2.6.4 Replacing Axis 4 Timing Belt
• When the axis 4 timing belt is replaced with a new one, the axis 3 should be
disassembled also due to the structure. Therefore, strictly observe the
cautions on replacement of the axis 3 timing belt and motor also.
• When the ball screw nut integrated with the ball screw spline shaft is
disconnected, take utmost care not to cause the ball screw spline shaft to come
off. Otherwise, the ball in the ball screw nut will drop and the ball screw nut
integrated with the ball screw spline shaft cannot function any further.
1) Remove the arm 2 cover. (See Para. 2.4.1.)
2) Disconnect all connectors which are set to the connector plate.
3) Disconnect the axis 3 motor base which remains attached with the motor and
pulley. For the disconnecting procedures, see Para. 2.5.7.
4) Dismount the axis 3 timing belt.
5) Cut the TY-RAP for the cables secured to the axis 4 motor base plate.
6) Loosen the axis 4 tension adjustment bolt (M5 × 30), remove the flange head
bolts (M5 × 16) securing the axis 4 motor base, then pull out the motor base
upward.
7) Remove the two (2) bolts (M5 × 10) securing the guide to disconnect the guide.
8) Remove the tool flange and stopper. (The hand, etc. should be disconnected
beforehand.)
9) Disconnect the axis 3 nut pulley secured to the ball screw nut. When removing
the clamp bolts (M6 × 20), the pulley will rotate. Secure the pulley, using the
holes (ø6 drill; four (4) places) machined on the pulley.
10) Remove the four (4) bolts (M5 × 16) securing the nut flange, then carefully draw
out the ball screw nut integrated with the shaft upward. If the ball screw nut
integrated with the shaft is drawn out diagonally with an unusually large force,
the ball in the ball screw nut may drop.
STE 85306
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