Apparatus for and method of identifying material units

Claim 1

MATERIAL-UNIT IDENTIFYING APPARATUS FACILITATING PERFORMANCE OF A DESIRED FUNCTION IN RELATION TO THE EXISTENCE OF A MATERIAL-UNIT AT A PREDETERMINED POSITION, SAID APPARATUS COMPRISING: (A) A CONVEYING MEDIUM; (B) A SECOND MEDIUM; (C) MEANS PRODUCING MOVEMENT OF THE CONVEYING MEDIUM ALONG THE SECOND MEDIUM, ONE OF SAID MEDIA BEING ADAPTED TO SUPPORT THE MATERIAL-UNITS; (D) MAGNETIC MEANS DEFINING MAGNETIZED AREAS WITH THE AXIS OF EACH MAGNETIC AREA DEFINED BY ITS POLES PARALLEL TO THAT OF ALL OTHERS, SAID MEANS BEING SUPPORTED BY ONE OF THE MEDIA IN PREDETERMINED RELATION TO THE MATERIAL-UNITS WHEN THE LATTER ARE SO SUPPORTED; (E) A MAGNETIC SENSING MEANS SENSING THE POLARITY OF SAID MAGNETIZED AREA WHEN THE LATTER IS DISPOSED ADJACENT THERETO AND PRODUCING OUTPUT SIGNALS IN ACCORDANCE THEREWITH, SAID MAGNETIC SENSING MEANS BEING SUPPORTED BY THE OTHER OF THE MEDIA AND INCLUDING AN UNBIASED MAGNETIC MULTI-POLARITY-SENSITIVE SENSING HEAD CAPABLE OF DETECTING TWO DIFFERENT POLARITIES OF SAID MAGNETIZED AREAS AT ANY ONE TIME AND PRODUCING OUTPUT SIGNALS OF PREDETERMINED MAGNITUDE REPRESENTATIVE OF EITHER POLARITY SENSED, SAID SENSING HEAD BEING IMMOVABLY POSITIONED IN SPACED AND CONFRONTING RELATION WITH SAID MAGNETIZED AREAS; (F) ALTERNATING CURRENT EXCITATION MEANS OPERABLY CONNECTED TO THE SENSING HEAD OF SAID SENSING MEANS; (G) AND SELECTIVE CIRCUIT MEANS PRODUCING A SIGNAL OF PREDETERMINED MAGNITUDE SUFFICIENT TO INITIATE THE PERFORMANCE OF THE DESIRED FUNCTION TO BE PERFORMED, SAID CIRCUIT MEANS BEING OPERABLY CONNECTED TO SAID MAGNETIC SENSING HEAD AND RESPONSIVE TO SAID OUTPUT SIGNALS FROM SAID SENSING HEAD.