Abstract: A plastic hollow preform is drawn through a mold passage formed in a closed mold by applying a generally constant suction to a downstream end of a conduit having an upstream end connected to an output end of the mold passage. A flow cross section of the conduit is varied between its upstream and downstream ends so as to vary a rate at which the preform is drawn through the passage by the suction. The flow cross section is varied by displacing a valve element in the conduit between positions in which it differently blocks flow through the conduit.

Abstract: An extruder head has inner, middle, and outer annular outlets centered on a common axis and immediately adjacent one another, a flow splitter on the axis, first and second inlets axially upstream in an axial flow direction of the splitter, and a third inlet between the splitter and the outlets. A tubular inner passage centered on the axis extends in the direction from the first inlet around the splitter to the outer outlet and a tubular middle passage centered on the axis extends axially in the direction from the second inlet around the splitter to the middle outlet. An outer passage having an upstream portion axially downstream of the splitter extends transversely of the axis. A tubular downstream portion also axially downstream of the splitter extends coaxially around the inner and middle passages from the upstream portion to the outer outlet.

Abstract: A molding system has a slide displaceable parallel to an axis through a relatively long stroke relative to a stationary overhead extruder head, a center support fixed on the slide, and a pair of end supports displaceable axially through relatively short strokes on the slide between inner and outer end positions. A pair of inner mold halves carried on the center support are directed axially oppositely therefrom toward the end supports. Respective outer mold halves carried on the end supports are axially engageable with the respective inner mold halves in the inner positions of the end supports. An end-support drive connected between the slide and the end supports moves the end supports between their end positions and a slide drive connected to the slide moves the slide axially relative to the head. Each of the end-support drives includes a respective motor mounted on the slide.

Abstract: A blow molding machine for producing three-dimensional low-waste articles including at least one horizontally separated blow mold formed of upper and lower half-molds, a device for vertically displacing at least one of the upper and lower half-molds between an open mold position in which the upper half-mold is spaced from the lower half-mold, and a closed mold position in which the upper and lower half-molds engage each other, a device for locking the upper and lower half-molds in the closed position, and a device for pivoting the upper half-mold in the open mold position about a horizontal axis by substantially 90° and/or displacing the upper half mold in a horizontal plane.

Abstract: A molding system has an extruder for concentrically extruding an outer tubular strand having an inner diameter and an inner tubular strand having an outer diameter from respective annular nozzle openings defined between respective inner and outer nozzle walls. The outer strand at least is are of a resin that swells transversely as it issue from the respective nozzle opening. The nozzle walls are positioned such that the outer diameter of the inner strand is substantially smaller than the inner diameter of the outer strand and the inner strand is separated by a space from the outer strand as the strands issue from the respective nozzle openings. An outer wall of the inner strand engages an inner wall of the outer strand at a spacing from the nozzle openings after substantially all swelling of the strands has taken place. A closeable mold has a passage for drawing the strands through the passage by applying suction to a downstream end of the passage.

Abstract: A plastic hollow preform is drawn through a mold passage formed in a closed mold by applying a generally constant suction to a downstream end of a conduit having an upstream end connected to an output end of the mold passage. A flow cross section of the conduit is varied between its upstream and downstream ends so as to vary a rate at which the preform is drawn through the passage by the suction. The flow cross section is varied by displacing a valve element in the conduit between positions in which it differently blocks flow through the conduit.

Abstract: A mold closing apparatus in which two linearly-shiftable mutually juxtaposed yokes carry respective halves of a mold for shaping thermoplastic articles. A linear force generator acts directly on each of the yokes in a line and in line with the direction of shifting movement for selectively drawing the yokes together and displacing them apart. The closing forces are applied symmetrically to both yokes.

Abstract: A blow-molding apparatus has an ionization bar extending along the row of extruded parisons to dissipate electrostatic charge thereon. The ionization bar comprises a conductive strip received in an insulating holder and preferably a copper laminate strip whose longitudinal edge is turned toward the parisons and can be formed with an array of pointed teeth.

Abstract: A method of manufacturing hollow bodies including inserting into spaced mold halves of a blow mold of a blow molding machine plastic hose-shaped blanks at an extrusion station of the blow molding machine and closing the blow mold, displacing the closed blow mold from the extrusion station to a calibration station of the blow molding machine, inserting thereat blow mandrels into respective cavities of the closed blow mold, lifting, after expiration of predetermined blow time, the blow mandrels, together with the blown hollow bodies to an intermediate position and removing the blown hollow bodies from the blow mandrels lifting the blow mandrels to their initial position thereof, and displacing the blow mold from the calibration station to the extrusion station, with the displacing of the blow mold between the extrusion station and the calibration station being effected by displacing the blow mold at a right angle to a connection line of arranged side-by-side cavities of the blow mold.

Abstract: A method and an apparatus for closing the tool of a plastics-processing machine, especially a blow-molding machine, concerns a two-part tool (1, 2) which is supported by two tool mounting plates (3, 4), at least one run drive (5), at least two closure drives (8), and such that the closure drives (8) each have a hydraulic piston-cylinder system with a cylinder (9), a piston (10), and a cylinder rod (11), and such that an inflow (14) and an outflow (15) for hydraulic oil is situated at the cylinder (9). Also, the end of the piston rod (11) has an interlock element (12) which interacts with a counter-piece (13), such that the piston rod (11) does not interlock with the closure piece (13), in order to apply the closure force, until the tool (1, 2) is situated near its closed position.