LINEAR MOTOR DRIVEN VALVE
Quick Response – Acceleration & Deceleration
The injection response time is extremely important. It takes more time to reach a set speed if an injection response time is slower.
Figure: This chart shows a 0.016 sec. fill time molding application overlaying 20 shots. The injection reaction time is critical for repeating this process.
Red = Actual Speed
Brown = Actual Pressure
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Micro: Linear Direct Double Motor Valve – LP series
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Standard: Linear Servo Valve – TR, GL, HSP series
Micro Servo Valve: Double Linear Motor
Standard Servo Valve: Single Linear Motor
In order to control your molding process, your injection must follow its set parameter. When you consider injection capability, an important factor is not max injection speed, but how quickly it reacts, from 0 to max and max to 0.
RESPONSE TIME
(ms)
15
5
30
50
INJECTION STROKE
(mm)
3.75
1.25
7.50
12.50
1 ms = 0.001 sec
Injection Stroke to Reach Set Speed
Sodick uses the linear motor driven servo valve to increase its injection response. With this valve, the injection gains high acceleration and deceleration performance, as well as control of speed and pressure.
Comparison of Step Response
Drive System
Step Response (ms)
NC Loop Control (ms)
MICRO
Double Linear Motor Direct
2 ~ 3
50 (0.05ms)
ELECTRIC MACHINE
AC Servo + Ball Screw Drive
AC Servo + Pulley & Belt
25 ~ 40
62.5-100 (0.062 - 0.1ms)
STANDARD
Linear Motor + Pilot Valve
15 ~ 20
50 (0.05ms)