Supporting formed sheets of material during machining operations

Abstract

The invention relates to supporting a formed sheet of material during a processing operation. In particular, a processing support is provided, which is configured to reduce the springback of the sheet after the processing operation is performed on the sheet. The processing support includes: a porous material having a plurality of surfaces, the plurality of surfaces including a support surface having a contour, the contour being configured to contact and support the sheet; a sealing material covering each of the plurality of surfaces except the support surface; and a vacuum port configured to provide a vacuum to the porous material.

Description

Technical Field

[0001] The present disclosure relates generally to performing machining operations on sheets of material and, more particularly, to supporting sheets of material during machining operations. Background Art

[0002] During the manufacture of sheet components, machining operations such as drilling or milling may be performed on a pre-formed sheet of material. Initial machining forces from the drill bit on the unsupported portion of the sheet and the resulting springback of the sheet may result in less than desired hole quality. Initial machining forces from the drill bit and the resulting springback of the sheet may undesirably affect the drill bit, including potentially damaging the drill bit.

[0003] Therefore, it would be desirable to have methods and apparatus that take into account at least some of the issues discussed above, as well as other possible issues. Summary of the invention

[0004] Exemplary embodiments of the present disclosure provide a method for reducing spring back of a sheet of material after a processing operation is performed on the sheet of material. A vacuum is drawn across a porous material of a processing support to hold a second surface of the sheet of material against a support surface of the processing support, the porous material of the processing support being sealed on all surfaces except the support surface. A vacuum is maintained within the porous material while a processing operation is performed across a first surface opposite the second surface of the sheet of material.

[0005] Another exemplary embodiment of the present disclosure provides a method for reducing springback of a sheet material after a processing operation is performed on the sheet material. A second surface of the sheet material is placed in contact with a support surface of a processing support, the processing support comprising a porous material sealed to each surface of the processing support except the support surface. A vacuum is drawn across the porous material to hold the second surface against the support surface. A processing operation is performed through a first surface of the sheet material opposite the second surface. A vacuum is maintained within the porous material while the processing operation is performed.

[0006] Another exemplary embodiment of the present disclosure provides a processing support configured to reduce springback of a sheet after a processing operation is performed on the sheet. The processing support includes: a porous material having a plurality of surfaces, the plurality of surfaces including a support surface having a contour, the contour being configured to contact and support the sheet; a sealing material covering each of the plurality of surfaces except the support surface; and a vacuum port configured to provide a vacuum to the porous material.

[0007] Another exemplary embodiment of the present disclosure provides a method of forming a processing support configured to reduce springback of a sheet after a processing operation is performed on the sheet. A porous material is formed to produce a plurality of surfaces including a support surface having a profile configured to contact and support the sheet. A sealing material is applied to each of the plurality of surfaces other than the support surface.

[0008] These features and functions can be achieved independently in various embodiments of the present disclosure or may be combined in yet other embodiments, in which further details can be seen with reference to the following description and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The novel features which are believed to be characteristic of the exemplary embodiments are set forth in the appended claims. However, the exemplary embodiments and their preferred modes of use, further objects and features thereof will be apparent from and will be understood in conjunction with the appended claims. Figure 1 The present disclosure is best understood when read with reference to the following detailed description of exemplary embodiments of the present disclosure, in which:

[0010] Figure 1 is an illustration of a block diagram of a tooling support configured to reduce springback following a tooling operation in a manufacturing environment for use in accordance with an illustrative embodiment;

[0011] Figure 2 is an illustration of a cross-sectional view of a sheet on a tooling support configured to reduce springback after a tooling operation according to an exemplary embodiment;

[0012] Figure 3 is an illustration of a cross-sectional view of a sheet on a tooling support after a tooling operation has been performed on the sheet according to an exemplary embodiment;

[0013] Figure 4 is an illustration of a cross-sectional view of a tooling support having features in a support surface according to an exemplary embodiment;

[0014] Figure 5 is an illustration of a cross-sectional view of a portion of a tooling support during a tooling operation performed on a sheet supported by the tooling support according to an exemplary embodiment;

[0015] Figure 6 is an illustration of a cross-sectional view of a portion of a tooling support during a tooling operation performed on a sheet supported by the tooling support according to an exemplary embodiment;

[0016] Fig. 7A and Figure 7B is an illustration of a flow chart of a method for reducing springback of a sheet material after a processing operation is performed on the sheet material according to an exemplary embodiment;

[0017] Figure 8 is an illustration of a flow chart of a method for forming a tooling support configured to reduce springback of a sheet material after a tooling operation is performed on the sheet material, according to an exemplary embodiment;

[0018] Fig. 9 is an illustration of a flow chart of a method for reducing springback of a sheet material after a processing operation is performed on the sheet material according to an exemplary embodiment;

[0019] Fig.10 is an illustration of an aircraft manufacturing and service method in block diagram form according to an illustrative embodiment; and

[0020] Fig.11 is an illustration of an aircraft in block diagram form in which illustrative embodiments may be implemented. DETAILED DESCRIPTION

[0021] The illustrative embodiments recognize and take into account one or more different considerations. The illustrative embodiments recognize and take into account that prior to processing the sheet, the sheet is constrained against a back-plate support tool. Typically, the sheet is constrained at the periphery, and the remainder of the sheet is unconstrained so that the constraint does not hinder processing. While constraining the periphery of the sheet, the remainder of the sheet may bend so that portions of the sheet are not in contact with the support surface of the support tool. The portions of the sheet that are not in contact with the support surface are not supported. While the periphery of the sheet is constrained against the support tool, a processing operation is performed on a portion of the sheet. The portion of the sheet to be processed may not contact the support tool and may be unsupported.

[0022] The illustrative embodiments recognize and take into account that performing a machining operation on an unsupported portion of a sheet of material results in springback. For example, when drilling a hole using a conventional drill press system, the drill bit first contacts the unsupported surface of the sheet of material and applies pressure to the sheet. The pressure or machining force applied from the drill bit first causes the sheet to press against the support tool before penetrating the sheet. Once the sheet is fully penetrated, the elastic energy causes the sheet to quickly spring back to its free state. This springback of the sheet is uncontrolled.

