INJECTION MOLDING TOOL AND METHOD FOR PRODUCING MOLDED PARTS
20230092542 · 2023-03-23
Assignee
Inventors
- Richard LEBER (Weilheim-Noeggenschwiel, DE)
- Alex HAGENBUCH (Berikon, CH)
- Martin SCHOENAUER (Stetten, CH)
- Roman HUERLIMANN (Zufikon, CH)
Cpc classification
B29C45/14221
PERFORMING OPERATIONS; TRANSPORTING
B29C45/14196
PERFORMING OPERATIONS; TRANSPORTING
B29C2045/14188
PERFORMING OPERATIONS; TRANSPORTING
B29C43/183
PERFORMING OPERATIONS; TRANSPORTING
B29C43/40
PERFORMING OPERATIONS; TRANSPORTING
International classification
B29C45/14
PERFORMING OPERATIONS; TRANSPORTING
B29C43/18
PERFORMING OPERATIONS; TRANSPORTING
B29C43/36
PERFORMING OPERATIONS; TRANSPORTING
Abstract
A device for producing a composite molded part from planar and support structures includes a matrix, a punch, and a matrix slider, arranged to be movable relative to one another and in a closed state to define a cavity corresponding to the shape of the part to be produced. By and/or on at least one component, an edge folding arrangement is formed having a region fixing and/or pinching off and/or fully severing the decorative structure border. Also, a method for producing a composite molded part includes: providing a device, inserting a planar structure, transferring the device into a closed position and creating a cavity, introducing an uncured support structure, severing a strip of the structure protruding beyond the folded edge border, curing and demolding the composite molded part. Before and/or while introducing the uncured support structure, the planar structure is fixed in the folded edge outer border region.
Claims
1-17. (canceled)
18. A device for producing a composite molded part (1) having a planar structure (2), in particular a planar decorative structure, enveloping at least a part of the composite molded part, in particular a part of the surface of the composite molded part, and an at least partially injected support structure (3), comprising a matrix (4) for receiving the planar structure (2) in a non-composite state, a punch (5) and a matrix slider (6), wherein punch (5), matrix (4), and matrix slider (6) are arranged so as to be movable relative to one another, such that in a closed state, they define a cavity (A) together, which essentially corresponds to the shape of the composite molded part (1) to be produced, wherein an edge folding arrangement having a first curved region (12, 13) defining the folded edge and having a second region (8, 9, 10, 15, 17, 20, 21), spaced at a distance from the first, which fixes and/or pinches off and/or completely severs the edge-folded border of the planar structure (2), is formed by at least one region and/or on at least one region of one of the components matrix slider (6), punch (5) and/or matrix (4), wherein the punch (5) has an element for fixing the planar structure that is movable in a direction parallel to the matrix slider (6) in the region of its side wall, which region is facing the matrix slider (6).
19. The device according to claim 18, wherein in the second region (8, 9, 10, 15, 17, 20, 21), at least one of the components matrix slider (6), punch (5), or matrix (4), preferably the matrix slider (6), has a cutting edge (10), which in the closed state bridges a distance between an opposite component to at least 80%, preferably at least 90%, particularly preferably at least 95% until almost contacting the opposite surface.
20. The device according to claim 18, wherein the matrix (4) and the slider (6), in the closed state, together form the first region (12, 13) of the cavity (A) defining the folded edge, and the cutting edge (10) is formed on a, preferably protruding, border (9) of the slider (6) facing the punch (5).
21. The device according to claim 18, wherein the element movable in a parallel direction to the matrix slider (6) is an advancing tool (8), wherein the matrix slider (6) and the advancing tool (8) are movable independently of one another.
22. The device according to claim 19, wherein the matrix (4) has at least one suction opening (14) leading out of the cavity (A), which suction opening (14) can be connected to a device for air extraction.
23. The device according to claim 19, wherein the punch (5) has at least one compressed air feed (16) leading into the cavity (A) and connectable to a compressed air source.
24. The device according to claim 22, wherein a seal (17) is installed on the side wall of the punch (5), directly adjoining the contact point with the matrix slider (6) on the outside of the cavity (A).
25. The device according to claim 19, wherein in the region of its side wall facing the matrix slider (6), the punch (5) has an element (19) that is movable in a direction parallel to the matrix (4), which element (19) has an edge (20) or an arrangement of parallel fingers projecting into the edge folding region (12, 13), which are possibly extendable in the direction of the curved region (12, 13).
26. The device according to claim 19, wherein a heating arrangement (22) for the planar structure (2) is provided, possibly on at least one of the components matrix (4), matrix slider (6) and/or punch (5).
