Control system having a magnetic switch latching arrangement

Claim 1

A CONTROL SYSTEM FOR ACHIEVING A PREDETERMINED CONDITION IN THE TREATMENT OF ARTICLES COMPRISING : (A) FUNCTIONAL MEANS FOR CHANGING THE CONDITION OF THE ARTICLES TOWARD THE PREDETERMINED CONDITION; (B) A SWITCH HAVING AT LEAST ONE MEMBER OF MAGNETIC MATERIAL MOVABLE TO FIRST AND SECOND POSITIONS AND BIASED TO ITS FIRST POSITION, SAID SWITCH BEING ARRANGED TO CAUSE OPERATION OF SAID FUNCTIONAL MEANS IN SAID SECOND POSITION AND PRECLUDE OPERATION OF SAID FUNCTIONAL MEANS IN SAID FIRST POSITION; (C) A PERMANENT MAGNET FORMED AND POSITIONED TO PROVIDE A MAGNETIC FIELD EFFECTIVE BY ITSELF TO KEEP SAID SWITCH IN SAID SECOND POSITION ONCE IT HAS BEEN MOVED THERE BUT NOT EFFECTIVE BY ITSELF TO MOVE SAID SWITCH FROM ITS FIRST POSITION, (D) A COIL; (E) MEANS FOR INCREASING THE STRENGTH OF THE MAGNETIC FIELD PROVIDED TO SAID SWITCH SUFFICIENTLY TO MOVE SAID SWITCH FROM ITS FIRST POSITION TO ITS SECOND POSITION; (F) A DIRECT CURRENT CIRCUIT FOR ENERGIZING SAID COIL WITH A POLARITY SUCH AS TO PROVIDE AN ELECTROMAGNETIC FIELD OPPOSING SAID MAGNETIC FIELD, SAID COIL WHEN ENERGIZED IN SAID CIRCUIT DECREASING THE MAGNETIC FIELD TO THE POINT WHERE SAID SWITCH RETURNS TO ITS FIRST POSITION; (G) MANUALLY OPERABLE MEANS FOR PROVIDING OPERATION OF SAID FIELD STRENGTH INCREASING MEANS THEREBY TO MOVE SAID SWITCH TO ITS SECOND POSITION AND INITIATE OPERATION OF SAID FUNCTIONAL MEANS; (H) AND CONDITION RESPONSIVE MEANS FOR MOMENTARILY COMPLETING SAID COIL ENERGIZING CIRCUIT IN RESPONSE TO SUBSTANTIAL ACHIEVEMENT OF SAID PREDETERMINED CONDITION THEREBY TO RETURN SAID SWITCH TO ITS FIRST POSITION.