Abstract:
An injection molding machine with an injection system and a clamping system. The injection system may include a removable injection module defining a portion of the material flow path. The injection module may include all of parts that come in contact with the material between the material source and the mold. The injection module may include a valve arrangement movable between a fill position to load the injection module with material and an inject position to eject material from the injection module into the mold. The actuators for the injection module may be supported on the machine rather than the injection module. The clamping system may include a platen linear actuator to open and close the mold, and a hydraulic clamping system to apply clamping force to the closed mold. The hydraulic clamping system may include a free-float valve manifold assembly that selectively places the hydraulic cylinders in free-float mode.
Abstract:
The clamping device has tie bars which are connected to a fixed platen and have engaged parts at a movable platen side, clamping cylinders which are provided on movable platens, half nut devices which are connected to pistons of the clamping cylinders and can mesh with the engaged parts, and stopper devices which restrict the movement of the half nut devices. Each stopper device has at least a driving unit and a stopper part which is driven in a mold opening and closing direction relative to the movable platen by driving of the driving unit and can engage with the half nut device from the fixed platen side. No winding transmission mechanism is interposed between the driving unit and the stopper part.
Abstract:
Die opening-closing means includes a servo motor and a movement conversion mechanism and is disposed between a support plate and a base stand. A movable plate is mounted on the support plate that is disposed on the base stand via a linear movement guide. In a forging cycle, die opening and closing is performed by activation of the die opening-closing means and tie bar fixing means at a rear surface side of the movable plate, and clamping force is obtained using a die clamping cylinder provided in the movable plate. When it is necessary to change over exclusive dies and change over is performed by: extending tie bar removal cylinders provided in a frame behind the movable plate so as to remove tie bars from a fixed plate; and moving a movable rail of internal rails to an open position and moving the change over carriage in along the internal rails from the outside.
Abstract:
A hybrid injection unit for an injection molding machine includes a plasticizing screw having a shaft and constructed for rotation and axial displacement. Operatively connected to the shaft is a first electric motor for rotating the plasticizing screw, and a second electric motor for axial displacement of the plasticizing screw. A cost-efficient construction of the second electric motor and reduced stress of the linkage between this electric motor and the shaft is realized by providing at least one piston and cylinder unit in fluid communication with a pressure source for support of the second electric motor in injection direction, and a traverse acted upon by one end of the piston and cylinder unit and rotatably supporting the shaft of the plasticizing shaft. The traverse acts upon the shaft between a force introduction point of the second electric motor into the shaft, on one hand, and the plasticizing screw, on the other hand.
Abstract:
An energy efficient drive system is provided for use on typical injection molding machines whereby a single electric motor drives both the extruder screw and a hydraulic motor that continuously charges a hydraulic accumulator during the extrusion process. During the injection cycle, the charge in the accumulator is directed to stroke the extruder screw and inject melt into the mold cavities. Another embodiment utilizes a similar arrangement on the clamp mechanism of the injection molding machine whereby the charge in the accumulator is directed to hold the mold closed during the injection cycle.
Abstract:
A drive device has a drive element movable axially by means of an electric motor and a hydraulic unit. In the drive device it is important to execute a rapid adjusting movement and then to exert high forces. This causes high reaction forces on the lifting spindle. High reaction forces are avoided if a force intensifier with two pistons movable in relation to one another and differing from one another in the size of their active surfaces along with an intermediate part which, together with the pistons, encloses a pressure space filled with a pressure fluid is used, if the smaller active surface is connected mechanically to the drive element, for the adjusting movement, the hydraulic unit can be moved as a whole, and if, for exerting a high force by means of the larger active surface, the intermediate part can be blocked against displacement in relation to a fixed stand.
Abstract:
The invention relates to a drive device, which is used in particular for the closing unit, the injection unit or the ejectors of a plastics injection molding machine and which has a drive element which can be axially moved by an electric motor and a hydraulic unit which, by moving the drive element, can be moved in the same direction as the latter. Drive devices for the stated applications depend on firstly performing a rapid positioning movement and then exerting great forces. In the case of a known drive device with the stated features, the hydraulic unit is a hydraulic cylinder, which is displaced during the positioning movement by the electric motor via a lifting spindle and to which pressure medium is supplied via a valve for the exertion of a great force. In the case of this known drive device, apart from the electrical installation, a complete hydraulic system is also necessary. Furthermore, great forces of reaction act on the lifting spindle. This is avoided if, according to the invention, the hydraulic unit is a force multiplier with two pistons, which can be moved in relation to one another and differ in the size of their effective surface areas, and an intermediate part, which together with the pistons encloses a pressure chamber filled with a pressure fluid, if the small piston, having the smaller effective surface area, is mechanically connected to the drive element, if the hydraulic unit as a whole can be moved for the positioning movement and if the intermediate part can be blocked against displacement in relation to a fixed frame for the exertion of a great force by the large piston, having the greater effective surface area.
Abstract:
The invention relates to a linear drive device for opening and closing molding tools and for applying a clamping force thereon, especially mold halves of a plastics molding machine. The device is comprised of a screw drive acting upon the molding tool, a first screw nut for opening and closing the molding tools and a piston/cylinder unit for applying a clamping force. In order to provide a linear drive device for opening and closing molding tools, especially mold halves of a plastics molding machine, which enables fast opening and closing of the molding tools and energy-optimized application of the clamping force to the molding tools, the piston/cylinder unit (113) acts upon the molding tool by means of a second screw nut (108).
Abstract:
The invention relates to a screw mechanism comprised of a screw shaft (1), a screw nut (2) and rolling bodies. When the screw mechanism is subjected to a high static load, the forces are transmitted from the screw shaft (1) to the screw nut (2) by means of the rolling bodies. As the contact surfaces between the rolling bodies, the screw nut (2) and the screw shaft (1) are very small, only relatively weak forces can be transmitted. In order to adapt the screw mechanism to high static loads, using simple construction measures, the surface of the screw shaft (1) between the grooves (4) of the rolling bodies is provided with locking structures which can be form-fittingly connected with complementary locking structures of locking elements (7, 8) which are moveable essentially transversally to the axis of the screw shaft (1).
Abstract:
A mold clamping apparatus for an injection molding machine comprises a stationary platen fixedly holding the stationary mold, a movable platen fixedly holding the movable mold and disposed opposite to the stationary platen, tie bars for guiding the movable platen for movement toward and away from the stationary platen, a movable platen driving mechanism for moving the movable platen along the tie bars to close and open the mold, a movable platen fixing mechanism for fixing the movable platen to the tie bars at a set position immediately before a position where the movable mold is joined to the stationary mold, and a clamping force applying mechanism that includes a sealed hydraulic cylinder actuator capable of converting energy of a hydraulic fluid into an intensified mold clamping force and of applying the intensified mold clamping force to the stationary platen. In one embodiment, the apparatus includes an electrically driven toggle mechanism which brings the movable and stationary molds together, at which point the hydraulic clamping force applying means applies significant clamping force to clamp the mold shut.