Method and device for detecting the state of an air filter of an air conditioning system

Abstract

A method and a device detects the state of an air filter in an air conditioning system for the interior of a motor vehicle. Condensed water created at the evaporator is discharged and fed to a sensor, which determines a parameter of the condensed water, and which, from a change or a certain value of the measured parameter, draws a conclusion regarding a change of the state of the air filter.

1 . A method for detecting the state of an air filter in an air conditioning system for the interior of a motor vehicle, comprising the following steps: 
 feeding condensed water created at an evaporator of the air conditioning system to a sensor;    detecting with the sensor at least one physical characteristic of the water represented by a value; and    deriving a statement regarding the state of the air filter from the value detected by the sensor.    
     
     
         2 . The method according to  claim 1 , wherein the sensor detects a change of an electric field.  
     
     
         3 . The method according to  claim 1 , wherein the sensor detects a changing oscillating behavior of a tuning fork.  
     
     
         4 . The method according to  claim 1 , wherein the detected values are checked regarding a temporal change of the detected value.  
     
     
         5 . The method according to  claim 1 , wherein the detected value is compared with a reference value.  
     
     
         6 . A device for detecting the state of an air filter in an air conditioning system for the interior of a motor vehicle, comprising: 
 a condensed water discharge; and    a sensor disposed in the condensed water discharge.    
     
     
         7 . The device according to  claim 6 , wherein the sensor detects physical characteristics of the water.  
     
     
         8 . The sensor according to  claim 6 , wherein the sensor has a capacity.  
     
     
         9 . The device according to  claim 6 , wherein the sensor has an interdigital resistor.  
     
     
         10 . The device according to  claim 6 , wherein the sensor has a tuning fork.  
     
     
         11 . The device according to  claim 6 , wherein the sensor is disposed in a container that is connected to the condensed water discharge.  
     
     
         12 . The device according to  claim 11 , wherein the sensor is a level sensor.  
     
     
         13 . An air conditioning system for a motor vehicle comprising: 
 an evaporator;    a condensed water discharge disposed in an area of the evaporator; and    a sensor disposed in the condensed water discharge.    
     
     
         14 . A motor vehicle with an air conditioning system comprising: 
 an evaporator;    an air filter;    a condensed water discharge disposed in the area of the evaporator; and    a sensor disposed in the condensed water discharge.