US-12617133-B2 - Injection mold and method for manufacturing injection-molded parts

US12617133B2US 12617133 B2US12617133 B2US 12617133B2US-12617133-B2

Abstract

An injection mold for manufacturing injection-molded parts by injecting injection molding material into a cavity having a contour corresponding to the injection-molded part to be manufactured. The injection mold includes a distribution channel for injection molding material which is connectable to an injection nozzle and is in communicative connection with the cavity. The distribution channel includes a compensating volume region having a volume, determined by the type and number of cavities connected to the distribution channel, for accommodating injection molding material during the injection molding process.

Inventors

Sebastian Weber
Sebastian Meyer

Assignees

WAGO VERWALTUNGSGESELLSCHAFT MBH

Dates

Publication Date: 20260505
Application Date: 20231121
Priority Date: 20221123

Claims (14)

1 . An injection mold for manufacturing injection-molded parts by injecting injection molding material into cavities each having a contour substantially corresponding to a respective one of the injection-molded parts to be manufactured, the injection mold comprising: a distribution channel for injection molding material which is connectable to an injection nozzle and is in communicative connection with each of the cavities; a compensating volume region provided for the distribution channel, the compensating volume region having a compensating volume determined by a type and number of the cavities connected to the distribution channel to accommodate injection molding material during the injection molding process, wherein the compensating volume region is branched off of a section of the distribution channel, such that as the injection molding material flows through the section of the distribution channel, a portion of the injection molding material flows into the compensating volume region and is maintained in the compensating volume region, while a remaining portion of the injection molding material continues to flow through the section of the distribution channel.
2 . The injection mold according to claim 1 , wherein the compensating volume region has a receiving opening, wherein different compensation inserts are provided, which are each selectively insertable into the receiving opening, each of the compensation inserts having an indentation which communicates with the distribution channel to provide the compensating volume, and wherein the indentations of the different compensation inserts have different volumes, such that the compensating volume is modifiable based on a selection of one of the compensation inserts to be inserted into the receiving opening.
3 . The injection mold according to claim 2 , wherein each of the compensation inserts have an end-face side provided with the indentation, the end-face side having a radially outwardly leading groove merging into the indentation, and the distribution channel being communicatively connectable to the indentation via the groove when a respective one of the compensation inserts is inserted into the receiving opening of the injection mold.
4 . The injection mold according to claim 3 , wherein each of the compensation inserts has a single opening for flow of the injection molding material, wherein the groove forms the single opening.
5 . The injection mold according to claim 2 , wherein the compensation inserts are cylindrical.
6 . The injection mold according to claim 2 , wherein the indentations of the compensation inserts have different diameters.
7 . The injection mold according to claim 2 , wherein the compensation inserts have at least two different outer diameters, and wherein the injection mold includes at least two compensating volume regions, and wherein the receiving opening of each of the at least two compensating volume regions has a diameter that is determined by the cavities to accommodate a respective one of the compensation inserts to provide the compensating volume.
8 . The injection mold according to claim 1 , wherein two or more of the cavities are provided and are connected to the distribution channel, and the distribution channel is in communicative connection with the compensating volume, and wherein a position of the compensating volume with respect to one of the cavities, and a size of the compensating volume being determined by a combination of the cavities.
9 . The injection mold according to claim 1 , wherein the compensating volume region, as a branch, is connected to the distribution channel in a region of a transition of the distribution channel into an associated one of the cavities.
10 . The injection mold according to claim 1 , wherein for at least one cavity of the cavities connected to the distribution channel, the compensating volume is connected to the distribution channel adjacent to a transition of the distribution channel into the at least one cavity.
11 . The injection mold according to claim 1 , wherein the injection mold has an injection molding material distribution unit with a nozzle-side mounting frame and an ejection-side mounting frame, the nozzle-side mounting frame and/or the ejection-side mounting frame being designed for accommodating mold inserts having the cavities, and the distribution channel with the compensating volume region being introduced into the mold inserts or into the nozzle-side mounting frame and/or the ejection-side mounting frame.
12 . The injection mold according to claim 1 , wherein the distribution channel directs the injection molding material to all of the cavities provided in the injection mold.
13 . A method for manufacturing injection-molded parts using the injection mold according to claim 1 , the method comprising: introducing the compensating volume region into the injection mold, the compensating volume region being in communicative connection with the distribution channel and for accommodating injection molding material, the compensating volume region having the compensation volume that is adapted to the type and number of the cavities connected to the distribution channel, wherein the compensating volume region is introduced into the injection mold so as to be branched off of the section of the distribution channel, such that as the injection molding material flows through the section of the distribution channel, the portion of the injection molding material flows into the compensating volume region and is maintained in the compensating volume region, while the remaining portion of the injection molding material continues to flow through the section of the distribution channel.
14 . The method according to claim 13 , further comprising: selecting compensation inserts from a set of different compensation inserts that provide various compensation volumes such that a position and size of the compensation volume is adapted to the type and number of the cavities connected to the distribution channel; and inserting the selected compensation inserts into respective associated receiving openings in the compensating volume region of the injection mold.

