Patent ID: 6203305
Filing Date: 2001-03-20
Classification: B29C

Abstract:
A hot-runner coinjection distributor block arrangement comprising:a multitude of hot-runner nozzles each of which can be closed with a needle of a needle closure system, said block arrangement further comprising:a hot-runner plate releasably connected to a head plate, wherein between said plates at least two individual block parts are arranged, a first of said at least two block parts being disposed on a head plate side, and a second of said at least two block parts being disposed on a nozzle side;an intermediate piece positioned between said at least two block parts through which said intermediate piece there is passed at least one feed channel and the needle; andwherein between the first block part on the head plate side and the head plate there is provided a support element arranged axial to the needle of each needle closure system, and further characterised in that the second block part on the nozzle side is slidingly supported on the hot-runner plate and the at least two block parts in the whole distributor block region are displaceable against one another;wherein between said support element and the head plate there is provided at least one spring element which spaces the support element in a cold operating mode from the head plate by a gap width, said gap width corresponding to the thermal expansion of the whole distributor block arrangement in the needle direction in a hot operating mode, wherein said spring element is arranged and dimensioned to exert a contact pressure force which acts parallel to the needle direction and which, in the cold as well as in the hot operating mode, tightly closes abutting surfaces between the hot-runner nozzles and a mould cavity, or between the hot-runner nozzles and said second block part on the nozzle side, or between the at least two block parts and the respective intermediate piece, said spring element having a maximum spring travel stroke which corresponds to the gap width.