In recent years, as long as you talk about harmonic reducers, people in the industry who are engaged in industrial robots are not unfamiliar. In the past many years, this core robot component, which was sometimes oversized, had occupied the overall cost of about 30% of robots due to the long-term monopolization of core technology by foreign brands. This reality also objectively pushes up the cost of domestic robot applications…

Harmonic reducer past and present:

In the mid-1950s, with the development of global science and technology, American Mather invented a new type of harmonic transmission technology based on the principle of elastic deformation of thin shells using the principle of flexibility and elasticity of metal. Harmonic drive technology is mainly used in aerospace, industrial robots, precision equipment, radar communications equipment, printing machinery, textile machinery, semiconductor industry wafer transfer device, printing and packaging machinery, medical equipment, metal forming machinery, instrumentation, optical manufacturing Instruments, nuclear facilities and aerodynamic experimental research and other fields.

The emergence of this new type of harmonic drive has attracted the attention of countries. Introduced to Japan in 1970, Japan’s Harmonic Drive Systems Inc. (HDSI), Japan’s first overall motion control leader, was born. The HarmonicDrive harmonic reducer produced by Japan’s HDSI Co., Ltd. is characterized by its lightweight, small size, high transmission efficiency, wide deceleration range, and high precision, and is widely used in various transmission systems. HDSI mainly produces and sells various precision deceleration devices, making it a leader in overall motion control. In order to cover the area of low reduction ratios that cannot be covered by harmonic retarders, HDSI products have also developed Harmonic Planetary, a precision planetary gearbox. The unique internal ring gear deformation process enables the planetary gears to mesh tighter and eliminate backlash, thus controlling the transmission error within a precise range. HDSI was initially developed only in its own country. There are companies with long-term cooperation such as Yaskawa Electric, Mitsubishi Electric and Fanuc.

In recent years, China’s industrial robotics industry has entered a new period of historical opportunities. International robot companies represented by ABB, KUKA, Yaskawa, and Fanuc have entered China in large numbers and set up factories to seize market share. In China, such as mobile phone manufacturing, semiconductors, liquid crystal production machinery and other industries, the demand for small robots is also growing. However, for domestic industrial robots, especially harmonic reducers, servo motors, control systems, etc. Heavy dependence on imports has led to a gap between its competitiveness and foreign companies, but these are also the upstream components and key components of industrial robots. According to the statistics of the International Robot Federation (IFR), in 2012, China imported a total of about 22,000 industrial robots, and China will be the fastest growing industrial robot market in the world. HDSI’s harmonic reducer is an irreplaceable component for small industrial robots (below 20kg) or articulated arms, which brings new opportunities for expanding the Chinese mainland market. In January 2011, HDSI established in China to establish Hamernaco (Shanghai) Trading Co., Ltd., which is a wholly-owned sales subsidiary established in China for its investment in China. It is mainly responsible for technical support and after-sales services such as sales and selection of HDSI products in mainland China.

The harmonic reducer consists of only 3 basic components: the flexspline, the wave generator and the rigid wheel. The outer diameter of the flexspline is slightly smaller than the inner diameter of the rigid wheel, and usually the flexo wheel has 2 teeth less than the rigid wheel. The elliptical shape of the wave generator determines that the contact points of the teeth of the flexspline and the rigid wheel are distributed on two opposite sides of the center of the ellipse. During the rotation of the wave generator, the contact portion of the flex spline and the just-toothed tooth start to mesh. When the wave generator rotates by 180° every clockwise, the flexspline is equivalent to the one-tooth number difference of the counterclockwise rotation of the rigid wheel. In two places with 180° symmetry, more than 30% of all teeth are meshed at the same time, which also results in high torque transmission.

After the birth and development of the harmonic reducer, we will analyze the special bearings for harmonic reducer.

Precision bearings are important and key basic components in the equipment manufacturing industry. They directly affect the performance, quality and reliability of major equipment and host products, and are known as the “heart” components of equipment manufacturing. Industrial robot harmonic reducer, its supporting bearing precision, friction torque, rigidity directly affect the stability of the entire harmonic reducer and even the robot and safe operation. The robot supporting bearing is a market segment for bearing applications and is an emerging market developed with the rise of the industrial robot industry. Precision bearings for robots mainly include: harmonic reducer bearings, flexible bearings, RV reducer bearings, cross roller bearings, thin-wall bearings and other cross-section.