Ex parte QIN - Page 18




          Appeal No. 1997-1111                                      Page 18           
          Application No. 08/105,899                                                  


          (brief, page 17) that Hägglund does not suggest using a signal              
          generator with a fuzzy logic controller, and that (reply                    
          brief, page 5) the fact that both Ueda and Hägglund mention                 
          the Ziegler-Nichols method does not suggest the claimed steps               
          of appellant’s method.                                                      
               We find that Hägglund discloses the use of a non-linear                
          circuit to provide a controlled induced oscillation for tuning              
          a PID.  However, in Hägglund (col. 3, lines 5-11) the system                
          is brought into self oscillation by disconnecting the                       
          integrating and derivative units I and D of the regulator, and              
          increasing the amplification of the proportional control unit               
          P, by manually moving adjusting means 9.  Hägglund further                  
          discloses (col. 4, lines 39-47) completely disconnecting the                
          PID controller.  In addition, Hägglund discloses (col. 4,                   
          lines 64 and 65) that “[a]lso the I- and D-units can be                     
          connected individually or in combination-also with the P-                   
          unit.”  We are in general agreement with the examiner that PID              
          controllers and fuzzy controllers are both well known in the                
          art and that the Ziegler-Nichols method of tuning is used in                
          both PID and fuzzy controllers.  However, we find no                        
          suggestion to combine the teachings of Hägglund with Ueda for               







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