How a Chain Drive Garage Door Opener Works

A chain drive garage door opener is one of the options to choose from in an automatic door-opening system. These systems that power your garage door come in two types: shaft drive and trolley systems. The chain drive in one of three varieties of trolley systems; the other two are belt drives and screw drives. A chain drive opener differs in several ways in terms of engineering, cost, and even how much noise it makes.

Lifting and Lowering Power

As its name suggests, the chain drive opener uses a chain running along a rail to operate the electric motor that lifts and lowers the door. Your garage door is actually controlled by a system of counterbalance springs and cables that determine how much force to exert, and the motor only controls how far the door opens or closes. In a trolley system, the trolley is connected to an arm that is attached to the top of the garage door. This arm slides back and forth to control the door movement, and the chain drive is one of the mechanisms that makes this possible.

Chain Drive Movement

The chain that drives your garage door is installed as part of an assembly unit attached to a system of tension springs, all powered by an electric motor that receives a signal from your garage door opener. The chain, in this case, is needed to guide the trolley in the right direction to operate the door. The chain drive is connected to a system of rollers, gears, and pins that are balanced to open and close the door smoothly over and over. One advantage of a chain drive is that it follows the same basic principles as a pulley system; therefore it can still be manually operated if there is a power outage or other emergency. 

The chain drive garage door opener system is attached to the power unit towards the back of the garage. The chain is fitted around the drive sprocket on the motor that is powered by electricity to move both the trolley and door back and forth. The chain loops around an idler sprocket at the opposite end of the main drive track, and this completed circle allows the electric motor to turn the chain and cause the trolley to lift the door. The chains used in chain drives are the least expensive out of the three types of trolley systems, and they can be the longest-lasting, once a few common problems with them are addressed.

Chain Maintenance

Some home owners report the chain in a chain drive opener can gradually loosen. This can create problems with how smoothly the door operates and can even cause it to get stuck or dangerously come down too fast. Periodic inspections of your chain drive system will do much to prevent these problems. Many agree that a drawback to chain drive opener systems is the amount of noise they make; they are quite loud every time the door is operated compared to others such as the belt system. However, there is an agreement this is worth tolerating for the economical price and long life of the chain if it is kept in good condition.