The basic components of the hydraulic spring door closers are support guides, transmission gears, return springs, check valves, rack plungers, throttle bodies and housings, end caps, seals and connecting rods. The housing and linkage act as a fixed spring door closer and connect the door leaf and door frame.
The working principle of the floor spring door closer is: When the door is opened, the door body drives the connecting rod and rotates the transmission gear, which drives the rack plunger to move to the right. The spring is compressed during the movement of the plunger to the right and the hydraulic oil in the right chamber is also pressurized. The one-way valve ball on the left side of the plunger opens under the effect of oil pressure, and the hydraulic oil in the right cavity flows through the one-way valve to the left cavity. When the door opening process is completed, since the spring is compressed during the opening process, the accumulated elastic potential energy is released, the plunger is pushed to the left, and the transmission gear and the floor spring door closer link are rotated to close the door.
During the spring release process, since the hydraulic oil in the left chamber of the floor spring door closer is compressed, the one-way valve is closed, and the hydraulic oil can only flow out through the gap between the housing and the plunger and pass through the small hole in the plunger. And 2 flow passages equipped with a throttle valve return to the right chamber. Therefore, the hydraulic oil constitutes a resistance to the release of the spring, that is, through the throttling to achieve the buffering effect, the speed of closing the door is controlled. The throttle valve on the valve body can be adjusted to control the variable closing speed of the different stroke sections. Although the structure and size of floor spring door closers produced by different manufacturers are different, the principle is the same.
The types of floor spring door closers can be divided into: exterior and embedded door top spring door closers, embedded door middle floor spring door closers, door bottom floor spring door closers (floor springs), vertical Floor spring door closers (built-in vertical floor spring door closers) and other types of spring door closers.