Abstract: A casting unit for a die casting machine has a casting container with a casting chamber, a casting piston, which is arranged in an axially movable manner in the casting chamber, a melt bath connection opening, a melt inlet channel from the melt bath connection opening to the casting chamber, a melt outlet channel, which leads out of the casting chamber separately from the melt inlet channel, and a shut-off control valve for the melt inlet channel. The shut-off control valve has a valve main body arranged on the casting container, a valve seat and a valve closing body.

Abstract: A blow molding apparatus that supplies a pressurized liquid into a bottomed tubular preform fitted to a mold used for blow molding and molds the preform into a shape conforming to a cavity of the mold, the blow molding apparatus including: a blow nozzle fitted to a mouth tubular portion of the preform; a plunger pump configured to supply the pressurized liquid into the preform through the blow nozzle; and a control device configured to change an actuation rate and an actuation force of the plunger pump during the supply of the pressurized liquid into the preform to regulate a peak pressure of the liquid supplied into the preform to be from 3.5 MPa to 5.0 MPa.

Abstract: An injection pump for the hot-chamber die casting of corrosive light alloys includes a body provided with an internal coaxial liner where an injector piston sealingly slides. The liner being made of a material resistant to the molten alloy and has a coefficient of thermal expansion different from the material of the body. Static sealing elements, made of a graphite-based non-metallic material that yields under compression, are arranged between the internal surface of the body and the external surface of the liner. The pump also has axial compression means arranged between a ring nut screwed into the body and the liner and the static sealing elements.

Abstract: The invention relates to a diecasting die (7) and a diecasting method for sprueless diecasting, in particular in a diecasting hot-runner system (1), wherein the diecasting die (7) is provided in a feeding region (8) for forming a plug of solidified molten material (22) that interrupts a flow of the molten material and can be completely remelted. The problem addressed by the present invention is therefore that of providing a diecasting die and a diecasting method according to the preamble of the invention that are suitable for different molten materials, in which a heating acts directly on the molten material with high power and largely without delay, a cooling is not required and the injection-molding method can be carried out at a high operating machine speed and under feeding conditions that can be monitored and reproduced well. The problem is solved by the feeding region (8) comprising direct resistance heating that produces a melting heat and is in direct thermal contact with the molten material (22).

Abstract: Various embodiments provide apparatus and methods for injection molding. In one embodiment, a constraining plunger may be configured in-line with an injection plunger to transfer a molten material from a melt zone and into a mold. The constraining and injection plungers are configured to constrain the molten material there-between while moving. The constrained molten material can be controlled to have an optimum surface area to volume ratio to provide minimized heat loss during the injection molding process. The system can be configured in a longitudinal direction (e.g., horizontally) for movement between the melt zone and mold along a longitudinal axis. A molded bulk amorphous object can be ejected from the mold.

Abstract: A die casting system includes a die, a shot tube, a shot tube plunger and a melting unit. The die includes a plurality of die components that define a die cavity. The shot tube is in fluid communication with the die cavity. A shot tube plunger is moveable within the shot tube to communicate a charge of material into the die cavity. The melting unit is positioned relative to the die and includes a bottom portion having an opening for selectively releasing a charge of material through the bottom portion.

Abstract: The present invention is a casting machine for casting parts in a mold out of a metal using a metal feed stock. The machine includes a processing cylinder formed in a thermally conductive block, said processing cylinder having a processing chamber and opposite first and second ends, the first end of the processing cylinder being configured to receive the metal feed stock. The machine further includes an injector cylinder formed in the thermally conductive block adjacent the processing cylinder, the injector cylinder having a shooting pot coupled to the second end of the processing cylinder by a passage configured to permit feed stock to pass from the processing cylinder into the shooting pot, a nozzle coupled to the injector cylinder configured to couple to the mold. The device includes a processing drive for driving the feed stock from the first end of the processing cylinder through the passage into the shooting pot and a heater thermally coupled to the processing cylinder.

