Abstract: The present invention provides a pressure casting method of a magnesium alloy. In the method, a molten magnesium alloy is cooled to form a partially molten state containing a solid-phase, and the partially molten state is further cooled to form a solid-phase granularly crystallized solid material. The solid material is partially-melted and pressure cast into a mold by a molding machine. A ratio of primary crystals in said solid material is set to 55 to 65%. The solid material is partially-melted in a solid-phase and liquid-phase coexisting state at a selected heating temperature so that a semi-solid having thixotropic properties and having the size of a main solid phase of 50 to 250 ?m and a solid-phase ratio of 30 to 70% is formed. The semi-solid is pressure cast into a mold through a nozzle while maintaining the semi-solid state to form metal products having a ratio of primary crystals of 20 to 50%.

Abstract: The present invention provides a pressure casting method of a magnesium alloy. In the method, a molten magnesium alloy is cooled to form a partially molten state containing a solid-phase, and the partially molten state is further cooled to form a solid-phase granularly crystallized solid material. The solid material is partially-melted and pressure cast into a mold by a molding machine. A ratio of primary crystals in said solid material is set to 55 to 65%. The solid material is partially-melted in a solid-phase and liquid-phase coexisting state at a selected heating temperature so that a semi-solid having a thixotropic properties and having the size of a main solid phase of 50 to 250 ?m and a solid-phase ratio of 30 to 70% is formed. The semi-solid is pressure cast into a mold through a nozzle while maintaining the semi-solid state to form metal products having a ratio of primary crystals of 20 to 50%.

Abstract: The present invention provides a pressure casting method of a magnesium alloy. In the method, a molten magnesium alloy is cooled to form a partially molten state containing a solid-phase, and the partially molten state is further cooled to form a solid-phase granularly crystallized solid material. The solid material is partially-melted and pressure cast into a mold by a molding machine. A ratio of primary crystals in said solid material is set to 55 to 65%. The solid material is partially-melted in a solid-phase and liquid-phase coexisting state at a selected heating temperature so that a semi-solid having a thixotropic properties and having the size of a main solid phase of 50 to 250 ?m and a solid-phase ratio of 30 to 70% is formed. The semi-solid is pressure cast into a mold through a nozzle while maintaining the semi-solid state to form metal products having a ratio of primary crystals of 20 to 50%.

Abstract: An injection molding apparatus of a metal material places a heating cylinder in an inclined position. The heating cylinder includes a nozzle at a tip thereof and a screw disposed inside. In this way, the metal material in a liquid phase state can be transferred and metered accurately in a reliable manner at all times by flowing due to the inclination and a transfer force produced by rotation of the screw. A clamping apparatus is provided to oppose the injection apparatus and includes a mold having a sprue bush inside. The injection apparatus and the clamping apparatus are placed on an apparatus platform in an inclined position at the same angle with the mold in a lower end, so that the metal material in the liquid phase state in the heating cylinder flows down toward the head due to self-weight. The nozzle and sprue bush are positioned on the same straight line, thereby maintaining nozzle touch without bending the nozzle.

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: A robot for a production machine including a rotation drive unit disposed on a support base; a first arm having a proximal end portion fixed to a rotary shaft of the rotation drive unit; a first proximal-side pulley disposed coaxially with the rotary shaft and fixed to the support base; a second proximal-side pulley fixed to a distal end portion of the first arm; an intermediate shaft rotatably supported on the distal end portion of the first arm and penetrating a center portion of the second proximal-side pulley; a first distal-side pulley provided integrally with the intermediate shaft; a first rotation transmission section for drivingly connecting the first distal-side pulley and the first proximal-side pulley; a second arm having a proximal end portion fixed to the intermediate shaft; a distal-side shaft rotatably supported on a distal end portion of the second arm; a second distal-side pulley provided integrally with the distal-side shaft; a second rotation transmission section for drivingly connecting t

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: An injection molding process wherein the times of heating to melt a resin are reduced to minimize the thermal hysteresis and to decrease the deterioration of physical properties caused by the thermal hysteresis, so that high quality information recording disks may be produced. A molding process wherein the plasticating and the injection and filling of a material resin are carried out in separate cylinders, allows constant molding for a long period of time. A material resin such as polycarbonate is supplied without predrying to an injection apparatus for a first time molding. Resin is kneaded by the apparatus while volatile components are heated to be vaporized and exhausted through a vent port. An inert gas atmosphere is provided within the cylinder to prevent the material resin from being oxidized. Since predrying can be dispensed with, the thermal hysteresis will be extremely small and the deterioration of the resin caused by such heating may be suppressed.

