Abstract: The neck finish for a wide range of plastic water dispenser bottles is formed so that it has a smooth, straight inner diameter and is fully calibrated, not requiring any post trimming. The parison is extruded over a fixed blow pin, which also serves as an inner mandrel. The wall thickness of the parison is controlled to provide the desired amount of material to fill the neck area and compression mold the neck body. When the mold is closed on the parison, the area between the cutting ring and striker plate comes into contact to form a calibrated neck finish. The blow pin tip is completely water cooled to the upper end and includes a specially positioned orifices adjacent the end to distribute the blow air so that it spreads out material, thereby reducing material push out and also cools the lower neck area. The assembly is designed to be very rigid, to assist in part de-molding.

Abstract: The invention is directed to a bi-directional check ring for a two-stage injection unit. More specifically, a close fitting ring is inserted behind the plunger head of the melt accumulator so that normal running clearances between the plunger and barrel bore can be used. The outer diameter of this check ring has a very close fit with the inner diameter the injection barrel, but is not rigidly connected to the plunger. Accordingly, the plunger is free to “floats” while injection and plastication/filling take place. The open volume between the ring and plunger is small, but sufficient to permit the ring to “float” very close to the barrel inner diameter, without being influenced by the alignment of the plunger and injection drive motor.

Abstract: A method for cascade, closed loop control of multiple operating parameters for an extrusion blow molding machine having multiple accumulators is disclosed. The method provides closed loop control of the ram back pressure during refill, along with the closed loop adjustment of the pressure set points for “slave” accumulators based on a comparison of ram positions with that of a “master” accumulator. For systems that supply each accumulator with a separate extruder, the rotational speed of the extruder screw is the controlled operating parameter during refill. With respect to extrusion of the parisons, there is closed loop control of the ram velocity in conjunction with adjustment of the velocity set points for the slave accumulators based on a comparison of ram positions with that of the master accumulator.

Abstract: An electric-motor-powered drive for providing increased output torque within a predetermined space envelope. A pair of electric motors are disposed in end-to-end relationship with their respective output drive shafts in opposed, coaxial relationship. A coupling member extends between the respective motor output shafts to mechanically couple them together for joint rotation in the same direction of rotation and at the same rotational speed.

Abstract: The accumulator of an extrusion blow molding machine is constructed to include a stroke positioner that comprises inter-engaging, threaded components that enable the piston of the programming cylinder to be adjusted relative to the inner rod of the programming system in the accumulator assembly. Since the inner rod ultimately connects to the die pin, this adjustment directly determines the position at which the piston in the programming cylinder will close off the die gap. In particular, the components of the programming system can be adjusted so that the die gap is closed just as the piston of the programming cylinder reaches the limit of its stroke.

Abstract: An injection molding apparatus capable of producing injection molded articles from at least two plastic melts, includes an additional mold mounting device between a fixed mold mounting plate and a movable mold mounting plate that is traversed along four essentially horizontal tie rods. The additional mold mounting device is also pivotable around a rotational axis aligned perpendicular to the longitudinal axis of the tie rods, and carries additional mold halves that cooperate with the mold halves mounted on the mold mounting plates on at least two side surfaces that are aligned with a spacing parallel to each other and relative to the rotational axis. The additional mold mounting device comprises upper and lower support blocks that are arranged at a spacing relative to each other in an essentially vertically aligned plane, with each support block being guided on at least of the two tie rods. A friction or pivot bearing is provided for vertically aligned pivots of a prismatic mold core support.

Abstract: An electro-mechanical drive apparatus uses a single variable speed motor, two one-way clutches, a hydraulic pump stack and a hydraulic accumulator to provide both hydraulic power for linear motion axes and rotation of a driven element of an electromechanical drive system in an injection molding machine. When engaged, the first one-way clutch couples the drive motor to the pump stack, while the second one-way clutch couples the motor to the driven element. During rotation of the drive motor in a forward direction, (a) the first one-way clutch engages, rotating the shaft of the hydraulic pump stack to power the machine's hydraulic systems and charge an accumulator; and (b) the second one-way clutch slips. When the drive motor is rotated in a reverse direction, (a) the second one-way clutch engages, rotating the driven element, and (b) the first one-way clutch slips.

