How much do you know about door closers?

The door closer is a spring-like hydraulic device on the door head. When the door is opened, it can be released after compression and automatically close the door. It has a function like a spring door, which can ensure that the door is accurately and timely closed to the initial position after being opened. .

Modern hydraulic door closers (referred to as door closers) began with a patent registered by Americans in the early twentieth century. It is different from traditional door closers. It buffers the liquid in the door closer to achieve a buffering effect. . The core of the design concept of the hydraulic door closer is to realize the control of the door closing process, so that various functional indicators of the door closing process can be adjusted according to human needs.

The significance of the door closer is not only to automatically close the door, but also to protect the door frame and door body (steady closing), and more importantly, the door closer has become a non-negligible execution part of the intelligent management of modern buildings.

Door closers are mainly used in commercial and public buildings, but are also used in homes. They have many uses, the most important of which is to close the door by itself to limit the spread of fire and ventilation in the building.

Working principle
The basic components of hydraulic door closers include support guides, transmission gears, return springs, check valves, rack plungers, throttle spools and housings, end covers, sealing rings and connecting rods. The shell and the connecting rod play the role of fixing the door closer and connecting the door leaf and the door frame.

The working principle of the door closer is: when the door is opened, the door body drives the connecting rod to move, and causes the transmission gear to rotate, driving the rack plunger to move to the right. As the plunger moves to the right, the spring is compressed and the hydraulic oil in the right chamber is also compressed. The ball of the one-way valve on the left side of the plunger opens under the action of oil pressure, and the hydraulic oil in the right chamber flows into the left chamber through the one-way valve. When the door opening process is completed, due to the compression of the spring during the opening process, the accumulated elastic potential energy is released, pushing the plunger to the left, driving the transmission gear and door closer connecting rod to rotate, closing the door.

During the spring release process, because the hydraulic oil in the left cavity of the door closer is compressed, the check valve is closed, and the hydraulic oil can only flow out through the gap between the housing and the plunger, and through the small hole on the plunger and 2 The flow channel equipped with a throttle spool returns to the right cavity. Therefore, the hydraulic oil constitutes resistance to the spring release, that is, the damping effect is achieved by throttling, and the speed of the door closing is controlled. The throttle valve on the valve body can be adjusted to control the variable closing speed of different stroke sections. Although the structure and size of door closers produced by different manufacturers are different, the principle is the same.

The types of door closers can be divided into: exterior and in-line door top door closers, in-line door middle door closers, door bottom door closers (floor springs), vertical door closers (built-in vertical door closers) Uşă) and other types of door closers.

Post time: 2020-06-22