The hollow rotary platform operates on the principle of a precision planetary reducer. Planetary gears revolve around the sun gear, achieving high-precision rotary transmission through a clever combination of motions, typically with a transmission efficiency of 90%-95%.
It utilizes the principle of harmonic drive, relying on the interaction of flexible wheels, rigid wheels, and a wave generator to achieve high-ratio and high-precision rotation. In some precision equipment, positioning accuracy can reach ±30 arcsec. Magnetic coupling is also applied in hollow rotary platforms, using magnetic force to achieve non-contact power transmission. This makes the platform run more smoothly and effectively avoids mechanical wear, extending the equipment's lifespan. In motor-driven hollow rotary platforms, the rotational motion output by the motor is transmitted via a belt or chain drive mechanism, coupled with high-precision bearing support, ensuring stable rotation at the set speed with minimal linear velocity deviation. When using a worm gear drive principle, the special tooth profile design of the worm gear provides a large reduction ratio, typically 10-80, effectively reducing speed and increasing torque.
Based on the encoder feedback principle, the hollow rotary platform is equipped with a high-precision encoder to monitor the rotation angle in real time and feed the signal back to the control system, achieving precise angle control with an angle resolution of up to 0.01°. The hollow rotary platform using the hydraulic drive principle delivers high-pressure oil to the hydraulic cylinder via a hydraulic pump, driving the piston and thus rotating the platform. Its output torque can be flexibly adjusted according to the hydraulic system pressure. Air bearings are used in some hollow rotary platforms, supporting the platform through an air cushion formed by gas, greatly reducing friction and allowing the platform to operate with an extremely low coefficient of friction, such as as low as 0.001-0.005. Some hollow rotary platforms utilize a precision ball screw drive principle, converting the rotational motion of the motor into linear motion, and then into platform rotation through a specific mechanism, achieving a positioning accuracy of ±0.05mm.
