Method for the multicomponent injection molding of plastic parts

A method and an apparatus of the generic type are known from DE-OS 22 59 818. Different plastic materials are melted there in two or more plasticizing units, and are injected into an injection molding tool by a special, controllable multicomponent injection nozzle. This nozzle has a quite complicated structure, for the precise control of the individual melt streams of the respective plastic components. A method for the multi-component injection molding of plastic parts, in which at least two different plastic components are injected into an injection molding tool to form a plastic part, the method comprising the following steps: a) introducing a first plastic component into a melt accumulation chamber, which is bounded by a piston-like end section; b) subsequently introducing a second plastic component into the melt accumulation chamber; c) transferring plastic melt accumulated in the melt accumulation chamber into the injection molding tool. In one embodiment the pressure conditions in the cavity region are homogenized. For this purpose the invention specifies that, when the plastic melt is transferred in accordance with the above step c), the piston-like end section of the melt accumulation chamber is moved in such a way that it forms part of the cavity wall of the injection molding tool.