Table of Contents
Advertisement
Probing feed rate
and spindle speed
6 – 374
The probing feed rate from MP6520 is used for tool measurement with a
nonrotating tool.
The TNC automatically calculates the probing feed rate and the spindle speed
for tool measurement with rotating tool. The speed is calculated from the
maximum permissible surface cutting speed (MP6570) and the tool radius in
the tool table:
7 7 7 7
Enter MP6500 bit 4 = 0.
7 7 7 7
In MP6572, enter the maximum permissible speed.
7 7 7 7
In MP6570, enter the maximum permissible surface speed of the tool edge.
The control calculates the speed from the following formula:
MP6570
--------------------------- -
n
=
⋅ ⋅ ⋅
-3
2 π r 10
n: Speed [rpm]
MP6570 = Maximum permissible surface speed of the tool edge [m/min]
r: Tool radius [mm]
High frequency spindles often cannot function at speeds under 1000 rpm:
7 7 7 7
In this case enter MP6500 bit 4 = 1, in order to always use the lowest
possible speed for that spindle. This is automatically calculated by the TNC.
MP6570 and MP6572 then are without function.
The probing feed rate is calculated from the revolutions per minute and the
measuring tolerance defined in MP6510.0.
7 7 7 7
In MP6510.0, enter the maximum permissible measuring error, the so-
called measuring tolerance.
v = measuring tolerance · n
v: Probing feed rate [m/min]
Measuring tolerance: Measuring tolerance [mm] from MP6510.0 depending
on MP6507
n: Speed [rpm]
7 7 7 7
With MP6507, specify the type of calculation of the probing feed rate.
MP6507=0: Calculation of the probing feed rate with constant tolerance
The measuring tolerance remains constant, regardless of the tool radius. For
large tools, however, the probing feed rate becomes so small that it falls
below the smallest programmable increment and becomes zero. The smaller
the maximum surface cutting speed and the measuring tolerance, the sooner
this effect begins.
MP6507=1: Calculation of the probing feed rate with variable tolerance
The measuring tolerance changes depending on the tool radius. A probing
feed rate results even for large tool radii.
HEIDENHAIN Technical Manual TNC 426, TNC 430
Advertisement
Table of Contents
