| 摘要 |
The objective of the present invention is to eliminate, through an inexpensive constitution, deterioration in withstand voltage performance and deterioration in current passage performance caused by heating, in a vacuum circuit breaker. This vacuum circuit breaker comprises: a main circuit structure body comprising a vacuum circuit breaker insulation rod (6), a vacuum valve (8), a mobile side terminal (7a), and the like; and an insulating holder (1) supporting this main circuit structure body. The shape of the insulating holder (1) is a frame structure body provided with opening portions (5a, 5b, 5c, 5d) on the top, bottom, and both side surfaces thereof at the site where the vacuum valve (8) is disposed and at the site where the insulation rod (6) is disposed. |
