Air conditioning system and method for dehumidifying air conditioning system

Abstract

The invention relates to an air-conditioning system (10), in particular for air-conditioning the interior of a motor vehicle, comprising a fan (14) for conveying sucked air through an air duct (16) and an evaporator (12) arranged in the air duct (16) for cooling the sucked air, a collection body (20) separate from the air channel (16) is arranged in the air channel (16) for collecting moisture (18) of the sucked air condensed on the evaporator (12), the sucked air being flowable through and / or bypassing the collection body (20) in a deactivated state of the evaporator (12). According to the invention, the discharge of condensate (18) occurring on the evaporator (12) can be improved by means of a collecting body (20) positioned in the air channel (16), such that a simple and efficient dehumidification of the air conditioning system (10) can be achieved.

Description

Technical Field

[0001] The invention relates to an air-conditioning system which can be used to air-condition the interior of a motor vehicle and to a method which can be used to dehumidify such an air-conditioning system. Background Art

[0002] DE 10 2005 022 208 A1 discloses that after the motor vehicle is switched off, the fan of the air conditioning system of the motor vehicle can continue to operate and that the air flow of the fan can be directed along the lowest part of the air duct of the air conditioning system in order to remove condensation water collected there from the evaporator of the air conditioning system.

[0003] There is always a need for simple and efficient dehumidification of air conditioning equipment. Summary of the invention

[0004] The object of the present invention is to propose measures which enable simple and efficient dehumidification of an air-conditioning device.

[0005] According to the invention, this object is achieved by an air conditioning device having the features of claim 1 and a method having the features of claim 9. Preferred embodiments of the invention are given in the dependent claims and the following description, which can each represent aspects of the invention individually or in combination.

[0006] One aspect of the present invention relates to an air conditioning device, which is particularly used for air conditioning the interior space of a motor vehicle, and has a fan for conveying sucked air through an air duct and an evaporator arranged in the air duct for cooling the sucked air, wherein a collecting body different from the air duct is arranged in the air duct for collecting moisture in the sucked air condensed on the evaporator, wherein when the evaporator is in an inactive state, the sucked air can flow through the collecting body and / or bypass the collecting body.

[0007] The fan can draw air from the environment, wherein the drawn air can be warm and humid depending on the ambient conditions. This causes the moisture of the air that is drawn and cooled on the evaporator to condense at the cold evaporator. Condensate can drip at the evaporator under the influence of gravity. The dripping condensate can be collected and at least temporarily stored by the collecting body. This can prevent the condensate from accumulating at the lowest part of the air channel. Here, the knowledge is used that the condensate accumulated at the lowest part of the air channel usually forms a very small surface, so that only a very small mass flow of the condensate can be discharged by the air flow provided by the continued operation of the fan. In addition, the air channel is usually designed to minimize the flow resistance, resulting in the flow conditions at the channel wall of the air channel being quite unfavorable for receiving the condensate.

[0008] By means of a collecting body separated from the air channel, the condensate can be collected spaced apart from the channel wall of the air channel, so that the condensate can flow to the condensate under more favorable flow conditions. The collecting body can be located at the evaporator. Preferably, the collecting body is spaced apart from the evaporator so that the condensate drips from the evaporator through the heat-insulating air gap between the evaporator and the collecting body and can fall on the collecting body. Particularly preferably, the collecting body can be designed so that the condensate is distributed on a larger surface than the surface formed in the case of a partially circular groove. Therefore, the collecting body enables the collected condensate to contact the air flow generated by the fan on a significantly larger surface and under significantly better flow conditions, thereby significantly increasing the mass flow of the incoming air flow, and the air flow is more loaded with the received condensate. This in turn enables the air conditioning device, especially the air channel, to dry faster, and the fan requires less power. The energy efficiency for dehumidifying the air conditioning device is thereby improved. Since it is only necessary to position the appropriately designed and shaped collecting body at a location where the air that can be sucked flows well, more precisely, around, especially below the evaporator, energy saving can be achieved very simply in terms of structure. For example, the collecting body can be mounted in an easily replaceable manner on a support extending into the interior of the air duct, so that in particular multiple surfaces of the collecting body can be flowed around. The collecting body positioned in the air duct can improve the drainage of condensate that occurs at the evaporator, thereby achieving simple and efficient dehumidification of the air conditioning system.

[0009] The air conditioning device can have a closed cooling circuit in particular, in which the evaporator is arranged. The cooling circuit can have a compressor in order to circulate a refrigerant in the cooling circuit. The refrigerant compressed by the compressor can be cooled in a heat exchanger or a cooler, in particular a precooler, of the motor vehicle and then supplied to the evaporator via an expansion valve. The evaporated refrigerant can then be supplied to the compressor again and liquefied. The fan can guide the sucked air along the surface of the evaporator, thereby cooling the sucked air. The cooled air can then be guided into the interior of the motor vehicle.

