Abstract: The invention relates to a method for the injection moulding of plastic parts from thermoplastic material. To produce stable plastic parts with a low density, the method comprises the steps: a) Production of thermoplastic melt; b) Adding of a fluid to the thermoplastic melt; c) Mixing of the thermoplastic melt containing the fluid; d) Providing of an injection moulding tool with a cavity, wherein the volume of the cavity of the injection moulding tool is expandable from an initial volume to an end volume; e) Heating of at least a part of the walls of the cavity; f) Injection of the mixture from thermoplastic melt and gas into the cavity, wherein the volume of the cavity takes the initial volume; g) Expansion of the volume of the cavity; h) Cooling of at least a part of the walls (9) of the cavity; i) Demoulding of the injection moulded plastic part after the plastic melt is at least partially solidified.

Abstract: The moulded part has at least two different sections with different outer diameter and a void inside the moulded part. To make the void, a projectile is passed through the still molten injection mouldable material in a direction of flow. A pressurized fluid is exerted in the void in the direction of flow behind the projectile to move the projectile. To obtain constant wall thicknesses, the projectile has at least one elastic or plastic section, which is delimited by a space in which the pressurized fluid can enter. The volume of the space and the effective outer diameter of the projectile can be changed by the fluid pressure and is controlled in such a manner that the space and the effective outer diameter of the projectile is enlarged and/or reduced to make the moulded part with different diameters.

Abstract: The invention relates to a device for the injection moulding of a moulded part (2) comprising a void (1), wherein a projectile (10) can be positioned at a fluid injection nozzle (8) in the region of a fluid aperture (9), which projectile (10) can be caused to flow in the direction of the longitudinal axis (L). To allow the production of moulded parts with enclosed voids in a better way the invention is characterized in that the fluid injection nozzle (8) comprises a section (11) entering into a cavity (5) of a mould, which section (11) is free from any undercut in a direction (E) of insertion of the fluid injection nozzle (8) into the cavity (5), wherein an angle (?) is arranged between a longitudinal axis (L) and the direction (E) of insertion.

Abstract: The invention relates to a method for injection moulding of a moulded part (1), which has at least two different sections (2, 3) being different in the outer diameter (D1, D2), wherein a void (4) is produced in the inner of the moulded part (1) by causing a projectile (5) in the direction of a longitudinal axis (L) of the moulded part (1) through the still molten injection mouldable material in a direction of flow (F), whereto a pressurized fluid is exerted in the void (4) in the direction of flow (F) behind the projectile (5) which moves the projectile (5) into the direction of flow (F).

Abstract: The invention relates to a device for the injection moulding of a moulded part (2) comprising a void (1), wherein a projectile (10) can be positioned at a fluid injection nozzle (8) in the region of a fluid aperture (9), which projectile (10) can be caused to flow in the direction of the longitudinal axis (L). To allow the production of moulded parts with enclosed voids in a better way the invention is characterized in that the fluid injection nozzle (8) comprises a section (11) entering into a cavity (5) of a mould, which section (11) is free from any undercut in a direction (E) of insertion of the fluid injection nozzle (8) into the cavity (5), wherein an angle (?) is arranged between a longitudinal axis (L) and the direction (E) of insertion.

Abstract: Device and process for injection molding of molded parts made from plastic material having at least one cavity, which has means for injecting plastic melt into the cavity of an injection-molding die along a melt flow path and means for injecting a fluid into the still molten plastic material, wherein the means for injecting a fluid are designed in order to inject a liquid at preset pressure and preset quantity. Provision is made in that the means for injecting a liquid includes a first part element, which is arranged centrally and remote from the injection-molding die and supplies at least one injection-molding die, and includes at least one second part element, which is arranged in the immediate vicinity of the injection-molding die, and a third part element, which is arranged locally on the injection-molding die at least during injection of the liquid.

