Shockproof shunt trip unit for tripping open the contacts of a circuit breaker

Claim 1

A SHOCKPROOF SHUNT TRIP UNIT FOR TRIPPING THE CONTACTS OF A CIRCUIT BREAKER FROM CLOSED CIRCUIT TO OPEN CIRCUIT POSITION, SAID TRIP UNIT COMPRISING: AN ELECTROMAGNET; AN ARMATURE MOVABLE IN RESPONSE TO ENERGIZATION OF SAID ELECTROMAGNET BETWEEN A FIRST POSITION IN WHICH SAID ARMATURE IS AWAY FROM SAID ELECTROMAGNET, AND A SECOND POSITION IN WHICH SAID ARMATURE IS DRAWN INTO ENGAGEMENT WITH SAID ELECTROMAGNET; A LATCH MEMBER MOVABLE BETWEEN A LATCHING AND TRIPPING POSITION, SAID LATCH MEMBER BEING LOCKED IN ITS LATCHING POSITION BY SAID ARMATURE TO PREVENT OPERATION OF CIRCUIT BREAKER AUTOMATIC TRIPPING MEANS WHEN SAID ARMATURE IS IN ITS FIRST POSITION, SAID LATCH MEMBER BEING MOVED TO ITS TRIPPING POSITION TO ACTUATE SAID CIRCUIT BREAKER AUTOMATIC TRIPPING MEANS WHEN SAID ARMATURE IS MOVED TOWARD ITS SECOND POSITION; AND A SINGLE BIASING MEANS SECURED TO BOTH SAID ARMATURE AND SAID LATCH MEMBER FOR MAINTAINING SAID ARMATURE IN ITS FIRST POSITION WHEN SAID ELECTROMAGNET IS IN ITS DEENERGIZED STATE, AND FOR MOVING SAID LATCH MEMBER TO ITS TRIPPING POSITION, IN RESPONSE TO MOVEMENT OF SAID ARMATURE TOWARD ITS SECOND POSITION.