| 摘要 |
An automatic open and closing system for a fire door is provided to open and close the fire door automatically in case of fire by operating an operation unit to interlocking with an adjusting body and a support body. An automatic open and closing system for a fire door comprises an arm(31), a support bolt(47), a spring(46), a hooking bolt(45), a support body(41), and an adjusting body(51). The arm has upper and lower rotation holes(32,33) at one end, and bushes(21,22) are inserted in the rotation holes. The support bolt is installed inside the arm. The hooking ball is contact with the support body. The adjusting body is provided with a toothed part formed around the edge of the bottom surface. A toothed part(43) formed on an upper surface of the support body engages with the toothed part of the adjusting body. When opening the door, the hooking ball is held by a hooking groove during rotation of the arm, thereby stopping the door. |