Abstract: A method and apparatus for the casting of metal components is disclosed. The apparatus includes a gooseneck for drawing molten metal from a crucible of hot metal and for forcing the drawn molten metal through the system, a hot runner assembly having a hot runner tip positioned adjacent the mold cavity, and a machine nozzle inserted between the gooseneck and the hot runner assembly. The gooseneck is fitted with a one-way check valve to allow for molten metal to be drawn into the plunger but to stop its passage out of the gooseneck when the metal is forced through the system into the die. A thermal valve is formed within the hot runner tip to provide a metal blockage from the molten metal which prevents the back-flow of molten metal back into the hot runner assembly. Both temperature and flow rate are carefully monitored and controlled.

Abstract: A method and apparatus for the casting of metal components is disclosed. The apparatus includes a plunger for drawing molten metal from a crucible of hot metal and for forcing the drawn molten metal through the system, a hot runner assembly having a nozzle tip positioned adjacent the mold cavity, and a machine nozzle disposed between the plunger and the hot runner assembly. An adaptive and universal hot runner manifold having removable hot runner injectors fitted thereto is provided for use with a variety of castings.

Abstract: A metering device for a hot chamber die-casting machine includes a casting container attachable to a crucible of the hot chamber die-casting machine, a riser channel in a riser channel area, and a casting piston unit for metered conveying of melt out of the crucible via the riser channel. A heating device is provided with a flameless heating unit for active heating of at least a part of the riser channel area. The heating unit is placed inside a piston rod leadthrough bore, electrically insulated from the riser channel in a riser bore containing the riser channel, or in a heater receiving space specially provided in the casting container.

Abstract: The present invention is a casting machine for casting parts in a mold out of a metal using a metal feed stock. The machine includes a processing cylinder formed in a thermally conductive block, said processing cylinder having a processing chamber and opposite first and second ends, the first end of the processing cylinder being configured to receive the metal feed stock. The machine further includes an injector cylinder formed in the thermally conductive block adjacent the processing cylinder, the injector cylinder having a shooting pot coupled to the second end of the processing cylinder by a passage configured to permit feed stock to pass from the processing cylinder into the shooting pot, a nozzle coupled to the injector cylinder configured to couple to the mold. The device includes a processing drive for driving the feed stock from the first end of the processing cylinder through the passage into the shooting pot and a heater thermally coupled to the processing cylinder.

Abstract: An injection molding apparatus includes a melt furnace and a metal supply system located in the melt furnace. The metal supply system includes a pump. The injection molding apparatus also includes a first metal inlet from the melt furnace to the metal supply system and a vertical injection mechanism adapted to inject liquid metal into a die system. The injection molding apparatus also includes a second metal inlet from the metal supply system to the vertical injection mechanism.

Abstract: A diecast machine comprises: a sleeve extending in the vertical direction; a plunger moving upward in the vertical direction inside the sleeve; a mold disposed above an upper side of the sleeve; a case member constituted of a nonconductive member, which covers at least a lower end of the sleeve and forms a closed space including the lower end of the sleeve; a communicating pipe connecting the inside of the closed space to the outside of the closed space; and high-frequency induction coil configured to heat metal material disposed on the plunger from the outside of the case member and melt the metal material.

