DE102014011135B4 - Method and device for producing a decorative part - Google Patents

Abstract

Method for producing a decorative part (32) in a turning tool (2, 4, 6) comprising a turning plate (2) and two translationally movable tool elements (4, 6) which can be applied to the turning plate (2) and which have two surfaces (14, 26) of the insert (2) each form a cavity (20, 28), wherein in the method a decorative layer (16) for producing a reinforced decorative layer (16, 22) in one between the insert (2) and the one Tooling (6) formed cavity (20) is provided on the back with a reinforcing layer (22) and after turning the insert (2) formed in a between the insert (2) and the other tool element (4) cavity (28) on one of Reinforcing layer (22) opposite the visible side a cover layer (24) on the decorative layer (16) is applied, characterized in that when turning the insert (2) the reinforced decorative layer (16, 22) on a reinforcing layer (22) forming tool element (6 ) remains and after turning the insert (2) on a visible side of the decorative layer (16), the cover layer (24) forming cavity (28) between this reinforcing layer of the forming tool element (6) and the insert (2) is formed.

Description

The present invention relates to a method and an apparatus for producing a decorative part. The present invention further relates to an improved device for producing a component made of a different plastic layers produced in a turning tool.

The present invention relates generally to the manufacture of decorative parts. Such decorative parts are usually produced in a turning tool by means of injection molding. This injection mold has two usually translationally movable tool elements, between which a turning plate is provided, which is rotatably movable to provide the respective tool elements associated mating surfaces. By translationally closing the tool elements, a cavity is formed in each case between the two tool elements and the insert. Usually, a first cavity is formed in this way to form a first, usually a reinforcing layer of the decorative part forming layer on the back of the decorative layer. This reinforced decorative layer is then rotated with the turning tool, so that formed between the decorative layer and the other tool element between the decorative layer and the mold cavity formed by the further mold surface a cover layer and the decorative layer can be provided with a usually transparent coating. Such a method is known for example from JP H03- 30 922 A.

The respective mold cavity surfaces of the tool elements are connected via hot runners with plasticizing. When producing the back reinforcing layer, in practice the decorative layer bears against the associated tool element. The plastic melt must accordingly be guided past the side and outside the contour of the finished decorative part in order to bring the plastic component forming the reinforcing layer onto the rear side of the decorative layer opposite the corresponding plasticizing aggregate. Especially with large-scale decorative parts, this leads to problems in the formation of the reinforcing layer. The reinforcing layer is relatively thin-walled. This results in long flow paths. In order to prevent the plastic melt from freezing prematurely in the mold cavity, relatively high injection pressures and velocities must be used. For example, if the decorative layer is a veneer part, such conditions are sometimes detrimental to the decorative part. It can lead to mechanical or thermal damage to the decorative layer. These problems increase with very large decorative parts. It is true that the plastic forming the reinforcing layer can be introduced relatively broadly into the cavity through an adapted configuration of the cavity. However, such a configuration has other disadvantages, such as increased tooling costs and in particular excessive consumption of thermoplastic, which is discarded to a considerable extent in the context of the production of the product by marginal trimming.

The present invention is based on the problem to provide an improved method for producing a decorative part and a device suitable for this purpose. The present invention also seeks to provide an improved apparatus for processing a plurality of plastic components.

The WO 2011/083002 A1 discloses a floor-turning tool which is also used to practice the teachings of the present invention and which includes two translationally-movable tooling elements and an insert plate therebetween. In this case, a central body is formed in a cavity which is formed between the insert and the one of the tool elements. Thereafter, the insert is turned by pivoting 180 °. The base body is held by the insert, with-pivoted and arranged opposite to cavities, which are provided on the other translationally movable tool element. This translatory-moving tool element is closed in order to form a cavity for one-sided encapsulation of the central body. The one-sided encapsulation is denoted by reference numerals in FIG 5d characterized.

Thereafter, this translatorsich-movable tool element is turned on its own about an axis which extends parallel to that axis to which this tool element is translationally movable. Thus, the insert, the lead here fixed, and the tool element form a conventional turning tool. When turning the tool element, the one-sided overmolded base body remains on the tool element. The mold surfaces forming the opposite second extrusion are formed by a mold cavity portion of the insert.

Thereafter, the insert is turned by 90 ° in order to demold the twice-molded components. The insert according to WO 2011/083 002 A1 is then only required to produce the base body. The double-sided encapsulation of the base body is effected by turning the translationally movable tool element, whereas the other, the cavities each completing tool, namely the insert, remains stationary. The main body changes the parting line. He is first held on the side of the insert and is after the one-sided encapsulation and opening the translationally movable tool element transferred to this. After the second encapsulation, the finished product remains on the insert and is finally removed from the mold.