Abstract: The invention relates to a method and an apparatus for injection molding thermoplastic molded parts, having at least one cavity. The method comprises the following steps: a) injecting thermoplastic melt from an injection unit along a melt flow path into the cavity of an injection molding tool; b) injecting a fluid into the still liquid plastic material, so that the plastic material is pressed against the walls of the cavity; c) allowing the plastic material to cool until it forms the self-supporting molded part; and d) removing the molded part from the cavity of the injection molding tool.

Abstract: A process for injection molding of molded parts made from thermoplastic plastic material having at least one cavity, which includes: a) injection of thermoplastic plastic melt from an injection unit along a melt flow path into the cavity of an injection-molding die; b) injection of a fluid into the still molten plastic material, so that the latter is pressed against the walls of the cavity; c) allowing the plastic material to cool until the latter forms the molded part in self-supporting manner; and d) releasing the molded part from the cavity of the injection-molding die.

Abstract: A method for the multi-component injection molding of plastic parts, in which at least two different plastic components are injected into an injection molding tool to form a plastic part, the method comprising the following steps: a) introducing a first plastic component into a melt accumulation chamber, which is bounded by a piston-like end section; b) subsequently introducing a second plastic component into the melt accumulation chamber; c) transferring plastic melt accumulated in the melt accumulation chamber into the injection molding tool. In one embodiment the pressure conditions in the cavity region are homogenized. For this purpose the invention specifies that, when the plastic melt is transferred in accordance with the above step c), the piston-like end section of the melt accumulation chamber is moved in such a way that it forms part of the cavity wall of the injection molding tool.

Abstract: Device and process for injection molding of molded parts made from plastic material having at least one cavity, which has means for injecting plastic melt into the cavity of an injection-molding die along a melt flow path and means for injecting a fluid into the still molten plastic material, wherein the means for injecting a fluid are designed in order to inject a liquid at preset pressure and preset quantity. Provision is made in that the means for injecting a liquid includes a first part element, which is arranged centrally and remote from the injection-molding die and supplies at least one injection-molding die, and includes at least one second part element, which is arranged in the immediate vicinity of the injection-molding die, and a third part element, which is arranged locally on the injection-molding die at least during injection of the liquid.

Abstract: A process for injection molding of molded parts made from thermoplastic plastic material having at least one cavity, which includes: a) injection of thermoplastic plastic melt from an injection unit along a melt flow path into the cavity of an injection-molding die; b) injection of a fluid into the still molten plastic material, so that the latter is pressed against the walls of the cavity; c) allowing the plastic material to cool until the latter forms the molded part in self-supporting manner; and d) releasing the molded part from the cavity of the injection-molding die.

Abstract: The invention relates to a method and an apparatus for injection molding parts, which comprises a mixture of at least one plastic material and at least one additive in the form of fibrous or powdered fillers or reinforcement materials.

Abstract: A method for injection molding plastic molded parts from thermoplastic, comprises the following steps: the production of a thermoplastic melt (1) through the rotation of a plasticizing and injection screw (2) in a preplasticizing cylinder (3); the addition to the thermoplastic melt (1) of a fluid (4) by introducing the fluid (4) into the preplasticizing cylinder (3); the mixing up the thermoplastic melt (1) to which the fluid (4) has been added, through the rotational motion of the plasticizing and injection screw (2); the injection of the mixture of thermoplastic melt (1) and fluid (4) into the cavity (8) of an injection molding tool (5).

Abstract: The invention relates to a method for injection molding a plastic molded part in an injection mold, comprising a) injecting a specified amount of plastic melt into the injection mold; b) introducing a compressed fluid between a part of the wall of the injection mold and the injected plastic melt; c) allowing the plastic melt to cool until the plastic molded part is self-supporting; and d) removing the plastic molded part from the mold. The invention specifies that, during or after step a) and during or before step b), the cavity of the injection mold is sealed against the environment, preferably by activating at least one seal.

