Hvac system of an automotive vehicle and method of operating the same

Abstract

A climate control system for the interior cabin of an automotive vehicle. The climate control system includes a mode selection device configured for selecting a defrost mode. When the system is in the defrost mode, a controller receives a signal from a humidity sensor indicative of the measured humidity level in the vicinity of the window. The controller compares this measured humidity level with a threshold humidity level and, if the humidity is below the threshold humidity level, the controller stops operation of a compressor being used to dehumidify the air being provided to defrost the window, thereby minimizing possible fogging of the window and increasing the efficiency of the vehicle.

I/we claim: 
     
         1 . A climate control system for the interior cabin of an automotive vehicle, the climate control system comprising:
 a mode selection device configured for selecting between a defrost mode and at least one non-defrost mode;   a compressor and condenser configured to dehumidify air being provided to an interior cabin of the automotive vehicle;   a humidity sensor located adjacent to a window of the automotive vehicle;   a controller coupled to the mode input device, the compressor and condenser, and to the humidity sensor;   a blower configured to move air over the condenser in providing air to the cabin of the automotive vehicle; and   wherein, when the mode selection device is in the defrost mode, the controller being configured to receive a humidity signal from the humidity sensor indicative of the humidity in the vicinity of the window and being configured to operate a compressor if the humidity is above a threshold value and to not operate the compressor if the humidity is below the threshold value.   
     
     
         2 . The climate control system of  claim 1 , wherein the window is a windshield of the automotive vehicle. 
     
     
         3 . The climate control system of  claim 1 , wherein the window is a side window of the automotive vehicle. 
     
     
         4 . The climate control system of  claim 1 , further comprising two humidity sensors and wherein the controller is configured to operate the compressor if the humidity signal from at least one of the two humidity sensors is greater than the threshold value and is configured to not operate the compressor if the humidity signals from all of the humidity sensors are below the threshold value. 
     
     
         5 . The climate control system of  claim 1 , further comprising an air vent located adjacent to the window and coupled to direct air from the blower onto the window. 
     
     
         6 . The climate control system of  claim 5 , wherein the humidity sensor is spaced apart from the vent. 
     
     
         7 . The climate control system of  claim 1  wherein the humidity sensor is located adjacent to a lower portion of the window. 
     
     
         8 . A method of operating a climate control system of an automotive vehicle, the method comprising the steps of:
 measuring the humidity of air in a vicinity of a window of the automotive vehicle;   determining if the climate control system is in a defrost mode;   providing a flow of air specifically directed toward the window when the climate control system is in the defrost mode;   measuring the humidity of air in the vicinity of the window;   comparing the measured humidity with a threshold humidity value;   determining if a compressor coupled to a condenser provided as part of an air conditioning subsystem is operating; and   if the compressor is operating, turning OFF the compressor when the measured humidity is less than the threshold humidity value.   
     
     
         9 . The method of  claim 8 , further comprising the step of measuring the humidity of air in two locations within the vicinity of the window. 
     
     
         10 . The method of  claim 9 , wherein if the measured humidity at one of the two locations is above the threshold humidity value, the compressor is not turned OFF. 
     
     
         11 . The method of  claim 9 , wherein if the measured humidity at both of the two locations is below the threshold humidity value, the compressor is turned OFF. 
     
     
         12 . The method of  claim 8 , further comprising the step of heating the flow of air. 
     
     
         13 . A climate control system for the interior cabin of an automotive vehicle, the climate control system comprising:
 a defrost mode selection device provided as part of a user interface and being selectable to enter a defrost operational mode of the climate control system;   a compressor and a condenser configured to dehumidify a flow of air being provided to an interior cabin of the automotive vehicle, the condenser being located within the flow of air;   at least one humidity sensor located adjacent to a window of the automotive vehicle and configured to provide a measured humidity signal indicative of a measured humidity level;   a controller coupled to the defrost mode input device, the at least one humidity sensor, and the compressor and condenser;   a blower configured to move air over the condenser when providing the flow of air to the cabin of the automotive vehicle; and   wherein, when the defrost mode selection device is selected, the controller being configured to receive the measured humidity signal from the at least one humidity sensor and being configured compare the measured humidity level to a threshold humidity level, wherein the controller is configured to stop operation of the compressor if the measured humidity level is less than the threshold humidity level.   
     
     
         14 . The climate control system of  claim 13 , wherein the window is one of a windshield and a side window of the automotive vehicle. 
     
     
         15 . The climate control system of  claim 13 , wherein the controller is configured to continue operation of the compressor if the measured humidity level is greater than the threshold humidity level. 
     
     
         16 . The climate control system of  claim 13 , further comprising a plurality of humidity sensors, the controller being configured to stop operation of the compressor if the measured humidity levels from all of the humidity sensors are less than the threshold humidity level. 
     
     
         17 . The climate control system of  claim 13 , further comprising a plurality of humidity sensors, the controller being configured to not stop operation of the compressor if the measured humidity levels from all of the humidity sensors are not less than the threshold humidity level. 
     
     
         18 . The climate control system of  claim 17 , wherein the plurality of humidity sensors is spaced along a windshield of the automotive vehicle.