Methods and apparatus for evaluating insulating glass units

Abstract

An apparatus and method for measuring the gas fill concentration of insulating glass units is disclosed. One apparatus includes a gas fill concentration measuring device coupled to a production line for manufacturing insulating glass units. One method of the invention involves measuring the gas fill concentration of insulating glass units after they have been filled with gas and sealed.

1 . A system for producing insulating glass units in a production line environment, the system comprising: 
 a conveyer for transporting components that form the insulating glass units as well as the insulating glass units themselves to stations located along the production line;    a gas fill concentration measuring device located at a station of the production line wherein the device measures the gas fill concentration of an insulating glass unit delivered to that station and generates a signal based on a gas fill concentration measurement; and    a computer configured to receive the signal generated by the device and to decide whether to accept or reject the insulating glass unit based upon the signal.    
   
   
       2 . The system of  claim 1 , further comprising an extendable member located at the station with the device wherein the extendable member contacts and secures the insulating glass unit while the gas fill concentration is measured.  
   
   
       3 . The system of  claim 1 , wherein the gas fill concentration sensor is coupled to the extendable member.  
   
   
       4 . The system of  claim 1 , wherein the extendable member is movable in at least the X or Y axis relative to the insulating glass unit.  
   
   
       5 . The system of  claim 1 , wherein the gas fill concentration sensor operates during a single stop period.  
   
   
       6 . The system of  claim 5 , wherein the stop period is in the range of 10-20 seconds.  
   
   
       7 . The system of  claim 1 , wherein the device, comprises: 
 a means for emitting a light emission from within the interpane space of the insulating glass unit; and    a photosensor for sensing light from the light emission that has passed through at least a portion of the insulating glass unit.    
   
   
       8 . The system of  claim 7 , wherein the means for emitting a light emission from within the interpane space of the insulating glass unit comprises a field generator for exciting a gas disposed in the interpane space to form a plasma.  
   
   
       9 . The apparatus of  claim 8 , wherein the generator is configured to generate an oscillating magnetic field proximate an outer surface of the insulating glass unit.  
   
   
       10 . The system of  claim 7 , wherein the signal is based on light sensed by the photosensor from the light emission.  
   
   
       11 . The system of  claim 10 , wherein the computer is configured to: 
 compare the signal with an acceptable range; and    generate a reject signal if the signal is outside the acceptable range.    
   
   
       12 . The system of  claim 10 , wherein the computer is configured to: 
 compare the signal with an acceptable range; and    generate an accept signal if the signal is within the acceptable range.    
   
   
       13 . The system of  claim 10 , wherein the computer is configured to correct the signal to compensate for a color change occurring in light from the light emission as that light passes through a single pane of the insulating glass unit.  
   
   
       14 . A method for measuring gas fill concentration of insulating glass units during manufacture thereof, the method comprising the steps of: 
 conveying a gas-filled insulating glass unit to a gas fill concentration measuring station to obtain a gas fill measurement;    measuring the gas fill concentration of the insulating glass unit at the gas fill concentration measuring station, determining whether the gas fill concentration measurement is within an acceptable range; and    accepting or rejecting the insulating glass unit.    
   
   
       15 . The method of  claim 14 , further comprising the step of transmitting gas fill concentration data to a database for storage.  
   
   
       16 . The method of  claim 14 , further comprising the steps of: 
 coupling two panes of glass together to create an interpane space therebetween;    filling the interpane space with insulating gas to produce a partially formed insulating glass unit;    measuring gas fill concentration of the partially formed insulating glass unit at a station on a production line,    determining whether the gas fill concentration is within an acceptable range;    accepting or rejecting the insulating glass unit.    
   
   
       17 . The method of  claim 16 , further comprising transmitting gas fill concentration data to a data base for storage.  
   
   
       18 . A method for evaluating an insulating glass unit comprising the steps of: 
 emitting a light emission from a light source disposed within an interpane space of the insulating glass unit;    sensing light from the light emission that has passed through at least a portion of the insulating glass unit;    generating a signal based on the light sensed from the light emission;    providing the signal to a computer configured to determine whether light sensed from the light emission is within acceptable ranges; and    accepting or rejecting the insulating glass unit.    
   
   
       19 . The method of  claim 18 , wherein the step of sensing light from the light emission that has passed through at least a portion of the insulating glass unit comprises the step of sensing light from the light emission that has passed through a single pane of the insulating glass unit.  
   
   
       20 . The method of  claim 18 , wherein the light source comprises a plasma.  
   
   
       21 . The method of  claim 18 , wherein the step of emitting a light emission from the light source comprises the step of exciting a gas disposed in the interpane space to form a plasma.  
   
   
       22 . The method of  claim 21 , wherein the gas disposed in the interpane space comprises argon.  
   
   
       23 . The method of  claim 21 , wherein the step of exciting the gas disposed in the interpane space comprises the step of generating an oscillating magnetic field proximate an outer surface of the insulating glass unit.  
   
   
       24 . The method of  claim 18 , further including the step of deciding whether to accept the insulating glass unit based upon the signal.  
   
   
       25 . The method of  claim 18 , further including the steps of: 
 comparing the signal with an acceptable range; and    generating a reject signal if the signal is outside the acceptable range.    
   
   
       26 . The method of  claim 18 , further including the steps of: 
 comparing the signal with a second acceptable range; and    generating an accept signal if the first signal is within the first acceptable range.    
   
   
       27 . The method of  claim 18 , further including the step of correcting the signal to compensate for a color change occurring in light from the light emission as the light passes through a single pane of the insulating glass unit.  
   
   
       28 . The method of  claim 27 , wherein the step of correcting the signal comprises the step of calculating a color change that occurs in light from the first light emission as it passes through at least a portion of the insulating glass unit.