Through-bolt joint for bus duct

Claim 1

IN COMBINATION A FIRST, A SECOND, A THIRD AND A FOURTH BUS BAR AND JOINT MEANS FOR EFFECTING ELECTRICAL CONNECTIONS OF SAID FIRST AND SAID SECOND BUS BARS TO SAID THIRD AND FOURTH BUS BARS, RESPECTIVELY; SAID JOINT MEANS BEING COMPRISED OF AN INSULATING MEANS AT LEAST A FIRST PORTION OF WHICH IS RIGID AND POSITIONED IN THE REGION INTERMEDIATE ELECTRICALLY ISOLATED ONES OF SAID BUS BARS AND IN DIRECT CONTACT WITH AT LEAST ONE BUS BAR FROM THE RESPECTIVE ONES OF SAID ELECTRICALLY CONNECTED BUS BARS TO ESTABLISH THE MINIMUM SPACING IN THE REGION OF SAID JOINT MEANS BETWEEN SAID FIRST AND SAID SECOND BUS BARS AS WELL AS BETWEEN SAID THIRD AND SAID FOURTH BUS BARS; SAID FIRST AND THIRD BUS BARS AND SAID SECOND AND FOURTH BUS BARS INCLUDING COOPERATING PORTIONS ADJACENTLY POSITIONED TO BE URGED INTO GOOD ELECTRICAL ENGAGEMENT BY SAID INSULATING MEANS FIRST PORTION; SAID JOINT MEANS ALSO INCLDING A BOLT MEANS EXTENDING THROUGH AN OPENING IN SAID INSULATING MEANS; SAID BOLT MEANS WHEN TIGHTENED URGING SAID INSULATION MEANS FIRST PORTION AGAINST SAID BUS BARS THEREBY ESTABLISHING CONTACT PRESSURE FOR THE ELECTRICAL CONNECTIONS BETWEEN THE RESPECTIVE ONES OF SAID BUS BARS; AN INSULATING TUBE DISPOSED WITHIN SAID INSULATING MEANS OPENING AND INTERPOSED BETWEEN SAID BOLT MEANS AND SAID INSULATING MEANS; SAID FIRST AND SAID SECOND BUS BARS HAVING ALIGNED OPENINGS; SAID THIRD AND SAID FOURTH BUS BARS HAVING OPEN-ENDED SLOTS; SAID INSULATING TUBE EXTENDING THROUGH SAID ALIGNED OPENINGS AND SAID SLOTS; SAID INSULATING MEANS INCLUDING A SECOND PORTION INTERPOSED ADJACENT SELECTED ONES OF SAID BUS BARS AND ABOUT SAID INSULATED TUBE; SAID SECOND PORTION EXTENDING FROM THE INTERSECTION OF SAID INSULATED TUBE AND SAID SELECTED BUS BAR AND IN THE AXIAL DIRECTION OF SAID INSULATED TUBE, THEREBY PROVIDING INCREASED ELECTRICAL ISOLATION.