DE102010000798A1 - Lining part for use in inner space of passenger car to support e.g. covers, has cap-shaped circulating supporting edge provided between bearing pivot and lining part in transition region, where edge is arranged on non-visible rear part - Google Patents

Abstract

The part (1) has a cylindrical-shaped hollow bearing pivot (4) provided in a visible surface (2). A plastic injection molding body is provided as one-piece construction, where the lining part is made of plastic material. A cap-shaped circulating supporting edge is provided between the pivot and the lining part in a transition region. The edge is arranged on a non-visible rear part of the lining part. A circulating inner rear section is formed in a region of the edge. An aperture is formed in a cavity of the pivot. A support rib is formed between the edge and the rear part. An independent claim is also included for a method for manufacturing a lining part.

Description

The invention relates to a trim part in a vehicle interior made of plastic in one-piece construction with a protruding from the visible surface of the trim panel bearing pin for the storage of pivoting accessories and a method for its preparation.

For the storage of hinged accessories, such as storage compartments, covers, etc. on trim parts, it is necessary on the one hand to provide a certain stability, so that the bearing pin does not break off or kink under normal load. On the other hand, the visible surface of the trim part is not subject to optical compromises, i. H. It must be able to be produced in a consistently high optical quality.

At the same time it is extremely difficult to produce in the usual way for the production of trim parts plastic injection molding processes areas with different wall thicknesses and this possibly also with complex geometry of the part.

So far, the trim panel without bearing journals were first prepared and then attached as a separate part later, z. B. by welding.

However, this approach is undesirable because of the number of processing steps and effort, especially in the area of car manufacturing, where extremely efficient processes are required.

From the DE 42 04 627 C2 is a bearing axis for sun visors of vehicles, which is designed as a tubular hollow body with at least one bend and consists of a one-piece plastic injection molded body known. The tubular hollow body has an uninterrupted tube wall.

• a) in den Hohlraum einer geschlossenen Form eine vorbestimmte Menge einer Kunststoffschmelze eingespritzt wird,
• b) in die Schmelze Gas mit einem solchen Druck eingebracht wird, dass sich die Schmelze unter Bildung des Lagerachsenhohlraums gleichmäßig über die Oberfläche des Formhohlraums verteilt,
• c) nach einer Abkühlzeit die Form geöffnet und der hohle Formkörper der Form entnommen wird,
• d) vom Formkörper die geschlossenen Endverschlüsse abgetrennt werden.

The method for producing the bearing axis comprises the steps:

• a) a predetermined amount of a plastic melt is injected into the cavity of a closed mold,
• b) gas is introduced into the melt at a pressure such that the melt distributes uniformly over the surface of the mold cavity to form the bearing axis cavity,
• c) after a cooling time the mold is opened and the hollow molded body is removed from the mold,
• d) are separated from the molded body, the closed end closures.

However, so only the journal can be produced per se and this has a continuous substantially uniform wall thickness.

From the EP 0289 230 A2 For example, there is known a method of making plastic moldings wherein molten thermoplastic material is introduced into a mold cavity, gas is introduced into the plastic under pressure, and the plastic mold is allowed to cool in the cavity and allowed to cure while the gas is held under pressure for producing molded parts with unevenly distributed, thick-walled areas, which are connected to at least one inlet for supplying the pressurized gas, wherein the cavity is completely filled with plastic, and after filling and while the plastic is cooling and shrinkage tendency within the molded part, the gas under pressure in the plastic, which is located within the cavity, is introduced, wherein the gas flows only within the, the thick-walled areas forming plastic and the immediately adjacent zones of the molding, wherein the gas in the dic kinkigen areas penetrates and wherein the shrinkage of the plastic is canceled, and that the gas is left within the gas-filled areas during the Abkühlstadiums the pressing operation under pressure until the molding independently can maintain the shape that is predetermined by the cavity surface.

From the DE 198 27 706 C2 is a method for attaching a soft cover material to an injection molded plastic hard part with a hollow bent back plastic hard part section known with the steps:
Placing a cover material in a mold cavity between the mold halves of an injection mold;
Incomplete closing of mold halves;
Injecting thermoplastic resin into the mold cavity when the mold is incompletely closed against the masking material;
further closing of the mold halves with distribution of the injected resin in the mold cavity on the cover material; and
injecting a pressurized gas into the bent-back portion of the molded plastic part, distributing the resin in the bent-back portion and forming a hollow hard plastic portion.

The object of the invention is in contrast to provide a cowling with integral journal in one-piece construction by injection molding, which is inexpensive to produce and at the same time the bearing pin while a high Stability with low material usage.

