3. INTERPOLATION FUNCTIONS
B–63522EN/02
NC FUNCTION
52
The function in which contour control is done in converting the 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) is the polar coordinate interpolation. It is an effective
function when a straight line groove is cut on the outer diameter of a
workpiece or when a cam shaft is ground.
Whether the polar coordinate interpolation is done or not is commanded
by a G code.
These G codes shall be commanded in a single block.
G12.1; Polar coordinate interpolation mode
(Polar coordinate interpolation shall be done.)
G13.1; Polar coordinate interpolation cancel mode
(Polar coordinate interpolation is not done.)
The axes (linear axis and rotary axis) on which polar coordinate
interpolation is done are set beforehand by parameters.
Change the mode to polar coordinate interpolation mode by commanding
G12.1, and a plane (hereinafter referred to as polar coordinate
interpolation plane) is selected in which linear axis is made to the first
axis of the plane, and virtual axis being a right angle with the linear axis
is made to the second axis of the plane. Polar coordinate interpolation is
carried out on this plane.
In the polar coordinate interpolation made, the command of linear
interpolation (G01) and circular interpolation (G02, G03) is possible.
And both absolute command (G90) and incremental command (G91) are
possible.
For the program command it is possible to apply cutter compensation.
For the path after cutter compensation is done, polar coordinate
interpolation can be made.
As for feedrate, specify the tangential speed (relative speed between the
workpiece and the tool) on the polar coordinate interpolation plane
(cartesian coordinate system) with F.
The polar coordinate interpolation cancel mode is obtained by G13.1
command.
3.7
POLAR COORDINATE
INTERPOLATION
(G12.1, G13.1)
Format
Explanations
D Polar coordinate
interpolation mode
(G12.1)
D Polar coordinate
interpolation cancel
mode (G13.1)