DE102009031397A1 - Method for manufacturing cover part in injection-molded plastic die, involves uniformly injecting plastic mass from injection ducts in colors to manufacture cover parts in injection-molded plastic die, respectively - Google Patents

Abstract

The method involves filling multiple hot runner injection ducts (5, 6) with a plastic mass of different colors. Injection-molded plastic parts i.e. cover parts, are manufactured in an injection-molded plastic die (1) by uniformly injecting the plastic mass from the injection ducts in the colors, respectively. Gate marks (7, 8) of the injection ducts are homogeneously arranged with respect to a symmetry line of an injection-molded piece. The gate marks are provided in the injection-molded plastic die, where the die is divided into two die halves (2, 3).

Description

The The invention relates to a method for producing a plastic injection molded part in one having several Anspritzkanäle Plastic injection mold, wherein at least two Anspritzkanäle filled with plastic material of different colors.

One such method is for example to carry out a two-component injection method known. This is a Part of the mold initially closed by a slide and only in a second injection then a second portion, often with a plastic of other quality, for example a soft plastic when the first injection molding with a hard plastic was carried out, trained. Furthermore, it is also common after a first plastic injection process, the section thus produced in the form, or to put in another form um, then the second component, which is also in another color can be given to inject.

Furthermore, it has already been proposed with regard to a rational process in the production of plastic injection molded parts in different colors, see, for example DE 198 57 053 B4 in that the spray material in the injection channel, ie in the flow direction downstream of the injection unit, is first provided with paint, particles or optically active additives.

outgoing from the aforementioned prior art, the invention the object of specifying a method for producing a plastic injection molded part, with which in a rational way plastic parts of different Color can be produced.

These Task is according to a first solution solved in the subject matter of claim 1, with it being turned off is that a first plastic injection molded part by injecting a Plastic mass from one of the multiple Anspritzkanäle uniformly is made in one color and that then another plastic injection part in the same plastic injection mold by injection from another Anspritzkanal is produced uniformly in a different color. The invention thus exploits the fact that in a plastic injection mold, as used in two- or multi-component injection molding is, two or more Anspritzkanäle are present with which alternatively the same plastic injection mold completely can be filled. However, here is no displacement a manufactured after a first injection molding plastic part or a deporting of a molding area in the course of a first injection performed. Rather, for the production of plastic injection molding each used the entire plastic injection mold. While a first plastic injection molded part in a first color uniformly is prepared, is due to the second Anspritzkanals also Plastic injection compound in another color is ready, however not used for the production of this first plastic injection molded part. Rather, the second Anspritzkanal for the production a possibly desired second - different-colored - plastic injection molded part (only) used. During the production of such a second Although plastic injection part is also due to the first Anspritzkanals Plastic injection in the first color ready, but is in appropriate Way now not used.

This procedure can also be used in systems which also use known spraying methods under the name sandwich plastic injection method. This is about on the EP 419 911 A2 or the WO 97/44172 directed. In this embodiment, multiple injection channels provide the same gate. In contrast to the usual procedure in the aforementioned sandwich plastic injection method, however, only a uniform mass, at least in the amount required for complete injection of a part, is always introduced into the injection cylinder.

below Other features are explained that are independent or also in connection with the already explained claim concept or only partially with features of the explained claim concept Meaning.

So is first preferred that for the preparation of the first or further plastic injection part in each case only one of the plurality Anspritzkanälen is used. basically, for example, if there are three injection ports, could also be two Anspritzkanäle already at the Manufacture of a first plastic injection molded part are used, however, a further Anspritzkanal only when producing another plastic injection molded part.

Farther It is preferred that the Anspritzkanäle hot runner Anspritzkanäle are. This allows a particularly trouble-free change to reach another color.

It is also preferred that the injection channels, which are each connected to a separate injection unit in the form of an extruder and / or piston unit, open close to each other in the plastic injection mold. Alternatively, it is also preferred that only one orifice, such as in devices with which the aforementioned sandwich plastic injection method is feasible, are provided. In the case of multiple orifices, therefore, the first and second, so different in color parts need only insignificantly visually distinguished from the injection point used in their preparation. On the other hand, the parts generally have formations, possibly very slight formations, which reveal the two or more injection channels in the injection mold used. On the other hand, it is not absolutely necessary or preferred for the mouths to be close together. Rather, it can also be important to find technically equivalent injection points. In terms of filling the mold cavity about equivalent points. In this respect, it may be important that the injection points lie along an axis of symmetry of the injection molding.

