Abstract: An injection molding machine includes a machine base; a stationary platen fixed to the base for holding a stationary mold section; a moving platen slidably supported by the base for holding a moving mold section; a rotary apparatus slidably supported by the base axially intermediate the stationary and moving platens for supporting a plurality of center mold sections and moving the center mold sections among axial positions directed toward the stationary and moving mold sections and lateral positions directed toward the operator and non-operator side of the machine; and a part-handling apparatus mounted to the stationary platen. The part-handling apparatus includes an end-of-arm tooling disposed laterally outboard of the rotary apparatus. The end-of-arm tooling is movable laterally between an engaged position for interacting with molded articles in one of the center mold sections in the lateral positions, and a disengaged position spaced laterally outwardly from the engaged position.

Abstract: An injection apparatus includes (a) a barrel; (b) a nozzle at a front end of the barrel; (c) a screw in the barrel; and (d) a drive assembly including: (i) a housing having a front end coupled to the barrel; (ii) a spindle in the housing and fixed to the screw; (iii) a first motor in the housing and having a hollow first rotor through which the spindle passes. The first rotor is coupled to the spindle for driving rotation of the screw about the axis. The drive assembly further includes (iv) a second motor in the housing axially rearward of the first motor. The second motor has a hollow second rotor through which the spindle passes. The second rotor is coupled to the spindle for translating the screw along the axis in response to rotation of the second rotor relative to the spindle.

Abstract: An injection unit for an injection molding machine includes a cylindrical body rotatably supported in a housing interior for rotational coupling with a plasticizing screw. The cylindrical body is fixed to rotate with the plasticizing screw about an injection axis. A gear train in the housing includes a central gear mounted about, and fixed to rotate with, the cylindrical body, the central gear having an uppermost extent vertically above the injection axis and opposed first and second lateral extents on horizontally opposed sides of the injection axis. A rotary drive for powering rotation of the plasticizing screw includes a first motor having a first motor shaft rotatable about a first motor axis, the first motor axis parallel to the injection axis, the first motor axis at a first elevation below the uppermost extent of the central gear, and laterally outboard of the first lateral extent of the central gear.

Abstract: A platen apparatus for supporting a mold portion in an injection molding machine includes a platen body and a mold mounting face adjacent a front of the platen body for supporting a mold half. The mold mounting face includes a rotary central surface that is rotatable about an axis relative to the platen body and a fixed peripheral surface that is fixed relative to the platen body. The peripheral surface is disposed about a periphery of the central surface. The central surface and the peripheral surface are alignable in a common vertical plane.

Abstract: A two-platen clamp apparatus for an injection molding machine includes a first platen having a first mold mounting surface and a second platen having a second mold mounting surface. A first rail and a second rail extend parallel to each other and to a machine axis, the first and second rails disposed at a rail elevation vertically below the machine axis. The second platen is slidably coupled to the first and second rails and translatable between mold-closed and mold-open positions. At least one force-exertion member is coupled to the second platen for clamping the first and second platens together, each clamping force exerted along an axis parallel to and offset vertically below the machine axis. At least one force-reaction member is coupled to the first and second platens for resisting separation of upper portions of the first and second mold mounting surfaces during exertion of the clamping force, each of the at least one force reaction member disposed at an elevation below the machine axis.

Abstract: An injection molding machine includes a stationary platen and a moving platen mounted on a machine base, and a rotary apparatus for rotatably supporting a center mold section. The rotary apparatus includes a carriage body including a carriage upper portion supported by first and second carriage rails, and a carriage lower portion extending downward from the carriage upper portion laterally intermediate the first and second carriage rails. The rotary apparatus further includes a rotary table mounted atop the carriage body for rotatably supporting the center mold section. The rotary table is mounted to the carriage body by a rotary table bearing having a combination of bearing elements to bear axial, rotational, and moment loads. The machine further includes a plurality of tie bars extending between the moving platen and the stationary platen. The tie bars are free from engagement by the rotary apparatus.

