Abstract: A tool closing system for plastic blow molding machines comprises a drive base plate, a front mold clamping plate and a rear mold clamping plate positioned between the front clamping plate and the base plate. The base plate, front clamping plate, and rear clamping plate are shiftably arranged on guides which are mounted on a carriage. A drive device is fastened to the base plate and comprises an extensible and retractable drive rod which is articulated to the rear clamping plate for force transmission without bending moment. Two substantially C-shaped or U-shaped frame elements are arranged side by side in parallel with the guides. Each have a substantially horizontally extending central web and two substantially vertically extending webs. A respective one of the two vertical webs is articulated to the base plate and the other vertical web is articulated to the front clamping plate.

Abstract: The blow molding machine is characterized in that that the preferably two closing units can be reciprocated along a first guide path extending in a direction transverse to a second guide path which extends from a central removal position of the first guide path to the insertion device, the lower closing plates with the lower mold halves of the two closing units being alternately movable on the second guide path from the removal position to the insertion device and back. The blow molding machine is characterized by an improved mode of operation.

Abstract: In a blow molding machine comprising a preform station having arranged thereon at least one extruder including at least one downstream parison head, comprising at least one blowing station on which a blowing device is arranged with at least one blowing and calibrating mandrel, and at least one mold system having a blow mold arranged underneath the at least one parison head to accommodate the thermally plasticated parison extruded out of the at least one parison head between the opened mold halves, the blow mold being moved into the blowing station after the mold halves have been closed, wherein the blowing station is arranged in front of the preform station and in parallel with the mold system.

Abstract: Each of the clamping plates of the closing unit of the blow molding machine has secured thereto a pivotable locking means which in the calibration position in the swung-up state comes into engagement with a plate which is part of the calibration device. A short friction-type connection which is symmetrical relative to the mold parting plane is thereby established between the blow mold and the calibration cylinder during calibration so that the calibration forces are transmitted in an exact manner. The locking means swing downwards when the blow mold is opened and/or the closing unit returns to the head station. Collisions with other machine parts are thereby ruled out.

Abstract: Each of the clamping plates of the closing unit of the blow molding machine has secured thereto a pivotable locking means which in the calibration position in the swung-up state comes into engagement with a plate which is part of the calibration device. A short friction-type connection which is symmetrical relative to the mold parting plane is thereby established between the blow mold and the calibration cylinder during calibration so that the calibration forces are transmitted in an exact manner. The locking means swing downwards when the blow mold is opened and/or the closing unit returns to the head station. Collisions with other machine parts are thereby ruled out.

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 blow-molding machine for producing hollow plastic articles comprises a blow mold having a plurality of cavities corresponding to the shape and dimension of the finished hollow articles. The blow mold has at least two closely adjacent and separate blow molds and an opening and closing system operatively associated with each blow mold. The machine is provided with a tube station and a blow station. The tube station has a plurality of tube-shaped parison-forming heads located parallel to and next to each other for filling each cavity with a parison. The number of cavities corresponds to the number of parisons. The blow station is offset relative to the tube station and thereat the parisons in closed blow molds are inflated to the finished hollow articles. A joint transportation system for moving all of said blow molds between the tube station and the blow station is provided.

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: A coextrusion head for the continuous production of multilayer tubular structures having three to seven-layers. The basic tubular structure produced has a central barrier layer and symmetrically arranged thereabout, layers of adhesive agent, regenerated and/or carrier materials. The upper portion of the coextrusion head contains a multipiece jacket that defines annular passages in which the layers of the structure are formed. The lower portion contains the nozzle from which the tubular structure is extruded. Between the upper and lower portions are placed a core ring and a nozzle ring which together provide the transport channel between the annular passageway in which the layers are joined and the inlet to the nozzle. Each ring has two alternative configurations. One configuration permits movement of the layered material in the annular passageway where the layers are joined and the second configuration precludes such movement.

Abstract: Accumulating heads to produce preliminary blanks for the production of hollow plastic articles such as containers by the blow process (known as the "joint extrusion process"), such blanks, being of cylindrical "tube" configuration and also laminates which are layers of different material. Suitable accumulating tube heads for the joint extrusion process are disclosed wherein the layers retain their relative positions and thickness ratios over their entire length up until expelled from the nozzle. The accumulating heads each have a plurality of coaxial annular feed passages, each fed from a different extruder, which open into an annular space and passage. The annular passage is located between the facing walls of concentric inner and outer packing washers.

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.

Abstract: An extruder head wherein the housing for a mandrel has a lateral inlet for admission of plasticized material into an arcuate bore of the mandrel and the mandrel has two divergent connecting passages which cause the plasticized material to form a first tubular stream with two radial seams at the inner end of an elongated annular chamber which is defined by the housing and mandrel and wherein the material flows toward an extrusion orifice. The inner end of the chamber contains a ring which divides the first stream into two discrete streams one of which flows along a neck portion of the mandrel and the other of which flows around the ring. The two discrete streams merge into a fourth tubular stream downstream of the ring. The periphery of the ring and/or the neck portion of the mandrel has inclined baffles which subdivide the respective discrete stream into several fields whose boundaries at the downstream end of the ring are out of alinement with the seams of the other discrete stream.

Abstract: A mutli-stage blowmolding apparatus wherein a carriage is reciprocable between first and second positions and supports two open-and-shut molds which are operable independently of each other. In the first position of the carriage, one of the molds receives a parison which is being extruded from the nozzle of an extruder while the other of the molds receives a preform which is suspended on the blowing mandrel of a first blowing unit. The mandrel is withdrawn before the one mold closes around a freshly extruded parison and the carriage is immediately moved to the second position in which the parison in the cavity of the one mold is in register with the first blowing unit and can be expanded by the blowing mandrel to be thereby converted into a preform. At the same time, the preform in the other mold registers with the blowing mandrel of a second blowing unit which converts the preform into a bottle or another hollow shaped article.