You will find 3 styles of automatic door closer available within the market today. Based on the weight from the door and how you intend use it there is a perfect style of doorway better for you to select from. Probably the most common type may be the spring loaded door better or hinge pin doorway closer which are effective for light applications.

Suitable for light weight doors like outdoor patio doors that is normally created of lightweight aluminum frame with mesh screen covering almost half of it. This door closer is commonly created of aluminum tubing or cylinder with only the push rod exposed while the spring is covered on the inside. The principle used is really basic, a spring system pulls the door with a small tension and whenever you open it more tension from the string is generated which force the door to close when released. The frequent issue with spring loaded door closer is that the push rod can be easily damaged if not installed properly or should you open the door excessively. Also the piston rod bearing or bushing in the front end which absorbed the linear load wears in the long run.

One more type of door closer is the pneumatic door closer. They're very identical to their spring loaded cousins with respect to load capacity and overall look. It also utilizes the exact same aluminum tube frame and has a piston rod. The main difference is that it uses pressurized air instead of springs that is created whenever you open the door compressing the air within then pulls and close the door when you release it. Also the internal design is a bit different.

In the spring loaded door closer there is no rubber seal around the piston or it is not air tight while in pneumatic doorway closer, a rubber seal is installed to keep the air from getting out. Without the rubber seal to hold the air pressure or when it is broken will make the device ineffective. Additionally the internal surface of the aluminum cylinder is mirror polished for smooth functioning and to extend the life of the rubber seal and also the device itself. Since the air is compressible this form of door closer has the tendency of slamming the door if not correctly adjusted.

The last type of automatic door closer is the hydraulic oil filled door closer. This form may be the most reliable and toughest among the three. It also has a very different design and mounting structure compared to the other. While the spring loaded and pneumatic door closer is installed at the side from the door, around the hinge, the hydraulic type is applied in the top part of the door. It is best to use in large weight doors and is normally used in front doors or primary doors. The closing speed is adjustable with the turn of the screw. With the mounting template (to mark holes for drilling) and installation instruction bundled in the package making it very easy to set up (drill necessary) and doesn't require a specialist to do them. Unlike pneumatic air, hydraulic fluid isn't compressible, so, it's feasible to correct the closing from the door at a really low speed and smoothly.

There are also some other types of automatic door closer including the motorized automatic door closer. Really it's not only for closing but for opening too that is really handy for hands free, disabled and handicap access. This system utilizes a 24 VDC motor to operate and controlled by a microprocessor which allows you to open and close the door both by hand and automatically. The encoder that is coupled towards the DC motor detects the angle from the door at all times, which means the encoder can determine if the door is open and how a lot and reacts accordingly. In contrast to non electric door closer it is more expensive and cost close to 1.5k USD and probably hard to maintain because of lots of moving parts and certainly needed a professional technician to install.