The working principle is simple closed door is similar to a spring hydraulic device on the door, when we open the door, door closers can be compressed after release, finally the door automatically closed. Among them the action of the spring is we can guarantee that after the door was opened can be timely and accurate to a a state at the time of being closed.
The invention of door closer
Now we said before closing this we call the hydraulic closers, was founded in America in early twentieth Century. The design of the core hydraulic door closer is achieved to the control door can close, thus can limit the fire spread as fire ventilation places.
he working principle of door closer
When opening the door, the door body drives the connecting rod rotation and use the drive gear, drive rack column will be moved to the right. The compression of the spring in the process of the shift in the piston, the hydraulic oil right in the cavity will also be oppressed. On the left side of the ball plunger one-way valve on the oil pressure in the hydraulic open oil right cavity through the one-way valve flow in the cavity. When the door is left after the process finished, because the spring is in the process of open compression, the elasticity of savings will be released, will push the plunger to the left, the connecting rod drives the drive gear and closer rotation, so that the door is closed.
The work of the door closer is a little bit more professional, but a closer look should help you understand. What else does the closure involve?
Support guide, drive gear, reset spring, check valve, rack plunger, stop valve and housing, end cap, seal ring and connecting rod
The article by Fulda closers finishing cloth
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