Multi-Material Mold for Standard Machines
Zahoransky Formenbau GmbH has introduced a newly developed multi-material mold with the designation Servo Cavity-Positioning System (SCPS). The process sequence differs considerably from previous mold systems used for multi-material injection molding such as rotary tables, indexing plates for stack/cube molds.
In the case of the SCPS approach, the mold is equipped with molded part carriers that move vertically from station to station in a manner reminiscent of what occurs in a paternoster elevator. These molded part carriers are located on the moving half (ejector side) the mold and are actuated by a spindle drive. The pre-shots are molded in the first station. Following this, the mold opens, and the spindle drive transports the molded part carrier with the pre-shots into the second molding station. The next material is molded onto the pre-shots the here. Upon completion of injection molding, the molded part carrier, together with the molded parts, moves to the part removal station above the mold. Here, a part handling system removes the parts from the carrier, while the next injection molding cycle is already starting in the closed mold. Finally, the empty part carrier is transferred to the stationary half (nozzle side) of the mold. The cycle is completed as a second spindle drive moves the part carrier back into the first injection molding station.
Because of its special design, the new multi-material mold is only minimally larger than a standard mold. Larger platens or extended tiebars are not required. All motions in the mold, including corepulls and needle shutoffs, are actuated by servo drives, making them independent of the machine’s hydraulics.