Abstract: In a motor drive injection unit and a motor drive injection method, which can obtain an injection speed suitable for a molding material having fast solidifying speed as well as can securely carry out pressure keeping for a predetermined period of time while making a position of an injection piston unmovable after injection and filling are completed, a molding material in a cylinder is injected into a metal mold by converting a rotational motion of an electric servo motor into a reciprocating motion of an injection piston in the cylinder through a plunger with a ball screw, a surge pressure control means is provided for placing the injection piston in the cylinder in an unmovable state when at least a predetermined amount of a load is applied to the injection piston by the molding material in the cylinder, the surge pressure control means includes a combination of rotation control means of the electric servo motor and an upward movement suppression mechanism of the injection piston, and further, an injection s

Abstract: In a metal molding machine provided having a tilt to a clamping device with an injection unit which is constituted by a liquid metallic material reservoir in which a cylinder having a nozzle portion at the tip portion equipped with a heating device at the outer periphery and an injection plunger having advance or retreat freely in the inside, and the injection cylinder at the rear portion, the metallic material feeding to the above liquid metallic material reservoir is performed in liquid by melt to the temperature of above the liquidus temperature in a melting cylinder standing the liquid metallic material reservoir to liquid metallic material surface from a feeding pipe having a smaller diameter than the inner diameter of the cylinder. The melting and feeding of metallic material is performed at an atmosphere of an inert gas such as argon.

Abstract: An injection molding apparatus includes a melt furnace and a metal supply system located in the melt furnace. The metal supply system includes a pump. The injection molding apparatus also includes a first metal inlet from the melt furnace to the metal supply system and a vertical injection mechanism adapted to inject liquid metal into a die system. The injection molding apparatus also includes a second metal inlet from the metal supply system to the vertical injection mechanism.

Abstract: An injection unit for a hot-chamber die-casting machine has an injection portion with a gooseneck and a nozzle adaptor. The injector portion has a base portion at an end of the gooseneck adapted to receive a molten medium supply. A nozzle at an end of the nozzle adaptor is adapted to inject the molten medium supply in a die cavity. A channel between the base portion and nozzle is adapted to convey the molten medium supply therethrough. A piston chamber in the base portion is actuatable to draw the molten medium supply therein and to direct the molten medium supply in the channel for injection into the die cavity. An actuation portion is connected to the gooseneck to actuate the piston chamber. Heating cartridges are received in the injection portion adjacent to the channel to control temperature of the molten medium supply in the channel.

Abstract: An injection device for a light metal injection molding machine includes a melting device for melting light metal material into molten metal, plunger injection device for carrying out injection of molten metal using a plunger after the molten metal is metered into an injection cylinder from the melting device, connecting member including a connecting passage for connecting the melting device and the plunger injection device, and backflow prevention device for preventing backflow of molten metal by opening and closing the connecting passage.

Abstract: The invention is relating to a system for casting metal, the system comprising a holding furnace (3) containing a base metal melt (2), at least one casting crucible (1) mounted inside the holding furnace (3) and situated at least partly in the base metal melt (2), the said casting crucible (1) divided to at least first volume (4) and second volume (5) with a separating wall (6), which separating wall (6) is forming a gap (10) with the casting crucible wall (11) said casting crucible (1) having at least one opening (12) in the wall (11) from the first volume (4) to the base metal melt (2) in holding furnace (3) and having means to import alloying material (7) to the first volume (4) and having at least one casting die (8) in the second volume (5) inserted into the alloyed metal melt (9). The invention also relates to a method of casting metal.

Abstract: A multiple-slide die-casting machine for casting pieces has a frame. A table is operatively mounted to the frame. A slide guiding mechanism is secured to the table and has slides. Each slide has a die section. The slides are actuatable in a close/open action such that the die sections mate to form a die cavity. An injection unit is mounted to the frame and is adapted to be connected to a molten medium supply. The injection unit has a nozzle and is adapted to inject molten medium from the supply into the die cavity through the nozzle for casting a piece. A relative displacement configuration is provided between the table and the injection unit such that the die sections on the table are disengageable from with the nozzle for injection of a cast product from the die cavity.

