Thickness measuring method and apparatus employing microwaves

Claim 1

A MEASURING DEVICE INCLUDING, IN COMBINATION, FIRST MEANS FOR TRANSMITTING A SIGNAL TOWARDS ONE SIDE OF A REFLECTING SURFACE AND FOR RECEIVING THE SIGNAL REFLECTED THEREFROM, SECOND MEANS FOR TRANSMITTING A SIGNAL TOWARDS THE OPPOSITE SIDE OF THE REFLECTING SURFACE AND FOR RECEIVING THE SIGNAL REFLECTED FROM SAID OPPOSITE SIDE, FIRST SEPARATION MEANS COUPLED TO SAID FIRST MEANS FOR SEPARATING A SIGNAL TO BE TRANSMITTED FROM THE SIGNAL REFLECTED FROM SAID ONE SIDE AND PROVIDING AN OUTPUT SIGNAL CORRESPONDING TO THE REFLECTED SIGNAL, SECOND SEPARATION MEANS COUPLED TO SAID SECOND MEANS FOR SEPARATING A SIGNAL TO BE TRANSMITTED FROM THE SIGNAL REFLECTED FROM SAID OPPOSITE SIDE AND PROVIDING AN OUTPUT SIGNAL CORRESPONDING TO THE REFLECTED SIGNAL, A SOURCE OF SIGNALS TO BE TRANSMITTED COUPLED TO THE FIRST AND SECOND SEPARATION MEANS, FIRST DETECTOR MEANS HAVING A LINEAR REGION IN ITS TRANSFER CHARACTERISTICS COUPLED TO BE RESPONSIVE TO THE OUTPUT SIGNAL FROM SAID FIRST SEPARATION MEANS OVER THE SAID LINEAR REGION OF ITS TRANSFER CHARACTERISTICS AND PROVIDING AN OUTPUT SIGNAL PROPORTIONAL TO THE DISTANCE BETWEEN SAID FIRST MEANS AND THE ONE SIDE OF THE REFLECTING SURFACE OF THE MATERIAL TO BE MEASURED, SECOND DETECTOR MEANS HAVING A LINEAR REGION IN ITS TRANSFER CHARACTERISTICS COUPLED TO BE RESPONSIVE TO THE OUTPUT SIGNAL FROM SAID SECOND SEPARATION MEANS OVER THE SAID LINEAR REGION OF ITS TRANSFER CHARACTERISTICS AND PROVIDING AN OUTPUT SIGNAL PROPORTIONAL TO THE DISTANCE BETWEEN SAID SECOND MEANS AND SAID OPPOSITE SIDE OF THE REFLECTING SURFACE, AND MEANS CONNECTED TO BE RESPONSIVE TO THE OUTPUT SIGNALS FROM THE FIRST AND SECOND DETECTOR MEANS FOR COMBINING THE APPLIED SIGNALS.

Claim 3

A METHOD OF CONTINUOUSLY MEASURING THE THICKNESS OF A CONTINUOUSLY MOVING MATERIAL INDEPENDENT OF TRANSLATORY MOTION AND POSITION OF THE MATERIAL BEING MEASURED, INCLUDING THE STEPS OF ADVANCING A MATERIAL TO BE MEASURED, CONTINUOUSLY REFLECTING MICROWAVE SIGNALS FROM OPPOSITE SIDES OF THE MATERIAL TO BE MEASURED, DETECTING THE REFLECTED SIGNALS AND PROVIDING AN ELECTRICAL OUTPUT INDICATION REPRESENTATIVE OF THE DISTANCE TRAVELED BY THE REFLECTED SIGNALS TO THE ADVANCING MATERIALS, AND COMBINING THE ELECTRICAL OUTPUT INDICATIONS AND PROVIDING A COMPOSITE SIGNAL PROPORTIONAL TO THE TOTAL DISTANCE TRAVELED BY THE REFLECTING SIGNALS.

Claim 4

A METHOD OF CONTINUOUSLY MEASURING THE THICKNESS OF A CONTINUOUSLY MOVING MATERIAL INDEPENDENT OF TRANSLATORY MOTION AND POSITION OF THE MATERIAL BEING MEASURED, INCLUDING THE STEPS OF ADVANCING A MATERIAL TO BE MEASURED, CONTINUOUSLY REFLECTING MICROWAVE SIGNALS FROM OPPOSITE SIDES OF THE MATERIAL TO BE MEASURED, DETECTING THE REFLECTED SIGNALS AND PROVIDING AN ELECTRICAL OUTPUT INDICATION REPRESENTATIVE OF THE DISTANCE TRAVELED BY THE REFLECTED SIGNALS TO THE ADVANCING MATERIALS, AND COMBINING THE ELECTRICAL OUTPUT INDICATIONS AND PROVIDING A COMPOSITE SIGNAL PROPORTIONAL TO THE TOTAL DISTANCE TRAVELED BY THE REFLECTING SIGNALS.