Abstract: A method of metering a metal material in a liquid phase in molding injection provides accurate and reliable transfer of the metal material. A heating cylinder housing a rotatable and axially movable screw, is inclined with its head pointing downward, so that the metal material in the liquid phase state flows down into a front chamber due to self-weight. At the forward position after injection, the screw is forced to retract to a set position, whereby a predetermined quantity of a liquid phase material primarily stored on the periphery of the head portion of the screw is accumulated by suction due to a negative pressure in the front chamber of the heating cylinder. Further, a constant quantity of the liquid phase material can be metered each time in the front chamber by stopping and then rotating the screw at a retraction position.

Abstract: The purpose of this invention is to prevent sludge from flowing into a measuring chamber by partitioning the inside of a melt cylinder into a melt stirring part and a molten metal flow passage part, and to stabilize supply of the metallic material and measurement of the molten metal. A nozzle member 14 of which the inside of the rear part is formed into a measuring chamber 13 is attached to the tip of a melt cylinder 11. The end face of the opening periphery of the measuring chamber 13 of the nozzle member 14 faced to the inside of the melt cylinder is projectingly formed into a ring-shaped bearing 14b. A hollow stirring shaft 16 provided with stirring blades 15 on the outer periphery is supported by the bearing 14b and a bearing member 21 in the rear end of the melt cylinder so as to be freely rotatable with a suction port 25 bored in the side wall of the tip part.

Abstract: The invention has an object to permit to make the accumulation amount and the temperature of molten metal in the metal material molding machine constant, by performing material supply and melting taking the accumulation amount as reference during the molding operation. The supply apparatus 11 and the agitation means 29 of metal material at the moment of operation starting are controlled to be inactive until the temperature of the melting vessel attains a predetermined value and to start operating when the predetermined temperature is attained, allowing to supply and agitate the metal material. The supply and the agitation of metal material after the predetermined temperature is attained, are performed while gradually supplying and agitating the metal material until metal material of at least 6 times or more of the maximum injection volume is accumulated in melt state.

Abstract: It is an object of the present invention to prevent oxidation during the metal melting, by suspending both heating and supply of metal material under the monitoring by measuring the oxygen concentration in the inactive gas atmosphere. A oxidation prevent method of melting metal material by a melting vessel 1 comprising inside a rotatable agitation member 8, having a weighing chamber 4 communicating with a nozzle member 2, and an injection member 9 advanceably and retractably inserting an extremity injection plunger 12 passing through the agitation member 8 in the weighing chamber 4, and the melting vessel being installed on a slant with the nozzle member 2 downside. The space area over the melted metal surface 15a of the melting vessel 1 is made into inactive gas atmosphere. The oxygen concentration in this space area is measured and monitored.

Abstract: Upward variations of a molten metal level in a container for melting metallic material shall be carried out by detecting variations of a liquid level inside a detector connected to a gas-pipeline, wherein a rise in the pipeline pressure causes the liquid level to move down. Communication is established by means of a gas-pipeline 13 for inert gas between that portion of a container for melting metallic material which is above a molten metal surface 15a and that portion of a detector 16 comprising a transparent tubular container 18 which is above a liquid surface 17a. Variations of the liquid level 17a inside the detector 16 due to a rise in the pressure inside the above-mentioned gas-pipeline 13 are detected as upward variations of the level of the molten metal surface.

Abstract: The purpose of this invention is to prevent sludge from flowing into a measuring chamber by partitioning the inside of a melt cylinder into a melt stirring part and a molten metal flow passage part, and to stabilize supply of the metallic material and measurement of the molten metal. A nozzle member 14 of which the inside of the rear part is formed into a measuring chamber 13 is attached to the tip of a melt cylinder 11. The end face of the opening periphery of the measuring chamber 13 of the nozzle member 14 faced to the inside of the melt cylinder is projectingly formed into a ring-shaped bearing 14b. A hollow stirring shaft 16 provided with stirring blades 15 on the outer periphery is supported by the bearing 14b and a bearing member 21 in the rear end of the melt cylinder so as to be freely rotatable with a suction port 25 bored in the side wall of the tip part.