Abstract: This assembly is for use with hot chamber die casting. More specifically, the assembly is a fast fill bottom fill gooseneck. The intake port has been moved to the bottom of the gooseneck. The bottom intake port has been fitted with an interior plug. When the plunger moves upwardly, it creates a vacuum the pulls the interior plug upwardly. This vacuum also opens the bottom intake port pulling molten metal into the chamber from the reservoir. When the plunger moves downwardly, the interior plug moves downwardly and seals the bottom intake port. As the plunger continues to travel downward, it pressurizes the molten metal and forces the molten metal contained in the cylinder through the channel in the gooseneck, through the nozzle seat and the nozzle into the die cavity of the die thereby filling the cavity and forming the cast part.

Abstract: A pouring apparatus for castings uses separate systems for supplying billets and delivering the semi-molten material, making it possible to readily modify the discharge flows and pressure. A pouring apparatus for castings that comprises solid material supply means for supplying solid material to a melting basin; heating means for heating the melting basin to semi-melt solid material supplied to the melting basin; a conveyance chamber provided adjacent to the melting basin; and delivery means for discharging, from a discharge nozzle, semi-molten material conveyed from the melting basin to the conveyance chamber.

Abstract: A device for producing nonferrous metal diecast parts is described in which a hot-duct gate system is disposed in front of mold cavities, by means of which hot-duct gate system, it is possible to guide the hot molten metal closely in front of the mold cavities and to maintain it in the liquid condition until the next shot. As a result, solidified overflows or runner ducts and pressing residues are avoided. The new device can therefore operate in a very economical and precise manner.

Abstract: A multiple-slide die-casting machine for casting of magnesium pieces, comprising a frame. A table is operatively mounted to the frame. A slide guiding mechanism is secured to the table and has slides. Each slide has a die section at an operating end thereof. The slides are actuatable in a close/open action such that the die sections mate at a parting line therebetween to form a die cavity. An injection unit is mounted to the frame and is adapted to be connected to a molten magnesium supply means. The injection unit has a nozzle and is adapted to inject molten magnesium from the supply means into the die cavity through the nozzle for casting a piece.

Abstract: A method of operating a hot-chamber diecasting machine is provided in which, after the filling of the mold, a compressional vibration is generated which prevents the molten metal from rapidly solidifying at least in the narrowest cross-section of the feed orifice between the ascending bore and the mouthpiece and the mold. In this manner, it becomes possible to increase the afterpressure upon the molten metal in the mold in comparison to conventional hot-chamber diecasting processes in order to achieve cast parts of a higher quality.

Abstract: A multiple-slide die-casting machine for casting of magnesium pieces, comprising a frame. A table is operatively mounted to the frame. A slide guiding mechanism is secured to the table and has slides. Each slide has a die section at an operating end thereof. The slides are actuatable in a close/open action such that the die sections mate at a parting line therebetween to form a die cavity. An injection unit is mounted to the frame and is adapted to be connected to a molten magnesium supply means. The injection unit has a nozzle and is adapted to inject molten magnesium from the supply means into the die cavity through the nozzle for casting a piece.

Abstract: A method is described of operating a hot-chamber pressure diecasting machine and a pressure diecasting machine suitable for the implementation of this method, by which a prefilling of the casting system can be carried out before the actual mold filling operation. During this prefilling operation, the air present in the casting system after each shot when the casting plunger is withdrawn, is pressed out during this prefilling operation through the mold which is still open during this time period. This amount of air therefore no longer has to escape during the subsequent mold filling operation. The mold filling operation and the pressing-in operation can therefore be implemented more effectively and within a shorter period of time.

Abstract: A multiple-slide die-casting machine (20) is equipped with improved mechanical structure and unique injection control system to improve the quality of molded products, to achieve flash free castings of improved surface finish. The clamping assemblies (52A, 52B, 52C, 52D) are mounted on one side of a base plate (22) of the machine for applying clamping force to the mold sections in a preloaded state. A reinforcement ring (56) interconnects the clamping assemblies to inhibit deflection of the base plate and the brackets (72) which support the clamping assemblies so that an accurate parting line between the contacting surfaces of mold sections is insured.

