Rockwell Automation 1771-QDC, D17716.5.85(Passport) MNL. PLASTIC MOLDING MODULE - Manual (Page 13)

Overview of Inject Mode
Chapter 1
1-2
Figure 1.1
Inject Operation of a Typical Machine Cycle
Injection Pack Hold
Post- Pre-
Decompression Decompression
Plastication
(Reload)
Transition to
Pack or Hold
Clamp
& Eject
Operation
Injection Phase
You can vary the velocity of the ram (screw), or the pressure driving it, so
the leading edge of the melt moves through the mold cavity at the desired
speed. The pattern of velocity or pressure variation during injection is
called the injection profile. The QDC module lets you chose from four
different injection profiles:
velocity vs. position
pressure-limited velocity vs. position
pressure vs. position
pressure vs. time
Figure 1.2
Example Injection Profile
11 10 9 8 7 6 5 4 3 2 1
Position or Time
Velocity
or
Pressure
You enter setpoints to create a profile. You can select from 1 to 11
segments of position or time. Segment numbers represent the order of
operation. By convention the ram (screw) injects plastic by moving from
right to left.