Angle of rotation measuring apparatus

Claim 1

APPARATUS COMPRISING: A DRUM ROTATABLE ABOUT AN AXIS AND HAVING A SIGNAL TRACK THEREON; FIRST AND SECOND SIGNAL RESPONSIVE MEANS MOUNTED IN A FIXED RELATIONSHIP TO SAID SIGNAL TRACK WHEREBY SAID FIRST SIGNAL RESPONSIVE MEANS DELIVERS A SIGNAL WHEN A SPECIFIC PORTION OF SAID TRACK IS IN PROXIMITY THERETO AND SAID SECOND SIGNAL RESPONSIVE MEANS DELIVERS A SIGNAL BWHEN ANY OF A PLURALITY OF PORTIONS OF SAID TRACK ARE IN PROXIMITY THERETO; THIRD AND FOURTH SIGNAL RESPONSIVE MEANS ROTATABLY MOUNTED AROUND SAID AXIS IN PROXIMITY TO SAID SIGNAL TRACK AND MOVABLE WITH RESPECT TO SAID FIRST AND SECOND SIGNAL RESPONSIVE MEANS WHEREBY SAID THIRD SIGNAL RESPONSIVE MEANS DELIVERS A SIGNAL WHEN SAID SPECIFIC PORTION OF SAID TRACK IS IN PROXIMITY THERETO AND SAID FOURTH SIGNAL RESPONSIVE MEANS DELIVERS A SIGNAL WHEN ANY OF SAID PLURALITY OF SAID PORTIONS OF SAID TRACK ARE IN PROXIMITY THERETO; PULSE GENERATING MEANS; GATE MEANS; MEANS CONNECTING SAID GATE MEANS TO AN OUTPUT OF SAID PULSE GENERATING MEANS; MEANS CONNECTING SAID FIRST, SECOND, THIRD AND FOURTH SIGNAL RESPONSIVE MEANS TO SAID GATE MEANS FOR OPENING SAID GATE MEANS IN RESPONSE TO A SIGNAL FROM SAID FIRST OR SECOND SIGNAL RESPONSIVE MEANS AND CLOSING SAID GATE MEANS IN RESPONSE TO A SIGNAL FROM SAID THIRD OR FOURTH SIGNAL RESPONSIVE MEANS; PULSE COUNTING MEANS CONNECTED TO SAID GATE MEANS FOR COUNTING THE PULSES THERFROM; AND STORAGE MEANS CONNECTED TO SAID COUNTING MEANS FOR STORING A PULSE COUNT FROM SAID GATE MEANS BETWEEN SIGNALS FROM SAID FIRST AND THIRD SIGNAL RESPONSIVE MEANS AND FOR ALGEBRAICALLY SUMMING WITH SAID PULSE COUNT A FURTHER PULSE COUNT FROM SAID GATE MEANS BETWEEN SIGNALS FROM SAID SECOND AND FOURTH SIGNAL RESPONSIVE MEANS.