Abstract: To avoid generation of air bubbles and silver which otherwise may be caused due to forced retraction of a dwelling plunger after a dwelling cycle is completed. A dwelling cycle is performed at the same time of metering by using an injection machine 1 and a dwelling machine 2. The injection machine 1 comprises an injection screw 11 mounted in a heating cylinder 12. The dwelling machine 2 comprises a dwelling plunger 21 slidably mounted therein and faced to a resin passage 14. An advancing motion of the dwelling plunger 14 is limited to the side surface of the resin passage while a backward movement of the dwelling plunger is limited to a position at which a desired volume of a resin trap 26 is formed for the resin to be packed in the passage between the head of the plunger and the resin passage 14. The dwelling plunger 21 is allowed to be in a free state during an injection cycle or the metering.

Abstract: An injection apparatus capable of carrying out injection and filling of a resin and injection of a gas making use of an injection screw or injection plunger for the injection of a high-pressure gas comprises an injection screw 5 having a conical injection head 3 at the front end thereof and a ring valve 4 around a rear portion of the injection head, an injection cylinder the interior of a front end portion of which equipped with a nozzle member is formed as a tapered surface in accordance with the injection head 3 and can be closed by its contact with the injection head 3 and which contains the injection screw 5, gas flow passages 12 and 8 provided from the front end of the injection head 3 to a rear end portion of the injection screw 5, an opening/closing pin 17 inserted into the gas flow passage 12 in the injection head in such a manner that it can move together with a piston at the rear end of the injection head, and an actuation gas flow passage 10, provided inside the gas flow passage 8, for applying pre

Abstract: A die assembly for molding a disc such as a compact disc, a video disc or the like by employing an injection molding process. The die assembly comprises a stationary die half including as essential components a stationary platen, a base die half, and an insert die half received on the stationary platen, and a movable die half. The insert die half includes a first insert for fixing the insert die half on the stationary platen, and a first mirror surface board removably received in a cavity of the first insert. The insert die half can be easily installed and removed into/from an installation space defined by a pair of retaining members and a die receiving member and when installed, it can be certainly and easily fixed by a pair of retaining members.

Abstract: A disk substrate molding die is provided in which the quantity of eccentricity of a stamper can be reduced to a small value. The molding die includes a member having mounted thereon a thin plate (19) carrying thereon a recorded transfer signal and an adjusting device consisting of a plurality of pairs of adjusting blocks, each formed of movable blocks (9a) and (9b) and blocks (10a) and (10b) having adjacent surfaces inclined in the moving direction of the movable blocks and common to one another.

Abstract: This invention relates to a work bed for a grinding apparatus provided with a work table (9) which moves in a direction of X-axis and in a direction of Y-axis, comprising X-axis and Y-axis set to an upper surface of the work table (9), and a conductive dresser member (13) and a measuring reference member (14) provided on the upper surface of the work table (9) with operating surfaces thereof being parallel with the X-axis or Y-axis.

Abstract: This invention relates to a composite processing machine designed so as to be movable in a longitudinal and lateral direction on the side of a work table so that cutting process, discharge process, electrolytic grinding process and the like may be accomplished by a single machine, comprising means for moving a work table (1) on a machine bed (2) in a direction of x-axis and y-axis, a processing unit (9) having a chuck (14) capable of being detachably engaged with various tools and a discharge electrode at the fore end of a spindle (1) positioned upwardly of the work table (1) and comprising a motor (15) for rotating spindle and a fixing brake (12), means for moving a processing unit (9) in a direction of z-axis, an auto tool changer (18) for holding a cutting tool, a discharge electrode, a measuring probe, a grinding wheel and the like to selectively feed them to the chuck, and a processing power source (22) connected over a discharge electrode (26) or a grinding wheel (51) mounted on the chuck (14) and a wor