If also before and below the production in terms of color different each complete plastic injection parts but it is also possible using the described principle, the same mold cavity area due to several in this from the cavity area emanating Injection channels with plastic injection compound different Coloring - at a first and a second part - too fill, a principle in two-component injection molding manufactured plastic injection molded part using this principle manufacture. For example, one in a second component Welch plastic sealing lip molded on a hard plastic base part in a first such two-component plastic injection molded part in a first color and in a second such two-component plastic injection-molded part be formed in a second color, while the hard plastic base part has the same color in both plastic injection molded parts. About that In addition, of course, according to the described here Process then as desired, in the example given, also the Color of the hard plastic base part from the first to the second plastic injection molded part be changed.

In the following, the invention will be explained further with reference to the attached drawing, which, however, represents only one embodiment. Hereby shows:
The single figure schematically shows a plastic injection mold as it can be used in the described method.

Shown and described is a plastic injection mold 1 , in a conventional manner in two mold halves 2 . 3 is divided. The mold cavity 4 is on the two mold halves 2 . 3 distributed. In one of the mold halves, in the embodiment of the mold half 2 , Are several, namely in the embodiment of two hot runner injection channels 5 . 6 provided, which in the mold cavity 4 open in a known manner.

It could also each have a hot runner Anspritzkanal 5 be provided in the mold half 2 is formed and another, in the mold 3 is trained.

In the hot runner injection channel 5 For example, plastic red color is maintained while in the hot runner Anspritzkanal 6 Plastic yellow color is kept. Both hot runner injection channels 5 . 6 are each connected to an extruder injection unit, not shown.

at the plastic injection molded part may be in the embodiment for example, to act a lid part.

If now a large number of red cover parts are to be produced, the gating is only effected via the hot runner injection channel 5 performed. If parts of yellow color are then to be produced, the gating is effected via the hot runner injection channel 6 performed.

In the plastic injection molded sprue 7 . 8th can be provided close to each other.

With the same plastic injection mold 1 So either red and yellow parts can be produced in any quantity. A conversion is not required. Since no color can remain in Zuführwegen and therefore must first be processed, it can not or practically come to rejects practically because of the color change.

All disclosed features are essential to the invention (in itself). In the disclosure of the application is hereby also the disclosure content the associated / attached priority documents (Copy of the advance notice) fully included, too for the purpose, features of these documents in claims present Registration with. The subclaims characterize in its optional sibling version stand-alone inventive development of the prior art, in particular to make divisional applications based on these claims.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 19857053 B4 [0003]
• - EP 419911 A2 [0006]
• WO 97/44172 [0006]

Claims (7)

Method for producing a plastic injection molded part in a plastic injection mold having a plurality of injection ports, each of which is connected to its own piston and / or extruder injection unit, wherein at least two injection ports are filled with plastic material of different colors, characterized in that a first plastic injection molded part by injection a plastic material from one of the plurality of Anspritzkanäle is uniformly produced in one color and that thereafter another plastic injection molded part in the same plastic injection mold is made by injection from a further Anspritzkanal uniformly in a different color. Method according to claim 1 or in particular according thereto characterized in that for the production of the first or further Plastic injection part in each case only one of the plurality of Anspritzkanäle is used. Method according to one or more of the preceding Claims or in particular according thereto, characterized that the Anspritzkanäle hot runner Anspritzkanäle are. Method according to one or more of the preceding Claims or in particular according thereto, characterized that the gate marks of the injection channels are close to each other. Method according to one or more of the preceding Claims or in particular according thereto, characterized that the sprues of the Anspritzkanale with respect to a symmetry line of a Springs are arranged equally. Method according to one or more of the preceding Claims or in particular according thereto, characterized that each Anspritzkanal provides in a gate assigned to him. Method according to one or more of the preceding Claims or in particular according thereto that several Anspritzkanäle provide in the same gate.

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