© MOOG 2019
This document is subject to MOOG INTELLECTUAL AND PROPRIETARY INFORMATION LEGEND . The details are on page II.
3
MRJ06301
Accumulator feedback detector is used for accumulator type blow molding machine. The DigiPack
Ⅲ
changes the target core position while monitoring the signal from this detector.
1.2.1.1.
Continuous blow molding machines
Figure 1-2 B
asic Continuous Blow Molding Machine Control Diagram
When used with continuous blow molding machines, the
DigiPack
Ⅲ
controls the parison wall thickness
relative to the machine cycle time. The machine cycle starts when the start signal is input (when the parison
cutting knife disconnects the parison). The cycle time can be determined by the following.
a) Fixed cycle time set by the operator (when [Auto cycle] is OFF)
b) Automatic cycle time set by repeatedly measuring the time between start signals (when [AUTO CY-
CLE] is ON)
When using the fixed cycle time of a), it is necessary for the machine operation time to be negligible for
reasons such as multiple die interlocking, or It is a premise that it is a machine that performs machine
functions such as closing and moving molds within the cycle time
The shape of the parison wall profile is set digitally by the operator. The size of the die gap, measured by
a die gap position transducer, is compared with the operators commanded position as set on the
DigiPack
Ⅲ
display.
The error between the operators set position and the actual position causes the servovalve to flow oil to
the actuator to reduce the position error to a very small value. This feedback process ensures that the
actual die gap follows the commanded die gap very accurately.
With a continuous blow molding machine, DigiPack
Ⅲ
operates / processes as follows.
①
The operator sets the core position (core die gap opening / closing amount) necessary to obtain the
desired wall thickness (usually constant wall thickness) product on the DigiPack
Ⅲ
controller panel.
②
When the start signal switches from OFF to ON, DigiPack
Ⅲ
controls the servo valve so that the core
follows the set position according to the cycle time.
③
The servo valve adjusts the flow rate to the core actuator according to the (flow rate) command from
DigiPack
Ⅲ
.
Hydraulics
Die Gap
Tooling
Actuator
PLC Controller
Servovalve
Actuator
DCDT
Core Position
Parison Cutoff Knife
