Method for identifying a fiber-reinforced plastic component, and a resin transfer molding (RTM) mold

Abstract

A method for identifying a fiber-reinforced plastic component includes the acts of providing a fiber preform, applying a label to the fiber preform and holding it in place, inserting the preform together with the label in a mold and closing the mold, and infiltrating the preform with a plastic compound and curing it in the closed mold. In order to reliably identify the plastic component, the label comes to rest on a flow aid portion formed on the inner mold wall which has at least one channel-shaped depression. The longitudinal extension of the flow aid portion projects beyond the label.

Claims

1. A method for identifying a fiber-reinforced plastic component, comprising the acts of: providing a semifinished fiber product; applying a label to the semifinished fiber product; adhesively bonding the label to a surface of the semifinished fiber product; inserting the semifinished fiber product with the adhesively bonded label into a mold and closing the mold; and infiltrating the semifinished fiber product with a plastic compound and curing the plastic compound in the closed mold to form the fiber-reinforced plastic component; wherein a flow aid portion is formed on a portion of an inner wall of the mold with a lattice-shaped arrangement of channel-shaped depressions of which at least one channel-shaped depression has a length which projects beyond the label and wherein the label lies on the portion of the inner wall of the mold with the flow aid portion; wherein during the curing, a resin lattice is formed by the lattice-shaped arrangement which spans the label and which securely integrates the adhesively bonded label into the fiber-reinforced plastic component; wherein the lattice-shaped arrangement covers less than 30 percent of an area of the label or less than 20 percent of the area of the label.

2. The method according to claim 1, wherein a width of the at least one channel-shaped depression lies in a range from 0.2 mm to 5 mm.

3. The method according to claim 1, wherein the lattice-shaped arrangement has a peripheral annular channel.

4. The method according to claim 1, wherein the label is a nonsaturable carrier material.

5. The method according to claim 1, wherein the label has a QR code, a barcode or another machine-readable code.

6. A method for identifying a fiber-reinforced plastic component, comprising the acts of: providing a semifinished fiber product; applying and fixing a label to the semifinished fiber product; inserting the semifinished fiber product with label into a mold and closing the mold; and infiltrating the semifinished fiber product with a plastic compound and curing the plastic compound in the closed mold to form the fiber-reinforced plastic component; wherein the label lies on a flow aid portion which is formed on an inner wall of the mold with a lattice-shaped arrangement of channel-shaped depressions of which at least one channel-shaped depression has a length which projects beyond the label; wherein during the curing, a resin lattice is formed by the lattice-shaped arrangement which spans the label and which securely integrates the label into the fiber-reinforced plastic component; wherein the lattice-shaped arrangement covers less than 30 percent of an area of the label or less than 20 percent of the area of the label.

7. The method according to claim 6, wherein a width of the at least one channel-shaped depression lies in a range from 0.2 mm to 5 mm.

8. The method according to claim 6, wherein the lattice-shaped arrangement has a peripheral annular channel.

9. The method according to claim 6, wherein the label is a nonsaturable carrier material.

10. The method according to claim 6, wherein the label has a QR code, a barcode or another machine-readable code.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows the key method steps of a method according to the invention in a schematic view;

(2) FIG. 2 shows a detail view of the flow aid portion of the RTM mold from FIG. 1 in a plan view;

(3) FIG. 3 shows a sectional view of the flow aid portion from FIG. 2;

(4) FIG. 4 shows a plan view of a label integrated into the fiber-reinforced component; and

(5) FIG. 5 shows a sectional view of the component from FIG. 4.

DETAILED DESCRIPTION OF THE DRAWINGS

(6) In the method, a semifinished fiber product 1 in the form of a prepreg is first of all provided. A label 2 is applied to the semifinished fiber product 1 and fixed there. For example, the label 2 is a sticker which is printed with a QR code and which is adhesively bonded to the surface of the semifinished fiber product 1.

