Mitsubishi Electric MELSEC-L LD75P User Manual page 415

(6) 3-axis helical interpolation control with center point designation (INC helical
right, INC helical left)
(a) Operation chart
In this control, positioning is carried out from the current stop position (X0, Y0, Z0) to the movement amount
position (X1, Y1, Z1) set in "[Da.6] Positioning address/movement amount". Circular interpolation with an arc
path having its center as the address of the center point (arc address) set in "[Da.7] Arc address" is carried out.
Simultaneously, linear interpolation is carried out with the other linear axis. The control path is helically rotated
for the number of pitch set in "[Da.10] M code" of the linear axis to complete the positioning to the specified
position.
Operation chart
Z axis
Y axis
X axis
Positioning of a true circle with a radius of the distance from the start point address to the arc center point can
be carried out by setting the movement amount of the circular interpolation axis to "0".
Operation chart
Z axis
Y axis
X axis
(b) Restrictions
3-axis helical interpolation control cannot be set in the following cases.
• When "degree" is set in "[Pr.1] Unit setting" for the reference axis and circular interpolation axis
• When the units set in "[Pr.1] Unit setting" are different between the reference axis and circular interpolation
axis. ("mm" and "inch" combinations are possible.)
• When a method other than "reference axis speed" is set in "[Pr.20] Interpolation speed designation method"
or "[Da.29] Interpolation speed designation method"
Circular interpolation control
end point (X1, Y1)
Linear control end point (Z1)
Arc center point
Number of pitch
Linear movement
amount
Circular interpolation control
start point (X0, Y0)
Linear control start point (Z0)
Circular interpolation control
end point (X1, Y1)
Linear control end point (Z1)
Arc center point
Number of pitch
Linear movement
amount
Circular interpolation control
start point (X0, Y0)
Linear control start point (Z0)
CHAPTER 9 MAJOR POSITIONING CONTROL
Circular interpolation plane
Circular interpolation control
end point (X1, Y1)
Center point
Movement amount
Movement
to the end point
amount to
Radius
the center
Circular interpolation control
start point (X0, Y0)
Circular interpolation plane
Center point
Radius
Circular interpolation control
start point (X0, Y0)
Circular interpolation control
end point (X1, Y1)
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