Abstract: An injection apparatus for melted metals is provided to be capable of transferring the metals, melting them by the external heat, metering and degassing by employing a reservoir to reserve metals in liquid phase for the injection screw. The injection apparatus comprises a heating cylinder having a fore end portion which communicates with a nozzle member and of which internal diameter is made smaller to serve as a metering chamber, and an injection screw installed within the heating cylinder to be movable and rotational. A tip end of the injection screw is formed in a plunger having a diameter that can insert into the metering chamber with keeping a clearance for sliding. A reservoir, for reserving melted metals in liquid phase, consisting of an axis is provided between the plunger and a feeding portion containing screw flight around the axis.

Abstract: The invention has an object to permit to mold metal molds having a thixothropic structure by melting, agitating and weighing, injection molten metal in a melting vessel by combining separately functioning agitation means and injection means. The invention consists in supply granular metal material in a fusion vessel 11 having a weighing chamber 17 by a cylinder of required length communicating with a nozzle port at the extremity section, including rotatively an agitation means 21 inside, and wherein an injection means 22 whose extremity section is formed into an injection plunger 30 is inserted advanceably and retractably into the center section of this agitation means 21. The metal material is heat melted by an external heat. The molten metal material is accumulated in the fusion vessel by homogenizing by the agitation means 21.

Abstract: The invention has an object to permit to make the accumulation amount and the temperature of molten metal in the metal material molding machine constant, by performing material supply and melting taking the accumulation amount as reference during the molding operation. The supply apparatus 11 and the agitation means 29 of metal material at the moment of operation starting are controlled to be inactive until the temperature of the melting vessel attains a predetermined value and to start operating when the predetermined temperature is attained, allowing to supply and agitate the metal material. The supply and the agitation of metal material after the predetermined temperature is attained, are performed while gradually supplying and agitating the metal material until metal material of at least 6 times or more of the maximum injection volume is accumulated in melt state.

Abstract: It is an object of the present invention to prevent oxidation during the metal melting, by suspending both heating and supply of metal material under the monitoring by measuring the oxygen concentration in the inactive gas atmosphere. A oxidation prevent method of melting metal material by a melting vessel 1 comprising inside a rotatable agitation member 8,having a weighing chamber 4 communicating with a nozzle member 2, and an injection member 9 advanceably and retractably inserting an extremity injection plunger 12 passing through the agitation member 8 in the weighing chamber 4, and the melting vessel being installed on a slant with the nozzle member 2 downside. The space area over the melted metal surface 15a of the melting vessel 1 is made into inactive gas atmosphere. The oxygen concentration in this space area is measured and monitored.

Abstract: There is provided an injection apparatus comprised of a heating cylinder which is closed by a front end member having a nozzle. The apparatus is further comprised of a plasticating screw in the heating cylinder in a freely rotating and reciprocating manner, and a plunger connected to the front end of the screw. The plunger has a conical front end in which flow channels are formed. The front end member has a measuring chamber formed therein at an internal central location thereof. The measuring chamber has a predetermined length and an internal diameter which is reduced by 8 to 15% with respect to an internal diameter of the heating cylinder. The diameter of the injection plunger is set almost equal to the diameter of the measuring chamber, whereby the injection plunger is inserted into the measuring chamber in a freely reciprocating manner.

Abstract: The invention has an object to permit to mold metal molds having a thixothropic structure by melting, agitating and weighing, injection molten metal in a melting vessel by combining separately functioning agitation means and injection means. The invention consists in supply granular metal material in a fusion vessel 11 having a weighing chamber 17 by a cylinder of required length communicating with a nozzle port at the extremity section, including rotatively an agitation means 21 inside, and wherein an injection means 22 whose extremity section is formed into an injection plunger 30 is inserted advanceably and retractably into the center section of this agitation means 21. The metal material is heat melted by an external heat. The molten metal material is accumulated in the fusion vessel by homogenizing by the agitation means 21.

Abstract: Upward variations of a molten metal level in a container for melting metallic material shall be carried out by detecting variations of a liquid level inside a detector connected to a gas-pipeline, wherein a rise in the pipeline pressure causes the liquid level to move down. Communication is established by means of a gas-pipeline 13 for inert gas between that portion of a container for melting metallic material which is above a molten metal surface 15a and that portion of a detector 16 comprising a transparent tubular container 18 which is above a liquid surface 17a. Variations of the liquid level 17a inside the detector 16 due to a rise in the pressure inside the above-mentioned gas-pipeline 13 are detected as upward variations of the level of the molten metal surface.

