RV reducer, structural characteristics, working principle and design calculation

Release Time：

2025-02-26

RV reducer is a high-precision and high rigidity precision reduction device widely used in industrial robots, CNC machine tools and other fields. The following provides a detailed explanation from three dimensions: structural characteristics, working principles, and design calculation analysis:

RV reducer, structural characteristics, working principle and design calculation
RV reducer is a high-precision and high rigidity precision reduction device widely used in industrial robots, CNC machine tools and other fields. The following provides a detailed explanation from three dimensions: structural characteristics, working principles, and design calculation analysis:

1、 Structural characteristics

1. Dual stage deceleration structure

Grade: Planetary gear transmission

Composed of sun gear, planetary gear, and ring gear, it achieves initial deceleration (usually 3-10 times the speed ratio).

Second stage: Cycloid pinwheel transmission

By driving the cycloidal gear with an eccentric shaft and meshing with the needle teeth, a secondary reduction is achieved (with a speed ratio of up to 30-100 times).

2. Core components

Cycloid Disk: It adopts a cycloidal tooth profile and meshes with needle teeth to achieve high-precision transmission.

Needle Bearing Ring: Fixing the needle teeth to form a rigid support.

Crankshaft: Connecting planetary gears and cycloid gears, transmitting power and achieving eccentric motion.

Output Flange: integrates cycloidal wheel motion and outputs torque.

2、 Working principle

1. Power transmission path

Input shaft → planetary gear reduction → eccentric motion of crankshaft → cycloidal gear revolution+rotation → needle tooth constraint → output disc rotation.

2. Kinematic process

Eccentric rotation of crankshaft: The planetary gear drives the crankshaft, causing the cycloidal gear to undergo eccentric revolution.

Cycloid gear meshing: Cycloid gear teeth periodically mesh with needle teeth, and are constrained by the needle tooth shell to produce reverse rotation.

Output synthesis: The rotation of the cycloid wheel is transmitted to the output disc through the crankshaft pin, forming a deceleration output.

3、 Applications and Trends

Typical scenarios: Industrial robot joints (accounting for 15%~30% of the cost), precision turntables, aerospace agencies.

Technological trends: lightweight (aluminum alloy shell), integrated (built-in encoder), low noise (topology optimized tooth profile).