In the field of mechanical transmission, the speed reducer is an intermediate device between the power source and the actuator. Usually, the high-speed power of the motor, the internal combustion engine and the like are transmitted through the pinion gear on the input shaft to mesh the large gear on the output shaft to achieve the purpose of deceleration. And pass more torque. The currently proven and standardized reducers are: spur gear reducers, turbine reducers, planetary reducers, planetary gear reducers, RV reducers, cycloidal pin reducers and harmonic reducers. Since the 1980s and 1990s, in the development of emerging industries such as aerospace, robotics and medical devices, high-performance precision reducers with simple and compact structure, high transmission power, low noise and stable transmission are needed, among which RV reducer is harmonious. Wave reducers are two important reducers in precision reducers.
RV (Rot-Vector) reducer
The RV reducer was developed on the basis of a cycloidal pinion transmission with a two-stage deceleration and a central disc support structure. Since it was put into the market in 1986, it has been the “master” reducer for robots due to its large transmission ratio, high transmission efficiency, high motion accuracy, low backlash, low vibration, high rigidity and high reliability.
The harmonic reducer consists of three parts: the harmonic generator, the flexibility theory and the rigid wheel. The working principle is that the harmonic generator produces a controllable elastic deformation of the flexible wheel, and the flexible wheel and the rigid wheel mesh to transmit the power. And achieve the purpose of deceleration; according to the wave generator, there are cam type, roller type and eccentric disc type. The harmonic reducer has a large transmission ratio, a small profile, a small number of parts and a high transmission efficiency. The single-machine transmission ratio can reach 50-4000, and the transmission efficiency is as high as 92%-96%.
Planets, as the name suggests, are planetary reducers that have three planetary wheels that rotate around a sun gear. The planetary reducer is small in size, light in weight, high in load carrying capacity, long in service life, stable in operation and low in noise. It has the characteristics of power splitting and multi-tooth meshing. It is a versatile industrial product with comparable performance to other military grade planetary reducer products, but it has the price of industrial grade products and is used in a wide range of industrial applications. .
The presence of a precision reducer allows the servo motor to operate at a suitable speed and accurately reduce the speed to the speed required by various parts of the industrial robot, increasing the rigidity of the machine while outputting greater torque. Compared with universal reducers, robotic joint reducers require short drive chains, small size, high power, light weight and easy control. There are two main types of reducers that are widely used on articulated robots: RV reducers and harmonic reducers.