Planetary gear reducers are a type of precision geared motor, characterized by high efficiency and versatility. Based on power, planetary gear reducers are categorized into small planetary gear reducers and high-power planetary gear reducers, each applied to different fields and scenarios. The following section details the structure and working principle of planetary gear reducers.
I. Structure and Composition of Planetary Gear Reducers
The structure of a planetary gear reducer mainly consists of planetary gears, a sun gear, an internal gear ring, a planetary carrier, and a drive source (motor).
II. Working Principle of Planetary Gear Reducer
1. Number of stages: The number of sets of planetary gears. Since one set of planetary gears cannot meet a large transmission ratio, sometimes two or three sets are needed to meet the user's requirements for a larger transmission ratio . Due to the increased number of planetary gears, the length of a 2-stage or 3-stage reducer will increase, and the efficiency will decrease.
2. Backlash: With the output end fixed, the input end is rotated clockwise and counterclockwise until the input end generates the rated torque ±2% of the torque. At this point, the input end of the reducer will have a slight angular displacement. This angular displacement is the backlash .
3. The planetary gear reducer consists of an internal gear ring (A) tightly coupled to the gearbox housing. At the center of the ring gear is a sun gear (B) driven by external power. Between the two is a set of planetary gears (C) consisting of three gears equally distributed on a tray. This set of planetary gears floats in the middle supported by the output shaft, the internal gear ring, and the sun gear. When the input power drives the sun gear, it can drive the planetary gears to rotate and revolve around the center along the trajectory of the internal gear ring. The rotation of the planets drives the output shaft connected to the tray to output power.
