The present disclosure relates to an air conditioning system for cooling a room. Preferably, this is an air conditioning system to be mounted on the roof of a vehicle (for example, a motorhome or a travel trailer).
The principle of the production of refrigeration, on which air cooling is based, by means of a cooling circuit has long been known and is described, for example, in WO 2007/042065 A1. Such air conditioning systems usually have two fans and two heat exchangers: one fan and one associated heat exchanger belong to the evaporator, in which the air of the room to be cooled is cooled by interaction with the refrigerant. Another fan and an associated heat exchanger belong to the condenser, in which thermal energy of the refrigerant is transferred to the ambient air and thus dissipated.
Air conditioning systems or air distributors for motor vehicles are taught, for example, in DE 10 2009 028 522 B4, US 2009/0239463 A1, US 4,712,611, US 4,991,646, US 3,528,607 or CN 204006805 U.
It is therefore the object of the present disclosure to propose an air conditioning system having improved characteristics compared to the prior art.
The present disclosure achieves the object by an air conditioning system for the cooling of air, including an evaporator heat exchanger, wherein the air to be cooled passes through the evaporator heat exchanger, wherein a distributor structure is arranged upstream of the evaporator heat exchanger, and wherein the distributor structure substantially uniformly distributes the air to be cooled over a side of the evaporator heat exchanger.
The evaporator heat exchanger is part of the evaporator in which the thermal energy of the air to be cooled is transferred to the coolant, so that the cooling of the air is obtained. For this purpose, the air is guided through the evaporator heat exchanger. The air conditioning system is, for example, a so-called roof-mounted air conditioning system, which means that it is mounted on the roof of a travel trailer or motorhome, for example. In order to optimize the cooling capacity, a distributor structure is provided here, which distributes the air to be cooled as uniformly as possible over one side of the evaporator heat exchanger. The air to be cooled thus flows against this side, which is also the side facing the aforementioned distributor structure. By evenly distributing the air supplied, the interaction with the coolant that flows through the evaporator heat exchanger can thus also be optimized.
One example embodiment provides that the air conditioning system includes an evaporator fan, and that the evaporator fan is arranged opposite the distributor structure relative to the evaporator heat exchanger. In this example embodiment, an evaporator fan draws the air to be cooled through the evaporator heat exchanger. As a result, the air to be cooled first flows into the space between the distributor structure and the evaporator heat exchanger, passes through the evaporator heat exchanger, and then is directed through the evaporator fan. Or in other words, the evaporator heat exchanger is located between the distributor structure and the evaporator fan.
One example embodiment includes that the distributor structure has at least one bulge that rises toward the evaporator heat exchanger. In this example embodiment, the distributor structure is defined more specifically in that it has a kind of protrusion that extends toward the evaporator heat exchanger. This bulge or dent thus also reduces the distance from the evaporator heat exchanger. The distributor structure therefore approaches the evaporator heat exchanger in the region of the bulge, thus reducing the space for the air to be cooled in front of the evaporator heat exchanger. In one example embodiment, the bulge is a kind of wave the flanks of which extend toward the sides from which the air to be cooled is brought in. In one example embodiment, the bulge is symmetrical with respect to a center. In an alternative example embodiment, the bulge is formed to be asymmetrical. In one example embodiment, the air to be cooled flows into the space in front of the evaporator heat exchanger from two sides, and the bulge is located essentially between these two inflow sides.
One example embodiment provides that the bulge is configured and arranged in relation to the evaporator heat exchanger such that in a region of a maximum extent of the bulge, a distance between the bulge and the evaporator heat exchanger is at least 50% smaller than in other regions of the bulge. The bulge reduces the distance from the evaporator heat exchanger, through which the air to be cooled is passed. In this example embodiment, the distance is reduced to more than half in the region in front of the maximum extent. The maximum extent here is the tip or, depending on the example embodiment, the center of gravity of the bulge.
One example embodiment includes that the bulge is configured and arranged in relation to the evaporator heat exchanger such that a distance between the bulge and the evaporator heat exchanger decreases along a height profile of the evaporator heat exchanger. In this example embodiment, the bulge is configured and arranged along a height profile of the evaporator heat exchanger in such a way that the space in front of the evaporator heat exchanger narrows upward. Upward is understood here to mean away from the base surface of the air conditioning system. This is the base surface which in the installed state rests, for example, on a roof of a movable vehicle. The space into which the air to be cooled flows is therefore larger in the foot area of the evaporator heat exchanger than in the head area.