[0023] During the processing operation, the processing force of the drill bit pushes the sheet in the direction of the supporting tool. After the drill bit passes through the sheet, the sheet is no longer subjected to the pushing processing force of the drill bit, and the sheet rebounds to its original position.

[0024] For example, the illustrative embodiments recognize and take into account that the support tool desirably complements the shape of the sheet. The illustrative embodiments recognize and take into account that the support tool may not precisely complement the shape of the sheet across the entire support tool. The illustrative embodiments recognize and take into account that the support surface of the support tool may be non-planar to support the sheet. The illustrative embodiments recognize and take into account that constraining the sheet to the support tool may result in a gap between the support surface and the sheet.

[0025] The illustrative embodiments recognize and take into account that the support surface of the support tool can be non-planar to support the sheet. The illustrative embodiments recognize and take into account that the support surface of the support tool can be concave to support the sheet. When the support surface is concave, the periphery of the sheet is constrained so that the remainder of the sheet is bent so that a portion of the sheet is not in contact with the support surface of the support tool. The illustrative embodiments recognize and take into account that the combination of the shape of the sheet and the shape of the support tool may result in a gap between the sheet and the support tool. The illustrative embodiments recognize and take into account that the gap may occur even when there is potential rebound energy in the sheet.

[0026] The illustrative embodiments also recognize and take into account that in order to reduce the rebound of the material sheet, the contact between the sheet and the support tool can be increased. The rebound of the sheet is the recovery of the sheet to its original shape when the force is removed from the sheet. By maintaining the contact between the sheet and the tool, the rebound of the sheet after the processing operation is reduced or eliminated. By maintaining the contact between the sheet and the tool, the sheet generally maintains its shape before and as the processing force is applied to the sheet. By maintaining the contact between the sheet and the tool, the rebound of the sheet is restrained until the processing operation is completed and the sheet is released from the support tool.

[0027] The illustrative embodiments recognize and take into account that performing a machining operation on an unsupported portion of a sheet may result in an undesirable location of the machining operation. The illustrative embodiments recognize and take into account that in order to achieve a desired location of features created during a machining operation, it may be desirable to contact the sheet with a support surface.

[0028] The illustrative embodiments also recognize and take into account that, in order to reduce springback, a temporary adhesive may be used to attach the material sheet to the support tool. However, adhesive residue may be transferred to the processing tool, such as a drill bit. Adhesive residue on the processing tool may undesirably affect at least one of the life of the processing tool or the quality of the manufactured component. For example, adhesive residue may undesirably affect the quality of the drilled hole in the manufactured component. The illustrative embodiments recognize and take into account that applying adhesive increases the time and cost of the manufacturing process.

[0029] Additionally, the adhesive used to hold the sheet of material to the support tool will be qualified for use in contact with the type of material of the sheet and the material of the support tool. It would be undesirable to use an adhesive that would damage either the material of the sheet or the material of the support tool. Depending on the material of the sheet, there may be a limited number of qualified adhesives.

[0030] In some manufacturing operations, vacuum is applied to the sheet to hold the sheet against a support tool. However, conventional vacuum panels with vacuum channels around the periphery do not apply vacuum to the center of the sheet where the processing operation is performed. Processing operations such as perforation processes will reduce the effectiveness of conventional vacuum panels with vacuum channels in the area of ​​the processing operation.

[0031] The illustrative embodiments recognize and take into account that conventional methods of attempting to reduce springback include methods of holding the sheet against a support tool. Conventional methods of attempting to reduce springback include methods of increasing the support surface of the sheet at the periphery of the sheet.

[0032] Exemplary embodiments provide a processing support and method for reducing springback during processing operations. Exemplary embodiments use a processing support formed of a porous material to support a sheet. By using a vacuum to hold the sheet against the support surface, springback of the sheet after the processing operation is reduced or eliminated.

[0033] Now go to Figure 1 , an illustration of a block diagram of a tooling support configured to reduce springback after a tooling operation in a manufacturing environment is depicted in accordance with an illustrative embodiment. A manufacturing environment 100 has a tooling support 102 that supports a sheet 104 while a tooling operation 106 is performed on the sheet 104 by a tooling tool 108.

[0034] The processing support 102 is configured to reduce springback of the sheet 104 after the processing operation 106 is performed on the sheet 104. The processing support 102 includes: a porous material 110 having a plurality of surfaces 112, the plurality of surfaces including a support surface 114 having a profile 116, the profile 116 being configured to contact and support the sheet 104; a sealing material 118, the sealing material covering each of the plurality of surfaces 112 except the support surface 114; and a vacuum port 120, the vacuum port being configured to provide a vacuum 122 to the porous material 110.

[0035] The sealing material 118 on the outer surface 124 prevents the vacuum 122 from escaping through the outer surface 124. The vacuum 122 will escape through the support surface 114 to hold the sheet 104 against the support surface 114.

[0036] In some illustrative examples, there are indentations 126 in support surface 114. In these illustrative examples, indentations 126 correspond to locations where machining operations are performed on sheet 104. In these illustrative examples, indentations 126 correspond to locations of number of features 128 of sheet 104. As used herein, a "number" of items is one or more items. Thus, number of features 128 is one or more features. In these illustrative examples, an indentation corresponds to a feature when machining tool 108 can extend through the feature and into the indentation.

[0037] In some illustrative examples, indentation 126 is formed by performing machining operation 106 on sheet 104. For example, when machining operation 106 is drilling 130 hole 132 in sheet 104, indentation 126 is formed by drilling hole 130 extending through sheet 104 and impacting porous material 110.

