Air conditioning device

Abstract

An air conditioning device for a motor vehicle, comprising an air inlet duct (21) with a supply air inlet opening (22) so that outside vehicle air can flow through the supply air inlet opening (22) into the air inlet duct (21), further comprising an air conditioning system (23), wherein an air supply duct (8) to the air conditioning system (23) is fluidly connected to the air inlet duct (21), wherein the air conditioning device comprises an air extraction duct (24) with an exhaust air inlet opening (25) so that inside vehicle air can flow through the exhaust air inlet opening (25) into the air extraction duct (24), wherein the air extraction duct (24) has an exhaust air outlet opening (26) so that the extracted inside air can be discharged through the air extraction duct (24) and the exhaust air outlet opening (26), comprising a rotary heat exchanger (1) arranged toin the operating state of the rotary heat exchanger (1), to carry out a heat exchange between the air inlet duct (21) and the air extraction duct (24), wherein an exhaust air fan (5) is arranged in the air extraction duct (24) in order to suck the vehicle interior air through the exhaust air inlet opening (25) into the air extraction duct (24), characterized in that a control unit is designed to activate the exhaust air fan (5) when a vehicle door is closed, so that vehicle interior air is automatically sucked out when the door is closed and thus an overpressure in the vehicle cabin is counteracted.

Description

Field of the invention

[0001] The present invention relates to an air conditioning device for a motor vehicle and a motor vehicle with such an air conditioning device. State of the art

[0002] Common air conditioning systems in motor vehicles use air conditioning to condition the interior air. Their primary purpose is to cool the air in a vehicle. However, air conditioning systems can generally also be used to change the humidity, filter out air constituents, or, for example, heat the air. Air conditioning systems typically use a refrigerant circuit to operate, with the refrigerant being processed, for example, via electrical heating / cooling devices and / or compressors. When an air conditioning system is in operation, fresh air is typically drawn in from outside the vehicle and fed into the vehicle interior in a conditioned state.

[0003] The treated air from the vehicle interior is typically released back into the vehicle's environment via a rear vent. The energy used to treat the interior air, for example, in the form of heat, is usually lost with the released air.

[0004] JP 2006 240 573 A discloses a device wherein a moisture absorption rotor is rotatably mounted above an air intake duct for introducing air into a cabin, and a regeneration duct is arranged for discharging the air to the outside of the vehicle. An absorbent material is applied to the surface of the moisture absorption rotor, allowing air to flow through it. The air introduced into the air intake duct by a first fan is dehumidified as it passes through the moisture absorption rotor and is then introduced into the interior after being heated to a suitable temperature by a heat exchanger for cooling and a heat exchanger for heating.The air introduced into the regeneration duct by a second fan is heated by the heat exchanger and then, after removing the absorbed moisture as it passes through the moisture absorption rotor, is discharged to the exterior of the vehicle. Summary of the invention

[0005] It is an object of the invention to provide an air conditioning device for a motor vehicle and a motor vehicle with such an air conditioning device, wherein energy losses during the conditioning of vehicle interior air by the air conditioning device are reduced.

[0006] The problem is solved by an air conditioning device for a motor vehicle having the features of claim 1.

[0007] The air conditioning device comprises an air inlet duct with a supply air inlet opening so that vehicle outside air can flow through the supply air inlet opening into the air inlet duct, further comprising an air conditioning system, wherein an air supply duct to the air conditioning system is fluidly connected to the air inlet duct, wherein the air conditioning device comprises an air extraction duct with an exhaust air inlet opening so that vehicle interior air can flow through the exhaust air inlet opening into the air extraction duct, wherein the air extraction duct has an exhaust air outlet opening so that the extracted interior air can be discharged through the air extraction duct and the exhaust air outlet opening, comprising a rotary heat exchanger which is arranged to carry out a heat exchange between the air inlet duct and the air extraction duct in the operating state of the rotary heat exchanger, wherein an exhaust air fan is arranged in the air extraction duct,to suck the vehicle interior air through the exhaust air inlet opening into the air extraction duct, wherein a control unit is configured to activate the exhaust air fan when a vehicle door is closed, so that vehicle interior air is automatically extracted when the door is closed, thus counteracting overpressure in the vehicle cabin.

[0008] According to the invention, an air conditioning device thus uses an air conditioning system to condition the vehicle's interior air, which is supplied with air via an air inlet opening, an air inlet duct, and an air supply duct. The air inlet duct and the air supply duct do not have to be structurally separated from one another, but can, for example, also be formed by a single duct. In addition to this air inlet duct, the air conditioning device also uses a duct for removing air, namely the air from the vehicle's interior. The interior air is removed via an exhaust air inlet opening, an air extraction duct, and an exhaust air outlet opening.