One example embodiment provides that the air conditioning system includes a housing, the evaporator heat exchanger is located within the housing, and the bulge is part of the housing. In this example embodiment, the housing is formed such that it includes the distributor structure.
One example embodiment includes that a maximum extent of the bulge is arranged within a projection of an effective area of the evaporator fan. In this example embodiment, the bulge is in the form of a kind of wave or dune, with the tip or, depending on the example embodiment, the center of gravity of this wave being located in the region along the effective area of the evaporator fan. Therefore, the smallest space for the air to be cooled is in front of the evaporator heat exchanger in the direction of movement upstream of the effective area of the evaporator fan.
In a further example embodiment, the air conditioning system has a housing, wherein the evaporator heat exchanger is arranged on a bearing surface of the housing, and wherein the bearing surface includes at least two fins.
The evaporator heat exchanger is a part of the evaporator in which the thermal energy of the air to be cooled is transferred to the coolant. For this purpose, the air is passed through the evaporator heat exchanger. The evaporator heat exchanger is arranged in a housing, resting on a bearing surface. Insofar as the air conditioning system involved is a so-called roof-mounted air conditioning system, which means it is mounted on the roof of a travel trailer or a motorhome, for example, the bearing surface is located toward the roof and forms a part of the bottom of the air conditioning system, so to speak. The bearing surface does not have a flat or planar shape, but has several — at least two — fins on which the evaporator heat exchanger stands. An advantage of the fins is that they enhance cooling performance by preventing air from passing underneath the evaporator heat exchanger. Alternatively or complementarily, the fins cause such air to be directed into the evaporator heat exchanger from below. The fins thus increase the resistance for the air that could flow below the evaporator heat exchanger and/or act as components that guide the air. Furthermore, the interaction of the air with the evaporator heat exchanger causes drying of the air. The moisture thus removed from the air condenses and the condensed water collects below the evaporator heat exchanger. Here, the fins ensure that the condensed water drips down into the areas between the fins — that is, into the valleys. Moreover, the fins also provide the advantage that the undesirable air flowing along under the evaporator heat exchanger cannot absorb and carry off any condensed water, or only very little.
The following configurations relate to the bearing surface.
One example embodiment consists in that the fins are formed in such a way as to direct air below the evaporator heat exchanger into the evaporator heat exchanger. In this example embodiment, the fins thus not only cause the resistance for the air below the evaporator heat exchanger to be increased, but they also selectively direct the air into the evaporator heat exchanger. The direction of movement of the air is thus deflected in a targeted manner. This is preferably possible by the shaping of those flanks of the fins against which the air stream flows. Furthermore, to this end, the evaporator heat exchanger is preferably designed to be open toward the bearing surface so that the air can flow into it from below.
One example embodiment provides that the housing and the bearing surface are formed and matched to each other such that alternatively at least two evaporator heat exchangers having different depths can be fixed in the housing. In this example embodiment, it is possible to use one housing for different variants of the air conditioning system. In this case, the air conditioning systems differ at least with respect to the evaporator heat exchangers, which have different depths and therefore also have different cooling capacities. The depth in this case is defined as the extension along the direction in which the air is passed through the evaporator heat exchanger. Therefore, a greater depth also allows a higher cooling capacity.
One example embodiment consists in that tubes for carrying a refrigerant are arranged in the evaporator heat exchanger, and in that the tubes are arranged in at least two rows. In order to produce as large an effective surface as possible, the refrigerant is passed through a tube structure. The tubes are arranged in several and at least two rows one above the other, so that a meandering course is obtained for the coolant in each case. In one example embodiment, the tubes of the individual rows are connected to each other at the sides of the evaporator heat exchanger for the coolant.
In one example embodiment, the rows of tubes are arranged one behind the other in the direction of the air passing through the evaporator heat exchanger, so that each row involves a further interaction with respect to the cooling of the air. As the number of rows of tubes arranged one behind the other increases, the depth of the evaporator heat exchanger also increases.