This object is achieved by the trim part specified in claim 1.

The fact that the trim part consists of a plastic injection molded body in one-piece design, it is inexpensive to produce. Since it has a peripheral support edge in the region of the transition between the journal and the rest of the lining part, wherein the support edge is arranged on the invisible back of the trim part and the bearing pin is hollow, on the one hand a high stability can be achieved while economical use of materials. The visible surface is provided in the required quality. The support edge may be suitably designed so that it receives the forces acting on the bearing pin forces and introduces a large area in the fairing part by a suitable construction.

In this case, the support edge may have a greater wall thickness and / or a larger diameter than the bearing pin. Furthermore, the support edge may also be conical, both in terms of wall thickness and in terms of its diameter.

Preferably, the cavity is formed substantially cylindrical. This results in a lighter, more stable and with little material producible bearing pin.

Advantageously, a circumferential inner undercut is formed in the region of the support rim. This undercut allows a larger diameter for the support edge in the region of the transition from journal to support edge, wherein the support edge then tapers with increasing distance from the transition again. This can be created in a very stiff support edge.

Preferably, the support rim is formed dome-shaped. A dome has a very high rigidity, so that the dome-shaped support edge clamps the bearing pin very stiff.

It is furthermore advantageous if the cavity of the bearing journal has an opening towards the rear side of the lining part. Then, the bearing pin with a slider or by gas injection from the rear - seen from the cowling - inside are formed hollow and the bearing pin can thus front - seen to the vehicle interior - closed executed.

Furthermore, individual support ribs may be arranged on the outer circumference on the support edge in order to be able to introduce the bearing forces even better into the trim part. These support ribs can be arbitrarily shaped, it is important that the bearing forces are introduced over a large area on the back of the trim part in the trim part.

As a method for producing the corresponding trim part is the injection molding in question and there in particular the so-called internal pressure injection molding. The internal pressure injection molding is a special injection molding process for the production of hollow workpieces, which has been found to be particularly suitable for locally producing the hollow journal.

The difference to normal injection molding consists in a special work towards the end of the tool filling phase or after a defined partial filling of the mold. In the process-specific step, a fluid filler (usually water or inert gas) is injected into a partially filled mold so that it acts as an inner mold (die). By displacing the melt from the center grows on the one hand a cavity and on the other hand, the melt is pressed to or in the outer mold, so that the hollow bearing pin including the support edge and the opening arise.

It has been recognized that this method, which is particularly suitable for rod-shaped parts with very large wall thicknesses, can also be used for cladding parts with a high visual surface quality and an integral journal.

Thus, the former two-part product with different wall thickness can be produced in the area of the hollow trunnion without sink marks in a single operation. It has been recognized that the usual disadvantage of this method, namely that a hole occurs at the injection site, with a corresponding design of the nozzle and thus small diameter is not disturbing to the stability of the journal.

Because this disadvantage is compensated by the support edge. In particular, when the cavity of the trunnion is open to the back of the trim piece and the support edge is circumferentially disposed around the aperture, this is the case since flexing of the material or kinking etc. is effectively prevented.

In addition, it is desired that the cavity is formed substantially cylindrical, wherein in the region of the opening, a circumferential inner undercut is formed. This requires increased stability while saving material.

For the production, the fluid can be introduced by means of a nozzle, the opening of which is arranged at the tip of a conically tapered tube, wherein the angle of the conical surfaces is chosen such that the undercut is formed by inflowing fluid in the curing phase.

Preferably, a separate slide is provided in the mold for the journal. This is helpful if the Entformungsrichtung of the trim panel deviates from the Entformungsrichtung of the journal. Then first the slide for the bearing pin is moved back, and then removed from the cowling first. Thus, a stable bearing pin can be created regardless of the Entformungsrichtung of the tool.

Further details emerge from the following description of an embodiment of the invention with reference to the drawing. Show it:

1 a schematic perspective view of the visible side of a trim piece with integral bearing pin;

2 a schematic perspective view of the back of the trim panel ans 1 ; and

3 schematically a sectional view of a part of the manufacturing process of a trim piece with integral bearing pin according to the invention.

In the figures one is as a whole with 1 designated fairing shown. It has a visible surface 2 , which thus shows visible to the vehicle interior or is arranged in the installed state, and a back 3 , which is not visible accordingly.

The fairing part 1 consists of a plastic injection-molded body and comprises in one-piece construction one of the visible surface 2 the cowling protruding hollow approximately cylindrical bearing pin 4 for the storage of swiveling accessories.