[0038] In some other illustrative examples, each dimple 126 is larger than a corresponding feature in number of features 128 to be machined into sheet 104. When each dimple 126 is larger than the corresponding feature to be machined into sheet 104, machining operation 106 will not remove material from support surface 114. When each dimple 126 is larger than the corresponding feature to be machined into sheet 104, machining tolerances are taken into account.

[0039] After forming indentations 126 in support surface 114, sealing material 134 is placed within each indentation 126. In some illustrative examples, indentations 126 are formed and filled with sealing material 134 before sheet 104 is placed on support surface 114. In some illustrative examples, indentations 126 are formed while sheet 104 is on support surface 114, and indentations 126 are sealed with sealing material 134 after sheet 104 is removed from tooling support 102.

[0040] The porous material 110 takes any desired form. In some illustrative examples, the porous material 110 is an open-cell foam. In some illustrative examples, the porous material 110 is an artificial wood. The porous material 110 is selected to allow the vacuum 122 to travel through the processing support 102 and escape through the support surface 114. The physical properties of the porous material 110, including the porosity, act as a distribution system for the vacuum 122 to travel through the porous material 110. The processing support 102 is formed of the porous material 110, and the porosity of the porous material 110 acts as a distribution system for the vacuum 122 to travel through the processing support 102.

[0041] Sheet 104 is supported by support surface 114 while processing operation 106 is performed on sheet 104. Processing operation 106 is used to form number of features 128 in sheet 104. Sheet 104 is formed of material 136. In some illustrative examples, material 136 takes the form of any desired material having elastic deformation 138. Elastic deformation 138 is the ability of material 136 to temporarily change shape when a force is applied. When the force is removed, elastic deformation 138 allows material 136 to return to its original shape. In some illustrative examples, material 136 is one of metal 140 or composite material 142. When material 136 is composite material 142, composite material 142 is cured or partially cured.

[0042] In some illustrative examples, sheet 104 is referred to as thin sheet 144. Sheet 104 may be referred to as thin sheet 144 because sheet 104 is thin enough to deflect when pressure from machining operation 106 is applied to sheet 104 without machining support 102 having support surface 114. In some illustrative examples, when sheet 104 is a composite material 142 such as a CFRP laminate, the thickness of material 136 is between 0.020" and 0.100". In addition to the thickness of sheet 104, the number of layers and orientation of fibers in composite material 142 also affect the deflection of sheet 104. Composite materials having the same thickness but different layups may deflect to different degrees.

[0043] When vacuum 122 is provided to porous material 110 of tooling support 102, sheet 104 is held against support surface 114. Profile 116 of support surface 114 is configured to support bend 148. Support surface 114 is configured to support entire second surface 150, not just perimeter 146.

[0044] While sheet 104 is held against support surface 114, machining operation 106 is performed on sheet 104 to form number of features 128. Machining operation 106 is performed across first surface 152 of sheet 104. First surface 152 is opposite second surface 150. In some illustrative examples, first surface 152 is referred to as a front surface of sheet 104, and second surface 150 is referred to as a back surface of sheet 104.

[0045] Machining operation 106 is any desired operation. In some illustrative examples, machining operation 106 is drilling 130. In some illustrative examples, machining operation 106 is routing 154. Machining operation 106 forms number of features 128.

[0046] The number of features 128 can take any desired form. The number of features 128 include holes 132 or other shapes, such as channels 156 or slots 158. In some illustrative examples, the number of features 128 are each within a size range of 0.020" to 0.300". In some illustrative examples, the number of features 128 are arranged in a repeating pattern to achieve a consistent percentage of open area. The open area is the ratio of the amount of the number of features 128 occupying the first surface 152. In some illustrative examples, the pattern of the number of features 128 has a percentage open area in the range of 5% open area to 30% open area based on the design criteria of the component 162.

[0047] Number of features 128 are formed in region 160. In some illustrative examples, if sheet 104 were constrained only at periphery 146, performing machining operation 106 in region 160 would result in springback. By supporting more of second surface 150 than just periphery 146, springback of sheet 104 after machining operation 106 is performed in region 160 is reduced or eliminated.

[0048] Processing tool 108 performs processing operation 106 on sheet 104 to form component 162. Component 162 is a component of any desired type of platform. The platform can be, for example, a vehicle, a mobile platform, a fixed platform, a land-based structure, a water-based structure, or a space-based structure. More specifically, the platform can be a surface ship, a tank, a personnel carrier, a train, a spacecraft, a space station, a satellite, a submarine, a car, a power plant, a bridge, a dam, a house, a manufacturing facility, a building, or other suitable platform. In some illustrative examples, the platform takes the form of an aircraft. In these illustrative examples, component 162 is an aircraft component 164.

[0049] Component 162 has at least one feature formed by machining tool 108 during machining operation 106. For example, component 162 may have a plurality of slots, a plurality of channels, a plurality of holes, or any other desired feature. In some illustrative examples, component 162 is a perforated component. In some illustrative examples, component 162 takes the form of damper 166. Damper 166 may be an acoustic damper, a pressure damper, or any other type of damper.

[0050] Figure 1 The illustration of manufacturing environment 100 and processing support 102 in the example is not meant to imply physical or architectural limitations on the manner in which the illustrative embodiments can be implemented. Components other than the illustrated components or other components in place of the illustrated components may be used. Some components may not be necessary. Moreover, blocks are presented to illustrate some functional components. One or more of these blocks may be combined, divided, or combined and divided into different blocks when implemented in the illustrative embodiments.

[0051] For example, while component 162 is depicted as damper 166, component 162 may take any desired form. In some illustrative examples, component 162 is an aesthetic panel used to decorate the interior or exterior of a platform.

[0052] Now go to Figure 2 , depicts an illustration of a cross-sectional view of a sheet on a tooling support configured to reduce springback after a tooling operation according to an illustrative embodiment. In view 200, sheet 202 is held against tooling support 204. Tooling support 204 is configured to reduce springback of sheet 202 after tooling operation 106 is performed on sheet 202. Tooling support 204 is Figure 1 The processing support 204 includes a porous material 206 having a plurality of surfaces 208. The plurality of surfaces 208 include a support surface 210 having a profile 212 configured to contact and support the sheet 202. A sealing material 214 covers each of the plurality of surfaces 208 except the support surface 210. A vacuum port 216 is configured to provide a vacuum to the porous material 206.

