The difference between RV reducer and harmonic reducer

RV reducers are generally used for industrial robots with heavy loads, and harmonic reducers are mainly used for industrial robots with small loads. Nabtesco and Murata are representatives of RV reducers, and harmonic reducers are basically monopolized by Japanese Hamonaco harmonic reducers. Harmonic reducer is a kind of harmonic drive device, which includes harmonic accelerator and harmonic reducer.  Harmonic reducer mainly includes: rigid wheel, flexible wheel and wave generator, all of which are indispensable. Among them, the number of teeth of the rigid wheel is slightly larger than the number of teeth of the flexible wheel. The length of the wave generator is larger than the diameter of the inner circle of the undeformed flexspline: when the wave generator is installed in the inner circle of the flexspline, the flexspline is forced to produce elastic deformation and become elliptical, so that the flexspline teeth at the long axis are inserted rigidly. In the tooth groove of the wheel, it becomes a fully meshed state; and the teeth of the two wheels at the short axis are not in contact at all and are in a disengaged state. During the process from meshing to disengagement, it is in the state of meshing out or meshing in. When the wave generator rotates continuously: the flexspline is forced to continuously deform, so that the teeth of the two wheels continuously change their working states during the process of meshing, meshing, meshing, and disengagement, resulting in the so-called staggered tooth movement. In this way, the motion transmission between the active wave generator and the flexspline is realized. RV transmission is a new type of transmission. It is developed on the basis of traditional pin-vibration planetary transmission. It not only overcomes the shortcomings of general pin-vibration transmission, but also because of its small size, light weight, large transmission ratio range, and longevity. It has a series of advantages such as long, stable accuracy, high efficiency, stable transmission and so on. The RV reducer is composed of a cycloidal pin wheel and a planetary support. With its small size, strong impact resistance, large torque, high positioning accuracy, low vibration, large reduction ratio and many other advantages, it is widely used in industrial robots, machine tools, and medical testing. Equipment, satellite receiving system and other fields. Compared with the harmonic drive commonly used in robots, it has much higher fatigue strength, stiffness and life, and the accuracy of the return difference is stable. Unlike the harmonic drive, the motion accuracy will be significantly reduced as the use time increases. Most precision robot transmissions use RV reducers. Therefore, this kind of RV reducers has a trend of gradually replacing harmonic reducers in advanced robot transmissions.