Core bolts, fastener systems and methods for joining multiple substrates of workpieces having working and blind sides

Abstract

To provide a core bolt of a fastener system for joining multiple substrates of a workpiece with a working side and a blind side.SOLUTION: The core bolt includes a head portion, a shank portion, and a frangible drive element. The head portion includes a recessed torquing feature. The shank portion opposes the recessed torquing feature, and extends from the head portion along a longitudinal axis to a distal end. The shank portion includes a threaded portion between the distal end and the head portion. The frangible drive element extends from recessed torquing feature, and protrudes outward along the longitudinal axis to define a proximal end. A fastener system for joining multiple substrates of the workpiece includes a nut member and the core bolt. Methods for joining multiple substrates of a workpiece with a working side and a blind side are also provided.SELECTED DRAWING: Figure 1A

Description

[Technical Field]

[0001]

[0001] The present disclosure relates generally to blind fastener systems, and more particularly to core bolts and methods for such systems for joining multiple substrates of a workpiece having a working surface and a back surface. [Background technology]

[0002]

[0002] Future airplane wing box architectures will become smaller, resulting in limited space and the need for various fastening systems (e.g., skin / shear ties and skin / spars) that allow assembly from the wing's outer mold line. Traditional fastener styles with external wrench features require a torque wrench for installation and break off flush with the fastener head. Furthermore, these fasteners cannot be removed after installation without drilling a hole through the fastener head.

[0003]

[0003] Accordingly, those skilled in the art continue to conduct research and development efforts to improve single-sided fastener systems for joining multiple substrates. Summary of the Invention

[0004]

[0004] Disclosed are multiple embodiments of a core bolt, fastener system, and method for joining multiple substrates of a workpiece having a working surface and a back surface. The following are non-limiting examples of inventive subject matter according to the present disclosure, which may or may not be claimed.

[0005]

[0005] In one embodiment, a core bolt of a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface is disclosed. The disclosed core bolt includes a head portion, a shank portion, and a frangible drive element. The head portion includes a recessed torque feature. The shank portion extends axially from the head portion along a central longitudinal axis to a distal end of the core bolt. The shank portion includes a threaded portion between the distal end and the head portion. The frangible drive element extends from the recessed torque feature of the head portion and protrudes outward along the central longitudinal axis to define a proximal end of the core bolt.

[0006]

[0006] In one embodiment, a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface is disclosed. The disclosed fastener system includes a nut member and a core bolt. The nut member includes a nut bore having an internal thread. The core bolt includes a head portion, a shank portion, and a frangible drive element. The head portion includes a recessed torque feature. The shank portion extends axially from the head portion along a central longitudinal axis to a distal end of the core bolt. The shank portion includes a threaded portion between the distal end and the head portion. The frangible drive element extends from the head portion and protrudes outward along the central longitudinal axis to define a proximal end of the core bolt.

[0007] In one embodiment, a method for joining multiple substrates of a workpiece having a working surface and a back surface is disclosed. The disclosed method includes: (i) securing a nut member across mating bores extending through a plurality of substrates on a back surface of a workpiece, the nut member including a nut bore having an internal thread; (ii) inserting a core bolt from a work surface of the workpiece into the mating bore until a distal end of the core bolt contacts the nut member, the core bolt including a head portion having a recessed torque feature and a shank portion extending axially from the head portion along a central longitudinal axis to a distal end of the core bolt, the shank portion including a threaded portion between the distal end and the head portion, the core bolt also including a frangible drive element extending from the head portion and protruding outward along the central longitudinal axis to define a proximal end of the core bolt; (iv) rotating the core bolt to threadably engage the threaded portion with the internal threads of the nut member; and (v) further rotating the core bolt for further threaded engagement with the nut member until the frangible drive element disengages from the core bolt to achieve installation.

[0008]

[0008] Other embodiments of the disclosed core bolt, fastener system, and method for joining multiple substrates of a workpiece having a working surface and a back surface will become apparent from the following detailed description, the accompanying drawings, and the appended claims. [Brief explanation of the drawings]

[0009] [Figure 1A]

[0009] A side view of one embodiment of a core bolt for a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface. [Figure 1B]

[0010] FIG. 1B is a top view of the core bolt of FIG. 1A. [Figure 1C]

[0011] FIG. 1B is a close-up view of one embodiment of the interface between the frangible drive element and the head portion of the core bolt of FIG. 1A. [Figure 2A]

[0012] FIG. 1B is a side view of the core bolt of FIG. 1A after the frangible drive element has separated from the core head. [Figure 2B]

[0013] FIG. 1B is a top view of the core bolt of FIG. 1A after separation of the frangible drive element. [Figure 2C]

[0014] 1B is a side view of one embodiment of the frangible drive element of FIG. 1A after separation from the head portion. FIG. [Figure 3A]

[0015] FIG. 10 is a side view of another embodiment of a core bolt for a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface. [Figure 3B]

[0016] FIG. 10 is a side view of yet another embodiment of a core bolt for a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface. [Figure 4A]

[0017] FIG. 10 is a side view of yet another embodiment of a core bolt for a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface. [Figure 4B]

[0018] FIG. 4B is a top view of the core bolt of FIG. 4A. [Figure 5A]

[0019] FIG. 4B is a side view of the core bolt of FIG. 4A after the frangible drive element has separated from the core head. [Figure 5B]

[0020] FIG. 4B is a top view of the core bolt of FIG. 4A showing the core head after separation of the frangible drive element. [Figure 5C]

[0021] 4B is a side view of one embodiment of the frangible drive element of FIG. 4A after separation from the head portion. FIG. [Figure 6]

[0022] 1 is a cross-sectional side view of one embodiment of a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface. FIG. [Figure 7A]

[0023] 1 is a cross-sectional side view of an embodiment of a mating bore through multiple substrates of a workpiece having a countersink in the work surface. FIG. [Figure 7B]

[0024] FIG. 10 is a cross-sectional side view of another embodiment of a mating bore through multiple substrates of a workpiece having a counterbore in a working surface. [Figure 7C]

[0025] FIG. 10 is a cross-sectional side view of yet another embodiment of a mating bore extending through multiple substrates of a workpiece. [Figure 8]

[0026] FIG. 10 is a cross-sectional side view of another embodiment of a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface. [Figure 9]

[0027] FIG. 1 is a flow diagram of one embodiment of a method for joining multiple substrates of a workpiece having a working surface and a back surface. [Figure 10]

[0028] FIG. 10 is a flow diagram of an embodiment for fixing the nut member of FIG. 9. [Figure 11]

[0029] 10 is a flow diagram of several embodiments of the rotation and further rotation of the core bolt of FIG. 9. [Figure 12]

[0030] 10 is a flow diagram of several further examples of rotation and further rotation of the core bolt of FIG. 9. [Figure 13]

[0031] 10 is a flow diagram of yet further embodiments of the rotation and further rotation of the core bolt of FIG. 9. [Figure 14]

[0032] 10 is a flow diagram of another embodiment of a method for joining multiple substrates of a workpiece having a working surface and a back surface in combination with FIG. 9; [Figure 15]

[0033] 10 is a flow diagram of yet another embodiment of a method for joining multiple substrates of a workpiece having a working surface and a back surface, in combination with FIG. 9; [Figure 16]

[0034] FIG. 1 is a block diagram of an aircraft manufacturing and service method that implements one or more embodiments of the methods for joining substrates of a workpiece having a working surface and a back surface disclosed herein. [Figure 17]

[0035] FIG. 1 is a schematic diagram of an aircraft incorporating a workpiece having multiple substrates joined using one or more of the multiple embodiments of the core bolt assembly, blind fastener system, and method for joining multiple substrates of a workpiece having a working surface and a back surface disclosed herein. DETAILED DESCRIPTION OF THE INVENTION

[0010]

[0036] Various embodiments of the core bolt, fastener system, and method for joining multiple substrates of a workpiece having a working surface and a backside disclosed herein provide a fastener with a recessed head and a frangible drive element (that breaks off flush with the fastener head). This allows the fastener to be manually removed with a torque wrench, allowing for a one-sided removable bolt. The present disclosure is directed to a fastening system that combines a torque-breaking external wrench / drive element with a broached (head-side) recess in the same fastener. The external drive feature protrudes outward from the recess and breaks off flush with (or below) the top of the fastener after initial installation. This allows the recess to be used to remove the fastener after the drive feature is removed.

[0011]

[0037] No flush grinding is required after installation. The external wrench / drive element feature allows automation to install the fastener without having a calibrated torque tool. The broached (head-side) recess allows the fastener to be removed after installation for rework or repair.

[0012]

[0038] Various embodiments of the core bolt have an external drive element that allows the fastener to be torqued a predetermined amount. The external drive element breaks off when the predetermined torque is achieved. Various embodiments of the core bolt also incorporate a broached recess so that the fastener can be removed after installation.

[0013]

[0039] Various embodiments of the disclosed core bolt, fastener system, and method for joining multiple substrates in a workpiece having a working surface and a back surface incorporate a broach drive element and an external wrench feature that breaks off at a desired load. This combines the benefits of both types of features within the same fastener. These features alone have certain drawbacks. For example, a broached recessed fastener style requires a torque wrench for installation. On the other hand, an external wrench feature that shears / breaks off at a predetermined load leaves a bolt that can be easily removed after installation. For example, the retained bolt must be turned and pulled out or the head must be stripped off.

