Injection molding machine with adjustable nozzle length means

Claim 1

In a machine for molding articles of polymeric organic material, said machine comprising a frame, linear clamPing means comprising a fixed portion secured to the frame and moving components for reciprocating linear movement between a closed position and an open position, at least one split mold comprising a mold component having reciprocating linear movement in the same direction as the clamping means, and means for directing pressurized hot organic polymeric plastic material into a mold cavity for conversion into an article removable from the mold at the end of the molding cycle, the improvement which consists of the combination of: a plurality of stacked split molds whereby the closed clamping means applies pressure to a plurality of molds; a manifold system adapted to distribute organic material, said manifold system being secured to a fixed portion of the frame; nozzles extending from the manifold system toward mold components; nozzle seats on selected movable components of the molds, said nozzle seats having orifices, and said nozzle seats being adapted to fit against the tips of the nozzles whereby hot organic plastic material flows through orifices in the nozzle seats for filling a mold cavity during a programmed portion while the molds are closed, said nozzle seats being reciprocatingly retractable from the nozzle tips during the opening of the molds; and adjustable means on each nozzle fitting against a reciprocatingly retractable seat, whereby the length of each such nozzle can be adjusted to assure an appropriate pressure between the nozzle tip and nozzle seat while a mold is closed, notwithstanding operation of the molding machine at different times at temperatures different enough that thermal expansion or contraction of the length of the nozzle throughout such temperature difference could account for troublesomely different pressures between the nozzle tip and nozzle seat in the absence of such nozzle length adjustment means.