Abstract: Apparatus for blow-molding an article curved in three dimensions comprises two horizontally movable mold parts which, when in contact with each other, define a mold cavity curved in three dimensions to match the required article. An extrusion head extrudes a parison of synthetic resin material into the cavity so that it descends towards the lower end thereof. During this process, a first air flow is fed through apertures in a cover and passes through the mold cavity around the outside of the parison to ease the passage of the parison towards the lower end. In addition, a second air flow is fed through a nozzle in the extrusion head into the interior of the parison so as to help it descend and also to prevent its distortion as it moves into the mold cavity. Thereafter, closure members, which are slidable on, but movable independently of, the main mold parts, close off the upper and lower ends of the mold cavity and pinch the parison between them, their movements being controlled by respective actuators.

Abstract: A rotary plastic blow molding machine (10) includes a rotary wheel (14) mounted on a base (12) and having a plurality of mold stations (30) with mold supports (34) that are mounted by inner and outer slide supports (32a,32b) and moved by an operating cam mechanism (56) in association with a lock mechanism (62) and an unlocking cam mechanism (64) to provide blow molding of an extruded parison. The inner and outer slide supports (32a,32b) are preferably aligned radially with respect to the rotational axis of the wheel (14) and the operating cam mechanism preferably includes a pair of gas springs (98) for providing uniform pressure in the closing of the mold supported by the mold supports (34). A mold recompression mechanism (128) removes mold closing pressure from the lock mechanism (62) prior to operation of the unlocking cam mechanism (64) in preparation for mold opening after completion of the blow molding cycle.

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: The parison transporting device includes a straight mold trough formed by pins which are arranged relative to one another in V-shaped configuration when viewed in cross-section and which can be retracted into pneumatic cylinders to open the bottom of the mold trough. The parison transporting device is moved in the tube receiving position in straight fashion below the tube forming head of a blow molding machine to receive a tubular parison. The parison transporting device is subsequently moved to the blow mold. It is moved there over the mold cavity in such a manner that the tubular member inside the mold trough is positioned with successive sections above the mold cavity, the respectively aligning sections of the tubular piece being released by withdrawing pairs of pins and being dropped side by side into the mold cavity.

Abstract: A preform mold assembly for the injection molding of a multi-layer preform for use in the blow molding of container. The preform mold assembly comprises a preform mold having a gate for receiving molten plastic material. The preform mold has a cavity with longitudinal axis and defines an inner surface. A core-pin is situated within the cavity and spaced from said inner surface. A preform cavity is formed between the inner surface of the cavity and the core-pin for receiving molten plastic from the gate. A threadsplit portion is situated within the cavity at a location remote from said gate. The inner surface of the cavity defines a plurality of flutes formed generally parallel to the cavity longitudinal axis and extend longitudinally along the inner surface of the mold to the threadsplit portion.

Abstract: A blow molding apparatus including a clamp for clamping two molds in back-to-back relationship, the clamp having first and second movable, inner platens supporting interior sections of two molds; first and second movable outer platens supporting exterior mold sections facing the interior sections; a positioner to move the inner and outer platens between opened and closed positions; an extrusion means to extrude parisons between mold sections, injectors to inject air into the interior of the parisons; and a platen retainer to resiliently position the inner platens between the outer platens to equalize pressure in the two molds.

Abstract: A die head for extruding an annular body includes a mandrel having a warp portion with a number of segments spaced around the circumference of the mandrel. Heat is selectively flowed to the segments to warp the mandrel and vary the position of a die pin on the end of the mandrel in a die bushing to control the thickness of the extruded body.

Abstract: An extrusion blow mounding control system for controlling parison wall thickness in an extrusion blow moulding machine includes a wall thickness controller for controlling the width of an extrusion die gap defining parison wall thickness within the machine, an interface unit for supplying an input signal to the wall thickness controller dependent on an actual position signal from a position transducer indicative of the actual position of a movable die member delimiting the die gap, and an output for supplying a desired position signal from the wall thickness controller to an electrohydraulic servo valve for controlling the position of the movable die member to provide a desired width of the die gap.

