Maintenance 2. General Maintenance
2.4 Tightening Hexagon Socket Head Cap Bolts
Hexagon socket head cap bolts are used in places where mechanical strength is required.
(A hexagon socket head cap bolt will be called a “bolt” in this manual.) These bolts are
fastened with the tightening torques shown in the following table.
When it is necessary to refasten these bolts in some procedures in this manual (except
special cases as noted), use a torque wrench so that the bolts are fastened with the
appropriate tightening torques as shown below.
Bolt Tightening Torque Refer below for the set screw.
M3 245 N⋅cm (25 kgf⋅cm) Set Screw Tightening Torque
M4 490 N⋅cm (50 kgf⋅cm) M4 245 N⋅cm (25 kgf⋅cm)
M5 980 N⋅cm (100 kgf⋅cm) M5 392 N⋅cm (40 kgf⋅cm)
M6 1,760 N⋅cm (180 kgf⋅cm)
M8 3,720 N⋅cm (380 kgf⋅cm)
M10 7,350 N⋅cm (750 kgf⋅cm)
M12 12,740 N⋅cm (1,300 kgf⋅cm)
We recommend that the bolts aligned on a circumference should be fastened in a crisscross
pattern as shown in the figure below.
1
5
3
7
2
6
4
8
Bolt hole
Do not fasten all bolts securely at one time.
Divide the number of times that the bolts are
fastened into two or three and fasten the bolts
securely with a hexagonal wrench. Then, use
a
torque wrench so that the bolts are fastened with
tightening torques shown in the table above.
2.5 Matching Origins
After parts have been replaced (motors, reduction gear units, a brake, timing belts, a ball
screw spline unit, etc.), the Manipulator cannot operate properly because a mismatch
exists between the origin stored in each motor and its corresponding origin stored in the
Controller. After replacing the parts, it is necessary to match these origins.
The method of calibration is different depending on the software used. Refer to
Maintenance: 13. Calibration and follow the steps that pertain to the software you are
using.
For calibration, the pulse values for a specific position must be recorded in advance.
Before replacing parts, select easy point (pose) data from the registered point data to check
the accuracy. Then, follow the steps below to display the pulse values and record them.
EPSON
RC+
Execute the following command from the [Command Window].
>PULSE
PULSE: [Joint #1 Pulse value] pls [Joint #2 Pulse value] pls [Joint #3 Pulse value]
pls [Joint #4 Pulse value] pls
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