RV Reducer

The input part includes the input shaft and planetary gear mechanism.

The motor transmits power to the sun gear through the input shaft, which meshes with multiple planetary gears. The planetary gears simultaneously revolve around the sun gear and rotate on their own, completing a first stage reduction. This step can initially reduce the speed and increase the torque, providing stable power input for the subsequent cycloidal transmission.

The deceleration transmission part is the core of the RV reducer, consisting of an eccentric shaft, a cycloidal wheel, and a pin wheel.

The rotation of planetary gears is transmitted to cycloid gears through eccentric shafts, and each eccentric shaft drives two cycloid gears with a phase difference of 180 ° to perform eccentric motion. The tooth profile of the cycloid wheel is a special cycloid curve, which forms a multi tooth meshing with a needle wheel (composed of several evenly distributed needle teeth) fixed on the housing. During the motion, the number of teeth simultaneously meshing between the cycloid wheel and the needle wheel can reach more than 2/3 of the total number of teeth. This multi tooth load sharing design is the key to its high rigidity.

The output part achieves power output through the output flange and crankshaft

The eccentric motion of the cycloidal gear is converted into the rotational motion of the output flange through the bearings on the crankshaft, and ultimately transmits the power that has undergone two-stage deceleration to the load end. Throughout the entire transmission process, power is transmitted layer by layer through gear meshing, achieving a large reduction ratio (usually 10-100:1) and offsetting the centrifugal force generated by eccentric motion through a symmetrical structure, ensuring smooth operation.

High rigidity is its most significant advantage.

The multi tooth meshing design distributes the load to multiple tooth surfaces, combined with high-strength alloy materials (such as carburizing and quenching steel) and precision machining, allowing the RV reducer to withstand huge radial and axial loads, maintaining structural stability and minimal deformation during high-speed robot movement and emergency stop.

Low return error is the core guarantee for achieving precise positioning.

Return error refers to the hysteresis of the output shaft during reverse motion. The RV reducer controls this error at an extremely low level through precise gear profile modification, bearing pre tightening, and zero clearance assembly, ensuring that the robot's repeated positioning accuracy can reach within ± 0.01mm.

High torque density and compact structure form a perfect balance.

Under the same volume, the output torque of RV reducer is 1.5-2 times that of ordinary planetary reducer. This "small body, large energy" characteristic enables it to meet the needs of space limited scenarios such as robot joints, while reducing the overall weight of the equipment.

In addition,

RV reducers have the advantages of long lifespan (with an average time between failures of over 10000 hours), smooth operation (with extremely low vibration and noise), and strong impact resistance, making them difficult to replace in the high-end equipment field.

RV-E Series:

Main Bearing Built-in Type Cycloidal Gearboxes

RV-SE Series:

Input Flange Type Cycloidal Gearboxes

RV-C Series:

Hollow Type Cycloidal Gearboxes

RV-SC Series:

Input Flange Hollow Type Cycloidal Gearboxes

RV-N Series:
Output Shaft Cycloidal Gearboxes

Harmonic reducers

RV reducers have higher rigidity, stronger impact resistance, and no fatigue problem of flexible wheels in harmonic reducers. Their service life can reach 3-5 times that of harmonic reducers. Although harmonic reducers have a slight advantage in miniaturization, RV reducers are still the preferred choice for robot joint parts that require high torque and high reliability.

Traditional planetary reducers

the return error of RV reducers has been reduced by more than 80%, and the multi tooth meshing design has increased its rigidity by more than 30%. Although planetary reducers have lower costs, they are prone to tooth wear and decreased accuracy under high-speed and heavy loads, which cannot meet the long-term precision operation requirements of high-end equipment.

Perspective of application scenarios

RV reducers are suitable for situations that require extremely high rigidity, accuracy, and lifespan. Harmonic reducers are mostly used in light load high-precision scenarios, while planetary reducers are widely used in the mid to low end transmission field. The three complement each other but cannot be completely replaced.

Application of RV reducers has expanded from industrial robots to multiple high-end equipment fields

in the field of industrial robots, it is the core component of six axis robots, collaborative robots, SCARA robots, etc., responsible for joint rotation and load drive functions; In the field of precision machine tools, it is used for key components such as CNC turntables and servo tool holders to ensure machining accuracy; In the aerospace field, it is applied to satellite antenna drive, radar steering mechanism, etc., and can withstand extreme environmental tests; In the field of medical equipment, it is used for surgical robots and precision detectors to achieve sub millimeter level operations; In the field of new energy, it is used for wind power variable pitch systems and photovoltaic tracking devices to improve energy conversion efficiency.

At the industrial level

technological breakthroughs in RV reducers have significant strategic importance. For a long time, this technology has been monopolized by Japanese companies such as Hamonaco and Sumitomo, and China has been highly dependent on imports. In recent years, with the breakthroughs in research and development by domestic enterprises, the performance of domestically produced RV reducers has been continuously improved. This not only breaks the foreign monopoly, but also promotes the independent and controllable development of China's robotics industry, reducing the manufacturing cost of high-end equipment.