Abstract: In a blow molding process the mold halves are independently controlled and moved so that a parison may be extruded from an extrusion head and then one of two mold halves may be moved toward the parison. The parison may be grasped by a manipulator to manipulate a portion of the parison so as to overlie a second portion of the mold cavity. The mold is then closed and a standard blow molding procedure performed. The process enables production of reduced flash.

Abstract: Compositions, methods, and systems for manufacturing articles, particularly containers and packaging materials, having a highly inorganically filled matrix. Suitable inorganically filled mixtures are prepared by mixing together an organic polymer binder, water, one or more aggregate materials, fibers, and optional admixtures in the correct proportions in order to form an article which has the desired performance criteria. The inorganically filled mixtures are molded to fashion a portion of the mixture into a form stable shape for the desired article. Once the article has obtained form stability, the article is removed from the mold and allowed to harden to gain strength. The articles may have properties substantially similar to articles presently made from traditional materials like paper, paperboard, polystyrene, plastic, or metal. They have especial utility in the mass production of containers, particularly food and beverage containers.

Abstract: A method of controlling a blow molding machine from a completion of production of one product to a start of production of a next product comprises controlling a temperature of a resin within the blow molding machine, controlling an operation of devices from the completion of production of the one product to the start of production of the next product, controlling a sequent transport of some of the devices in predetermined positions, and controlling a change of the resin in accordance with a supply stop thereof and a data on the next product.

Abstract: An accumulator head for a blow molding machine uses an electromechanical drive assembly for the purging and programming functions. The purging actuator of the drive assembly includes a ball screw and nut assembly in which the ball screw is rotated by an electric motor to move the ball nut assembly vertically and operate the plunger of the accumulator. A second ball screw and nut assembly is included in the programming actuator of the drive assembly for moving the mandrel vertically, thereby controlling the size of the die outlet opening of the accumulator. Preferably, the ball screws of the programming and purging actuators are axially aligned with the nut assemblies each carried by a yoke that travels on guide rods. Four support rods are provided to maintain alignment and provide stationary mounting for the respective motors. The structure has sufficient rigidity to supply the force required for the purging operation, but uses no hydraulic actuators.

Abstract: An extrusion head for extruding a polymer into a parison for blow molding and including a die ring and a mandrel. The die ring and mandrel each include a frustoconical portion. One frustoconical portion is shaped over its full length to define an ovalized annular outlet. The frustoconical portion is also shaped over less than its full length with a recess that is rotationally offset from the first and generally located upstream therefrom. The shapings result in the prison being extruded in a controlled manner through the outlet orifice with a predetermined area of increased thickness.

Abstract: An apparatus for manufacturing hollow resin products. The apparatus includes an extruder for extruding a tubular resin material and cutting the material into a parison with a specified length; a blow molding machine having an upper mold and a lower mold which form a cavity of a specified shape inside; and a parison delivering machine for receiving the parison from the extruder and feeding the parison into the cavity of the lower mold. The parison delivering machine includes a conveyer which has parison feeder for feeding a parison longitudinally from an inlet to an outlet, a driver for driving the feeder, and at least four shafts which serve as pivots of three-dimensional movement of the conveyor.

Abstract: In an apparatus for the production of hollow bodies from thermoplastic material by use of extrusion blow molding, having at least two blow molding units and an extrusion system, in an operating cycle each blow molding unit is movable between a receiving position in which the opened blow molding mold receives a preform and at least one other position in which the expanded hollow body is removed from the blow molding mold. Each blow molding unit is firstly moved from a station remote from the removal station in at least one direction into the removal station and opened after reaching the removal station, whereupon the hollow body previously produced in the blow molding mold is removed. The respective blow molding unit is then moved by use of a second movement in another direction, with the blow molding mold open, into the receiving position which is arranged laterally displaced relative to the path of movement along which the blow molding unit is moved into the removal station.

