You can usually find these in public premises and commercial properties where heavy doors are installed.
Main functions performed by door closers:
Adjustable Closing Speed – This gives you the ability to adjust how fast or slow you want the door to close.
Adjustable Latch Action – Similar to the above, however this gives you the ability to adjust how fast or slow you want the door closing for the last few inches.
Delayed Action - This gives you the ability to adjust the delay of the door closing for an amount of time from maximum opening.
Back Check – This prevents damage made to the doors and walls by offering resistance when the door is opened with excessive force.
Hold Open – This allows the door to stay open at a certain angle. This is usually a 90 or 105 degree angle.
Overhead Closer
This is also known as a rack and pinion closer. An overhead door closer is one of the most common closers that are used. There are many variations of size, strength and ways to position the closer. You can also adjust the closing speed, latch action, delayed action and backcheck. Overhead door closers consist of a block body with an arm attached. Inside the body is a spring that is compressed as the door opens and released when the door closes.
Surface Spring Closer
Surface spring door closers are designed as a smaller efficient way of automatically closing lighter doors without all the added extras and abilities of an overhead door closer. These closers are fixed to the door frame and a wheel travels through the arm channel. The spring inside the body allows the door to close.
Floor Springs
A Floor Spring is a mechanical door closer, mainly used for glass doors where both a push and pull movement is required. Usually located in a cement box under the floor, this door closer consists of a heavy rectangle box with a cam spindle. An arm is attached to the spindle when fitted. When the door is opened it rotates the cam spindle and in turn the cam also rotates pulling the piston head. This causes the compression springs and oil inside to compress and store energy. When the door is released, the stored energy provides the closing action of the door.
Transom Closer
Also known as concealed overhead door closers, these door closers are fitted into the frame or ‘transom’ of the door. These closers work in much the same way as floor springs with compression springs and oil to store the energy needed to close the door. These closers are mainly used for glass or aluminium doors.