How do Garage Door Openers Work?

All garages have doors that slide up or down when a car enters the garage. This garage door is operated by a motorized system that can either be worked remotely or via a switch that lets the door open and close when required because a garage door is too heavy to move by hand. This is called a smart garage door opener.

A garage door opener also works as a door lock. When people started using horses with carriage they felt the necessity to store their vehicles along with horses. So they started building an outbuilding where they could store their carriage and horses. But due to the smell of horses, they separated the carriage section and made an outbuilding only for their carriages. To keep the carriages safe from rain or snow, they felt the necessity to build a door for the building.

During the old days, these doors were very simple barn double doors that opened outward and were supported by hinges and screws. But due to daily use, the doors easily got worn down and did not last long. Also during snow, the doors could not be moved until the snow was removed.

Then came the idea of a sliding track for doors. This idea did not last long as for a sliding door the garage had to have a huge width. Then people made a door that can be folded which was a better idea as it took less space and did not require to increase the width of the garage building. As technology improved, in 1921 C.C Johnson first came up with an idea and built the first garage door that could be folded horizontally towards the ceiling and required no extra space.

These garage doors were made from wood and were heavy to lift. As a result in 1925 Johnson also invented the garage door opener which, removed the problem of lifting heavy garage doors.

Since then garage door opener became a mandatory part for any garage and kept developing. But till 1993, many accidents occurred where children were injured or killed by the garage door due to no safety protocol incorporated with the door opener. Due to these occurrences, the consumer product safety commission of USA made it mandatory to install sensors to the garage door opening system so if anything was to be under the door while it was closing it would reverse itself so that no accident occurs. Now any such accidents have become very rare.

Today we will discuss how do garage door openers work.

Working process of garage door opener:

A garage door opener system consists of several parts. The driving part is the electrical controlling unit which is connected to some mechanical parts. The main part of this system is the garage door. The garage door is connected to the modern garage door openers system through the following components or parts:

Electrical unit:

The electrical unit is the part that gives the door the power to slide up and down. This unit consists of an electric motor most of the time half horsepower along with some gear to control the doors opening and closing motion.

T-rail is the part that gives protection and guidance to the chain, screw, or belt drive whatever operating option is chosen by the user.

It also has a height adjustment sensor which helps the user how far the door should go up or down. It can also be used to adjust the height between the garage door and the floor.

An inverter and battery are incorporated in this unit. The inverter transforms AC to DC to operate the whole electric unit. It also keeps the battery charged when there is no power, and the battery can work as a power source.

Mechanical unit:

Now for the mechanical parts, we have the following components:

The roller is situated on both sides of the garage door which helps the door to slide easily and without any noise.

There are three tracks in a garage door system. Two are at both ends, and one is at the midsection. These are tracks using which the door glides up and down.

The opener system can have a chain, screw, or belt which helps to move the trolly smoothly. The chain drive system is quite outdated and makes a lot of noise. The screw and belt system is new, and they operate very quietly. They are also more expensive than the chain system.

There is a curved door arm that is connected with the chain or belt. When the chain or belt moves so, does the arm along with the door attached to it.

Another important part is the torsion spring. It is important because it helps to control the door’s motion while it slides up or down.

The torsion spring is connected to cables and drums situated at both ends of the door. This helps the torsion spring by winding and unwinding in a controlled way which in terms lets the torsion spring control the motion of the door.

Safety and emergency:

The safety of the door opening system is controlled by a safety automatic garage door sensor connected near the door. It starts working when something or someone gets in the way of the door while it is closing. If it senses so, it will halt or reverse back to avoid any unwanted situation.

If the electrical system fails to work then there is an emergency lever that can be found connected to the mid-track section. The user can manually open or close the door using this lever.

Main working theme:

Now how does this work? This electrical door opening system is built using radio transmission technology. As we all know, the opener takes command from a garage door switch or garage door remote control, or garage door opener remote. It is the frequency that helps the remote and control box to sync. The control box and remote have the same frequency so, when it gets the signal it starts operating. It also has a safety measure. It changes the signal code every time the user presses the button or remote. In its memory, it has these codes saved. So if the code does not match it will not work.


Nowadays, as technology is advancing the garage door opening system is also improving. There are so many electrical garage door openers in the market. But to buy one you need to know the working principle of these devices or systems. This article will hopefully make it easy for you to understand the basics of how do garage door openers work. 

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