(7) The semifinished fiber product provided with the sticker is inserted into an RTM mold 3 whose cavity represents the outer contour of the fiber-reinforced plastic component to be produced. The cavity of the mold is delimited by the inner wall 4 and 5 of the mold parts 6 and 7.

(8) The mold wall 5 is formed as a flow aid portion 8 in the region in which the label 2 comes into contact with the mold 3, for which purpose the wall has at least one channel-shaped depression which is designed to be of such length as to project beyond the label.

(9) FIG. 2 shows a detail view of an exemplary flow aid portion 8 in a plan view. A plurality of channel-shaped depressions 10 to 24 are formed in the mold wall 5. The depressions 10 to 23 are arranged as straight lines which intersect one another in a cross-shaped manner and form a lattice-shaped arrangement 25. The channel-shaped depressions 10 to 23 are connected peripherally by an annular channel 24.

(10) The mold wall is set back in the region of the channel-shaped depressions; see the sectional view A-A of FIG. 3. If, then, a label is inserted into the RTM mold 3 and pressed against the flow aid portion 8, a hollow space between label 2 and mold wall 5 remains in the region of the channel-shaped depressions.

(11) To produce the fiber-reinforced plastic component, a curable plastic compound, for example an epoxy resin to which a curing agent is added, is injected into the closed mold 3 by means of a filling system 9 under a pressure of up to 80 bar. The plastic compound saturates the semifinished fiber product there and fills the channel-shaped depressions in the flow aid portion.

(12) The plastic matrix is cured and the fiber-reinforced plastic component 30 is produced by heating the RTM mold 3, for which purpose a correspondingly temperature-controlled liquid is channeled through heating tubes 26. In the region of the flow aid portion 8 there arise resin webs in the channel-shaped depressions 10 to 24 filled with plastic compound, the resin webs spanning the label 2 and securely fixing it to the component 30 and integrating it into the latter. The width and depth of the channel-shaped depressions 10 to 24 is preferably chosen such that, on the one hand, sufficient stability of the resin webs and, on the other hand, good readability of the label is ensured. It is advantageous in this respect if the width B of the channel-shaped depressions lies in the range from 1 to 5 mm. After curing, the component 30 can be demolded, with the label 2 being reliably released from the mold 3.

(13) FIG. 4 shows by way of example a plan view of the fiber-reinforced component 30 with integrated label 2. The label 2 is spanned by a lattice-shaped resin structure 31, the resin structure 31 being a positive reproduction of the channel-shaped depressions 10 to 24 of FIG. 2.

(14) FIG. 5 shows a sectional view B-B of the fiber-reinforced component 30 produced by the method. The semifinished fiber product 1 incorporated into the plastic matrix is present in the main body 32. The label 2 is arranged on the surface of the main body 32 and is spanned by the resin structure 31.

(15) The width of the channel-shaped depressions and their distance from one another in the lattice-shaped arrangement 25 are preferably chosen such that the resulting resin structure 31 covers less than 30 percent and preferably less than 20 percent of the area of the label 2. In order to allow higher tolerances in the positioning of the label, the lattice-shaped arrangement 25 preferably extends over an area which is at least double the area of the label.

(16) The channel-shaped depressions are not limited to a certain cross-sectional shape. It is also equally possible for the channel-shaped depressions to have a curved profile instead of the rectilinear profile shown. Nor does the flow aid portion have to be formed in the lower mold, but it can also be formed in the upper mold.

(17) The exemplary embodiments are not true to scale and are nonlimiting. Modifications within the practice of a person skilled in the art are possible.

LIST OF REFERENCE CHARACTERS

(18) 1 Semifinished fiber product 2 Label 3 RTM mold 4,5 Inner wall of the mold 6,7 Mold parts 8 Flow aid portion 9 Filling system 10 to 24 Channel-shaped depressions 25 Lattice-shaped arrangement 26 Heating tubes 30 Fiber-reinforced plastic component 31 Resin structure 32 Main body B Width of channel-shaped depression

(19) The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.