Abstract: A pressing-in unit for a hot-chamber pressure diecasting machine permits an electro-mechanical drive for the casting plunger. In order to absorb the moments of inertia of the drive which occur during the switch-over of the casting plunger drive from the mold filling phase to the after-pressure phase, a spring element in the form of a plastic component or a liquid spring is inserted between the casting plunger and the pusher rod moved by the electric drive, which spring element is compressed by the additional path which the pusher rod still covers after the braking of the motor. The extent of the compression is selected such that the resulting axial force which is exercised by the plastic component or by the liquid spring is sufficient for causing the desired after-pressure in the molten metal.

Abstract: A method is described of operating a hot-chamber pressure diecasting machine and a pressure diecasting machine suitable for the implementation of this method, by which a prefilling of the casting system can be carried out before the actual mold filling operation. During this prefilling operation, the air present in the casting system after each shot when the casting plunger is withdrawn, is pressed out during this prefilling operation through the mold which is still open during this time period. This amount of air therefore no longer has to escape during the subsequent mold filling operation. The mold filling operation and the pressing-in operation can therefore be implemented more effectively and within a shorter period of time.

Abstract: A reinforced casting assembly formed of ferrous metal for use with hot chamber die casting including a gooseneck, nozzle seat and nozzle. Reinforcing members are used to reinforce the casting. The preferred embodiment is reinforcing the gooseneck as this is where most failures created by the high internal pressure of hot melt die casting occur. The reinforcing members generally are made of steel wire such as a solid or braided wire.

Abstract: Hot-chamber diecasting machines for processing magnesium melts include a casting vessel, an inductive heating system, and an additional ring inductor in an area of the neck of the casting vessel in order to achieve a heating also in this area. The ring inductor is formed of a one-piece tube made of an elastic material which is open at one point and can be bent open by the extent of the diameter of the neck of the casting vessel and can be pushed laterally onto the casting vessel, and through which air can also flow for the cooling.

Abstract: The method includes the steps of a tape arranging step for arranging a support tape of a slide fastener on a mold having a capacity having a plurality of unit fastening element molding material grooves for molding a plurality of unit fastening elements, a molding material heating and discharge step for separating a molding material of more than two colors from a source material supply unit by the colors by a molding material injection means and then heating and discharging the same, a moving step for grouping external molding material flow paths from the molding material supply unit to an injection port of the mold into more than two groups and then moving different colors molding material by the colors, and an injection step for injecting the molding material into the unit fastening element molding material groove through a plurality of inject-on ports formed in the mold.

Abstract: The injector includes a cylinder defining a piston cavity housing a reciprocating piston for pumping molten metal from a holder furnace and injecting the molten metal into the mold cavity of a casting mold. The piston defines a molten metal intake for receiving molten metal into the piston cavity. A check valve is positioned in the molten metal intake defmed by the piston. The check valve is preferably a ball check valve. The cylinder further defines a fill conduit in fluid communication with the piston cavity. The fill conduit extends through a top wall of the cylinder and extends along an axis substantially parallel to the piston.

Abstract: A hot chamber die-casting machine has drive assemblies in the form of electrical servomotors instead of hydraulic cylinders for driving and pressing a feed bush to the nozzle. The feed rate of the servomotors is adjustable. In order to avoid the influence of heat from the smelter and the furnace, the rotational axes of the servomotors located above the smelter and the furnace are connected through an angle drive to the spindle drive and aligned approximately vertically. This makes it possible to achieve a time-optimized and precise feed regulation that is independent of temperatures which develop.

Abstract: A device for producing nonferrous metal diecast parts is described in which a hot-duct gate system is disposed in front of mold cavities, by means of which hot-duct gate system, it is possible to guide the hot molten metal to shortly in front of the mold cavities and to maintain it in the liquid condition until the next shot. As a result, solidified overflows or runner ducts or pressing residues are avoided. The new device can therefore operate in a very economical and precise manner.

