To provide a door closing device usable in place of a lock to prevent the intrusion of a suspicious person.
The door closing device for maintaining a vestibule door 20 mounted in an openable/closable manner to an opening of a vestibule frame 30 comprises a suction cup 11 provided on the vestibule frame 30 side to form a space between the edge part of the opening and the vestibule door 20 into a closed space 11d when the vestibule door 20 is in the closed position, and a hose 12 and a suction pump 14 for sucking air in the closed space 11d. The sucker 11 is formed of an elastic member to widen from a base part toward the tip part which abuts on a suction face. The hose 12 is provided with a valve 13 preventing back flow from the suction pump 14 side.
JP2006063529 | HYDRAULIC INTERLOCK SYSTEM |
WO/2021/203303 | NOVEL CONTAINER HOISTING APPARATUS |
WO/1994/022736 | TIME CAPSULE |
FUJITA HIROSHI
JPS63122881A | 1988-05-26 | |||
JP2002036055A | 2002-02-05 | |||
JPH07267410A | 1995-10-17 | |||
JPH08334540A | 1996-12-17 |
Mikio Hotta