One example embodiment consists in that an evaporator heat exchanger having a maximum depth can be fixed in the bearing surface, in that a maximum number of rows of the tubes is assigned to the maximum depth, and in that the number of fins is at least equal to the maximum number of rows of the tubes. In this example embodiment, the housing is adapted to receive a type of evaporator heat exchanger having a maximum depth. Other types that are shorter can also be accommodated accordingly. Except for the depth, the dimensions of the different types of evaporator heat exchangers are therefore alike. The maximum depth is associated with a maximum number of rows of tubes. Here, the number of fins is at least equal to the maximum number of rows. This implies that each row has one fin associated with it. In one example embodiment, this causes each fin to deflect the air toward the associated row of tubes. In one example embodiment, the number of fins is exactly the same as the maximum number of rows.
In one example embodiment, the fins are substantially identical in design. This simplifies manufacturing. In an alternative example embodiment, the fins are of different design. Here, consideration is given to the fact that the amount of air to be deflected decreases from fin to fin along the general direction of flow.
One example embodiment provides that the fins are oriented substantially perpendicular to a direction of air flow through the evaporator heat exchanger. In this example embodiment, the upper edges of the fins extend perpendicularly to the flow-through direction. In one example embodiment, the fins have a triangular cross-section, with the lateral flanks being curved in one example embodiment.
One example embodiment is that the bearing surface serves as a collecting pan for condensed water. The condensed water forms on the evaporator heat exchanger and drips down by gravity and therefore onto the bearing surface, which in this example embodiment thus also serves as a collecting pan. For this purpose and for draining off the condensed water, corresponding recesses for draining off are provided in one example embodiment.
According to a further example embodiment, provision is made that the air conditioning system includes a condenser heat exchanger, a condenser fan, and a housing, wherein the condenser heat exchanger transfers thermal energy of the air to be cooled to an external air, wherein the housing includes at least one air inlet and an air outlet for the external air, wherein the condenser fan introduces the external air into the housing via the air inlet and discharges it via the air outlet, and wherein the air outlet is designed such that the external air continues to move in as straight a line as possible after leaving the air outlet.
The thermal energy of the air to be cooled is first transferred to the coolant and then to the external air. The external air here originates, e.g., from the environment around the room the air of which is to be cooled by the air conditioning system. If the air conditioning system is, for example, a so-called roof-mounted air conditioning system, which is installed, e.g., on the roof of a travel trailer or a motorhome, the air in the interior of the travel trailer or motorhome is cooled and the heat is transferred to the ambient air around the travel trailer or motorhome as thermal energy. For this energy transfer, the condenser heat exchanger and the condenser fan are provided. The condenser heat exchanger carries the refrigerant and allows interaction with the external air in that the external air is passed through the condenser heat exchanger, absorbing heat from the refrigerant. The condenser fan provides for the movement of the external air into the housing of the air conditioning system and, after interaction with the condenser heat exchanger, for the movement out of the housing again. The housing has at least one air outlet, which is configured such that the external air continues to move in as straight a line as possible after leaving the air outlet and thus also the housing. This is intended to make sure that the kinetic energy of the heated external air is made use of for as long a distance as possible away from the housing. This in turn is intended to prevent exactly the heated external air from being sucked back in by the air conditioning system. This increases the effective power.
The following configurations refer to this condenser part of the air conditioning system, in which the external air serves to remove the heat.
One example embodiment provides that the housing has a plurality of air outlets, that the air outlets open on only one blow-out side of the housing, and that the air outlets open in a straight line and substantially parallel to each other. In this example embodiment, after passing through the condenser heat exchanger, the external air is directed out of the housing through a plurality of air outlets. Here, the air outlets are all configured such that the external air travels substantially only rectilinearly after leaving the air outlets. The air passages extend such that they open substantially parallel to each other. Therefore, the air streams passing through them are also each directed parallel to each other and away from the housing. This is also intended to prevent swirling and minimize the risk of heated external air being drawn in.
One example embodiment consists in that the air outlets commence radially around the condenser fan. The condenser fan has a substantially circular outer contour along which the blades of the fan carry the air outward. The air outlets start adjacent to this outer contour (or, depending on the example embodiment, in a plane offset therefrom).