[0053] The sealing material 214 prevents the vacuum from escaping through the plurality of surfaces 208 other than the support surface 210. For example, the sealing material 214 on the outer surface 218 prevents the vacuum from escaping the outer surface 218. As another example, the sealing material 214 on the outer surface 220 prevents the vacuum from escaping the outer surface 220. The vacuum port 216 extends through the sealing material 214 of the outer surface 222.

[0054] Porous material 206 takes any desired form to deliver a vacuum throughout tooling support 204. In some illustrative examples, porous material 206 is an open-cell foam. In another illustrative example, porous material 206 is an artificial wood.

[0055] The vacuum supplied through the vacuum port 216 and distributed through the porous material 206 holds the sheet 202 against the support surface 210. More specifically, the second surface 224 of the sheet 202 is held against the support surface 210. While the second surface 224 of the sheet 202 is held against the support surface 210, machining operations may be performed through the first surface 226.

[0056] When sheet 202 is held against support surface 210, sheet 202 and tooling support 204 form a vacuum chamber. As depicted, porous material 206 is free of any indentations. If a tooling operation extended through sheet 202, indentations would be formed into porous material 206. If indentations were formed into porous material 206 during a tooling operation, the vacuum would escape through the indentations.

[0057] Figure 2 The illustration of processing support 204 in FIG. 1 is not meant to imply physical or architectural limitations to the manner in which an illustrative embodiment may be implemented. Other components in addition to or in place of the ones illustrated may be used.

[0058] For example, profile 212 of support surface 210 may have any desired shape to support sheet 202. In some illustrative examples, sheet 202 may have a shape similar to Figure 2 In these illustrative examples, support surface 210 has a curvature different from that depicted. Figure 2 210 , so that the support surface 210 reflects the curvature of the sheet 202. The profile 212 of the support surface 210 is configured to support and contact the sheet 202 so that the sheet 202 contacts the support surface 210 in the area where the manufacturing operation will be performed. As another illustrative example, the vacuum port 216 can be located in a different location from the outer surface 222. For example, the vacuum port 216 can be located in the outer surface 218. As another illustrative example, the vacuum port 216 can be located in a different location within the outer surface 222. As another illustrative example, the vacuum port 216 can be located in the outer surface 220.

[0059] Now go to Figure 3 , depicts an illustration of a cross-sectional view of a sheet on a processing support after a processing operation is performed on the sheet according to an illustrative embodiment. View 300 is a view of sheet 202 after a processing operation is performed. In view 300, sheet 202 has a number of features 302. The number of features 302 may be a plurality of holes or a plurality of slots. In some illustrative examples, sheet 202 may be referred to as a perforated sheet.

[0060] As depicted, the machining operations performed on sheet 202 have produced indentations 304 in machining support 204. As depicted, indentations 304 in support surface 210 correspond to the locations of the machining operations performed on sheet 202. As depicted, indentations 304 in support surface 210 correspond to the locations of number of features 302.

[0061] Figure 3 The illustration of features 302 and indentations 304 in sheet 202 is not meant to imply physical or architectural limitations to the manner in which the illustrative embodiments may be implemented. For example, the number, size, and location of features 302 in sheet 202 are not meant to imply physical or architectural limitations. Features 302 may have any desired number, size, location, and type of features.

[0062] Now go to Figure 4 , depicts an illustration of a cross-sectional view of a tooling support having features in a support surface according to an exemplary embodiment. Tooling support 400 is Figure 1 The tooling support 400 may be the same as the tooling support 204 having the indentation 304.

[0063] The processing support 400 is configured to reduce springback of the sheet after a processing operation is performed on the sheet. The processing support 400 includes a porous material 402 having a plurality of surfaces 404. The plurality of surfaces 404 includes a support surface 406 having a profile 408, which is configured to contact and support the sheet. A sealing material 410 covers each of the plurality of surfaces 404 except the support surface 406. A vacuum port 412 is configured to provide a vacuum to the porous material 402.

[0064] Sealing material 410 prevents the vacuum from escaping through multiple surfaces 404 other than support surface 406. For example, sealing material 410 on outer surface 414 prevents the vacuum from escaping outer surface 414. As another example, sealing material 410 on outer surface 416 prevents the vacuum from escaping outer surface 416. Vacuum port 412 extends through sealing material 410 of outer surface 418.

[0065] Porous material 402 takes any desired form to deliver a vacuum throughout tooling support 400. In some illustrative examples, porous material 402 is an open-cell foam. In another illustrative example, porous material 402 is an artificial wood.

[0066] A vacuum supplied through vacuum port 412 and extending through porous material 402 will hold sheet 202 against support surface 406. Tooling support 400 includes indentations 420 in support surface 406 that correspond to the locations of tooling operations on the sheet.

[0067] In some illustrative examples, each indentation 420 is larger than a corresponding feature to be machined into the sheet. In this illustrative example, sealing material 422 is within each indentation 420.

[0068] The sheet and tooling support 400 form a vacuum chamber when the sheet is held against support surface 406. With indentations 420 sealed by sealing material 422, the vacuum chamber is maintained throughout tooling operations for corresponding features machined into the sheet.

[0069] Now go to Figure 5 , depicts an illustration of a cross-sectional view of a portion of a tooling support during a tooling operation performed on a sheet supported by the tooling support, according to an exemplary embodiment. Tooling support 500 is Figure 1 In some illustrative examples, view 502 is a physical implementation of processing support 102. Figure 2 and Figure 3A view of a machining operation performed on a portion of sheet 202 .