Abstract: A hydraulic circuit of an injection molding machine includes a 4-port servo valve having A, B, P, and T ports and adapted to drive and control an injection cylinder. The A and B ports are connected respectively to the front and rear oil chambers of the injection cylinder. The P port is connected to a hydraulic power unit. The T port is connected to an oil tank via a shutoff valve for selecting a regular mode or a differential mode. The T port is connected to the rear oil chamber via the logic valve. Alternatively, the rear oil chamber is connected to a hydraulic power unit side via the servo valve; the front oil chamber is connected to an oil tank via the shutoff valve; and the front oil chamber is connected to the P port of the servo valve via the logic valve. The above configuration eliminates or simplifies an additional braking circuit. Also, proper and accurate braking control can be performed.

Abstract: An injection apparatus for melted metals is provided to be capable of transferring the metals, melting them by the external heat, metering and degassing by employing a reservoir to reserve metals in liquid phase for the injection screw. The injection apparatus comprises a heating cylinder having a fore end portion which communicates with a nozzle member and of which internal diameter is made smaller to serve as a metering chamber, and an injection screw installed within the heating cylinder to be movable and rotational. A tip end of the injection screw is formed in a plunger having a diameter that can insert into the metering chamber with keeping a clearance for sliding. A reservoir, for reserving melted metals in liquid phase, consisting of an axis is provided between the plunger and a feeding portion containing screw flight around the axis.

Abstract: Low-melting point metallic material is designed to be able to melt with an inclined melting cylinder installed in the condition of combining an injection member with an agitating member therein, and a molten metal is designed to be able to weigh and inject by a plunger, whereby molding accuracy and efficiency can be improved more than a die-cast. A injection mechanism 2 is constituted by a melting cylinder 11 which a weighing chamber 17 communicating with a nozzle member 15 is provided on the inside of the tip, agitating and injection means provided in the combined condition in the melting cylinder so as to rotate or, advance or retreat freely and a device driving agitating and injection means, which is arranged on an rear-end side of the melting cylinder. The injection mechanism 2 is provided obliquely in a manner that a nozzle member side is directed in a downward direction to a mold-clamping mechanism 1.

Abstract: A mold clamping method for a straight hydraulic mold clamping apparatus, wherein supply of mold clamping oil to the rear oil chamber of the mold clamping cylinder starts immediately before completion of slowing down of the mold closing process using rapid-moving cylinders, and raising the mold clamping force successively starts simultaneously with completion of the mold closing.

Abstract: A method of operation for an injection molding machine is disclosed. The injection molding machine includes an injector having an advancable screw and a barrel cylinder, and a mold clamp for holding a mold with a controllable pressure and for allowing the mold to open a controllable amount. In performing the method, preset values are established for a stop position of the advancable screw, a clamping pressure of the mold clamp, and an opening amount for the mold. The screw is advanced up to the preset stop position and stopped thereat. The screw is controlled so as to ensure the location of the screw at the preset stop position for a preset time. Resin is injected from the barrel cylinder into the mold. The mold is clamped with the preset clamping pressure, during the preset time, by operating the mold clamp while maintaining the positioning of the screw at the preset stop position.

Abstract: A drive control apparatus connects a hydraulic source 4 and an oil tank 5 to an injection cylinder 2 through a servo valve 3 and controls the injection cylinder 2 by the servo valve 3. A first change-over valve 6 which is connected between the hydraulic source 4 and the servo valve 3 and has a large capacity. A flow limiting circuit 9 connects a throttle valve 7 to a second change-over valve 8 having a small capacity in series and is connected to the first change-over valve 6 in parallel. A change-over valve control portion 10 opens both the first change-over valve 6 and the second change-over valve 8 when controlling a large rate of flow in an injection process or the like and controls to close the first change-over valve 6 when controlling a small rate of flow in a pressure maintenance process or the like.

Abstract: A protecting apparatus of an injection molding machine having an injection of cylinder 2r with a built-in double rod type piston, and a servo valve for driving and controlling the injection cylinder includes a power failure detecting circuit for detecting a power failure, and a power-failure-time signal outputting circuit Ub for outputting a neutral signal, by which the servo valve is controlled at a neutral signal, by which the servo valve is controlled at a neutral position, to an instruction signal input line for the servo valve, due to the detection of the power failure by the power failure detecting circuit. A power-failure-time shutting down circuit is connection to the oil transferring line for supplying pressurized oil to the injection cylinder. The power-failure-time shutting down circuit includes a control valve for opening the oil transferring at the time of the non-power failure, and for shutting down the oil transferring line at the time of the power failure.