27. A method for producing a composite molded part (1) with a planar structure (2), preferably a decorative structure, enveloping at least a part of the surface of the composite molded part, and an at least partially injected support structure (3), comprising the steps of: a) providing a device with at least a punch (5), a matrix (4), and a matrix slider (6) in an open position; b1) inserting a not yet composite planar structure (2) into the device, such that the planar structure corresponds to at least a part of a contour of the composite molded part (1) to be obtained; b2) optionally using a planar structure (2) partially preformed with a folded edge; c) transferring the device into a closed position and creating a cavity (A) essentially determining the shape of the composite molded part (1) to be produced inside the device; d) inserting an uncured support structure (3) into the cavity; e) removing a strip (11) of the planar structure (2) protruding beyond the border of the folded outer edge on the rear side of the composite molded part (1); f) curing and subsequently g) demolding the composite molded part (1), wherein steps d) to f) may be performed in a different order and/or to some extent simultaneously; wherein during step c) of transferring the device in a closed position and during the creation of the cavity (A) inside the device essentially determining the shape of the composite molded part (1) to be produced, the outer border of the folded edge (2a) is fixed between two components moved in parallel with one another and is carried along with their closing movement, and prior to and/or while introducing the uncured support structure (3) in step d), the planar structure (2) is fixed in the region of the outer border of the folded edge (2a).
28. The method according to claim 27, wherein, the planar decorative structure (2) is fully edge-folded prior to or during the introduction of the uncured support structure in step d) and in any case prior to the removal of the strip (11) of the planar decorative Structure (2) protruding beyond the outer border of the folded edge (2a) on the rear side of the composite molded part (1) in step e).
29. The method according to claim 27, wherein the planar structure (2), in particular the border region having the folded edge (2a), is sucked onto and/or into the matrix (4) and/or the curved region (12, 13) between matrix (4) and matrix slider (6) by applying a vacuum.
30. The method according to claim 27, wherein the planar structure (2), in particular the border region having the folded edge (2a), is pressed onto and/or into the matrix (4) and/or the curved region between matrix (4) and matrix slider (6) by applying an excess pressure.
31. The method according to claim 29, wherein the distance between the components is sealed at least during the application of the vacuum and/or the excess pressure.
32. The method according to claim 27, wherein the planar structure (2) is pressed into the curved region of matrix (4) and/or matrix slider (6) by means of at least one mechanical element (20).
33. The method according to claim 27, wherein the planar structure (2) is heated prior to and/or at least during the edge folding process.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0046] For the purpose of better understanding of the invention, it will be elucidated in more detail by means of the figures below.
[0047] These show in a respectively very simplified schematic representation:
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DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0076] First of all, it is to be noted that in the different embodiments described, equal parts are provided with equal reference numbers and/or equal component designations, where the disclosures contained in the entire description may be analogously transferred to equal parts with equal reference numbers and/or equal component designations. Moreover, the specifications of location, such as at the top, at the bottom, at the side, chosen in the description refer to the directly described and depicted figure and in case of a change of position, these specifications of location are to be analogously transferred to the new position.
[0077] The exemplary embodiments show possible embodiment variants, and it should be noted in this respect that the invention is not restricted to these particular illustrated embodiment variants of it, but that rather also various combinations of the individual embodiment variants are possible and that this possibility of variation owing to the technical teaching provided by the present invention lies within the ability of the person skilled in the art in this technical field.
[0078] Finally, as a matter of form, it should be noted that for ease of understanding of the structure, elements are partially not depicted to scale and/or are enlarged and/or are reduced in size.
[0079] The invention is used particularly in the production of back-injected composite molded parts 1, in which a planar structure 2, in particular a planar decorative structure such as, for example, a decorative film or a decorative fabric, envelops at least a part of the surface of the composite molded part 1. The structure 2 is back-injected with an initially liquid and subsequently curing support structure 3. The planar structure 2 has a folded edge 2a on the border of the molded part 1, which folded edge 2a may extend up to the border of the composite molded part 1, but also around the border, even all the way to the rear side not covered by a planar structure 2. Particularly preferably, such composite molded parts are used as trim components in the passenger compartment of vehicles.
[0080] The device for producing such composite molded parts, schematically shown in a first embodiment in
[0081] This first embodiment of a device according to the invention further has an advancing tool 8, which is arranged on a side wall of the punch 5 facing the matrix slider 6, preferably at least partially receivable in a recess of the punch 5. The matrix slider 6, in turn, has a protrusion 9 protruding towards the punch 5, preferably in the region of the upper border of the advancing tool 8.