Abstract: A blow molding machine designed as a two station machine (10) has at least one extrusion device (12) and an accumulator head which supplies a tubular thermoplastic parison to two blow molds arranged next to each other and having two horizontally movable blow molding halves. In order to simplify the construction of the machine at reduced space and to achieve a high productivity, the blow molding machine according to the invention has only a three-platen system with three mold mounting plates (22, 24, 26) for clamping the four blow molding halves (14, 16, 18, 20).

Abstract: A blow molding apparatus is provided including a blow mold, an extrusion apparatus, a locator mechanism, and a blow pin. The blow mold has first and second blow mold halves which are engageable and disengageable with one another. The first and second blow mold halves define first and second inner cavities when the mold halves are engaged. The first cavity has a first shape and the second cavity has a second shape which differs from the first shape. The extrusion apparatus has a die head through which a parison is extruded. The locator mechanism is associated with one of the blow mold and the extrusion apparatus for changing the positioning between the blow mold and the die head to allow capture of an extruded parison by the first and second mold halves within a desired one of the first and second inner cavities such that the extruded parison can be formed into an article having substantially the same shape as the desired cavity.

Abstract: A blow molding apparatus is provided including a blow mold, an extrusion apparatus, a locator mechanism, and a blow pin. The blow mold has first and second blow mold halves which are engageable and disengageable with one another. The first and second blow mold halves define first and second inner cavities when the mold halves are engaged. The first cavity has a first shape and the second cavity has a second shape which differs from the first shape. The extrusion apparatus has a die head through which a parison is extruded. The locator mechanism is associated with one of the blow mold and the extrusion apparatus for changing the positioning between the blow mold and the die head to allow capture of an extruded parison by the first and second mold halves within a desired one of the first and second inner cavities such that the extruded parison can be formed into an article having substantially the same shape as the desired cavity.

Abstract: A blow molding apparatus including a clamp for clamping two molds in fixed, back-to-back relationship, the clamp having a central platen supporting interior sections of two molds in a fixed, back-to-back relationship, and first and second movable platens supporting exterior mold sections facing the interior sections. The apparatus also includes a clamp positioner to move the movable platens between opened and closed positions, an extruder to extrude parisons between mold sections, injectors to inject air into the interior of the parisons, and a central platen retainer to resiliently position the central platen between the movable platens.

Abstract: A die for a blow molding machine has at least one circumferential rectangular cutout section contiguous with the die exit in at least the die ring or the mandrel. The rectangular cutout section expands the material flow channel between the die ring and the mandrel to increase the volume flow of material passing through the die exit at the rectangular cutout section. However, the constant length of the rectangular cutout section in a longitudinal direction maintains a constant linear velocity of material flowing through the die exit.

Abstract: An apparatus for forming a hollow article, wherein all the operations such as shifting and opening/closing of a die are performed by electric actuators such as motors which operate in accordance with a program operation, thus improving the quality of the hollow article as the product. A parison extruded from an extruder is introduced into and held in a die which has been opened by the operation of a die compacting motor. A crosshead associated with the extruder is lifted to draw the parison, and a parison cutting motor operates to cut the drawn parison. Thus, fully automatic production is realized, to ensure high yield of the product.

Abstract: To avoid any displacement of the heavy extruder with the blow head or of the heavy mold closing support with blow mold in three planes that are perpendicular to one another, which displacement has so far been necessary in the production of multiaxial hollow plastic articles, such as curved tubular pieces, the invention suggests the provision of a movable premold or intermediate mold which is matched to the shape of the mold cavity of the blow mold and includes a mold trough which is open at the blow head side, namely between the tube or blow head and the blowing station including a blow mold with a horizontal parting plane, the premold being at least displaceable in the tube receiving position below blow head in two directions (X and Y axes) which are horizontal relative to one another, and being adapted to be lifted and lowered (in the Z axis) and the bottom of said premold being movable over the cavity of a mold part for releasing the parison, e.g., in that the premold bottom consists of one or more doors.

