Abstract:
A method for controlling an air-conditioning device in a motor vehicle includes the air-conditioning device conveying an air flow into a vehicle interior of the motor vehicle through at least one air outlet opening which is arranged on a lower side of an operating element designed to operate at least one device of the motor vehicle. A detection device detects and signals, by using a detection signal, if a user&#39;s hand is moved toward the operating element in order to actuate the operating element and/or if the operating element is actuated. The air-conditioning device then reduces and/or diverts the air flow.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a U.S. national stage of International Application No. PCT/EP2014/003027, filed on Nov. 12, 2014 and claims the priority benefit thereof. The International Application claims the priority benefit of German Application No. 10 2013 019 197.1 filed on Nov. 15, 2013. Both the International Application and German Application are incorporated by reference herein in their entirety. 
     
    
     BACKGROUND 
       [0002]    Described below is a method for controlling an air-conditioning device in a motor vehicle. In this case, the air-conditioning device is configured in a special manner to the effect that an air outlet opening, through which an air flow is blown into a vehicle interior of the motor vehicle, is arranged on a lower side of an operating element which can be used by a user to operate at least one device of the motor vehicle. In particular, the operating element may include a touchscreen which is arranged on a dashboard of the motor vehicle. 
         [0003]    When positioning a touchscreen in a motor vehicle, it is necessary to find a compromise between readability and reachability. The touchscreen must be arranged high enough in order to allow the display contents to be viewed by the driver during a journey with an only slight aversion of his gaze from the traffic situation. On the other hand, the touchscreen must also be able to be easily reached by the hand in order to carry out an operating action, that is to say it must not be arranged too high or too far away from the driver. An ideal position is generally that location at which the adjustable directional air vents or air-conditioning outlets are arranged in the dashboard. The air-conditioning outlets have an outlet opening through which the air-conditioning device of the motor vehicle blows an air flow into the vehicle interior of the motor vehicle. In other words, the touchscreen and the adjustable directional air vents provided centrally in the motor vehicle compete for the same installation space when designing a motor vehicle. The adjustable directional air vents are usually situated above or laterally beside the touchscreen. If the adjustable directional air vents are situated to the side of the touchscreen, the width of the touchscreen is restricted. If the adjustable directional air vents are situated above the touchscreen, the installation height of the touchscreen is restricted. 
         [0004]    However, the third solution, namely arranging the touchscreen above the adjustable directional air vents, is avoided nowadays since the user&#39;s hand is inevitably unpleasantly exposed to the air flow emerging from the air outlet opening while operating the touchscreen. This problem is generally present when designing a motor vehicle whenever an operating element, for example a touchscreen, has to be arranged above an air outlet opening of an air-conditioning device. 
         [0005]    DE 10 2008 018 397 A1 discloses a method for controlling air-conditioning of an interior of a motor vehicle. According to the document, an item of state information relating to a body part of a vehicle occupant of the motor vehicle is determined and an air outflow from the air-conditioning is adjusted on the basis of a comfort criterion to be complied with and the acquired state information relating to the body part. This avoids the air flow which is blown in being unpleasantly blown into the vehicle occupant&#39;s face. 
         [0006]    DE 10 2010 018 140 A1 describes a temperature adjusting apparatus for a motor vehicle, which has an integrated display. 
         [0007]    DE 10 2006 009 303 A1 discloses a method for air-conditioning a motor vehicle, in which the occupant does not experience any direct incident flow. 
         [0008]    DE 10 2012 003 311 A1 discloses a motor vehicle in which at least one parameter of a sitting position is read in and a ventilation temperature and/or an air distribution in the motor vehicle can be controlled on the basis of this parameter. 
       SUMMARY 
       [0009]    Described below is an arrangement of an operating element and an air outlet opening of an air-conditioning device in a motor vehicle, in which the operating element is arranged above the air outlet opening of the air-conditioning device. 
         [0010]    The method described herein makes it possible to arrange an air outlet opening or a plurality of air outlet openings of an air-conditioning device on a lower side of an operating element. As a result, the operating element can have any desired configuration to the sides and toward the top without the at least one air outlet opening being in the way. The operating element itself need not necessarily have anything to do with the air-conditioning device. It may be an operating element designed to operate at least one other device of the motor vehicle. In particular, it may be the described touchscreen which can be used to operate an infotainment system of the motor vehicle, for example. In connection with the disclosure, a touchscreen can be understood as meaning a touch-sensitive screen, that is to say a screen which has, on its display surface, a sensor matrix which is used to detect touching or an approach or a pressure of a finger on the basis of the location. 