Abstract: A method of operating a hot-chamber diecasting machine is provided in which, after the filling of the mold, a compressional vibration is generated which prevents the molten metal from rapidly solidifying at least in the narrowest cross-section of the feed orifice between the ascending bore and the mouthpiece and the mold. In this manner, it becomes possible to increase the afterpressure upon the molten metal in the mold in comparison to conventional hot-chamber diecasting processes in order to achieve cast parts of a higher quality.

Abstract: A vertical adjustment device for a mold closing unit of a hot chamber die-casting machine is provided with a shear mechanism. An electrical servomotor is provided as a drive assembly for spreading the shear mechanism apart, with the axis of the servomotor being parallel to the guide surface for the shear mechanism and driving, through an angle transmission, a spindle oriented at less than 90° with respect to the drive axis of the servomotor. One end of each of the two lever pairs of the shear mechanism is connected pivotably with the closing unit or with the machine frame. The other ends are supported on the guide surface and the machine frame and on a guide surface of the closing unit.

Abstract: A hot chamber method of die casting material in a semisolid state. The semisolid material has a high viscosity, which can be controlled by controlling the fraction of solid phase and the morphology of the solid phase. By controlling the viscosity of the melt, turbulence and consequent gas entrapment can be minimized or eliminated. Further, shrinkage is substantially reduced, thereby reducing porosity and hot tearing to form stronger, more reliable castings.

Abstract: A sealing and guiding device for the injection piston (3) of a hot chamber pump for corrosive alloys made up of a body (1) in which a chamber (6) and an injection cavity (2) therebelow are formed, wherein the piston (3) slides with a vertical reciprocating motion (V), includes a bush (8), having an outer diameter smaller than said chamber (6), interposed between centering members housed in the chamber (6) and made coaxial with the chamber (6) and with the piston (3) by a pair of opposite surfaces of revolution (12, 13) formed on said centering members, the upper surface (13) and the relevant centering member performing a pressure-tight sealing. The outer lateral surface (15) of the bush (8) is in communication with the injection cavity (2) whereas the upper side of the bush (8) is in communication with the crucible and immersed therein at a depth (L), measured from the lowest level (23) reachable by the molten alloy, which is greater than the maximum travel (C) of the piston (3).

Abstract: A hot chamber die casting machine for casting aluminum and its alloys includes separated ceramic parts, namely a ceramic injection cylinder constituting a pump body, a ceramic outer sleeve, a ceramic injection pipe, and a metallic or thermet flange avoiding a large one piece ceramic body and stress concentrations at critical points. The outer sleeve holds the injection cylinder together with the injection pipe in the molten metal. The flange is fixed to a structure which is outside of and independent from a molten metal container and a heating furnace, thus temperature fluctuations do not affect this injection apparatus. The flange can also be fixed to the structure to which an injection hydraulic cylinder is secured in such a manner that the centers of the hydraulic cylinder, the plunger and the injection cylinder are aligned to perform a stable injection operation. A seal ring is disclosed between no-parallel conical cone shaped-fitting ends between the injection pipe and the injection cylinder.

Abstract: An injection molding machine having a simple structure and adapted to quickly produce molded products without significant flaws on the surface is provided. It comprises a plunger being adapted to introduce the molten metal into the cylinder section, a nozzle for injecting the molten metal fed from the plunger into a metal mold and a piston arranged within a cylinder section of the plunger to slidingly reciprocate. It includes a piston drive unit for driving the piston to slidingly reciprocate, a stopper member for controlling the retracted position of the piston drive unit and a position selecting unit for defining a projected position and a retracted position for the stopper member.

Abstract: In a hot chamber die-casting machine, inductively-operating heating devices are associated with the mouthpiece area of the casting container and the nozzle. All of these heating devices are operated with medium frequency. The inductors are cooled with air. The machine is useful for hot chamber die-casting machines that process magnesium.

