－
13
－
When the button is released, the magnet coil is deenergized and the movable core is returned by
spring to press the brake disk. The fixed core is divided into two parts (inside half and outside haft).
The inside half is set back 0.3- 0.4mm in height from the outside half. When the movable core is
pulled, the outside half comes into close contact with the movable core, but a gap (0.3- 0.4mm) will
be produced between the inside half and the movable core (this gap is necessary to eliminate
residual magnetic flux). Although the cores are not subjected to wear, long use of the brake may
cause reduction of this gap and reduced gap results in delay of brake action. If brake action comes
to delay, replace the fixed core assembly or grind the inside half to adjust the gap to 0.3 - 0.4mm. If
the gap is excessive, however, the motor shaft may not be released from the brake disk during
operation.
(1) Adjustment of brake
Remove the brake cover and turn the adjusting bolt screwed in the fixed core to adjust brake
force (torque).
Brake force increases when the adjusting bolt is turned clockwise, and decreases
when turned counter- clockwise. The adjusting bolt can be turned each 60°.
Table 1 shows the relationship between dimensions “A” of adjusting bolt (Fig. 25)
and brake force (motor rated torque: 100%).
Saddle model
ST-0.2D Type
SP-0.2D Type
ST-0.4D Type
SP-0.4D Type
ST-0.4-U Type
ST-0.75D Type
ST-0.75-U Type
ST-2.2D Type
Motor torque
(N
・
m)
1.67 2.55 4.81 14.03
MAX
18
(80%)
16.5
(130%)
38
(115%)
33.6
(50%)
Factory
setting
22
(50%)
22
(65%)
41.6
(60%)
35.2
(30%)
Dimension A
(mm)
0%
27.5 27.5 45.3 37.6
Fixed core
Adjusting bolt
Fixed core
Adjusting bolt
Adjustable
Adjusting
bolt
Adjustable
Adjusting
bolt
Fig. 24-1
Fig. 24-2
Fig. 25