[0014]

[0040] Referring generally to FIGS. 1A-1C, 2A-2C, 3A-3B, 4A-4B, 6, and 7A-7C, by way of example, the present disclosure is directed to core bolts 100, 400 of fastener systems 600, 800 for joining multiple substrates 602 of a workpiece 604 having a working surface 606 and a back surface 608. FIG. 1A illustrates one embodiment of a core bolt for a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface. FIG. 1B illustrates a top view of the core bolt of FIG. 1A. FIG. 1C illustrates one embodiment of an interface between a frangible drive element and a head portion of the core bolt of FIG. 1A. FIG. 2A illustrates a side view of the core bolt of FIG. 1A after the frangible drive element has separated from the core head. FIG. 2B illustrates a top view of the core bolt of FIG. 1A after separation of the frangible drive element. FIG. 2C shows an embodiment of the frangible drive element of FIG. 1A after separation from the head portion. FIG. 3A shows another embodiment of a core bolt for a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface. FIG. 3B shows yet another embodiment of a core bolt for a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface. FIG. 4A shows yet another embodiment of a core bolt for a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface. FIG. 4B shows a top view of the core bolt of FIG. 4A. FIG. 6 shows an embodiment of a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface. FIG. 7A shows an embodiment of a mating bore extending through multiple substrates of a workpiece having a countersink on the working surface. FIG. 7B shows another embodiment of a mating bore extending through multiple substrates of a workpiece having a counterbore on the working surface. FIG. 7C shows yet another embodiment of a mating bore extending through multiple substrates of a workpiece.

[0015]

[0041] 1A-1C, 2A-2C, 3A-3B, 4A-4B, 6, and 7A-7C, in one or more embodiments, a core bolt 100, 400 of a fastener system 600, 800 for joining multiple substrates 602 of a workpiece 604 having a working surface 606 and a back surface 608 is disclosed. The core bolt includes a head portion 106, a shank portion 108, and a frangible drive element 112, 412. The head portion 106 includes a recessed torque feature 202. The shank portion 108 extends axially from the head portion 106 along a central longitudinal axis 110 to a distal end 104 of the core bolt 100, 400. The shank portion 108 includes a threaded portion 102 between the distal end 104 and the head portion 106. The frangible drive element 112 , 412 extends from the recessed torque feature 202 in the head portion 106 and projects outwardly along the central longitudinal axis 110 to define the proximal end 114 of the core bolt 100 , 400 .

[0016]

[0042] In another embodiment of the core bolt 100, 400, the core bolt 100, 400 comprises a metallic material. In a further embodiment, the metallic material comprises stainless steel, titanium, a titanium alloy, a cobalt-chromium alloy, a nickel-titanium alloy, or any other suitable metallic material in any suitable combination. In yet another embodiment of the core bolt 100, 400, the head portion 106 comprises a flush head, a countersunk head, a protruding head, a raised head, or any other suitable type of head in any suitable combination. In yet another embodiment of the core bolt 100, 400, the recessed torque feature 202 of the head portion 106 comprises a recessed offset cross drive feature, a recessed dovetail drive feature, a recessed cross tip drive feature, a recessed hex key drive feature, a recessed flat tip drive feature, or any other suitable type of recessed torque feature in any suitable combination.

[0017]

[0043] In yet another embodiment of the core bolt 100, 400, the recessed torque feature 202 on the head portion 106 facilitates rotation of the core bolt 100, 400 using an offset cruciform drive torque tool, a dovetail drive torque tool, a cross tip drive torque tool, a hex key drive torque tool, a flat tip drive torque tool, or any other suitable tool in any suitable combination after the frangible drive element 112, 412 separates from the head portion 106. In another embodiment of the core bolt 100, 400, the shank portion 108 is opposite the recessed torque feature 202 on the head portion 106. In yet another embodiment of the core bolt 100, 400, the shank portion 108 comprises a cylindrical body 302, a frusto-conical body 304, or any other suitable shaped body in any suitable combination. In yet another embodiment of the core bolt 100, 400, the frangible drive element 112, 412 extends from the head portion 106 at the central base area 116 of the recessed torque feature 202 and is configured to be engaged by a tool for installation of the core bolt 100, 400. In a further embodiment, the tool includes an end effector on a robotic arm, a gripping power tool, a hand tool, or any other suitable tool in any suitable combination.

[0018]

[0044] In another further embodiment, during installation of the core bolt 100, 400, the frangible drive element 112, 412 is separable from the head portion 106 at the central base area 116 of the recessed torque feature 202 in response to a predetermined torque being applied by a tool. In yet a further embodiment, the predetermined torque is based at least in part on the diameter of the core bolt 100, 400, the finish on the internal threads 614 of the nut member 610 into which the core bolt 100, 400 is installed, the level of friction on the internal threads 614 of the nut member 610, the level of friction between the shank portion 108 of the core bolt 100, 400 and the interface bore 702 extending through the plurality of substrates 602 into which the core bolt 100, 400 is installed, the level of friction between the shank portion 108 of the core bolt 100, 400 and the sleeve member 802 into which the core bolt 100, 400 is inserted, the effect of lubrication on the friction experienced by the core bolt 100, 400 during installation, the preload in the core bolt 100, 400 at the proximal end 114 of the frangible drive element 112, 412, or any other suitable characteristic of the fastener system in any suitable combination.

[0019]

[0045] In yet another embodiment of the core bolt 100, 400, the frangible drive element 112, 412 includes an interface portion 118, 418, a torque portion 120, 420, and a stem portion 124, 424. The interface portion 118, 418 extends and protrudes outward from the head portion 106. The torque portion 120, 420 includes a rotation feature 122, 422 at the proximal end 114 of the core bolt 100, 400. The stem portion 124, 424 extends axially between the interface portion 118, 418 and the torque portion 120, 420 along the central longitudinal axis 110 of the core bolt 100, 400. In a further embodiment, the interface portion 118, 418 of the frangible drive element 112, 412 extends from the head portion 106 at the central base area 116 of the recessed torque feature 202.

[0020]

[0046] In another further embodiment, the rotation features 122, 422 of the torque portion 120, 420 include a recessed spline drive feature, a recessed star drive feature, a recessed square lobe star drive feature, a recessed six-point star drive feature, a recessed six-point square lobe star drive feature, an opposed flat face head feature, a recessed hex key drive feature, a hex head feature, a recessed cross tip drive feature, a recessed flat tip drive feature, or any other suitable rotation feature in any suitable combination. In yet another further embodiment, the rotation features 122, 422 of the torque portion 120, 420 facilitate rotation of the core bolt 100, 400 using a spline drive torque tool, a star drive torque tool, a square lobe star drive torque tool, a six-point star drive torque tool, a six-point square lobe star drive torque tool, an opposed flat face socket torque tool, a hex key torque tool, a hex socket torque tool, a cross tip drive torque tool, a flat tip drive torque tool, or any other suitable tool in any suitable combination.

[0021]

[0047] In yet another further embodiment, the stem portion 124, 424 is opposite the rotation feature 122, 422 of the torque portion 120, 420. In yet another further embodiment, the stem portion 124, 424 comprises an elongated cylindrical shape, an elongated hexagonal shape, an elongated shape with multiple facets, or any other suitable shape in any suitable combination. In another further embodiment of the frangible drive element 112, 412, the interface portion 118, 418 defines a break-neck groove 126 located adjacent to the head portion 106 in the central base area 116 of the recessed torque feature 202 to facilitate separation of the frangible drive element 112, 412 from the core bolt 100, 400 in response to a predetermined torque being applied to the torque portion 120, 420 during installation of the core bolt 100, 400.

[0022]

[0048] In yet another embodiment of the frangible drive element 112, 412, the interface portion 118, 418 includes an interface body 204 that tapers from the stem portion 124, 424 to the head portion 106 at the central base area 116 of the recessed torque feature 202 to facilitate separation of the frangible drive element 112, 412 from the core bolt 100, 400 in response to a predetermined torque being applied to the torque portion 120, 420 during installation of the core bolt 100, 400. In yet a further embodiment of the frangible drive element 112, 412, the interface body 204 defines a break-neck groove 126 located adjacent the head portion 106 in the central base area 116 of the recessed torque feature 202 to further facilitate separation of the frangible drive element 112, 412 from the core bolt 100, 400 in response to a predetermined torque being applied to the torque portion 120, 420 during installation of the core bolt 100, 400.

[0023]

[0049] Referring generally to Figures 1A-1C, 2A-2C, 3A-3B, 4A-4B, 6, 7A-7C, and 8, by way of example, the present disclosure is directed to fastener systems 600, 800 for joining multiple substrates 602 of a workpiece 604 having a working surface 606 and a back surface 608. Figure 1A shows one embodiment of a core bolt for a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface. Figure 1B shows a top view of the core bolt of Figure 1A. Figure 1C shows one embodiment of an interface between a frangible drive element and a head portion of the core bolt of Figure 1A. Figure 2A shows a side view of the core bolt of Figure 1A after the frangible drive element has separated from the core head. Figure 2B shows a top view of the core bolt of Figure 1A after separation of the frangible drive element. FIG. 2C shows an embodiment of the frangible drive element of FIG. 1A after separation from the head portion. FIG. 3A shows another embodiment of a core bolt for a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface. FIG. 3B shows yet another embodiment of a core bolt for a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface. FIG. 4A shows yet another embodiment of a core bolt for a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface. FIG. 4B shows a top view of the core bolt of FIG. 4A. FIG. 6 shows an embodiment of a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface. FIG. 7A shows an embodiment of a mating bore extending through multiple substrates of a workpiece having a countersink on the working surface. FIG. 7B shows another embodiment of a mating bore extending through multiple substrates of a workpiece having a counterbore on the working surface. FIG. 7C shows yet another embodiment of a mating bore extending through multiple substrates of a workpiece. FIG. 8 illustrates another embodiment of a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface.

