
B-65280EN/05 FANUC AC SPINDLE MOTOR αi series 2.EXPLANATION OF OPERATION MODES
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2.2.12 Calculating the Orientation Time
The time required for orientation differs between the first orientation
(before the one-rotation signal has first been detected) and the second
and subsequent orientations (once the one-rotation signal has been
detected).
(1) Before the one-rotation signal has first been detected(first
orientation)
The time, from the input of an orientation command until
orientation stops, is divided into four periods.
In the following figure, A indicates that the motor in the stop
state starts rotating and is accelerated to the orientation speed. B
indicates that the already rotating motor is decelerated to the
orientation speed.
t
1
: Time required to achieve orientation speed Nori [sec]
t
2
: Time from the detection of a one-rotation signal (0 to 1 rotation) after Nori is achieved, until the
number of pulses output before the next one-rotation signal has been checked [sec]
t
3
: Time from the completion of the checking of the number of pulses until deceleration starts [sec]
t
4
: Time from the start of deceleration until orientation is completed [sec]
Motor speed
Time
(a) Normally, t
1
is measured on the actual machine.
Orientation speed Nori [min
-1
] is calculated from position
gain PG [sec
-1
] and the motor speed limit ratio for
orientation Rori.
Rori60PGNori
(b) t
2
is the time required for the motor to rotate one to two
turns at orientation speed Nori [min
-1
].
RoriPG
2
t
RoriPG
1
Nori
602
t
Nori
601
2
2
×
≤≤
×
∴
×
≤≤
×
(c) t
3
is the time required for the motor to rotate zero to one
turns at orientation speed Nori [min
-1
].
RoriPG
1
t0
Nori
601
t
Nori
600
3
3
×
≤≤∴
×
≤≤
×