Abstract: A hollow plastic container including a coextruded translucent plastic outer layer, an opaque plastic inner layer, and a viewing stripe of translucent or clear plastic material extending longitudinally in the inner layer. In one form the container viewing stripe is in the inner layer made of clear plastic material placed behind a thin translucent layer. In another form, the stripe is made of the same translucent plastic material as the outer layer. In a further form an additional inner layer is provided of translucent or clear plastic material. The hollow plastic container is made by coextruding a parison of at least two plastic layers to form an outer translucent plastic layer and an inner opaque plastic layer, and simultaneously coextruding a viewing stripe in the inner layer and extending longitudinally of the parison. This method allows production of a distinct viewing stripe of the same nominal outside color of an otherwide opaque plastic container.

Abstract: The invention relates to a storage head for a blow moulding machine for discontinuous manufacture of multi-layer co-extruded and blow-moulded hollow bodies made of thermoplastic. To improve the product quality and to increase the throughput, each distributor element is designed as a spiral channel distributor (20) which distributes the individual molten plastic streams uniformly at the periphery. The ejector (14) consists of at least two concentric tubular pieces (42, 44) and the peripherally distributed plastic flows from the ejector (14) through an annular gap (46) into the storage space (16) in the storage head housing (10) below the ejector.

Abstract: A method for blow molding a hollow body from thermoplastic material, including the steps of providing a blowing nozzle with a mechanical device for stirring. A thermoplastic parison is located within a mold. At least one pressurized gas is injected through the blowing nozzle and into a portion of the thermoplastic parison. A hollow body is formed. The hollow body contains the at least one pressurized gas. The mechanical device continuously stirs to forcible agitate the at least one pressurized gas contained within the hollow body.

Abstract: An injection molding one-piece gate and cavity insert to be mounted between a heated nozzle and a cavity. The insert has a cooling fluid chamber extending around the central gate with a thin cavity wall portion extending between the cooling fluid chamber and a convex portion of the cavity. Alternating frontwardly and rearwardly projecting rib portions extend radially into the cooling fluid chamber to form a pair of tortuous passages between them for cooling fluid flowing each way around the insert from an inlet to an outlet. In addition to providing more cooling because of turbulent flow of the cooling fluid and their increased surface area, these rib portions also substantially increase the strength of the insert to withstand repetitive injection pressure in the cavity.

Abstract: In that process for the production of hollow bodies from thermoplastic material by extrusion blow molding in which discontinuously extruded preforms are expanded in a blow molding mold, at least during that part of the filling phase which is typical of such a process, for an extrusion head, the distance covered by an ejection piston associated with a storage chamber and the speed at which the ejection piston is displaced within the storage chamber by the plasticised material are detected and compared by a central control and regulating device to the respective reference values. On the basis of the result of the comparison operation at least one operating parameter of the process, for example the delivery output of the extruder or the extent of the emptying strike movement of the ejection piston can then be adapted while still in the same working cycle in such a way that substantially the required preform volume is ejected.

Abstract: A travelling mold tunnel for forming double walled corrugated tube has a first portion for forming corrugated tube and a second belled portion for forming a cuff portion suitable for coupling with another tube. At the upstream end of the belled portion, radial small diameter passages are provided so that a pressure differential may be set up between the inside and the outside of a first parison within the belled portion. Thus, vacuum may be applied through the radial passages to allow an inner parison to laminate with the first parison over its inner surface in the belled portion. The first parison is drawn into the passages in protruding balloons. These may be ruptured. Alternatively, positive pressure may be used. In this case, the balloons may be ruptured inwardly.

