Abstract: An injection gate of a mold cavity comprises an elongate valve rod which passes axially through a flow channel for molten plastic material and is guided in an extension of a thin-walled steel cylinder open at its opposite end toward an adjoining manifold plate. The rod extremity remote from the gate is secured to a tubular neck of a piston inside the cylinder whose stroke length is a fraction of the axial height of the cylinder's interior, a clearance around this neck providing space for drooling plastic while the length of the neck and of the peripheral cylinder wall serves for thermally insulating the manifold plate from the flow channel.

Abstract: Preforms or parisons to be blow-molded into bottles are produced in cavities of a lower mold half of a vertical injection-molding machine with the aid of respective cores depending into these cavities from an upper mold half when the mold is closed. As the two mold halves separate, the parisons adhere to the respective cores from which they are subsequently discharged into respective nests of a transfer box or respective cells of a blow-molding unit interposed between these mold halves. In the first instance, the parisons are cooled by a circulating air stream while the transfer box is laterally withdrawn before the start of a new injection-molding cycle, the rigidified parisons being then released from their nests to drop into pockets of an underlying conveyor transporting them to a blow-molding station. In the second instance, the cores are hollow and descend with their parisons into the blow-molding cells whose split walls are closed around the cores by fluidic or mechanical means.

Abstract: A take-off plate, mounted near one of two relatively movable mold portions and insertable therebetween to remove freshly molded workpieces, enters a slot of a guide block rigid with the same mold portion upon moving from a retracted to an inserted position, the guide block also having a bore intersecting the slot and extending in the direction of mold motion. A pin on the other mold portion traverses the bore upon closure of the mold to prevent untimely insertion of the take-off plate; conversely, the take-off plate in its inserted position obstructs the bore to prevent premature mold closure.

Abstract: An apparatus for injection molding composite articles from two materials includes a rotary mold block carrying a two material mold half between a first material mold half and a second material mold half; the rotary block providing, in sequence, a first material mold cavity and a composite material mold cavity in which latter cavity the second material is injected over, and preferably in positive engagement with, the first material. Core pins are carried in the rotary block which includes means to index the pins for providing core areas in the first material and subsequently retracting the pins so that the second material can flow into the core areas for positive engagement of the composite molded materials.

Abstract: A thrust member on column secured to a movable platen of an injection-molding machine, surrounded by a mounting frame with laterally withdrawable shutters which enter behind the thrust member in the terminal phase of a mold-closing stroke for transmitting to the thrust member a supplemental clamping force, is linked with a hydraulically actuated plunger or driving piston via a lost-motion coupling. The clamping force is supplied through one or more annular pistons received in respective cylinder chambers of a stationary housing linked via tie rods with a fixed platen. Upon the release of the clamping force, a counter-vailing hydraulic force is developed between the column and the driving piston, whose forward displacement is limited by a fixed abutment, to break open the mold with a larger hydraulic force.

Abstract: Preforms or parisons to be blow-molded into bottles are produced in cavities of a lower mold half of a vertical injection-molding machine with the aid of respective cores depending into these cavities from an upper mold half when the mold is closed. As the two mold halves separate, the parisons adhere to the respective cores from which they are subsequently discharged into respective nests of a transfer box or respective cells of a blow-molding unit interposed between these mold halves. In the first instance, the parisons are cooled by a circulating air stream while the transfer box is laterally withdrawn before the start of a new injection-molding cycle, the rigidified parisons being then released from their nests to drop into pockets of an underlying conveyor transporting them to a blow-molding station. In the second instance, the cores are hollow and descend with their parisons into the blow-molding cells whose split walls are closed around the cores by fluidic or mechanical means.

Abstract: A vertical injection-molding machine with two overlappingly operating injection molds produces two sets of eight parisons each in staggered operating cycles. Each set of parisons is transferred by a respective carrier assembly, immediately upon the opening of the respective injection mold, into the vicinity of a blow-molding unit with eight cells in which the parisons are inflated into bottles during half an injection cycle. The transfer from the closely spaced injection cavities to the blow-molding unit is performed by several carriers moving over laterally diverging tracks whereby the parisons arrive at the blow-molding unit in pockets of these carriers already separated to the extent necessary for joint introduction into the eight-cell blow mold.

Abstract: A central chamber of a mold body, communicating through a heated nozzle with a supply channel, has a plurality of peripherally spaced injection orifices opening into respective cavities for the molding of tubular articles such as shells of disposable syringes, each cavity being defined by a generally cylindrical recess in the mold body paralleling the nozzle axis and a core received with all-around clearance in that recess. Each cavity has two elongate sections of larger and smaller diameter interconnected by a wider annular gap at the level of the injection orifices; the axial width of the annular gap progressively diminishes with increasing distance from the corresponding orifice.