Abstract: A process and a device for the injection molding of plastic objects of thermoplastic, duraplastic, or elastomeric material implements the steps of: a) injecting a sufficient quantity of molten plastic into cavity (2) of a mold (1) along a melt flow path, which extends from a unit (4,5) for plasticizing and injecting the plastic through a plastic injection nozzle (3) into mold (1); b) introducing a pressurized fluid, particularly a pressurized gas, from a wall (7) of cavity (2) through at least one fluid injection element (6), so that a fluid blanket (8) forms between wall (7) of cavity (2) and the plastic introduced into the mold; c) allowing the molded part thus produced to harden; d) relieving the cavity (2) of the pressure of the pressurized fluid; and e) demolding the molded part. It is provided according to the invention that at least one surface projection (9) is provided in the mold (1), on the cavity wall (7), such that its upper plateau (10) runs extensively parallel to the cavity wall (7).

Abstract: The invention relates to a method and an apparatus for injection molding thermoplastic molded parts, having at least one cavity. The method comprises the following steps: a) injecting thermoplastic melt from an injection unit along a melt flow path into the cavity of an injection molding tool; b) injecting a fluid into the still liquid plastic material, so that the plastic material is pressed against the walls of the cavity; c) allowing the plastic material to cool until it forms the self-supporting molded part; and d) removing the molded part from the cavity of the injection molding tool.

Abstract: A method and an apparatus are disclosed for producing plastic objects with solid regions and hollow regions. The method has the following steps: a) blocking off a part of the cavity (2) of a molding tool (1), so that little or no plastic melt can reach the blocked-off region (8); b) injecting plastic melt into the unblocked region (9) of the cavity (2) of the molding tool (1); c) releasing the blockage, so that plastic melt can reach the previously blocked-off region (8) of the cavity (2); d) injecting a pressurized gas into the melt by means of at least one fluid injection nozzle (7), so that the melt injected into the molding tool is distributed into the desired regions of the cavity (2) while forming a hollow space and is pressed against the cavity walls of the molding tool (1); e) allowing the molded part (6) to cool; f) relieving the cavity (2) of the pressure of the pressurized fluid; and g) demolding the molded part.

Abstract: An apparatus and method provides that before, during, and/or after the plastic objects have been injection molded, a portion of the first plastic component, the second material, and/or a mixture of the two components is conveyed to at least one storage element with a variable volume. This element adjoins the flow path of the material melt. After completion of the injection molding process of the plastic objects and/or before the material is injected for the next plastic object to be produced, the plastic or the material stored in a storage element with a variable volume is conveyed to the flow path of the melt of the plastic or material. This frees the melt flow path of a mixture of the two plastic components and/or obtains a desired material mixture for producing the next plastic object.

Abstract: A method and an apparatus are disclosed for producing plastic objects with solid regions and hollow regions. The method has the following steps: a) blocking off a part of the cavity (2) of a molding tool (1), so that little or no plastic melt can reach the blocked-off region (8); b) injecting plastic melt into the unblocked region (9) of the cavity (2) of the molding tool (1); c) releasing the blockage, so that plastic melt can reach the previously blocked-off region (8) of the cavity (2); d) injecting a pressurized gas into the melt by means of at least one fluid injection nozzle (7), so that the melt injected into the molding tool is distributed into the desired regions of the cavity (2) while forming a hollow space and is pressed against the cavity walls of the molding tool (1); e) allowing the molded part (6) to cool; f) relieving the cavity (2) of the pressure of the pressurized fluid; and g) demolding the molded part.

Abstract: Proposed is a process for injection molding of products (1) made of thermoplastic material, whose walls (2) enclose a hollow space (3), wherein the molten plastic is injected in a predetermined amount into the cavity or molding nest (6) of a mold (5), during and/or upon which a fluid pressure medium (gas) is applied so that with the formation of the hollow space the molten plastic is distributed along and set against the walls of the cavity or molding nest. The pressure medium (gas) is fed into the cavity or molding nest (6) and into the molten plastic at first essentially only in the direction of flow of the molten plastic and in a quantity and/or at a pressure that causes a void (8) to form within the molten plastic, terminating at a distance from the end of the flow path.