scholarly journals Injection Velocity Control of Thermoplastic Injection Molding via A Double Controller Scheme

1999 ◽  
Vol 38 (9) ◽  
pp. 3396-3406 ◽  
Author(s):  
Yu-Chu Tian ◽  
Furong Gao
2004 ◽  
Vol 16 (4) ◽  
pp. 348-354
Author(s):  
Noriyuki Akasaka ◽  

With the trend toward higher-power electric-motor-driven injection molding machines, multi-AC servomotor control is needed to control the molding machine, making synchronous positioning control inevitable to prevent excessive mechanical stress in equipment. Synchronous positioning control in injection velocity control is implemented by using position feedback signals from motor pulse generators. In injection pressure control synchronous positioning control is difficult to realize because pressure-detector signals are used in place of position feedback signals. We clarified synchronous positioning control during injection pressure control by using both pressure-detector and position feedback signals. Simulation results showed that synchronous positioning control error was less than ±4μm in pressure control.


2020 ◽  
Vol 14 (4) ◽  
pp. 423-427
Author(s):  
Emir Šarić ◽  
Samir Butković ◽  
Muhamed Mehmedović

The volumetric flow rate (injection velocity) and the holding pressure are metal injection molding (MIM) parameters that have a strong influence on the green parts density and density homogeneity, but their effect on sintered dimensions after sintering is still to a large extent unexplored. To reveal the relationship between the injection molding parameters and sintered dimensions, ring-shaped components were injection molded by using different values of injection velocities in combination with a rump-down and rumpup holding pressure profile. Afterwards, the green components were catalytically debound and sintered in the nitrogen (N2) atmosphere. Finally, the component dimensions: the height, inner and outer diameter were measured by using a coordinate measuring machine. The ready-to-mold granules Catamold 310N made of heat resistant stainless steel X40CrNiSi 25-20 (according to the EN standard) powder and polyacetal based binder were used. The results showed that the interaction between the injection velocity and the holding pressure profile can be used to systematically adjust shrinkage after sintering. This approach is based on the dependence of the binder crystallization temperature on pressure, when the powder/binder proportion changes with the injection velocity.


2012 ◽  
Vol 501 ◽  
pp. 190-195
Author(s):  
Lian Shuai Chen ◽  
Hui Min Zhang ◽  
Jia Teng Niu

Rubber injection molding is applied in more and more applications in rubber production process. Design of gating system is the most important in rubber injection mold design. Poor runner design will lead to uneven injection velocity and pressure which affect the size and shape and the quality of the rubber products. This paper first adopted POLYFLOW numerical simulation. Three different inlet flow rates for multi-cavity mold were simulated and analyzed by POLYFLOW software in this paper. Non-equilibrium gating system was further optimized by the calculation method of Balanced Gate Value and numerical simulation. The best inlet flow rate and the best runner size were ultimately obtained. It was proven that Numerical simulation results are of great significance for rubber injection mold design and injection molding processing parameter selection.


2015 ◽  
Vol 4 (1) ◽  
Author(s):  
Rossella Surace ◽  
Vincenzo Bellantone ◽  
Gianluca Trotta ◽  
Vito Basile ◽  
Francesco Modica ◽  
...  

This paper reports on design, fabrication, and characterization of a microfilter to be used in biomedical applications. The microfilter, with mesh of 80 μm, is fabricated by micro-injection molding process in polymeric material (polyoxymethylene (POM)) using a steel mold manufactured by micro-electrical discharge machining process. The characteristics of the filter are investigated by numerical simulation in order to define a suitable geometry for micro-injection molding. Then, different process configurations of parameters (melt temperature, injection velocity, mold temperature, holding pressure and time, cooling time, pressure limit) are tested in order to obtain the complete part filling via micro-injection molding process preventing any defects. Finally, the component is dimensionally characterized and the process parameters optimized to obtain the maximum filtration capacity.


2007 ◽  
Vol 364-366 ◽  
pp. 53-57 ◽  
Author(s):  
Yung Kang Shen ◽  
Yi Lin ◽  
Jeou Long Lee ◽  
Fwu Hsing Liu ◽  
Chih Wei Wu ◽  
...  

This research first indicates the melt front delay of wedge-shaped lightguiding plate of backlight module on micro injection molding. This research fabricated the patterns of mold insert of lightguiding plate by photo etching process. The micro-facture of lightguiding plate was manufactured by micro injection molding. The lightguiding plate of backlight module was used for the PMMA material. The single parameter method was used to discuss the flatness and replication properties for different processing parameters (mold temperature, melt temperature, packing pressure, packing time and injection pressure). The results show that there are melt front delays due to the slow injection velocity, the low temperature induced by the little effect of shear heating, the high viscosity, the large flow resistance and the slow flow velocity. The mold temperature is the most important factor for the flatness and the replication of micro-feature of liughtguiding plate. Lower mold temperature induces better flatness properties. The surface roughness of micro-facture of lightguiding plate is 8.8 nm on micro injection molding for this work.


2012 ◽  
Vol 629 ◽  
pp. 576-580
Author(s):  
Lan Fang Jiang ◽  
Hong Liu ◽  
Chang Guo Hu ◽  
Xian Li Chen ◽  
Zhi Jiang Lei

Due to large planar scale and small lateral scale of plastic drawing board, it was easy to cause warpage problem in injection molding. Optimization of injection molding process was taken to reduce residual stress and improve quality. Combining orthogonal experimental method and software Moldflow, analyzed the effect of mold temperature, melt temperature, hold pressure and injection velocity on warpage deformation. It changed multi-objective optimization to single-objective optimization by weighted method. Through range analysis obtained the influence trend between parameters and comprehensive optimal object. Lastly got the optimal combination of injection molding process parameters.


Sign in / Sign up

Export Citation Format

Share Document