Abstract: An injection gate of a mold cavity comprises an elongate valve rod which passes axially through a flow channel for molten plastic material and is guided in an extension of a thin-walled steel cylinder open at its opposite end toward an adjoining manifold plate. The rod extremity remote from the gate is secured to a tubular neck of a piston inside the cylinder whose stroke length is a fraction of the axial height of the cylinder's interior, a clearance around this neck providing space for drooling plastic while the length of the neck and of the peripheral cylinder wall serves for thermally insulating the manifold plate from the flow channel.

Abstract: A mold with two relatively movable portions, one of them having one or more shallow cavities for the production of substantially flat articles, is provided with lateral guide elements which, upon separation of the two mold portions by a distance exceeding but slightly the depth of these cavities, define with the separated mold portions a vertical channel through which the ejected articles descend with a predetermined orientation onto an underlying conveyor or other receiver therefore. The guide elements may be retractable into the mold portion on which they are supported, or partly receivable in the opposite mold portion when the mold is closed. Some of the guide elements could be extensions of ejectors serving to dislodge a molded article from its cavity.

Abstract: Heated material is injected into an annular cavity, defined by a pair of mold-halves, through a sprue passage, defined by a sprue bushing and an end portion of a punch. The annular cavity and the sprue passage form, respectively, the centrally apertured part and a sprue. After partial cooling of the heated material, the punch is locked in place while the annular cavity is displaced relative to the sprue passage so that the sprue is severed from the part along the peripheral surface of the punch end portion. The mold halves are separated to open the annular cavity while the sprue is resting on the punch end portion, and while the part is held by the punch end peripheral surface. After the mold halves are separated, a sprue ejector member and a part ejector member are actuated to eject, respectively, the sprue and the part from the punch end portion.

Abstract: A clamping mechanism, effective to press a movable platen against a fixed platen in a terminal phase of a mold-closing stroke of an injection-molding machine, comprises a series of coaxial annular pistons received with progressively larger clearances in respective inner peripheral grooves of a stationary housing linked by tie rods with the fixed platen. The pistons, which can be interconnected by elastic bolts, bear upon a mounting frame, slidable along the tie rods, supporting a pair of laterally withdrawable shutters which in their retracted position give passage to a tubular thrust member coaxially surrounding a plunger secured to that thrust member and to the movable platen. The opposite end of the plunger carries a piston head received, within the housing, in a central driving cylinder to which hydraulic fluid can be admitted from either end for advancing or retracting the movable platen in a mold-closing or a mold-opening stroke.

Abstract: Heated material is injected into an annular cavity, defined by a pair of mold-halves, through a sprue passage, defined by a sprue bushing and an end portion of a punch. The annular cavity and the sprue passage form, respectively, the centrally apertured part and a sprue. After partial cooling of the heated material, the punch is locked in place while the annular cavity is displaced relative to the sprue passage so that the sprue is severed from the part along the peripheral surface of the punch end portion. The mold halves are separated to open the annular cavity while the sprue is resting on the punch end portion, and while the part is held by the punch end peripheral surface. After the mold halves are separated, a sprue ejector member and a part ejector member are actuated to eject, respectively, the sprue and the part from the punch end portion.

Abstract: An injection-molding machine with a set of stacked mold plates, defining several axially spaced mold cavities therebetween, includes an injection unit with one or more nozzles movable perpendicularly to the stack for contact with respective inlets, leading to the several cavities, which are aligned with these nozzles in the closed position of the multiple mold. The mold plates may be interconnected by a lazytong linkage or by lost-motion couplings for proper relative spacing in the open mold position.

Abstract: A conveyor mechanism including two belts carries two types of interfitting molded articles such as cups and lids from a molding machine to an assembly station, maintaining a constant orientation between them. The assembly station comprises a pair of synchronized and overlapping star wheels, counterrotated by a Geneva drive, which remove the molded articles from the conveyor belts, bring them into vertical alignment, and come to a momentary stop in this position in which a plunger synchronized with the Geneva motion of the star wheels joins the two parts together and pushes them into an overlying stacker tube, whereupon the star wheels resume their motion. Several stacker tubes, linked by an endless transport chain, are capable of receiving a limited number of pairs of molded articles, their drive mechanism being so coupled with the star-wheel drive as to advance the chain to bring a loaded stacker tube to an unloading station whenever a preceding tube in the array has been filled.