Abstract: A machine for the manufacture of hollow plastic pieces with several axes located at angles to each other in a three dimensional sense, which includes mold halves for forming a mold chamber, wherein the mold halves are supported so that at least one of them is moved into and out of contact with the other, at an angle between 40.degree. and 60.degree., and preferably about 45.degree.

Abstract: A parison length control method for a blow molding machine in which a parison is extruded vertically, the end of the parison is closed, and a blowing gas is blown into the closed parison. The method includes the step of deriving a relationship between parison length and extruder screw rotation speed during a test molding process. Current parison length is then detected during normal molding operation, and the difference between the current parison length and a target parison length is derived. The extruder screw rotation speed is then controlled by calculating a correction amount for the extruder screw rotation speed based on the parison length difference in combination with the relationship between parison length and extruder screw rotation speed. The extruder screw rotation speed is then adjusted by the correction amount so as to attain the target parison length.

Abstract: An apparatus for the manufacture of pipes having transverse profile features has a machine bed, on which half shells, which can be combined to form a mold, are rotatably and displaceably drivable. The half shells are pressed together on a molding path by guide rails, of which one is displaceable at right angles to the direction of production by hydraulically actuatable drives. Interlockings may be provided in addition, a locking member of which engaging with an associated locking recess.

Abstract: Apparatus for forming a lightweight plastic bottle having a body and an integral handle includes pre-blowing a tubular parison positioned between partible blow mold sections, closing the blow mold sections to compression mold the handle and blowing the parison to form the body integral with the handle and a line of juncture between the body and the handle.

Abstract: An extrusion head for a blow molding machine wherein a movable plunger is slidably mounted in a distributor head which receives a melt at an inlet end of its channel and directs it along such channel to the terminal end of the channel while simultaneously directing portions of it along spiral radial paths to the lower circumferential edge of the distributor head to fill an accumulator chamber which also causes the plunger to recede facilitating the filling of the accumulator chamber. The channel as defined by the adjacent circumferential wall and the curvilinear contour on the distributor head defines a smooth integral flow channel that is curvilinear in cross section.

Abstract: An extrusion blow molding apparatus for making hollow plastic articles includes a machine frame with an extruder horizontally received in the machine frame and having a nozzle head for vertically extruding a parison at one end face of the machine frame. A pair of split blow molds is disposed at this end face of the machine frame bilaterally underneath the nozzle head, with each blow mold cooperating with a blow mandrel secured to the machine frame above the blow mold. The extruder together with its drive and supply lines and at least one of the blow mandrels are detachably received in the machine frame so as to allow a positional exchange therebetween for allowing blow molding of round plastic articles as well as flat plastic articles.

Abstract: A parison controller of blow molding apparatus for varying the thickness of a parison extruded from an ejection orifice by displacing in an up and down direction a core provided at the ejection orifice of the die of a cross head. The parison controller of blow molding apparatus has a motor through which the core is displaced. It further includes: a rod connected to the core provided at the cross head; a female threaded portion formed on the upper portion of the rod; a rotating rod having a male threaded portion threaded into said female threaded portion; a reduction gear connected to said rotating rod through a thrust bearing; and the motor connected to the reduction gear. Since the core forming the ejection orifice for ejecting the parison is displaced through a motor, a reduction in the size thereof and saving of resources may be achieved and a high quality parison may be obtained as compared with a conventional parison controller which uses a hydraulic system.

Abstract: An apparatus for manufacturing a tube-like preform having a longitudinal wall with a variable cross-section for blow molding of a hollow body from a thermoplastic material, includes a tubular die having a variable exit opening, and a collar die having a recess and movable into engagement with and away from the tubular die, the preform being produced by ejecting of the thermoplastic material from the exit opening of the tubular die into the recess of the collar die while moving tubular die, with controlling a speed of movement of the collar die and a cross-section of the exit opening of the tubular die in such a manner that larger and smaller cross-section of the exit opening correspond to speed rate of the collar die, so that a thickness of the wall of the producible preform changes from peaks to valleys in a wave-like manner to form the variable cross-section of the wall.

