A door may be provided with a door closer configured to automatically close the door from an open position without further input from a user. A door closer typically includes an energy storage device configured to store energy imparted to the door when it is opened and to use the stored energy to close the door when it is released.
A door closer may be embodied as nothing more than a helical tension spring connected between the door and a mating door frame. Such a door closer has several drawbacks. For example, the bare spring may pinch a user when it retracts. Also, the spring may be exposed to the elements and become dirty or corroded as a consequence. Once dirtied or corroded, it may be difficult to clean. Even if clean and uncorroded, the spring may be unsightly. Further, the coils of the spring may routinely come into contact with, drag across, and abrade the edge of the door when the door is opened and closed.
Alternatively, a door closer may be embodied as a pneumatic tube including a cylinder connected to the door and a piston connected via a piston rod to the door jam. Such a door closer typically has a high profile, and may project away from the door and into adjacent living space. Also, such a door closer might not be aesthetically pleasing.
Some door closers include a hydraulic mechanism attached to a door and a linkage connecting the hydraulic mechanism to a door jam. Such door closers also have a high profile, and they can be unattractive and costly.
USPTO Backgrounds
USPTO Backgrounds