[0009] According to the invention, an air conditioning device comprises a rotary heat exchanger which is arranged to carry out a heat exchange between the air inlet duct and the air extraction duct in the operating state of the rotary heat exchanger, i.e. when the rotor of the rotary heat exchanger is running.

[0010] This type of heat exchange simultaneously preconditions the air supply to the air conditioning system, thereby reducing the energy required for a vehicle's air conditioning. Furthermore, the temperature, humidity, and air quality inside the vehicle can be improved. Rear ventilation can ideally be eliminated entirely, thereby also improving the acoustics in the vehicle. Energy losses caused by rear ventilation can thus be reduced. For example, dry air can be reduced during heating mode, the energy required for dehumidification during cooling mode can be reduced, and air quality can be improved by reducing the amount of recirculated air during cooling mode. This results in an overall reduction in the energy required for a vehicle's air conditioning, while simultaneously improving air quality and comfort.

[0011] According to the invention, an exhaust air fan is arranged in the air extraction duct in order to suck the vehicle interior air through the exhaust air inlet opening into the air extraction duct.

[0012] Further developments of the invention are specified in the dependent claims, the description and the accompanying drawings.

[0013] Preferably, the air inlet duct and the air extraction duct are arranged adjacent to one another in the region of the rotary heat exchanger. The rotor of the rotary heat exchanger preferably covers the air inlet duct and the air extraction duct. Preferably, the entire cross-section of the air inlet duct and the entire cross-section of the air extraction duct extend through the rotor of the rotary heat exchanger. Preferably, the diameters of the air inlet duct and the air extraction duct in the region of the rotary heat exchanger are approximately the same. The rotor center of the rotary heat exchanger is preferably located midway between the cross-sections of the air inlet duct and the air extraction duct.

[0014] A supply air fan is preferably arranged in the air inlet duct in order to convey the vehicle's outside air through the air inlet duct to an interior opening of the air inlet duct.

[0015] Preferably, a flap is arranged at the supply air inlet and / or the exhaust air outlet to selectively close and open the supply air inlet and / or the exhaust air outlet. Particularly preferably, a common flap is arranged for selectively opening and closing the supply air inlet and the exhaust air outlet. The supply air inlet and the exhaust air outlet can be arranged directly next to each other or as a single opening.

[0016] Preferably, a control unit is configured to control the rotor of the rotary heat exchanger, i.e., to at least switch the rotor of the rotary heat exchanger on or off, preferably also to control its speed. In addition to controlling the speed of the rotor of the rotary heat exchanger, the control unit is preferably also configured to control the two fans in order to control the required volume flows for the supply and exhaust air.

[0017] An air filter is preferably arranged in the air inlet duct to filter the supply air.

[0018] Preferably, the supply air inlet opening and the exhaust air outlet opening are arranged in a bulkhead of the motor vehicle, i.e. on the front side of the vehicle.

[0019] The motor vehicle preferably does not have a rear vent. Forced ventilation of the vehicle is preferably achieved exclusively through the air extraction duct and the exhaust air outlet. Short description of the drawing

[0020] The invention is described below by way of example with reference to the drawing. Fig. is a schematic representation of an air conditioning device according to the invention in a motor vehicle. Detailed description of the invention

[0021] The figure shows an air conditioning device according to the invention in a motor vehicle, wherein only the front wall 10 of the motor vehicle can be seen.

[0022] The air conditioning device comprises an air inlet duct 21 with a supply air inlet opening 22 in the front wall 10 of the motor vehicle, so that vehicle outside air can flow through the supply air inlet opening 22 into the air inlet duct 21.

[0023] The air conditioning device further comprises an air conditioning system 23, wherein an air supply duct 8 to the air conditioning system 23 is fluidly connected to the air inlet duct 21.

[0024] The air conditioning device also comprises an air extraction duct 24 with an exhaust air inlet opening 25 so that vehicle interior air can flow from the interior of the motor vehicle through the exhaust air inlet opening 25 into the air extraction duct 24, wherein the air extraction duct 24 has an exhaust air outlet opening 26 so that the extracted interior air can be discharged through the air extraction duct 24 and the exhaust air outlet opening 26 into the environment of the motor vehicle.

[0025] Finally, according to the invention, the air conditioning device comprises a rotary heat exchanger 1 which is arranged to carry out a heat exchange between the air inlet duct 21 and the air extraction duct 24 in the operating state of the rotary heat exchanger 1.

[0026] The air inlet duct 21 and the air extraction duct 24 are arranged adjacent to one another in the region of the rotary heat exchanger 1, and the rotor of the rotary heat exchanger 1 covers the air inlet duct 21 and the air extraction duct 24. The diameters of the air inlet duct 21 and the air extraction duct 24 are approximately the same in the region of the rotary heat exchanger 1, so that half the diameter of the rotor of the rotary heat exchanger 1 covers the air inlet duct 21 and the air extraction duct 24.

