How does the door closer of a fire door work?

Time:2020-02-29 17:24:10

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How does the fire door closer work? When the door is opened, the door body drives the connecting rod to move the transmission gear to drive the rack plunger to the right. As the plunger moves to the right, the spring is compressed and the hydraulic oil in the right chamber is compressed. The check valve ball on the left side of the plunger opens under the action of oil pressure, and the right chamber hydraulic oil flows into the left chamber through the check valve. When the door opening process ends, the spring is compressed during the opening process, the accumulated elastic potential energy is released, the plunger is pushed to the left, the transmission gear and the door closer link are driven to rotate, and the door is closed.