[0010] The air channel can be led from an inlet connected to the environment via a fan to at least one air outlet. An air outlet leading to the interior of the motor vehicle can be provided in order to air condition the interior with the aid of conditioned air. The air channel can also be led to another air outlet connected to the environment in order to discharge unnecessary air and to discharge condensate carried by the sucked air, thereby dehumidifying the air conditioning device. Preferably, a switching mechanism is provided, by which the mass flow and / or the flow direction of the air flow introduced into the interior can be adjusted. In particular, it can be provided that the air flow sucked by the fan is guided to different flow paths with the aid of at least one switching mechanism.

[0011] The collecting body has, in particular, a plurality of storage holes for temporarily storing condensed moisture. The shape of the collecting body can be non-uniform to form the storage holes and can differ greatly from the shape of the housing. This enables the collected condensate to be distributed in a plurality of holes. Due to the surface tension of the condensate, the water received in the corresponding holes can be retained in the holes, thereby preventing the condensate from dripping to the bottom of the air channel. At the same time, a large total area can be formed for the collected condensate by the holes, thereby improving the phase change process from the holes to the air flow generated by the fan and achieving a large amount of condensate loaded on the air flow.

[0012] Preferably, the collecting body is designed as a sponge and / or foam. The collecting body can be made of natural and / or synthetic materials. For example, the collecting body is designed as an aluminum foam. Thus, the collecting body can easily form a large number of pores and / or provide a large surface for the collected condensate.

[0013] Particularly preferably, the sucked air can flow through the lower side of the collecting body pointing downward in the direction of gravity and / or through the upper side pointing downward in the direction of gravity and / or through at least one side pointing essentially in the horizontal direction. The collecting body can be positioned, in particular, essentially centrally in the flow cross section of the air flow provided by the fan. Since the collecting body is preferably not only flowed through on one side but can flow around surfaces facing away from one another, particularly large condensate mass flows can be transferred from the collecting body to the air flow.

[0014] The fan is coupled to the evaporator with a predetermined delay time, in particular via a timer relay, so that the fan is started with a delay after the delay time has elapsed after the evaporator has been deactivated. This prevents the fan from actively continuing to operate for a long time after the normal operation has ended. On the contrary, the delay time can be waited for so that the surface of the evaporator is sufficiently close to the ambient temperature, so that when the fan draws in unconditioned air, there is no need to worry about the formation of large amounts of condensation products on the surface of the evaporator. The condensate can remain in the collector for the length of the delay time. This can minimize the operating time of the fan required for dehumidifying the air conditioning system after the delay time has expired, and thus also minimize the energy consumption associated with it.

[0015] Preferably, the fan can be switched off depending on the water load of the collecting body and / or after a predetermined drying time has elapsed. The fan can be operated until the humidity sensor indicates a sufficiently low condensate load of the collecting body and thus signals that the air conditioning device has been sufficiently dehumidified. The fan can thus be switched off in response to a measurement signal of the humidity sensor. Additionally or alternatively, a predetermined drying time can be waited for until the fan is switched off. In particular, an unnecessarily long and inefficient operation of the fan can be avoided when the expected degree of dryness of the collecting body measured by the humidity sensor cannot be achieved within the drying time under particularly warm and humid weather conditions.

[0016] Particularly preferably, the collecting body is arranged in a bypass channel which can be closed by the rest of the air duct. This makes it possible that in normal air-conditioning operation of the air conditioning system, the air sucked in by the fan flows around the evaporator but not around the collecting body. This makes it possible to avoid an undesired accumulation of moisture in the air directed to the interior of the motor vehicle. When the evaporator of the air conditioning system and / or the motor vehicle are switched off, the air sucked in by the fan can be directed into the bypass channel, wherein the sucked in air preferably preferably passes by the evaporator which may still be very cold. In the dehumidification operation of the air conditioning system, the air outlet leading to the interior can be closed so that the particularly humid air flowing around the evaporator can not enter the interior but be discharged directly into the environment.

[0017] The collecting body is positioned in particular at a distance from the channel wall of the air channel. This makes it possible to avoid contact of condensate with the channel wall of the air channel, thereby also avoiding wear effects due to the presence of water, such as water corrosion of metal components. In addition, it is possible to achieve that the sucked air flows around the evaporator over the largest possible area.

[0018] Another aspect of the invention relates to a method for operating an air conditioning system, which can be designed and modified as described above, wherein after deactivating the evaporator, in particular after the motor vehicle is shut down, the fan is still operated in order to dry the collecting body loaded with condensed moisture by means of air sucked in by the fan and to discharge the condensed moisture from the air conditioning system. The method can be designed and modified in particular as described above with reference to the air conditioning system. The collection body positioned in the air duct can improve the discharge of condensate generated at the evaporator, thereby achieving simple and efficient dehumidification of the air conditioning system.