[0070] Tooling support 500 has support surface 504. Sheet 506 is held against support surface 504 of tooling support 500 by vacuum 507 applied to porous material 508 of tooling support 500. In view 502, feature 510 has been machined into sheet 506. The machining operation that created feature 510 of sheet 506 forms indentation 512.

[0071] As can be seen in view 502, vacuum 507 escapes through indentation 512. The vacuum provided is adjusted so as to maintain vacuum 507 in porous material 508. In some illustrative examples, the vacuum provided to porous material 508 is adjusted to maintain a pressure differential across second surface 513 of sheet 506 so as to hold second surface 513 against support surface 504 of porous material 508 while performing a machining operation on sheet 506.

[0072] In view 502, a machining tool 514 performs a machining operation on sheet 506. As depicted, machining tool 514 extends through sheet 506 and forms indentations 516 into support surface 504. As depicted, machining tool 514 takes the form of a drill bit. Although not depicted, machining tool 514 may be attached to any desired machine, such as a drill press, a CNC machine, or any other desired machine.

[0073] Now go to Figure 6 , depicts an illustration of a cross-sectional view of a portion of a tooling support during a tooling operation performed on a sheet supported by the tooling support, according to an exemplary embodiment. Tooling support 600 is Figure 1 Physical realization of the processing support 102.

[0074] In view 602, tooling support 600 has support surface 604. Sheet 606 is held against support surface 604 of tooling support 600 by vacuum 607 applied to porous material 608 of tooling support 600. In view 602, features 610 have been machined into sheet 606. Indentations 612 and 614 are formed into porous material 608 prior to holding sheet 606 against support surface 604. In some illustrative examples, indentations 612 and 614 are formed into porous material 608 while tooling operations are being performed on a different sheet (not depicted). In other illustrative examples, indentations 612 and 614 are formed into porous material 608 while tooling support 600 is being manufactured.

[0075] Both the indentation 612 and the indentation 614 are sealed with a sealing material 616. The sealing material 616 generally confines or prevents a vacuum from escaping the indentation 612 and the indentation 614.

[0076] In view 602, machining tool 618 performs a machining operation on sheet 606. As depicted, machining tool 618 extends through sheet 606 but does not contact support surface 604. As depicted, machining tool 618 does not contact porous material 608 of machining support 600. Indents 612 and 614 are larger than feature 610. By making indents 612 and 614 larger than feature 610 and machining tool 618, machining tool 618 performs a machining operation to form feature 610 without contacting porous material 608. In some illustrative examples, indents 612 and 614 are sized to account for tolerances in the machining operation performed by machining tool 618.

[0077] Now go to Fig. 7A and Figure 7B , depicts an illustration of a flow chart of a method for reducing springback of a sheet material after a processing operation is performed on the sheet material, according to an exemplary embodiment. The method 700 may be used Figure 1 Method 700 may be implemented using a processing support 102 in a manufacturing environment 100. Figure 2 The method 700 can be implemented as follows: Figure 2 and Figure 3 The processing operation is performed on the sheet 202. The method 700 may be used Figure 4 The method 700 can be implemented using the processing support 500. Figure 5 Method 700 may use machining support 600 to Figure 6 is implemented in .

[0078] Method 700 places a second surface of a sheet in contact with a support surface of a machining support, the machining support including a porous material sealed on each surface of the machining support except the support surface (operation 702). In some illustrative examples, when the second surface of the sheet is placed in contact with the support surface, only a portion of the second surface of the sheet is placed in contact with the support surface of the machining support. In some illustrative examples, when the sheet has a curvature, the periphery or center of the sheet is not in contact with the support surface.

[0079] The method 700 draws a vacuum across the porous material to hold the second surface against the support surface (operation 704). Due to the seal on the remaining surface of the processing support, a vacuum can be drawn across the porous material. The vacuum extends through the support surface and holds the second surface against the support surface.

[0080] Method 700 performs a machining operation through the first surface of the sheet opposite the second surface (operation 706). The machining operation is any desired operation. The machining operation can be drilling, milling, or any other desired type of operation.

[0081] The method 700 maintains a vacuum within the porous material while performing the machining operation (operation 708). By maintaining the vacuum within the porous material while performing the machining operation, the mechanical forces from the machining operation do not deflect the sheet. When the machining operation is performed on the sheet, the sheet is in contact with the support surface and does not deflect. The rebound of the sheet is the recovery of the sheet to its original shape when the force is removed from the sheet. By maintaining contact between the second surface of the sheet and the support surface, the rebound of the sheet after the machining operation is reduced or eliminated. By maintaining contact between the second surface of the sheet and the support surface, the sheet generally maintains its shape before and as the machining force is applied to the sheet. Then, the method 700 terminates.

[0082] In some illustrative examples, as the tooling operation is performed on the sheet, an indentation is formed in the tooling support. In some illustrative examples, the vacuum is maintained by adjusting a vacuum provided as the indentation is formed in the tooling support.

[0083] In some illustrative examples, performing the machining operation through the first surface includes drilling a hole in the sheet (operation 710). In some illustrative examples, performing the machining operation also includes machining an indentation into a support surface of a machining support as the machining operation is performed through the first surface of the sheet (operation 712).

[0084] In some illustrative examples, method 700 applies a sealing material into each indentation in the support surface (operation 714). In some illustrative examples, the sealing material is placed into each indentation in a sealing process after each indentation has been formed. In this illustrative example, the sealing material is applied after the sheet is removed from the support surface. When the sealing material is applied into each indentation, vacuum is not lost from the indentation. When the sealing material is applied into each indentation, the processing support can be used to support another sheet.

[0085] In some illustrative examples, process 700 adjusts the vacuum provided to the porous material to maintain a pressure differential across the second surface of the sheet to hold the second surface against the support surface of the porous material while performing a machining operation on the sheet (operation 716 ).