Abstract: For the continuous manufacture of a compound pipe with a pipe socket including a smooth internal tube and an external tube provided with transverse grooves and welded together with the latter, an external tube and an internal tube are extruded, the latter into the external tube. While the normal compound pipe is manufactured, gas is blown at a slight overpressure into the space beteen the external tube and the internal tube. When the pipe socket is produced, this space is vented so that a full-surface bearing of the internal tube against the external tube is achieved, to which end the internal tube is acted upon from its inside by gas under pressure.

Abstract: An apparatus for manufacturing a hollow synthetic resin product, including a movable parison guide and a movable lower molding portion which align an extruding head, the parison guide and an end of the lower molding portion in a perpendicular plane. The lower molding portion is moved in a direction perpendicular to the perpendicular plane while a parison is extruded from the extruding head, while the parison guide is moved in a direction crossing the moving direction of the lower molding portion in accordance with a shape of a groove of the lower molding portion to accommodate a first portion of the parison in the groove. A cutter cuts the parison in a predetermined length when the predetermined length thereof is extruded, while a parison pinch holds a portion of the parison to be cut immediately before the parison is cut.

Abstract: A plastics processing machine, in particular a blow moulding machine, with mould halves of a first product mould secured to movable mould clamping plates, and separate mould halves of a second product mould clamped onto the mould halves of the first product mould. The machine is operated with the mould halves of the first product mould to produce a first product line. During this operation, the mould halves for the second product mould are removed. The machine is operated with the mould halves for the second product line by attaching these mould halves to the mould halves of the first product mould.

Abstract: An extrusion head for a blow molding machine wherein a movable plunger is slidably mounted in a distributor head which receives a melt at an inlet end of its channel and directs it along such channel to the terminal end of the channel while simultaneously directing portions of it along spiral radial paths to the lower circumferential edge of the distributor head to fill an accumulator chamber which also causes the plunger to recede facilitating the filling of the accumulator chamber. The channel as defined by the adjacent circumferential wall and the curvilinear contour on the distributor head defines a smooth integral flow channel that is curvilinear in cross section.

Abstract: A blow molding die includes a housing, and a mandrel with a core integrated therewith, combined to form a vertically extending annular melt passage communicating with a hole formed at its top portion for feeding a plasticized resin melt from an extruder, and terminating at die lips formed at its free bottom end. The mandrel has a pair or grooves symmetrical relative to its axis, formed at its peripheral surface so as to have hanger type profiles in its front developed view, and connecting to each other at lower ends thereof. The feed hole opens to the symmetrical hanger type grooves at top and central points thereof. Each groove has an arced surface and a cross-sectional area decreasing in a direction from the top and central point to the lower end.

Abstract: An improved injection blow molding machine has an melt accumulator or melt metering chamber and a vertically extending oval type die communicating therewith for injecting an elliptical annular parison through the die, which is to be blow molded to produce a hollow double wall type article. The oval type die includes a die housing and a mandrel mounted therein to define a melt passage therebetween having a die lip or opening of a four sided elliptical annular profile at a free lower end of the die. The accumulator is in direct contact with the mandrel, and/or the die housing is enlarged in a horizontal direction at a lower end portion thereof. Preferably the enlarged lower end portion is formed by a plate part fixed to a block part forming an upper portion of the die housing.

Abstract: A method and apparatus for injecting and mold clamping control of an injection blow molding machine, wherein a parison injected downward from a die between mold halves defining a cavity is detected to thereby determine the dynamic locus of its free end. In every run the mold clamping is commanded to start before the end of injection is commanded and is effected according to the clamping operational conditions determined based on the parison locus determined in the instant or preceding run. In one method a clamping starting time is determined by a calculation with a predetermined clamping stroke speed. In another alternative method an initial clamping stroke speed is determined by a calculation with a predetermined clamping starting time and following stroke speed.

