User's Guide

24
Probe moves
Probe trigger
A probe trigger signal is generated when the
probe’s stylus is driven against a surface.
The machine control records the contact
position and instructs machine motion to stop.
To ensure a trigger signal, drive the probe
against the workpiece to a target beyond the
expected surface, but within the limits of stylus
overtravel. After the probe stylus touches the
surface, reverse clear of the surface.
Single and double touch probing
If the probe operating sequence is based on a
single touch, then the probe is returned to its
start point following a measuring move.
On some types of controller, it is desirable to
use a two touch method, as poor accuracy and
repeatability can result at higher feed rates.
With a double touch sequence the first move finds
the surface quickly. Then the probe is backed off
to a position clear of the surface, before making
the second touch at a slower feed rate, thereby
recording the surface position at a higher
resolution.
Probe measuring speed
The probe system transmission delay time is
small and constant. It does not normally limit the
probing speed, because it is cancelled out during
calibration of the probe on the machine tool.
High probing speeds are desirable, however if
used, a probing velocity must be chosen which
allows the machine to stop within the limits of
stylus overtravel, and measuring capability of
the machine.
Probe moves