Harmonic drive is the use of a controlled elastic deformation of a structure to achieve the transmission of mechanical motion. Harmonic drive usually consists of three basic components, including a rigid wheel with internal teeth, a flexible wheel with radial elastic deformation and external teeth that can be radially deformed during operation, and an elliptical, externally mounted flexible wheel. Ring wave generator with flexible rolling bearings.
The number of external teeth of the flexible wheel is less than the number of internal teeth of the rigid wheel. When the wave generator rotates, the outer teeth of the flexible wheel corresponding to the direction of the long axis are exactly meshed with the inner teeth of the rigid wheel; in the direction of the short axis, the outer teeth are completely separated from the inner teeth.
When the rigid wheel is fixed and the wave generator rotates, the outer teeth of the flex wheel will mesh into and out of the inner teeth of the rigid wheel in turn, and the radial displacement of any point on the flex wheel ring gear will change approximately to a sinusoidal waveform , so this kind of drive is called harmonic drive. Harmonic drive is the use of a controlled elastic deformation of a structure to achieve the transmission of mechanical motion.
In the printing and packaging equipment, there is a key component - the phase adjustment mechanism, which is directly related to the quality and production efficiency of the printing and packaging products. Harmonic drive gear reducer can be well applied in phase adjustment mechanism
Compared with the rigid transmission in the traditional printing and packaging machinery, the harmonic transmission is more widely used in the modern printing and packaging production, mainly because it has the following 8 advantages, which can be applied to the printing and packaging of the industrialized production, and realize high speed, precision and long time. effective operation.
First, the transmission ratio is large. The single-stage transmission ratio can be as high as 107 if the internal meshing complex wave transmission is used. The general single-stage transmission ratio can also hinder the internal change between 1.002 and 300, which can meet the general transmission requirements of printing machinery.
Second, the number of meshing teeth is large at the same time. There are eight combinations of harmonic transmission, so appropriate meshing parameters can be selected, and special tooth profiles and different radial coefficients of cross-sections can be used to form an involute three-maintenance tooth profile. Then the number of meshing teeth can be increased to 30% to 50%, effectively increasing the meshing area.
Third, the mechanism is simple and light in weight. Under the same working conditions, bearing capacity and reduction ratio, the number of parts and weight of the harmonic drive reducer is significantly lower than that of the traditional rigid drive reducer, and it can be installed and installed with the increase of the transmission ratio. operate.
Fourth, the bearing capacity is large and the efficiency is high. Different from other transmissions, the harmonic drive uses multi-tooth meshing, and there are "staggered teeth", so its bearing capacity is larger, and the transmission energy generated by "misalignment" is also more stable and efficient.
Fifth, the transmission precision is high. The multi-regional and multi-tooth meshing characteristics of harmonic transmission can achieve higher transmission precision under the same manufacturing precision.
Sixth, the tooth side clearance is small, and the meshing parameters and structural parameters of the harmonic drive can be freely selected, so as long as the reasonable parameters are selected, the gap can be matched and the gap can be avoided to have a great influence on the harmonic drive.
Seventh, the meshing is surface contact and multi-tooth meshing, so the sliding speed is small and the wear is less, so the transmission is more stable, the noise is less and there is no impact phenomenon.
Eighth, it can realize the transfer movement of the sealed space. The sealed space is an important environment for the automatic production of printing and packaging at this stage. The sealed space is to reduce the influence of air and other impurities on the coloring of printing and packaging and the effect of printing faceplates. Therefore, when automatic production is realized Turn the environment into a seal.
The harmonic drive can fix the flexible wheel in the two sealed media, so that the movement between the seals can be transmitted, and the valve of the high temperature and high pressure pipeline can also be manipulated. This is also the most unique advantage of the harmonic drive, which meets the needs of modern printing and packaging machinery. production requirements and job requirements.