Abstract: A mold core positioning device includes a cam member carried by a first mold segment that is configured to engage a cam follower carried by a second, cooperating mold segment. The cam follower is provided on a core slide to which an outwardly extending core member, such as a core pin, is connected. The core slide is movable toward and away from a mold cavity to move the core pin into and out of a position within the mold cavity. The cam member includes an extension cam surface and a withdrawal cam surface. The withdrawal cam surface includes a breakaway cam surface that causes slow retraction of the core pin relative to the molded part, and a retraction cam surface that causes more rapid withdrawal of the core slide and core pin after the core pin has been initially separated from the molded part.

Abstract: The invention is directed to a two-stage, all-electric injection unit. More specifically, an injection unit in which the feed screw is preferably used only for plastication and the injection of the plasticized material is accomplished by a separate accumulator having an electrically driven linear actuator, such as a ball screw mechanism. The plunger of the accumulator is configured with a helical flight and is rotatable by way of a one-way clutch interposed between the plunger and the ball screw.

Abstract: A valve for controlling the flow of fluent plastic material from an injection molding machine to a mold cavity. The valve includes an axially slidable valve pin that interacts with a material outlet to control flow through the valve selectively. The valve pin is actuated by an eccentric cam arrangement that positively drives the valve pin between positions where it is engaged with or disengaged from the material outlet. The cam acts on the valve pin only in an axial direction to avoid wear occasioned by side loads imposed on a valve pin.

Abstract: A method and apparatus for verification of the linear position of a machine element driven by a motor is provided. The actual position of the element is detected and compared to an expected position. When the two positions differ from each other by more than a predetermined tolerance value for a predetermined amount of time, an error signal is generated which deactivates the motor and generates an alarm for the machine operator. Preferably, the linear position of the axis is detected by a transducer and the expected position is determined by detecting the rotary position of the motor through the use of a resolver, which is then converted to a linear equivalent through the use of the gearing ratio. The method and apparatus can detect faulty machine conditions and thereby prevent machine malfunction and/or machine damage. Preferably, the method and apparatus are used to verify the position of machine elements in an injection molding machine.

Abstract: A heating device for use in injection molding includes an insulating device that has a wear resistant layer of titanium or a titanium alloy to provide a relatively low coefficient of thermal conductivity; and an insulating layer of mica. The wear resistant layer to be arranged on the inside and/or outside of the insulating layer. Whether the wear resistant layer is arranged on the outside, inside, or both outside and inside, depends on the respective field of application. By the use of the materials titanium/titanium alloy and mica, a heating device with good insulation values can be produced in a very compact construction. Because of its high wear resistance, the heating device will also have a long service life.

Abstract: A method and apparatus for detecting an aberrant velocity of a motor used to drive an element in a plastics processing machine, such as an injection molding machine, for example. The velocity of the motor is detected by a first sensor and a machine parameter associated with the machine operation is provided. A velocity limit is determined based upon the machine parameter and an error signal is generated when the motor velocity exceeds the velocity limit by more than a predetermined tolerance value. Preferably, the machine parameter comprises the position of the element driven by the motor, which is sensed by a sensor, such as a linear displacement transducer. The velocity limit can be based upon this measured element position as well as data entered for the particular machine, such as a minimum element position, a maximum element position, and a maximum motor velocity, such that a desired motor operating envelope is defined.

