C4 Maintenance 8. Joint #4
C Series Maintenance Manual Rev.2 109
8.2 Joint #4 - Replacing the Reduction Gear Unit
A reduction gear unit consists of the waveform generator, flexspline, and circular spline. When replacing the
reduction gear unit, be sure to replace these parts all together as a set.
For details, refer to C4 Maintenance: 17. C4 Maintenance Parts List.
It is recommended replacing the O-rings (for Joint #4) when replacing the reduction gear unit.
Maintenance
Joint #4 reduction gear unit
Tools
Hexagonal
wrench
width across flats: 1.5 mm
For M3 hexagon socket set screws
width across flats: 2.5 mm
For M3 hexagon socket head cap bolts
For M4 hexagon socket head cap bolts
For belt tension adjustment
Removal: Joint #4 Reduction gear unit
1. Remove the Joint #4 motor unit from the Arm #3.
For details, refer to C4 Maintenance: 8.1 Joint #4 – Replacing the Motor, Installation steps (1) through
(5).
2. Remove the Joint #5 motor unit from the Arm #4.
For details, refer to C4 Maintenance: 9.1 Joint #5 – Replacing the Motor, Installation steps (2) through
(5).
3. Remove the Joint #6 motor unit from the Arm #4.
For details, refer toC4 Maintenance: 10.1 Joint #6 – Replacing the Motor, Installation steps (3) through
(5).
4. Remove the cable unit of the Arm #4.
For details, refer to C4 Maintenance: 4.1 Replacing the Cable Unit, Installation steps (9) through (20).
5. Remove the Arm #4 cable fixing plate.
Hexagon socket head cap bolts: 2-M4×8
6. Remove the Joint #4 timing belt.
7. Remove the Joint #4 fitting.
8. Remove the LED lamp.
Joint #4 fittings
LED lamp
Joint #4 cable fixing plate
Joint #4 timing belt
2-M4×5