Replacing The Timing Belt: G20 - Epson G Series Maintenance Manual

G10 G20 Maintenance 8. Joint #4

8.2.2 Replacing the Timing Belt: G20

A brake is mounted on the motor of Joints #3 and #4 to prevent the shaft from moving down
due to the weight of the end effector while the power to the Controller is OFF or while the
motor is in OFF status (MOTOR OFF).
Note that the brake will not work during the replacement procedure.
Move the shaft down to its lower limit before starting the replacement procedure by
following the removal steps.
U belt (1) Turn ON the Controller.
Removal: G20
(2) Push down the shaft to its lower limit while pressing the brake release switch. Be sure
(3) Turn OFF the Controller.
(4) Remove the arm top cover and the arm bottom cover.
(5) When you use the plate of 4-mounting plate, remove
(6) Loosen the Z belt.
426
to keep enough space and prevent the end effector hitting any peripheral equipment.
The brake release switch is applied to both Joints #3 and #4. When the brake release
switch is pressed, the respective brakes of the Joints #3 and #4 are released
simultaneously.
Be careful of the shaft falling and rotating while the brake release switch is being pressed
because the shaft may be lowered by the weight of an end effector.
For details, refer to 3. Covers.
the plate.
When you use the plate of 3-point mounting, loosen
the plate mounting bolts.
Be sure to keep the connectors connected to the
battery unit.
If connectors of the battery unity are disconnected,
you need to perform calibration again.
Loosen four bolts on the Joint #3 motor unit. Slide
the Joint #3 motor unit to the end of the arm.
4-point mounting
4-M4×10
Plate
Battery unit
3-point mounting
Battery unit
Plate
4-M4×15
+ Washer
Joint #3
motor unit
G series Maintenance Rev.3