Abstract: An electro-mechanical drive apparatus uses a single variable speed motor, two one-way clutches, and a hydraulic accumulator to provide both hydraulic power for the linear motion axes and rotation of the plasticizing screw in an injection molding machine. When engaged, the first one-way clutch couples the drive motor to the pump stack, while the second one-way clutch couples the motor to the feed screw. During rotation of the drive motor in a forward direction; (a) the first one-way clutch engages, rotating the shaft of the hydraulic pump stack to power the machines hydraulic systems and charge the accumulator; and (b) the second one-way clutch slips. When the drive motor is rotated in a reverse direction, (a) the second one-way clutch engages, rotating the feed screw, and (b) the first one-way clutch slips. Preferably, the drive apparatus is associated with a double shaft motor mounted adjacent separate drive couplings for the feed screw and hydraulic pump stack.

Abstract: An accumulator head is convertible to alternate capacity ranges by providing a construction that has a segmented barrel with a matching ram in the purging system. More specifically, the accumulator barrel is divided into upper and lower segments so that the accumulator chamber is bounded by the lower barrel segment. The inner diameter of the lower barrel segment matches the outer diameter of the ram, and the length of the lower barrel segment corresponds roughly to the range of movement of the ram. With this accumulator construction, it is possible to change the working volume of the internal accumulator chamber by simply changing two parts, i.e., the lower barrel segment (inner diameter) and the ram (outer diameter). In addition, the two piece accumulator barrel design facilitates a more economical construction since the lower segment (where most of the wear occurs) can be made of a wear resistant grade of steel, while the upper segment can be manufactured from a lower cost, more easily machined material.

Abstract: A two-platen injection molding machine without tie bars has a platen fixed relative to the machine frame and a platen that moves relative to it, a traverse mechanism that operates the movable platen, a device for generating clamping force and a device to compensate for the deformation forces occurring during generation of the clamping force. The traverse mechanism and the device for generating clamping force are decoupled. Preferably, the device for generating clamping force has at least one connecting rod that passes through both the fixed and movable platens beneath the mold space. The connecting rod is detachably fastened to one of the platens and can be locked to the other platen by means of a clamping device that produces the clamping force. The device to compensate for the deformation forces includes at least one rigid spacer detachably fastened at one end to one platen, while the other end of the spacer is forced against the other platen.

Abstract: The invention is directed to a two-stage, all-electric injection unit. More specifically, an injection unit in which the feed screw is preferably used only for plastication and the injection of the plasticized material is accomplished by a separate accumulator having an electrically driven linear actuator, such as a ball screw mechanism. The accumulator is configured so that the ratio of the piston stroke to the piston diameter is preferably in the range of ten to fifteen. In the preferred embodiment there are separate motors for rotation of the screw and operation of the accumulator. An alternate embodiment is disclosed wherein the system is driven with a single motor and one-way clutches.

Abstract: A method for mold heater startup and sequencing detects the heater zones associated with greater mass and allows them to heat up before zones of lesser mass, thereby reducing wear of the associated mechanical components and minimizing degradation of plastic material. The zones of smaller mass are kept at minimal temperatures until the zones with greater mass reach a set point. The system is capable of detecting multiple levels of thermal load and provides appropriate sequential startup of the identified thermal loads. The operator may also manually program the system to override certain automated sequences in order to ensure an optimal startup sequence. The sequencing of power application to large heaters also minimizes the peak current draw of the system.

Abstract: A mold for molding or injection-molding polymer compounds, having at least one mold ancillary unit, in particular an ejector device (10), preferably an ejector pin, and/or a core pin device is distinguished by the fact that the mold ancillary device (10) has, at least over a region, a marker unit (18) in the region facing the polymer compound during the molding or injection-molding.

Abstract: An apparatus for heating and blending thermoplastic material prior to delivering the material into the barrel of an extruder. The apparatus, has an elongated housing which contains two intermeshing feed screws that are driven to rotate in the same direction. Controlled heating is provided by electric band heaters which encircle the exterior of the housing, and electric cartridge heating elements fitted into aluminum cores that are received by an axial bore in each of the feed screws.