Condition controlling apparatus, particularly for controlling temperatures

Claim 1

IN A SYSTEM FOR SUPPLYING ENERGY FROM A SOURCE TO AN ENERGY UTILIZATION DEVICE WHICH CHANGES A VARIABLE CONDITION, THE UTILIZATION DEVICE BEING CHARACTERIZED BY A DECREASE IN ITS ENERGY-CONSUMING ABILITY AS THE VALUE OF SAID CONDITION INCREASES, THE COMBINATION COMPRISING, MEANS FOR CREATING A SIGNAL WHICH VARIES IN ACCORDANCE WITH THE INSTANTANEOUS VALUE OF SAID CONDITION, CONTROL MEANS INTERPOSED BETWEEN SAID SOURCE AND SAID UTILIZATION DEVICE FOR PRESENTING A VARIABLE OPPOSITION TO THE TRANSFER OF ENERGY FROM THE FORMER TO THE LATTER, AND MEANS RESPONSIVE TO SAID SIGNAL FOR CAUSING THE OPPOSITION PRESENTED BY SAID CONTROL MEANS TO VARY INVERSELY WITH CHANGES IN THE VALUE OF THE CONTROLLED CONDITION, SO THAT THE RATE OF ENERGY TRANSFER FROM THE SOURCE TO THE DEVICE REMAINS SUBSTANTIALLY CONSTANT AS THE VALUES OF THE CONTROLLED CONDITION AND THE ENERGY-CONSUMING ABILITY OF THE UTILIZATION DEVICE CHANGE.