Advancements in drive trains of injection mouliding maschines

Research Task/Objectives

Modern mechatronic fluid power drives feature well harmonized components in size and operation. Using system simulation power limitations may be predicted and the  components potential fully be used. In series machines this can be used to decrease cycle times and increase productivity significantly.

Clamping units of high-speed injection moulding machines are developed for high output in a short time. The highly nonlinear transmission rates of toggle-lever clamping units allow fast movements and high clamping forces. Excitations go along with high dynamics which may be obstructive for the production process. Advanced (feedforward) control techniques shall increase dynamics of an existing prototype. Special attention is drawn to an interface that is easy to use for the machine operator.

Approach/Results

The analytic description of the main physictechnical relations allows the calculus of motion-sets that guide the system along its boundaries.

User interaction is reduced to practical parameters (point of contact, maximum excitation). Control ensures that these conditions will not be exceeded. Model based feed-forward control reduces
contouring errors without any influence on
process stabilitiy.

The presented research activities are part of the project "Further development of electro-hydraulic drivetrains in injection moulding machines" (Ref. No. FKM Nr. 702160). The authors would like to thank the Fluid Power Research Fund of the VDMA for the funding and support.