[0024]

[0050] 1A-1C, 2A-2C, 3A-3B, 4A-4B, 6, 7A-7C, and 8, in one or more embodiments, a fastener system 600, 800 is disclosed for joining multiple substrates 602 of a workpiece 604 having a working surface 606 and a back surface 608. The fastener system includes a nut member 610 and a core bolt 100, 400. The nut member 610 includes a nut bore 612 having an internal thread 614. The core bolt 100, 400 includes a head portion 106, a shank portion 108, and a frangible drive element 112, 412. The head portion 106 includes a recessed torque feature 202. The shank portion 108 extends axially from the head portion 106 along a central longitudinal axis 110 to a distal end 104 of the core bolt 100, 400. The shank portion 108 includes a threaded portion 102 between the distal end 104 and the head portion 106. A frangible drive element 112, 412 extends from the head portion 106 and projects outwardly along the central longitudinal axis 110 to define a proximal end 114 of the core bolt 100, 400. In another embodiment of the fastener system 600, 800, the plurality of substrates 602 includes at least one composite substrate. In yet another embodiment of the fastener system 600, 800, a mating bore 702 extending through the plurality of substrates 602 at the working surface 606 of the workpiece 604 includes a countersink portion 704, a counterbore portion 706, a cylindrical portion 708, or any other suitably shaped portion in any suitable combination.

[0025]

[0051] In yet another embodiment of the fastener system 600, 800, the nut member 610 is configured to position the nut bore 612 over the mating bore 702 that penetrates the plurality of substrates 602 on the back surface 608 of the workpiece 604. In yet another embodiment of the fastener system 600, 800, the nut member 610 is configured to be secured to the back surface 608 of the workpiece 604. In a further embodiment, the nut member 610 is configured to be secured using mechanical fasteners, a nut plate, a swage retention mechanism, an adhesive to bond materials, a gang channel, or any other suitable fastening technique in any suitable combination. In another embodiment of the fastener system 600, 800, the core bolt 100, 400 is configured to be inserted from the work surface 606 of the workpiece 604 into the mating bore 702 that penetrates the plurality of substrates 602. In yet another embodiment of the fastener system 600 , 800 , the threaded portion 102 of the shank portion 108 of the core bolt 100 , 400 is configured to threadably engage the internal threads 614 of the nut member 610 .

[0026]

[0052] In yet another embodiment of the fastener system 600, 800, the head portion 106 of the core bolt 100, 400 includes a flush head, a countersunk head, a protruding head, a raised head, or any other suitable type of head in any suitable combination.

[0027]

[0053] In yet another embodiment of the fastener system 600, 800, the recessed torque feature 202 on the head portion 106 of the core bolt 100, 400 comprises a recessed offset cross drive feature, a recessed dovetail drive feature, a recessed cross tip drive feature, a recessed hex key drive feature, a recessed flat tip drive feature, or any other suitable type of recessed torque feature in any suitable combination. In yet another embodiment of the fastener system 600, 800, after the frangible drive element 112, 412 of the core bolt 100, 400 separates from the head portion 106, the recessed torque feature 202 on the head portion 106 facilitates rotation of the core bolt 100, 400 using an offset cross drive torque tool, a dovetail drive torque tool, a cross tip drive torque tool, a hex key drive torque tool, a flat tip drive torque tool, or any other suitable tool in any suitable combination.

[0028]

[0054] In yet another embodiment of the fastener system 600, 800, the shank portion 108 of the core bolt 100, 400 is opposite the recessed torque feature 202 of the head portion 106. In yet another embodiment of the fastener system 600, 800, the shank portion 108 of the core bolt 100, 400 includes a cylindrical body 302, a frustoconical body 304, or any other suitable shaped body in any suitable combination.

[0029]

[0055] In yet another embodiment of the fastener system 600, 800, the frangible drive element 112, 412 of the core bolt 100, 400 extends from the head portion 106 at the central base area 116 of the recessed torque feature 202 and is configured to be engaged by a tool for installation of the core bolt 100, 400. In a further embodiment, the tool includes an end effector on a robotic arm, a gripping power tool, a hand tool, or any other suitable tool in any suitable combination. In another further embodiment, the frangible drive element 112, 412 is separable from the head portion 106 at the central base area 116 of the recessed torque feature 202 in response to a predetermined torque being applied by the tool during installation of the core bolt 100, 400. In yet another embodiment of the fastener system 600, 800, the frangible drive element 112, 412 of the core bolt 100, 400 includes an interface portion 118, 418, a torque portion 120, 420, and a stem portion 124, 424. The interface portion 118, 418 extends and projects outward from the head portion 106. The torque portion 120, 420 includes a rotation feature 122, 422 at the proximal end 114 of the core bolt 100, 400. The stem portion 124, 424 extends axially along the central longitudinal axis 110 of the core bolt 100, 400 between the interface portion 118, 418 and the torque portion 120, 420.

[0030]

[0056] In a further embodiment, the interface portion 118, 418 of the frangible drive element 112, 412 extends from the head portion 106 at the central base area 116 of the recessed torque feature 202. In another further embodiment, the rotational feature 122, 422 of the torque portion 120, 420 comprises a recessed spline drive feature, a recessed star drive feature, a recessed square lobe star drive feature, a recessed six point star drive feature, a recessed six point square lobe star drive feature, an opposed flat face head feature, a recessed hex key drive feature, a hex head feature, a recessed cross tip drive feature, a recessed flat tip drive feature, or any other suitable rotational feature in any suitable combination.

[0031]

[0057] In yet another further embodiment, the rotation feature 122, 422 of the torque portion 120, 420 facilitates rotation of the core bolt 100, 400 using a spline drive torque tool, a star drive torque tool, a square lobe star drive torque tool, a six-point star drive torque tool, a six-point square lobe star drive torque tool, an opposed flat-faced socket torque tool, a hex key torque tool, a hex socket torque tool, a cross-tip drive torque tool, a flat-tip drive torque tool, or any other suitable tool in any suitable combination. In yet another further embodiment, the stem portion 124, 424 of the frangible drive element 112, 412 is opposite the rotation feature 122, 422 of the torque portion 120, 420. In yet another further embodiment, the stem portion 124, 424 of the frangible drive element 112, 412 comprises an elongated cylindrical shape, an elongated hexagonal shape, an elongated shape with multiple facets, or any other suitable shape in any suitable combination.

[0032]

[0058] In another further embodiment of the fastener system 600, 800, the interface portion 118, 418 of the frangible drive element 112, 412 defines a break-neck groove 126 located adjacent to the head portion 106 in the central base area 116 of the recessed torque feature 202 to facilitate separation of the frangible drive element 112, 412 from the core bolt 100, 400 in response to a predetermined torque being applied to the torque portion 120, 420 during installation of the core bolt 100, 400. In another further embodiment of the fastener system 600, 800, the interface portion 118, 418 of the frangible drive element 112, 412 includes an interface body 204 that tapers from the stem portion 124, 424 to the head portion 106 at the central base area 116 of the recessed torque feature 202 to facilitate separation of the frangible drive element 112, 412 from the core bolt 100, 400 in response to a predetermined torque being applied to the torque portion 120, 420 during installation of the core bolt 100, 400. In yet a further embodiment of the fastener system 600, 800, the interface body 204 defines a break-neck groove 126 located adjacent the head portion 106 in the central base area 116 of the recessed torque feature 202 to further facilitate separation of the frangible drive element 112, 412 from the core bolt 100, 400 in response to a predetermined torque being applied to the torque portion 120, 420 during installation of the core bolt 100, 400.

[0033]

[0059] In yet another embodiment, the fastener system 600, 800 also includes a sleeve member 802 having an outer sleeve surface 804 with a lubricious coating. The sleeve member 802 is configured to be inserted into a mating bore 702 that extends through the plurality of substrates 602 from the working surface 606 of the workpiece 604. The core bolt 100, 400 is configured to be inserted into the central bore 806 of the sleeve member 802. In a further embodiment, the lubricious coating on the outer sleeve surface 804 of the sleeve member 802 includes conductive features configured to provide electromagnetic energy protection to the workpiece 604. In another further embodiment, the outer sleeve surface 804 of the sleeve member 802 is coated with a conductive coating to provide electromagnetic energy protection to the workpiece 604.