Abstract: A shooting pot assembly for a two-stage injection unit includes: (a) a housing; (b) a plunger chamber in the housing; (c) an injection plunger in the plunger chamber; and (d) a conduit network including (i) a feed conduit, (ii) an outlet conduit, and (iii) a transfer conduit. The shooting pot assembly further includes (e) a purge valve assembly having a purge conduit open to the plunger chamber and in fluid communication with the transfer conduit via the plunger chamber when the plunger is in the advanced position. The purge valve assembly further includes a purge valve closure member movable between a closed position, in which the purge conduit is blocked, and an open position, in which the purge conduit is open for flushing stale melt from the transfer conduit through the purge conduit via supply of fresh melt into the transfer conduit from the feed conduit.

Abstract: A method of operating an injection molding machine includes translating a movable platen from a closed position to a part transfer position by overshooting the transfer position in an opening direction away from a stationary platen to an over-travel position, and then translating the moving platen back to the transfer position in a closing direction, opposite the opening direction. Movement of a take-out device towards an advanced position, in which the take-out device reaches between mold halves carried by the stationary and movable platens, occurs while the movable platen is moving between the over-travel and transfer positions, prior to coming to rest in the transfer position. When resting in the transfer position, the method includes transferring molded articles from a first mold section mounted to the movable platen to retained engagement on the take-out device reaching between the platens.

Abstract: A method for controlling an injection cycle of an injection molding machine incudes advancing an injection screw axially forward toward an injection nozzle from a shot-size position to an injection position to inject melt from a shot chamber into a hot runner of a mold and from the hot runner to fill cavities of the mold. Then the injection screw is retracted away from the nozzle, from the injection position to a decompression position axially rearward of the shot-size position, to relieve melt pressure in the hot runner. Then the screw is advanced toward the nozzle from the decompression position to an intermediate position axially intermediate the injection position and the shot-size position. The method then includes rotating the screw to re-fill the shot chamber with melt and urge the screw to retract from the intermediate position to the shot-size position.

Abstract: A platen apparatus for a mold center section of an injection molding machine includes a first mold mounting surface on a first front face of a first wall, the first mold mounting surface for supporting a first mold section, and a second mold mounting surface on a second front face of a second wall, the second wall spaced apart from the first wall in an axial direction and providing a generally hollow chamber therebetween. The second mold mounting surface is for supporting a second mold section and is directed away from the first mold mounting surface. The platen apparatus further includes a plurality of compression members extending between the first and second walls for maintaining a wall spacing between the first and second walls, and an ejector assembly mounted between the first and second walls for ejecting molded articles from the first and second mold sections.

Abstract: A clamp assembly for an injection molding machine includes a clamp piston slidable within a housing among a clamping position, a mold break position, and a meshing position disposed axially intermediate the clamping and the mold break positions. A clamp chamber urges the clamp piston towards the clamping position when pressurized, and a return device urges the clamp piston from the clamping position to the meshing position when pressure in the clamp chamber is relieved. At least one mold break actuator is coupled to a mold break engagement surface disposed within the housing. The mold break actuator is adjustable to accommodate retraction of mold break surface when the clamp piston moves to the clamping position, and to forcefully push the mold break surface forward against the clamp piston when moving the clamp piston to the mold break position.

Abstract: An injection unit for an injection molding machine includes a cylindrical body rotatably supported in a housing interior for rotational coupling with a plasticizing screw. The cylindrical body is fixed to rotate with the plasticizing screw about an injection axis. A gear train in the housing includes a central gear mounted about, and fixed to rotate with, the cylindrical body, the central gear having an uppermost extent vertically above the injection axis and opposed first and second lateral extents on horizontally opposed sides of the injection axis. A rotary drive for powering rotation of the plasticizing screw includes a first motor having a first motor shaft rotatable about a first motor axis, the first motor axis parallel to the injection axis, the first motor axis at a first elevation below the uppermost extent of the central gear, and laterally outboard of the first lateral extent of the central gear.

Abstract: A clamp assembly for an injection molding machine includes (a) a clamp cylinder housing and (b) a clamp piston affixed to an end portion of a tie bar and slidable within the housing among a clamping position, a mold break position, and a meshing position disposed axially intermediate the clamping and the mold break positions. The clamp assembly further includes (c) a clamp chamber for urging the clamp piston towards the clamping position when pressurized; (d) a return device for urging the clamp piston towards the meshing position when pressure in the clamp chamber is relieved; and (e) a mold break chamber for urging the clamp piston towards the mold break position when pressurized. The mold break chamber is bounded axially by opposed surfaces of the tie bar and the return device.

