Tank-type circuit breaker

A circuit breaker, comprising:

• a cylindrical grounded tank in which an insulating gas is sealed;
• a contact insulated and supported in the grounded tank and including a movable-side contact and a fixed-side contact;
• a movable conductor electrically connected to the movable-side contact;
• a fixed conductor electrically connected to the fixed-side contact;
• a movable-side external conductor and a fixed-side external conductor disposed in a pair of bushings extending above the grounded tank, respectively;
• a movable-side frame configured to electrically connect a lower end of the movable-side external conductor to the movable conductor;
• a fixed-side frame configured to electrically connect a lower end of the fixed-side external conductor to the fixed conductor;
• a movable-side insulating support tube configured to insulate and support the movable-side frame in the grounded tank;
• an annular portion formed of an annular plate and fixed at an outer peripheral portion to the fixed-side frame inside the fixed-side frame;
• a rod fixed to a distal end portion of the fixed-side external conductor and extending in an extending direction of the fixed-side external conductor;
• and
• an annular suppressing plate fixed at a central portion to a distal end portion of the rod, wherein
• the fixed-side frame and the fixed-side external conductor are connected via at least two elastics arranged in series along the extending direction of the fixed-side external conductor, so that the fixed-side frame is suspended and supported by the fixed-side external conductor, and wherein
• the elastics include a first elastic and a second elastic configured to generate, when compressed, a reaction force in a direction opposite to a compressed direction;
• the first elastic is disposed between the fixed-side external conductor and the annular portion;
• and
• the second elastic is disposed between the annular portion and the annular suppressing plate.