[0086] In some illustrative examples, performing the machining operation includes machining indentations into a support surface of a machining support as holes are drilled into the sheet (operation 718), and the method 700 applies a sealing material within each indentation in the support surface before a vacuum is drawn across the porous material to hold the second sheet against the support surface (operation 720). In some illustrative examples, the sealing material is placed into each indentation in a sealing process after each indentation has been formed. In this illustrative example, the sealing material is applied after the sheet is removed from the support surface. When the sealing material is applied within each indentation, vacuum is not lost from the indentation. When the sealing material is applied within each indentation, the machining support can be used to support other sheets, including the second sheet.

[0087] In some illustrative examples, method 700 releases the vacuum from the porous material of the tooling support (operation 722). In some illustrative examples, method 700 removes the sheet having the features created by the tooling operation from the tooling support after releasing the vacuum (operation 724). In some illustrative examples, method 700 draws a vacuum across the porous material to hold the second sheet against the support surface (operation 726). In some illustrative examples, method 700 performs the tooling operation on the second sheet while maintaining the vacuum within the porous material (operation 728).

[0088] Now go to Figure 8 , depicts an illustration of a flow chart of a method for forming a tooling support configured to reduce springback of a sheet material after a tooling operation is performed on the sheet material, according to an exemplary embodiment. Method 800 may be implemented to form Figure 1 The method 800 may be implemented to form a processing support 102 in the Figure 2 and Figure 3 The method 800 may be implemented to form a processing support 204. Figure 4 The method 800 may be implemented to form a processing support 400. Figure 5 The method 800 may be implemented to form a processing support 500. Figure 6 The processing support 600 in the embodiment of the present invention.

[0089] Method 800 shapes a porous material to create a plurality of surfaces, the plurality of surfaces including a support surface having a profile configured to contact and support a sheet of material (operation 802). Method 800 applies a sealing material to each of the plurality of surfaces except the support surface (operation 804). By sealing the plurality of surfaces, the applied vacuum will not escape through the sealing surface of the processing support. By not sealing the support surface, the vacuum applied to the porous material will escape through the support surface to hold the sheet of material against the support surface. Then, method 800 terminates.

[0090] In some illustrative examples, method 800 machines indentations into the support surface (operation 806). In some illustrative examples, the indentations are machined into the support surface prior to placing the sheet onto the support surface.

[0091] In some illustrative examples, method 800 applies a sealing material to each indentation (operation 808). The sealing material within each indentation prevents the vacuum from escaping through the indentation. The sealing material within each indentation only allows the vacuum to escape through the support surface of the processing support.

[0092] In some illustrative examples, each indentation is larger than a corresponding feature to be machined into the sheet (operation 810). When each indentation is larger than a corresponding feature to be machined into the sheet, the machining operation will not remove material from the support surface. When each indentation is larger than a corresponding feature to be machined into the sheet, machining tolerances are taken into account.

[0093] In some illustrative examples, machining the indentations into the support surface is performed during a machining operation on the sheet material, and applying the sealing material (operation 812 ) is performed after the sheet material is removed from the support surface.

[0094] In some illustrative examples, method 800 inserts a vacuum port into the porous material (operation 814). The vacuum port provides access through one of the sealing surfaces to draw a vacuum on the porous material.

[0095] Now go to Fig. 9 , depicts an illustration of a flow chart of a method for reducing springback of a sheet material after a processing operation on the sheet material, according to an exemplary embodiment. The method 900 may be used Figure 1 Method 900 may be implemented using a processing support 102 in a manufacturing environment 100. Figure 2 The method 900 can be implemented as follows: Figure 2 and Figure 3 The method 900 may be used to perform a processing operation on the sheet 202. Figure 4 The method 900 can be implemented using the processing support 500. Figure 5 Method 900 may use machining support 600 to Figure 6 is implemented in .

[0096] The method 900 draws a vacuum across a porous material of a processing support to hold a second surface of the sheet against a support surface of the processing support, the porous material of the processing support being sealed on all surfaces except the support surface (operation 902). The method 900 maintains a vacuum within the porous material while performing a processing operation across a first surface of the sheet opposite the second surface (operation 904). The method 900 then terminates.

[0097] In some illustrative examples, method 900 adjusts the vacuum provided to the porous material to maintain a pressure differential across the second surface of the sheet material to hold the second surface against the support surface of the porous material while performing the machining operation on the sheet material (operation 906). In some illustrative examples, performing the machining operation further includes machining indentations into the support surface of the machining support as the machining operation is performed across the first surface of the sheet material (operation 908). In some illustrative examples, method 900 applies a sealing material within each of the indentations in the support surface (operation 910).

[0098] As used herein, the phrase "at least one of" when used with a list of items means that different combinations of one or more of the items in the list may be used, and only one of each item in the list may be required. In other words, "at least one of" means that any combination of items and any number of items from the list may be used, but not all items in the list are required. An item may be a specific object, thing, or category.

[0099] For example, "at least one of item A, item B, or item C" may include, without limitation, item A, item A and item B, or item B. This example may also include item A, item B, and item C, or item B and item C. Of course, any combination of these items may exist. In other examples, "at least one" may, for example, be, without limitation, two items A, one item B, and ten items C; four items B and seven items C; or other suitable combinations.

[0100] The flowcharts and block diagrams in the different depicted embodiments illustrate some possible implementation architectures, functions and operations of the devices and methods in the illustrative embodiments. In this regard, each block in the flowchart or block diagram may represent a module, a segment, a function and / or a part of an operation or a step.

[0101] In some alternative implementations of the illustrative embodiments, the functions annotated in the blocks may occur outside the order annotated in the drawings. For example, in some cases, two blocks shown in succession may be performed approximately simultaneously, or blocks may sometimes be performed in reverse order, depending on the functions involved. Similarly, in a flow chart or block diagram, in addition to the illustrated blocks, other blocks may be added. Some blocks may be optional. For example, in method 700, operations 710 to 728 may be optional. As another example, in method 800, operations 806 to 814 may be optional. As another example, in method 900, operations 906 to 910 may be optional.