Abstract: The method includes moving a parison guide and a lower molding portion to substantially vertically align an extruding head, the parison guide and an end of the lower molding portion. Then, the lower molding portion is moved substantially horizontally while extruding a parison from the extruding head, while the parison guide is moved laterally in a direction crossing the moving direction of the lower molding portion in accordance with a shape of a groove of the lower molding portion to accommodate a first portion of the parison in the groove. Subsequently, the parison is cut into a predetermined length when the predetermined length thereof is extruded, while a portion of the parison to be cut is held by a parison pinch.

Abstract: A plastic system for extruding injection molding and extruding a hollow tube from plastic containing heat sensitive material for thereafter forming into a plastic container by blowing including an extruder for melting the plastic and delivering it to an injection system for injecting the plastic into a manifold that delivers the plastic to the tubular cavities of an injection head including providing a static mixer adjacent each of the cavities. By such an arrangement, the plastic flow in each flow channel provides a uniform homogeneous plastic material such that streaks which may be caused by degraded plastic material or by different color material from a previous run are eliminated.

Abstract: The invention relates to a storage head for a blow moulding machine for discontinuous manufacture of multi-layer co-extruded and blow-moulded hollow bodies made of thermoplastic. To improve the product quality and to increase the throughput, each distributor element is designed as a spiral channel distributor (20) which distributes the individual molten plastic streams uniformly at the periphery. The ejector (14) consists of at least two concentric tubular pieces (42, 44, 46) and the peripherally distributed plastic streams issue from the front face of the ejector (14) and unite to form a single multi-layer flexible plastic tube in the storage space (16) in the storage head housing (10) below the ejector.

Abstract: The invention relates to a storage head for a blow moulding machine for discontinuous manufacture of multi-layer co-extruded and blow-moulded hollow bodies made of thermoplastic. To improve the product quality and to increase the throughput, each distributor element is designed as a spiral channel distributor (20) which distributes the individual molten plastic streams uniformly at the periphery. The ejector (14) consists of at least two concentric tubular pieces (42, 44) and the peripherally distributed plastic flows from the ejector (14) through an annular gap (46) into the storage space (16) in the storage head housing (10) below the ejector.

Abstract: A process and apparatus for the production of hollow bodies from thermoplastic material by means of blow molding uses a blow molding mold which includes at least first and second mold portions to enclose a generally tubular extruded preform which is expanded within the mold under the effect of an increased internal pressure within the preform. To provide for asymmetric closing and/or opening movements of the mold portions relative to the preform, the blow molding mold is displaced as an entirety parallel to the direction of the opening and/or closing movements of the mold portions, more especially during the mold closing and/or opening procedure, so that an additional motion is superimposed on the movements of the mold portions.

Abstract: The invention resides in a rotary blow molding machine in which under an extruder for extruding a parison, a turntable is arranged which has plural sets of molds mounted thereon for holding the parison therebetween and blow-molding the parison, the turntable is rotated by a motor, an annular driven gear is provided on the turntable, and one pair of idle gears are made to intervene between the driven gear and a driving gear for transmitting the rotation of the motor so as to intermesh with both the gears.

Abstract: In general, used thermoplastic liquid containers such as oil and solvent bottles are discarded. When recycling oil bottles, the usual practice is to wash the bottles with a solvent to remove oil therefrom. Washing of the bottles results in large quantities of used, oil-containing solvent, which present a disposal problem. A simple solution to the problem of recycling liquid containers with no preliminary washing or cleaning operation includes the steps of tumbling the bottles to promote liquid separation, shredding the bottles into small pieces and draining the liquid therefrom, grinding the pieces of plastic to yield a particulate thermoplastic, and mixing the particulate thermoplastic and any liquid remaining therein with an additive, e.g. an oil absorbent and a filler such as calcium carbonate, glass, mica or talc, and when the liquid is an oil, an absorbent to produce an extrudable mixture which can be used to form new containers.