Method and system for reworking a composite laminate

Abstract

A method for reworking a composite laminate comprising a plurality of tapes, comprising the following steps: detecting the occurrence of a defect on a tape of composite material while the tape is being laid up; continuing the lay-up of the defective tape until a tape length is formed which surpasses a manufacturing length of the tape; catching the part of the defective tape that surpasses the manufacturing length of the tap; cutting the defective tape in the part of the defective tape that surpasses the manufacturing length of the tape; removing from the laminate the caught defective tape by the catching system, and laying-up a replacement tape in the place of the removed defective tape.

Claims

1. A method for reworking a composite laminate, the laminate comprising a plurality of tapes of composite that are being laid up by an automated tape placement machine comprising a laying head, comprising the following steps: detecting an occurrence of a defect on a tape of composite material while the tape is being laid up, continuing the lay-up of the defective tape until a tape length is formed which surpasses a manufacturing length of the tape, catching the part of the defective tape that surpasses the manufacturing length of the tape with a catching system, cutting the defective tape in the part of the defective tape that surpasses the manufacturing length of the tape, removing from the laminate the defective tape caught by the catching system, and after removal of the defective tape, laying-up a replacement tape in place of the removed defective tape by the automated tape placement machine.

2. The method for reworking a composite laminate, according to claim 1, wherein an automated inspection system is provided for detecting the occurrence of the defect.

3. The method for reworking a composite laminate, according to claim 1, wherein the catching system is deployed over the laminate after detecting the occurrence of the defect and retracted from the laminate after removal of the defective tape.

4. The method for reworking a composite laminate, according to claim 3, wherein before deployment of the catching system, the laying head is separated from the defective tape.

5. The method for reworking a composite laminate, according to claim 1, wherein the catching system comprises a clamp with two jaws which trap the defective tape in-between.

6. The method for reworking a composite laminate, according to claim 5, wherein the removal of the defective tape is done by rewinding the defective tape around the clamp.

7. The method for reworking a composite laminate, according to claim 1, wherein the defective tape is cut after being caught by the catching system.

8. A reworking system for a composite laminate comprising a plurality of tapes of composite configured for being laminated by an automated tape placement machine comprising a laying head, wherein the reworking system comprises: a catching system configured to catch a defective tape when an occurrence of a defect on the tape is detected during the laying of the tape, and the catching system comprising means for removing a caught defective tape from the laminate, further comprising a clamp with two jaws configured to trap the defective tape in-between, wherein the clamp comprises two external shells and two internal cores located in the external shells and in an opposite location, the internal cores being movable with respect to the external shells such that they trap the defective tape in-between when they approach each other and release the defective tape when they move away from each other.

9. The reworking system for a composite laminate, according to claim 8, wherein the clamp comprises means for rewinding the defective tape around the clamp.

10. The reworking system for a composite laminate, according to claim 8, wherein the defective tape is rewound around the external shells.

11. A reworking system for a composite laminate comprising a plurality of tapes of composite configured for being laminated by an automated tape placement machine comprising a laying head, wherein the reworking system comprises: a catching system configured to catch a defective tape when an occurrence of a defect on the tape is detected during the laying of the tape, and the catching system comprising means for removing a caught defective tape from the laminate, and further comprising: means for receiving a signal that a defect has occurred on a tape that is being laid-up, means for continuing the lay-up of the defective tape until a tape length is formed that surpasses a manufacturing length of the tape, means for sending a signal to the reworking system for catching the part of the defective tape that surpasses the manufacturing length of the tape and for removing the defective tape, means for cutting the defective tape in the part of the defective tape that surpasses the manufacturing length of the tape before being removed, and means for laying-up a replacement tape after removal of the defective tape.

12. The reworking system for a composite laminate, according to claim 11, further comprising a clamp with two jaws configured to trap the defective tape in-between.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) To complete the description and in order to provide for a better understanding of the invention, a set of drawings is provided. The drawings form an integral part of the description and illustrate preferred embodiments of the invention. The drawings comprise the following figures.

(2) FIG. 1 shows a schematic representation of an automated tape placement machine.

(3) FIG. 2 shows a schematic representation of the cutting process in an automated tape placement machine.

(4) FIG. 3 shows a schematic representation of a first step of the invention in which a defect on a tape that is being laid is detected.

(5) FIG. 4 shows a schematic representation of an additional step of the invention in which the laying-up process of the defective tape is continued until the end of a course.

(6) FIG. 5 shows a schematic representation of a next step of the invention in which the pressure roller is separated from the laminate.

(7) FIG. 6 shows a schematic representation of a next step of the invention in which two different embodiments of the rework system catch the defective tape.

(8) FIGS. 7 and 8 show a schematic representation of another embodiment in which the defective tape is firstly cut and afterwards the pressure roller is lifted from the laminate.

(9) FIG. 9 shows a schematic representation of a next step of the invention in which the rework system rewinds the tape for its removal.

(10) FIG. 10 shows a schematic representation of a next step of the invention in which the defective tape is replaced by a new one.

(11) FIG. 11 shows a schematic representation of an embodiment of the catching element of the rework system.

(12) FIG. 12 shows a schematic representation of the rewind step of the catching element of the embodiment of FIG. 11.

