Electrical apparatus

Claim 1

A CONTROL SYSTEM COMPRISING A FIRST CIRCUIT, A SECOND CIRCUIT, A THIRD CIRCUIT, AND A SWITCH OPERABLE SELECTIVELY TO DEENERGIZE SAID THREE CIRCUITS SIMULTANEOUSLY, TO ENERGIZE ONLY THE FIRST CIRCUIT, OR TO ENERGIZE THE FIRST AND SECOND CIRCUITS SIMULTANEOUSLY, AND OPERABLE SELECTIVELY TO ENERGIZE THE THIRD CIRCUIT SIMULTANEOUSLY WITH EITHER THE ENERGIZATION OF THE FIRST CIRCUIT OR WITH THE SIMULTANEOUS ENERGIZATION OF THE FIRST AND SECOND CIRCUITS, SAID SWITCH COMPRISING A STATOR HAVING A FIRST SET OF CONTACTS COMPRISING A FIRST CONTACT IN SAID FIRST CIRCUIT, A SECOND CONTACT IN SAID SECOND CIRCUIT, AND A THIRD CONTACT IN SAID THIRD CIRCUIT, A SWITCH ELEMENT WHICH MAY BE SELECTIVELY MOVED RELATIVE TO THE STATOR TO FIRST, SECOND, AND THIRD POSITIONS, SAID MOVABLE SWITCH ELEMENT HAVING A SECOND SET OF CONTACTS AT LEAST ONE OF WHICH ENGAGES THE FIRST CONTACT IN THE THIRD POSITION OF THE MOVABLE SWITCH ELEMENT AND AT LEAST ONE OF WHICH ENGAGES THE SECOND AND FIRST CONTACTS IN THE THIRD AND SECOND POSITIONS RESPECTIVELY OF THE MOVABLE SWITCH ELEMENT, THE MOVABLE SWITCH ELEMENT HAVING A FOURTH CONTACT CONFRONTING THE THIRD CONTACT WHEN THE MOVABLE SWITCH ELEMENT IS IN ITS THIRD AND SECOND POSITIONS, MEANS CONNECTING THE SECOND SET OF CONTACTS AND THE FOURTH CONTACT TO ONE SIDE OF A CURRENT SOURCE, THE MOVABLE SWITCH ELEMENT BEING MOUNTED FOR RELATIVE AXIAL MOVEMENT TOWARD AND AWAY FROM THE STATOR, THE CONTACTS OF BOTH SETS BEING SO CONSTRUCTED AND ARRANGED AS TO MAINTAIN THE RECITED ENGAGEMENT THEREBETWEEN AT SAID SECOND AND THIRD POSITIONS REGARDLESS OF THE AXIAL MOVEMENT OF THE MOVABLE SWITCH ELEMENT TOWARD AND AWAY FROM THE STATOR, THE THIRD AND FOURTH CONTACTS BEING SO CONSTRUCTED AND ARRANGED THAT IN THE THIRD AND SECOND POSITIONS THEY ARE OUT OF ENGAGEMENT WHEN THE MOVABLE SWITCH ELEMENT IS MOVED AXIALLY TO A FIRST TERMINAL POSITION WITH RESPECT TO THE STATOR AND ARE IN ENGAGEMENT WHEN THE MOVABLE SWITCH ELEMENT IS MOVED AXIALLY TO THE SECOND TERMINAL POSITION WITH RESPECT TO THE STATOR.