Retractable security door

Abstract

The invention belongs to the field of doors for special purposes and particularly discloses an inward contracting type antitheft door. The inward contracting type antitheft door comprises an upper door beam, a lower door beam, a door post and a door shaft. The upper door beam and the lower door beam are telescopic rods. The inward contracting type antitheft door further comprises an inward concave four-bar mechanism and a pull wire. Placement portions made of scandium trifluoride are arranged at the two ends of the upper door beam. A groove is formed in the upper portion of the door shaft. One end of the lower door beam is connected to the bottom of the door post, and the other end of the lower door beam is connected to the lower portion of the door shaft in a sliding mode. The placement portions are placed on the door post and in the groove correspondingly. Four acting points of the inward concave four-bar mechanism are in sliding connection with the door post, the upper door beam, the lower door beam and the door shaft correspondingly. The door shaft is in sliding connection with a balance weight sleeve, the door shaft is provided with a fixing layer for fixing the balance weight sleeve on the door shaft, and the fixing layer is located between the door shaft and the balance weight sleeve and made of scandium trifluoride. One end of the pull wire is connected with the balance weight sleeve, and the other end of the pull wire is connected with the upper door beam. The problem that a room door cannot be opened after a fire occurs and consequently the escape function of the door under disaster conditions is affected in the prior art is solved.

Description

technical field [0001] The present invention is in the field of special purpose doors. Background technique [0002] The existing anti-theft door is deformed due to heat or force extrusion, and the door cannot be opened, especially in the case of a disaster, it is impossible to escape. Therefore, there is a need for a door structure with a retractable four-bar structure as the main body, so that when the door is under pressure, the two opposite sides can shrink in the same direction, avoiding the problem that the door cannot be opened. At the same time, considering the situation of heat exposure, plastic connectors are added, so that the door can ensure the escape function in case of disaster. [0003] The patent document whose authorized announcement is CN103899223B discloses a retractable anti-theft door, including a bolt support rod, a concave four-bar linkage mechanism, a sleeve, an inner door frame support telescopic rod, a horizontal connecting strip, and a longitudin...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a retractable anti-theft door to solve the problem in the prior art that the door cannot be opened after a fire and affects escape in case of a disaster

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