The WO 2014/025138 A1 discloses wrapping a reinforcing bar in a turning tool. One half of the turning tool serves to first produce the reinforcement bar. This consists of a hardenable plastic, which is cured with heat to give the reinforcing member the necessary strength. Thus, the shaping and curing of the reinforcement bar between the turning tool and a translationally movable tool element.

Thereafter, the turning tool is turned to provide the cured reinforcing bar opposite to another translationally movable tool element. Between this and the turning tool, a cavity is formed in the first plastic is introduced. During injection molding, the translationally movable tool element is moved away to form a cavity on the opposite side of the cured reinforcing bar and to introduce plastic into it. The first and the second cavity are each formed between the other tool element and the turning tool.

To solve the procedural aspect, the present invention provides a method having the features of claim 1. In this method, the decorative layer is first provided in a conventional manner with a reinforcing layer. In this case, usually thermoplastic is processed to produce the reinforcing layer, d. H. injected in a molten state via a plasticizing unit of an injection molding machine. The process control according to the invention uses a turning tool in a manner known per se. As a turning tool in the context of the present invention, a tool with at least one tool element and a turning plate with at least two surfaces to be considered, which each form a cavity together with a mating surface of the usually translationally movable and can be applied to the insert tool element. The following description of the invention is based on the basic shape of a turning tool, in which the corresponding surfaces are usually provided diametrically opposite to the insert, so that on opposite sides tool elements can be provided, which can be applied to form two cavities of the insert. It goes without saying that in the case of only one tool element, the at least two surfaces of the insert can be arranged at arbitrary positions thereof, i. not necessarily opposite must be arranged. It goes without saying that the present invention is also executable with a turning plate with four each offset by 90 ° relative to the pivot axis of the insert arranged surfaces and four correspondingly associated tool elements. This embodiment should also be encompassed by the present invention. Such a configuration is usually used to form the cover layer in a first position, the reinforcing layer and in a position offset by 90 ° to the insert. In the following, however, the basic form with only two surfaces of the insert will be discussed. As far as in this context on opposing components of the device is turned off, this is not to be understood as limiting. In the case of a turning tool with four surfaces "opposite" can also be understood, for example, in the sense of "offset 90 °".

In the case of the process control according to the invention, however, the reinforced decorative layer provided with the reinforcing layer remains on that usually not rotatable or pivotable tool element on which the reinforcing layer was previously formed. The turning of the turning tool thus does not lead to a local displacement of the reinforced decorative layer as an intermediate product when turning the insert. Rather, by turning the insert opposite to the reinforcing layer forming tool element, another surface of the insert is provided which forms between the visible side of the decorative layer and the insert a cavity, which is provided for forming the cover layer. The remaining on the tool element reinforced decorative layer accordingly forms after closing the injection mold, d. H. Applying the usually translationally movable tool element to the insert between its visible side and one of the outer contour of the cover layer corresponding mold cavity surface of the insert from the cover layer forming cavity.

With this procedure, it is possible first to transfer the back of the decorative layer directly to the rear injection without the plasticized plastic first on the decorative layer and on the insert. Rather, the back of the decorative layer takes place in a cavity which is formed between the back of the supported by the insert decorative layer and the tool element. Long flow paths can be avoided. Since the reinforcement layer on the finished product is covered by the decorative layer, any desired injection points can be selected in order to make the best possible the thermoplastic forming the reinforcement layer to introduce into the cavity forming the reinforcing layer and mold it.

The already stabilized intermediate product can then be provided with the cover layer. In this case, the decorative layer thus reinforced remains on the tool element which was used to produce the reinforcing layer. The material forming the cover layer on the visible side may optionally be introduced from the same side as the material forming the reinforcement layer. With a view to the most uniform possible spread of the melt on the visible side of the decorative part, however, it is preferable to bring the visible side forming material directly on the insert and not through channels that pass through the tool parting plane between the tool element and the insert. Such a metering unit for the material of the cover layer can for example be directly connected to the insert and pivotally provided with this. By way of example, the metering unit is a mixing head for mixing reactive components which, for example, form a PUR cover layer on the visible side of the decorative layer.

