Valco Cincinnati VC350A, Руководство пользователя

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7-8 Valco Cincinnati, Inc.
Section 7 - Initial Setup MC060 Manual/VC350AG AutoGlue Control System
When the glue pattern is set for 1.00 Start and 6.00 Stop, and the ratio
compensation switches are set to 1.0000, the following are true:
• 6.00 - 1.00 = 5.00 glue pattern requested
• Measured glue pattern = 4.75 inches
• 4.75 divided by 5.00 = 0.95
Therefore, the ratio compensation should be set for 0.9500. (The last two
digits can be adjusted to fine-tune the glue pattern. Increasing the ratio
compensation will shorten the pattern length and decreasing the ratio
compensation will lengthen the pattern length.)
Every valve, due to its inherent mechanical properties such as springs and
seals, has a specific time in which to open and close. From the instant a
valve receives an electrical signal to open, there is a time delay before the
valve opens and applies glue. This time delay is usually measured in
milliseconds (ms) and will vary depending on the type of valve. The same is
true for the off delay of the valve. Sometimes, the time delays are the same
for both the On and Off delays; however, they usually differ.
At faster speeds, the time delays may play a critical part in patterns and
accuracy. Therefore, if a valve takes 5.0 ms to open, a 5.0 ms compensation
time needs to be added to the start dimension. This will anticipate the start
dimension by 5.0 ms so the valve will open earlier in order to start at the
correct position on the box. Increasing the “on” delay will move the start
distance forward. Decreasing the “on” delay will move the start distance
backward at higher speeds.
The same procedure is used to set the “off” delay. If the pattern is too long,
increase the DS2 delay time to stop the valve sooner.
Therefore, when setting up a VC350AG control, keep the following in mind:
• The ratio compensation should be adjusted to achieve the
dialed pattern length selected on the thumbwheels at slow or jog
speed.
• The cell-to-gun parameter should be the measured distance
from the scanner to the valve, and not adjusted for glue
patterns. This adjustment will give the correct starting point of
the glue line at slow/jog speed.
• To finish the adjustments, the “on” and “off” compensation
delays should be adjusted at full speed to ensure pattern start
and length accuracy on each product .
The valve on/off compensation chart
should provide assistance in setting
these times. See Table 7-3 for
approximate switch setting delays.
Example of Adjusting
the Ratio
Compensation
Valve ON/OFF
Compensation
Theory of
Operation