[0019] Preferably, the fan is started after a predetermined delay time from deactivation of the evaporator and / or from shutdown of the motor vehicle. This prevents the fan from actively continuing to run after normal operation has ended. Instead, the delay time can be waited for the surface of the evaporator to be sufficiently close to the ambient temperature so that when the fan draws in unconditioned air, there is no need to worry about large amounts of condensation products on the surface of the evaporator. The condensate can remain in the collector for the length of the delay time. This minimizes the operating time of the fan required for dehumidifying the air conditioning system after the delay time has expired, and thus also the energy consumption associated with it. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention is exemplarily described below by means of preferred embodiments with reference to the accompanying drawings, wherein the features presented below may represent various aspects of the present invention individually and in combination. Among them:

[0021] Figure 1 A schematic cross-sectional view of a portion of an air conditioning system is shown. DETAILED DESCRIPTION

[0022] exist Figure 1 The air conditioning device 10, which is only partially shown in FIG. 1 , can be used to air condition the interior of a motor vehicle. The air conditioning device 10 has an evaporator 12 in which a refrigerant can evaporate to generate cold. In normal air-conditioning operation of the air conditioning device 10, an air flow sucked from the environment by a fan 14 through an air channel 16 can be cooled, and the air flow then reaches the interior of the motor vehicle. Condensate 18 generated on the evaporator 12 can drip downwards on the surface of the evaporator 12 due to gravity and fall onto a collecting body 20, which is designed as a sponge or metal foam, for example. The collecting body 20 can collect the condensate 18 and store it at least temporarily, especially in the pores of the collecting body 20. The collecting body 20 is spaced apart from the channel wall 24 of the bypass channel 26 connected to the rest of the air channel 16 by means of a bracket 22 and is positioned substantially centrally in the flow cross section of the bypass channel 26 of the air channel 16.

[0023] When the motor vehicle and / or the evaporator 12 is shut down and deactivated, the fan 14 can be switched on again after a delay time which can be predetermined by means of a timer relay 28. During the delay time, the bypass channel 26 can be opened, for example, by means of at least one switching flap 30 of a switching mechanism, and preferably a large part of the evaporator 12 is separated from the surrounding air flow. In dehumidification operation, the air flow can flow around the collecting body 20 over the largest possible area, so that as much condensate 18 as possible can be taken up from the collecting body 20 and discharged to the environment. The fan 14 can be switched off automatically after a predetermined drying time and / or in the case of sufficiently low humidity or water loading of the collecting body 20, which can be measured by a humidity sensor 32.

Claims

1. An air conditioning device (10), in particular for air conditioning the interior of a motor vehicle, comprising a fan (14) for conveying sucked air through an air duct (16) and an evaporator (12) arranged in the air duct (16) for cooling the sucked air, characterized in that: A collecting body (20) different from the air channel (16) is arranged in the air channel (16) for collecting moisture (18) of the sucked air condensed on the evaporator (12), wherein, when the evaporator (12) is in an inactive state, the sucked air can flow through the collecting body (20) and / or around the collecting body (20).

2. The air conditioning device (10) according to claim 1, characterized in that: The collecting body (20) has a plurality of storage holes for temporarily storing the condensed moisture (18).

3. The air conditioning device (10) according to claim 1 or 2, characterized in that: The collecting body (20) is designed as a sponge and / or foam.

4. The air conditioning device (10) according to any one of claims 1 to 3, characterized in that: The sucked air can flow through a lower side of the collecting body (20) pointing downward in the direction of gravity and / or an upper side pointing downward in the direction of gravity and / or at least one side surface pointing essentially in the horizontal direction.

5. The air conditioning device (10) according to any one of claims 1 to 4, characterized in that: The fan (14) is coupled to the evaporator (12) via a timing relay (28) at a predetermined delay time, so that after the evaporator (12) is deactivated, the fan (14) is started with a delay after the delay time has elapsed.

6. The air conditioning device (10) according to claim 5, characterized in that: The fan (14) can be switched off depending on the water load of the collecting body (20) and / or after a predetermined drying time has elapsed.

7. The air conditioning device (10) according to any one of claims 1 to 6, characterized in that: The collecting body (20) is arranged in a bypass channel (26) which can be closed by the rest of the air channel (16).

8. The air conditioning device (10) according to any one of claims 1 to 7, characterized in that: The collecting body (20) is positioned at a distance from a channel wall (24) of the air channel (16).

9. A method for operating an air conditioning system (10) according to any one of claims 1 to 8, wherein: After deactivation of the evaporator (12), in particular after the motor vehicle is shut down, the fan (14) is operated in order to dry the collecting body (20) loaded with condensed moisture (18) with the aid of air sucked in by the fan (14) and to discharge the condensed moisture (18) from the air conditioning device (10).

10. The method according to claim 9, characterized in that The fan (14) is not started until after a predetermined delay time from the deactivation of the evaporator (12) and / or the shutdown of the motor vehicle.

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