精密注射机在控制方面的特点
The characteristics of the precision injection machine in control
It
1) 对注塑成型参数的重复精度(再现性)要求高,宜采用多级注射反馈控制:
1) high accuracy (reproducibility) requirement for injection
molding parameters. Multi stage injection feedback control should be
adopted.
a.多级位置控制;
A. multilevel position control;
b.多级速度控制;
B. multistage speed control;
c.多级保压控制;
C. multistage pressure protection control;
d.多级背压控制;
D. multistage back pressure control;
e.多级螺杆转速控制。
E. multistage screw speed control.
位移传感器的精度要求达到0.1mm,这样可以严格控制计量行程、注射行程以及余料垫的厚度(射出监控点),保证每次注射量准确,提高制品成型精度。料筒及喷嘴温度控制要精确,升温时超调量要小,温度的波动要小。精密注塑应采用PID控制,使温度精确度在±0.5℃之间为宜。
The precision of the displacement sensor is required to reach
0.1mm, which can strictly control the metering stroke, the injection
stroke and the thickness of the residual cushion (shooting out the
monitoring point), so as to ensure the accuracy of each injection and
improve the molding precision of the products. The temperature control
of the barrel and nozzle should be precise. When the temperature rises,
the overshoot is small and the temperature fluctuation is small.
Precision injection molding should be controlled by PID, so that the
accuracy of temperature should be between 0.5 and C. Such
2)
塑化质量要求,塑料塑化的均匀性不仅影响到注塑件的成型质量,还会影响到熔融塑料通过浇口时所受阻力的大小,为了得到均匀的塑化,设计专用的螺杆和使
流水槽钢模具 不锈钢铸件 扭王字块模具 井盖钢模具 标志桩模具 调匝式消弧线圈 风冷控制柜 烤漆龙骨用专用的增塑技术必不可少。另外,机筒的温度也应精确控制,现在螺杆、机筒温度多采用PID控制(比例、微分、积分),精度可控制在±l℃内,基本可满足精密注塑的要求,如果采用FUZZY控制方法,就更适合于精密注塑了。
2) the quality of plasticizing is required. The uniformity of
plastic plasticization not only affects the molding quality of the
plastic parts, but also affects the resistance of the molten plastic
through the gate. In order to get the uniform plasticization, the design
of special screw and the use of special plasticizing technology is
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In addition, the temperature of the cylinder should be controlled
accurately. Now the temperature of the screw and barrel is mostly
controlled by PID (proportion, differential and integral). The precision
can be controlled within + L C, and it can basically meet the
requirements of precision injection molding. If FUZZY control method is
adopted, it is more suitable for precision injection molding.