(13) FIG. 13 shows a schematic representation of the release step of the catching element of the embodiment of FIG. 11.

(14) FIG. 14 shows a schematic representation of the removal step of the catching element of the embodiment of FIG. 11.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(15) FIG. 1 discloses a known automated taped placement machine manufacturing a laminate (1) over a mold (100) by laminating tapes (2) by means of two heads comprising at least a pressure roller (6), addition rollers (5) and cutters (50). In FIG. 2 the tape (2) is clamped using the adding rollers (5) and cut using a blade or alternative system to end the laying.

(16) FIG. 3 shows the detection of a defect (3) on a tape (4) while the tape (4) is being laid up. Afterwards, the lay-up of the defective tape (4) is continued until a tape (4) length that surpasses the manufacturing length (L) of the tape (4) is achieved as represented in FIG. 4. By rotation of the adding rollers (5) the defective tape (4) is placed between the pressure roller (6) and the laying surface to continue the laying operation.

(17) In a multi-head machine, when laying multiple tapes (2), all the tapes (2) except the defective ones (4) are laid and cut according to the length of the original design of the part, except the defective ones (4) and those that may be selected to be also removed, that are extended an additional length. Therefore, the automated tape placement machine, once a signal of a defected tape (4) is received, continues the lay-up of a defective tape (4) until a tape (4) length is obtained that surpasses the manufacturing length (L) of the tape (4).

(18) In an embodiment, the catching system is deployed after detecting the occurrence of a defect (3) and retracted after removal of the defective tape (4). For allowing the mentioned deployment of the catching system, the laying head may be separated from the defective tape (4), more specifically, as shown in FIG. 5, the pressure roller (6) is lifted from the laminate (1).

(19) The catching system of the embodiment shown in FIG. 6 comprises a clamp (7) with two jaws which traps the defective tape (4) to allow its removal. FIG. 6 discloses two different embodiments, the clamp (7) being located below the pressure roller (6) or the clamp (7) being located over the pressure roller (6).

(20) The deployment of the jaws of the clamp (7) can be done by a longitudinal sliding movement, a rotational one, a telescopic extension or any other movement or combination of movements. These movements can be electric, pneumatic or any alternative considered appropriate.

(21) As previously commented, the catching step and the cutting step may be performed in any order: once the defective tape (4) or tapes (4) are clamped, the cutter (50) cuts them according to FIG. 6, or alternatively, the defective tapes (4) to be removed are firstly cut and afterwards are clamped according to FIGS. 7 and 8.

(22) The removal of the defective tape (4) will be done by rewinding the defective tape (4) around the clamp (7) as shown in FIG. 9, preferably at a speed coordinated with the backwards movement of the lying head. Finally, a replacement tape (2) is laid-up by the automated tape placement machine after removal of the defective tape (4) as shown in FIG. 10.

(23) As represented in the embodiment shown in FIGS. 11 to 14, in order to have the catching system always ready for the next rework operation, it is advisable to allow an automated release of the removed defective tape (4).

(24) In one embodiment, the clamp (7) comprises two external shells (9) and two internal cores (8) located in the shells (9) located in an opposite configuration and that behave as a clamp to grab the defective tape (4). The internal cores (8) are movable with respect to the external shells (9) such that they trap the defective tape (4) in-between when they approach each other and release the defective tape (4) when they move away from each other. The clamp (7) comprises means for rewinding the defective tape (4) around the clamp (7), specifically, the defective tape (4) will be rewound around the external shells (9) when the clamp (7) turns.

(25) FIG. 11 shows a first step in which the clamp (7) has both internal cores (8) separated so that the defective tape (4) is located in-between. FIG. 12 shows the internal cores (8) located against each other so that the defective tape (4) is caught by them and the turning of the clamp (7) makes the defective tape (4) rewind over the external shells (9). FIG. 13 shows the retraction of the inner cores (8) into the external shells (9) therefore liberating the defective tape (4).

(26) Finally, FIG. 14 shows one of the possible embodiments for releasing the defective tape (4) from the clamp (7) using a sliding arm (10) moving between the internal cores (8) in a direction parallel to the turning axis of the clamp (7) so that the sliding arm (10) pushes out the rolled defective tape (4).

(27) The release and remove steps would be preferably done in a scrap area located in the laying zone or integrated in the head or the structure of the machine, this last option reduces the number of movements of the machine but increase the size, weight and complexity of the machine so the solution will be adapted to each case.

(28) While at least one exemplary embodiment of the present invention(s) is disclosed herein, it should be understood that modifications, substitutions and alternatives may be apparent to one of ordinary skill in the art and can be made without departing from the scope of this disclosure. This disclosure is intended to cover any adaptations or variations of the exemplary embodiment(s). In addition, in this disclosure, the terms “comprise” or “comprising” do not exclude other elements or steps, the terms “a” or “one” do not exclude a plural number, and the term “or” means either or both. Furthermore, characteristics or steps which have been described may also be used in combination with other characteristics or steps and in any order unless the disclosure or context suggests otherwise. This disclosure hereby incorporates by reference the complete disclosure of any patent or application from which it claims benefit or priority.