One example embodiment provides that carrier components of the housing are located between the air outlets, and that the carrier components at least partially carry the condenser heat exchanger. In this example embodiment, the housing serves to stabilize the air conditioning system by having carrier components that are located between the air outlets and on which the condenser heat exchanger at least partially rests. Thus, there are sections between the air outlets that are designed to be sufficiently stable for this function. The carrier components also allow the air outlets to be made sufficiently narrow so that protection against reaching in is provided.
In one example embodiment, the housing has a plurality of air inlets, and the air inlets are connected with three intake sides of the housing. In one example embodiment, the housing has four sides and has an essentially rectangular basic shape. In this example embodiment, the external air enters the air conditioning system from three sides for the removal of heat. Preferably, these are an end face and the two longitudinal sides. In one example embodiment, the air inlets extend over almost the entire end face and project as close as possible to the end face on the longitudinal sides. In one example embodiment, the end face serves not only as the intake side, but also as the blow-out side.
One example embodiment provides that the housing has a plurality of air inlets and a plurality of air outlets, that the air inlets and the air outlets are located at different levels along a height of the air conditioning system, and that the level of the air inlets is above the level of the air outlets. In one example embodiment, the air inlets and air outlets considered herein with respect to the levels or planes are located on a common side of the housing, which is preferably a rear end face of the housing. The planes or levels should be understood to be perpendicular to a height of the air conditioning system here. This height profile results, for example, along the force of gravity in the installed state, so that, for example, one plane or level is higher than the other(s) relative to the bearing surface of the air conditioning system. The bearing surface is, for example, a roof of a travel trailer or a motorhome. The level of the air outlets is below the level of the air inlets here. In one example embodiment, the level of the air outlets is located as low as possible so that the external air is also expelled as close as possible to the roof or generally near the bearing surface of the air conditioning system.
One example embodiment consists in that the condenser heat exchanger has the shape of a capital letter “U”, and that the condenser fan is arranged within the U-shape. In this example embodiment, the condenser heat exchanger has a curved shape and comprises an inner area. In one example embodiment, the condenser fan is located in this inner area. In one example embodiment, the tip of the U faces the end face of the air conditioning system so that the two flanks of the U extend along the two longitudinal sides.
According to one example embodiment, pockets are located between the housing and the condenser heat exchanger, the pockets directing the external air towards the bottom of the U-shape of the condenser heat exchanger. This means that the pockets are larger cavities between the condenser heat exchanger and the internal structure of the housing. Or, in other words, there is room around the condenser heat exchanger for guiding external air. Here, the pockets in particular direct the external air towards the bottom of the U-shape, that is, towards that part of the letter U from which the two lateral legs branch off. The air guided to the base or tip (as alternative designations for bottom) of the U here is preferably the external air sucked in via the longitudinal sides. This also ensures that, as far as possible, no heated external air is returned to the air conditioning system. This applies, above all, in the context of the example embodiment in which the heated external air is blown out via the rear end face.
One example embodiment provides that the condenser heat exchanger is located downstream of the at least one air inlet, and that the condenser fan pulls the external air through the condenser heat exchanger. In one example embodiment, a plurality of air inlets are provided and the condenser heat exchanger extends along the air inlets and is preferably located behind the mouths of the air inlets.
In one example embodiment, only part of the structure of the air outlets is formed by the housing itself. The rest, and in particular the lower portions of the ducts of the air outlets, are formed in the installed state by the surface on which the air conditioning system is mounted. In this way, for example, a vehicle roof constitutes a boundary for the air outlets.
More specifically, there is a multitude of possibilities for configuring and further developing the air conditioning system according to the invention. In this regard, the description below of exemplary embodiments in conjunction with the drawings, in which:
For the refrigeration process, a compressor 2 compresses a gaseous refrigerant, which thus absorbs heat and is conveyed to a condenser 4 through a refrigerant pipe.
In the condenser 4, the heat of the refrigerant is released to the ambient air (or external air) from the environment around the room 100. In this process, the external air is taken in by means of a condenser fan 40 and, after interaction with the refrigerant, is blown out again in a condenser heat exchanger 41. As a result of the release of heat, the compressed refrigerant will condense.
The liquid refrigerant, which continues to be under high pressure, is expanded to a lower pressure in an expansion device 5, which is in the form of a restrictor, for example. In the process, the refrigerant cools down.
