enEnglisch
Research and Development
Technology transfer
"Piezo-based volume dosing for micro injection moulding"
Problem
The demand for high-precision post-processing-free components for numerous plastic micro-moulded parts requires novel technical{j} solutions in micromechanics, micro-optics and microelectronics. For the precise dosing and injection of these minimal amounts of melt, particularly high demands are placed on the dosing and injection units. One solution is provided by the piezo-based volumetric dosing in the form of a unit that can be adapted to injection moulding tools. In addition to the development of actuators for generating the dosing stroke and pressure, the necessary partial solutions require solutions for temperature control and storage of very small amounts of melt. Associated with this are the mastery of tribological and adhesive problems on surfaces in contact with the melt, as well as the thermal insulation of thermally sensitive electronic and mechatronic components.
A way to a solution
One of the most important functional elements is the design of the dosing and closure system, which is activated via the piezo technology. Specific challenges arise in the development of the pressure-resistant closure of the melting chamber and the design of closing and functional surfaces that come into contact with the melt. Solution variant 1: The precise amount of melt to be dispensed is controlled by the opening time of the closure system.
Differentiated design and material measures are required to prevent undesirable melting, which is detrimental to the function. The focus is on anti-adhesive coatings and dynamic tempering. The implementation of the necessary dosing strokes and pressures is achieved through the development of a piezo drive. Solution variant 2: The dosed amount is controlled by the dosing stroke by applying pressure to the melt-filled dosing chamber with a piezo actuator. Depending on the dosing pulse, there is a different volume displacement, with the melt being forced through the outlet opening (nozzle) from the dosing chamber in the direction of the cavity. Special requirements arise here for the development of the pressure transmission mechanism.
Application possibilities
All in all, the precise volumetric dosing on the basis of a piezo-actuator offers the opportunity to economically mould miniature and micro plastic parts in high quality. The {j} company achieves a further economic profile with regard to the micro and very small quantity dosing of highly viscous media. In addition, KDS is able to develop and configure dosing solutions for related applications that play a major {j} role in a variety of technical processes. In addition to the considerable increase in competence, there is the opportunity to develop a market niche in this area and to achieve a unique selling point.