[0034]

[0060] In yet another further embodiment of the fastener system 600, 800, the sleeve member 802 also includes an inner sleeve surface 808, and the shank portion 108 of the core bolt 100, 400 includes an outer shank surface 810. At least one of the inner sleeve surface 808 and the outer shank surface 810 is coated with a lubricious coating. In yet another further embodiment of the fastener system 600, 800, the sleeve member 802 also includes an elongated sleeve body 812 that defines a central bore 806. The elongated sleeve body 812 includes an outer sleeve surface 804, an inner sleeve surface 808 facing the central bore 806, a first end 814 associated with the working surface 606 of the workpiece 604, and a second end 816 associated with the back surface 608 of the workpiece 604. At least the inner sleeve surface 808 tapers from a larger inner sleeve diameter adjacent the first end 814 to a smaller inner sleeve diameter adjacent the second end 816. The central bore 806 thereby comprises a frusto-conical sleeve bore 818. In yet a further embodiment, the outer sleeve surface 804 of the sleeve member 802 is cylindrical. The elongated sleeve body 812 thereby comprises a cylindrical sleeve body 820 having a frusto-conical sleeve bore 818.

[0035]

[0061] In yet another further embodiment, when the core bolt 100, 400 is fully threaded onto the nut member 610, the shank portion 108 of the core bolt 100, 400 is configured to cause radial expansion of the sleeve member 802, and the sleeve member 802 is configured to provide an interference fit within the mating bore 702 that penetrates the multiple substrates 602.

[0036]

[0062] In another embodiment, the fastener system 600, 800 also includes a thermoplastic polymer sealant 616 disposed within a cavity 822 between the nut member 610 and the backside 608 of the workpiece 604. In a further embodiment, the thermoplastic polymer sealant 616 provides electromagnetic energy protection to the workpiece 604.

[0037]

[0063] In yet another embodiment, the fastener system 600, 800 also includes a cap sealant member 618 having a dome and configured to be disposed over the nut member 610 on the back surface 608 of the workpiece 604. In a further embodiment, the cap sealant member 618 provides electromagnetic energy protection to the workpiece 604.

[0038]

[0064] Referring generally to FIGS. 1A-1C, 2A-2C, 3A-3B, 4A-4B, 6, 7A-7C, and 8-15, by way of example, the present disclosure is directed to methods 900, 1400, 1500 for joining multiple substrates 602 of a workpiece 604 having a working surface 606 and a back surface 608. FIG. 1A illustrates an example of a core bolt for a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface. FIG. 1B illustrates a top view of the core bolt of FIG. 1A. FIG. 1C illustrates an example of an interface between a frangible drive element and a head portion of the core bolt of FIG. 1A. FIG. 2A illustrates a side view of the core bolt of FIG. 1A after the frangible drive element has separated from the core head. FIG. 2B illustrates a top view of the core bolt of FIG. 1A after separation of the frangible drive element. Figure 2C shows an embodiment of the frangible drive element of Figure 1A after separation from the head portion. Figure 3A shows another embodiment of a core bolt for a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface. Figure 3B shows yet another embodiment of a core bolt for a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface. Figure 4A shows yet another embodiment of a core bolt for a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface. Figure 4B shows a top view of the core bolt of Figure 4A. Figure 6 shows an embodiment of a fastener system for joining multiple substrates of a workpiece having a working surface and a back surface.

[0039]

[0065] FIG. 7A illustrates one embodiment of a mating bore extending through multiple substrates of a workpiece having a countersink on the work surface. FIG. 7B illustrates another embodiment of a mating bore extending through multiple substrates of a workpiece having a counterbore on the work surface. FIG. 7C illustrates yet another embodiment of a mating bore extending through multiple substrates of a workpiece. FIG. 8 illustrates another embodiment of a fastener system for joining multiple substrates of a workpiece having a work surface and a back surface. FIG. 9 provides a method 900 for joining multiple substrates 602 of a workpiece 604 having a work surface 606 and a back surface 608. FIG. 10 provides an embodiment of securing 902 the nut member 610 of FIG. 9. FIG. 11 provides several embodiments of rotating 906 the core bolt 100, 400 of FIG. 9 and further rotating 908 the core bolt 100, 400. Figure 12 provides several further examples of rotating 906 the core bolts 100, 400 and further rotating 908 the core bolts 100, 400 of Figure 9. Figure 13 provides several further examples of rotating 906 the core bolts 100, 400 and further rotating 908 the core bolts 100, 400 of Figure 9. Figure 14, in combination with Figure 9, provides one embodiment of a method 1400 for joining multiple substrates 602 of a workpiece 604 having a working surface 606 and a back surface 608. Figure 15, in combination with Figure 9, provides a method 1500 for joining multiple substrates 602 of a workpiece 604 having a working surface 606 and a back surface 608.

[0040]

[0066] 1A-1C, 2A-2C, 3A-3B, 4A-4B, 6, 7A-7C, and 8-15, in one or more embodiments, a method 900 (see FIG. 9) for joining multiple substrates 602 of a workpiece 604 having a working surface 606 and a back surface 608 includes securing 902 a nut member 610 over a mating bore 702 that extends through the multiple substrates 602 on the back surface 608 of the workpiece 604. The nut member 610 includes a nut bore 612 having an internal thread 614. At 904, the core bolt 100, 400 is inserted into the mating bore 702 from the working surface 606 of the workpiece 604 until the distal end 104 of the core bolt 100, 400 contacts the nut member 610. The core bolt 100, 400 includes a head portion 106 having a recessed torque feature 202 and a shank portion 108 extending axially from the head portion 106 along a central longitudinal axis 110 to a distal end 104 of the core bolt 100, 400. The shank portion 108 includes a threaded portion 102 between the distal end 104 and the head portion 106. The core bolt 100, 400 also includes a frangible drive element 112, 412 extending from the head portion 106 and projecting outwardly along the central longitudinal axis 110 to define a proximal end 114 of the core bolt 100, 400. At 906, the core bolt 100, 400 is rotated to threadably engage the threaded portion 102 with the internal threads 614 of the nut member 610. At 908, the core bolt 100, 400 is further rotated for further threaded engagement with the nut member 610 until the frangible drive element 112, 412 separates from the core bolt 100, 400 to achieve installation.

[0041]

[0067] In another embodiment of the method 900, securing 902 the nut member 610 includes securing 1002 (see FIG. 10 ) the nut member 610 to the backside 608 of the workpiece 604 using mechanical fasteners, a nut plate, a swage retention mechanism, an adhesive to bond materials, a gang channel, or any other suitable fastening technique in any suitable combination. In yet another embodiment of the method 900, after the frangible drive element 112, 412 separates from the head portion 106, the recessed torque feature 202 in the head portion 106 facilitates rotation of the core bolt 100, 400 from the work surface 606 of the workpiece 604 for removal and subsequent replacement. In yet another embodiment of the method 900, the shank portion 108 of the core bolt 100, 400 includes a cylindrical body 302, a frusto-conical body 304, or any other suitable shaped body in any suitable combination.

[0042]

[0068] In yet another embodiment of the method 900, the frangible drive element 112, 412 of the core bolt 100, 400 extends from the head portion 106 at the central base area 116 of the recessed torque feature 202 and is configured to be engaged by a tool to at least one of rotating 906 and further rotating 908 the core bolt 100, 400. In a further embodiment, the tool includes an end effector on a robotic arm, a gripping power tool, a hand tool, or any other suitable tool in any suitable combination. In another further embodiment, during further rotating 908 the core bolt 100, 400, the frangible drive element 112, 412 disengages from the head portion 106 at the central base area 116 of the recessed torque feature 202 in response to a predetermined torque being applied by the tool.

[0043]

[0069] In another embodiment of the method 900, the frangible drive element 112, 412 of the core bolt 100, 400 includes an interface portion 118, 418, a torque portion 120, 420, and a stem portion 124, 424. The interface portion 118, 418 extends and projects outward from the head portion 106. The torque portion 120, 420 includes a rotation feature 122, 422 at the proximal end 114 of the core bolt 100, 400. The stem portion 124, 424 extends axially along the central longitudinal axis 110 of the core bolt 100, 400 between the interface portion 118, 418 and the torque portion 120, 420. The stem portion 124, 424 is opposite the rotation feature 122, 422 of the torque portion 120, 420. In a further embodiment, the interface portion 118 , 418 of the frangible drive element 112 , 412 extends from the head portion 106 at the central base area 116 of the recessed torque feature 202 .

[0044]

[0070] In another further embodiment of the method 900, rotating 906 and further rotating 908 the core bolt 100, 400 includes using a tool to engage 1102 (see FIG. 11 ) the rotation features 122, 422 of the torque portion 120, 420 of the frangible drive element 112, 412. At 1104, the tool is used to rotate the core bolt 100, 400 to threadably engage the threaded portion 102 of the shank portion 108 with the internal threads 614 of the nut member 610. At 1106, to achieve installation, the tool is used to further rotate the core bolt 100, 400 for further engagement with the nut member 610 until the interface portion 118, 418 breaks and the frangible drive element 112, 412 separates from the core bolt 100, 400.

