Mitsubishi Electric RH-3FH Series Instruction Manual page 110

5 Maintenance and Inspection
8) Next, adjusts the tension of the timing belt A <1>.
Lightly loosen two J4 motor fixing screws <7> (Be careful not to overly loosen the screws.).
9) Loosen the nut of tension adjustment screw <8> for timing belt A. Adjusts by turning the tension adjustment
screw <8> slowly and moving the J4 axis motor <9> little by little.
When the screw is turned to the right, the belt will be stretched, and when turned to the left, will loosen.
Adjust tension to the above-mentioned value.
Note) Be careful, if the belt is removed from pulley <10> <4>, or the mesh of belt and pulley <10> <4> is
shifted by loosening the screw too much, the origin will deviate. If the position deviated, reset the
origin. (Refer to
<The No.2 arm upper view (Inside of the No.2 arm cover U)>
<7> J4 axis motor fixing screw
(two screws)
*Exists in the rear of J4 axis also
<The No.2 arm bottom view (Inside of the No.2 arm cover D)>
10) After adjustment, fasten certainly the two J4 motor fixing fixing screws <7> And fasten certainly the nut of
tension adjustment screw <8>. Improper tightening may cause the belt to loosen with vibration.
11) Install No.2 arm cover U and No.2 arm cover D securely as before and finish adjustment.
This completes adjustment of the J4 axis timing belt.
Maintenance and inspection procedures
5-97
Page 110, "5.6 Resetting the
*The RH-6FH/12FH/20FH series is also equivalent although the figure is RH-3FH.
*The RH-6FH/12FH/20FH series is also equivalent although the figure is RH-3FH.
origin")
<8>Tension adjustment screw for
timing belt A
Loosen the nut and screw
<1> Timing belt A
Push
<9>J4 axis motor
<1>Timing belt A
<10>Timing pulley A
<4>Timing pulley B