Mixing device for multicomponent plastics mixtures - has mixing head component discharge ducts connectable by rotary valves to flushing liquid

摘要

Mixing device for multi-component plastics mixtures based on isocyanats has a mixing head provided with a mixing chamber. Mixing chamber is preceded by discharged channels (A) for the components, the channels beingon the discharge side of rotary valves. Channels (A) serve as discharge channels for the flushing fluid which is admitted to the channels by the rotary valves. Channels are also cleaned thoroughly at each flushing cycle. Pref. the rotary valves are provided with hollow shafts which in addition to the inlet and outlet openings for the components is provided adjacent the outlet opening with a groove. Groove is arranged such that on setting of the valve to recirculation it interconnects the channel (A) with the supply channel for the flushing agent. Supply channel passes through the wall of the hollow shaft.