[0045]

[0071] In yet another embodiment, the interface portion 118, 418 of the frangible drive element 112, 412 includes a break-neck groove 126 located adjacent the head portion 106 in the central base area 116 of the recessed torque feature 202. In this embodiment of the method 900, rotating 906 the core bolt 100, 400 and further rotating 908 the core bolt 100, 400 includes using a tool to engage 1202 (see FIG. 12 ) the rotation features 122, 422 of the torque portion 120, 420 of the frangible drive element 112, 412. At 1204, the tool is used to rotate the core bolt 100, 400 to threadably engage the threaded portion 102 of the shank portion 108 with the internal threads 614 of the nut member 610. At 1206, to achieve installation, a tool is used to further rotate the core bolt 100, 400 for further engagement with the nut member 610 until the interface portion 118, 418 breaks at the break neck groove 126 and the frangible drive element 112, 412 separates from the core bolt 100, 400.

[0046]

[0072] In yet another embodiment, the interface portion 118, 418 of the frangible drive element 112, 412 includes an interface body 204 that tapers from the stem portion 124, 424 to the head portion 106 at the central base area 116 of the recessed torque feature 202. In this embodiment of the method 900, rotating 906 the core bolt 100, 400 and further rotating 908 the core bolt 100, 400 includes using a tool to engage 1302 (see FIG. 13 ) the rotation features 122, 422 of the torque portion 120, 420 of the frangible drive element 112, 412. At 1304, the tool is used to rotate the core bolt 100, 400 to threadably engage the threaded portion 102 of the shank portion 108 with the internal threads 614 of the nut member 610. At 1306, to achieve installation, a tool is used to further rotate the core bolt 100, 400 for further threaded engagement with the nut member 610 until the interface body 204 breaks at the central base area 116 of the recessed torque feature 202 in the head portion 106 of the core bolt 100, 400 and the frangible drive element 112, 412 separates from the core bolt 100, 400.

[0047]

[0073] 1A-1C, 2A-2C, 3A-3B, 4A-4B, 6, 7A-7C, 8, 9, and 14, in one or more embodiments, a method 1400 (see FIG. 14) for joining multiple substrates 602 of a workpiece 604 having a working surface 606 and a back surface 608 includes method 900 of FIG. 9. Method 1400 continues from steps 902 to 1402, in which a sleeve member 802 is inserted into a joining bore 702 that extends from the working surface 606 of the workpiece 604 through the multiple substrates 602. The sleeve member 802 includes an outer sleeve surface 804 having a lubricious coating. In method 1400, inserting 904 the core bolt 100, 400 includes inserting 1404 the core bolt 100, 400 into a central bore 806 of the sleeve member 802.

[0048]

[0074] In another embodiment of the method 1400, rotating 906 the core bolt 100, 400 when the core bolt 100, 400 is fully threadedly engaged with the nut member 610 includes radially expanding 1406 the sleeve member 802 within the mating bore 702 extending through the plurality of substrates 602 when the core bolt 100, 400 is fully threadedly engaged with the nut member 610. In this embodiment, further rotating 908 the core bolt 100, 400 includes providing 1408 an interference fit with the sleeve member 802 within the mating bore 702 in response to the radial expansion of the sleeve member 802 when the core bolt 100, 400 is fully threadedly engaged with the nut member 610.

[0049]

[0075] 1A-1C , 6 , 8 , 9 , and 15 , in one or more embodiments, a method 1500 (see FIG. 15 ) for joining multiple substrates 602 of a workpiece 604 having a working surface 606 and a back surface 608 includes applying 1502 a thermoplastic polymer sealant 616 to a nut member 610, whereby the thermoplastic polymer sealant 616, in conjunction with securing 902 the nut member 610, at least partially fills the cavity 822 between the nut member 610 and the back surface 608 of the workpiece 604. The method 1500 continues from 1502 to 902. In another embodiment, the method 1500 continues from 902 to 1504, where a cap sealant member 618 is placed over the nut member 610 on the back surface 608 of the workpiece 604.

[0050]

[0076] Embodiments of the core bolt, fastener system, and method for joining substrates of a workpiece having a working surface and a back surface may be related to or used in the context of aircraft manufacturing. While an aerospace example is provided, the embodiments and principles disclosed herein may be applied to other products, such as in the automotive, space, construction, and other design and manufacturing industries. Thus, in addition to aircraft, the embodiments and principles disclosed herein may be applied to the use of composite products in the manufacture of various types of vehicles and the construction of various types of buildings.

[0051]

[0077] The foregoing detailed description refers to the accompanying drawings, which illustrate specific embodiments described by the present disclosure. Other embodiments having different structures and steps do not depart from the scope of the present disclosure. Like reference numerals may represent the same feature, element, or component in the various drawings. Throughout this disclosure, any of a plurality of items may be referred to individually as that item, and a plurality of items may be referred to collectively as items (plural) and may be represented by like reference numerals. Furthermore, as used herein, a feature, element, component, or step preceded by the term "a" or "an" should be understood not to exclude a plurality of features, elements, components, or steps, unless expressly stated to exclude it.

[0052]

[0078] Illustrative, non-exhaustive examples of the inventive subject matter according to the present disclosure may be, but are not necessarily, claimed. Reference herein to an "example" means that one or more features, structures, elements, components, properties, and / or operational steps described in connection with the example are included in at least one aspect, embodiment, and / or implementation of the subject matter according to the present disclosure. Thus, the phrases "one example," "another example," "one or more examples," and similar phrases used throughout this disclosure may, but do not necessarily, refer to the same example. Furthermore, subject matter characterizing any one of the examples may, but does not necessarily, include subject matter characterizing any other example. Furthermore, subject matter characterizing any one of the examples may, but does not necessarily, be combined with subject matter characterizing any other example.

[0053]

[0079] As used herein, a system, apparatus, device, structure, article, element, component, or hardware that is "configured to" perform a particular function is, in fact, capable of performing that particular function without any modification, rather than merely having the potential to perform that particular function after further modification. In other words, a system, apparatus, device, structure, article, element, component, or hardware that is "configured" to perform a particular function is specifically selected, created, implemented, utilized, programmed, and / or designed for the purpose of performing that particular function. As used herein, "configured to" refers to an existing characteristic of a system, apparatus, device, structure, article, element, component, or hardware that enables the system, apparatus, device, structure, article, element, component, or hardware to perform a particular function without further modification. For the purposes of this disclosure, a system, apparatus, device, structure, article, element, component, or hardware that is described as "configured" to perform a particular function may additionally or alternatively be described as "adapted" and / or "operating" to perform that function.

[0054]

[0080] Unless otherwise indicated, terms such as "first," "second," "third," etc. are used herein merely as designators and are not intended to impose any sequential, positional, or hierarchical requirements on the items to which they refer. Furthermore, a reference to, e.g., a "second" item does not require or preclude the presence of, e.g., a "first" or lower-numbered item and / or, e.g., a "third" or higher-numbered item.

[0055]

[0081] As used herein, the phrase "at least one of" used in conjunction with listed items means that various combinations of one or more of the listed items may be used, and that only one of each listed item may be required. For example, "at least one of item A, item B, and item C" may include, but is not limited to, "item A," or "item A and item B." This example may also include item A, item B, and item C, or item B and item C. In other examples, "at least one of" may be, for example, but is not limited to, "two item A, one item B, and ten item C," "four item B, and seven item C," and other suitable combinations. As used herein, the phrase "and / or" and the indicia " / " include any and all combinations of one or more of the associated listed items.

[0056]

[0082] As used herein, "coupled," "coupling," and similar terms refer to two or more elements that are coupled, connected, fastened, connected, in communication, or otherwise associated with one another (e.g., mechanically, electrically, fluidly, optically, electromagnetically). In various examples, these elements may be directly associated or indirectly associated. For example, element A may be directly associated with element B. As another example, element A may be associated with element B, e.g., through another element C. It should be understood that not all relationships between the various disclosed elements are necessarily depicted. Thus, other couplings may exist than those shown in the figures.

[0057]

[0083] As used herein, the term "approximately" refers to or describes a condition that is close to, but not exactly, a specified condition that still performs a desired function or achieves a desired result. As an example, the term "approximately" refers to a condition that is within an acceptable predetermined tolerance or precision, such as within 10% of the specified condition. However, the term "approximately" does not exclude a condition that is exactly the specified condition. As used herein, the term "substantially" refers to a condition that is essentially a specified condition that performs a desired function or achieves a desired result.

[0058]

[0084] The above-referenced Figures 1A-1C, 2A-2C, 3A-3B, 4A-4B, 6, 7A-7C, and 8 may depict functional elements, features, or components thereof and do not necessarily imply any particular structure. Accordingly, modifications, additions, and / or omissions may be made to the illustrated configurations. Furthermore, those skilled in the art will appreciate that not all elements, features, and / or components described and shown in the above-referenced Figures 1A-1C, 2A-2C, 3A-3B, 4A-4B, 6, 7A-7C, and 8 need be included in every embodiment, and not all elements, features, and / or components described herein are necessarily shown in each illustrative embodiment. Thus, some of the elements, features, and / or components described and shown in Figures 1A-1C, 2A-2C, 3A-3B, 4A-4B, 6, 7A-7C, and 8 can be combined in various ways without the need to include other features described and shown in Figures 1A-1C, 2A-2C, 3A-3B, 4A-4B, 6, 7A-7C, and 8, other figures, and / or the accompanying disclosure, although such combinations are not explicitly set forth herein. Similarly, additional features, not limited to the examples presented, may be combined with some or all of the features shown and described herein. Unless expressly stated otherwise, the above-referenced schematic diagrams of various embodiments in Figures 1A-1C, 2A-2C, 3A-3B, 4A-4B, 6, 7A-7C, and 8 are not intended to imply architectural limitations with respect to example embodiments. Rather, it is to be understood that while one example configuration is depicted, it may be modified as appropriate. Thus, modifications, additions, and / or omissions may be made to the illustrated configuration.Additionally, elements, features, and / or components that serve similar, or at least substantially similar, purposes are similarly numbered in each of Figures 1A-1C, 2A-2C, 3A-3B, 4A-4B, 6, 7A-7C, and 8, and such elements, features, and / or components may not be described in detail herein with respect to each of Figures 1A-1C, 2A-2C, 3A-3B, 4A-4B, 6, 7A-7C, and 8. Similarly, not all elements, features, and / or components are numbered in each of Figures 1A-1C, 2A-2C, 3A-3B, 4A-4B, 6, 7A-7C, and 8, but their associated reference numbers may be used consistently herein.