[0102] Exemplary embodiments of the present disclosure may be implemented in Fig.10 Aircraft manufacturing and service method 1000 and the like are shown Fig.11The present invention will be described in the context of the aircraft 1100 shown. Fig.10 , an example of an aircraft manufacturing and service method is depicted according to an illustrative embodiment. During pre-production, aircraft manufacturing and service method 1000 may include Fig.11 Specification and design 1002 of the aircraft 1100 and material procurement 1004.

[0103] During production, component and subassembly manufacturing 1006 and system integration 1008 of the aircraft 1100 occurs. Thereafter, the aircraft 1100 may undergo certification and delivery 1010 for entry into service 1012. While serving 1012 customers, the aircraft 1100 may be scheduled for routine maintenance and servicing 1014, which may include modification, reconfiguration, refurbishment, or other maintenance and servicing.

[0104] The various processes of aircraft manufacturing and service method 1000 may be performed or carried out by a system integrator, a third party, and / or an operator. In these examples, the operator may be a customer. For the purposes of this description, a system integrator may include, without limitation, any number of aircraft manufacturers and major system subcontractors; a third party may include, without limitation, any number of vendors, subcontractors, and suppliers; and an operator may be an airline, a leasing company, a military entity, a maintenance organization, etc.

[0105] Now refer to Fig.11 , depicts an example of an aircraft in which an illustrative embodiment may be implemented. In this example, aircraft 1100 is comprised of Fig.10 1000 is produced by aircraft manufacturing and service method 1000 and may include airframe 1102 having multiple systems 1104 and interior 1106. Examples of systems 1104 include one or more of propulsion system 1108, electrical system 1110, hydraulic system 1112, and environmental system 1114. Any number of other systems may be included. Although an aerospace example is shown, different illustrative embodiments may be applied to other industries (such as the automotive industry).

[0106] Apparatus and methods embodied herein may be employed during at least one of the stages of aircraft manufacturing and service method 1000. Fig.10 One or more illustrative embodiments may be used during at least one of component and subassembly manufacturing 1006, system integration 1008, or maintenance and service 1014 of aircraft 1100. For example, tooling supports 102 may be used during component and subassembly manufacturing 1006 to form a component of aircraft 1100. As another illustrative example, tooling supports 102 may be used in maintenance and service 1014. Tooling supports 102 may be used to manufacture a portion of aircraft 1100, such as a portion of fuselage 1102 or interior 1106.

[0107] Illustrative examples provide methods and processing supports for holding thin sheets, such as thin CFRP laminates, during processing operations. Holding the sheet against the processing support keeps the sheet stable during processing operations, such as a robotic perforation process for sonication. In the illustrative examples, a vacuum source draws a vacuum through a porous medium or material formed into the curvature of the sheet to hold the sheet against the support surface of the processing support. The porous medium provides some local flow resistance so that when multiple holes or other features are punched in the laminate, the total vacuum on the sheet is not lost.

[0108] By holding the sheet to the tooling support with a vacuum, a uniform, intimate contact can be created across the sheet to stabilize it. By providing stability to the sheet, holes or other features in the sheet can be created with acceptable quality.

[0109] By maintaining a vacuum within the porous material while performing the machining operation, close contact is maintained between the sheet and the supporting surface. By maintaining contact between the sheet and the supporting surface, the machining forces from the machining operation do not deflect the sheet. When the machining operation is performed on the sheet, the sheet is in contact with the supporting surface and does not deflect. The rebound of the sheet is the return of the sheet to its original shape when the force is removed from the sheet. By maintaining contact between the second surface of the sheet and the supporting surface, the rebound of the sheet after the machining operation is reduced or eliminated. By maintaining contact between the second surface of the sheet and the supporting surface, the rebound of the sheet is controlled. By maintaining contact between the second surface of the sheet and the supporting surface, the sheet rebounds after the sheet is released from the supporting tool.

[0110] The sheet can be perforated for any desired purpose. In some illustrative examples, the sheet can be perforated for sonication. By using a porous material to constrain airflow across the support surface, the surface of the sheet can be perforated without a complete loss of vacuum, as occurs in conventional vacuum hold-down systems that rely on a seal-type vacuum zone.

[0111] Further, the present disclosure includes examples according to the following clauses:

[0112] Item 1. A method for reducing springback of a sheet of material after a processing operation is performed on the sheet of material, the method comprising the steps of: drawing a vacuum across a porous material of a processing support to hold a second surface of the sheet against a support surface of the processing support, the porous material of the processing support being sealed on all surfaces except the support surface; and maintaining a vacuum within the porous material while performing a processing operation through a first surface opposite to the second surface of the sheet of material.

[0113] Clause 2. The method of clause 1, further comprising the step of adjusting the vacuum provided to the porous material to maintain a pressure differential across the second surface of the sheet to hold the second surface against the support surface of the porous material while performing a processing operation on the sheet.

[0114] Clause 3. The method of clause 1 or 2, wherein performing the machining operation further comprises machining an indentation into a support surface of a machining support as the machining operation is performed across the first surface of the sheet.

[0115] Clause 4. The method of Clause 3, further comprising the step of applying a sealing material within each of the indentations in the support surface.

[0116] Clause 5. The method of any one of clauses 1 to 4, further comprising the step of placing the second surface of the sheet in contact with a support surface of a processing support.

[0117] Item 6. A method for reducing springback of a sheet of material after a processing operation is performed on the sheet of material, the method comprising the steps of: placing a second surface of the sheet of material in contact with a support surface of a processing support, the processing support comprising a porous material sealed to each surface of the processing support except the support surface; drawing a vacuum across the porous material to hold the second surface against the support surface; performing a processing operation through a first surface of the sheet of material opposite to the second surface; and maintaining a vacuum within the porous material while performing the processing operation.

[0118] Clause 7. The method of clause 5 or 6, wherein performing the machining operation further comprises machining an indentation into a support surface of a machining support as the machining operation is performed across the first surface of the sheet.

