To seal hermetically the gap between the packing under a door and a floor face when the door is closed and raise the packing up to such a height that it does not rub the floor face when the door is opened.

A pin is fitted in the sleeve of the upper hinge wings so as to be vertically adjustable and a hinge is inserted to support the weight of the door, in the sleeve of the lower hinge wings through a spring. The cam face of a guide member 56 fitted to the upper end of the door 14 attached to a frame through the hinge comes into contact with the roller 63 of a metal tool 58 fixed to the lower part of the upper frame 57 to push down the door against the built-in spring in the hinge. In this way, the packing 64 under the door is closely stuck on the floor face 66.