The trim part further comprises a circumferential dome-shaped support edge 5 in the area of the transition between the hollow journal 4 and the remaining trim part 1 , where the support edge 5 on the invisible back 3 of the trim part 1 is arranged.

The cavity 7 of the journal 4 is to the back 3 of the trim part 1 open and the support edge 5 is circumferential around the opening 6 arranged.

The cavity 7 is substantially cylindrically shaped, being in the region of the opening 6 a circumferential inner undercut 8th is trained.

For the production of the trim part 1 can do that on average 3 shown tool 9 be used as part of a gas assist plastic injection molding process.

The tool 9 includes not only the usual components but also a device 10 for targeted gas supply. The device 10 includes a nozzle 11 at the top of a tapered pipe 12 , The angle of the conical surfaces 13 is chosen so that not only the cavity 7 but also the undercut 8th is formed by inflowing gas in the curing phase.

• a) in den Hohlraum der Spritzgußform 9 wird eine vorbestimmte Menge einer Kunststoffschmelze eingespritzt,
• b) in die Schmelze wird ein Gas mit einem solchen Druck derart über die Düse 11 eingebracht, dass sich die Schmelze unter Bildung des Lagerzapfenhohlraums 7 und der wulstartigen Stützrand 5 sowie der Hinterschnitt 8 gleichmäßig über die Oberfläche des Formhohlraums verteilt,
• c) nach einer Abkühlzeit wird zuerst der Schieber 14 für den Lagerzapfen nach hinten gefahren und dann die Form 9 geöffnet und das fertig gespritzte Verkleidungsteil der Form entnommen.

For making the trim part 1 with the journal 4 , the cavity 7 and the dome-shaped support edge 5 will go through the following steps:

• a) in the cavity of the injection mold 9 a predetermined amount of a plastic melt is injected,
• b) into the melt, a gas with such a pressure over the nozzle 11 introduced, that the melt to form the journal cavity 7 and the bead-like support edge 5 as well as the undercut 8th evenly distributed over the surface of the mold cavity,
• c) after a cooling time, the slider is first 14 for the journal driven back and then the shape 9 opened and removed the finished molded part of the mold.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 4204627 C2 [0006]
• EP 0289230 A2 [0009]
• DE 19827706 C2 [0010]

Claims (10)

Covering part in a vehicle interior made of plastic in one-piece construction with one of the visible surface ( 2 ) of the trim part ( 1 ) projecting hollow bearing journal ( 4 ) for the mounting of swiveling accessories, characterized in that the lining part ( 1 ) consists of a plastic injection-molded body in one-piece construction and a circumferential support edge ( 5 ) in the region of the transition between the hollow journal ( 4 ) and the remaining trim part ( 1 ), wherein the support edge ( 5 ) on the invisible back side ( 3 ) of the trim part ( 1 ) is arranged. Covering part according to claim 1, characterized in that the cavity ( 4 ) is formed substantially cylindrical. Covering part according to claim 1 or 2, characterized in that in the region of the support edge ( 5 ) a circumferential inner undercut ( 8th ) is trained. Covering part according to one of the preceding claims, characterized in that the supporting edge ( 5 ) is formed dome-shaped. Covering part according to one of the preceding claims, characterized in that the cavity ( 7 ) of the journal ( 4 ) to the back ( 3 ) of the trim part ( 1 ) an opening ( 6 ) having. Covering part according to one of the preceding claims, characterized in that between supporting edge ( 5 ) and the back ( 3 ) of the trim part ( 1 ) is formed at least one support rib. Method for producing a trim part according to one of the preceding claims, comprising the following steps: a) into a mold cavity of a closed injection mold ( 9 ) is injected with a predetermined amount of a plastic melt; b) a fluid is introduced into the melt at a pressure such that the melt melts to form the bearing journal cavity (US Pat. 7 ) evenly distributed over the surface of the mold cavity; and c) after a cooling time, the shape ( 9 ) and the hollow shaped body removed from the mold. A method according to claim 7, characterized in that the fluid is introduced in step b) and the shape is designed so that the support edge ( 5 ) and if necessary the undercut ( 8th ) is formed. A method according to claim 7 or 8, characterized in that the fluid is introduced by means of a nozzle whose opening at the tip of a tapered tube ( 12 ) is arranged, wherein the angle of the conical surfaces is selected so that the undercut ( 8th ) is formed by inflowing fluid in the Aushärtphase. Method according to one of claims 7 to 9, characterized in that for the bearing journal ( 4 ) a separate slider ( 14 ) in the shape ( 9 ) is provided.

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