Active Core Micro Moulding Resonator Dimensional Control
Active core micro moulding controls resonator dimensions by displacing sub-micron pins during fill, suppressing volumetric sink and frequency drift.
Active Core Micro Moulding
Meaning
Injection moulding processes utilizing dynamic core pins during the filling stage represent a highly advanced method for producing high-precision miniature components. In active core micro moulding, the core pin shifts its position in real time to balance the melt flow in micro-scale cavities. This method prevents core deflection and helps achieve uniform wall thicknesses in high-aspect-ratio micro-parts.
Process Mechanism
Actuators embedded in the mould plate drive the core pin with sub-micron precision. During the injection phase of active core micro moulding, sensors measure the cavity pressure and signal the actuator to adjust the core’s position. This dynamic adjustment counteracts the high injection pressures that would otherwise bend a static micro-core.
Dimensional Control
Precision micro-moulded parts demand tolerances below five micrometres. The use of active core micro moulding allows moulders to compensate for batch-to-batch viscosity variations in virgin resin. Regrind economics are rarely viable here because even minuscule material variations can lead to part rejection.
A steady, predictable viscosity ensures the dynamic core maintains the required volume without over-pressurizing the micro-features. This ensures that the final part conforms exactly to the datasheet specifications.
Tooling Requirement
Micro-machining and specialized steel selection are necessary to build these dynamic systems. Clearance between the moving core and the cavity wall in active core micro moulding must be less than two micrometres to prevent flash. Hardened tool steels ensure the sliding surfaces do not wear out.