
B-65270EN/05 4.SERVO FUNCTION DETAILS
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NOTE
1 If the brake is in use, it starts working while the
vertical axis is being lifted. So the distance through
which the axis is actually lifted differs from the setting.
2 Whether the parameter values is positive or negative
matches whether the machine coordinate value is
positive or negative.
3 Using this function causes the load to stop after
moving it to one side of the machine. So, it should be
used for the vertical axis (Z-axis) of a vertical
machining center in which an axis retracts in a fixed
single direction at an emergency stop.
2787 (FS15i)
Lifting time
2374 (FS30i, 16i)
This parameter determines the lifting time as measured from the time
of an emergency stop. The distortion easing function is executed after
the lifting time has elapsed. This function is intended to decrease the
amount of machine elastic strain that can increase when a vertical axis
is lifted when the machine is about to apply the brake. Executing this
function can reduce the shock that may occur when the axis drops
because the servo amplifier stops energizing. The initial value of the
function is a quarter of the distance to lift.
(See the following figure.)
[Unit of data] ms
[Valid data range] 8 to 32767
[Recommended value] Approximately 16 or 24 ms
NOTE
1 Specify an integer multiple of 8 as the lifting time
2 To use the lifting function against gravity at
emergency stop, specify 8 ms or longer as the
lifting time.
3 If the distortion easing function is not used, specify
the time longer than or equal to the one set in the
brake control timer as the lifting time.
• Velocity command
ertical axis lifting
Distortion
easing
function
Lifting time
Fig. 4.11.3 (a) Velocity command