Abstract: To be able to guide the parisons in a reheat type blow molding machine having separate heat and blow paths along the path where they are heated up to blow temperature, i.e.

Abstract: A process and apparatus for heating injected, cold preform blanks composed of partly crystalline synthetic resins which have been produced by injection molding. The preform blanks are positioned in holders on a conveyor and are rotated about their longitudinal axes as they are moved along the conveyor, heated to blow mold temperature in multiple stages including a series of heating and cooling stations on respective opposite sides of the conveyor so as to be heated from one side of the conveyor and cooled from the other side while being carried on the conveyor and while being simultaneously rotated whereby they are uniformally heated across their cross sections. The process is completed by tempering and producing a protective surface on the preform blanks before they are supplied to a blow molding device. The entire process requires only several minutes of time.

Abstract: A process and apparatus for heating injected, cold preform blanks to blow molding temperature on a conveyor path wherein they are thereafter fed to a blow mold, the preform blanks being first heated to a temperature below the blow moulding temperature, then cooled and later reheated to a temperature slightly above the blow molding temperature, whereupon the preform blanks are allowed to equalize in temperature inside and out or are caused to do so by slightly cooling their outsides. The spacing on the holders on the conveyor chain, on which are mounted the preform blanks, is selectively adjustable to avoid heat radiation losses. The neck portions of the mounted preform blanks are surrounded completely by protective sheathings so that such neck portions are not heated while being conveyed to the blow mold.

Abstract: Thermoplastic pre-forms which are obtained as a result of expansion of parisons in a pre-form blow mold are transformed into bottles or analogous hollow shaped articles in a final blow mold. The first stage of transformation involves mechanical stretching of the pre-form in the cavity of the final mold simultaneously with or prior to admission of a compressed blowing fluid to expand the major portion of the pre-form into contact with the adjacent surface of the final mold. The next stage involves admission of the blowing medium at a higher pressure to effect abrupt biaxial expansion of the closed end and of the portion intermediate the closed end and the major portion into contact with the adjacent surfaces of the final mold.