         [0011]    In order to avoid the described disadvantage of the operating hand being in the air flow when operating the operating element, the method described herein provides for a detection device to signal, by using a detection signal, if the hand is moved toward the operating element in order to actuate the operating element and/or if the operating element is actuated. If the detection device generates the detection signal, the air flow emerging from the at least one air outlet opening is reduced and/or diverted to a side of the vehicle or downward, for example, by the air-conditioning device. The reduction in the air flow may cause, on the one hand, attenuation of the air flow and, on the other hand, also complete interruption of the air flow. In other words, the amount of air conveyed through the at least one air outlet opening per unit time is reduced by reducing the air flow. In order to reduce the air flow, the speed of a fan, for example, which drives or conveys the air flow can be reduced or the fan can be switched off during the operating process. The diversion can be achieved, for example, by using motor-pivotable fins in the at least one air outlet opening. 
         [0012]    The method has the advantage that it is possible to operate the operating element by a hand without incident flow and new design possibilities are nevertheless enabled in the interior of the motor vehicle by arranging the operating element above an air outlet opening. 
         [0013]    The detection device may be a signal-processing computing device, for example a control device or a microcontroller, and a suitable sensor system connected upstream. In this case, the sensor system detects or senses when the hand approaches the operating element and/or the operating process itself. According to one development of the method, the detection device generates the detection signal on the basis of an operating signal from the operating element itself. If the operating element is a pushbutton, for example, its switching signal can be used not only to control the associated device of the motor vehicle but also as a detection signal for the air-conditioning device when actuating the pushbutton. In the case of a touchscreen, the touch sensor system, that is to say the sensor matrix described, can accordingly be used to generate the operating signal. The use of the operating signal from the operating element itself has the advantage that it is possible to recognize in a very robust manner, without an additional sensor system, when there is a need to reduce and/or divert the air flow. 
         [0014]    Another development of the method provides for the detection device to generate the detection signal on the basis of an additional sensor system different from the operating element. This is preferably a sensor system which is also provided for other functionalities of the motor vehicle, with the result that no additional sensor system likewise has to be installed. One development provides for the additional sensor system to include at least one of the following sensors: a video camera, an infrared camera, a time-of-flight camera (ToF camera), a capacitive sensor, and the like. These sensors have the advantage that it is already possible to contactlessly detect when the hand approaches the operating element. The cameras described may be provided, for example, by a gesture recognition device of the motor vehicle or a driver fatigue detection system. Their signals may also be supplied to a control device of the air-conditioning device in order to control the air flow on the basis of the camera signals. 
         [0015]    An advantageous development results if the detection device generates the detection signal on the basis of a recognition signal from a gesture recognition device. This advantageously makes it possible to additionally check whether the hand has a predetermined posture and/or an extrapolated movement trajectory of the hand is aligned with the operating element. Monitoring the hand posture and detecting a particular hand shape, for example an index finger extended in order to touch the operating element, makes it possible to detect, in a particularly reliable manner, whether the user actually has a desire for operation, that is to say actually plans to operate the operating element. The “Kinect” function library from Microsoft can be used, for example, to detect a hand shape. Extrapolating a movement trajectory results in the advantage that it is already possible to detect at a very early stage whether the user is actually aiming for the operating element with his hand. As a result, the air flow can already be reduced and/or diverted when the hand passes an air outlet opening from below. 
         [0016]    In order to obtain as few false recognitions as possible, one development of the method provides for the detection device to generate the detection signal on the basis of sensor signals from a plurality of sensors. In this case, a probability value is preferably determined for each sensor signal indicating that operation of the operating element is imminent. As a result, it is also possible to use sensor signals which, although constituting an indication of imminent operation of the operating element, are not unambiguous. The appropriate probability value can be determined in simple experiments by observing test subjects. The probability value therefore indicates that operation of the operating element is imminent. A total probability is then formed from the probability values of all evaluated sensor signals and the detection signal is generated only if the total probability value satisfies a predetermined triggering criterion, that is to say the total probability is, for example, above a predetermined threshold value, for example 70% or 80%. 
         [0017]    However, reducing and/or diverting the air flow is not always useful. For example, a thumb wheel or another adjusting apparatus of the air-conditioning apparatus itself, which is provided for the purpose of adjusting the air flow, may be arranged at an air outlet opening itself. In this case, mechanically adjustable diverting blades or the thumb wheel mentioned may be present, for example, for the purpose of changing the cross section of the air outlet opening through which there is a flow. If the user now reaches for this adjusting apparatus in order to adjust the air flow, it does not make any sense to reduce the air flow or to guide it away from the hand. It is then no longer possible for the user to carry out an adjustment by using the adjusting apparatus. Therefore, one development of the method provides that, while an adjusting apparatus of the air-conditioning device, which is provided for the purpose of adjusting the air flow, is operated, the air flow is adjusted only on the basis of the operation of the adjusting apparatus and simply independently of the position of the hand and operation of the operating element. In other words, the air flow is therefore adjusted independently of a position of the hand and operation of the operating element while adjusting the air flow by using the adjusting apparatus. This results in the advantage that, during the adjustment, the user senses exactly that air flow which is also still generated by the air-conditioning device after the hand has been removed. In order to solve this problem of distinguishing between imminent operation of the operating element for a device of the motor vehicle, on the one hand, and the imminent operation of the adjusting apparatus of the air-conditioning device, on the other hand, in as simple a manner as possible, one development of the method provides for the detection signal to be generated only if the hand is above a particular minimum height, wherein the air outlet opening is below the minimum height. In other words, the user must therefore initially lift his hand above the minimum height before the detection signal is used to signal that actuation of the operating element is imminent. This height-dependent triggering can be implemented in a particularly reliable manner using the ToF camera already described. Capacitive sensors on or in the operating element or between the operating element and the at least one air outlet opening also make it possible to reliably detect a hand raised above the minimum height. 
