A method for increasing the injection speed of a melted plastic injection device for injecting said melted plastic into a molding cavity (51), said injection device comprising a first cylinder (1) provided with a tubular casing (2) defining a first inner diameter d.sub.1, and a first piston (3) slidable inside said tubular casing (2), adapted to be loaded with melted plastic and to inject said melted plastic toward the molding cavity (51); a second cylinder (21) constrained to the first cylinder (1) and provided with a second piston (23) which rod (24) is connected to the first piston (3) and is adapted to actuate said first cylinder (1) during an injection operation; the method comprising the steps of: —releasing second cylinder (21) and first cylinder (1) by extracting the first piston (3) from the tubular casing (2); —coaxially inserting a tubular body (12), defining a second inner diameter d.sub.3 which is smaller than the first inner diameter d.sub.1, into the tubular casing (2); —disconnecting the first piston (3) from the rod (24); —connecting a third piston (13) to the rod (24), said third piston (13) being sized to slide inside said tubular body (12); —constraining second cylinder (21) and first cylinder (1) by inserting the third piston (13) into the tubular casing (2).

A hot runner device includes a first block and a second block. A supply nozzle is connected to the first block. A nozzle unit is connected to the second block. The first block and the second block are connected to each other so as to be slidable relative to each other along the longitudinal direction of a hot runner block. First and second positioning pins are inserted into first and second insertion holes of the second block. The first insertion hole is larger than the second insertion hole.

A hot runner device includes a first block and a second block. A supply nozzle is connected to the first block. A nozzle unit is connected to the second block. The first block and the second block are connected to each other so as to be slidable relative to each other along the longitudinal direction of a hot runner block. First and second positioning pins are inserted into first and second insertion holes of the second block. The first insertion hole is larger than the second insertion hole.

A flow rate adjusting device includes a main body portion having a first opening portion to which a molten material is supplied, a second opening portion from which the molten material is discharged, a supply flow path communicating with the first opening portion and the second opening portion, and a cross hole intersecting the supply flow path; and a shaft-shaped valve portion disposed inside the cross hole. The valve portion has a tip end portion, a rear end portion, and a recessed portion provided between the tip end portion and the rear end portion and communicating with the first opening portion and the second opening portion, and the valve portion is rotated in the cross hole to change a position of the recessed portion, such that a flow path cross-sectional area of the supply flow path is changed to adjust a flow rate of the molten material discharged from the second opening portion; a storage chamber storing a part of the molten material flowing through the supply flow path between the first opening portion and the valve portion is defined by the tip end portion and an inner wall surface of the cross hole; the valve portion has a first contact surface provided between the recessed portion and the rear end portion and facing the rear end portion side; and the main body portion has a second contact surface to come into contact with the first contact surface from the tip end portion side.

An injection molding apparatus and method of fabricating a molded part are provided. The apparatus may include a barrel, a nozzle enclosing an end of the barrel and defining an opening in fluid communication with an inside of the barrel, and an extrusion screw positioned at least partially inside the barrel and rotatable relative to the barrel. The extrusion screw may include a screw tip. Relative axial movement between the barrel and the extrusion screw may open or close the opening of the nozzle to permit or prevent, respectively, material flow through the opening of the nozzle. The method may include clamping a mold, opening a nozzle, rotating the extrusion screw to pump a molten material into the mold until the mold is filled, closing the nozzle, and unclamping the mold to release a molded part.

An injection molding apparatus and method of fabricating a molded part are provided. The apparatus may include a barrel, a nozzle enclosing an end of the barrel and defining an opening in fluid communication with an inside of the barrel, and an extrusion screw positioned at least partially inside the barrel and rotatable relative to the barrel. The extrusion screw may include a screw tip. Relative axial movement between the barrel and the extrusion screw may open or close the opening of the nozzle to permit or prevent, respectively, material flow through the opening of the nozzle. The method may include clamping a mold, opening a nozzle, rotating the extrusion screw to pump a molten material into the mold until the mold is filled, closing the nozzle, and unclamping the mold to release a molded part.

A multi-layer nozzle for injection molding includes a nozzle housing, a valve stem, a stem guide, an insert, and a nozzle tip. The insert may comprise a 3D metal printed insert. In embodiments, a 3D metal printed insert may be configured to split and combine the flow of materials, which may form a multi-layered article, such as a preform. A method of using such a multi-layer nozzle to form articles is also disclosed.

In the present invention, sealing tape is wrapped around the outer circumferential surface of an introduced mold, and a monomer solution is injected into a cavity formed therein, wherein the injection amount of the monomer solution can be precisely controlled by using a vision recognition system. According to a preferable embodiment, a monomer solution of a monomer solution tank is suctioned, in advance, into a syringe capable of adjusting a capacity corresponding to a mold; most of the monomer solution, which has been injected into the syringe, is firstly injected into the mold at a high injection flow rate or injection speed; while the residual amount of the monomer solution is secondly injected at a reduced injection flow rate or injection speed, it is finally confirmed, by using a vision recognition system, whether the monomer solution is filled in the mold; and then injection is finished.

A device for producing components using an injection molding method includes at least one cavity (1a) for forming a respective product, at least one injection nozzle (3a) through which material is injected into the cavity (1a), a mold release (4), a distribution channel (10), a media supply (11), an exhaust air channel or return channel (12), at least one shut-off needle (6a). The shut-off needle is connected to a piston in a force-fitting or form-fitting manner and is inserted into the injection nozzle (3a). At least one valve (7a) for opening the needle (6a) and at least one valve (8a) for closing the needle (6a) are provided, such that the valve (7a) and the valve (8a) are arranged directly adjacent to the shut-off needle (6a). A control unit for the valve (7a) and the valve (8a) is also provided.

The invention relates to a device for producing a knee spacer component by curing bone cement paste. The invention also relates to methods for producing knee spacer components using such a device.