In the next step, the refrigerant reaches an evaporator 6, through which the air of the room 100 to be cooled is passed by means of an evaporator fan 60. In the process, the air transfers its heat to the refrigerant, which transitions to the gaseous state. The gaseous refrigerant eventually reaches the compressor 2 again, so that the cooling cycle can be continued.
The circuit can also be reversed so that the device 1 serves as a space heater.
The components described of the air conditioning system 1 are located in a housing 10 which — as shown, for example, in WO 2007/042065 A1 — is comprised of two shells, depending on the embodiment. Here, the housing 10 and the components are also configured and matched to one another such that the housing serves to fasten the components of the air conditioning system 10 by an interlocking fit.
The air conditioning system 1 has two heat exchangers 41, 61 and two fans 40, 60. The fans 40, 60 — in the functional portions of the condenser 4 and the evaporator 6, respectively — each cause air to be directed through the heat exchangers 41, 62 and to be heated or cooled in the process. In the following, the configurations of the two associated areas of the air conditioning system 1 (i.e., evaporator 6 as well as condenser 4) are described in detail and each also in reference to
In this context, one heat exchanger 61 may also be referred to as an inner or internal heat exchanger, since it cools the inner air, that is, the air, to be cooled, of the room 100. This heat exchanger 61 thus interacts with the inner air. The other heat exchanger 41 is used to interact with the external air by transferring the heat of the refrigerant to the external air. Therefore, this heat exchanger 41 may also be referred to as an outer or external heat exchanger.
The exemplary air conditioning system 1 of
The air conditioning system 1 not only effectuates cooling of the indoor air, but also drying. In the process, the moisture in the air accumulates as condensed water (an alternatively used term is condensate) and collects in particular at the evaporator heat exchanger 61.
The evaporator heat exchanger 61 shown in
Depending on the maximum cooling capacity, different numbers of rows of tubes 62 are provided. It can be seen in
The evaporator heat exchanger 61 stands upright in the housing 10 and the condensed water drips down by the force of gravity. At the base of the evaporator heat exchanger 61, the condensed water is then drained off using suitable geometries — not illustrated here — or, for example, by a pump.
The evaporator heat exchanger 61 is clamped in the housing 10 from above and below, and is thereby held in position by the housing 10. An identical enclosure — as can be seen in particular in
The (indoor) air to be cooled is moved from left to right — as indicated by the arrow in
In order to prevent, as far as possible, the condensed water from being entrained by the cooled air, the bearing surface 63 in the housing 10 below the evaporator heat exchanger 61 is specially shaped here (see
As can be seen, this does not involve a flat or planar bearing surface 63, but rather there are individual fins 64 which extend below and along the lower side of the evaporator heat exchanger 61. Located between the fins 64 are valleys in which condensed water can collect and flow off toward drainage openings not shown here. The height of the fins 64 or, correspondingly, the depth of the valleys, which thus serve as collecting pans for the condensed water, determines the amount of condensed water that can be collected. Draining from the valleys occurs, for example, by the action of gravity or by the action of, for example, a pump — also not shown here. As can be seen clearly in
The fin structure prevents air from incorrectly passing underneath the evaporator heat exchanger 61 on the side of the air inlet (on the left in each of
Furthermore, the fin structure deflects air that might still have moved to below the evaporator heat exchanger 61 in different directions again and again (up and down along the fins 64). This reduces or prevents air from flowing underneath the evaporator heat exchanger 61 and also has the effect of preventing condensed water from being entrained.
In this regard, the numbers and positions of the fins 64 in the illustrated variant are configured such that one fin 64 is located below each row of tubes 62. Each fin 64 directs the air back into the evaporator heat exchanger 61 and at the same time increases the resistance for the air flowing beneath the evaporator heat exchanger 61 and thus misdirected. If the condensed water drips down, it is carried toward the valleys, each of which is adjacent to a fin 64. Here there are four fins 64, so that an evaporator heat exchanger 61 having four rows of tubes 62 may also be received in the free space (see
The condensed water thus drips downward and collects in the valleys between the fins 64 of the bearing surface 63. Since the evaporator heat exchanger 61 stands on the fins 64, the condensed water can therefore not, or only to a very small extent, be entrained from a respective valley toward the evaporator fan 60 by the air flow.