In order to increase the output, another decor layer is preferably provided with its reinforcing layer in the method according to the invention when forming the cover layer on one side of the insert opposite the cover layer. Thus, as is customary in two-component injection molding, increased output is also achieved in the method according to the invention by supplying material to the visible side or the back side of the decorative layer on opposite sides of the insert in order to form the reinforcing layer or cover layer ,

With a view to the independent aspect of the present invention, this proposes a tool for producing a decorative part with features of claim 3. The device has a turning plate, which cooperates in a manner known per se with at least one tool element, which is usually translationally movable on the turning plate. The peculiarity of the present invention, however, consists in that the insert has a contour corresponding to the contour of the decorative layer in the decorative part supporting surface, which forms a reinforcing layer forming cavity together with a Formnestoberfläche this can be applied to the insert tool element between the decorative layer and the Formnestoberfläche cavity, wherein the Turning plate further comprises a the outer contour of the cover layer corresponding mold cavity surface, which forms a cover forming the cavity together with the visible surface of a reinforced with the reinforcing layer decor layer between the decorative layer and the insert. It goes without saying that the cavities according to the present invention are formed only when the tool element is applied against the insert. The turning tool according to the invention is characterized accordingly by two surfaces, namely on the one hand a support surface for the decorative layer and on the other hand, a mold cavity surface for forming the cover layer. In contrast, in the conventional embodiment of the apparatus described above, the insert plate forms a mold cavity surface in a first station for forming a cavity forming the reinforcement layer. The support surface for the decorative layer is formed in the prior art by the translationally movable tool element. Since the reinforced decorative layer is turned with the insert, this forms no second, differently designed surface. Rather, the surfaces are identical in the prior art, whereas the opposite surfaces of the insert are formed differently according to the present invention, on the one hand to support the decorative layer and on the other hand to mold the cover layer.

As already mentioned above, it is preferable to provide the insert between at least two opposing translationally movable tool elements. The tool elements usually have identically shaped mold cavity surfaces, so that identical back reinforcing layers are respectively molded between the mold cavity surfaces and the mating surfaces of the insert.

Furthermore, it is preferable to equip the at least one usually translationally movable tool element with ejectors. While conventionally the ejector are provided on the insert to demold the finished decorative part after double-sided encapsulation of the decorative layer of the insert, the demolding of the decorative part of the device according to the invention is usually carried out from the translationally movable tool element. This demolding is facilitated by said ejector pins.

The translationally movable tool element is usually associated with an aggregate for plasticizing and injecting a thermoplastic plastic component. In contrast, it is proposed according to a preferred embodiment of the present invention to connect a metering unit for metering a covering layer forming material with the insert. This metering unit can be provided directly on the insert and can be pivoted or pivoted with it about the pivot axis.

Further details and advantages of the present invention will become apparent from the following description of an embodiment in conjunction with the drawings. In this show the 1A-I a sequence for producing an embodiment of a decorative part in a turning tool.

In the illustrated in the figures embodiment of the device according to the invention denotes reference numerals 2 a reversible plate which is pivotally mounted about an axis passing through the plane of the figures. The insert 2 can be moved 180 ° back and forth. It can also be rotated in the same direction. The insert 2 is between opposed tool elements 4 . 6 provided translational relative to the insert 2 movably arranged and in each case a Plastifzieraggregat 8th . 10 assigned. The insert 2 carries a dosing unit 12 comprising a mixing head not shown in detail for injecting reacting components of a polyurethane.

The following description of the method steps is carried out initially on the right side of the 1A-I ,

In the in 1A shown open position is right on the turning tool 2 and supported by a support surface formed by this 14 a decorative layer 16 , The decor layer 16 has one of the contouring of the support surface 14 corresponding embodiment and is flush with the support surface 14 at. After closing the turning tool by applying the two tool elements 4 . 6 to the insert 2 is between the decor layer 16 and one through the tool element 6 formed mold nest surface 18 a cavity 20 ( 1B) formed, the impression of a reinforcing layer 22 serves (cf. 1C ).

After molding the reinforcement layer 22 by injecting a thermoplastic over the plasticizing unit 10 becomes the turning tool 2 open. Both tool elements 4 . 6 with their associated plasticizing units 8th . 10 become translationally from the insert 2 moved away ( 1D ). This will be turned over afterwards ( 1E) , The remains with the reinforcing layer 22 provided reinforced decorative layer 16 in contact with the mold nest surface 18 of the tool element 6 , The insert 2 is accordingly turned without an associated intermediate product. As a result of turning, there is one covering layer 24 forming mold cavity surface 26 the insert 2 opposite to the visible surface of the decorative layer 16 (see. 1F) , By re-closing the turning tool is between the tool element 6 and the mold nest surface 26 of the tool element 6 one the top layer 24 molding cavity 28 formed (cf. 1G) , In these are about the dosing 12 reactive components of a curing polyurethane in the cavity 28 injected. The polyurethane cures in the cavity 28 and forms accordingly the transparent (clear or colored) cover layer 24 on the visible surface of the decorative layer 16 out.