[0119] Clause 8. The method of Clause 7, further comprising the step of applying a sealing material within each of the indentations in the support surface.

[0120] Item 9. A method according to any one of items 5 to 8, the method further comprising at least one of the following steps: releasing the vacuum from the porous material of the processing support; after releasing the vacuum, removing the sheet having features created by the processing operation from the processing support; drawing a vacuum across the porous material to hold a second sheet against the support surface; and performing the processing operation on the second sheet while maintaining the vacuum within the porous material.

[0121] Clause 10. A method according to clause 9, wherein performing the machining operation includes machining indentations into a support surface of a machining support as features are created into the sheet, and the method further comprises the step of applying a sealing material within each indentation in the support surface before drawing a vacuum across the porous material to hold the second sheet against the support surface.

[0122] Clause 11. The method of any one of clauses 5 to 10, further comprising the step of adjusting the vacuum provided to the porous material to maintain a pressure differential across the second surface of the sheet to hold the second surface against the support surface of the porous material while performing a processing operation on the sheet.

[0123] Clause 12. The method of any one of clauses 5 to 11, wherein performing the machining operation through the first surface comprises drilling a hole through the sheet.

[0124] Item 13. A processing support configured to reduce springback of a sheet after a processing operation is performed on the sheet, the processing support comprising: a porous material having multiple surfaces, the multiple surfaces including a support surface having a contour configured to contact and support the sheet; a sealing material covering each of the multiple surfaces except the support surface; and a vacuum port configured to provide a vacuum to the porous material.

[0125] Clause 14. The processing support of Clause 13, the method further comprising: indentations in the support surface, the indentations corresponding to locations where processing operations are performed on the sheet.

[0126] Clause 15. The tooling support of Clause 14, wherein each indentation is larger than a corresponding feature to be tooled into the sheet.

[0127] Clause 16. The tooling support of Clause 14 or 15, further comprising: a sealing material within each indentation.

[0128] Clause 17. The processing support of any one of Clauses 13 to 16, wherein the porous material is an open cell foam.

[0129] Clause 18. The processing support of any one of clauses 13 to 16, wherein the porous material is artificial wood.

[0130] Item 19. A method of forming a processing support of any one of items 13 to 18, the method comprising the steps of: shaping a porous material to create a plurality of surfaces including a support surface, the support surface having a profile configured to contact and support a sheet; and applying a sealing material to each of the plurality of surfaces except the support surface.

[0131] Item 20. A method of forming a processing support configured to reduce springback of a sheet after a processing operation is performed on the sheet, the method comprising the steps of: forming a porous material to create a plurality of surfaces including a support surface having a profile configured to contact and support the sheet; and applying a sealing material to each of the plurality of surfaces except the support surface.

[0132] Clause 21. The method of clause 19 or 20, further comprising the steps of: machining dimples into the support surface; and applying a sealing material to each dimple.

[0133] Clause 22. The method of clause 21, wherein each indentation is larger than a corresponding feature to be machined into the sheet.

[0134] Clause 23. The method of clause 21 or 22, wherein machining the indentation into the support surface is performed during a machining operation on the sheet, and wherein applying the sealing material is performed after removing the sheet from the support surface.

[0135] Clause 24. The method of any one of clauses 19 to 23, further comprising the step of inserting a vacuum port into the porous material.

[0136] The description of different illustrative embodiments is presented for the purpose of illustration and description and is not intended to be exhaustive or limited to the embodiments in the disclosed form. Many modifications and variations will be apparent to those of ordinary skill in the art. Further, different illustrative embodiments may provide different features than other illustrative embodiments. The selected embodiments are chosen and described in order to best illustrate the principles of the embodiments, the practical application, and to enable others of ordinary skill in the art to understand the various embodiments of the present disclosure, as well as various modifications suitable for the specific use contemplated.

Claims

1. A method for reducing the springback of a sheet after a processing operation on the sheet, the method The following steps are involved: pulling a vacuum across the porous material of a tooling support to hold the second surface of the sheet against a support surface of the tooling support, the porous material of the tooling support being sealed on all surfaces except the support surface; maintaining the vacuum within the porous material while performing the machining operation through a first surface of the sheet opposite the second surface, machining indentations into the support surface of the machining support as the machining operation is performed through the first surface of the sheet; as well as A sealing material is applied within each of the indentations in the support surface.

2. The method according to claim 1, further comprising: The following steps are involved: The second surface of the sheet is placed in contact with the support surface of the tooling support.

3. The method according to claim 1 or 2, further comprising: The following steps are involved: releasing vacuum from the porous material of the tooling support; after releasing the vacuum, removing the sheet having features created by the machining operation from the machining support; drawing a vacuum across the porous material to hold the second sheet against the support surface; as well as The machining operation is performed on the second sheet while maintaining a vacuum within the porous material.

4. The method according to claim 3, in, Performing the machining operation includes machining indentations into the support surface of the machining support as features are created into the sheet, and the method further includes the steps of: A sealing material is applied within each of the indentations in the support surface prior to drawing the vacuum across the porous material to hold the second sheet against the support surface.

5. The method according to claim 1 or 2, further comprising: The following steps are involved: The vacuum provided to the porous material is adjusted to maintain a pressure differential across the second surface of the sheet material to hold the second surface against the support surface of the porous material while performing the machining operation on the sheet material.

6. The method according to claim 1 or 2, in, Performing the machining operation through the first surface includes drilling a hole through the sheet.

7. A processing support configured to reduce springback of a sheet material after a processing operation on the sheet material, the processing support include: a porous material having a plurality of surfaces, the plurality of surfaces including a support surface having a contour configured to contact and support the sheet; a sealing material covering each of the plurality of surfaces except the support surface; a vacuum port configured to provide a vacuum to the porous material; indentations in the support surface, the indentations corresponding to locations where processing operations are performed on the sheet; as well as Sealing material in each indentation.

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