Abstract: A method of operating an injection molding machine includes translating a movable platen from a closed position to a part transfer position by overshooting the transfer position in an opening direction away from a stationary platen to an over-travel position, and then translating the moving platen back to the transfer position in a closing direction, opposite the opening direction. Movement of a take-out device towards an advanced position, in which the take-out device reaches between mold halves carried by the stationary and movable platens, occurs while the movable platen is moving between the over-travel and transfer positions, prior to coming to rest in the transfer position. When resting in the transfer position, the method includes transferring molded articles from a first mold section mounted to the movable platen to retained engagement on the take-out device reaching between the platens.

Abstract: An injection molding machine includes a stationary platen and a moving platen mounted on a machine base, and a rotary apparatus for rotatably supporting a center mold section. The rotary apparatus includes a carriage body including a carriage upper portion supported by first and second carriage rails, and a carriage lower portion extending downward from the carriage upper portion laterally intermediate the first and second carriage rails. The rotary apparatus further includes a rotary table mounted atop the carriage body for rotatably supporting the center mold section. The rotary table is mounted to the carriage body by a rotary table bearing having a combination of bearing elements to bear axial, rotational, and moment loads. The machine further includes a plurality of tie bars extending between the moving platen and the stationary platen. The tie bars are free from engagement by the rotary apparatus.

Abstract: An injection molding machine includes a machine base; a stationary platen fixed to the base for holding a stationary mold section; a moving platen slidably supported by the base for holding a moving mold section; a rotary apparatus slidably supported by the base axially intermediate the stationary and moving platens for supporting a plurality of center mold sections and moving the center mold sections among axial positions directed toward the stationary and moving mold sections and lateral positions directed toward the operator and non-operator side of the machine; and a part-handling apparatus mounted to the stationary platen. The part-handling apparatus includes an end-of-arm tooling disposed laterally outboard of the rotary apparatus. The end-of-arm tooling is movable laterally between an engaged position for interacting with molded articles in one of the center mold sections in the lateral positions, and a disengaged position spaced laterally outwardly from the engaged position.

Abstract: An injection molding machine includes a base, a stationary platen fixed to the base for holding a first mold section, and a moving platen for holding a second mold section. The moving platen is slidably supported on a platen slide surface fixed to the base and moveable along a machine axis between a mold closed position, in which the moving platen is drawn towards the stationary platen, and a maximum daylight position, in which the moveable platen is spaced axially apart from the stationary platen by a platen opening. The machine further includes a carriage support structure slidably supporting a stack mold carriage for holding a mold center section. The stack mold carriage is translatable parallel to the machine axis between a carriage advanced position and a carriage retracted position spaced axially apart from the carriage advanced position by a carriage stroke length.

Abstract: A clamp assembly for an injection molding machine includes (a) a clamp cylinder housing and (b) a clamp piston affixed to an end portion of a tie bar and slidable within the housing among a clamping position, a mold break position, and a meshing position disposed axially intermediate the clamping and the mold break positions. The clamp assembly further includes (c) a clamp chamber for urging the clamp piston towards the clamping position when pressurized; (d) a return device for urging the clamp piston towards the meshing position when pressure in the clamp chamber is relieved; and (e) a mold break chamber for urging the clamp piston towards the mold break position when pressurized. The mold break chamber is bounded axially by opposed surfaces of the tie bar and the return device.

Abstract: A platen apparatus for supporting a mold portion in an injection molding machine includes a platen body and a mold mounting face adjacent a front of the platen body for supporting a mold half. The mold mounting face includes a rotary central surface that is rotatable about an axis relative to the platen body and a fixed peripheral surface that is fixed relative to the platen body. The peripheral surface is disposed about a periphery of the central surface. The central surface and the peripheral surface are alignable in a common vertical plane.

Abstract: A lock assembly for releasably coupling a platen to a tie bar of an injection molding machine includes first and second lock nut segments translatable in a transverse between locked and unlocked positions for respectively engaging and disengaging the tie bar, and a carrier assembly for coupling the lock nut segments to the platen. The carrier assembly provides a slide surface for slidably supporting the lock nut segments during the translation of the lock nut segments between the locked and unlocked positions, and the carrier assembly resiliently supports the slide surface for axial movement of the slide surface with the lock nut segments between an unloaded position in which the lock nut segments are spaced away from the platen by a clearance gap, and a loaded position in which the lock nut segments bear against the platen.