[0082] On the outermost border of the protrusion 9 of the matrix slider 6, a cutting edge 10 is formed, which, in the closed state of the mold elements 4, 5, 6, 8, bridges the distance between the protrusion 9 of the matrix slider 6 and the punch 5, here preferably the advancing tool 8, to at least 80%. The cutting edge 10 may also be formed such that it bridges at least 90%, particularly preferably at least 95%, of the distance for an easy detachment of the protruding border strip 11 of the decorative structure 2, which detachment involves little stress on the surrounding region of the composite molded part. In the closed state of the device, the cutting edge 10 may also fully rest against the opposite component and thus sever the material of the planar structure 2 completely.
[0083] Instead of a continuous cutting edge 10, other designs are also possible, for example a series of individual pins or needles for achieving a perforation of the material of the planar structure 2 where its border strip 11 can be removed.
[0084] The matrix slider 6 and the advancing tool 8 are movable via their drives, in a parallel direction independently of one another, in particular movable towards one another such that a transition between the border strip 11 and the region of the planar structure 2 meant to remain on the composite molded part 1 can be gripped between these two components 6, 8 movable in parallel with one another, fixed, and edge-folded in a targeted manner and to any desired degree while the molding tool is closing.
[0085] A curved section 12 is formed on the matrix 4, and on the matrix slider 6, a curved section 13 is formed as well, which sections 12, 13 are directly opposite one another and form a first region defining the folded edge 2a of the planar structure 2 when the device is closed. The cutting edge 10 of the matrix slider 6 and the surface of the advancing tool 8 opposite the cutting edge 10 are spaced apart from the sections 12, 13 by the desired width of the folded edge 2a on the rear side of the composite molded part 1 and forms a second region, in which the region initially fixing and subsequently pinching off and/or fully severing the edge-folded border of the decorative structure 2 is formed.
[0086] For producing a composite molded part 1 as initially characterized, the device is brought into the opened position shown in
[0087] Subsequently, the device is transferred into a closed position in order to thus finally form a cavity A essentially determining the shape of the composite molded part 1 between the mold elements 4, 5, 6, 8.
[0088] An intermediate position in this course of movement is shown in
[0089] In further consequence, the matrix slider 6 is moved further towards the punch 5 and thus, the protrusion 9 of the matrix slider 6, in particular its cutting edge 10, finally comes into contact—or, as explained above, almost into contact—with the extended advancing tool 8. This causes that the material of the planar structure 2 is gripped and/or clamped between the protrusion 9 and the advancing tool 8 (see
[0090] At the latest when the completely closed position of the mold elements 4, 5, 6, 8, shown in
[0091] By fixing the clamped border of the planar structure 2 between the matrix slider 6 and advancing tool 8 and actively carrying it along when closing the mold elements 4, 5, 6, 8, here particularly when the matrix slider 6 and the advancing tool 8 retract together, the planar structure 2 is fixed in the region of the outer border of the folded edge 2a prior to or during the introduction of the uncured support structure 3, and in any case is completely edge-folded before the strip 11 of the planar decorative structure 2 protruding beyond the outer border of the folded edge 2a on the rear side of the composite molded part 1 is removed. Thus, folded edges of more than 90° with a precisely predefined geometry of the folded edge can be produced in a simple manner.
[0092] A further embodiment of a device according to the invention is illustrated in
[0093] For producing a composite molded part 1, the planar structure 2 is inserted into the opened device as shown in
[0094] Subsequently, the device is transferred into a closed position, during which the extraction of the air between the planar structure 2 and the matrix 4 through the suction opening 14 can already be started.
[0095] An intermediate position in this course of movement is shown in
[0096] In further consequence, the matrix slider 6 is further advanced towards the punch 5 and thereby, the protrusion 9 of the matrix slider 6 with its region directly outside the cutting edge 10—as viewed with respect to the cavity A—finally comes into contact with the seal 15 as is shown in
[0097] During and after the continuation of the closing operation of the mold elements 4, 5, 6 of the device, the material of the planar structure 2 is sucked into the curved region 12, 13 between the matrix 4 and the matrix slider 6 and clings with the outer edge to said mold elements 4, 6 on the front side of the composite molded part as well as on the folded edge 2a, wherein the border region directly adjoining the folded edge 2a remains fixed between the matrix slider 6 and the punch, in particular between the protrusion 9 of the matrix slider 6 and the seal 15 on the punch 5, and is formed in accordance with the movement of the matrix slider 6. This position is shown in
[0098] With respect to introducing the support structure that has not yet cured, curing, severing the border strip 11, and demolding the finished composite molded part 1, the explanations made regarding the first embodiment apply.
