REV FIRST Global, Руководство по эксплуатации

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FIRST Global Building Guide Created by REV Robotics 2019, Licensed Under CC BY-SA 25
3.8.3 5mm Hex Shaft
The REV Robotics building system is constructed around a 5mm hex shaft. Using a hex shaft to transmit torque in the
system removes the need for set screws, which can loosen over time and can damage shafts. Hex Shafts are precision
ground 5mm stainless steel and fits snuggly in all hex drive motion components (Figure 41).
Figure 41: Stainless Steel 5mm Hex
REV Robotics Hex Shafts come in three lengths, 75mm (REV-41-1347), 135mm (REV-41-1347) and 400mm (REV-41-
1362). For high load applications, it is recommended to either stack multiple gears or sprockets in parallel, or use the
metal hex hub adaptor (REV-41-1362) to increase strength.
3.8.4 Shaft Collars and Spacers
Shaft collars are used to prevent lateral (sideways/sliding) movement of a shaft, or a part on the shaft. A shaft collar is a
hollow cylinder with one more set screws which tighten towards its center and an inner dimension (ID) that is just slightly
larger than the shaft it is being used on (Figure 42). Since shaft collars are used to prevent lateral shaft movement they
are often used in place of shaft spacers.
Figure 42: 6mm Shaft Collar
To use the shaft collar, slide it onto the hex shaft and rotate it until a flat side is facing the setscrew (Figure 43). Adjust the
collar to the desired location and use a 1.5mm Allen wrench to tighten the included set screw snuggly against the shaft. A
small amount of a thread locker product, like Loctite Blue, can be used if desired.
Figure 43: Shaft Collar Tightened on a Hex Shaft
The REV Robotics shaft collar has a 6mm inside diameter and is customized with a M3 thread so a standard hex cap bolt
can be used instead of the supplied set screw (Figure 44).