Electrical control circuits

Claim 1

A CIRCUIT FOR ENERGIZING A WORK DEVICE TO CONTROL A CYCLICALLY OPEATING MACHINE COMPRISING A FIRST, SECOND, THRID, AND FOURTH CONTACTOR; EACH CONTACTOR HAVING A PLURALITY OF NORMALLY OPEN AND NORMALLY CLOSED CONTACTS; A FIFTH CONTACTOR HAVING NORMALLY CLOSED CONTACTS; A FIRST AND SECOND MACHINE OPERATED LIMIT SWITCH, EACH LIMIT SWITCH HAVING CONTACTS SET TO OPERATE AT VARIOUS PRESELECTED POINTS IN THE MACHINES OPERATING CYCLE; A SOURCE OF ELECTRICAL POWER FOR ENERGIZING THE CONTACTOR AND THE WORK DEVICE, AND CONNECTED TO THE CIRCUIT THROUGH NORMALLY CLOSED FIRST CONNECTED OF BOTH LIMIT SWITCHES, EACH NORMALLY COLSED CONTACT HAVING A NORMALLY OPEN CONTCT OF ITS RESPECTIVE LIMIT SWITCH CONNECTED IN PARALLEL THEREWITH; AN OPERATOR PUSH BUTTON HAVING A NORMALLY OPEN AND A NORMALLY CLOSED CONTACT; SAID FIRST CONTACTOR TO BE CONNECTED TO ENERGIZE THROUGH THE NORMALLY CLOSED CONTACT OF THE PUSH BUTTON; SAID FIFTY CONTACTOR CONNECTED TO BE ENERGIZED THROUGH THE NORMALLY CLOSED CONTACT OF THE PUSH BUTTON, A NORMALLY OPEN CONTACT OF THE FIRST CONTACTOR AND NORMALLY OPEN CONTACT OF THE PUSH BUTTON; SAID SECOND CONTACTOR ENERGIZED THROUGH A NORMALLY OPEN CONTACT OF SAID FIRST CONTACTOR AND SUSTAINED ENERGIZED THROUGH ONE OF ITS OWN NORMALLY OPEN CONTACTS AND A NORMALLY CLOSED CONTACTS OF SAID THRID CONTACTOR; AND UPON DEPRESSION OF SAID PUSH BUTTON SAID FIRST CONTACTOR IS DE-ENERGIZED AND SAID THIRD CONTACTOR IS ENERGIZED THROUGHT THE NORMALLY OPEN CONTACT OF THE PUSH BUTTON, A NORMALLY CLOSED CONTACT OF SAID FIRST AND FIFTH CONTACTORS, AND A NORMALLY OPEN CONTACT OF SAID SECOND CONTACTOR, AND SUSTAINED ENERGIZED THROUGH ONE OF ITS NORMALLY OPEN CONTACTS; AND AFTER THE THIRD CONTACTOR IS ENERGIZED, THE SECOND CONTACTOR IS DE-ENERGIZED BY THE OPENING OF SAID NORMALLY CLOSED THRID CONTACTOR CONTACT IN ITS SUSTAINING CIRCUIT; SAID FOURTH CONTACTOR IS ENERGIZED THROUGH THE NORMALLY OPEN CONTACT OF THE PUSH BUTTON, A NORMALLY CLOSED CONTACT OF THE FIRST AND SECOND AND FIFTH CONTACTORS, AND A NORMALLY OPEN CONTACT OF THE THRID CONTACTOR; AND SAID WORK DEVICE IS ENERGIZED THROUGH THE NORMALLY OPEN CONTACT OF SAID PUSH BUTTON, A NORMALLY CLOSED CONTACT OF SAID FIRST AND SECOND AND FIFTH CONTACTORS, AND A NORMALLY OPEN CONTACT OF SAID THRID AND FOUTH CONTACTORS TO OPERATE THE MACHINE WHEREBY SAID SECOND CONTACTS OF THE LIMIT SWITCHES ARE OPERATED TO CLOSE AND IMMEDIATELY THEREAFTER SAID FIRST CONTACTS OF THE LIMIT SWITCHES ARE OPERATED TO OPEN AND RECLOSE, AND SAID SECOND CONTACTS ARE OPERATED TO REOPEN TO THEREBY DE-ENERGIZE THE CIRCUIT AND STOP THE MACHINE SHOULD EITHER OF THE LIMIT SWITCHES NOT BE OPERATING PROPERLY.