| 摘要 |
A plug member, which is to be used for a low-temperature storage including: a heat-insulating door to close an opening face of a heat-insulating housing; a cooling device; and a through-hole passing through a heat-insulating wall in the housing and having an internal thread on an inner periphery thereof, and which closes an opening portion of the through-hole on an outer side of the storage, includes: an external thread to be threadedly engaged with the internal thread; and a flange member to abut onto a face having the opening portion and close the portion, by threaded engagement between the external and internal threads, the external thread having a cut, which opens a part of the opening portion, formed in a portion of an outer periphery thereof, in a state where the flange member does not abut on the face, while the external thread is threadedly engaged with the internal thread. |