Description

This nonprovisional application claims priority under 35 U.S.C. § 119(a) to German Patent Application No. 10 2022 131 019.1, which was filed in Germany on Nov. 23, 2022, and which is herein incorporated by reference. BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to an injection mold for manufacturing injection-molded parts by injecting injection molding material into a cavity having a contour corresponding to the injection-molded part to be manufactured, the injection mold having at least one distribution channel, for injection molding material, which is in communicative connection with the cavity. The invention further relates to a method for manufacturing injection-molded parts using such an injection mold. Description of the Background Art For the economical mass production of molded parts, in particular plastic molded parts, using injection molding, injection molding machines are used which have an injection unit, designed to prepare raw material and inject the injection molding material under pressure into an injection mold, and a closing unit that receives the injection mold and is provided for opening and closing. The injection unit generally has a worm shaft which is rotatably guided in a cylinder, and which in the rear area has a granule inlet, and at the front, free end has a machine nozzle. The injection molding material that is melted in the worm is injected under pressure through the machine nozzle and into the injection mold. The closing unit has a nozzle-side fixed platen that is situated vertically on a machine frame and that bears a nozzle-side mold half. In addition, the closing unit has an oppositely situated fixed platen that is movable, generally hydraulically, in the direction of the stationary fixed platen, and that bears an ejection-side mold half of the injection mold. By use of such an injection mold half, two mold halves are moved toward one another so that their surfaces are very close together. At least one cavity having a shape that is adapted to the injection-molded part to be manufactured is then present in the overlaid surfaces. At the ejection-side mold, an ejection mechanism is then present which includes at least one plunger for pushing the manufactured injection-molded part out of the cavity. However, the ejection mechanism may have even further parts, for example for creating undercut contours. The nozzle-side mold half may have, for example, a connection to a heating channel manifold having the associated heating channel nozzle. DE 10 2011 056 694 B4, which corresponds to US 2014/0175690, which is incorporated herein by reference, and which discloses an injection mold in which mold insert halves of at least one mold insert are fitted into slide-in frames, and the slide-in frames are connectable to one another to form a slide-in module that is removable from the frame tool. A nozzle-side slide-in frame has at least one nozzle opening for receiving at least one associated injection molding nozzle of the injection molding material distribution unit, which is situated at the first nozzle-side mold half. In this way, the nozzle-side and ejection-side mold halves together with the mold inserts fitted therein may be removed as a whole from the injection molding machine as a customized mold block when retrofitting the fixed platens. EP 2 464 501 B1 discloses an injection mold having inlet channels for the inflow of injection molding material. Provided in the inlet channel are compensation chambers which ensure a uniform distribution of the injection molding material over a rubber sole of a shoe. Possible differences in the volume of the rubber profile are automatically compensated for, and/or the quantity of the injected material is automatically metered. EP 0 666 791 B2, which corresponds to U.S. Pat. No. 6,019,935, describes a method for injection molding of molded parts made of thermoplastic material and whose walls enclose a hollow space, wherein the molten plastic is injected in a predetermined amount into the cavity of a mold, during and/or upon which a fluid pressure medium, in particular 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. For the targeted control of the wall thickness distribution and to ensure that in each case only the volume of thermoplastic material that is needed to manufacture the molded part in question is injected into the cavity or the mold nest of the mold, the pressure medium is fed into the cavity and into the molten plastic, at first essentially only in the flow direction of the molten plastic. For this purpose, hollow needles for feeding in the pressure media are stationarily installed in the mold, or with their free ends continuously protrude into the mold nest or the cavity, or are temporarily displaceable up to the mold nest or the cavity. The hollow needles are inserted at various locations in the cavity. E