[0059]

[0085] In the above-referenced Figures 9-15, multiple blocks may represent operations, steps, and / or portions thereof, and the lines connecting various blocks do not imply any particular order or dependency of the operations or portions thereof. It should be understood that not all dependencies between the various disclosed operations are necessarily depicted. Figures 9-15 and the accompanying disclosure describing the steps of the disclosed methods described herein should not be construed as necessarily dictating the sequence in which the operations are performed. Rather, although one exemplary order is shown, it should be understood that the sequence of operations may be altered as needed. Accordingly, modifications, additions, and / or omissions may be made to the illustrated operations, and certain operations may be performed in a different order or simultaneously. Additionally, those skilled in the art will recognize that not all of the operations described need be performed.

[0060]

[0086] Furthermore, throughout this specification, references to features, advantages, or similar language as used herein do not imply that all of the features and advantages that may be realized in the examples disclosed herein should or are in any single example. Rather, language referring to features and advantages is understood to mean that the particular feature, advantage, or characteristic described in connection with an example is included in at least one example. Thus, descriptions of features, advantages, and similar language as used throughout this disclosure may, but do not necessarily, refer to the same single example.

[0061]

[0087] Examples of the subject matter disclosed herein may be described in the context of aircraft manufacturing and service method 1600 shown in FIG. 16 and aircraft 1700 shown in FIG. 17 . In one or more embodiments, the disclosed methods and systems for relating test data for a part under test to a final product coordinate system may be used in aircraft manufacturing. During pre-production, service method 1600 may include specification and design of aircraft 1700 (block 1602) and material procurement (block 1604). During production, component and subassembly manufacturing (block 1606) and system integration (block 1608) of aircraft 1700 may occur. Aircraft 1700 may then undergo certification and delivery (block 1610) and be placed into service (block 1612). During operation, aircraft 1700 may be scheduled for routine maintenance and service (block 1614). The routine maintenance and service may include modification, reconfiguration, refurbishment, etc. of one or more systems of aircraft 1700.

[0062]

[0088] Each of the processes of method 1600 may be performed or implemented by a system integrator, a third party, and / or an operator (e.g., a customer). For purposes of this specification, a system integrator may include, but is not limited to, any number of aircraft manufacturers and major system subcontractors, a third party may include, but is not limited to, any number of vendors, subcontractors, and suppliers, and an operator may be an airline, a leasing company, a military organization, a service organization, etc.

[0063]

[0089] 17 , an aircraft 1700 produced by maintenance method 1600 may include an airframe 1702 having multiple high-level systems 1704 and an interior 1706. Examples of high-level systems 1704 include one or more of a propulsion system 1708, an electrical system 1710, a hydraulic system 1712, and an environmental system 1714. Any number of other systems may be included. While an aerospace example is provided, the principles disclosed herein may also be applied to other industries, such as the automotive industry. As such, in addition to the aircraft 1700, the principles disclosed herein may also be applied to other vehicles, such as land vehicles, marine vehicles, space vehicles, etc.

[0064]

[0090] The disclosed systems and methods for relating test data for a part under test to a final product coordinate system may be employed during any one or more of multiple stages of manufacturing and service method 1600. For example, components or subassemblies corresponding to component and subassembly manufacturing (block 1606) may be fabricated or manufactured in a manner similar to components or subassemblies produced during the operation of aircraft 1700 (block 1612). Also, one or more embodiments of the system(s), method(s), or combinations thereof may be utilized during the manufacturing stage (blocks 1606 and 1608), for example, by substantially streamlining or reducing the cost of assembling aircraft 1700. Similarly, one or more embodiments implementing the system or method, or combinations thereof, may be utilized during the operation of aircraft 1700 (block 1612) and / or during maintenance and service (block 1614), by way of example and not limitation.

[0065]

[0091] The described features, advantages, and characteristics of one embodiment may be combined in any suitable manner in one or more other embodiments. Those skilled in the art will recognize that the embodiments described herein may be practiced without one or more of the specific features or advantages of a particular embodiment. In other cases, additional features and advantages may be recognized in certain embodiments that are not present in all embodiments. Furthermore, while various embodiments of the core bolt 100, 400, fastener system 600, 800, and method 900, 1400, 1500 for joining multiple substrates 602 of a workpiece 604 having a working surface 606 and a back surface 608 have been shown and described, numerous variations will occur to those skilled in the art upon reading the specification. The present application includes such variations and is limited only by the scope of the claims.

Claims

1. A core bolt (100, 400) for a fastener system (600, 800) for joining multiple substrates (602) of a workpiece (604) having a working surface (606) and a back surface (608), comprising: a head portion (106) with recessed torque features (202); a shank portion (108) extending axially from the head portion (106) along a central longitudinal axis (110) to a distal end (104) of the core bolt (100, 400), the shank portion (108) including a threaded portion (102) between the distal end (104) and the head portion (106); a core bolt including a frangible drive element (112, 412) extending from a recessed torque feature (202) in the head portion (106) and projecting outwardly along the central longitudinal axis (110) to define a proximal end (114) of the core bolt (100, 400).

2. The core bolt of claim 1 , wherein the core bolt (100, 400) comprises a metallic material.

3. The core bolt of claim 2 , wherein the metallic material comprises at least one of stainless steel, titanium, a titanium alloy, a cobalt chromium alloy, and a nickel titanium alloy.

4. The core bolt of claim 1 , wherein the head portion (106) comprises at least one of a flush head, a countersink head, a protruding head, and a raised head.

5. 2. The core bolt of claim 1, wherein the recessed torque feature (202) of the head portion (106) comprises at least one of a recessed offset cross drive feature, a recessed dovetail drive feature, a recessed cross tip drive feature, a recessed hex key drive feature, and a recessed flat tip drive feature.

6. 2. The core bolt of claim 1, wherein after the frangible drive element separates from the head portion, the recessed torque feature of the head portion facilitates rotation of the core bolt using at least one of an offset cross drive torque tool, a dovetail drive torque tool, a cross tip drive torque tool, a hex key drive torque tool, and a flat tip drive torque tool.

7. The core bolt of claim 1 , wherein the shank portion (108) is opposite the recessed torque feature (202) of the head portion (106).

8. The core bolt of claim 1, wherein the shank portion (108) comprises at least one of a cylindrical body (302) and a frusto-conical body (304).

9. 2. The core bolt of claim 1, wherein the frangible drive element extends from the head portion at a central base area of ​​the recessed torque feature and is configured to be engaged by a tool for installation of the core bolt.

10. The core bolt of claim 9 , wherein the tool comprises at least one of an end effector on a robotic arm, a gripping power tool, and a hand tool.

11. 10. The core bolt of claim 9, wherein the frangible drive element (112, 412) is separable from the head portion (106) at the central base area (116) of the recessed torque feature (202) in response to a predetermined torque being applied by the tool during installation of the core bolt (100, 400).

12. The predetermined torque is determined based on the diameter of the core bolt (100, 400), the finish on the internal threads (614) of the nut member (610) in which the core bolt (100, 400) is installed, the friction level of the internal threads (614) of the nut member (610), the friction level between the shank portion (108) of the core bolt (100, 400) and the mating bores (702) through the plurality of substrates (602) in which the core bolt (100, 400) is installed, 12. The core bolt of claim 11, wherein the friction between the shank portion of the core bolt and a sleeve member into which the core bolt is inserted is based at least in part on at least one of: a level of friction between the shank portion of the core bolt and a sleeve member into which the core bolt is inserted; an effect of lubrication on the friction experienced by the core bolt during installation; and a preload within the core bolt at the proximal end of the frangible drive element.

13. The frangible drive element (112, 412) an interface portion (118, 418) extending from said head portion (106) and projecting outward; a torque portion (120, 420) including a rotation feature (122, 422) at the proximal end (114) of the core bolt (100, 400); and 2. The core bolt of claim 1, further comprising a stem portion extending axially along the central longitudinal axis of the core bolt between the interface portion and the torque portion.

14. 14. The core bolt of claim 13, wherein the interface portion (118, 418) of the frangible drive element (112, 412) extends from the head portion (106) at a central base area (116) of the recessed torque feature (202).

15. 14. The core bolt of claim 13, wherein the rotation features (122, 422) of the torque portion (120, 420) include at least one of a recessed spline drive feature, a recessed star drive feature, a recessed square lobe star drive feature, a recessed six point star drive feature, a recessed six point square lobe star drive feature, an opposed flat face head feature, a recessed hex key drive feature, a hex head feature, a recessed cross tip drive feature, and a recessed flat tip drive feature.