[0027] An exhaust air fan 5 is arranged in the air extraction duct 24 in order to suck the vehicle interior air through the exhaust air inlet opening 25 into the air extraction duct 24.

[0028] An air supply fan 6 is arranged in the air inlet duct 21 to convey the vehicle's outside air through the air inlet duct 21, into an interior of the motor vehicle and to the air supply duct 8 to the air conditioning system 23.

[0029] A common flap 7 is arranged at the supply air inlet opening 22 and the exhaust air outlet opening 26 in order to be able to selectively close and open the supply air inlet opening 22 and the exhaust air outlet opening 26 and thus to be able to switch between a supply air operation and a recirculation air operation of the air conditioning device.

[0030] An air filter 9 is arranged as a filter unit in the air inlet duct 21.

[0031] The supply air inlet opening 22 and the exhaust air outlet opening 26 are located in a bulkhead 10 at the front of the motor vehicle. The motor vehicle does not have a rear ventilation system.

[0032] The system of rear ventilation previously common in motor vehicles can be completely replaced by the solution according to the invention through an opening in the front wall 10 and the energy potential of the air in the vehicle interior can be recovered by the rotary heat exchanger 1.

[0033] For this purpose, an opening can be created in the area of ​​the bulkhead 10, similar to those used in other vehicles, to draw in fresh air for ventilation in the vehicle interior. However, this opening is divided into two areas: a supply air area and an exhaust air area. To remove the air from the interior and out of the vehicle, a dedicated fan, exhaust air fan 5, is installed. Its task is to automatically extract the exhaust air from the interior when the door is closed, thus counteracting excess pressure in the vehicle cabin, and to draw it through a heat exchanger, rotary heat exchanger 1, to force energy release via rotary heat exchanger 1.Preferably, a vehicle with an air conditioning device according to the invention does not have a flap that is usually installed in the rear of the vehicle, which automatically ensures pressure equalization when the doors are closed and thereby disadvantageously loses the energy contained in the vehicle interior air.

[0034] The rotary heat exchanger 1 is a rotary heat exchanger consisting of individual aluminum sheets in both flat and corrugated designs. This heat exchanger is equipped with a gear ring driven by a drive motor 3. The rotary heat exchanger 1 has a running surface on its circumference that serves to support the heat exchanger in the housing 4. The housing 4 serves to mount the components and guide the air. The drive motor 3 is adjustable in its drive speed and can thus adjust the rotational speed of the rotary heat exchanger 1 as required.

[0035] These requirements for the rotary heat exchanger can be, for example: temperature difference between outside and inside, required volume flow for air conditioning, moisture recovery or avoidance of the inside / outside air.

[0036] On the supply air side, there is also a blower, supply air fan 6, which is used in a conventional manner to supply the interior with fresh air. However, in this case, this also has the task of forcing the air drawn in from the outside of the vehicle through the rotary heat exchanger 1. As it flows through the rotary heat exchanger 1, the outside air is adapted to the desired conditions in the interior, thus reducing the load on the air conditioning system 23. The fresh air can be heated, cooled, dehumidified, and / or humidified.

[0037] The pre-conditioned fresh air thus contributes to energy savings in the entire vehicle.

[0038] For the additional fan on the exhaust air side, exhaust air fan 5: The exhaust fan 5 is controlled by the parameters of the air conditioning system 23 (HVAC) and has the task: 1.) To ensure constant pressure conditions in the vehicle during operation. Here, it can take over the role of the missing rear ventilation. 2.) To ensure ideal airflow to the rotary heat exchanger 1 on the exhaust air side. The available surface area of ​​the rotary heat exchanger 1 should be utilized to its maximum. 3.) When the door is closed, the exhaust air fan 5 is responsible for taking over the function of the missing rear ventilation and creating negative pressure and pleasant closing comfort for the vehicle occupants through adapted suction power.

