System for controlling a structure according to a predetermined program of operation

Claim 1

APPARATUS FOR CONTROLLING IN A SUBJECT STRUCTURE A MEASURABLE QAUALITY IN A PREDETERMINED MANNER, COMPRISING A DEVICE FOR PRODUCING AND FREQUENCY MODULATING AN ELECTRICAL SIGNAL HAVING A RANGE OF FREQUENCIES REPRESENTATIVE OF THE RANGE OF VARIATION OF SAID QUALITY, MEANS COUPLED TO SAID DEVICE FOR RECORDING SAID SIGNAL TO PROVIDE A REPRODUCING RECORD OF SAID SIGNAL, MEANS FOR REPRODUCING SAID SIGNAL FROM SAID RECORD, TRANSDUCER MEANS ADAPTED TO SENSE THE PRESENCE AND EXTENT OF SAID QUALITY IN SAID STRUCTURE AND FOR PRODUCING A FREQUENCY MODULATED CONDITION INDICATING SIGNAL IN ACCORDANCE THEREWITH, SAID TRANSDUCER MEANS AND SAID DEVICE BEING ADJUSTED TO THE SAME FREQUENCY RANGE WITH RESPECT TO EACH OTHER, FREQUENCY COMPARATOR MEANS COUPLED WITH SAID TRANSDUCER MEANS AND SAID REPRODUCING MEANS FOR COMPARING THE FREQUENCY OF SAID REPRODUCED SIGNAL WITH THAT OF SAID CONDITION INDICATING SIGNAL, SAID COMPARATOR MENS BENG OPERBALE TO SAMPLE SAD REPRODUCED SIGNAL AND SAID CONDITION INDICATING SIGNAL ALTERNATELY AT A PREDETERMINED FREQUENCY AND MEANS COUPLED WITH SAID COMPARATOR MEANS AND RESPONSIVE TO THE DIERENCE BETWEEN SAID COMPARED SIGNALS FOR CONTROLLING SAID SUBJECT STRUCTURE TO ELIMINATE SAID DIFFERENCE.