7. POSITIONING CONTROL
7
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51
7.9 1-Axis Fixed-Pitch Feed Control
Positioning control to move the axis designated with the sequence program
positioning commands by the designated travel value from the current stop
position.
Fixed-pitch feed control uses the FEED-1 servo instruction.
Items Set by Peripherals
Common
Arc
Parameter Block
Others
Servo
Instruction
Positioning
Method
Number of
Controllable
Axes
Pa
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N
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.
Ax
is
A
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ode
T
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P
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Ra
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Cen
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Co
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it
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it V
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FEED-1
Incremental
1
∆
!
!
!
∆
∆
∆
∆
∆
∆
∆
∆
∆
∆
∆
OK
!
: Must be set
∆
: Set if required
[Control Details]
(1) Positioning control through the designated travel value from the current stop
position (0).
(2) The travel direction is designated by the sign of the travel value, as follows:
•
Positive travel value ............ forward direction (increased address)
•
Negative travel value........... reverse direction (decreased address)
V
t
Travel value
Commanded speed
Fixed-pitch feed using FEED-1 instruction
Reverse
direction
Forward
direction
Current stop position
Travel direction
for Negative sign
: indicates set data
Operation timing
Positioing direction
SVST
instruction
Travel direction
for Positive sign
Fig.7.23 1-Axis Fixed-Pitch Feed Control
POINT
Do not set the travel value to zero for fixed-pitch feed control.
If the travel value is set t o zero, fixed-pitch feed ends with no feed taking
place.