The above description of the embodiment explained the embodiment of the apparatus and the method guide based on the right side of 1A-I , It should be noted that the tool elements 4 . 6 and the plasticizing units 8th . 10 usually match each other. For the production of two components in one cycle, the further tool element shown on the left in the figures is shown 4 intended. The between this tool element 4 and the support surface 14 the insert 2 provided cavity 20 is filled in the same way with thermoplastic by injection molding, as in 1B on the right side shown cavity 20 (see. 1H) ,

Of course, the cover layer 24 usually as a layer of uniform thickness on the decorative layer 16 intended. In the exemplary embodiment, another form has only been made for reasons of better representability of the different layers within the cavities 20 respectively. 28 and for better distinguishability of the positions of the insert 2 selected.

As can be seen, this becomes the reinforcing layer 22 forming material directly against the back of the decorative layer 16 molded, whereas that the top layer 24 forming material directly against the visible surface of the decorative layer 16 is formed. In particular - in contrast to the prior art practiced - the reinforcing layer 22 molding thermoplastic material not initially on a parting plane 30 (see. 1G) between the insert 2 and the associated tool element 4 . 6 enforce, then only against the back surface of the decorative layer 16 to be injected. The special feature of the present invention is, inter alia, that the metering unit 12 rotatable with the insert 2 arranged and attached directly to this.

In the 11 becomes right, in 1D left a decorative part 32 removed from the mold. The addition to the tool element 6 respectively. 4 associated ejector are not shown here.

LIST OF REFERENCE NUMBERS

2

insert

4

Tool element (left side)

6

Tool element (right side)

8th

Plasticizing unit (left side)

10

Plasticizing unit (right side)

12

metering unit

14

support surface

16

decorative sheet

18

Mold nest surface (right side)

20

Cavity for the impression of the reinforcement layer

22

reinforcing layer

24

topcoat

26

Cavity surface

28

Cavity for molding the cover layer

30

parting plane

32

decorative part

Claims (9)

Method for producing a decorative part (32) in a turning tool (2, 4, 6) comprising a turning plate (2) and two translationally movable tool elements (4, 6) which can be applied to the turning plate (2) and which have two surfaces (14, 26) of the insert (2) each form a cavity (20, 28), wherein in the method a decorative layer (16) for producing a reinforced decorative layer (16, 22) in one between the insert (2) and the one Tooling (6) formed cavity (20) is provided on the back with a reinforcing layer (22) and after turning the insert (2) formed in a between the insert (2) and the other tool element (4) cavity (28) on one of Reinforcing layer (22) opposite the visible side a cover layer (24) on the decorative layer (16) is applied, characterized in that when turning the insert (2) the reinforced decorative layer (16, 22) on a reinforcing layer (22) forming tool element ( 6) remains and, after turning the insert (2) on a visible side of the decorative layer (16), the cavity (28) forming the cover layer (24) is formed between said tool element (6) and said insert (2). Method according to Claim 1 , characterized in that when forming the cover layer (24) on one of the cover layer (24) forming cavity (28) opposite side another decorative layer (16) is provided with its reinforcing layer (22). Device for producing a decorative part (32) having a reinforcing layer (22) and a cover layer (24) and a decorative layer (16) interposed therebetween, having a tool element (4) which can be moved in a translatory manner and can be applied to the insert (2) , 6) comprehensive turning tool (2, 4, 6), characterized in that the insert (2) has a contour of the decorative layer (16) in the decorative part (32) corresponding support surface (14), which together with a mold cavity surface (18 ) of a tool element (6) between the decorative layer (16) and the mold cavity surface (18) forming a reinforcing layer (22) cavity (20) is formed, and one of the outer contour of the cover layer (24) corresponding mold cavity surface (26) which together with a visible surface of one with the reinforcing layer (22) reinforced and held on the other of the tool elements (4) decorative layer (16) between the decorative layer (16) and the turntable (2) forms a cavity (28) forming the cover layer, wherein the support surface (14) and the mold cavity surface (26) can be optionally turned by turning the insert (2) with the two tool elements (4, 6) ) or the reinforcing layer (22) forming cavity (20) form. Device after Claim 3 , characterized in that the turning plate (2) is provided between two oppositely each translationally movable tool elements (4, 6). Device after Claim 4 , characterized in that the two translationally movable tool elements (4, 6) identical Formnestoberflächen (18) for forming the reinforcing layer (22) form. Device according to one of Claims 3 to 5 , characterized in that the at least one tool element (4, 6) is equipped with ejectors. Device according to one of Claims 3 to 6 , characterized in that the at least one tool element (4, 6) is associated with an aggregate (8, 10) for plasticizing and injecting a thermoplastic plastic component. Device according to one of Claims 3 to 7 , characterized in that the insert is connected to a metering unit (12) for metering a material forming the cover layer (24). Device after Claim 8 , characterized in that the metering unit (12) is a component of a polyurethane injecting mixing head.

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