The entire transmission system of the harmonic drive reducer can be divided into three parts: the input section, the reduction section, and the output section.
Installation steps:
1. Check whether the two cycloidal wheels constitute a matched pair. Cycloidal wheels are manufactured in pairs—this means that during production, the two pieces of a cycloidal wheel are never separated. When installing, the concept of a “matched pair” refers to the two cycloidal wheels being perfectly aligned with each other. Specifically, the bearing holes, ten-hole (pivot pin holes), and external tooth profiles must all coincide exactly. Viewed from the front, they should appear as a single unit. If they align perfectly, then they are indeed a matched pair; if they don’t align, then they’re not a matched pair and cannot be used. Note that cycloidal wheels have a distinct front and back side, and each wheel is marked accordingly. Moreover, the markings on each matched pair of cycloidal wheels are unique and different from one another.
2. Rotate one of the cycloidal gear plates by 180°—that is, when the middle bearing holes completely align, the external tooth profiles will be precisely offset, and the root positions of the teeth on the upper plate will exactly coincide with the tip positions of the teeth on the lower plate. Note that you must carefully remember the relative positions of these two plates; mark them yourself or recall the original positions of any existing markings on the plates. (This applies to single-tooth-difference cycloidal gears; for double-tooth-difference gears, a 180° rotation is not required.)
3. Place a cycloidal gear into the needle gear housing, then manually rotate it to check whether it turns smoothly and whether there is any wobbling.
4. Insert the eccentric bearing. Since the bearing bore of the harmonic drive reducer is equivalent to the outer race of the eccentric bearing, the correct position of the eccentric bearing is such that the bearing bore of the lower cycloidal gear precisely and completely accommodates the cylindrical rollers of the eccentric bearing.
5. Insert the spacer ring.
6. Next, insert another cycloidal gear. Placing this gear is crucial—make sure to position it precisely according to the markings you’ve drawn.
7. Place the shaft sleeve on and use your hand to rotate it, checking whether it turns smoothly and verifying that the installation is correct.