[0039] Description of operating states: Basically, the functionality of the air conditioning device does not change between the different operating states, since the heating and cooling process always remains the same, as described below. 1.) Operating condition at, for example, outside temperature -10°C, low humidity inside and outside:

[0040] When heating, the temperature inside is higher than the outside temperature and the fins in the extract air zone are heated up. The extract air from the interior transfers energy and moisture to the fins coming from the cold air zone and is cooled on its way through the rotary heat exchanger 1. The cold fresh air from the supply air zone is pressed through the heated rotary heat exchanger 1 by the supply air fan 6 and absorbs energy and moisture from the fins on its way. The fresh air is thus preheated and humidified. A differential pressure sensor monitors for icing. If cross-sections become blocked due to icing, the speed can be briefly reduced. This defrosts and evaporates any ice that has already formed on the extract air side, and prevents or reduces excessive cooling of the rotary heat exchanger 1 and the icing of the cross-sections. 2.) Operating condition at, for example, outside temperature +18°C:

[0041] In this case, no cooling or heating is required, as sufficient waste heat is available to maintain the set interior temperature. Only the two fans, supply air fan 6 and exhaust air fan 5, are in operation, while rotary heat exchanger 1 remains stationary. No energy is required to rotate rotary heat exchanger 1. The same applies in recirculation mode. Here, rotation of rotary heat exchanger 1 is omitted. However, additional requirements such as cleaning or defrosting may necessitate rotation of rotary heat exchanger 1. 3.) Operating condition at, for example, outside temperature +30°C, high humidity outside:

[0042] In this case, the interior must be cooled by the air conditioning system (HVAC). For this purpose, the air drawn into the supply air area is cooled by the cooled fins of the rotary heat exchanger (1) from the exhaust air area. The rotary heat exchanger (1) transports the absorbed energy from the supply air to the exhaust air area and transfers this energy to the exhaust air. The moisture condensed in the supply air area is transported by the rotary heat exchanger (1) to the exhaust air area, where it evaporates again with dry exhaust air and thus does not reach the air conditioning system (HVAC). This allows for additional energy savings. List of reference symbols 1 rotary heat exchanger 3 Drive motor 4 housings 5 exhaust fans 6 supply air fans 7 flap 8 Air supply duct 9 air filters 10 Front wall 21 Air intake duct 22 Supply air inlet opening 23 Air conditioning 24 Air extraction duct 25 Exhaust air inlet opening 26 Exhaust air outlet opening

Claims

[1] Air conditioning device for a motor vehicle, comprising an air inlet duct (21) with a supply air inlet opening (22) so that vehicle outside air can flow through the supply air inlet opening (22) into the air inlet duct (21), further comprising an air conditioning system (23), wherein an air supply duct (8) to the air conditioning system (23) is fluidly connected to the air inlet duct (21), wherein the air conditioning device comprises an air extraction duct (24) with an exhaust air inlet opening (25) so that vehicle inside air can flow through the exhaust air inlet opening (25) into the air extraction duct (24), wherein the air extraction duct (24) has an exhaust air outlet opening (26) so that the extracted inside air can be discharged through the air extraction duct (24) and the exhaust air outlet opening (26), comprising a rotary heat exchanger (1) which is designed to is arranged,in the operating state of the rotary heat exchanger (1), to carry out a heat exchange between the air inlet duct (21) and the air extraction duct (24), wherein an exhaust air fan (5) is arranged in the air extraction duct (24) in order to suck the vehicle interior air through the exhaust air inlet opening (25) into the air extraction duct (24), , characterized by that a control unit is designed to activate the exhaust air fan (5) when a vehicle door is closed, so that vehicle interior air is automatically extracted when the door is closed and thus overpressure in the vehicle cabin is counteracted. [2] Air conditioning device according to claim 1, characterized bythat the air inlet duct (21) and the air extraction duct (24) are arranged adjacent to one another in the region of the rotary heat exchanger (1) and the rotor of the rotary heat exchanger (1) covers the air inlet duct (21) and the air extraction duct (24), wherein preferably the diameters of the air inlet duct (21) and the air extraction duct (24) in the region of the rotary heat exchanger (1) are approximately the same size. [3] Air conditioning device according to at least one of the preceding claims, characterized by that a supply air fan (6) is arranged in the air inlet duct (21) in order to convey the vehicle's outside air through the air inlet duct (21) to an interior opening of the air inlet duct (21). [4] Air conditioning device according to at least one of the preceding claims, characterized bythat a flap (7) is arranged at the supply air inlet opening (22) and / or at the exhaust air outlet opening (26) in order to be able to selectively close and open the supply air inlet opening (22) and / or the exhaust air outlet opening (26), preferably a common flap (7) for selectively closing and opening the supply air inlet opening (22) and the exhaust air outlet opening (26) together. [5] Air conditioning device according to at least one of the preceding claims, characterized by that the control unit is designed to control the rotor of the rotary heat exchanger (1), in particular to control it at a variable speed. [6] Air conditioning device according to at least one of the preceding claims, characterized by that an air filter (9) is arranged in the air inlet duct (21). [7] Motor vehicle with an air conditioning device according to at least one of the preceding claims, wherein the supply air inlet opening (22) and the exhaust air outlet opening (26) are arranged in an end wall (10) of the motor vehicle. [8] Motor vehicle according to claim 7, characterized by that the vehicle does not have rear ventilation.

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