The bulge 65 — protruding out toward the side of the evaporator heat exchanger 61 against which the air flows — projects into the space into which the indoor air to be cooled is guided to pass through the evaporator heat exchanger 61 (see the arrow in
As indicated in
It is further apparent from
The bulge 65 produces a partial narrowing of the space in front of the evaporator heat exchanger 61. The air enters this space from each side, so that on each of these two sides there is also the largest space between the bulge 65 as a distributor structure and the evaporator heat exchanger 61. The outer contour of the side of the evaporator heat exchanger 61 facing the bulge 65 is essentially given by a flat rectangular shape.
The position of the bulge 65 relative to the evaporator fan 60 can be seen, for example, with the aid of the inside of the upper half of the housing of
As can be seen in
The profile of the bulge 65 — here viewed along the height of the housing 10 and therefore in the installed state also along the earth’s gravitational pull — first constricts the upper space in front of the evaporator heat exchanger 61 to a very narrow area and then widens the area in a type of S-shape. The space in front of the lower part of the evaporator heat exchanger 61 is thus significantly larger and wider than the space in front of the upper part. The constriction in the upper area in the space in front of the evaporator heat exchanger 61 forces the air flowing in from the sides downward, as it were.
This shape of the bulge 65, which differs laterally and in its height profile, can be seen clearly in
The bulge 65 provides for a uniform velocity distribution of the air in front of the evaporator heat exchanger 61 and in this way improves the cooling behavior thereof, since there is a uniform flow through it. Another advantage is that the air volume is uniformly distributed and therefore the air flows uniformly through the evaporator heat exchanger 61 as well. This also improves the cooling performance. The air to be cooled is thus fanned out and distributed as far as possible over the entire side of the evaporator heat exchanger 61.
In
It is apparent from
In
Furthermore,
In one configuration — not shown here — there is no opening for the intake of external air at the rear end face 16, but only for the ejection of the external air that has passed through the condenser heat exchanger 41.
The shape of the pockets 45 is apparent from the upper side of the housing 10, which is shown in
At the upper end in the drawing here, which is the rear end face, the U-shaped profile of the condenser heat exchanger 41 and the space around it can be seen. The substantially rectangular shape of the housing 10 results in the pockets 45 around the bottom of the capital letter U of the condenser heat exchanger 41. The fins extend between the air intakes on the two longitudinal sides.
In
It is further apparent from
Altogether, the external air flows into the air conditioning system 1 from a position further away from the vehicle roof, passes through the condenser heat exchanger 41, and is then deflected to a lower position and blown out through the air outlet 43 in the vicinity of the vehicle roof.
In
It can be seen in
In
In the upper area — or rear area in the installed state — the fan carrier for the condenser fan 40 can be seen. Further air inlets 42 are located along the two longitudinal sides 15, which thus serve as intake sides 12 for the external air. In total, the air conditioning system 1 has air inlets 42 for the external air in its area facing away from the direction of travel on all three outer sides, which can thus be referred to as intake sides 12. The air inlets 42 (of which the individual ducts are visible in the view of
The heated air is blown out only through the end face 16 — the upper end face in the drawing in
In the illustrated configuration, eight air outlets 43 are provided, between which carrier components 44 are located. The condenser heat exchanger 41 rests on these carrier components 44 (see
As can be seen in
The underside of the housing 10 illustrated in
The air outlets 43 branch off with wide initial portions from the circular condenser fan 40, and then, after a portion which is as large and elongated as possible, open into the aforementioned tubular end portions. It can be seen that the air outlets 43 have a generally vortex-like shape. Alternatively, at least the inner portion around the condenser fan 40 may also be understood as having the shape of a snail shell. In this case, the air outlet 43 located on the right here has the longest extent. Here, the structure depends on the direction of rotation of the condenser fan 40.
In
It is also readily visible on this end face 16 of the housing 10 — which is the rear end face in the installed state — how the eight air outlets 43 open out in a straight line and parallel to each other, so that the expelled and heated external air is blown away as far as possible. The air is thus blown out each in the same direction.
The web-shaped carrier components 44 are located between the air outlets 43. The carrier components 44 bring about the further advantage that persons are prevented from reaching into the air outlets 43.
Number | Date | Country | Kind |
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10 2020 002 860.8 | May 2020 | DE | national |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2021/000034 | 4/7/2021 | WO |