulation ducts. Device according to Claim 1, characterized in that the ducts (4, 6) each comprise an exchange zone (5, 7) in which the said supports (20) are arranged, the ducts being configured so that the said exchange zones are arranged close to each other, and that a passage (21) is provided between the exchange zones (5, 7) to allow the translation of the supports (20) from one exchange zone to the other. Device according to Claim 1 or 2, characterized in that each support (20) is movable in translation from the first position (P1) to the second position (P2). Device according to Claims 2 and 3, characterized in that each support (20) is movable in translation in a direction perpendicular to the main direction of elongation of the air ducts (4, 6) in their exchange zone (5 , 7). Device according to one of the preceding claims, characterized in that it comprises a control unit configured to determine data relating to the adsorption capacity of the adsorbent material (8) placed on at least one mobile support (20), and to define a movement control instruction of at least one mobile support accordingly. Device according to the preceding claim, characterized in that the adsorbent material (8) is arranged on an even number of mobile supports (20) and in that the said movement control instruction is generated to distribute the mobile supports equitably in each of the ducts (4, 6). Device according to one of the preceding claims, characterized in that it comprises a heating member (16) in one of the two air circulation ducts (4, 6). Device according to one of the preceding claims, characterized in that it comprises at least one humidity sensor (44) or one pressure sensor in one of the two air circulation ducts (4, 6). Device according to one of the preceding claims, in combination with claim 5, characterized in that it comprises means (22) for actuating the movable supports (20), the said actuating means being in communication with the unit control. Device according to one of the preceding claims, characterized in that each support (20) comprises an air filter arranged parallel to the adsorbent material (8). Device according to one of the preceding claims, characterized in that it consists of a module distinct from a casing (1) of a heating, ventilation and air conditioning installation of a motor vehicle. Thermal management system for the passenger compartment of a motor vehicle, comprising a casing (1) of a heating, ventilation and air conditioning installation in which a plurality of ducts, distribution flaps and heat exchangers are arranged is configured to allow air to be supplied to the passenger compartment at a given temperature and at a given flow rate, said system further comprising a device (2) for drying the air in the passenger compartment according to one of the preceding and independent claims said housing and these pipes. Method for controlling the dehumidification of a passenger compartment implementing a drying device (2) according to one of Claims 1 to 11, during which the position of at least one support (20) of adsorbent material (8 ) while driving the vehicle. Method according to claim 13, in which the modification of the position of at least one support (20) of adsorbent material (8) is a function of a state of pressure or humidity measured in at least one of the circulation ducts of air (4, 6). Motor vehicle comprising an air-drying device according to one of Claims 1 to 11.