Electric telescopic doors are widely used in residential communities, industrial parks, and school campuses. The door panel extends and retracts along a ground track, operated by a remote control. This article explains the basic structure and working principle of such doors.
1. Door Panel Structure
The door panel consists of multiple metal sections connected by hinges. Each section contains a steel or aluminum alloy frame for structural support. Adjacent sections can fold together, allowing the entire door to compress tightly when retracted and form a complete barrier when extended. Wheels at the bottom of each section fit into track grooves, ensuring smooth operation without derailment.
2. Drive System
The drive system consists of motor, reducer, and transmission chain. The motor outputs rotational power, which the reducer amplifies into higher torque before transmitting to the bottom drive wheels via the chain. The drive wheels interact with the track to push the door forward for opening or backward for closing. This chain drive solution offers mature technology, good parts availability, and easy maintenance, making it the current market mainstream.
3. Extension and Retraction Principle
When opening, the motor drives the drive wheels to move forward along the track. Each panel section unfolds sequentially at the hinges until the entire barrier is formed. When closing, the motor reverses, and the panels fold from the end, stacking compactly beside the drive unit. More sections provide wider coverage; common configurations range from 6 to 12 sections to meet various opening width requirements.
4. Control System
Control options include remote control, password keypad, card swipe, and mobile APP. The controller detects door position through limit switches or encoders, automatically cutting power when the door reaches its set endpoint to prevent collision damage. Some products support integration with access control systems for card-based or remote opening.
5. Important Considerations
Ground track installation requires a flat base. The folding joints have limited sealing performance, and chains require regular tension checks during long-term use. In windy areas, reinforced structures and wind-resistant tracks should be selected for safe operation.
This article compiles information from publicly available automatic door industry resources.