Door closer

A door closer is a mechanical device that regulates the speed and action of a door’s swing. Manual closers store the force used to open the door in some type of spring and reuse it to close the door. Automatic types use electricity to regulate door swing behavior.

Door closers can be linked to a building's fire and security alarm systems.

One of the first references concerning a device to close a door can be found in the writings of Hero of Alexandria who describes his "automata" which controlled the doors of temples, both opening and closing them automatically. Weights and levers have also been used to close doors. Another device for smaller domestic doors used a loop of rope or skein fixed to the door frame, that was twisted, with a piece of wood placed in between the twists to push the door. The opening of the door twists the skein further, when the door is released the rope's torsional force pushes the arm back against the door, thereby closing it.

In more modern times the clock manufacturers Thwaites and Reed in 1850 claimed to be the original inventors of the spiral door spring. The earliest English patent for a door closing device consisting of weights and pulleys was issued in 1786 to Francis Moore. The first English patent issued that mentions a spring can be traced to a few years later to that of Henry Downer. (Ironmonger) of Fleet Street, London recognised for the invention of a "spring to shut a door" (1790). There were even earlier devices invented to close a door, for instance, Mr Delevitz's model of a door with spiral spring hinges (1768). Earlier still is reference by way of a letter between Sir Edward Filmer (3rd Bart.) and his brother, Beversham Filmer dated 1748, in which they discuss a door spring. A mechanical statue reportedly displayed by a Monsieur Delanois at the White Swan in Stamford on December 21, 1736, was said to open and close its own door.{{citation needed}}

The first door closers consisted of just a spring mechanism only, as time went on the rate at which the door closed was arrested or checked by adding an additional checking device. Door closers at this time were known as a door spring and check. Later these two devices were combined into one unit that both closed the door and slowed the speed at which this was done. These early "door closers" used a pneumatic piston to check the speed, later models used a hydraulic or oil filled device for the same effect.

The first patent for a pneumatic device to prevent the sudden slamming of a door was given to William Bullock and James Boaz, on May 13, 1813 (Patent Number 3695). An improved hydraulic device to prevent the "clapping" (slamming) of doors was patented by William Overden Snr and William Overden Jnr in 1864. Door closers that utilize the properties of vulcanised Indian rubber have also been patented and used.

The use of door closers expanded during the Victorian era. Companies such as William Tonks and Son, James Cartland and Sons, and William Newman and Son were based in and around Birmingham. It has been claimed that one of these firms received an award in 1974 for producing their one millionth door closer, although a reliable source for this has not been identified.[citation needed] In 1907 the Briton B was first placed on the market.

In the United States, Lewis. C. Norton started his business in 1877, entering the door closer market in 1880 with a door check for the Trinity Church, Boston. Eugene Blount, Francis Richards and Joseph Bardsley also played important parts in the development, improvement and commercialization of door closers along with other companies, including Yale, Norton, Rixson and The Shelby Spring Hinge Company.