4. INTERPOLATION FUNCTIONS
Polar coordinate interpolation is a function that exercises contour control
in converting a command programmed in a Cartesian coordinate system
to the movement of a linear axis (movement of a tool) and the movement
of a rotary axis (rotation of a workpiece). This method is useful in cutting
a front surface and grinding a cam shaft on a lathe.
Starts polar coordinate interpolation mode (enables
polar coordinate interpolation)
Polar coordinate interpolation mode is cancelled (for
not performing polar coordinate interpolation)
Specify linear or circular interpolation using coordinates
in a Cartesian coordinate system consisting of a linear
axis and rotary axis (virtual axis).
G112 and G113 can be used in place of G12.1 and G13.1,
G12.1 starts the polar coordinate interpolation mode and selects a polar
coordinate interpolation plane (Fig. 4.5 (a)). Polar coordinate
interpolation is performed on this plane.
Rotary axis (virtual axis)
(unitmm or inch)
(unit:mm or inch)
Fig4.5 (a) Polar coordinate interpolation plane.
Origin of the workpiece coordinate system
When the power is turned on or the system is reset, polar coordinate
interpolation is canceled (G13.1).
The linear and rotation axes for polar coordinate interpolation must be set
in parameters (No. 5460 and 5461) beforehand.
The plane used before G12.1 is specified (plane selected
by G17, G18, or G19) is canceled. It is restored when G13.1
(canceling polar coordinate interpolation) is specified.
When the system is reset, polar coordinate interpolation is
canceled and the plane specified by G17, G18, or G19 is
D Specify G12.1 and G13.1
in Separate Blocks.
D Polar coordinate