Abstract: In order to improve the compression operation and to produce better products with thin-walled castings, the invention calls for the compression operation to be divided into three phases and controlled by high-dynamic continuous-operation valves which have very short switching times and are actuated by a control device. Fitted in the hot-chamber die-casting machine for this purpose is a metal sensor which is disposed in a die relief leading from the rising bore in the casting container into the mould.

Abstract: Apparatus for casting metals, especially alloys with low melting points, has a melt container which is connected to a mold via a casting line. A standpipe branches off from the casting line in the melt container. The melt is covered by an inert fluid blanket and the level of melt in the melt container is monitored and maintained such that at least a portion of the standpipe is surrounded by the melt. An overflow valve selectively opens or closes an overflow hole in the standpipe, the overflow hole being immersed in the inert fluid, to adjust the level of melt in the casting line.

Abstract: The die has first and second die halves, each die half having a plurality of cavities that, when the die halves are in a closed position, align with the cavities in the other die half, thus defining a plurality of voids that define the objects to be formed. Each cavity is aspherical in that the slope of the cavity is never perpendicular to the front surface of the die half, thus facilitating the removal of the objects from the die. A spacing between the front surfaces of the die halves during the injection step of the cycle helps to increase the number of parts that properly release from the die.

Abstract: A pump for the hot chamber die casting of corrosive light alloys including a body (2) wherein a cavity (3) is formed in which a piston (4) vertically reciprocates and on whose side wall (5) an opening (11) for the introduction of the molten alloy (1) and the mouth of a sprue (9) for the connection with the mold (10) are formed. The diameter of the piston (4) is smaller than that of the cavity (3) so that it may move without rubbing on the wall (5) as it is guided by a seal packing (6) detachably constrained to the mouth of the cavity (3), the opening (11) being closed during the compression of the alloy in the cavity (3) by a valve (12) controlled from outside through a lever (13).

Abstract: A die casting machine having a frame comprising two connecting rods, two side platens, a moving platen, connecting rod apertures in said moving platen, a moving platen drive and two dies, wherein one side platen is connected to the two connecting rods, the other side platen is connected to the opposite ends of the two connecting rods, the moving platen is guided by said two connecting rods for movement towards or away from respective side platens by said moving platen drive, one die mounted on one face of the moving platen and the other die mounted on the inside face of one side platen, all said platens being located in parallel planes at right angles to the centerline of the machine, the two connecting rods, the moving platen drive and the dies being in a common plane passing through the longitudinal centerline of the die casting machine.

Abstract: An injection apparatus for a hot-chamber die-cast machine including a cylindrical sleeve; a plunger body slidingly movably disposed in the sleeve and having a circumferential groove on an outer cylindrical surface and passages extending from a pressurizing face to the groove. Divided seal rings fit loosely in the groove of the plunger body in such a manner that the divided rings are urged radially outwardly by the pressure of the molten metal in the sleeve through the passages when the plunger body is moved. The divided rings satisfy the following conditions:t.sup.3 .ltoreq.4.5.times.10.sup.2 (mm).times.D.sup.2 .times.P/Ewhere t: thickness (mm) of the divided rings, E: Young's modulus (Pa) of the divided rings, D: inner diameter (mm) of the sleeve, and P: pressure (Pa) which should be exerted onto the molten metal when injected.

Abstract: A machine for producing metal die castings is disclosed and comprises a crucible that incorporates an injection pump assembly which is mounted in such a way as to clear the upper access of the crucible to facilitate cover sealing and removing. The crucible is located in a furnace and is reciprocable to move the injection barrel and nozzle to and from a mold. The injection barrel is immersed in the crucible beneath the level of the molten metal to enhance heat transfer between the barrel and injected metal. The separate plunger and shot assemblies are located in the pump body in a "V" configuration so that maintenance of these units can be carried out without exposing the top of the furnace to the atmosphere.