Electronically controlled electromagnetic safety battery cut-out for transport of dangerous or other materials

Claim 1

An electronically controlled battery electromagnetic cut-out unit for breaking a main electrical circuit and an auxiliary electrical circuit and being intrinsically safe, comprising a driving electromagnet having a pull winding, a hold winding, and a plunger core with a drive shaft; means for energizing the electromagnet to move the drive shaft in a first direction; an insulating intermediate member carried by the drive shaft; a central connecting member carried by the drive shaft for breaking the auxiliary circuit; a cross piece mounted on the drive shaft; a spring for urging the cross piece toward the intermediate member; a pair of lateral connecting bars; insulating means coupling the connecting bars to the cross piece; return springs for urging the connecting bars and the cross piece against the first direction movement of the drive shaft; means defining four terminal locations; the connecting bars in the energized state of the electromagnet being applied against the four terminal locations and in the deenergized state being urged away from the four terminal locations to provide main single to two-pole break control of the circuitry of the four terminal locations; control electronics including a voltage regulator, a control line for supplying voltage to the voltage regulator, a monostable multivibrator connected to the voltage regulator to be supplied therefrom, a first amplifier coupling a first output of the multivibrator to the pull winding, and a second amplifier coupling a second output of the multivibrator to the hold winding; and a sealed case enclosing the unit.