16. 14. The core bolt of claim 13, wherein the rotation feature (122, 422) of the torque portion (120, 420) facilitates rotation of the core bolt (100, 400) using at least one of a spline drive torque tool, a star drive torque tool, a square lobe star drive torque tool, a six point star drive torque tool, a six point square lobe star drive torque tool, an opposed flat face socket torque tool, a hex key torque tool, a hex socket torque tool, a cross tip drive torque tool, and a flat tip drive torque tool.

17. 14. The core bolt of claim 13, wherein the stem portion (124, 424) is opposite a rotation feature (122, 422) of the torque portion (120, 420).

18. 14. The core bolt of claim 13, wherein the stem portion (124, 424) comprises at least one of an elongated cylindrical shape, an elongated hexagonal shape, and an elongated shape having multiple facets.

19. 14. The core bolt of claim 13, wherein the interface portion defines a break-neck groove disposed proximate the head portion at a central base area of ​​the recessed torque feature to facilitate separation of the frangible drive element from the core bolt in response to a predetermined torque being applied to the torque portion during installation of the core bolt.

20. The interface unit (118, 418) 14. The core bolt of claim 13, further comprising an interface body (204) that tapers from the stem portion (124, 424) to the head portion (106) at a central base area (116) of the recessed torque feature (202) to facilitate separation of the frangible drive element (112, 412) from the core bolt (100, 400) in response to a predetermined torque being applied to the torque portion (120, 420) during installation of the core bolt (100, 400).

21. 21. The core bolt of claim 20, wherein the interface body defines a break-neck groove disposed proximate the head portion in a central base area of ​​the recessed torque feature to further facilitate separation of the frangible drive element from the core bolt in response to the predetermined torque being applied to the torque portion during installation of the core bolt.

22. A fastener system (600, 800) for joining multiple substrates (602) of a workpiece (604) having a working surface (606) and a back surface (608), comprising: a nut member (610) including a nut bore (612) having an internal thread (614); The core bolt (100, 400) is provided, and the core bolt (100, 400) a head portion (106) with recessed torque features (202); a shank portion (108) extending axially from the head portion (106) along a central longitudinal axis (110) to a distal end (104) of the core bolt (100, 400), the shank portion (108) including a threaded portion (102) between the distal end (104) and the head portion (106); a frangible drive element (112, 412) extending from the head portion (106) and projecting outwardly along the central longitudinal axis (110) to define a proximal end (114) of the core bolt (100, 400).

23. The fastener system of claim 22, wherein said plurality of substrates (602) includes at least one composite substrate.

24. 23. The fastener system of claim 22, wherein a mating bore (702) extending through the plurality of substrates (602) at the working surface (606) of the workpiece (604) includes at least one of a countersink portion (704), a counterbore portion (706), and a cylindrical portion (708).

25. 23. The fastener system of claim 22, wherein the nut member is configured to position the nut bore over a mating bore that penetrates the plurality of substrates on the back surface of the workpiece.

26. The fastener system of claim 22, wherein the nut member (610) is configured to be secured to the back surface (608) of the workpiece (604).

27. 27. The fastener system of claim 26, wherein the nut member (610) is configured to be secured using at least one of a mechanical fastener, a nut plate, a swage retention mechanism, an adhesive to bond materials, and a gang channel.

28. 23. The fastener system of claim 22, wherein the core bolt is configured to be inserted into a mating bore extending through the plurality of substrates from the work surface of the workpiece.

29. 23. The fastener system of claim 22, wherein the threaded portion (102) of the shank portion (108) of the core bolt (100, 400) is configured to threadably engage the internal threads (614) of the nut member (610).

30. 23. The fastener system of claim 22, wherein the head portion (106) of the core bolt (100, 400) comprises at least one of a flush head, a countersunk head, a protruding head, and a raised head.

31. 23. The fastener system of claim 22, wherein the recessed torque feature (202) of the head portion (106) of the core bolt (100, 400) comprises at least one of a recessed offset cross drive feature, a recessed dovetail drive feature, a recessed cross tip drive feature, a recessed hex key drive feature, and a recessed flat tip drive feature.

32. 23. The fastener system of claim 22, wherein after the frangible drive element (112, 412) of the core bolt (100, 400) separates from the head portion (106), the recessed torque feature (202) of the head portion (106) facilitates rotation of the core bolt (100, 400) using at least one of an offset cruciform drive torque tool, a dovetail drive torque tool, a cross tip drive torque tool, a hex key drive torque tool, and a flat tip drive torque tool.

33. 23. The fastener system of claim 22, wherein the shank portion (108) of the core bolt (100, 400) is opposite the recessed torque feature (202) of the head portion (106).

34. 23. The fastener system of claim 22, wherein the shank portion (108) of the core bolt (100, 400) comprises at least one of a cylindrical body (302) and a frusto-conical body (304).

35. 23. The fastener system of claim 22, wherein the frangible drive element (112, 412) of the core bolt (100, 400) extends from the head portion (106) at a central base area (116) of the recessed torque feature (202) and is configured to be engaged by a tool for installation of the core bolt (100, 400).

36. 36. The fastener system of claim 35, wherein the tool comprises at least one of an end effector on a robotic arm, a gripping power tool, and a hand tool.

37. 36. The fastener system of claim 35, wherein the frangible drive element (112, 412) is separable from the head portion (106) at the central base area (116) of the recessed torque feature (202) in response to a predetermined torque being applied by the tool during installation of the core bolt (100, 400).

38. The frangible drive element (112, 412) of the core bolt (100, 400) is an interface portion (118, 418) extending from said head portion (106) and projecting outward; a torque portion (120, 420) including a rotation feature (122, 422) at the proximal end (114) of the core bolt (100, 400); and 23. The fastener system of claim 22, comprising a stem portion (124, 424) extending axially along the central longitudinal axis (110) of the core bolt (100, 400) between the interface portion (118, 418) and the torque portion (120, 420).

39. 39. The fastener system of claim 38, wherein the interface portion (118, 418) of the frangible drive element (112, 412) extends from the head portion (106) at a central base area (116) of the recessed torque feature (202).

40. 39. The fastener system of claim 38, wherein the rotation features (122, 422) of the torque portion (120, 420) include at least one of a recessed spline drive feature, a recessed star drive feature, a recessed square lobe star drive feature, a recessed six point star drive feature, a recessed six point square lobe star drive feature, an opposed flats head feature, a recessed hex key drive feature, a hex head feature, a recessed cross tip drive feature, and a recessed flat tip drive feature.

41. 39. The fastener system of claim 38, wherein the rotation feature (122, 422) of the torque portion (120, 420) facilitates rotation of the core bolt (100, 400) using at least one of a spline drive torque tool, a star drive torque tool, a square lobe star drive torque tool, a six point star drive torque tool, a six point square lobe star drive torque tool, an opposed flats socket torque tool, a hex key torque tool, a hex socket torque tool, a cross tip drive torque tool, and a flat tip drive torque tool.

42. 39. The fastener system of claim 38, wherein the stem portion (124, 424) of the frangible drive element (112, 412) is opposite the rotation feature (122, 422) of the torque portion (120, 420).

43. 40. The fastener system of claim 38, wherein the stem portion (124, 424) of the frangible drive element (112, 412) comprises at least one of an elongated cylindrical shape, an elongated hexagonal shape, and an elongated shape having multiple facets.

44. 39. The fastener system of claim 38, wherein the interface portion (118, 418) of the frangible drive element (112, 412) defines a break-neck groove (126) located proximate to the head portion (106) at a central base area (116) of the recessed torque feature (202) to facilitate separation of the frangible drive element (112, 412) from the core bolt (100, 400) in response to a predetermined torque being applied to the torque portion (120, 420) during installation of the core bolt (100, 400).

45. The interface portion (118, 418) of the frangible drive element (112, 412) is 39. The fastener system of claim 38, comprising an interface body (204) that tapers from the stem portion (124, 424) to the head portion (106) at a central base area (116) of the recessed torque feature (202) to facilitate separation of the frangible drive element (112, 412) from the core bolt (100, 400) in response to a predetermined torque being applied to the torque portion (120, 420) during installation of the core bolt (100, 400).

46. 46. ​​The fastener system of claim 45, wherein the interface body defines a break-neck groove located proximate the head portion in a central base area of ​​the recessed torque feature to further facilitate separation of the frangible drive element from the core bolt in response to the predetermined torque being applied to the torque portion during installation of the core bolt.

47. 23. The fastener system of claim 22, further comprising a sleeve member (802) including an outer sleeve surface (804) having a lubricating coating, the sleeve member (802) configured to be inserted into a joint bore (702) extending through the plurality of substrates (602) from the working surface (606) of the workpiece (604), and the core bolt (100, 400) configured to be inserted into the central bore (806) of the sleeve member (802).

48. 48. The fastener system of claim 47, wherein the lubricious coating on the outer sleeve surface (804) of the sleeve member (802) includes conductive features configured to provide electromagnetic energy protection to the workpiece (604).

49. 48. The fastener system of claim 47, wherein the outer sleeve surface (804) of the sleeve member (802) is coated with a conductive coating to provide electromagnetic energy protection to the workpiece (604).

