VT6L Maintenance  11. Joint #3 
 
VT series Maintenance Manual    Rev.2  89 
 
the timing belt through the motor pulley and 
oosely secure to the Arm #2. 
Hexagon socket head cap bolts: 3-M4×22 
(with slotted hole washer) 
Make sure that the gear grooves of the timing belt are fit into those
 of the pulley 
 
When securing the motor unit loosely, make sure that the motor unit
 can be moved 
by hand and it does not tilt when being pulled.
    If the unit is secured too loose or 
too tight, the belt will not have
 proper tension. 
As shown on the picture, pass the cable through 
the rear 
the Arm #2 motor unit fixing part. 
the motor unit, make sure that the cables are 
the gap between the motor unit and Arm #2.   
the thermal conductive sheet on the rear side of the 
the round convex part at the end of the Arm 
 
 
Apply proper tension to the motor unit and 
fix it. 
Joint #3 timing belt tension: 34 - 58 N 
Belt tension meter setting values 
Weight: 2.5g/mm width×m span 
Width: 9.0mm 
Span: 169mm 
Hexagon socket head cap bolts: 3-M4×22 (with slotted hole washer) 
Tightening torque: 4.0 ± 0.2 N·m 
 
Jumping (position gap) may occur if the value is below the lower limit.
 
Vibration (abnormal noise) or reduction in life of the parts may occur if the value 
exceeds the upper
 limit. 
When you replace with a new belt, belt extends and the belt tension may decrease in 
the initial stage.
 
Make sure to operate the robot two to three days and check the belt 
tension again