Plunger operated photoelectric switch convertible from normally on to normally off

Claim 1

A CONTACTLESS SWITCHING DEVICE COMPRISING A SUBSTANTIALLY LIGHT-TIGHT ENCLOSURE, A PHOTOELECTRIC CELL, AN ELECTRICAL LAMP, MEANS POSITIONING SAID PHOTOELECTRIC CELL AND SAID LAMP WITH RESPECT TO EACH OTHER WITHIN SAID ENCLOSURE SO THAT LIGHT FROM SAID LAMP CAN IMPINGE ON SAID PHOTOELECTRIC CELL THROUGH A PATH, SAID PHOTOELECTRIC CELL EXHIBITING A CHANGE IN ITS ELECTRICAL CHARACTERISTICS UPON A CHANGE IN THE AMOUNT OF LIGHT IMPINGING THEREON, A FIRST TERMINAL MEANS FOR APPLYING A SOURCE OF POTENTIAL FOR ENERGIZING SAID LAMP, A SECOND TERMINAL MEANS CONNECTED TO SAID PHOTOELECTRIC CELL SO AS TO BE RESPONSIVE TO SAID CHANGE IN SAID ELECTRICAL CHARACTERISTICS OF SAID PHOTOELECTRIC CELL, OPERATOR MEANS FOR CONTROLLING THE AMOUNT OF LIGHT FROM SAID LAMP IMPINGING ON SAID PHOTOELECTRIC CELL, SAID OPERATOR MEANS INCLUDING A CYLINDRICAL MEMBER INTERPOSED IN SAID PATH, RECIPROCATIVE LINEARLY BETWEEN AN ACTUATED AND AN UNACTUATED POSITION, AND HAVING A PAIR OF CIRCUMFERENTIALLY SPACED AND AXIALLY UNALIGNED APERTURES THEREIN, AND INDEXING MEANS OPERATIVE TO RETAIN SAID MEMBER IN A FIRST AND SECOND TURNED POSITION SELECTIVELY, THE AXIAL POSITION AND SIZE OF ONE OF SAID APERTURES BEING SUCH THAT, WHEN SAID MEMBER IS IN SAID FIRST TURNED POSITION, LIGHT FROM SAID LAMP IMPINGES ON SAID PHOTOELECTRIC CELL WHEN SAID MEMBER IS IN SAID UNACTUATED POSITION AND SAID MEMBER PREVENTS LIGHT FROM SAID LAMP IMPINGING ON SAID PHOTOELECTRIC CELL WHEN SAID MEMBER IS IN SAID ACUATED POSITION, AND THE AXIAL POSITION AND SIZE OF THE OTHER OF SAID APERTURES BEING SUCH THAT, WHEN SAID MEMBER IS IN SAID SECOND TURNED POSITION, LIGHT FROM SAID LAMP IMPINGES ON SAID PHOTOELECTRIC CELL WHEN SAID MEMBER IS IN SAID ACTUATED POSITION AND SAID MEMBER PREVENTS LIGHT FROM IMPINGING ON SAID PHOTOELECTRIC CELL WHEN SAID MEMBER IS IN SAID UNACTUATED POSITION.