Tire tread thickness gauging apparatus

Claim 1

A TIRE TREAD THICKNESS VARIATION GAUGE COMPRISING, IN COMBINATION, ROTATABLE TIRE SUPPORTING AND DRIVING MEANS ADAPTED TO CONTACT A TIRE AT THE INTERIOR TREAD AREA THEREOF AND TO POSITION SAID TIRE HORIZONTALLY AND VERTICALLY, SAID TIRE SUPPORTING AND DRIVING MEANS COMPRISING A PAIR OF DRIVEN HEMISPHERICAL MEMBERS, MEANS TO PULL SAID TIRE FIRMLY DOWN AGAINST SAID SUPPORT MEANS, RECIPROCATIVE MEANS MOVABLE INTO CONTACT WITH OUTER TREAD AREA OF THE TIRE, MEANS TO ROTATE SAID TIRE SUPPORTING MEANS AND SAID TIRE, MEANS TO MOVE SAID RECIPROCATIVE MEANS INTO CONTACT WITH THE TIRE TREAD, A FIRST DIFFERENTIAL TRANSFORMER MEANS ASSOCIATED WITH SAID RECIPROCATIVE MEANS TO DETERMINE THE MAGNITUDE OF MOVEMENT OF SAID RECIPROCATIVE MEANS DURING THE ROTATION OF SAID TIRE AND ADAPTED TO PRODUCE A SIGNAL PROPORTIONAL TO THE MOVEMENT OF SAID RECIPROCATIVE MEANS AND A SERVO MEANS RESPONSIVE TO SAID SIGNAL AND INCLUDING A SECOND DIFFERENTIAL TRANSFORMER MEANS ADAPTED TO DERIVE A SIGNAL THROUGH THE REACTION OF SAID SERVO SUBSTANTIALLY EQUAL AND OPPOSITE TO THE SIGNAL OF SAID FIRST DIFFERENTIAL TRANSFORMER MEANS WHEREBY A NULL BALANCE CONDITION OS PRODUCED BY OPPOSING SAID SIGNALS, MEANS TO COMPARE THE MAXIMUM MOVEMENT OF SAID RECIPROCATING MEANS WITH A STANDARD AS DETERMINED BY METER RELAY MEANS AND TO CAUSE REJECTION OF SAID TIRE IF SAID MOVEMENT EXCEEDS SAID STANDARD, AND MEANS TO EJECT A TIRE FROM SAID SUPPORT AND DRIVE MEANS.