[0099] An exemplary position for the suction opening 14 is shown in
[0100] A further possibility for actively shaping the planar structure 2 in the device in the region of the folded edge 2a on the border of the composite molded part 1 is also to press its border region, by means of compressed air, against the arrangement of the curved sections 12, 13 provided for forming the folded edge 2a on the matrix 4 and the matrix slider 6. According to a further embodiment of the device according to the invention shown in
[0101] In order to emphasize the effect of the compressed air even more, a seal 17 may again be arranged on the side wall of the punch 5. With respect to the folded edge 2a and the contact region of the protrusion 9 of the matrix slider 6 with the punch 17, the seal 17 is arranged so as to directly adjoin and outside on the side wall of the punch 5.
[0102] Advantageously, a clamping arrangement 18 for the protruding border 11 of the planar structure 2 is provided on the outer side between the matrix slider 6 and the punch 5.
[0103] After inserting the planar structure 2 into the opened device of
[0104] The closing process of the mold elements 4, 5 and now also that of the matrix slider 6 is further continued, just like the injection of compressed air. Finally, after going through the positions of
[0105] The molding of the curved section of the folded edge 2a on the border of the planar structure 2 can hereby also be effected by a further embodiment of the device according to the invention. This device shown in an opened state in
[0106] At its upper border, which comes to rest in the region of the folded edge 2a of the planar structure, the punch slider 19 is provided with an edge 20 protruding into the edge folding region. Instead of a continuous edge 20 or cutting edge, discrete, distanced protrusions, similar to those of a rake or a comb with a plurality of tines, or similar arrangements with the same effect, or combinations of such different elements may be present. In any case, these elements are movable, preferably extendable into the edge folding region in parallel with the direction of movement of the matrix slider 6 or in another direction.
[0107] After inserting the planar structure 2 into the matrix 4 into the fully opened mold elements 4, 5, 6 (
[0108] During demolding, as shown in
[0109] A further embodiment provides for the active formation of the folded edge 2a by means of thermoforming of the planar structure. The device for this, again provided for the beginning of a cycle of the production process, is shown in
[0110] After inserting the planar structure 2, which is still cold,—as shown in
[0111] Advantageously, a clamping frame 23 is also introduced into the tool or is an integral part thereof, which clamping frame 23 presses the decorative film 2 against the seal 21. Even while the or each heating element 22 is activated, the matrix slider 6, on the seal 21 of which the planar structure 2 is supported with its border region, still remains closed. Due to the heat of the heating element 22, the material is eventually softened, which results in a clinging to the contour of the matrix 4, in particular also in the curved edge folding region of the sections 12, 13. All other types of defined production of the folded edge 2a by means of active fixing and carrying along the edge-folded border region while closing the mold elements—as explained by way of example in the previous paragraphs in the context of the other exemplary embodiments of the invention—can be supported by softening the planar structure 2. Generally, all mentioned method variants may also be used in any combination, wherein the devices may be equipped with combinations of the described edge folding arrangements.
[0112] By way of example,
[0113] Lastly, the mold elements 4, 5, 6 are closed, wherein the matrix slider 6 can possibly be opened slightly once more, and the device is brought into the position of
[0114] Due to the fixation of the border region of the planar structure on at least one of the mold elements 4, 5, 8 or between two mold elements 6, 8, which is provided in all embodiments according to the invention, precisely defined folded edges, even of more than 90° can be obtained reliably and reproducibly in that the border of the structure 2 in the injection molding tool is folded into the edgefold geometry in a targeted manner. This is preferably defined by the curved sections 12, 13 on the mold elements, in particular the matrix 4 and the matrix slider 6. After back-injection molding and demolding, the composite molded part 1 is fully edge-folded and trimmed.
LIST OF REFERENCE NUMBERS
[0115] 1 Composite molded part [0116] 2 Planar structure [0117] 2a Folded edge [0118] 3 Support structure [0119] 4 Matrix [0120] 5 Punch [0121] 6 Matrix slider [0122] 7 Drive [0123] 8 Advancing tool [0124] 9 Protrusion matrix slider [0125] 10 Cutting edge matrix slider [0126] 11 Border strip [0127] 12 Curved section matrix [0128] 13 Curved section matrix slider [0129] 14 Suction opening matrix [0130] 15 Seal punch [0131] 16 Compressed air feed [0132] 17 Seal punch [0133] 18 Clamping arrangement [0134] 19 Punch slider [0135] 20 Edge punch slider [0136] 21 Seal matrix slider [0137] 22 External heating element [0138] 23 Clamping element [0139] A Mold cavity