Electric telescopic doors originally chose AC induction motors, but more and more manufacturers choose low-voltage brushed DC motors with gearboxes to replace AC induction motors. The main advantages and considerations are as follows:
1. High starting torque and load adaptability
DC motor characteristics: Brushed DC motors can provide high instantaneous torque at startup, which is especially suitable for scenarios where electric telescopic doors need to start and stop frequently and overcome static friction.
Gearbox torque increase: The gearbox can further amplify the torque to adapt to different door weights (such as large park metal doors), while reducing the motor speed to a practical range to avoid insufficient power caused by direct drive.
2. Cost control and cost-effectiveness
Low motor cost: The brushed DC motor + gearbox has a simple structure, and the procurement cost is significantly lower than that of the AC induction motor.
Eliminate the inverter: AC motors need to be equipped with inverters to achieve speed regulation, while DC motors only need a simple PWM speed regulation circuit, and the overall system cost is lower.
Maintenance cost trade-off: Optional carbon brushes need to be replaced regularly, and under low voltage, the working life of brushed motors is also long; although electric doors are used frequently, the working time is usually low, the maintenance cycle is long, and the overall cost is still advantageous.
3. Safety of low-voltage power supply
Safe voltage (12/24V): Low-voltage DC motors meet the safety standards for outdoor equipment, reduce the risk of electric shock, and are especially suitable for outdoor humid environments or public areas.
Simplified power supply design: It can be directly powered by batteries or adapters without complex step-down or isolation circuits, which is suitable for power failure emergency operations (such as backup batteries).
4. Control flexibility and response speed
Convenient speed regulation: The speed can be linearly controlled by adjusting the voltage or PWM duty cycle, which is convenient for the door body to start and stop slowly and improve the user experience.
Fast start-stop response: The DC motor has small inertia and fast start-stop response, which is suitable for scenes requiring precise position control (such as infrared induction anti-pinch).
5. Space and installation optimization
Compact structure: The DC motor + gearbox is small and easy to integrate into the limited space inside the telescopic door.
Simplified transmission: The gearbox can directly output the appropriate speed, reduce additional transmission components such as belts and chains, and reduce installation complexity.
6. Adaptability to specific scenarios
Power failure emergency: The low-voltage system can seamlessly switch to the backup battery to ensure the normal opening and closing of the door during a power outage.
Environmental compatibility: In areas with unstable voltage, low-voltage DC systems are more tolerant to fluctuations than AC motors.
Potential trade-offs and solutions
Carbon brush life: High-quality graphite carbon brushes or modular design are used for quick replacement. Moreover, in the low-voltage power supply environment itself, the working life of the brushed motor is very long.
Noise control: Optimize the gearbox tooth shape (such as helical teeth) and lubrication to reduce operating noise.
Waterproof design: The motor and gearbox are encapsulated with a protection level of IP54 or above, which is suitable for outdoor environments.
Summary
The combination of low-voltage brushed DC motor + gearbox is more suitable for the medium-low load and intermittent operation requirements of electric telescopic doors in terms of cost, safety, and control flexibility, while AC induction motors are more suitable for industrial-grade high-load continuous operation scenarios. Honlite Electromechanical recommends the D53+G DC brushed motor with eccentric gearbox solution, which is a typical optimization solution after weighing customer demand performance, budget cost, and usage environment.
Telephone: 0769-86637398- 223
Phone: 86-13450675746
WeChat: 86-13450675746
Fax: 0769-86638487
E-mail:watson@honlite.com.cn
Address: Xin wei li canton, Liu wu Industrial Area, She kit town, Dongguan city, Guangdong province,China
