Synchro-to-digital converter

Claim 1

A SYNCHRO-TO-DIGITAL CONVERTER COMPRISING; INPUT MEANS ADAPTED TO RECEIVE A SYNCHRO SIGNAL; SAID SIGNAL CONTAINING POSITION INFORMATION FROM A REMOTE ROTATING SHAFT; ANOTHER INPUT MEANS ADAPTED TO RECEIVE A REFERENCE SIGNAL FROM THE AFORESAID ROTATING SHAFT; ERROR DETECTION MEANS OPERATIVELY COUPLED TO SAID INPUT AND SAID OTHER INPUT FOR COMPARING THE SYNCHRO SIGNAL AND THE REFERENCE SIGNAL; SAID ERROR DETECTION MEANS OPERATING TO DETERMINE THE PHASE RELATIONSHIP OF THE SYNCHRO SIGNAL TO THE REFERENCE SIGNAL AND THE AMPLITUDE OF THE ERROR BETWEEN THE REFERENCE AND THE SYNCHRO SIGNALS; CONVERTER MEANS RECEIVING THE OUTPUT OF SAID ERROR DETECTION MEANS FOR CONVERTING SAID OUTPUT TO PULSES INDICATING A DIRECTION COMMENSURATE WITH SAID PHASED RELATIONSHIP AND AT A PULSE RATE WHICH IS A FUNCTION OF THE AMPLITUDE OF ERROR BETWEEN SAID SYNCHRO SIGNAL AND THE REFERENCE SIGNAL; CONTROL LOGIC MEANS CONNECTED TO RECEIVE SAID PULSES FOR PRODUCING A DIRECTIONAL PULSE DRIVE SIGNAL; DRIVE MEANS CONNECTED TO SAID INPUT MEANS AND RESPONSIVE TO SAID DRIVE SIGNAL FOR POSITIONING SAID INPUT MEANS IN ACCORDANCE WITH THE DIRECTIONAL SENSE AND PULSE RATE OF SAID DRIVE SIGNAL; A BI-DIRECTIONAL DIGITAL COUNTER MEANS CONNECTED TO RECEIVE THE PULSE OUTPUT OF SAID CONVERTER AND BEING RESPONSIVE THERETO FOR PRODUCING A DIGITAL READOUT INDICATIVE OF THE ROTATIONAL POSITION OF SAID INPUT MEANS; AND A ZERO DETECTOR RESPONSIVE TO A PREDETERMINED POSITION OF SAID INPUT MEANS FOR PRODUCING A REST SIGNAL OPERATIVE TO RESET SAID BI-DIRECTIONAL DIGITAL COUNTER UPON PASSING THROUGH SAID PRE-DETERMINED POSITION.