Patent ID: 8247725

Claim:
A vacuum switchgear comprising: a vacuum valve comprising a movable conductor having a movable contact, connected to an insulating rod, and a fixed conductor having a fixed contact, connected to a bus bar or to a load cable, wherein the contacts make an electrical contact and a separation therebetween; a vacuum chamber encasing the vacuum valve; an insulating envelope covering the vacuum chamber, the outer surface thereof being covered with an electro-conductive layer thereby to earth the envelope; and an insulating lid gas-tightly fitted to the insulating envelope, the lid having an insulating bushing through which an insulating rod, connected to the movable conductor of the vacuum valve, penetrates, the insulating rod being connected to an operating mechanism, wherein the insulating rod is slidably inserted into insulating bushing surrounding the insulating rod, and the insulating rod except a portion exposed from the bushing is gas-tightly confined in an insulating gas atmosphere formed between the insulating envelope and the insulating lid.