
B-63783EN-1/01 1.AXIS CONTROL
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Basic Procedure
Thermal growth compensation is input by following the method.
1. The PMC drives the start signal THML high and sets the Thermal
growth compensation data signals THD00 to THD15.
2. The PMC then drives the strobe signal THSTB high.
3. When THSTB goes high, the control unit reads the data signals.
4. After all the signals are read, the control unit drives the read end
signal THREND high.
5. When THREND goes high, the PMC drives the strobe signal
THSTB low.
6. When the strobe signal THSTB goes low, the control unit drives
the read end signal THREND low.
After completing the data input procedure, allowing another data input
procedure is performed. The timing chart for the procedure above is
shown below.
1. 2. 3. 4. 5. 6.
Start signal THML
Start signal MTHML
Date signal THD00 to THD15
Strobe signal THSTB
Thermal growth compensation Data read (NC)
Read end signal THREND
Data Handling
The thermal growth compensation is always an absolute value, so the
tool moves by the difference between a new specified compensation
value and previous value.
When the sign of the thermal growth compensation is positive, this
function is treated as an extension of tool length.
When the sign of the thermal growth compensation data is negative,
this function is treated as a reduction of tool length.
The input of this function is a thermal growth along tool axis data.
And, the thermal growth of each axis by the angle of the tool is
calculated, and the amount of the compensation in the opposite
direction is output with the direction of thermal growth.
The relation between thermal growth and actual thermal growth
compensation is as follow.
In the calculation of the tool direction, calculation for the rotation axis
of the first group is made first, then based on the calculation result,
calculation for the rotary axis for the second group is made.