         [0018]    Another development of the method provides for the operating element to be a touchscreen, and for the air-conditioning device to not generally change the air flow in this case everywhere in the region of the at least one air outlet opening. The air-conditioning device changes the air flow on the basis of a location at which a finger of the hand touches the touchscreen only to the extent that a portion of the air flow flowing under the touch location is reduced and a remaining portion of the air flow remains unchanged. This makes it possible to achieve, for example, the situation in which only that portion of the air flow in which a hand is actually situated is reduced, while the remaining portion of the air flow which can flow past the hand without obstruction is also maintained without change. 
         [0019]    A motor vehicle can be used to carry out the method according to the method described herein. In this case, the motor vehicle is preferably in the form of an automobile, in particular a passenger automobile, wherein the motor vehicle has an operating element designed to operate at least one device and an air-conditioning device. An air outlet opening for blowing air into a vehicle interior of the motor vehicle is arranged on a lower side of the operating element in the described manner. The motor vehicle has the described detection device for monitoring an operating desire of the user and for generating a detection signal. The motor vehicle may include an air-conditioning device designed to reduce and/or divert the air flow on the basis of the detection signal. 
         [0020]    The described operating element of the motor vehicle may be a touchscreen which can be arranged, in particular, on a dashboard of the motor vehicle. 
         [0021]    Additional developments of the motor vehicle may include features which have already been described in connection with the developments of the method. For this reason, the corresponding developments of the motor vehicle are not described again here. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0022]    These and other aspects and advantages will become more apparent and more readily appreciated from the following description of the exemplary embodiments, taken in conjunction with the accompanying drawing of which: 
           [0023]    An exemplary embodiment in the single FIGURE shows a schematic illustration of an embodiment of the motor vehicle. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0024]    In the exemplary embodiment, the described components of the embodiment are each individual features which can be considered independently of one another and each also develop the disclosure independently of one another and therefore can also be considered individually or in a combination other than the combination shown. Furthermore, the described embodiment can also be supplemented with further features which have already been described. 
         [0025]    The FIGURE illustrates a vehicle interior  12  of a motor vehicle  10 . A dashboard  14 , a steering wheel  16  and a windshield  18  are shown. The dashboard  14  may have, for example in a manner arranged in the center of the vehicle, an operating element  20  which may be a touchscreen, for example. The operating element  20  can be used to operate an infotainment system I of the motor vehicle, for example. Air outlet openings  24 ,  26  through which an air-conditioning system  28  respectively blows or conveys an air flow  30 ,  32  into the vehicle interior  12  may be arranged on a lower side  22  of the operating element  20 . A distance between the lower side  22  and the air outlet openings  24 ,  26  may be less than 15 cm, for example, in particular less than 10 cm, very particularly less than 5 cm. 
         [0026]    An adjusting apparatus  34 ,  36 , for example with a thumb wheel, can be respectively provided laterally beside the air outlet openings  24 ,  26  and can be used by an operator to manually regulate the respective air flow  30 ,  32  in a known manner. The air outlets  24 ,  26 , the air-conditioning system  28  and the adjusting apparatuses  34 ,  36  together form an air-conditioning device. 
         [0027]    In the example shown, a driver would like to carry out an operating action using his hand  38  on the touchscreen  20  in order to operate the infotainment system I, for example. For this purpose, the driver would like to use his extended index finger  40  to tap, for example, on a graphical object  42 , which may be an operating panel (button) or a menu entry for example, on the touchscreen  20 . For this purpose, the driver moves his hand  38  along a movement trajectory  44 , for example from a position of rest  46 , in the direction of the touchscreen  20 . In this case, the driver must move his hand  38  through one or both of the air flows  30 ,  32 . The driver holds his hand  38  or his forearm  48  in the region of the air flows  30 ,  32  even while operating the touchscreen  20 , that is to say while tapping on the object  42 , for example, and further graphical objects displayed on the touchscreen  20 . 
