Insulator covered with a protective envelope

Claim 1

AN INSULATOR COMPRISING A FIRST CENTRAL TERMINAL ELEMENT MADE OF ELECTRICALLY CONDUCTIVE MATERIAL, A SECOND CENTRAL TERMINAL ELEMENT MADE OF ELECTRICALLY CONDUCTIVE MATERIAL, A SUBSTANTIALLY RIGID DIELECTRIC MATERIAL BINDING A PORTION OF SAID FIRST AND SECOND TERMINAL ELEMENTS TOGETHER IN A FIXED RELATIVE POSITION WHEREIN SAID TERMINAL ELEMENTS ARE SPACED AND INSULATED FROM EACH OTHER BY SAID DIELECTRIC MATERIAL TO PROVIDE A SPACED JUNCTURE, AN ENVELOPE MADE OF ELECTRICALLY NONCONDUCTIVE, WATER REPELLANT, FLEXIBLE MATERIAL SEALINGLY ENGAGED AT OPPOSITE ENDS TO SAID FIRST AND SECOND CENTRAL TERMINAL ELEMENTS RESPECTIVELY, AND SPACED FROM THE JUNCTURE OF SAID TERMINALS AND THE DIELECTRIC BINDER MATERIAL WHICH ARE COMPLETELY ENCAPSULATED BY SAID ENVELOPE, WHEREIN SAID ENVELOPE IS FORMED WITH ADJACENT ALTERNATIVELY VARYING EXPANSION MEANS WHICH CAUSE IT TO EXPAND AND TO CONTRACT AUTOMATICALLY IN RESPONSE TO ATMOSPHERIC TEMPERATURE VARIATIONS SO AS TO SUBSTANTIALLY DISLODGE DUST PARTICLES SETTLING THEREON.