50. 48. The fastener system of claim 47, wherein the sleeve member (802) further includes an inner sleeve surface (808), and the shank portion (108) of the core bolt (100, 400) includes an outer shank surface (810), and at least one of the inner sleeve surface (808) and the outer shank surface (810) is coated with the lubricating coating.

51. The sleeve member (802) an elongated sleeve body (812) defining the central bore (806), the elongated sleeve body (812) including the outer sleeve surface (804), an inner sleeve surface (808) facing the central bore (806), a first end (814) associated with the working surface (606) of the workpiece (604), and a second end (816) associated with the back surface (608) of the workpiece (604); 48. The fastener system of claim 47, wherein at least the inner sleeve surface (808) tapers from a larger inner sleeve diameter adjacent the first end (814) to a smaller inner sleeve diameter adjacent the second end (816) such that the central bore (806) comprises a frusto-conical sleeve bore (818).

52. 52. The fastener system of claim 51, wherein the outer sleeve surface (804) of the sleeve member (802) is cylindrically shaped such that the elongated sleeve body (812) includes a cylindrically shaped sleeve body (820) having the frustoconical sleeve bore (818).

53. 48. The fastener system of claim 47, wherein the shank portion (108) of the core bolt (100, 400) is configured to cause radial expansion of the sleeve member (802) when the core bolt (100, 400) is fully threaded onto the nut member (610), and the sleeve member (802) is configured to provide an interference fit within the mating bores (702) that extend through the plurality of base materials (602).

54. 23. The fastener system of claim 22, further comprising a thermoplastic polymer sealant (616) disposed in a cavity (822) between the nut member (610) and the back surface (608) of the workpiece (604).

55. 55. The fastener system of claim 54, wherein said thermoplastic polymer sealant (616) provides electromagnetic energy protection to said workpiece (604).

56. 23. The fastener system of claim 22, further comprising a cap sealant member (618) comprising a dome and configured to be disposed over the nut member (610) on the back surface (608) of the workpiece (604).

57. 57. The fastener system of claim 56, wherein said cap sealant member (618) provides electromagnetic energy protection to said workpiece (604).

58. A method (900) for joining multiple substrates (602) of a workpiece (604) having a working surface (606) and a back surface (608), comprising: securing (902) a nut member (610) over mating bores (702) extending through the plurality of substrates (602) on the back surface (608) of the workpiece (604), the nut member (610) including a nut bore (612) having an internal thread (614); Inserting (904) the core bolt (100, 400) into the mating bore (702) from the working surface (606) of the workpiece (604) until a distal end (104) of the core bolt (100, 400) contacts the nut member (610), the core bolt (100, 400) having a head portion (106) with a recessed torque feature (202) and a shank portion (110) extending axially from the head portion (106) along a central longitudinal axis (110) to the distal end (104) of the core bolt (100, 400). inserting (904) the core bolt (100, 400), the core bolt (100, 400) comprising a shank portion (108) having a threaded portion (102) between the distal end (104) and the head portion (106), the core bolt (100, 400) further comprising a frangible drive element (112, 412) extending from the head portion (106), the frangible drive element (112, 412) projecting outwardly along the central longitudinal axis (110) to define a proximal end (114) of the core bolt (100, 400); rotating (906) the core bolt (100, 400) to threadably engage the threaded portion (102) with the internal threads (614) of the nut member (610); and and further rotating (908) the core bolt (100, 400) for further threaded engagement with the nut member (610) until the frangible drive element (112, 412) separates from the core bolt (100, 400) to achieve installation.

59. Securing (902) the nut member (610) 59. The method of claim 58, comprising securing (1002) the nut member (610) to the backside (608) of the workpiece (604) using at least one of a mechanical fastener, a nut plate, a swage retention mechanism, an adhesive to bond materials, and a gang channel.

60. 59. The method of claim 58, wherein after the frangible drive element (112, 412) separates from the head portion (106), the recessed torque feature (202) of the head portion (106) facilitates rotation of the core bolt (100, 400) for removal of the workpiece (604) from the working surface (606) and subsequent replacement.

61. 59. The method of claim 58, wherein the shank portion (108) of the core bolt (100, 400) comprises at least one of a cylindrical body (302) and a frusto-conical body (304).

62. 59. The method of claim 58, wherein the frangible drive element (112, 412) of the core bolt (100, 400) extends from the head portion (106) at a central base area (116) of the recessed torque feature (202) and is configured to be engaged by a tool to at least one of rotate (906) the core bolt (100, 400) and further rotate (908) the core bolt (100, 400).

63. 63. The method of claim 62, wherein the tool comprises at least one of an end effector on a robotic arm, a gripping power tool, and a hand tool.

64. 63. The method of claim 62, wherein during further rotating (908) the core bolt (100, 400), the frangible drive element (112, 412) separates from the head portion (106) at the central base area (116) of the recessed torque feature (202) in response to a predetermined torque being applied by the tool.

65. The frangible drive element (112, 412) of the core bolt (100, 400) is an interface portion (118, 418) extending from said head portion (106) and projecting outward; a torque portion (120, 420) including a rotation feature (122, 422) at the proximal end (114) of the core bolt (100, 400); and 59. The method of claim 58, further comprising a stem portion extending axially along the central longitudinal axis of the core bolt between the interface portion and the torque portion, the stem portion being opposite the rotation feature of the torque portion.

66. 66. The method of claim 65, wherein the interface portion (118, 418) of the frangible drive element (112, 412) extends from the head portion (106) at a central base area (116) of the recessed torque feature (202).

67. Rotating (906) the core bolt (100, 400) and further rotating (908) the core bolt (100, 400) using a tool to engage (1102) the rotation feature (122, 422) of the torque portion (120, 420) of the frangible drive element (112, 412); using (1104) the tool to rotate the core bolt (100, 400) to threadably engage the threaded portion (102) of the shank portion (108) with the internal threads (614) of the nut member (610); and 66. The method of claim 65, comprising using (1106) the tool to further rotate the core bolt (100, 400) for further threaded engagement with the nut member (610) until the interface portion (118, 418) breaks and the frangible drive element (112, 412) separates from the core bolt (100, 400) to achieve the installation.

68. The interface portion (118, 418) of the frangible drive element (112, 412) defines a break-neck groove (126) disposed proximate to the head portion (106) at a central base area (116) of the recessed torque feature (202), and rotating (906) the core bolt (100, 400) and further rotating (908) the core bolt (100, 400) comprise: using a tool to engage (1202) the rotation feature (122, 422) of the torque portion (120, 420) of the frangible drive element (112, 412); using (1204) the tool to rotate the core bolt (100, 400) to threadably engage the threaded portion (102) of the shank portion (108) with the internal threads (614) of the nut member (610); and 66. The method of claim 65, comprising using (1206) the tool to further rotate the core bolt (100, 400) for further threaded engagement with the nut member (610) until the interface portion (118, 418) breaks at the break-neck groove (126) and the frangible drive element (112, 412) separates from the core bolt (100, 400) to achieve the installation.

69. the interface portion (118, 418) of the frangible drive element (112, 412) comprises an interface body (204) that tapers from the stem portion (124, 424) to the head portion (106) at a central base area (116) of the recessed torque feature (202), and rotating (906) the core bolt (100, 400) and further rotating (908) the core bolt (100, 400) using a tool to engage (1302) the rotation feature (122, 422) of the torque portion (120, 420) of the frangible drive element (112, 412); using (1304) the tool to rotate the core bolt (100, 400) to threadably engage the threaded portion (102) of the shank portion (108) with the internal threads (614) of the nut member (610); and 66. The method of claim 65, comprising using (1306) the tool to further rotate the core bolt (100, 400) for further threaded engagement with the nut member (610) until, to achieve the installation, the interface body (204) breaks at the central base area (116) of the recessed torque feature (202) of the head portion (106) of the core bolt (100, 400) and the frangible drive element (112, 412) separates from the core bolt (100, 400).

70. inserting (1402) a sleeve member (802) into the mating bore (702) extending through the plurality of substrates (602) from the working surface (606) of the workpiece (604), the sleeve member (802) including an outer sleeve surface (804) having a lubricious coating; and 60. The method (1400) of claim 58, further comprising inserting (1404) the core bolt (100, 400) into the central bore (806) of the sleeve member (802).

71. When the core bolt (100, 400) is fully threadedly engaged with the nut member (610), the method further comprises: radially expanding (1406) the sleeve member (802) within the mating bore (702) extending through the plurality of substrates (602) when the core bolt (100, 400) is fully threadedly engaged with the nut member (610); and 71. The method of claim 70, comprising providing (1408) an interference fit with the sleeve member (802) within the mating bore (702) in response to radial expansion of the sleeve member (802) when the core bolt (100, 400) is fully threaded with the nut member (610).

72. 59. The method (1500) of claim 58, further comprising, in conjunction with fixing (902) the nut member (610), applying (1502) a thermoplastic polymer sealant (616) to the nut member (610) such that the thermoplastic polymer sealant at least partially fills a cavity (822) between the nut member (610) and the back surface (608) of the workpiece (604).

73. 60. The method of claim 58, further comprising placing (1504) a cap sealant member (618) over the nut member (610) on the back surface (608) of the workpiece (604).

Images