         [0028]    In the motor vehicle  10 , however, it is ensured that the hand  38  and the arm  48  are not subjected to a hot or cold air flow  30 ,  32  in a manner perceived as unpleasant during the operating process. For this purpose, a detection device  50  is provided in the motor vehicle  10 , which detection device may comprise, for example, a program module of the infotainment system I or of an intracentral computing device or of a control device. The detection device  50  senses when the hand  38  approaches the touchscreen and signals a detected approach and/or operation of the touchscreen  20  which has already been carried out to the air-conditioning system  28  by using a detection signal D. 
         [0029]    The air-conditioning system  28  can then reduce the speed of a fan (not illustrated) of the air-conditioning system  28  or can switch off the fan, for example, on the basis of the detection signal D. In this case, the fan is that device which drives at least one of the air flows  30 ,  32 . Additionally or alternatively, provision may also be made for fins  52 ,  54  arranged in the air outlet openings  24 ,  26  to be motor-adjusted on the basis of the detection signal D, with the result that the air flows  30  and/or  32  are diverted and, as a result, are guided past the hand  38  and the arm  48 . Solely diverting the air flows  30 ,  32  results in the additional advantage that the amount of air conveyed into the vehicle interior  12  overall per unit time remains unchanged and the air-conditioning performance is not impaired thereby. 
         [0030]    In order to detect when the hand  38  approaches the touchscreen  20 , a signal S from a camera  56  of the motor vehicle  10  can be received by the detection device  50 , for example, and the hand  38  can be detected in the vehicle interior  12  using the camera signal. Provision may be made, for example, for the movement trajectory  44  of a geometrical center of gravity of the hand  38 , for example, to be detected using the camera signal S and for the movement trajectory  44  to be extended by using an extrapolation  58  and for a check to be carried out thereby in order to determine whether the hand  38  is moving toward the operating element  20 . This is then recognized by the detection device  50  as an operating intention of the driver and the detection signal D is generated. 
         [0031]    Provision may also be made for an operating signal from the operating element  20  itself to be evaluated by the detection device  50  as a further sensor signal S and therefore for the detection signal D to be generated during operation of the operating element  20 , that is to say while the object  42  is being pressed, for example. 
         [0032]    The camera  56  may also be a ToF camera, for example a PMD camera (PMD—Photonic Mixing Device). This also makes it possible to evaluate, for example, an item of height information relating to the position of the hand  38  in the vehicle interior  12 . Provision may be made for the detection signal D not to be generated as long as the hand  38  is below a predetermined minimum height  60  below the lower side  22 . As a result, it is then possible for the driver to operate the adjusting apparatuses  34 ,  36  without the air flows  30 ,  32  already being changed on account of an unintentionally generated detection signal as a result of the hand  38  approaching the adjusting apparatuses  34 ,  36 . 
         [0033]    In the example shown, the graphical object is situated on a right-hand side above the air outlet opening  26 . Provision may be made for the detection device  50  to signal, by using the signal D, that only the air flow  32  below the graphical object  42  is intended to be reduced and/or diverted. In other words, in this embodiment, the left-hand air flow  30  remains unchanged, while the driver, with his hand  38  on the touchscreen, uses his finger  40  to tap on the graphical object  42  on the right-hand half of the touchscreen  20 . In this case too, the driver then does not sense any unpleasant air flow since the air flow  30  is not directed at his hand  38  or his arm  48 . 
         [0034]    Particularly early detection of the operating intention is also possible if the detection device  50  uses the position of the hand  38  to check whether the driver intends to operate the touchscreen  20 . For this purpose, it is possible to check, for example, whether the index finger  40  has been extended for operation and to then generate the detection signal D only for this case. For this purpose, the motor vehicle  10  may have a gesture recognition device G which checks whether the hand has a predetermined gesture or position. If it is detected that the hand  38  has the position, this is signaled to the detection device  50  by the gesture recognition device G by using a recognition signal E. The gesture recognition device G may be, for example, a program module of a central computing device, of the infotainment system I or of the control device of the motor vehicle  10 . 
         [0035]    Overall, the example therefore shows how air-conditioning control can be achieved in a motor vehicle on the basis of the operation of a touchscreen in order to avoid the hand being exposed to a flow in a manner perceived as unpleasant during operation of the touchscreen. This makes it possible to also arrange the touchscreen above air outlet openings of the air-conditioning device. 
         [0036]    A description has been provided with particular reference to embodiments thereof and examples, but it will be understood that variations and modifications may be effected within the spirit and scope of the claims which may include the phrase “at least one of A, B and C” as an alternative expression that means one or more of A, B and C may be used, contrary to the holding in  Superguide  v.  DIRECTV,  358 F3d 870, 69 USPQ2d 1865 (Fed. Cir. 2004).