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No. 99MBC071A
1) Diameter detection method
• This is used to automatically detect a workpiece that enters the laser scanning plane
perpendicularly.
• For actual detection of a workpiece the displayed measurement (after calibration and
offset) is used.
• One session of automatic detection consists of no workpiece being detected, detec-
tion of a workpiece with a dimension that is within the detection range (between the
upper and lower detection limits), an invalidation period required to exclude invalid
dimensions (of chamfered portions, etc.) from the measurement, and effective
measurement for the specified number of times. The final measurement result will be
latched (held) on the display. Once entering the effective measurement the upper and
lower detection limits will no longer be checked.
• The speed of workpiece detection (i.e. the number of scans) can be specified as
either 1 or 16 in the basic setup.
• Use 16 times in the following cases:
* If connecting bars are used between workpieces for feeding convenience and for
setting appropriate intervals between workpieces, and, if the difference in the
outside diameter between the workpiece and the bar is insufficient.
* If the feed rate is low.
• The following diagram is an example where a workpiece with a chamfered outside
diameter of D mm and a length of
mm moves at a velocity of V mm/s.
D
a
c
g
Scanning beam
Workpiece flow V mm/s
Setting example:
• Lower detection limit: L < (a +D) / 2
• Upper detection limit: H > Upper limit of the measuring range or 1.1 D
(This setting may be omitted.)
• Invalidation period : T > (c / V) ms
• Number of measurements: N < ( - 2c) x 0.8 (safety factor) / measurement interval / V
